Racial/Ethnic Disparities in Medication Use Among Veterans with Hypertension and Dementia: A National Cohort Study

Abstract

Background: Hypertension and comorbid dementia are common illnesses affecting older adults disproportionally. Medication adherence is vital in achieving therapeutic outcomes. Use of antihypertensive and dementia medications may vary by race/ethnicity and has not been well explored. Objective: To evaluate the utilization of antihypertensive and dementia drugs and adherence in a national cohort of veterans aged 65 years or older with a diagnosis of both hypertension and dementia across different racial/ethnic groups. Methods: This was a retrospective cohort study that used 2 national databases of the Veterans Health Administration to estimate medication utilization and adherence rates among whites, African Americans, and Hispanics from 2000 to 2005. A medication possession ratio of 0.8 or greater defined adherence. The association between race/ethnicity and adherence was analyzed using multivariate logistic regression analysis. Results: A total of 56,561 patients (70.5% white, 15.6% African American, 6.6% Hispanic) aged 65 years or older had diagnoses of dementia and hypertension. African Americans were less likely than whites to receive angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), β-blockers, acetylcholinesterase inhibitors, and memantine (p < 0.05). Hispanics were more likely than whites to be prescribed an ACE inhibitor and less likely to be prescribed an ARB, β-blocker, nondihydropyridine calcium-channel blocker (CCB), loop diuretic, β-agonist, or potassium-sparing diuretic (PSD) (p < 0.05). Medication adherence was significantly lower in African Americans than whites in all classes except for ARBs, loop diuretics, and PSDs (p < 0.05). Being Hispanic was associated with significantly lower adherence rates than whites for dihydropyridine CCBs and acetylcholinesterase inhibitors (p <0.05). Conclusions: Racial/ethnic differences exist in antihypertensive and dementia medication use in a cohort of older adults with hypertension and dementia. Adherence rates for a number of antihypertensive and dementia drugs are lower for minorities compared with whites. Healthcare providers should make special efforts to improve medication adherence among minorities.