Abstract
BACKGROUND
This study seeks to determine whether antihypertensive medication refill adherence, ambulatory visits, and type of antihypertensive medication exposures are associated with decreased stroke and death for community-dwelling hypertensive patients.
METHODS
This retrospective cohort study included all chronic medication-treated hypertensives enrolled in Tennessee’s Medicaid program (TennCare) for 3–7 years during the period 1994–2000 (n = 49,479). Health care utilization patterns were evaluated using administrative data linked to vital records during a 2-year run-in period and 1- to 5-year follow-up period. Antihypertensive medication refill adherence was calculated using pharmacy records.
RESULTS
Associations with stroke and death were assessed using Cox proportional hazards modeling. Stroke occurred in 619 patients (1.25%) and death in 2,051 (4.15%). Baseline antihypertensive medication refill adherence was associated with decreased multivariate hazards of stroke [hazard ratio (HR) 0.91; 95% confidence interval (CI), 0.86–0.97 for 15% increase in adherence]. Adherence in the follow-up period was associated with decreased hazards of stroke (HR 0.92; CI 0.87–0.96) and death (HR 0.93; CI 0.90–0.96). Baseline ambulatory visits were associated with decreased death (HR 0.99; CI 0.98–1.00). Four major classes of antihypertensive agents were associated with mortality reduction. Only thiazide-type diuretic use was associated with decreased stroke (HR 0.89; CI 0.85–0.93).
CONCLUSIONS
Ambulatory visits and antihypertensive medication exposures are associated with reduced mortality. Increasing adherence by one pill per week for a once-a-day regimen reduces the hazard of stroke by 8–9% and death by 7%.
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Acknowledgments
This research was supported by a grant from the American Heart Association. The authors gratefully acknowledge the assistance of the TennCare Bureau of the State of Tennessee, Catherine Lewis and Deborah Gibson for their substantial editorial assistance, Grant Somes, PhD, and Andy Bush, PhD, for their assistance with the study design and analysis plan, and William Pulsinelli, MD, for contributing his advice and content expertise on the design and implementation of the study.
Conflicts of Interest
Dr. James Bailey has received a grant from Novo Nordisk, Inc., for reporting on diabetes quality of care, 2006–2008.
Jun Tang has been employed by Accredo Health Group, Inc., since 2007.
Dr. William Cushman has consulted for Sanofi-Aventis, Bristol-Myers Squibb, Novartis, Pfizer, Daiichi Sankyo, Forest, King Pharmaceuticals, Boehringer-Ingelheim, Roche, Takeda, Sciele, Pharmacopeia, and Gilead. He has received grants from Astra-Zeneca, Sanofi-Aventis, King, GlaxoSmithKline, and Novartis. He has a grant request pending with GlaxoSmithKline.
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Data for this study were also used in the following
Poster presentation. Academy Health, Washington DC, June 9, 2008. Bailey JE, Wan JY, Tang J, Ghani MA, Cushman WC. Antihypertensive medication adherence protects community dwelling hypertensive people from strokes and death.
Tang, J, Wan, JY, and Bailey, JE. Performance of comorbidity measures to predict stroke and death in a community-dwelling, hypertensive Medicaid population. Stroke 2008;39:1938–1944.
This research was supported by a grant from the American Heart Association.
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Bailey, J.E., Wan, J.Y., Tang, J. et al. Antihypertensive Medication Adherence, Ambulatory Visits, and Risk of Stroke and Death. J GEN INTERN MED 25, 495–503 (2010). https://doi.org/10.1007/s11606-009-1240-1
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DOI: https://doi.org/10.1007/s11606-009-1240-1