The effect of discontinuation of antihypertensives on the risk of acute myocardial infarction and stroke.
OBJECTIVE
Adherence to antihypertensive drug treatment is suboptimal. The present study investigates the effect of early treatment discontinuation with antihypertensive drugs on the risk of acute myocardial infarction (AMI) or stroke in daily clinical practice.


METHODS
In the PHARMO Record Linkage System, which includes all records of drug dispensings and hospitalisations for > or = 2 million subjects in the Netherlands, new users of antihypertensive (AHT) drugs > or = 18 years of age were studied during the period 1 January 1993 - 1 October 2002 to determine the risk of AMI or stroke related to persistence with AHT. Patients were initially followed for 2 years to determine persistence with AHT, and then for a further 2 years or until the first hospital admission for AMI or stroke, death, or end of the study period. Patients using AHT for secondary prevention of cardiovascular disease were excluded from the study cohort.


RESULTS
The study cohort included 77 193 AHT users. The percentage of non-persistent patients was 55% at 2 years, with the lowest non-persistence rates for angiotensin-receptor blockers (ARBs) and ACE-inhibitors (40%) and the highest rates for beta-blockers, calcium-channel blockers (CCBs) and diuretics (54-61%). Non-persistent AHT use was associated with a 15% increased risk of AMI (RR 1.15; 95% CI 1.00-1.33) and a 28% increased risk of stroke (RR 1.28; 95% CI 1.15-1.45).


CONCLUSIONS
The results of this study show that in daily clinical practice early discontinuation of antihypertensive drug treatment in primary prevention increases the risk of subsequent AMI or stroke.
Breekveldt-Postma
Nancy S
NS
PHARMO Institute, Utrecht, The Netherlands.
Penning-van Beest
Fernie J A
FJ
Siiskonen
Satu J
SJ
Falvey
Heather
H
Vincze
Gábor
G
Klungel
Olaf H
OH
Herings
Ron M C
RM
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000209:etiology* / Q000517:prevention & control; D010349:Patient Compliance / Q000706:statistics & numerical data; D012307:Risk Factors; D020521:Stroke / Q000209:etiology* / Q000517:prevention & control; D016896:Treatment Outcome; D028761:Withholding Treatment
D000959:Antihypertensive Agents