Modification of the effects of age on clinical outcomes through management of lifestyle-related factors in patients with acute ischemic stroke

This study examined the association between age and clinical outcomes after ischemic stroke, and whether the effect of age on post-stroke outcomes can be modified by various factors.We included 12,171 patients with acute ischemic stroke, who were functionally independent before stroke onset, in a multicenter hospital-based study conducted in Fukuoka, Japan. Patients were categorized into six groups according to age: ≤ 45, 46-55, 56-65, 66-75, 76-85, and > 85 years. Logistic regression analysis was performed to estimate an odds ratio for poor functional outcome (modified Rankin scale score of 3-6 at 3 months) for each age group. Interaction effects of age and various factors were analyzed using a multivariable model.The mean age of the patients was 70.3 ± 12.2 years, and 63.9% were men. Neurological deficits at onset were more severe in the older age groups. The odds ratio of poor functional outcome linearly increased (P for trend <0.001), even after adjusting for potential confounders. Sex, body mass index, hypertension, and diabetes mellitus significantly modified the effect of age on the outcome (P < 0.05). The unfavorable effect of older age was greater in female patients and those with low body weight, whereas the protective effect of younger age was smaller in patients with hypertension or diabetes mellitus.Functional outcome worsened with age in patients with acute ischemic stroke, especially in females and those with low body weight, hypertension, or hyperglycemia.