Glucose levels and risk of dementia.
Level 3 - non-randomized controlled study
Prospective observational cohort study
PubMed 23924004 · doi:10.1056/NEJMoa1215740
What was done
Researchers evaluated 2,067 dementia-free participants (mean age 76 years; 839 men, 1,228 women; 232 with diabetes, 1,835 without) from the Adult Changes in Thought study. The relationship between dementia risk and 35,264 clinical glucose measurements and 10,208 glycated hemoglobin measurements was analyzed using Cox regression models. Models were stratified by diabetes status and adjusted for age, sex, cohort, education, exercise, blood pressure, smoking, antihypertensive treatment, atrial fibrillation, and coronary and cerebrovascular disease over a median follow-up of 6.8 years.
What was found
A total of 524 participants developed dementia (74 with diabetes, 450 without). Among participants without diabetes, higher average glucose levels over the prior 5 years were associated with higher dementia risk (P=0.01); comparing 115 mg/dL to 100 mg/dL yielded an adjusted hazard ratio (HR) of 1.18 (95% CI, 1.04 to 1.33). Among participants with diabetes, higher glucose levels were also associated with increased dementia risk (P=0.002); comparing 190 mg/dL to 160 mg/dL yielded an adjusted HR of 1.40 (95% CI, 1.12 to 1.76).
Why it matters
This study indicates that elevated blood glucose is associated with increased dementia risk across a continuous spectrum, extending the risk profile to individuals without a diagnosis of diabetes.
Limits
The study is observational, precluding causal inference. The cohort had an advanced baseline age (mean 76 years), limiting generalizability to younger populations, and specific dementia subtypes or mechanisms were not detailed in the abstract.
Cited by
- supports An HbA1c level of 6.0% is associated with an increased risk of dementia and brain shrinkage.