Ezetimibe combined with standard diet and exercise therapy improves insulin resistance and atherosclerotic markers in patients with metabolic syndrome

Aims/Introduction

Ezetimibe lowers serum lipid levels by inhibiting intestinal absorption of dietary and biliary cholesterol. However, the effect of ezetimibe on insulin resistance remains unclear. The aim of the present study was to examine this issue in patients with metabolic syndrome in local-dwelling Japanese, who were not being treated with lipid-lowering drugs.

Materials and Methods

In 2009, 1,943 participants received a health examination in the Tanushimaru Study, a Japanese cohort of the Seven Countries Study, of whom 490 participants had metabolic syndrome. Among them, 61 participants (41 men and 20 women) were examined in the present study. They were treated with 10 mg of ezetimibe once a day for 24 weeks, combined with standard diet and exercise therapy.

Results

Bodyweight (P < 0.001), body mass index (P < 0.001), systolic blood pressure (P = 0.003), diastolic blood pressure (P < 0.001), triglycerides (P = 0.002), non-high-density lipoprotein cholesterol (P = 0.001), low-density lipoprotein cholesterol (P < 0.001) and homeostasis model assessment of insulin resistance (P = 0.011) significantly decreased after the observational period. There were no statistically significant differences in the effects of ezetimibe between men and women. Univariate analysis showed that the reduction of homeostasis model assessment of insulin resistance was not associated with the improvement of other metabolic components.

Conclusions

Ezetimibe combined with standard diet and exercise therapy improves not only bodyweight and atherogenic lipid profiles, but also insulin resistance, blood pressure and anthropometric factors in metabolic syndrome in local-dwelling Japanese. Interestingly, the improvement of insulin resistance had no correlation with other metabolic components.

Plasma aldosterone levels and development of insulin resistance: prospective study in a general population

Aldosterone plays a role in hypertension, and hypertension is prevalent in patients with insulin resistance. Cross-sectional studies have reported that plasma aldosterone levels are higher in patients with insulin resistance. However, it is not known whether plasma aldosterone levels predict the development of insulin resistance. Subjects of the present study were 1235 local residents (490 men and 745 women) who participated in health screenings in Japan in 1999. Plasma aldosterone levels were measured by radioimmunoassay. We investigated the cross-sectional relationship between plasma aldosterone levels and insulin resistance (homeostasis model assessment index ≥1.73 according to the diagnostic criteria used in Japan) in 1088 nondiabetic participants. At the 10-year follow-up, 141 subjects had died, and 260 subjects refused re-examination. We performed a prospective analysis of 564 subjects to predict incident insulin resistance. We found a significant (P<0.001) cross-sectional relationship between plasma aldosterone and homeostasis model assessment index at baseline. In the prospective analysis, a significantly higher (P<0.05) relative risk (1.71 [95% CI: 1.03-2.84]) was observed in the highest tertile versus lowest tertile of plasma aldosterone for the development of insulin resistance, after adjustment for confounding factors. This 10-year prospective study demonstrated that plasma aldosterone levels predicted the development of insulin resistance in a general population.