Culture Conversion and Self-Administered Therapy in Privately Managed Tuberculosis

Patients

Melissa Ehman MPH, Jennifer Flood MD MPH, Pennan Barry MD MPH

Tuberculosis Control Branch, Division of Communicable Disease Control, Center for Infectious Diseases, California Department of Public Health

Background• Private medical providers (PMPs) provide majority of

care for 1/3 of patients with tuberculosis (TB) in California increasing trend as of 2009Affordable Care Act may further increase PMP role in

TB patient care

• Local health departments (LHDs) maintain responsibility for oversight

• Proportion of cases cared for by PMPs varies widely between LHDs, from 3% to 100%

• Differences in indicator results between LHD- and PMP-managed patients point to possible differences in care, and opportunities for improvement

Provider Types* in California, by LHD, 2003-2008

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%Alameda

Contra Costa

FresnoSacramento

Kern

Los AngelesMonterey

Orange

San Bernardino

San Diego

San Francisco

San Joaquin

San MateoSanta Clara

Stanislaus Tulare

Ventura

Yolo

HD %

PMP%

*proportion of patients cared for by both PMP and HD not shown

Objective

Determine whether patient characteristics explain indicator performance differences between patients managed by PMPs and LHDs

Methods• Study population: TB cases counted in California during

2003, 2004, 2005, 2006, 2008• Data sources: RVCT, and Office of AIDS Registry Match

Data for California• TB cases were stratified according to provider type

“LHD” or “PMP/Other”• Exclusions

– “Both” provider type: variation in reporting across LHDs– Diagnosed at death: provider type not routinely reported

• Associations between PMP care and indicator outcomes modeled using multivariable regression, adjusting for patient demographic and clinical characteristics

Study Indicators

First two indicators chosen for inclusion based on:– Public health impact of TB control activity– Known differences in results between PMP and LHD patients

on univariable analysis

1. Culture ConversionDocumented sputum culture conversion to negative within 70 days of treatment start, for sputum culture-positive TB patients who do not die during the first 70 days of treatment

2. Inappropriate Self-Administered Therapy (SAT)Patients receiving only SAT, of those starting treatment and for whom DOT is indicated under California guidelines:

AIDS, drug-resistance, previous TB, culture conversion >60 days, cavitary TB, sputum smear-positive TB, homelessness, drug use, age <18 years, recent incarceration

Results

No Documented Culture Conversion ≤70 DaysSelected Univariable Analysis Results

Patient Characteristic

All Patients

N (%)

No CC ≤70d n (%)

P value

ALL PATIENTS 6328 (100) 1850 (29) --

Age 0-4 years 7 (0.1) 5 (71) 0.026

Any MDR 74 (1.2) 30 (41) 0.030

PMP managed 1849 (29) 730 (39) <0.001

Disseminated disease 109 (1.7) 40 (37) 0.084

Cavitary disease 1712 (28) 580 (34) <0.001

Born in United States 1144 (18) 390 (34) <0.001

Homeless or drug/alcohol use 1155 (18) 379 (33) 0.003

HIV positive 148 (2.3) 45 (30) 0.752

Female 2238 (35) 584 (26) <0.001

DOT for ≥10 weeks 3935 (62) 951 (24) <0.001

No Documented Culture Conversion ≤70 DaysMultivariable Model Results

Patient CharacteristicRelative

Risk95% Confidence

Interval (CI)

Age 0-4 years 2.19 1.24 – 3.86

PMP managed 1.56 1.45 – 1.68

Any MDR 1.72 1.35 – 2.19

Disseminated disease 1.27 1.003 – 1.63

Cavitary disease 1.26 1.16 – 1.36

Homeless or drug/alcohol use 1.17 1.29 – 1.06

Born in United States 1.12 1.02 – 1.23

HIV positive 1.01 0.78 – 1.31

Female 0.87 0.80 – 0.95

DOT for ≥10 weeks 0.61 0.56 – 0.66

SAT in Patients with Indications for DOTSelected Univariable Analysis Results

Patient Characteristic

All Patients

N (%)

SATn (%)

P value

ALL PATIENTS 6824 (100) 746 (11) --

PMP managed 2271 (33) 568 (25) < 0.001

No culture conversion ≤ 60 days 2027 (42) 300 (15) <0.001

History of TB 622 (9.2) 78 (13) 0.174

INH or Rifampin resistance 783 (14) 97 (12) 0.128

Long-term care facility 213 (3.1) 23 (11) 0.948

HIV positive 201 (2.9) 17 (8.4) 0.254

Age < 18 years 863 (13) 70 (8.1) 0.005

Cavitary disease 1823 (29) 129 (7.1) <0.001

Sputum smear-positive 3839 (63) 212 (5.7) <0.001

Homeless or drug/alcohol use 1498 (22) 81 (5.4) <0.001

Correctional facility 204 (3.0) 10 (4.9) 0.005

SAT in Patients with Indications for DOTMultivariable Model Results

Patient Characteristic Odds Ratio 95% CI

PMP managed 8.45 8.84 – 11.44

No culture conversion ≤ 60 days 1.67 1.29 – 2.15

Born in United States 1.39 1.02 – 1.90

History of TB 0.77 0.49 – 1.20

Cavitary disease 0.52 0.39 – 0.70

INH or Rifampin resistance 0.48 0.31 – 0.74

Age < 18 years 0.46 0.22 – 0.97

HIV positive 0.45 0.18 – 1.14

Correctional facility 0.26 0.10 – 0.67

Homeless or drug/alcohol use 0.25 0.16 – 0.39

Smear positive 0.23 0.18 – 0.30

Long-term care facility 0.18 0.07 – 0.49

Disseminated disease 0.17 0.06 – 0.52

Summary

Documented Sputum Culture Conversion ≤ 70 Days• After adjustment for confounders, PMP-managed TB

patients less likely to culture convert, vs. LHD-managed • Patients with MDR TB or cavitary disease less likely to

document culture conversion ≤ 70 days• Patients receiving ≥ 10 weeks of DOT more likely to

document culture conversion ≤ 70 days

SAT When DOT Is Indicated• PMP-managed TB patients more likely to receive SAT

throughout treatment when DOT is indicated• Patients slow to culture convert more likely to receive

SAT, vs. those with other DOT indications

Limitations

• Preliminary results• Caution for interpretation at local level

– Reporting of provider type varies across LHDs– Influence of patient characteristics may also vary

• Unmeasured confounders, e.g., comorbidities and culture conversion

• Odds ratios are likely overestimates of magnitude of true associations

California Interventions to ImprovePMP-Managed TB Patient Care (1)

TB Indicators Project (TIP) • Partnership between state and 14 local TB control

programs with highest TB incidence in California• Culture Conversion and DOT/SAT among most-selected

indicators• Outcomes improved after TIP interventions in most LHDs

California Interventions to ImprovePMP-Managed TB Patient Care (2)

State TB Program Interventions• Fact sheets on DOT and culture conversion

– targeted to PMPs

LHD TB Program Interventions• Letter to PMP at diagnosis

– outlining standards of care and LHD role• Provide DOT and sputum collection for PMP patients• Regular case management conferences

– identify patients not on DOT or without documented culture conversion

Conclusions

When other characteristics are taken into account,

PMP-managed patients are at higher risk for:• not having a documented, timely culture conversion • receiving SAT when DOT is indicated

When TB patients cannot be managed by the LHD, strategies to ensure a consistent level of TB care for PMP patients are needed

Outcomes might improve by LHD overseeing culture conversion and providing DOT

Next Steps• Sensitivity analysis of culture conversion

within 70 vs. 60 days• Assess additional indicators of interest

• Completion of therapy, to inform feasibility of improving performance

• Deaths during therapy, to avert preventable deaths in the future

• Include new surveillance fields:• Comorbidities• Patients receiving only inpatient care

• Measure effectiveness of specific LHD interventions to improve outcomes for patients under PMP care

Acknowledgements

• Anne Cass• Alex Golden• Linda Johnson• Lisa Pascopella• Fei Fei Qin

For more information, please contact Melissa Ehman: mehman@cdph.ca.gov