Motivational Interviewing to Treat Overweight …...PEDIATRICS Volume 137 , number 1 , January 2016...
Transcript of Motivational Interviewing to Treat Overweight …...PEDIATRICS Volume 137 , number 1 , January 2016...
ARTICLEPEDIATRICS Volume 137 , number 1 , January 2016 :e 20151979
Motivational Interviewing to Treat Overweight Children: 24-Month Follow-Up of a Randomized Controlled TrialSerena Broccoli, PhD,a,b Anna Maria Davoli, MD,c Laura Bonvicini, MSc,a,b Alessandra Fabbri, MD,d Elena Ferrari, MD,c Gino Montagna, MD,c Costantino Panza, MD,c Mirco Pinotti, MD,e Simone Storani, PhD,f Marco Tamelli, PhD,f Silvia Candela, MD,a Eletta Bellocchio, MD,e Paolo Giorgi Rossi, PhDa,b
abstractBACKGROUND: Pediatrician-led motivational interviewing can be an effective way of controlling
BMI in overweight children in the short term. Its long-term efficacy is unknown. The
primary aim was to determine whether the short-term (12-month) impact of family
pediatrician-led motivational interviews on the BMI of overweight children could be
sustained in the long term (24 months), in the absence of any other intervention.
METHODS: Children were recruited in 2011 by family pediatricians working in the province of
Reggio Emilia, Italy, and randomly allocated to receive either 5 interviews delivered over
a 12-month period or usual care. Eligible participants were all 4- to 7-year-old overweight
children resident in the province of Reggio Emilia who had been receiving care from the
pediatrician for ≥12 months. The primary outcome of this study was individual variation in
BMI between the baseline visit and the 24-month follow-up, assessed by pediatricians not
blinded to treatment group allocation.
RESULTS: Of 419 eligible families, 372 (89%) participated; 187 children were randomized to
receive intervention and 185 to usual care. Ninety-five percent of the children attended
the 12-month follow-up, and 91% attended the 24-month follow-up. After the 12-month
intervention period, BMI in the intervention group increased less than in the control group
(0.46 and 0.78, respectively; difference −0.32; P = .005). At the 24-month follow-up, the
difference had disappeared (1.52 and 1.56, respectively; difference −0.04; P = .986).
CONCLUSIONS: The intervention lost its effectiveness within 1 year of cessation. Sustainable
boosters are required for weight control and obesity prevention.
aEpidemiology Unit, Azienda Unità Sanitaria Locale, Reggio Emilia, Italy; bArcispedale Santa Maria Nuova, Istituto
di Ricovero e Cura a Carattere Scientifi co - IRCCS, Reggio Emilia, Italy; cPrimary Care Pediatrician, dPublic
Health Nutrition Unit, and ePrimary Health Care, Local Health Authority, Reggio Emilia, Italy; fPromotion Health
Researchers, League Against Cancer, Reggio Emilia, Italy
Drs Broccoli, Fabbri, Ferrari, Montagna, Panza, and Candela and Ms Bonvicini contributed to study
design; Dr Broccoli and Ms Bonvicini coordinated data collection and carried out the analyses;
Drs Broccoli and Fabbri and Ms Bonvicini supervised data collection; Dr Broccoli drafted the
Methods, Results, and Discussion of the manuscript; Dr Davoli designed the study and coordinated
and supervised the pediatricians; Ms Bonvicini drafted the Introduction of the manuscript;
Drs Davoli, Fabbri, and Candela and Ms Bonvicini reviewed and revised the manuscript; Dr Fabbri
analyzed the results; Drs Ferrari and Montagna coordinated and supervised the recruitment
phase; Dr Ferrari assisted with training pediatricians and carrying out the study; Dr Montagna
assisted with carrying out the study; Drs Montagna (pediatrician component), Pinotti (Local
Health Unit component), and Bellocchio (Local Health Unit component) directed the pediatricians’
involvement; Drs Panza, Pinotti, and Bellocchio contributed to study development; Dr Panza
conducted the preliminary systematic review of the interventions; Drs Storani and Tamelli
contributed to intervention design and trained the pediatricians; Dr Candela developed the study;
Dr Rossi planned the data analysis, drafted the outline of the manuscript, and critically reviewed
and revised the manuscript; and all authors approved the fi nal manuscript as submitted.
To cite: Broccoli S, Davoli AM, Bonvicini L, et al. Motivational
Interviewing to Treat Overweight Children: 24-Month
Follow-Up of a Randomized Controlled Trial. Pediatrics.
2016;137(1):e20151979
WHAT’S KNOWN ON THIS SUBJECT: Childhood
obesity can seriously affect health outcomes.
Motivational interviewing in primary care has been
shown to be effective in BMI control, but previous
studies measured its effi cacy only just after the
intervention ended. There are no available long-term
follow-up data.
WHAT THIS STUDY ADDS: Despite very encouraging
initial results, 12 months after intervention ended,
children who received motivational interviewing lost
all the advantage in terms of BMI, compared with the
control group.
by guest on October 20, 2020www.aappublications.org/newsDownloaded from
BROCCOLI et al
The number of overweight or obese
children (0–5 years old) increased
from 31 million globally in 1990
to 44 million in 2012.1 Childhood
obesity is associated with a higher
chance of obesity, premature death,
and disability in adulthood. More
than 60% of children who are
overweight before puberty will
be overweight in early adulthood,
reducing the average age at which
noncommunicable diseases become
apparent and greatly increasing the
burden on health services, which
have to provide treatment during
much of their adult lives.2 At present,
there is lack of consensus worldwide
on which approaches and which
combinations of interventions
are likely to be most effective at
preventing childhood obesity in
different contexts and societies.3
Motivational interviewing (MIs)
has been applied to pediatric
populations over the last 2 decades4,5
and is recommended6 and widely
used7 for weight control and
obesity prevention. Nevertheless,
published studies8–13 evaluating
the influence of MI or behavioral
counseling on the BMI of overweight
children showed inconsistent
results. Although individual studies
reported mixed success, a recent
meta-analysis demonstrated that
behavioral strategies to improve
diet and physical activity (PA) were
efficacious in reducing children’s
BMI.14 In 2011, we conducted a
randomized trial in the province
of Reggio Emilia, Italy, to evaluate
the efficacy of pediatrician-led MI
in controlling BMI in overweight
children aged 4 to 7 years.15 Our
study concluded that MI was effective
at controlling the BMI of overweight
children (BMI percentile ≥85th and
<95th) in the short term. Despite
the encouraging short-term effect,
evidence of long-term efficacy is
required.16,17
In this article, we report the results of
the follow-up conducted 12 months
after the end of intervention.
METHODS
Study Design and Setting
The study is an individually
randomized controlled trial and
was conducted in the province of
Reggio Emilia, Italy, from 2011 to
2013. Reggio Emilia had a resident
population of 530 543 on January 1,
2011; 15.2% were children aged 0 to
14 years18 under the care of 82 public
health service family pediatricians.
In 2010, the estimated prevalence of
overweight children was 22%.19 The
methods used to conduct this trial
are published elsewhere15 and are
described briefly below.
Participants
Children were recruited through
their family pediatrician. A
maximum of 12 overweight children
(based on a previous survey) per
participating pediatrician were
randomly selected for eligibility
assessment. During a baseline visit
for eligibility assessment, the family
pediatrician proposed the study and
gave consent forms to parents of
eligible children. Eligible participants
were all overweight children (BMI
percentile ≥85th and <95th)20 aged
between 4 and 7 years, resident in
the province of Reggio Emilia, and
under the care of said pediatrician
for ≥12 months. Exclusion criteria
were metabolic pathologic conditions
and all pathologic conditions related
to obesity and being overweight.
Moreover, those families who did
not consider their children being
overweight to be an issue and
were not interested in the negative
consequences or advice on how
to lose weight (families in the
“precontemplation stage”) were also
excluded. Recruitment took place
from June to August 2011.
Randomization
The epidemiology unit used the
RALLOC package of Stata software to
randomly allocate eligible children
whose parents signed the informed
consent form to an intervention or
control group.21 The allocation rule
depended on the number of eligible
children. Pediatricians were not
blinded to the group allocation.
Intervention
The intervention consisted of 5 MIs
delivered at 1, 4, 7, and 12 months
after the baseline visit. Before
enrollment began, all pediatricians
attended a 4-hour training course on
how to accurately measure weight
and height and how to calculate the
BMI percentile, as well as a 20-hour
training course on MI conducted
by specialist psychologists from
“Luoghi di Prevenzione,” the regional
reference center for training in health
promotion.22 As previously reported,
94% of participants allocated to the
intervention group completed all 5
MIs.15 The intervention was based
on the transtheoretical model of
addiction and behavioral change.23
The child and parents always had
to leave the meeting having agreed
on 2 clearly defined and achievable
objectives (1 concerning food and
1 concerning PA improvements).
During each subsequent interview,
the extent to which the objectives
set at the previous meeting had
been achieved was assessed. The
objectives were then reinforced or
redefined and recorded accordingly.
Participants who were randomly
assigned to the control group
attended the baseline and 12-month
visits. They received a booklet with
the main information on obesity
prevention (eg, opportunistic
healthy diet recommendations if the
pediatrician was seeing the child for
other reasons). All children were
invited to attend a follow-up visit
24 months after the baseline, eg, 12
months after the intervention had
finished.
Data Collection and Outcomes
Baseline and follow-up data
were collected by means of a
corporate Intranet Web form
customized for the trial, compiled
2 by guest on October 20, 2020www.aappublications.org/newsDownloaded from
PEDIATRICS Volume 137 , number 1 , January 2016
by the pediatrician. Dietary and
PA habits were assessed using the
questionnaire from the Italian survey
on childhood obesity “OKKIO alla
Salute,”24 conducted periodically
by Italy’s National Institute of
Health and part of the World Health
Organization European region
Childhood Obesity Surveillance
Initiative25; some items were
supplemented with regional food
names. Sociodemographic data on
the parents and child was collected
at the baseline visit. Weight, height,
BMI, BMI percentile, and dietary and
PA habits were assessed at baseline
and at 12- and 24-month follow-up
visits. The primary outcome of the
study was the individual BMI score
variation (Δ0–24BMI) between the
baseline and 24-month follow-up
visits (long-term effect).26 The
secondary outcomes were the
percentage of positive changes in
parent-reported dietary behavior
and PA between the baseline and
24-month follow-up visits.
Sample Size
The study was sized to detect a
between-group difference in ΔBMI
of ≥0.5 with a 5% significance level
and a power of 90%, assuming an SD
of ΔBMI of 1. The smallest possible
sample size was 85 children per
group. Considering a 30% dropout
rate, recruitment of at least 110
children per arm was planned.
Statistical Analysis
Data analysis was performed using
Stata statistical software, version
13.0. Primary objective analysis
was conducted on the basis of an
intention-to-treat approach, replacing
missing Δ0–24BMI values with the
mean BMI variation observed in
the control group. All inferential
analyses were performed using
weights to balance allocation within
strata.15 Mean Δ0–24BMI, Δ0–24BMI
z-score, and relative 95% confidence
interval (CI) were presented by
study group. Δ0–24BMI, Δ0–12BMI
(short-term effect), and Δ12–24BMI
(rebound effect) in the intervention
and control groups were compared
using nonparametric Wilcoxon–
Mann–Whitney test because
the outcome was not normally
distributed. Multilevel linear models
were developed to measure the
influence of pediatricians on long-
term effectiveness. Two multilevel
models were specified: random
intercept and random intercept
and slopes. The intrapediatrician
correlation coefficient was reported
with the likelihood ratio test to
compare models. Post hoc subgroup
analyses were performed by gender,
age at baseline (<6 or ≥6 years),
and mother’s level of education
(<13, 13, or >13 years of schooling).
Changes in PA and dietary habits in
intervention and control groups were
compared using Wilcoxon rank sum
test.
We performed a formal mediation
analysis to distinguish the direct
effect of the intervention on BMI
and its mediated effect through diet
and physical activity. The analysis
comprised 3 steps: (1) checking the
association between the intervention
and the putative mediator; (2)
checking the association between
the putative mediator and BMI;
and (3) calculating the mediation
percentage, eg, the proportion of the
intervention effect on BMI mediated
by the mediator. Twelve-month
variations were considered, eg, 0–12
and 12–24, and the intervention was
categorized in 3 ways: untreated,
treatment period, and posttreatment.
This analysis included all the dietary
and PA variables associated with the
BMI z-score (P < .05). Separate age-
adjusted models were developed for
each putative mediator.
RESULTS
Four hundred nineteen parents were
asked to consent to their child’s
participation in the study, and 372
signed the informed consent form;
187 were randomized to intervention
and 185 to usual care. The
intervention and usual care groups
had similar baseline characteristics
(gender, breastfeeding, overweight
before the age of 5 years, gestational
age at birth, small for gestational
age, parent level of education, parent
weight, baseline age, and baseline
BMI).15
Participation in 12-Month Follow-Up
Of the 187 participants in the
intervention group, 167 (89.3%)
attended the 24-month follow-up
visit, as did 170 (91.9%) of the 185
participants in the usual care group.
One treated child was excluded
from the analysis because, during a
follow-up assessment, a pediatrician
noted that the weight and height
measurements had been recorded
incorrectly at the baseline visit
and, on the basis of the up-to-date
information, the child was not eligible
to take part27 (Fig 1). There were no
differences in baseline characteristics
between participants who provided
data at the 12-month follow-up and
those who did not. At 24 months,
a greater proportion of children
with Italian-born parents attended
the follow-up visit compared with
children with ≥1 immigrant parent
(94% vs 62%; P < .001).
Effect on BMI
At the 24-month follow-up, there
were no significant differences
between groups in terms of the
Δ0–24BMI score: −0.04 (95%
CI −0.36 to 0.28). During the
postintervention period (between
the 12- and 24-month follow-ups),
mean BMI increased more among
children in the intervention group
(Δ12–24BMI 1.06% [95% CI 0.90 to
1.22]) than in the usual care group
(Δ12–24BMI 0.78% [95% CI 0.59 to
0.97]) (rebound effect). (Table 1)
The proportion of pediatrician-level
variance on the overall variation
in Δ0–24BMI (intraclass correlation
coefficient) was 7.2%. Mean Δ0–24BMI
3 by guest on October 20, 2020www.aappublications.org/newsDownloaded from
BROCCOLI et al
in the control group differed
significantly across pediatricians
(likelihood ratio test, random-
intercept versus linear-regression
model: χ2[2] = 7.72, P = .0211). The
lack of long-term effectiveness of
MI did not vary significantly across
pediatricians (likelihood ratio test,
random-intercept and slope versus
random-intercept model: χ2[2] =
0.30, P = .8602). The results were
similar if only the rebound effect was
taken into consideration.
Subgroup Analysis
The long-term effect was similar by
gender (interaction test P = .332),
although breaking down the results
into short-term and rebound effects
showed that the short-term effect
was stronger in girls (Δ0–12BMI
−0.54 and 0.0 for females and males,
respectively, interaction test P = .053),
as was the rebound effect (Δ12–24BMI
0.36 and 0.16 for females and males,
interaction test P = .421) (Table 2; Fig
2). There was no interaction between
age and intervention (interaction
test P = .333) (Table 2). MI had a
positive long-term effect on Δ0–24BMI
in children whose mother had a high
(Δ0–24BMI −0.73% [95%CI −1.65 to
0.18]) or medium (Δ0–24BMI −0.31%
[95% CI −0.74 to 0.13]) level of
education, whereas it had a negative
long-term effect in children whose
mother had a low level of education
(Δ0–24BMI 0.66% [95% CI 0.08 to
1.23) (interaction test P = .008). The
same results were observed in the
short term (Table 2; Fig 3).
Effect of Diet and PA on BMI Changes
Several improvements in behaviors
were evident in the MI group in
the short term,15 but almost no
improvements were observed during
the follow-up period. As a result, the
long-term effect showed only modest
improvements in nonorganized PA
(P = .072), fruit intake (P = .070), and
the consumption of sweet snacks/
candies (P = .066), desserts (P =
.047), and sweetened drinks (P =
.004) (Table 3). The only 2 exceptions
were having breakfast and eating
fruit, for which improvements were
observed during both periods (Table
3), but they were not associated
with BMI. Only parent-reported
nonorganized PA and vegetable and
dessert consumption were associated
with BMI variations (Table 4). The
mediation analysis showed that the
increase in nonorganized PA and the
decrease in dessert consumption
accounted for 7.7% (95% CI 4.5 to
22.7) and 8.6% (95% CI 5.0 to 27.7),
respectively, of the total effect of the
intervention on the BMI z-score.
DISCUSSION
In 2013, we published the positive
results of MI intervention conducted
by pediatricians in an Italian
province.15 We concluded that
intervention was effective in the
short term, although the results
were less convincing for boys
and for children whose mothers
had low levels of education. Our
positive conclusions have now been
dampened by the follow-up results
for the children enrolled in the trial,
as reported in this article: 12 months
after the end of the intervention,
the advantages observed in the
intervention group had almost
disappeared and, in fact, the rebound
effect in the intervention group
produced a greater increase in BMI
than in the control group.
Gender and mother’s level of
education were found to play an
4
FIGURE 1Flow chart of study participants. aDuring follow-up assessment, a pediatrician reported an error in the weight and height measurement at baseline. According to update information, the child was not eligible and we decided to exclude her from the “intention to treat” population.
by guest on October 20, 2020www.aappublications.org/newsDownloaded from
PEDIATRICS Volume 137 , number 1 , January 2016
important role in determining
the outcome. Whereas benefits
disappeared after the 12-month
follow-up visit for children whose
mothers had spent >13 years at
school, the effects of intervention
5
seem counterproductive in the long
term for children whose mothers
had received <13 years of education.
The child’s gender also modified the
effect of our proposed MI, but unlike
the low level of maternal education,
the lack of an effect in boys was
not followed by a rebound effect,
meaning that the intervention does
not help boys, but also that it does
not harm them.
Our results are consistent with
previous results in adults,28–30 where
the success of initial motivational
interviewing in BMI control and
changing diet and levels of PA is
often followed by a lack of long-
term efficacy. A relapse once MI has
been discontinued is considered
an intrinsic characteristic of these
interventions.31,32
Nevertheless, 2 more recent studies
reported the effect of MI over the
course of 24 months.12,13 In Resnicow
et al, the study population and the
intervention were quite similar to
those of our own study, although
only 4 interviews were distributed
throughout the entire 24-month
period and 1 of the intervention
groups included a dietitian
interview.12 The study observed a
larger δ in BMI variation between
the intervention group and the usual
care group than we observed during
TABLE 1 BMI Score, BMI Z-Score, BMI Percentile, Δ0–24BMI (Primary Outcome, Long-term Effect),
Δ0–12BMI (Short-term Effect), and Δ12–24BMI (Rebound Effect) by Study Group
Outcome Intervention Usual Care Between-Group
Difference in ΔBMI Score
and z-Score
Baseline
BMI score 18.27 (18.16 to 18.38) 18.21 (18.10 to 18.33)
BMI z-score 1.35 (1.32 to 1.38) 1.35 (1.32 to 1.37)
BMI percentile 90.96 (90.53 to 91.38) 90.88 (90.46 to 91.30)
12-mo follow-up
BMI score 18.73 (18.51 to 18.96) 18.99 (18.78 to 19.21)
BMI z-score 1.23 (1.17 to 1.30) 1.34 (1.28 to 1.40)
BMI percentile 87.39 (86.03 to 88.75) 89.33 (88.22 to 90.44)
24-mo follow-up
BMI score 19.79 (19.53 to 20.05) 19.77 (19.51 to 20.04)
BMI z-score 1.29 (1.22 to 1.37) 1.31 (1.25 to 1.38)
BMI percentile 87.99 (86.50 to 89.49) 88.41 (87.07 to 89.76)
Long-term effect
Δ0–24BMI score 1.52 (1.29 to 1.75) 1.56 (1.33 to 1.79) −0.04 (−0.36 to 0.28)*
Δ0–24BMI z-score −0.05 (−0.12 to 0.01) −0.03 (−0.09 to 0.02) −0.02 (−0.11 to 0.07)
Short-term effect
Δ0–12BMI score 0.46 (0.27 to 0.65) 0.78 (0.61 to 0.96) −0.32 (−0.57 to −0.06)**
Δ0–12BMI z-score −0.12 (−0.17 to −0.06) −0.01 (−0.06 to 0.04) −0.11 (−0.18 to −0.03)
Rebound effect
Δ12–24BMI score 1.06 (0.90 to 1.22) 0.78 (0.59 to 0.97) 0.28 (0.03 to 0.52)***
Δ12–24BMI z-score 0.06 (0.02 to 0.10) −0.03 (−0.08 to 0.02) 0.09 (0.02 to 0.15)
Data are expressed as mean (95% CI).
Wilcoxon–Mann–Whitney test: *P = .986, **P = .005; ***P = .011.
TABLE 2 Δ0–24BMI Score, Δ0–12BMI Score, and Δ12–24BMI Score by Gender, Children’s Age, Maternal Level of Education, and Study Group
Characteristic Long-Term Effect (Δ0–24BMI Score) Short-Term Effect (Δ0–12BMI Score) Rebound Effect (Δ12–24BMI Score)
Intervention Usual Care Pa Intervention Usual
Care
Pa Intervention Usual
Care
Pa
Gender .332 .053 .421
Male 1.69 (1.30 to
2.08)
1.53 (1.14 to
1.92)
0.77 (0.46 to 1.07) 0.77 (0.44
to 1.10)
0.92 (0.68 to 1.17) 0.76 (0.50
to 1.02)
Female 1.40 (1.12 to
1.68)
1.58 (1.28 to
1.87)
0.25 (0.02 to 0.48) 0.79 (0.56
to 0.99)
1.15 (0.94 to 1.37) 0.79 (0.54
to 1.04)
Age, y .333 .843 .291
<6 1.74 (1.34 to
2.15)
1.55 (1.15 to
1.94)
0.46 (0.13 to 0.78) 0.74 (0.42
to 1.06)
1.29 (0.95 to 1.62) 0.81 (0.52
to 109)
≥6 1.43 (1.15 to
1.70)
1.57 (1.28 to
1.86)
0.46 (0.23 to 0.69) 0.80 (0.59
to 1.01)
0.96 (0.78 to 1.14) 0.77 (0.52
to 1.01)
Mother’s level of
education, y of
school
.008 .004 .774
<13 2.04 (1.65 to
2.42)
1.38 (0.95 to
1.81)
0.86 (049 to 1.23) 0.61 (0.32
to 0.91)
1.18 (0.88 to 1.47) 0.77 (0.42
to 1.11)
13 1.35 (1.04 to
1.65)
1.65 (1.34 to
1.97)
0.34 (0.13 to 0.56) 0.86 (0.61
to 1.11)
1.00 (0.77 to 1.23) 0.79 (0.53
to 1.06)
>13 0.77 (0.13 to
1.40)
1.5 (0.81 to
2.20)
−0.2 (−0.71 to 0.30) 0.84 (0.31
to 1.36)
0.97 (0.58 to 1.36) 0.67 (0.24
to 1.10)
Data are expressed as mean (95% CI).a Interaction test.
by guest on October 20, 2020www.aappublications.org/newsDownloaded from
BROCCOLI et al
our 12-month intervention period.
This larger effect could be because
the study analyzed only children
who were not lost during follow-up,
the longer period of intervention,
the involvement of paid volunteer
pediatricians, or the inclusion of
dietitians in the intervention. On the
other hand, the authors only report
data at the end of intervention, which
is not comparable with our 24-month
follow-up data and, to date, it is not
known whether a rebound would
also occur after the 24-month period
covered by their study.
Taylor et al reported positive
long-term results of family-based
intervention addressing overweight
and obese children aged 4 to 8
years.13 This intervention is tailored
to the needs of each family and
consists of frequent, low-dose contact
over a 2-year period (total contact
time was 6 to 7 hours per family).
The Δ0–24BMI z-score difference
between the intervention and control
group was −0.12 (95% CI −0.20
to −0.04), which is consistent with
our findings after 12 months of
intervention. The long-term efficacy
after the intervention has not been
investigated.
It is encouraging that 3 trials12,13,15
conducted in very different contexts
and health systems showed
improvements after MI interventions
delivered in a primary care setting, at
least for as long as the intervention
was still in progress, in line with
results of a recent systematic
review.14
The family, particularly the mother,
also proved to be an important
effect modifier for the long-term
maintenance of the effects in other
studies.33,34 In our setting, some
pediatricians reported that the
motivational diagnosis was more
difficult and less accurate when
the mother had a lower level of
education. The potentially harmful
effect of MI when administered
in precontemplative subjects has
been postulated in theory and also
observed in experimental settings.35
The observed results stress the
need for an accurate motivational
diagnosis in all families.
In our population, the changes in BMI
in the intervention and control group
were consistent with the changes
in diet and physical activity at the
end of the intervention.15 During
the follow-up period, the changes
in parent-reported diet and PA no
longer showed any benefit in the
intervention group compared with
the control group. We conducted
an analysis trying to understand
which dietary and PA changes played
the biggest part in the mechanism
leading to BMI reduction after
intervention and BMI rebound
after intervention cessation. Only 2
behavioral factors were found to be
weak mediators of the intervention
effect on BMI: nonorganized PA and
dessert consumption.
Strengths and Limitations
The follow-up visit was well
attended, and there was good
compliance with treatment, with
positive feedback from families and
children. The study maintained a
good level of statistical power, at
least for the primary endpoint.
One of the main limitations of the
follow-up study was the risk of
6
FIGURE 2BMI z-score trajectories by gender and study group.
by guest on October 20, 2020www.aappublications.org/newsDownloaded from
PEDIATRICS Volume 137 , number 1 , January 2016
randomized group contamination
after the end of the intervention.
In fact, the study protocol
recommended offering usual care
only once the intervention was over,
to both treated children and those
from the control group. However,
it cannot be ruled out that the
pediatricians may have adopted a
different approach to usual care
after training and experience with
MI techniques developed during the
trial. Moreover, we did not ask them
to record contact with participants
during the follow-up period.
Interestingly, we observed a rebound
effect during the follow-up period
rather than an improvement in the
control group, as would be expected
in the case of contamination. What
is more, the rebound effect did
not differ between pediatricians,
suggesting an effect independent
from the pediatrician’s approach.
Another limitation of the study is that
parent-reported dietary habits may
be strongly affected by desirability
bias, and the bias may be stronger for
those who received the intervention
with 4 MIs in which they had to agree
on dietary habit and PA targets than
for families in the control group. This
bias can lead to an overestimation
relating to the effect of intervention
on dietary and PA habits and could
also explain why at 24 months we
still observed an effect on some
lifestyle habits but not on BMI.
Nevertheless, desirability bias does
not have an excessive influence on
the results of the mediation analysis,
where we compare the relative
influence of different behavioral
variables in both groups during the
intervention and follow-up periods.
Considerations on Designing Effective Long-Term Intervention
According to the review by Janicke et
al14 and the experiences reported by
Resnicow et al12 and Taylor et al,13 it
seems that longer intervention with
fewer interviews per year or with
more shorter interviews tailored to
the needs of each family could at least
maintain the effectiveness of MI for
24 months, with similar consumption
of resources.
Some studies in the child obesity
literature have reported the
positive long-term effects of
different individual interventions:
long-term interventions, including
boosters, based on family-based
behavioral intervention in primary
care36; parent-centered dietary-
modification programs combined
with child-centered physical-activity
skill-development programs37;
or structured outpatient training
programs consisting of physical
exercise, nutritional education, and
behavioral therapy.38,39
Wilfley et al40 demonstrated that
maintenance treatments based
on behavioral skills and social
facilitation improve the long-term
efficacy of weight loss treatments.
Researchers have underlined
the need for strong maintenance
treatments to sustain effects after
weight loss treatment.34 We are
therefore planning MI reinforcement
for the treated children, while
continuing to monitor the control
group.
The intervention proposed in
this trial has been designed to be
sustainable and feasible when
scaled up to the entire population
of overweight 5-year-olds in the
7
FIGURE 3BMI z-score trajectories by maternal level of education and study group.
by guest on October 20, 2020www.aappublications.org/newsDownloaded from
BROCCOLI et al
province of Reggio Emilia.15 A longer
intervention risks disrupting the
sustainability of the intervention.
The cost-effectiveness and cost
opportunity of longer individual
interventions should be compared
with the costs of community-based
interventions.
Finally, it must be considered that
even interventions proven to be
effective in some groups can be
completely ineffective or damaging in
others, highlighting the importance of
considering pretreatment variables
(BMI at baseline, family support)
as modifiers of the effectiveness of
different strategies.34 This was the
case for our intervention, which had
no effect on boys or children whose
mothers had low levels of education.
CONCLUSIONS
The long-term effectiveness of MI in
BMI control cannot be inferred on
the basis of immediate effectiveness.
There is a need for sustainable and
effective boosters and maintenance
strategies for MI interventions.
ACKNOWLEDGMENTS
We are grateful to all pediatricians
working in the Province of Reggio
Emilia for their participation in this
project. Their work and attention to
details contributed to the success of
the study. We wish to thank Paola
Albertini (Local Health Authority,
Reggio Emilia) for her support
and assistance in providing the
customized corporate Intranet Web
form for the trial.
ABBREVIATIONS
CI: confidence interval
MI: motivational interviewing
PA: physical activity
8
TABL
E 3
Per
cen
t of
Ch
ange
s (P
osit
ive
or N
egat
ive)
in P
aren
t-R
epor
ted
PA
and
Die
tary
Hab
its
by
Stu
dy
Gro
up
an
d P
erio
d
Hab
it
0- t
o 12
-mo
Ch
ange
s, %
12- t
o 24
-mo
Ch
ange
s, %
0- t
o 24
-mo
Ch
ange
s, %
Inte
rven
tion
Usu
al C
are
Pa
Inte
rven
tion
Usu
al C
are
Pa
Inte
rven
tion
Usu
al C
are
Pa
nN
egP
osn
Neg
Pos
nN
egP
osn
Neg
Pos
nN
egP
osn
Neg
Pos
PA
hab
its
O
rgan
ized
PAb
174
8.6
22.4
175
8.6
22.3
.964
167
16.8
20.4
161
17.4
19.3
.860
168
7.7
24.4
157
11.5
24.2
.655
N
onor
gan
ized
PAb
174
12.6
35.1
175
24.0
25.1
.007
167
34.7
15.6
160
36.3
18.1
.725
168
26.2
29.8
156
35.3
23.1
.072
S
cree
n t
imec
174
8.0
19.5
174
11.5
13.2
.056
168
14.9
8.9
161
13.0
9.3
.640
169
16.0
23.7
156
16.0
13.5
.103
Die
tary
hab
its
H
avin
g b
reak
fast
b17
38.
116
.817
28.
111
.0.2
3316
26.
89.
915
69.
09.
0.4
9816
43.
017
.715
69.
610
.9.0
09
Ve
geta
ble
sb17
418
.437
.917
417
.224
.1.0
7316
835
.125
.016
126
.724
.8.3
9916
928
.435
.515
726
.129
.3.6
43
Ve
geta
l sou
pb
174
7.5
17.8
175
12.6
10.9
.023
168
17.9
13.7
161
11.8
14.3
.237
169
10.1
17.2
157
12.7
16.6
.589
Fr
uit
b17
417
.235
.117
518
.930
.3.4
3216
834
.523
.816
137
.319
.3.5
4916
923
.129
.615
731
.219
.7.0
70
S
wee
t sn
acks
/
can
die
sc17
310
.453
.817
520
.633
.7<
.001
167
30.5
22.2
160
22.5
32.5
.033
169
11.2
49.7
156
21.2
44.9
.066
D
esse
rtsc
174
12.6
36.2
175
19.4
26.3
.012
168
22.0
19.6
161
21.7
23.6
.639
169
14.8
37.3
157
20.4
28.7
.047
S
alty
sn
acks
c17
410
.326
.417
514
.920
.0.0
8116
719
.213
.816
116
.118
.0.2
2416
814
.926
.215
715
.926
.8.9
17
Fr
ied
foo
dc
174
9.8
23.0
175
12.0
14.3
.050
168
15.5
11.9
161
14.9
11.2
.992
169
10.7
18.9
157
12.7
12.1
.110
S
wee
ten
ed d
rin
ksc
174
8.0
46.0
175
17.1
32.0
<.0
0116
822
.622
.016
021
.922
.5.9
3716
911
.250
.315
617
.938
.5.0
04
Neg
, neg
ativ
e; P
os, p
osit
ive.
a P
rob
abili
ty t
hat
th
e d
irec
tion
of
chan
ges
is n
ot d
iffe
ren
t in
2 g
rou
ps
by
Wilc
oxon
ran
k su
m t
est
com
par
ing
the
ran
k of
ch
ange
s ac
cord
ing
to t
he
cate
gori
es (
0, 1
–3,
4–
5, >
5, 1
/day
, mor
e) a
nsw
ered
in t
he
qu
esti
onn
aire
.b In
crea
ses
in t
ime
spen
t or
con
sum
pti
on a
re c
onsi
der
ed p
osit
ive
chan
ges.
c D
ecre
ases
in t
ime
spen
t or
con
sum
pti
on a
re c
onsi
der
ed p
osit
ive
chan
ges.
by guest on October 20, 2020www.aappublications.org/newsDownloaded from
PEDIATRICS Volume 137 , number 1 , January 2016
REFERENCES
1. World Health Organization (WHO).
World Health Statistics 2014. Geneva,
Switzerland: World Health Organization;
2014
2. Branca F, Nikogosian H, Lobstein T, eds.
The Challenge of Obesity in the WHO
European Region and the Strategies
for Response: Summary. Geneva,
Switzerland: World Health Organization;
2007
3. Sabin MA, Kao KT, Juonala M, Baur LA,
Wake M. Viewpoint article: Childhood
obesity: looking back over 50 years to
begin to look forward. J Paediatr Child
Health. 2015;51(1):82–86
4. Erickson SJ, Gerstle M, Feldstein SW.
Brief interventions and motivational
interviewing with children,
adolescents, and their parents in
pediatric health care settings: a
review. Arch Pediatr Adolesc Med.
2005;159(12):1173–1180
5. Suarez M, Mullins S. Motivational
interviewing and pediatric health
behavior interventions. J Dev Behav
Pediatr. 2008;29(5):417–428
6. Barlow SE; Expert Committee. Expert
committee recommendations
regarding the prevention, assessment,
and treatment of child and adolescent
overweight and obesity: summary
report. Pediatrics. 2007;120(4 Suppl
4):S164–S192
7. Christie D, Channon S. The potential
for motivational interviewing to
improve outcomes in the management
of diabetes and obesity in paediatric
and adult populations: a clinical
review. Diabetes Obes Metab.
2014;16(5):381–387
8. Taveras EM, Gortmaker SL, Hohman
KH, et al. Randomized controlled trial
to improve primary care to prevent
and manage childhood obesity: the
High Five for Kids study. Arch Pediatr
Adolesc Med. 2011;165(8):714–722
9. Bocca G, Corpeleijn E, Stolk RP, Sauer
PJ. Results of a multidisciplinary
treatment program in 3-year-old
to 5-year-old overweight or obese
children: a randomized controlled
clinical trial. Arch Pediatr Adolesc Med.
2012;166(12):1109–1115
10. Walpole B, Dettmer E, Morrongiello BA,
McCrindle BW, Hamilton J. Motivational
interviewing to enhance self-effi cacy
and promote weight loss in overweight
9
This trial has been registered at www. clinicaltrials. gov (identifi er NCT01822626).
DOI: 10.1542/peds.2015-1979
Accepted for publication Oct 15, 2015
Address correspondence to Serena Broccoli, Epidemiology Unit, Local Health Authority of Reggio Emilia, via Amendola 2, Reggio Emilia, Italy. E-mail: serena.
PEDIATRICS (ISSN Numbers: Print, 0031-4005; Online, 1098-4275).
Copyright © 2016 by the American Academy of Pediatrics
FINANCIAL DISCLOSURE: The authors have indicated they have no fi nancial relationships relevant to this article to disclose.
FUNDING: No external funding.
POTENTIAL CONFLICT OF INTEREST: The authors have indicated they have no potential confl icts of interest to disclose.
TABLE 4 Multivariate Linear Regression Models of ∆Habit on ∆BMI Z-Score, Total and Stratifi ed by Study Group and Period
Habit n Total Modela Stratifi ed Modelsb
Habits Variation P for
Interaction
Usual Care MI (0–12) MI (12–24)
βc P βc P βc P βc P
PA habits
Organized PAd 354 −0.003 .861 .875
Nonorganized PAd 354 −0.018 .050 .748
Screen timee 354 −0.042 .093 .586
Dietary habits
Having breakfastd 349 −0.001 .976 .164 −0.019 .428 0.006 .840 0.058 .078
Vegetablesd 354 −0.031 .001 .027 −0.003 .834 −0.053 .001 −0.052 <.001
Vegetal soupd 354 −0.022 .210 .936
Fruitd 354 −0.012 .159 .040 0.013 .409 −0.022 .235 −0.038 .004
Sweet snacks/candiese 353 0.014 .138 .726
Dessertse 354 0.027 .041 .144 0.030 .167 0.001 .970 0.056 .002
Salty snackse 354 0.034 .105 .204
Fried foode 354 0.020 .432 .370
Sweetened drinkse 354 0.003 .818 .215
a Linear regression models: ∆BMI z-score = ∆Habit + group + age + interaction(∆Habit × group).b Linear regression models by study group: ∆BMI z-score = ∆Habit + age; only reported if P for interaction <.2.c Negative coeffi cients correspond to a decrease in BMI and positive coeffi cients correspond to an increase in BMI.d Increases in time spent or consumption are considered behavioral improvements.e Increases in time spent or consumption are considered behavioral worsening.
by guest on October 20, 2020www.aappublications.org/newsDownloaded from
BROCCOLI et al
and obese adolescents: a randomized
controlled trial. J Pediatr Psychol.
2013;38(9):944–953
11. van Grieken A, Veldhuis L, Renders
CM, et al. Population-based childhood
overweight prevention: outcomes of
the ‘Be active, eat right’ study. PLoS
One. 2013;8(5):e65376
12. Resnicow K, McMaster F, Bocian A,
et al. Motivational interviewing and
dietary counseling for obesity in
primary care: an RCT. Pediatrics. 2015;
135(4). Available at: www. pediatrics.
org/ cgi/ content/ full/ 135/ 4/ e649
13. Taylor RW, Cox A, Knight L, et al.
A tailored family-based obesity
intervention: a randomized trial.
Pediatrics. 2015;136(2). Available at:
www. pediatrics. org/ cgi/ content/ full/
136/ 2/ e281
14. Janicke DM, Steele RG, Gayes LA, et al.
Systematic review and meta-analysis
of comprehensive behavioral family
lifestyle interventions addressing
pediatric obesity. J Pediatr Psychol.
2014;39(8):809–825
15. Davoli AM, Broccoli S, Bonvicini L,
et al. Pediatrician-led motivational
interviewing to treat overweight
children: an RCT. Pediatrics. 2013;
132(5). Available at: www. pediatrics.
org/ cgi/ content/ full/ 132/ 5/ e1236
16. Jones RA, Sinn N, Campbell KJ, et al.
The importance of long-term follow-up
in child and adolescent obesity
prevention interventions. Int J Pediatr
Obes. 2011;6(3–4):178–181
17. Altman M, Wilfl ey DE. Evidence update
on the treatment of overweight and
obesity in children and adolescents.
J Clin Child Adolesc Psychol.
2015;44(4):521–537
18. Istat. Demography in Figures [in
Italian]. Available at: http:// demo. istat.
it/ . Accessed June 1, 2013
19. Fabbri A, Palomba A. OKkio alla
SALUTE. Risultati Dell’indagine 2010.
AUSL di Reggio Emilia. Available at:
www. epicentro. iss. it/ okkioallasalute/
reportregionali20 10/ Emilia- Romagna_
Okkio2010. pdf. Accessed September 13,
2013
20. Kuczmarski RJ, Ogden CL, Guo SS, et al.
2000 CDC growth charts for the United
States: methods and development.
Vital Health Stat 11. 2002;(246):1–190
21. StataCorp. Stata Statistical Software:
Release 13 [computer software].
College Station, TX: StataCorp; 2009
22. Luoghi di Prevenzione. Regional
multimedia teaching centre on
promotion of health. Available at: www.
luoghidiprevenzio ne. it. Accessed May
21, 2015
23. Prochaska JO, Velicer WF. The
transtheoretical model of health
behavior change. Am J Health Promot.
1997;12(1):38–48
24. OKkio alla SALUTE. In Primo Piano.
Available at: www. epicentro. iss. it/
okkioallasalute/ . Accessed August 28,
2015
25. Wijnhoven T, Branca F. WHO European
Childhood Obesity Surveillance
Initiative. Protocol, Version January
2008. Copenhagen, Denmark: WHO
Regional Offi ce for Europe; 2008
26. Cole TJ, Faith MS, Pietrobelli A, Heo M.
What is the best measure of adiposity
change in growing children: BMI, BMI
%, BMI z-score or BMI centile? Eur J
Clin Nutr. 2005;59(3):419–425
27. Fergusson D, Aaron SD, Guyatt
G, Hébert P. Post-randomisation
exclusions: the intention to treat
principle and excluding patients from
analysis. BMJ. 2002;325(7365):652–654
28. West DS, DiLillo V, Bursac Z, Gore SA,
Greene PG. Motivational interviewing
improves weight loss in women
with type 2 diabetes. Diabetes Care.
2007;30(5):1081–1087
29. Elliot DL, Goldberg L, Kuehl KS, Moe
EL, Breger RKR, Pickering MA. The
PHLAME (Promoting Healthy Lifestyles:
Alternative Models’ Effects) fi refi ghter
study: outcomes of two models of
behavior change. J Occup Environ Med.
2007;49(2):204–213
30. Hardcastle SJ, Taylor AH, Bailey MP,
Harley RA, Hagger MS. Effectiveness
of a motivational interviewing
intervention on weight loss, physical
activity and cardiovascular disease
risk factors: a randomised controlled
trial with a 12-month post-intervention
follow-up. Int J Behav Nutr Phys Act.
2013;10:40
31. Collins RL. Relapse prevention for
eating disorders and obesity. In:
Marlatt GA, Donovan DM, eds. Relapse
Prevention: Maintenance Strategies in
the Treatment of Addictive Behaviors.
New York: Guilford Press; 2005:248–275
32. Fjeldsoe B, Neuhaus M, Winkler E, Eakin
E. Systematic review of maintenance
of behavior change following physical
activity and dietary interventions.
Health Psychol. 2011;30(1):99–109
33. Fröhlich G, Pott W, Albayrak Ö,
Hebebrand J, Pauli-Pott U. Conditions
of long-term success in a lifestyle
intervention for overweight and
obese youths. Pediatrics. 2011;128(4.
Available at: www. pediatrics. org/ cgi/
content/ full/ 128/ 4/ e779
34. Goldschmidt AB, Best JR, Stein RI,
Saelens BE, Epstein LH, Wilfl ey DE.
Predictors of child weight loss and
maintenance among family-based
treatment completers. J Consult Clin
Psychol. 2014;82(6):1140–1150
35. Prochaska JO, DiClemente CC.
The transtheoretical approach.
In: Norcross JC, Goldfried MR,
eds. Handbook of Psychotherapy
Integration. New York: Oxford
University Press; 2005
36. Quattrin T, Roemmich JN, Paluch R,
Yu J, Epstein LH, Ecker MA. Treatment
outcomes of overweight children and
parents in the medical home. Pediatrics.
2014;134(2). Available at: www. pediatrics.
org/ cgi/ content/ full/ 134/ 2/ e290
37. Collins CE, Okely AD, Morgan PJ, et al.
Parent diet modifi cation, child activity,
or both in obese children: an RCT.
Pediatrics. 2011;127(4). Available at:
www. pediatrics. org/ cgi/ content/ full/
127/ 4/ e619
38. Reinehr T, Kersting M, Alexy U, Andler
W. Long-term follow-up of overweight
children: after training, after a single
consultation session, and without
treatment. J Pediatr Gastroenterol
Nutr. 2003;37(1):72–74
39. Bocca G, Corpeleijn E, van den Heuvel
ER, Stolk RP, Sauer PJ. Three-year
follow-up of 3-year-old to 5-year-
old children after participation in
a multidisciplinary or a usual-care
obesity treatment program. Clin Nutr.
2014;33(6):1095–1100
40. Wilfl ey DE, Stein RI, Saelens BE, et al.
Effi cacy of maintenance treatment
approaches for childhood overweight:
a randomized controlled trial. JAMA.
2007;298(14):1661–1673
10 by guest on October 20, 2020www.aappublications.org/newsDownloaded from
DOI: 10.1542/peds.2015-1979 originally published online December 23, 2015; 2016;137;Pediatrics
Tamelli, Silvia Candela, Eletta Bellocchio and Paolo Giorgi RossiFerrari, Gino Montagna, Costantino Panza, Mirco Pinotti, Simone Storani, Marco Serena Broccoli, Anna Maria Davoli, Laura Bonvicini, Alessandra Fabbri, Elena
of a Randomized Controlled TrialMotivational Interviewing to Treat Overweight Children: 24-Month Follow-Up
ServicesUpdated Information &
http://pediatrics.aappublications.org/content/137/1/e20151979including high resolution figures, can be found at:
Referenceshttp://pediatrics.aappublications.org/content/137/1/e20151979#BIBLThis article cites 26 articles, 5 of which you can access for free at:
Subspecialty Collections
http://www.aappublications.org/cgi/collection/obesity_new_subObesityhttp://www.aappublications.org/cgi/collection/child_care_subChild Carefollowing collection(s): This article, along with others on similar topics, appears in the
Permissions & Licensing
http://www.aappublications.org/site/misc/Permissions.xhtmlin its entirety can be found online at: Information about reproducing this article in parts (figures, tables) or
Reprintshttp://www.aappublications.org/site/misc/reprints.xhtmlInformation about ordering reprints can be found online:
by guest on October 20, 2020www.aappublications.org/newsDownloaded from
DOI: 10.1542/peds.2015-1979 originally published online December 23, 2015; 2016;137;Pediatrics
Tamelli, Silvia Candela, Eletta Bellocchio and Paolo Giorgi RossiFerrari, Gino Montagna, Costantino Panza, Mirco Pinotti, Simone Storani, Marco Serena Broccoli, Anna Maria Davoli, Laura Bonvicini, Alessandra Fabbri, Elena
of a Randomized Controlled TrialMotivational Interviewing to Treat Overweight Children: 24-Month Follow-Up
http://pediatrics.aappublications.org/content/137/1/e20151979located on the World Wide Web at:
The online version of this article, along with updated information and services, is
by the American Academy of Pediatrics. All rights reserved. Print ISSN: 1073-0397. the American Academy of Pediatrics, 345 Park Avenue, Itasca, Illinois, 60143. Copyright © 2016has been published continuously since 1948. Pediatrics is owned, published, and trademarked by Pediatrics is the official journal of the American Academy of Pediatrics. A monthly publication, it
by guest on October 20, 2020www.aappublications.org/newsDownloaded from