Prognostic value of urine dipstick proteinuria on mortality after acute ischemic stroke

Abstract

BACKGROUND AND AIMS: Proteinuria is a marker of kidney disease and a strong risk factor for cardiovascular diseases including stroke. This study was aimed at investigating the prognostic value of proteinuria measured by urine dipstick in patients with acute ischemic stroke.

METHODS: This post-hoc analysis of a prospective cohort study included 3404 consecutive patients who had been admitted for acute ischemic stroke between November 2005 and June 2013. Proteinuria was defined as a trace or more of protein on a urine dipstick test routinely performed at admission. Date and cause of death until December 31, 2013 were collected. We investigated the association of proteinuria with all-cause mortality, cardiovascular mortality (defined as ICD-10 codes I00-I99), and non-cardiovascular mortality.

RESULTS: Proteinuria was present in 12.8% of the 3404 patients. During the mean follow-up period of 3.56 ± 2.22 years, there were 681 cases of all-cause mortality (460 cardiovascular deaths and 221 non-cardiovascular deaths). Multivariate Cox regression analysis showed that the presence of proteinuria was an independent risk factor for all-cause mortality (adjusted hazard ratio [HR] 1.69, 95% confidence interval [CI] 1.40-2.04), cardiovascular mortality (adjusted HR 1.65, 95% CI 1.31-2.08), and non-cardiovascular mortality (adjusted HR 1.59, 95% CI 1.13-2.23). Adding proteinuria to the multivariate Cox models moderately improved the model performance for all-cause mortality (integrated area under curve [95% CI]: from 0.800 [0.784-0.816] to 0.803 [0.788-0.818], p = 0.026).

CONCLUSIONS: Proteinuria, which was detected on a urine dipstick test, was a significant predictor of mortality after acute ischemic stroke.