Diabetes and ischaemic stroke outcome

Aim To compare all-cause mortality, stroke recurrence and functional outcomes in people who have experienced stroke, with and without diabetes. Methods We captured data on population-based ischaemic strokes (2006-2012) in Nueces County, Texas. Data were collected from participant interviews and medical records. Differences in cumulative mortality and stroke recurrence risk by diabetes status were estimated at 30 days and 1 year using Cox models. Differences in 90-day functional outcomes (activities of daily living/instrumental activities of daily living score: range 1-4; higher scores worse) by diabetes status were assessed using Tobit regression. Effect modification by ethnicity was examined. Results There were 1301 ischaemic strokes, 46% with history of known diabetes. The median (interquartile range) age was 70 (58-81) years and 61% were Mexican American. People with diabetes were younger and more likely to be Mexican American compared with those without diabetes. After adjustment, diabetes predicted mortality (30-day hazard ratio 1.44, 95% CI 0.97-2.12; 1-year hazard ratio 1.47, 95% CI 1.09-1.97) but not stroke recurrence (1-year hazard ratio 1.27, 95% CI 0.78-2.07). People with diabetes had a worse functional outcome score that was explained by cardiovascular risk factors and pre-stroke factors. Diabetes was not associated with functional outcome in the fully adjusted model (final adjusted activities of daily living/instrumental activities of daily living score difference 0.11, 95% CI -0.07 to 0.30). Effect modification by ethnicity was not significant (P>0.3 for all models). Conclusions Diabetes was associated with higher mortality and worse functional outcome but not stroke recurrence. Interventions are needed to decrease the adverse outcomes associated with diabetes, particularly in Mexican-American people.