Hypertension in diabetes: trends in clinical control in repeated large-scale national surveys from Sweden

Abstract
Hypertension in diabetes is an important and treatable cardiovascular risk factor. Treatment targets from guidelines cannot always be achieved in everyday clinical practice. It is therefore of great importance to monitor trends in hypertension control in defined populations. Patients with type I diabetes (range 6685-10,100; treated hypertension 21-29%) or with type II diabetes (range 15,935-22,605; treated hypertension 47-56%) were included in four national samples between 1996 and 1999. This screening was part of the procedures for the National Diabetes Register in Sweden, which monitors trends in clinical practice and risk factors for patients with diabetes, recruited both in primary health care and at the hospital level. A favourable trend in mean and median blood pressure levels was noticed during the 4-year study period, based either on data from repeated surveys or on repeated measures in the same individual, both for type I diabetes (mean: -2/-2 mmHg; P < 0.01) and for type II diabetes (mean: -5/-3 mmHg; P < 0.001). Correspondingly, the proportion of hypertensive patients in acceptable control of blood pressure (< or =140/85 mmHg) increased (P < 0.001) both in type I diabetes (52.0-57.9%) and in type II diabetes (22.4-33.3%). It was concluded that hypertension is a widespread cardiovascular risk factor in patients with diabetes, especially systolic hypertension. A trend for a better systolic blood pressure control during the late 1990s in hypertensive patients with type II diabetes in Sweden could translate into substantial (estimated) clinical benefits in cardiovascular and diabetes-related morbidity. The National Diabetes Register makes a quality assessment of the hypertension treatment possible.