Addition of vitamin D status to prognostic scores improves the prediction of outcome in community-acquired pneumonia.

Background: Vitamin D plays a role in host defense against infection. Vitamin D deficiency is common worldwide. The prognostic value of vitamin D levels in pneumonia is unknown. In this study, we aimed to investigate the impact of vitamin D status on outcome in community-acquired pneumonia (CAP).

Methods: We conducted a prospective cohort study in 272 hospitalized patients with CAP. Levels of 25-hydroxyvitamin D, leukocytes, C-reactive protein, and total cortisol and the Pneumonia Severity Index (PSI) and CURB-65 scores were measured on admission. Major outcome measures were intensive care unit (ICU) admission and 30-day mortality.

Results: One hundred forty-three patients (53%) were vitamin D deficient (<50 nmol/L), 79 patients (29%) were vitamin D insufficient (50-75 nmol/L), and 50 patients (18%) were vitamin D sufficient (>75 nmol/L). Vitamin D deficiency was associated with an increased risk of ICU admission and 30-day mortality. Vitamin D status was an independent predictor of 30-day mortality (area under the curve [AUC] =0.69; 95% confidence interval [CI], .57-.80). Multivariate regression analysis including all predictors for outcome resulted in a final model including vitamin D status and the PSI score, with a significantly higher prognostic accuracy compared with the PSI score alone (AUC=0.83; 95% CI, .71-.94).

Conclusions: Vitamin D deficiency is associated with adverse outcome in CAP. Vitamin D status is an independent predictor of 30-day mortality and adds prognostic value to other biomarkers and prognostic scores, in particular the PSI score.

Clinical Trials Registration: NCT00471640.