FAMILIAL AGGREGATION OF MEDIAL ARTERIAL CALCIFICATION IN PIMA-INDIANSWITH AND WITHOUT DIABETES

OBJECTIVE - Little is known about medial arterial calcification (MAC) other than its association with age, sex, diabetes, and diabetes compl ications Familial aggregation of this disorder was studied to determin e the importance of potential genetic factors and to assess whether su ch familial aggregation was independent of that of diabetes. RESEARCH DESIGN AND METHODS - Members of 1,256 Pima Indian nuclear families wit h 3,339 offspring were examined radiologically for MAC of the feet. Mu ltiple logistic regression analyses were used to compare the presence of the disorder in a parent with the presence of MAC in an offspring a nd to determine whether familial aggregation of MAC was independent of parental diabetes. RESULTS - Controlled for age, sex, diabetes, serum cholesterol, and blood pressure, offspring of one parent with MAC had 3.3 (95% CI 1.5-7.6) times the odds of MAC as did offspring of parent s without MAC, and offspring with both parents affected had an even hi gher risk (odds ratio, 8.1; 95% CI 3.4-18.8). Controlled for offspring age and sex and for parental age and diabetes, parental MAC was assoc iated with the disorder in offspring (P < 0.001), but the effect of pa rental diabetes on MAC in the offspring was not significant when contr olled for parental MAC (P = 0.36). Furthermore, offspring of nondiabet ic parents with MAC, controlled for age, sex, diabetes, and diabetes d uration, had 1.7 (95% CI 0.9-3.1) times the odds of MAC than did offsp ring of diabetic parents with MAC. CONCLUSIONS - Independent of parent al age and diabetes and offspring age, sex, diabetes, and diabetes com plications, parental MAC confers an increased risk of MAC in offspring . These findings suggest that the factors responsible for the Familial clustering of MAC may be different from those for diabetes.