Differences Between Blacks and Whites in the Epidemiology of Insulin-Dependent Diabetes Mellitus in Allegheny County, Pennsylvania

Abstract

Racial differences in the incidence and natural history of insulin-dependent diabetes mellitus were evaluated in Allegheny County, Pennsylvania. The yearly incidence rate for whites was approximately 1.5 times that for blacks. The cumulative risk of developing insulin-dependent diabetes prior to age 20 was greater for whites (3.1/1,000, males; 2.8/1,000, females) than for blacks (1.7/1,000, males; 2.0/1,000, females). There was a slight excess risk for white males versus white females (relative risk = 1.09, p = 0.04), while no sex differential in risk was noted for blacks. The temporal trends and seasonal patterns were similar. Blacks more frequently possessed human lymphocyte antigen (HLA)-DR3/X and whites DR4/X; however, the risks associated with these antigens were similar by race. At onset, blacks had evidence of greater immunologic disturbance and less frequently reported infection than whites, although blacks more often had evidence of previous coxsackie viral infections. Evaluation of mortality patterns by race revealed that blacks had a higher mortality rate than whites. By 20 years duration of diabetes, blacks had a 2.4-fold increase in the risk of mortality compared with whites.

Racial Differences in Metabolic Control of Children and Adolescents With Type I Diabetes Mellitus

“…At any rate, this finding is supportive of recent epidemiological research indicating increased incidence of type I diabetes mellitus among black females relative to black males (22,23).…”

Microvascular Complications of NIDDM in Hispanics and Non-Hispanic Whites: San Luis Valley Diabetes Study

“…Because subjects who were examined were survivors, and if Hispanic mortality from NIDDM differs from the mortality of non-Hispanic whites, there could be different patterns of complications in all Hispanic diabetic subjects that went undetected. We are not aware of case-fatality data for Hispanics with diabetes, however, among younger blacks with IDDM, excess mortality has been reported when compared with whites (33). In our study subjects, physician visits (5.8/person/yr for Hispanics and 4.9/ person/yr for non-Hispanic whites, P = 0.09) and hospitalization frequency (1.7 and 1.5% for Hispanics and non-Hispanic whites, respectively, P = 0.48) did not differ significantly by ethnicity, suggesting that differential medical care access is not a problem.…”

A Twofold Excess Mortality Among Black Compared With White IDDM Patients in Allegheny County, Pennsylvania

“…The diabetic subjects enrolled into the study were registered within 1 year of diagnosis. More detailed procedures for the selection and follow-up of patients from the Allegheny County registry have been described elsewhere (7).…”