Selection of antihypertensive drug treatment in primary health care

BACKGROUND: To assess whether patients' clinical characteristics, and more specifically contraindications to diuretics or beta-blockers have an influe nce on the prescription patterns of antihypertensive drugs. PATIENTS AND METHODS: Cross-sectional descriptive study of consecutive hype rtensive patients attending 28 Primary Health Care Centres in Barcelona bet ween November 1997 and February 1998. Information on patients' clinical cha racteristics and prescribed antihypertensive and other drugs was recorded. Hyperuricemia, a previous adverse drug reaction and potential drug interact ions were considered as contraindications to diuretics. Asthma, chronic obs tructive airways disease, peripheral arteriopathy, bradycardia, atrio-ventr icular blockade, type 1 diabetes, a previous adverse drug reaction, and pot ential drug interactions were considered as contraindications to beta-block ers. RESULTS: Eighty-three general practitioners and 29 nurses collected data on 1,813 patients (66% were women and mean age was 68 years). Dislipemia was present in 746 patients (41.1%), diabetes in 385 (21.2%), hyperuricemia in 251 (13.8%), coronary heart disease in 218 (12%), and heart failure in 128 (7.1%). Diuretics were contraindicated in 350 patients (19.3%) and beta-blo ckers in 537 (29.6%). Eight-hundred seventy-nine patients (48.5%) were pres cribed an angiotensin-converting-enzyme (ACE) inhibitor, 803 (44.3%) a diur etic, 521 (28.7%) a calcium-channel blocker, and 246 (13.6%) a beta-blocker . The prescription pattern was similar in both patients with existing contr aindications to diuretics or beta-blockers, or without them, and in those w ith and without diabetes, heart failure or coronary heart disease and in th ose whose clinical characteristics would make the prescription of a diureti c, a beta-blocker or an ACE-inhibitor a first choice option. Prescription o f a diuretic was associated to age and to existing contraindications to a b eta-blocker, whereas the prescription of a beta-blocker was associated with a history of coronary heart disease. CONCLUSIONS: The present study suggests that contraindictions to diuretics or beta-blockers are not considered when prescribing antihypertensive drugs . The results of clinical trials are not applied to clinical practice, and this results in a high proportion of patients not being offered the benefit of cardiovascular risk prevention.