ACE gene polymorphism and insulin action in older subjects and healthy centenarians.

Abstract

To evaluate the possible relationship between angiotensin-converting enzyme (ACE) insertion-deletion (ID) genotype and insulin resistance in a population of healthy older Italian subjects. Prospective recruitment of a convenience sample. One hundred twenty-five subjects age 62 to 105 in good health and not taking any drug known to interfere with glucose metabolism. In the sample population, the relative frequencies of the ACE genotypes deletion-deletion (DD) (0.424), ID (0.400), and insertion-insertion (II) (0.176) were not significantly different from values predicted by Hardy-Weinberg equilibrium. The genotype distribution was similar in men and women. Subjects carrying the II genotype had a higher FPG (P <.001) and FPI (P <.001) than did subjects with DD or ID genotype. Subjects with II genotype also had a significantly higher HOMA index than did subjects with DD or ID genotype (P for trend <.002). In a multivariate stepwise regression analysis, the ACE ID polymorphism was significantly and independently associated with the HOMA index (P <.001). The same result was confirmed performing multivariate analysis in the younger group and centenarians separately. In an older population, the presence of II ACE genotype is associated with a high degree of insulin resistance independent of other anthropometric variables known to interfere with insulin action; this association is significant in both the younger subjects and the centenarians.