Noncompliance with antihypertensive medications
OBJECTIVE: Addressing the epidemic of poor compliance with antihypertensive medications will require identifying factors associated with poor adherence, including modifiable psychosocial and behavioral characteristics of patients.
DESIGN: Cross-sectional study, comparing measured utilization of antihypertensive prescriptions with patients’ responses to a structured interview.
STUDY POPULATION: Four hundred ninety-six treated hypertensive patients drawn from a large HMO and a VA medical center.
DATA COLLECTION: We developed a survey instrument to assess patients’ psychosocial and behavioral characteristics, including health beliefs, knowledge, and social support regarding blood pressure medications, satisfaction with health care, depression symptom severity, alcohol consumption, tobacco use, and internal versus external locus of control. Other information collected included demographic and clinical characteristics and features of antihypertensive medication regimens. All prescriptions filled for antihypertensive medications were used to calculate actual adherence to prescribed regimens in a 365-day study period.
MAIN OUTCOME OF INTEREST: Adjusted odds ratios (ORs) of antihypertensive compliance, based on ordinal logistic regression models.
RESULTS: After adjusting for the potential confounding effects of demographic, clinical, and other psychosocial variables, we found that depression was significantly associated with noncompliance (adjusted OR per each point increase on a 14-point scale, 0.93; 95% confidence interval [95% CI], 0.87 to 0.99); in unadjusted analyses, the relationship did not reach statistical significance. There was also a trend toward improved compliance for patients perceiving that their health is controlled by external factors (adjusted OR per point increase, 1.14; 95% CI, 0.99 to 1.33). There was no association between compliance and knowledge of hypertension, health beliefs and behaviors, social supports, or satisfaction with care.
CONCLUSIONS: Depressive symptoms may be an under-recognized but modifiable risk factor for poor compliance with antihypertensive medications. Surprisingly, patient knowledge of hypertension, health beliefs, satisfaction with care, and other psychosocial variables did not appear to consistently affect adherence to prescribed regimens.
Key wordsantihypertensive medication adherence depressive symptoms psychosocial factors
Unable to display preview. Download preview PDF.
- 9.Haynes RB. Determinants of compliance: the disease and the mechanics of treatment. In: Haynes RB, Taylor D, Sackett D, eds. Compliance in Health Care. Baltimore: Johns Hopkins University Press; 1979.Google Scholar
- 17.Haynes RB, Mattson M, Chobanian A, et al. Management of patient compliance in the treatment of hypertension. Report of the NHLBI Working Group. Hypertension. 1982;4:415–23.Google Scholar
- 18.Haynes RB. A critical review of the “determinants” of patient compliance with therapeutic regimens. In: Sackett DL, Haynes RB, eds. Compliance with Therapeutic Regimens, Johns Hopkins University Press; 1976.Google Scholar
- 20.Haines C, Ward G. Recent trends in public knowledge, attitudes, and reported behavior with respect to high blood pressure. Public Health Rep. 1981;96:515–22.Google Scholar
- 21.Earp J, Ory M. The effects of social support and health professional home visits on patient adherence to hypertension regimens. Prev Med. 1979;8:155–62.Google Scholar
- 23.Bittar N. Maintaining long-term control of blood pressure: the role of improved compliance. Clin Cardiol. 1995;18:(6 suppl 3)12–6.Google Scholar
- 37.SAS User’s Guide. Version 6.12. SAS Institute, Cary, N.C., 1998.Google Scholar
- 43.Meichenbaum D, Turk D. Facilitating Treatment Adherence. New York: Plenum; 1987.Google Scholar
- 46.Waxman HM, McCreary G, Weinrit RM, Carner EA. A comparison of somatic complaints among depressed and nondepressed older patients. Gerontologist. 1987;85:501–7.Google Scholar
- 49.Ley P. Doctor-patient communication: some quantitative estimates of the role of cognitive factors in non-compliance. J Hypertens. 1985;3(suppl 1):51–5.Google Scholar