Trajectory of functional decline before and after ischemic stroke: the Northern Manhattan Study

Abstract

Background and purpose: Previous research in our cohort showed a delayed decline in functional status after first ischemic stroke. We compared the long-term trajectory of functional status before and after ischemic stroke.

Methods: The Northern Manhattan Study contains a prospective, population-based study of stroke-free individuals age ≥40 years, followed for a median of 11 years. The Barthel index (BI), a commonly used measure of activities of daily living, was assessed annually. Generalized estimating equations were used to assess functional decline over time before stroke and beginning 6 months after stroke. Follow-up was censored at the time of recurrent stroke.

Results: Among 3298 participants, 210 participants had an ischemic stroke during follow-up and had poststroke BI assessed. Mean age (±SD) was 77±9 years, 38% were men, 52% were Hispanic, 37% had diabetes, and 31% had coronary artery disease. There was no difference in rate of functional decline over time before and after stroke (P=0.51), with a decline of 0.96 BI points per year before stroke (P<0.0001) and 1.24 BI points after stroke (P=0.001). However, when stratified by insurance status, among those with Medicaid or no insurance, in a fully adjusted model, there was a difference in slope before and after stroke (P=0.04), with a decline of 0.58 BI points per year before stroke (P=0.02) and 1.94 BI points after stroke (P=0.001).

Conclusions: In this large, prospective, population-based study with long-term follow-up, there was a significantly steeper decline in functional status after ischemic stroke compared with before stroke among those with Medicaid or no insurance, after adjusting for confounders.

Figure. Conceptual depiction of the course of functional status before and after stroke among those with Medicaid or no insurance