Improved diabetes control in the elderly delays global cognitive decline.

To examine whether improved diabetes control is related to better cognitive outcomes. Randomized control trial. A randomized trial of telemedicine vs. usual care in elderly persons with type 2 diabetes. Participants were 2169 persons 55 years and older with type 2 diabetes from New York City and Upstate New York. The diabetes case management intervention was implemented by a diabetes nurse, via a telemedicine unit in the participant's home, and in coordination with the primary care physician. Hemoglobin A1c (HbA1c), systolic blood pressure (SBP), and low density lipoprotein cholesterol (LDL), were measured at a baseline visit and at up to 5 annual follow-up visits. Global cognition was measured at those visits with the Comprehensive Assessment and Referral Evaluation (CARE). In mixed models the intervention was related to slower global cognitive decline in the intervention group (p = 0.01). Improvements in HbA1c (p = 0.03), but not SBP or LDL, mediated the effect of the intervention on cognitive decline. Improved diabetes control in the elderly following existing guidelines through a telemedicine intervention was associated with less global cognitive decline. The main mediator of this effect seemed to be improvements in HbA1c.