INTRODUCTION. The renin–angiotensin–aldosterone system plays a key role in the pathogenesis of arterial hypertension and its complications. Many clinical trials have proven also its role in the development of diabetes and control of glycemia. A double or even triple blockade of that system may besides the hemodynamic effect induce various metabolic alterations. The aim of the study was to assess the influence of the combined therapy with the angiotensin-converting enzyme inhibitor and aldosterone antagonist on insulin sensitivity and serum leptin concentration in patients with type 2 diabetes on a long-term angiotensin-converting enzyme inhibitor therapy.
MATERIAL AND METHODS. Twenty five patients were included. At baseline and after two 6-week long periods in which in a random order either spironolactone (25 mg/day) or placebo were given, serum levels of insulin, glucose, leptin, C-reactive protein, insulin sensitivity index (HOMA-S) and 24-hour blood pressure were assessed.
RESULTS. Six weeks of spironolactone therapy induced a statistically significant increase of serum leptin concentration. The same was not observed after placebo administration. Serum C-reactive protein decreased after spironolactone as well as blood pressure during the early morning activity. The mean 24-hour blood pressure was not changed as well as serum levels of glucose and insulin, HOMA-S and body mass.
CONCLUSIONS. The combined treatment with an angiotensin-converting enzyme inhibitor and low-dose spironolactone compared to the treatment with the angiotensin-converting enzyme inhibitor alone may significantly decrease inflammation and afferent regulation of apetite but do not influence insulin resistance. Those effects do not seem to be related to the change of 24-hour blood pressure.