Predictors of successful long-term blood pressure control in type 2 diabetic patients: data from the Swedish National Diabetes Register (NDR)

Hypertension in patients with diabetes is a well recognized cardiovascular risk factor for which the benefits of treatment are strongly evidence based. Less is known about predictors for successful long-term blood pressure control in these patients, including the potential role of body mass index (BMI), glycaemic control, microalbuminuria and smoking.We used longitudinal data on risk factor levels from repeated clinical surveys of 1759 type 2 diabetic patients in the Swedish National Diabetes Register (NDR), a nationwide annual registration of quality indicators in diabetes care. Subjects with successful blood pressure (BP) control (systolic BP135 mmHg and diastolic BP85 mmHg) at baseline in 1997, in 2001, and at follow-up in 2003, were compared to subjects with BP controlor= 135/85 mmHg.Logistic regression analysis disclosed that successful BP control during the study period was predicted by lower BMI (P0.001), a lower frequency of microalbuminuria (P = 0.002), and lower age (P0.001) at baseline in 1997, and was still associated with lower BMI (P0.001), a lower frequency of microalbuminuria (P = 0.01) and lower age (P0.001) at follow-up. Successful BP control was also associated at follow-up with a lower frequency of the metabolic syndrome (30 versus 75%) and lower predicted 10-year risks [United Kingdom Prospective Diabetes Study (UKPDS) Risk Engine] of coronary heart disease (14 versus 29%) and stroke (10 versus 22%) (all P0.001).A lower BMI and absence of microalbuminuria were strong independent predictors of long-term successful BP control in type 2 diabetic patients, also characterized by a lower frequency of the metabolic syndrome and lower 10-year risk of cardiovascular disease. This implies the long-term benefits on BP control of lifestyle measures as well as control of microalbuminuria.