Aldosterone status associated with insulin resistance in patients with heart failure - Data from the ALOFT study

Background: Aldosterone has a key role in the pathophysiology of heart failure. In around 50% of such patients, aldosterone "escapes" from inhibition by drugs that interrupt the renin-angiotensin axis; such patients have a worse clinical outcome. Insulin resistance is a risk factor in heart failure and cardiovascular disease. The relation between aldosterone status and insulin sensitivity was investigated in a cohort of heart failure patients. Methods: 302 patients with New York Heart Association (NYHA) class II-IV heart failure on conventional therapy were randomised in the ALiskiren Observation of heart Failure Treatment study (ALOFT), designed to test the safety of a directly acting renin inhibitor. Plasma aldosterone and 24-hour urinary aldosterone excretion, as well as fasting insulin and homeostasis model assessment of insulin resistance (HOMA-IR) were measured. Subjects with aldosterone escape and high urinary aldosterone were identified according to previously accepted definitions. Results: 20% of subjects demonstrated aldosterone escape and 34% had high urinary aldosterone levels. At baseline, there was a positive correlation between fasting insulin and plasma (r = 0.22 p