Adverse housing conditions are associated with the risk of developing diabetes

Fair or poor housing conditions are associated with the risk of developing diabetes in urban, middle-aged African-Americans according to a study published in the Aug. 15 issue of the American Journal of Epidemiology by a team of investigators from Indiana University School of Medicine, the Regenstrief Institute, Washington University in St. Louis and other institutions.

The researchers studied men and women in their homes (apartment or house) and environs in two St. Louis neighborhoods – one a poor, inner-city area and the other a less impoverished, suburban area that included several pockets of residents from a variety of socioeconomic backgrounds. Adjusting for previously recognized diabetes risk factors such as weight, smoking, exercise, alcohol use, marital status and education, the researchers found that housing conditions influenced the risk of developing diabetes, although there was no direct association with conditions in the neighborhoods immediately outside their homes.

"We found a strong link between housing and diabetes risk but it's not clear exactly how housing conditions are exerting this influence," says study senior author Douglas K. Miller, M.D., Richard M. Fairbanks Professor in Aging Research at IU School of Medicine and a Regenstrief Institute research scientist. "However, it is clear that it won't be possible to reduce disparities in health status among subgroups in the population and thus improve health without understanding how a person's environment can affect that person's health."

"We looked at several factors to see if they could clarify why housing conditions were contributing to the development of diabetes, but none of these factors seemed to explain the relationship at all," explains Mario Schootman, Ph.D., lead author and chief of the Division of Health Behavior Research at Washington University. "However, there were several potential explanations such as environmental contaminants that we were unable to measure, so additional study is clearly indicated."

Quality of housing was evaluated based on cleanliness inside of the building and the physical condition of the building's interior and exterior, as well as the condition of the furnishings in the building. Neighborhoods were rated based on noise, air quality and the conditions of houses, streets, yards and sidewalks. Broken windows, bad siding on homes, cracks in the sidewalks and nearby industrial sites or traffic noise lowered a neighborhood’s rating. Housing and neighborhood conditions were classified as fair, poor, good or excellent.

This study is part of a larger health research project involving African-Americans. In the original project, researchers looked at several factors responsible for the higher incidence of health problems experienced by later middle-aged and older African-Americans living in St. Louis. That larger project gathered data from 998 African-Americans in the St. Louis area who were born between 1936 and 1950. When that project began, diabetes already was very common in this population. More than 25 percent had the disease at the time initial interviews were conducted. The new study found that over the next three years another 10 percent developed diabetes.

"The rate at which this African-American population is developing new onset diabetes is extremely important as well," Dr. Miller notes. "At this rate, and combined with the group who had diabetes at baseline, more than one-half of the population will be diabetic after 10 years. With all the adverse health effects of diabetes, this is a hugely important issue for middle-aged African-Americans. Although we did not have the opportunity to conduct similar research in other cities with large numbers of urban African-Americans such as New York City, Los Angeles and Atlanta, we believe it is likely that the findings would be comparable in those cities as well."

The researchers say that additional studies are needed to determine what specifically increased the risk of diabetes as a result of poor housing conditions, but many factors have already been ruled out. The current study was funded by the National Institutes of Health.