Prediabetes is not associated with cognitive impairment after stroke, whereas a diagnosis of type 2 diabetes (T2D) increases the risk for poorer cognitive function at 3 to 6 months after stroke, according to study results published in Stroke.
Diabetes has been associated with cognitive impairment in patients who have had a stroke, but the effect of prediabetes is not clear. The goal of the current study was to explore the association between T2D and impaired fasting glucose (IFG) during hospitalization for acute stroke and poststroke cognitive impairment.
The researchers used data from the STROKOG (Stroke and Cognition) consortium and collected information on 1601 patients with stroke (mean age, 66.0 years; 63% men) from 7 international cohorts in Australia, France, Korea, the Netherlands, Singapore, and the United States.
According to their medical history and fasting plasma glucose during the hospital stay, patients were classified to 1 of 3 groups: T2D (fasting plasma glucose ≥7 mmol/L or prior T2D diagnosis or treatment), IFG (fasting plasma glucose between 6.1 and 6.9 mmol/L), and normal fasting plasma glucose (<6.1 mmol/L). Almost all patients (99%) had an ischemic stroke and 36% overall had T2D, 12% had IFG, and 52% were found to have normal glucose homeostasis.
Individuals with T2D had significantly poorer cognitive function in global cognition and in all domains compared with patients with normal fasting plasma glucose (global cognition z scores in T2D vs normal group: SD, -0.59; 95% CI, -0.82 to -0.36; P <.001). For patients with T2D, the greatest relative deficits in cognition were in the attention domain, followed by the perceptual motor and executive function domains.
There were no significant differences in global cognition between individuals with IFG and those with normal fasting plasma glucose (global cognition z scores in IFG vs normal group: SD, -0.10; 95% CI, -0.45 to 0.24; P =.55).
The study had several limitations, including the cross-sectional design, an inability to assess the effect of the duration and severity of diabetes on cognitive function, and possible unknown confounders.
Taken together, the researchers concluded that their findings emphasize “…the importance of interventions to prevent the progression of prediabetes to diabetes mellitus in stroke patients, as well as the evaluation of diabetes mellitus self-care skills in diabetic patients and the simplification of those routines whenever possible.”
Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Lo JW, Crawford JD, Samaras K, et al. Association of prediabetes and type 2 diabetes with cognitive function after stroke: a STROKOG collaboration study [published online May 14, 2020]. Stroke. doi:10.1161/STROKEAHA.119.028428