Association of Vitamin D Status of Septic Patients in Intensive Care Units With Altered Procalcitonin Levels and Mortality

Objective: The purpose of this study was to determine whether vitamin D levels correlate with procalcitonin (PCT) levels and mortality in septic patients. Methods: The following data were collected from 236 patients upon admission to intensive care units (ICUs): demographics; Acute Physiology and Chronic Health Evaluation (APACHE) II score; Sequential Organ Failure Assessment (SOFA) score; 25-hydroxyvitamin D (25OHD), PCT, intact PTH, albumin, creatinine, and ionized calcium (iCa) levels; 25OHD sampling seasonality; fluid load (colloid and crystalloid before 25OHD sampling); mechanical ventilation duration; and length of stay (LOS) in the ICU. The primary endpoint was all-cause mortality 28 days after ICU admission. Results: Patients with 25OHD deficiency had significantly higher APACHE II and SOFA scores, positive blood culture rates, PCT levels, intact PTH levels, and 28-day mortality rates. These patients also had lower iCa levels, longer LOS in the ICU, and longer ventilator durations than patients with 25OHD insufficiency or sufficiency. Age, sex, 25OHD sampling seasonality, serum albumin and creatinine levels, and fluid load did not vary among the 3 groups. Serum 25OHD levels at admission were significantly negatively correlated with PCT levels. PTH responders had significantly higher 28-day mortality rates than did PTH nonresponders. Cox regression showed that a 25OHD level of < 20 ng/mL was an independent risk factor for 28-day mortality. Conclusions: Lower serum 25OHD levels at ICU admission were associated with 28-day mortality in septic patients. Serum 25OHD levels were inversely correlated with PCT levels. Hypovitaminosis D was associated with higher mortality rates in PTH responders than in nonresponders.