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Antihypertensive Medication Adherence, Ambulatory Visits, and Risk of Stroke and Death

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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.

Author information

Authors and Affiliations

  1. Division of General Internal Medicine, Department of Medicine, University of Tennessee Health Science Center, 956 Court Avenue, Coleman D222, Memphis, TN, 38163, USA

    James E. Bailey MD, MPH

  2. Department of Preventive Medicine, University of Tennessee Health Science Center, 66 N. Pauline, Suite 633, Memphis, TN, 38105, USA

    James E. Bailey MD, MPH, Jim Y. Wan PhD & William C. Cushman MD

  3. Accredo Health Group, Inc., 1640 Century Center Parkway, Memphis, TN, 38134, USA

    Jun Tang MS

  4. Department of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA

    Muhammad A. Ghani MD & William C. Cushman MD

  5. Preventive Medicine Section, Veterans Affairs Medical Center, 1030 Jefferson Avenue, Memphis, TN, 38104, USA

    William C. Cushman MD

Authors
  1. James E. Bailey MD, MPH
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  2. Jim Y. Wan PhD
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  3. Jun Tang MS
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  4. Muhammad A. Ghani MD
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  5. William C. Cushman MD
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Corresponding author

Correspondence to James E. Bailey MD, MPH.

Additional information

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

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