Critical illness is associated with decreased plasma levels of coenzyme Q10: a cross-sectional study.

PURPOSE: Plasma coenzyme Q10 (CoQ10) levels are lower in patients with septic shock (SS) than in healthy controls (HCs). However, CoQ10 status in critically ill patients without SS is unknown. Here, we investigated CoQ10 concentrations in patients with SS and without SS as compared with HCs. MATERIALS AND METHODS: We enrolled 36 critically ill patients and 18 HCs. Plasma CoQ10 concentrations were measured, and patients' clinical and demographical data were collected. RESULTS: Plasma CoQ10 concentrations were lower in critically ill patients (0.50±0.36 μg/mL, P<.001), both in patients with SS (0.37±0.25 μg/mL, P=.002) and patients without SS (0.56±0.39, P=.04), as compared with HCs (0.79±0.19). Coenzyme Q10 levels did not differ between patients with SS and patients without SS (P=.13). In critically ill patients, CoQ10 levels inversely correlated with age (r=-0.40, P=.015) and did not correlate with partial pressure of oxygen in the arterial blood/fraction of inspired oxygen, Simplified Acute Physiology Score II, Systemic Organ Failure Assessment score, or mortality. Lower CoQ10 levels were associated with lower activities of daily living score after discharge (P=.005), independent of age. CONCLUSIONS: Decreased plasma CoQ10 levels are not specific to patients with SS, but rather observed in a broad range of critically ill patients. In critically ill patients, CoQ10 insufficiency may be associated with various conditions; age may be a risk factor.