Influence of a familial history of diabetes on the clinical characteristics of patients with Type 2 diabetes mellitus

SUMMARY Aims To evaluate the roles of maternal and paternal diabetes and diabetes in relatives other than parents on the clinical characteristics in Type 2 diabetes mellitus. Methods A total of 2113 Type 2 diabetic patients were recruited, and those with diabetic mothers, diabetic fathers, diabetic relatives other than parents and no known diabetic relatives, were considered separately. Results The prevalence of diabetes in the mother, father and other relatives was 25.5, 6.5 and 21.2%, respectively. No difference in the clinical characteristics was found in patients with diabetes in the mother or father. Patients with parental diabetes were significantly younger, with higher LDL‐cholesterol, prevalence of retinopathy and lower age at diabetes diagnosis than those without familial diabetes; on multiple logistic regression, only age (P = 0.0003), age at diabetes diagnosis (P = 0.0014) (inverse association), and LDL‐cholesterol (P = 0.030) remained significantly associated with parental diabetes. Patients with diabetic relatives other than parents displayed significantly higher total and LDL‐cholesterol, prevalence of retinopathy and lower age at diabetes diagnosis that those with no known diabetic relatives; on multiple logistic regression, only age at diabetes diagnosis was inversely associated with diabetes in relatives other than parents (P = 0.013). Conclusions The data do not indicate a different influence of maternal and paternal diabetes on the clinical characteristics of Type 2 diabetic patients, while there is evidence that parental diabetes brings to an earlier onset of the disease and higher LDL‐cholesterol values; the presence of diabetes in relatives other than parents constituted a small risk for earlier manifestation of the disease.