Effect of the angiotensin receptor blocker irbesartan on metabolic parameters in clinical practice: the DO-IT prospective observational study

Aims: A number of intervention studies have shown that therapy with
angiotensin receptor blockers, such as irbesartan, can improve
metabolic parameters and reduce the incidence of diabetes mellitus.
It is unknown whether this observation also holds true in routine
clinical settings. Methods: We evaluated the effect of irbesartan
(150 mg or 300 mg/d) together with or without hydrochlorothiazide
(12.5 mg/d) in 3259 German patients. A total of 750 primary care
physicians evaluated up to 5 subsequent patients with metabolic
syndrome (58.9% diabetic), in whom irbesartan therapy was newly
initiated (87%) or continued (13%). Results: Six months of
irbesartan therapy decreased systolic blood pressure by 14% (157.4
+/- 14.7 vs. 135.0 +/- 10.7 mmHg) and diastolic blood pressure by
13% (92.9 +/- 9.2 vs. 80.8 +/- 6.8 mmHg). This was associated with
a decrease in body weight (-2.3%), fasting glucose (-9.5%), HbA1c
(-4.6%), LDL-cholesterol (-11%), triglycerides (-16%) and gamma-GT
(-12%) and an increase in HDL-cholesterol (+5%). These changes were
somewhat more pronounced in male than in female patients and in
obese than in lean patients. Changes in glucose concentration and
HbA1c were much more prominent in diabetic patients. Conclusion:
Irbesartan therapy improves metabolic parameters in routine
clinical settings. Thus, our study confirms previously published
results from large intervention trials and extends the findings to
routine clinical practice.