Associations between joblessness and oral anti-diabetic medication adherence in US diabetic working-age adults

OBJECTIVE: To assess potential associations between joblessness and oral anti-diabetic (OAD) medication adherence in US diabetic working-age adults. STUDY DESIGN: A retrospective longitudinal panel design used pooled 2001-2007 Medical Expenditure Panel Survey (MEPS) data forming a nationally representative sample of diabetic individuals, ages 24-59 years. Pregnancy, seasonal job status, retired persons, a student designation, and those prescribed insulin were excluded. Adherence was measured using the proportion of days covered (PDC). A PDC $0.80 was classified as adherent. Descriptive statistics and multivariate regression analysis accounting for the MEPS' complex survey design were conducted. RESULTS: There were 2256 individuals (means: age 48.3 years [SD 8.15], body mass index 31.1 [SD 0.30], Charlson Comorbidity Index 0.37 [SD 0.79]) who met study criteria. Thirty-four percent were jobless at the first interview round and 29% remained jobless all 5 interview rounds during the 2-year panel period. Reasons cited for joblessness included: waiting to start a new job (73%) and unable to work due to illness or disability (20%). Negligible proportions cited staying home to care for family members or maternity leave as reasons for joblessness. Proportionately, more individuals were nonadherent (55%, SE 0.006). Joblessness was associated with a 16% significant reduction in the PDC (β -15.9, P < 0.001), and a 25% less likelihood of OAD medication adherence compared with those employed (odds ratio 0.75; 95% confidence interval, 0.64-0.90, P = 0.002), while holding all other variables constant. CONCLUSIONS: The results indicate that jobless working-age individuals with diabetes were significantly less likely to adhere to OAD medication than employed individuals. © 2012 Elsevier Inc.