Introduction

A comprehensive, multidimensional geriatric assessment ofthe frail elderly is important so that appropriate plans fortreatment and follow-up care can be developed (1). Assessmentshould encompass evaluation of activities of daily living(ADLs), instrumental activities of daily living, mental stateincluding evidence of depression, balance/gait status, andnutritional status (2).

Poor nutritional status is a common and severe problem ininstitutionalized older adults, with prevalence reaching as highas 65% (3). Poor nutritional status has been shown to beassociated with increased medical expenses and mortality rates(4), and has been found to independently affect the duration ofhospital stay, the incidence of infections and pressure sores, thedegree of wound healing, the rate of readmission, and thedegree of cognitive dysfunction (5, 6).

According to the Nutrition Screening Initiative, risk factorsthat are associated with an increased likelihood of poornutritional status include psychosocial factors such asdepressive symptoms and physical factors such as decreasedmobility (5). Other risk factors that have been identified inprevious studies include disease (5-7) and impairment of ADLs(6). A strong connection between depressive symptoms andnutritional status has also been found among the elderly livingat home (7, 8).

Depressive symptoms are common among institutionalizedolder adults, with prevalence rates reaching as high as 45% (9).Depressive symptoms, however, very often remainundiagnosed and, therefore, untreated (9). A few studies havedemonstrated that depression is a major factor contributing topoor nutritional status among elderly people (10, 11). However,it remains unclear whether depression in nursing-homeresidents is the cause or consequence of poor nutritional status.

The prevalence of depressive symptoms is particularly highamong residents with low levels of physical activity, residentswith impairment in ADLs (9), and residents with poornutritional status (6). In a prospective longitudinal studyconducted between 2001 and 2006, Guigoz found that theprevalence of malnutrition increased with physical dependence(2). To date, no studies have explored the causal associationamong physical ability and depression and nutritional status inolder adults who reside in LTC institutions.

Therefore, the purposes of this study were to explore theextent that ADLs affect depressive symptoms and nutritionalstatus and to test whether depressive symptoms mediate theeffect of ADLs on nutritional status.

Methods

Design and research participantsIn this cross-sectional study, we used a purposive sampling

technique to select study facilities from among 307 community-based LTC facilities registered in a database provided by theDepartment of Social Welfare in Taipei in 2008. Afterexplaining the aims of this study to the owners andadministrators of the facilities, a total of 73 facilities agreed toparticipate, which represent approximately 24% of LTCfacilities in Taipei. The resident population of the 73 facilitieswas 2028 and the average number of residents in each facilitywas 28 (range, 10-46). The inclusion criteria for the participantsincluded a normal cognitive status, which was tested by theShort Portable Mental Status Questionnaire (SPMSQ), and theability to verbally communicate. Residents with SPMSQ scores< 7, indicating cognitive confusion, were excluded. Afterexplaining the purposes of this study, 306 residents from 73facilities met the sampling criteria for this study and voluntarilyagreed to participate. The participants represented

THE MEDIATING EFFECTS OF DEPRESSIVE SYMPTOMS ON NUTRITIONALSTATUS OF OLDER ADULTS IN LONG-TERM CARE FACILITIES

I.-C. LI, H.-T. KUO, Y.-C. LIN

Institute of Clinical and Community Health Nursing, Taipei, Taiwan. Corresponding author: I-chuan Li, icli@ym.edu.tw

Abstract: Objective: To test whether depressive symptoms mediate the effects of activities of daily living(ADLs) on nutritional status of older adults living in long-term care (LTC) facilities in Taiwan. Design: A cross-sectional study. Setting: Seventy-three community-based LTC facilities in northern Taiwan. Participants: Thisstudy sampled 306 adults ranging in age from 65 to 97 years who were free of acute infection or disease and whowere able to communicate. Measurements: Nutritional status was assessed by the Mini-Nutritional Assessment(MNA) scale and depressive symptoms were assessed by the short form of the Geriatric Depressive Scale (GDS-SF). Results: MNA scores revealed that 65% of the subjects were at risk for malnutrition (17 to 23.5 points). Inaddition, depressive symptoms partially mediated the relationship between ADLs and nutritional status, with10.7% of the effect of depressive symptoms on nutritional status going through the mediator. Conclusion:Interventions to reduce depressive symptoms among institutionalized older adults should focus on improvingnutritional status rather than promoting ADLs, which are believed to be difficult to change.

Key words: Depressive symptoms, institutionalized older adults, mediating effect, nutritional status.

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approximately 15% of all residents of the 73 facilities.

Study instruments

Short Portable Mental Status Questionnaire The SPMSQ was used to assess residents’ cognitive function

(12). The assessment includes 10 questions divided among fourdomains: orientation (3 items), personal history (3 items),remote memory (3 items), and calculation (1 item). Scoresranging from 0 to 2 indicate severe cognitive impairment, thoseranging from 3 to 5 indicate moderate cognitive impairment,scores ranging from 6 to 7 indicate mild cognitive impairment,and scores ranging from 8 to 10 indicate intact cognitivefunction.

Nutritional assessmentThe investigator assessed subjects’ nutritional status by

using the Mini Nutritional Assessment (MNA) scale, which isone of the most widely used tools for assessing nutritional riskin institutionalized populations or at-risk older adults in Europeand the U.S.A (13). Chen et al. used the MNA to assessnutritional status among older Taiwanese adults (7).

The first part of the MNA consists of anthropometricmeasurements, including body height, body weight, weight lossduring the past 3 months, calf circumference, and mid-armcircumference. The body length of bedridden patients wasestimated by measuring the participants’ knee height using anestablished formula (14). Mid-arm circumference wasmeasured midway between the lateral projection of theacromion process of the scapula and the inferior margin of theolecranon process of the ulna.

The second part of the MNA includes six global questionsregarding accommodation type, pharmaceutical use, acutediseases, mobility, neuropsychological problems, and pressuresores/skin ulcers. The third part of the MNA consists of sixquestions that assess dietary intake (e.g., how many wholemeals are eaten), food choices, fluid intake per day, andwhether help is required during meals. Fluid intake wasassessed by determining how many glasses (240 ml) of fluid theresidents drank per day. The answers yield a maximum of 30points. Scores below 17 points indicate malnutrition, scoresbetween 17 and 23.5 points indicate a risk for malnutrition, andscores above 23.5 points indicate that the person is wellnourished.

Modified Barthel Index ADL scores were determined using the modified Barthel

Index, which consists of 10 items: eating, bathing, cleaning,dressing, personal hygiene, toilet ability, moving, walking, andgoing up and down stairs. It was developed by Shah et al. fromthe original Barthel Index by modifying the scoring method toincrease test sensitivity (15). Total scores range from 0 to 100:0 to 20 indicates total dependence, 21 to 60 indicates severedependence, 61 to 90 indicates moderate dependence, 91 to 99

indicates slight dependency, and 100 indicates functionalindependence.

Assessment of depressive symptoms Depressive symptoms were evaluated using the short form of

the Geriatric Depressive Scale (GDS-SF). Sheikh and Yesavagedeveloped the 15-item brief version of the GDS using itemsfrom the original tool (30 items) that showed the highestcorrelation with depression (16). The GDS-SF has been used tomeasure depressive symptoms among Taiwanese of advancedage and the reliability and validity of the scale have beenconfirmed (17). The GDS-SF includes 15 items with scoresranging from 0-15; a score ranging from 0 to 4 indicates nodepressive symptoms; scores ranging from 5 to 9 representpossible clinical depressive symptoms; and scores ranging from10 to 15 indicate severe depressive symptoms (18).

Data collection procedureThe data were collected by an investigator who was trained

by the study’s principal investigator. The investigator used theSPMSQ to select residents with intact cognitive function beforeassessing depressive symptoms. Subsequently, the GDS-SF andthen the MNA were completed.

The nurses at each facility provided the investigator withinformation regarding daily routines related to dietaryrequirements and meal management, such as estimations of theamount of food eaten. Socio-demographic characteristics,ADLs status, and medical diagnoses were retrieved by theinvestigator from the medical records.

Data analysis The Sobel test was used to identify the mediating effects of

depressive symptoms on nutritional status. All statisticalanalyses were performed with the statistical package SPSS forWindows (Version 18.0, SPSS Inc., Chicago, IL, USA)

Ethical considerationsThis study was approved by the Institutional Review Board

of the National Yang-Ming University. All of the participants inthe study participated voluntarily and provided informedconsent.

Results

Characteristics of the study participantsAll of the 306 participants completed the study. The mean

age of the subjects was 80.6 years (SD =7.1; range 65.1- 96.6years) and the mean number of chronic diseases per participantwas 2.6 (SD =1.2). Approximately one-third of the participants(n=100, 32.7%) had Barthel Index scores ranging from 61 to90, indicating that they were moderately functionallydependent, and approximately half of the participants (n=166,54.2%) had GDS-SF scores of 5 or greater, indicating that theyrequire further evaluation by a psychiatric specialist (17).

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Furthermore, 5.9% of the participants were malnourished(MNA 4 years 71 (23.3)

ADLs 61.3 (31.9) 0-100Total dependency 58 (19.0)Severe dependency 83 (27.1)Moderate dependency 100 (32.7)Slight dependency 32 (10.5)Independency 33 (10.8)

GDS-SF score 5.9 (4.2) 0-15Normal (0-4 points) 135 (44.1)Possible depression (5-9 points) 90 (29.4)Depression (10-15 points) 76 (24.8)

MNA score 21.7 (3.2) 12.0-28.5 23.5 80 (26.1)

Triceps skinfold thickness (mm) 11.8 (4.6) 3.2-37.0 Mid-arm circumference (cm) 26.3 (3.7) 12.7-43.0Calf circumference (cm) 30.9 (3.8) 18.5-44.3

ADL, activities of daily living; SD, standard deviation; GDS-SF, geriatric depressionscale-short form. MNA, Mini Nutritional Assessment; SD, standard deviation.

Nutritional status and correlated factors during thescreening evaluations

The mean number of chronic diseases, mean ADL score, andmean GDS-SF score were significantly correlated with MNAscore (r = -0.13, 0.51, and -0.35, respectively). Aftercontrolling for age, gender, ADL score, and number of chronicdiseases, multi-nominal logistic regression analysis revealedthat GDS-SF score was a significant predictor of malnutritionstatus (MNA < 17) (OR = 1.23, p < 0.01, 95% CI = 1.05-1.44)and at-risk-of-malnutrition status (17-23.5) (OR = 1.21, p <

0.001, 95% CI = 1.10-1.33). To understand the differencesamong groups with different ADL scores and GDS scores afterremoving the items of mobility and neuropsychogical problemsfrom the MNA, ANOVA and the t-test were used. The resultsof ANOVA and the t-test revealed that there were significantdifferences in nutritional status between residents with differentADL scores (t =-4.68, p < 0.001), and GDS scores (F = 17.64,p < 0.001) after removing the items of mobility andneuropsychogical problems from the MNA (Table 2).

The mediating effects of depressive symptoms onnutritional status

We found that ADLs were significantly associated withdepressive symptoms (β = -0.213, p < 0.001). We also foundthat ADLs were significantly associated with nutritional status(β = 0.511, p < 0.001). For example, depressive symptomssignificantly predicted nutritional status (β =-0.254, p < 0.001),and when depressive symptoms were included in the equation,there was a significant reduction in the relationship betweenADLs and nutritional status (β =0.456, p < 0.001). Finally, asignificant relationship in the Sobel test was noted (z =3.02, p =0.003), indicating that depressive symptoms partially mediatedthe relationship between ADLs and nutritional status, with10.7% of the effect of depressive symptoms on nutritionalstatus going through the mediator. In other words, depressivesymptoms can decrease the effect of ADLs on nutritional status(Figure 1).

Figure 1Mediation models of components of the depressive symptoms

on the relationship between ADL and nutritional status

***p

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lives (22). In other LTC institutions in Europe and NorthAmerica, malnutrition rates (as measured by the MNA) havebeen found to range from 5%-70%, which indicates thatnutritional risk varies widely across residential care settings indifferent countries (23).

Table 2 Multi-nominal logistic regression of selected subjects’

demographic variables, health status, and depressive symptoms(N = 296)

Variable B SE Odds ratio OR (95% CI)

Malnourished ( 23.5). B,Coefficient of logistic regression; OR, odds ratio; CI, confidence interval; GDS-SF,geriatric depression scale-short form; ADL, activities of daily living. Model fitting criteria:-2 log likelihood=378.35. **P < 0.01; *** P < 0.001.

The prevalence of depressive symptoms (54.2%) as assessedby the GDS-SF in this study was higher than that reported in aprevious study in Taiwan (24). It is also higher than thatreported for a similar elderly population (24, 25). Depressivesymptoms very often remain undiagnosed and, therefore,untreated.

Results of the Sobel test in this study revealed that, to reducemalnutrition status among institutionalized older adults,interventions should focus on alleviating depressive symptomsrather than promoting daily living activities, which are believedto be difficult to change. Causes of malnutrition in depressedpatients mainly involve lack of appetite, apathy, and physicalweakness (6). We found that the MNA is a sensitive assessmentand can be influenced by the degree of depression amongsubjects.

Health professionals in LTC facilities should, therefore,assess residents’ depressive symptoms and provideinterventions focusing on alleviating depressive symptoms inorder to prevent malnutrition. Thomas et al. found that theeffects of treatment for depressive symptoms on nutrition statusin elderly out-patients were weight gain and improved MNAscores (26). Longitudinal studies should be conducted in LTCfacilities to assess the effect of depression treatment onnutritional status.

Study limitationsThe limitations of this study included the cross-sectional

design and the non-random selection of residents, which limits

the ability to generalize the results of our study.

Conclusion

Depressive symtoms is a significant mediator between ADLsand nutrition status among older adults who reside incommunity-based LTC facilities in northern Taiwan. Thisfinding can help health professionals initiate appropriatestrategies to improve depressive symptoms in order to preventmalnutrition.

Acknowledgments: Funding for the research was provided by the Taipei VeteransGeneral Hospital, Taiwan (V97D-002). The authors would like to thank the 306 residentsof the LTC facilities who participated in this study.

Conflict of interest statement: The authors declare no conflicts of interest.

References1 Ellis G, Langhorne P (2005) Comprehensive geriatric assessment for older hospital patients. Br

Med Bull 71:45-59.2 Guigoz Y (2006) The Mini Nutritional Assessment (MNA®) review of the literature-what does

it tell us? J Nutr Health Aging 10:466-487.3 Smoliner C, Norman K, Wagner KH, Hartig W, Lochs H, Pirlich M (2009) Malnutrition and

depression in the institutionalised elderly. Br J Nutr 102:1663-1667.4 Chang HT, Liu LF, Chen CK, Hwang SJ, Chen LK, Lu FH (2010) Correlates of institutionalized

senior veterans' quality of life in Taiwan. Health Qual Life Outcomes 8:70.5 Nutrition Screening Initiative (2004) Incorporating nutrition screening and intervention into

medical practice. Nutrition Screening Initiative, Washington, DC.6 Payette H (2005) Nutrition as a determinant of functional autonomy and quality of life in aging:

A research program. Can J Physiol Pharmacol 83:1061-1070.7 Chen LK, Lin MH, Hwang SJ, Wang P, Chwang LC (2007) Nutritional status and clinical

outcomes among institutionalized elderly chinese in taiwan. Arch Gerontol Geriatr 44:315-323.8 Johansson Y, Bachrach-Lindstrom M, Carstensen J, Ek AC (2009) Malnutrition in a home living

older population: Prevalence, incidence and risk factors. A prospective study. J Clin Nurs18:1354-1364.

9 Webber AP, Martin JL, Harker JO, Josephson KR, Rubenstein LZ, Alessi CA (2005)Depression in older patients admitted for postacute nursing home rehabilitation. J Am Geriatr Soc53:1017-1022.

10 Cabrera MAS, Mesas AE, Garcia ARL, de Andrade SM (2007) Malnutrition and depressionamong community-dwelling elderly people. J Am Med Dir Assoc 8:582-584.

11 German L, Feldblum I, Bilenko N, Castel H, Harman-Boehm I, Shahar DR (2008) Depressivesymptoms and risk for malnutrition among hospitalized elderly people. J Nutr Health Aging12:313-318.

12 Pfeiffer E (1975) A short portable mental status questionnaire for the assessment of organic braindeficit in elderly patients. J Am Geriatr Soc 23:433-441.

13 Guigoz Y, Lauque S, Vellas BJ (2002) Identifying the elderly at risk for malnutrition the mininutritional assessment. Clin Geriatr Med 18:737-757.

14 Haboubi NY, Hudson PR, Pathy MS (1990) Measurement of height in the elderly. J Am GeriatrSoc 38:1008-1010.

15 Shah S, Vanclay F, Cooper B (1989) Improving the sensitivity of the barthel index for strokerehabilitation. J Clin Epidemiol 42:703-709.

16 Sheikh JA, Yesavage JA (1986) Geriatric Depression Scale (GDS): Recent findings anddevelopment of a shorter version. In: Brink TL (ed) Clinical gerontology: A guide to assessmentand intervention. Howarth Press, New York, pp 165-173.

17 Liao YC, Yeh TL, Ko HC, Luo ZM, Lu FH (1995) The short form of geriatric depression scale(GDS-SF)–a preliminary report of reliability and validity for chinese version. The ChanghuaJournal of Medicine (in Chinese) 1:11-17.

18 Lee HCB, Chiu HFK, Kowk WY, Leung CM, Kwong PK, Chung DWS (1993) Chinese elderlyand the GDS short form: A preliminary study. Clin Gerontol 14:37-42.

19 Ministry of the Interior (2012) Population by Single Year of Age. Ministry of the Interior, Taipei. 20 Huang JJ, Lin KC, Li IC (2008) Service needs of residents in community-based long-term care

facilities in northern taiwan. J Clin Nurs 17:99-108.21 Tsai AC, Lai MC, Chang TL (2012) Mid-arm and calf circumferences (MAC and CC) are better

than body mass index (BMI) in predicting health status and mortality risk in institutionalizedelderly taiwanese. Arch Gerontol Geriatr 54:443-447.

22 Hsieh YM, Sung T, Wan KS (2010) A survey of nutrition and health status of solitary and non-solitaty elders in Taiwan. J Nutr Health Aging 14: 11-14.

23 Cereda E (2012) Mini nutritional assessment. Curr Opin Clin Nutr Metab Care 15:29-41.24 Lin IC, Yu SM, Chang HJ (2004) A survey of depression and its related factors of the

institutionalized and non-institutionalized elderly in Hsin-Tien city. Taiwan J Fam Med 14:81-93.25 Ruckdeschel K, Thompson R, Datto CJ, Streim JE, Katz IR (2004) Using the minimum data set

2.0 mood disturbance items as a self-report screening instrument for depression in nursing homeresidents. Am J Geriatr Psychiatry 12:43-49.

26 Thomas P, Hazif-Thomas C, Clement JP (2003) Influence of antidepressant therapies on weightand appetite in the elderly. J Nutr Health Aging 7:166-171.

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