The Effect of Irbesartan in Reducing Cardiovascular Risk in Hypertensive Type 2 Diabetic Patients: an Observational Study in 16,600 Patients in Primary Care

Objectives: As arterial hypertension substantially increases the risk of premature death, cardiovascular disease and renal insufficiency in patients with type 2 diabetes, effective and safe antihypertensive therapy is of importance. Therefore, the effect of irbesartan as monotherapy, or in fixed combination with hydrochlorothiazide, on blood pressure, metabolic parameters and microalbuminuria and the safety and tolerability of the drug were assessed.

Research Design And Methods: Multicentric, prospective, open phase IV study over 3 months in 16,600 patients with the clinical diagnoses of hypertension and type 2 diabetes. Blood pressure was measured sphygmometrically and albuminuria was assessed with semi-quantitative urine dipsticks.

Main Outcome Measures: Systolic (SBP) and diastolic (DBP) blood pressure reduction, proportion of patients with microalbuminuria and cardiovascular risk calculated based on the SCORE score, each after a follow-up of 3 months compared to baseline. Number and nature of adverse events (AEs).

Results: The sample consisted of 51.3% men, mean age was 62.2+/-10.7 years, 53.9% of patients were overweight and 26.4% were obese. Mean SBP/DBP decrease after 3 months was 22.3/11.2 mmHg. The BP lowering effect was similar in the analyses of various subgroups (according to age group, sex, presence of micro- or macrovascular complications). Irbesartan treatment reduced the percentage of patients with microalbuminuria from 45.6% to 30.6% at 3 months (32.9% relative reduction). Metabolic parameters (lipids, blood glucose, HbA1c) and weight were improved significantly or showed trends for improvement, respectively. The mean 10-year cardiovascular risk as calculated with the SCORE score was decreased from a baseline value of 9.8% to 5.7% (-58% relative reduction). Tolerability was excellent: only 0.3% experienced an AE.

Conclusions: Treatment with irbesartan in patients with concomitant hypertension and type 2 diabetes led to large blood pressure reductions. In view of the renoprotective effect documented by the reduced rate of patients with albuminuria, and the improvement of further metabolic parameters, these changes translate into a reduction of cardiovascular risk.