[Patterns in the prescription of antihypertensive  drugs in Norway, 1975-2010].
BACKGROUND
A complete overview of drugs used for hypertension is not available from official data sources. The aim of this study was to investigate the use of blood pressure medication over the years to identify trends in consumption patterns.


METHODS
Data were collected from the Norwegian drug wholesaler statistics for the years 1975-2010 and from the Norwegian prescription database 2004-2010. Defined daily doses (DDD) per 1000 inhabitants per day, number of users and prevalence by gender and age were analysed.


RESULTS
In the period 1975 to 2010 the use of antihypertensives increased from 55 to 248 DDD/1000 inhabitants/day (Norwegian drug wholesaler statistics). Data from the Norwegian prescription database show that in 2010 there were a total of 754 909 users of antihypertensives, of whom 638 830 had received the diagnosis hypertension. Thiazides and angiotensin II antagonists had the greatest increase in number of users from 2004 to 2010. In all ages up to 73 years, a higher proportion of men were prescribed drugs for hypertension in 2010, whereas in the over-73 s these drugs were most widely used by women.


CONCLUSIONS
The use of antihypertensives is steadily increasing. Angiotensin II antagonists and thiazides are the most commonly used drugs. The authorities'' decision in 2004 that thiazides should be regarded as first-line therapy for hypertension probably contributed to increased use of thiazides.
Avdeling for legemiddelepidemiologi, Nasjonalt folkehelseinstitutt, Norway. hege.salvesen.blix@fhi.no
Hege Salvesen
HS
Blix
Knud
K
Landmark
Randi
R
Selmer
Asmund
A
Reikvam
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use; D000959:Antihypertensive Agents / Q000008:administration & dosage* / Q000627:therapeutic use; D002648:Child; D011307:Drug Prescriptions / Q000706:statistics & numerical data*; D004363:Drug Utilization; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009664:Norway / Q000453:epidemiology; D012042:Registries; D049971:Thiazides / Q000008:administration & dosage / Q000627:therapeutic use
D000806:Angiotensin-Converting Enzyme Inhibitors; D000959:Antihypertensive Agents; D049971:Thiazides