Sex differences in antihypertensive drug use: determinants of the choice of medication for hypertension.
OBJECTIVE
To describe and explain sex differences in antihypertensive drug use.


METHODS
From 1987 to 1995, two cross-sectional population-based surveys of cardiovascular disease risk factors in The Netherlands were carried out among 56026 men and women aged 20-59 years. Polytomous logistic regression modelling was used to adjust for potential confounders of the association between sex and use of different antihypertensive drugs.


RESULTS
The response rate was 40% for men and 46% for women. Of these respondents, 40% (1041) of the hypertensive men and 59% (1403) of the hypertensive women were being treated pharmacologically; 57% (595) of the treated men and 54% (760) of the treated women were on monotherapy for hypertension with a diuretic (men 14.8%, women 37.2%), a beta-blocker (men 59.0%, women 45.3%), a calcium antagonist (men 8.6%, women 5.0%) or an angiotensin converting enzyme inhibitor (men 17.7%, women 12.5%). Among those on monotherapy for hypertension, women were less likely than men to be using a beta-blocker [prevalence odds ratio (POR), female/male=0.34; 95% confidence interval (CI) 0.24-0.47], a calcium antagonist (POR=0.27, 95% CI 0.15-0.48) or an angiotensin converting enzyme inhibitor (POR=0.34, 95% CI 0.22-0.52) than a diuretic. These sex differences persisted after adjustment for all factors that could have influenced the choice of these antihypertensive drugs (indications and contra-indications for the four antihypertensive drug classes). The sex differences in antihypertensive drug use were smaller among hypertensives with a history of cardiovascular disease (adjusted PORs, female/male, for beta-blockers, calcium antagonists and ACE inhibitors, respectively, compared to diuretics were 0.80 with 95% CI 0.20-3.24, 0.40 with 95% CI 0.10-0.48 and 0.64 with 95% CI 0.12-3.39) than among those without such a history.


CONCLUSIONS
The different patterns of antihypertensive drug use among hypertensive men and women seem irrational, and cannot be explained by factors known to influence antihypertensive drug choice. Among hypertensives with a history of cardiovascular disease, the sex differences were smaller than among those without such a history. Further research is required to explain the sex differences in the choice of antihypertensive drug by prescribers, and to investigate the consequences of these differences for long-term patient outcomes.
Klungel
O H
OH
Department of Pharmacoepidemiology and Pharmacotherapy, Faculty of Pharmacy, University of Utrecht, The Netherlands.
de Boer
A
A
Paes
A H
AH
Seidell
J C
JC
Bakker
A
A
D000328:Adult; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D002121:Calcium Channel Blockers / Q000627:therapeutic use; D003430:Cross-Sectional Studies; D004232:Diuretics / Q000627:therapeutic use; D004359:Drug Therapy, Combination; D004363:Drug Utilization / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D012189:Retrospective Studies; D012727:Sex Characteristics; D011795:Surveys and Questionnaires
D000806:Angiotensin-Converting Enzyme Inhibitors; D000959:Antihypertensive Agents; D002121:Calcium Channel Blockers; D004232:Diuretics