Impaired Glucose Tolerance and Risk for Mild Cognitive Impairment and Dementia:Results from the SPRINT‐MIND Trial

Background In epidemiological studies, persons with a diagnosis of diabetes mellitus (DM), especially those with coexisting hypertension, have been shown to be at increased risk for dementia.[1‐3] However, the relationship between impaired glucose tolerance (IGT) and future risk of Mild Cognitive Impairment (MCI) and dementia is less clear, especially in persons without diagnosed DM . The SPRINT‐MIND trial (4) provides an opportunity to assess the relationship between baseline glucose level and risk for transition to mild cognitive impairment in the context of hypertension control. Method Randomized clinical trial (n = 9,361) conducted at 102 sites in the United States and Puerto Rico among adults aged 50 years or older with hypertension but without diagnosed diabetes or history of stroke. Baseline serum glucose obtained fasting and incidence of adjudicated MCI and probable dementia (PD) was calculated. Results were also stratified by age, baseline cardiovascular disease risk, and baseline systolic blood pressure. Result At baseline, 4398 participants (58%) had a serum glucose < 100 mg/dl and 3606 (42%) had a serum glucose >100. Overall, 389 (7.9%) of participants in the normoglycemic group and 250 (6.9%) of participants in the impaired glucose tolerance group developed MCI. For incident PD, 204 (4.1%) and 118 (3.3%) cases occurred in in persons with normal vs. impaired glucose tolerance. Incidence MCI or Dementia did not significantly differ when the results were stratified by baseline age or blood pressure. Conclusion In persons with hypertension but without diagnosed diabetes, baseline impaired glucose tolerance does not confer elevated risk for MCI or dementia.