Stroke-associated pneumonia and acute stroke: frequency, prognostic value and impact of comorbidities

Abstract

The aim of research was to evaluate the frequency of nosocomial pneumonia and other hospital-acquired complications after acute ischemic stroke, to assess the impact of somatic comorbidity on pneumonia occurrence, and to determine the relation of pneumonia to 28-day stroke case fatality. Methods. We performed a prospective study among 207 patients hospitalized for acute ischemic stroke. Stroke severity was evaluated with National Institutes of Health Stroke Scale. Somatic comorbidity was analyzed and graded with Modified Charlson Comorbidity Index. Post-stroke complications were diagnosed using standardized criteria. Results. Mean score of the admission stroke severity in all patients was 12.3±0.4. Of all strokes, 87.4% developed against a background3 2 of preexisting somatic pathology. Low comorbidity was recorded in 101 patients (48.8%), moderate in 58 (28.0%), high in 48 (23.2%); mean Charlson index score was 1.8±0.07 During admission, one or more medical complications occurred in 61 patients (29.5%). The frequency of pneumonia was 19.3% (40 cases): 27.8% in patients with fatal stroke vs. 8.7% in stroke survivors (ð<0.01). The highest was the frequency of pneumonia in patients with high comorbidity (37.5%) compared to those with low (11.9%) or moderate index scores (17.2%). The further analysis showed positive correlation between the increase of Charlson comorbidity index and pneumonia occurrence (r =0,389). Nosocomial pneumonia was related to 28 days case fatality in ischemic stroke (ф=0,241) and this complication significantly increased the probability of death in acute period -OR=3.94 (95% CI 1.59-9.76). Conclusions. Nosocomial pneumonia is a life-threatening complication that affects almost every 5th patient with acute ischemic stroke. The occurrence of stroke-associated pneumonia positively correlates with the higher level of preexisting somatic comorbidity. Development of pneumonia after acute ischemic stroke is an adverse prognostic factor, which increases the probability of 28-days case fatality by 3.9-fold.