AIMS: Statins are the main lipid-lowering treatment in both primary and 
secondary prevention populations. Whether statins deteriorates glycemic control, 
predisposing to the onset of diabetes mellitus has been a matter of recent 
concern. Statins may accelerate progression to diabetes via molecular mechanisms 
that impact insulin sensitivity and secretion. In this review, we debate the 
relative effect of statins in driving insulin resistance and the impairment of 
insulin secretion.
METHODS: Narrative overview of the literature synthesizing the findings of 
literature was retrieved from searches of computerized databases, hand searches, 
and authoritative texts employing the key words "Statins", "Randomized Clinical 
Trial", "Insulin sensitivity", "Insulin resistance", "Insulin Secretion", 
"Diabetes Mellitus" alone and/or in combination.
RESULTS: The weight of clinical evidence suggests a worsening effect of statins 
on insulin resistance and secretion, anyway basic science studies did not find a 
clear molecular explanation, providing conflicting evidence regarding both the 
beneficial and the adverse effects of statin therapy on insulin sensitivity.
CONCLUSIONS: Although most of the clinical studies suggest a worsening of 
insulin resistance and secretion, the cardiovascular benefits of statin therapy 
outweigh the risk of developing insulin resistance, thus the data suggest the 
need to treat dyslipidemia and to make patients aware of the possible risk of 
developing type 2 diabetes or, if they already are diabetic, of worsening their 
metabolic control.