Major determinants of discontinuation of antihypertensive drug treatment are male sex, young age, mild-to-moderate systolic blood pressure elevation, and birth outside of Sweden.

The efficacy of antihypertensive drug therapy is undisputed, but observational studies show that few patients reach a target blood pressure o140/90 mm Hg. However, there is limited data on the drug prescribing patterns and their effectiveness in real practice. This retrospective observational survey of electronic patient records extracted data from 24 Swedish primary healthcare centres, with a combined registered population of 330 000 subjects. We included all patients X30 years with a recorded diagnosis of hypertension who consulted the centres in 2005 or 2006 (n ¼ 21 167). Main outcome measures were systolic and diastolic blood pressures, and prescribed antihypertensive drug classes. Only 27% had a blood pressure o140/ 90 mm Hg. The number of prescribed drugs increased with age, except among the oldest (X90 years). Only 29% of patients given monotherapy had a blood pressure o140/90 mm Hg. Women more often received diuretics (52 vs 42%), and less often angiotensinconverting enzyme inhibitors (22 vs 33%) and calcium channel blockers (26 vs 31%) than men. b-Blockers and diuretics were the most common drug classes prescribed, independent of comorbidity. In conclusion, one out of four primary care patients with hypertension reach target blood pressure. More frequent use of drug combinations may improve blood pressure control.

This large and representative database shows that there is room for improvement of BP control in Sweden. The SPCCD will provide a rich source for further research of hypertension and its complications.