C-Reactive Protein and Nitric Oxide Levels in Ischemic Stroke and Its Subtypes: Correlation with Clinical Outcome

K. Rajeshwar, Subhash Kaul, Amal Al-Hazzani, M. Sai Babu, N. Balakrishna, Vandana Sharma, A. Jyothy, Anjana Munshi

Studies in different populations have shown that ischemic stroke can trigger an acute phase response resulting in a rise of plasma concentration of C-reactive protein (CRP). However, there are very limited studies on CRP and first ischemic stroke divided into subtypes. High levels of CRP may also be associated with poor outcome. The present study was taken up to investigate the prognostic value of CRP within 24 h of onset of ischemic stroke. Five hundred and eighty one patients with first stroke and 575 age- and sex-matched healthy controls were involved in the study. High-sensitivity C-reactive protein (hsCRP) levels were estimated, and follow-up interviews were conducted with patients at 3, 6, and 12 months post-event to determine stroke outcome. In addition to this plasma, NO( x ) (nitrate and nitrite) was measured to detect the serum NO (an important biomarker of inflammation and oxidative stress) levels in ischemic stroke patients and controls. The relationship between CRP value and poor outcome (>2 on modified Rankin Scale Score and <5 on an extended Glasgow outcome scale) was studied. There was a significant association between elevated levels of CRP and NO with the disease. A stepwise multiple logistic regression analysis confirmed these findings after adjustment for potential confounders [adjusted odds ratio = 2.890, 95% CI (1.603-5.011) with p < 0.01 and adjusted odds ratio = 2.364, 95% CI (1.312-3.998) with p < 0.01 for hsCRP and NO, respectively]. After adjustment of potential confounders, patients with high CRP levels had a significant increased risk of poor outcome [adjusted odds ratio = 3.50, 95% CI (1.312-6.365) and p < 0.001]. Elevated levels of hsCRP associated significantly with all stroke subtypes classified according to Trial of ORG 10172 in Acute Stroke Treatment classification except for lacunar stroke and stroke of other determined etiology. In conclusion, hsCRP and NO levels predict the incidence of ischemic stroke and hsCRP is an independent prognostic factor of poor outcome at 3 months.