Familial History of Type 2 Diabetes in Patients from Southern Brazil and its Influence on the Clinical Characteristics

Objective: To investigate the presence of maternal and paternal history of type 2 diabetes mellitus (DM) in relatives of 644 type 2 diabetic patients from Southern Brazil, and also to evaluate its influence on the clinical characteristics of this disease. Patients and Methods: Familial history of type 2 DM was investigated by a questionnaire. The maternal and paternal history was investigated over two generations. Complete data sets on familial history were obtained from 396 patients. Results: In general, 76.6% of the patients reported at least one first-degree affected relative. Besides, 31.6% of the patients reported a maternal history of type 2 DM and 12.6% reported a paternal history. Patients with maternal and/or paternal history presented a lower age at type 2 DM diagnosis when compared to patients without familial history. In addition, patients with only paternal history presented a higher frequency of hypertension than patients with no familial history. Conclusions: This study suggests that there is a significant maternal effect in the transmission of type 2 DM in Southern Brazil, and that most of the clinical characteristics of this disease do not differ between patients with or without familial history of type 2 DM. (Arq Bras Endocrinol Metab 2006;50/5:862-868)