Data do not support claimed benefit of combination over single treatment

EDITOR—Mogensen et al interpret their results as showing that the combination of lisinopril plus candesartan was more effective than either agent alone at lowering blood pressure and reducing the urinary albumin:creatinine ratio over 24 weeks in patients with type 2 (non-insulin dependent) diabetes.1 They state, “our results … support this new and potentially highly beneficial therapeutic approach for the prevention of diabetic renal and vascular disease.”

The authors' interpretation of the renoprotective effect of the combination and its superiority in lowering blood pressure does not seem to be supported by the results. Several methodological issues in particular limit their interpretation.

Firstly, the authors state in the abstract that “the reduction in urinary albumin:creatinine ratio with combination treatment … was greater than with either candesartan … or lisinopril.” Table 4, however, shows that the difference …