Connie A. Mah, M.S. Department of Ambulatory Care & Prevention

1. Racial Differences in the Impact of HMO Coverage of Diabetes Blood Glucose Monitors on Self-Monitoring Connie A. Mah, M.S. Department of Ambulatory Care & Prevention Harvard Medical School & Harvard Pilgrim Health Care cmah@fas.harvard.edu

2. Acknowledgements • Co-Authors: • Stephen B. Soumerai, ScD • Alyce S. Adams, PhD • Dennis Ross-Degnan, ScD • Funders: • AHRQ • Harvard Pilgrim Health Care Foundation • Consultants: • Fang Zhang, PhD • John D. Piette, PhD • James Meigs, MD, MPH

3. Background • Disparities in diabetes health & health care use • Blacks have worse glycemic control • Blacks at greater risk of adverse outcomes • Differences in diabetes quality of care & self-management • Blacks receive lower quality of care • Blacks face greater barriers to self-management

4. Coverage Policy • Objective • To reduce cost as a barrier • To increase access to high quality care • Mandated in over 38 states • Provision of glucose monitoring devices & supplies • Findings from parent evaluation study* • Increased rates of SMBG *Soumerai, Mah, Zhang, et al., Archives of Internal Medicine 2004 (164(6):645-52)

5. Key Research Questions • Does this policy have the potential to narrow some of the racial disparity in diabetes self-management? • Does providing free home glucose monitors have differential impacts on self-monitoring for black and white diabetes patients?

6. Purpose • To determine whether policy increased initial trials of self-monitoring among black versus white patients • To investigate whether patients who initiated self-monitoring after the policy continued to self-monitor thereafter

7. Research Design & Setting • Research Design • Longitudinal, retrospective cohort analysis • Study Setting • Harvard Vanguard Medical Associates (HVMA) • Harvard Pilgrim Health Care (HPHC)

8. HPHC Coverage Policy • Start of Implementation: Oct 1,1993 • Objective • To motivate diabetes patients to start monitoring their blood glucose • Policy Benefits • Provision of glucose monitoring devices • Self-management training & education • Lower copay for up to 3 months’ supply of test strips (≤$5/script)

9. Study Cohort • Definition of Diabetes: • ≥ 1 hospital discharge Dx; or • ≥ 2 outpatient Dx; or • ≥ 1 insulin or oral sulfonylurea Rx • Black or Whiterace only • Continuous enrollment (1992-1996) • N=2,275 adult patients

10. Race Identification Clinical Encounters HbA1c Lab Results Ambulatory Medical Records Dispensed Test Strips PATIENT STUDY ID Pharmacy Claims Drug Therapy Membership/ Enrollment Census File Home Address (linked by census block group) Demographic Info Days Enrolled HVMA Data Sources (1992-1996)

11. Key Measures • Main independent measure • Race (black v. white) • Outcome measures • Incidence of SMBG (≥1 strip) • Discontinuation of SMBG (>180 days w/out strips) • Covariates • Fixed(age, sex, census-derived median HH income & educational level, drug type, BMI, HbA1c test, primary health site) • Time-Varying (mean HbA1c values in prior month, # MD visits per month)

12. Main Analytical Methods • Kaplan-Meier & Log-Rank Tests • Cumulative rates of initiation of SMBG • Cumulative rates of discontinuation of SMBG • Extended Segmented Cox Models • Adjusting for patient-level fixed & time-varying covariates • Relative (hazard) rates of initiation of SMBG (blacks relative to whites)

13. Pre-Policy Patient Differences Bold denote p<0.05

14. Initiation of SMBG

15. phase-in phase-in % with SMBG • Black White

16. Controlling for age, glycemic control, time-dependent drug use, and time-dependent number of physician visits Censoring at first insulin use or never initiated SMBG * p <0.05

17. Discontinuation of SMBG

18. Post-Policy SMBG Initiators p<0.05 • Discontinuation = >180 days without test strip use

19. Summary • Trials of self-monitoring in post-policy  increase in SMBG  greater for blacks on oral therapy • Persistence after initiation of SMBG in post-policy  short-lived

20. Limitations • Missing race data • Important unmeasured factors • Socio-cultural factors (attitudes, perceptions, cultural beliefs/values) • Duration of illness • Intensity of medication use • Single HMO

21. Take Home Points • Coverage is effective in engaging patients in SMBG particularly blacks • Sustainability must be addressed • Additional interventions may be necessary to improve long-term adherence and clinical outcomes