Abstract

OBJECTIVE. At birth, the lifetime risk of developing diabetes is 1 in 3, but lifetime risks across body mass index (BMI) categories are unknown. We estimated BMI-specific lifetime diabetes risk for the U.S. and age-, sex-, ethnicity-specific subgroups.

RESEARCH DESIGN & METHODS. National Health Interview Survey data (n=780,694, 1997-2004) were used to estimate age-, race-, sex-,and BMI-specific prevalence and incidence of diabetes in 2004. U.S. Census Bureau age-, race-, and sex-specific population and mortality rate estimates for 2004 were combined with two previous studies of mortality to estimate Diabetes-BMI-specific mortality rates. These estimates were used in a Markov model to project lifetime risk of diagnosed diabetes by baseline age, race, sex, and BMI.

RESULTS. Lifetime diabetes risks (percent) at age 18 increased from 7.6, to 70.3 between underweight and very obese men, and from 12.2, to 74.4 for women. The lifetime risk difference was lower at older ages. At age 65, compared with normal-weight males, lifetime risk differences (percent) increased from +3.7 to +23.9 percentage points, between overweight and very obese men, and from +8.7 to 26.7 percentage points for women. BMI's impact on diabetes duration also decreased with age.

CONCLUSIONS. Overweight, and especially obesity, particularly at younger ages, substantially increases lifetime risk of diagnosed diabetes, while their impact on diabetes risk, life expectancy, and diabetes duration diminishes with age.