Duration of obesity raises teens’ diabetes risk
Thursday, 8 September 2011
Being fatter for longer, as well as the degree of overweight, raise a young person’s risk of developing type 2 diabetes in adulthood, especially for younger and Hispanic/black people, shows longitudinal research published online first in Archives of Pediatric and Adolescent Medicine.
US researchers calculated “excess BMI-years” for 8157 people aged 14-21 years, who had been followed for 25 years. An excess BMI-year was a measure of by how much their BMI exceeded 25 (or the 85th percentile for adolescents) as well as how many years they had spent being overweight.
By the age of 40, white men with 200 excess BMI-years had almost triple (2.96 times) the risk of having developed type 2 diabetes as white men with 100 excess BMI-years.
For any given level of excess BMI-years, younger people were more vulnerable to developing diabetes than older groups.
At 0-200 excess BMI years, people in Hispanic and black groups were more at risk of developing diabetes than white people with a similar score. Racial differences in diabetes risk were not apparent at higher levels of 300-500 excess BMI-years.
The authors suggest: “One hypothesis to account for our findings is that a given amount of excess BMI when carried earlier in the life course may be more diabetogenic than the same amount of weight carried later in the life course.”
They add that if further studies confirm their findings “… this would suggest that weight interventions for diabetes prevention may be more effective at younger compared with older ages and that public health programmes may need to prioritise accordingly.”
However, the data on height, weight and diabetes diagnosis used in the study came from self-reported questionnaires, which its authors acknowledge may limit its strength.