Relationship between admission serum C-reactive protein and short term outcome following acute ischaemic stroke at a tertiary health institution in Nigeria

Abstract

Background: There is evidence of an association between mediators of inflammation, particularly C-reactive protein (CRP), and outcome of acute ischaemic stroke. This provides a potential opportunity for interventions aimed at improving outcome. There is sparse data exploring the role of inflammatory markers such as CRP and stroke outcome in Africans. The study objective was to determine the association between admission serum CRP levels and short-term outcome in the Nigerian patient presenting with acute ischaemic stroke.
Materials and Methods: Consecutive patients hospitalized for first-ever acute ischaemic stroke at the Lagos University Teaching Hospital, Lagos, Nigeria, were prospectively enrolled between October 2007 and June 2008. Stroke severity was assessed using the National Institutes of Health Stroke Scale (NIHSS). Serum CRP was determined on samples obtained within 7 days of stroke onset. All stroke patients were followed up till day 30 post-stroke. Outcome measures were 30 day Glasgow outcome scale score and functional impairment on the modified Rankin Scale (mRS). An age- and gender-matched healthy control group had serum CRP determined at inclusion. Elevated CRP was defined as any level above the cutoff (mean +2 x standard deviation of CRP level of controls).
Results: Eighty patients with acute ischaemic stroke (47 men and 33 women) and 40 controls (27 male and 13 female) (P = 0.47) were studied. Mean age in cases was 59.1 ± 15.0 years. Mean CRP was significantly higher in stroke cases than controls (17.7 ± 14.4 mg/L versus 1.1 ± 1.7 mg/L respectively) (P < 0.00001). The frequency of elevated CRP (>4.5 mg/L) was 76.3% in stroke (N = 61) and 5% (N = 2) in controls (P < 0.0001). The case fatality rate in stroke with elevated CRP (32.8%) was significantly higher than stroke with normal admission CRP (0%; P= 0.015). The association of higher admission CRP with fatality () was statistically significant (P < 0.0001). Amongst survivors, mean CRP levels were markedly higher in the patients with unfavorable motor outcome (moderate/severe disability; n = 22; 21.5 ± 11.1) compared to those with favorable outcome (mild disability; n = 38; 6.5 ± 6.2) (P < 0.00001). In multivariate regression analysis, only high NIHSS score (P = 0.004) and admission CRP (P = 0.008) were independently associated with case fatality.
Conclusions: Elevated admission CRP and high NIHSS score are independent predictors of short-term case fatality and adverse functional outcome following acute ischaemic stroke in Nigerians.

Key words: C-reactive protein, ischaemic stroke, outcome