Adults with diabetes experience a slowdown in several types of mental processing, which appears early in the disease and persists into old age, according to new research. Given the sharp rise in new cases of diabetes, this finding means that more adults may soon be living with mild but lasting deficits in their thought processes.

Researchers at Canada’s University of Alberta analyzed a cross-section of adults with and without adult-onset Type 2 diabetes, all followed in the Victoria Longitudinal Study. At three-year intervals, this study tracks three independent samples of initially healthy older adults to assess biomedical, health, cognitive and neurocognitive aspects of aging. The Neuropsychology study involved 41 adults with diabetes and 424 adults in good health, between ages 53 and 90.

The research confirmed previous reports that diabetes impairs cognition and added two important findings. First, it teased out the specific domains hurt by diabetes. Second, it revealed that the performance gap was not worse in the older group. Thus, the reductions in executive function and processing speed seem to begin earlier in the disease.

Healthy adults performed significantly better than adults with diabetes on two of the five domains tested: executive functioning, with significant differences across four different tests, and speed, with significant differences or trends across five different tests. There were no significant differences on tests of episodic and semantic memory, verbal fluency, reaction time and perceptual speed.

When researchers divided participants into young-old and old-old, with age 70 as the cutoff, they found the same pattern of cognitive differences between young-old and old-old in the diabetes and control groups. Thus, the researchers concluded, the diabetes-linked cognitive deficits appear early and remain stable.

Source: American Psychological Association