Researchers analyzed data from 18,571 adults aged 50 and older across five national aging studies. They tracked how blood sugar levels changed over time and how these changes affected physical function and frailty. The group followed participants for a median of 13.6 years to see how their health evolved.
The study found that having prediabetes at the start was linked to a higher risk of developing functional deficits and frailty compared to having normal blood sugar. Even when blood sugar levels improved and returned to normal range, the risk of these functional issues remained higher than in those who started with normal levels. Diabetes showed the strongest effects on these outcomes.
The researchers used advanced statistical models to account for changes over time. While the study looked at many different measures of health, some specific changes in risk rates did not reach statistical significance. This large, long-term look suggests that prediabetes in older adults reflects a state of metabolic vulnerability connected to the aging process, rather than just a step toward diabetes.