Treating hypertension. Are the right drugs given to the right patients?
OBJECTIVE
To evaluate whether physicians are prescribing antihypertensive drugs appropriately and according to the recommendations of the Canadian Hypertension Society.


METHODS
Retrospective cohort study.


METHODS
Family medicine teaching clinic in Montreal.


METHODS
A cohort of 183 patients followed between 1993 and 1995. Of 350 patients registered at the clinic, 167 were excluded because diagnosis of hypertension was not supported by chart review, their charts contained insufficient information, they were pregnant or younger than 18 years, or they had secondary hypertension and complex medical conditions.


METHODS
The dependent variable was the antihypertensive medication. Independent variables were age and sex of patients, duration of hypertension, total number of visits and number of visits for hypertension, number of physicians consulted at the clinic, associated medical conditions, diagnosis of target organ damage, blood pressure readings, and associated medications.


RESULTS
Diuretics were prescribed most frequently (45.9%). Angiotensin-converting enzyme (ACE) inhibitors ranked second (28.4%), followed by calcium channel blockers (26.2%) and beta-blockers (18.0%). Age, sex, duration of hypertension, and blood pressure readings were not associated with medications. Prescription of beta-blockers was strongly associated with previous myocardial infarction, but not with diagnosis of angina pectoris. Patients with contraindications to beta-blockers were less likely to receive them and more likely to receive calcium channel blockers. Only 32% of diabetic patients received ACE inhibitors.


CONCLUSIONS
Results suggest that some prescriptions for antihypertensive medications are inappropriate, but that physicians are following some of the Canadian Hypertension Society's recommendations. A better understanding of physicians' prescribing behaviours could help target continuing education interventions to improve prescribing for hypertension.
Beaulieu
M D
MD
Family Medicine Clinic, Notre-Dame Hospital. maried.beaulieu@sympatico.ca
Dufresne
L
L
LeBlanc
D
D
D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage / Q000627:therapeutic use; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000787:Angina Pectoris / Q000150:complications; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use; D000959:Antihypertensive Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001794:Blood Pressure; D002121:Calcium Channel Blockers / Q000008:administration & dosage / Q000627:therapeutic use; D002170:Canada; D015331:Cohort Studies; D000075202:Contraindications; D048909:Diabetes Complications; D004232:Diuretics / Q000008:administration & dosage / Q000627:therapeutic use; D011307:Drug Prescriptions; D004502:Education, Medical, Continuing; D005069:Evaluation Studies as Topic; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications; D019338:Polypharmacy; D017410:Practice Guidelines as Topic; D010818:Practice Patterns, Physicians'; D012189:Retrospective Studies; D012737:Sex Factors; D013997:Time Factors
D000319:Adrenergic beta-Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D000959:Antihypertensive Agents; D002121:Calcium Channel Blockers; D004232:Diuretics