The presence of hypothermia within 24 hours of sepsis diagnosis predicts persistent lymphopenia.

OBJECTIVE

To determine whether hypothermia within 24 hours of sepsis diagnosis is associated with development of persistent lymphopenia, a feature of sepsis-induced immunosuppression.

DESIGN

Retrospective cohort study.

SETTING

A 1,200-bed university-affiliated tertiary care hospital.

PATIENTS

Adult patients diagnosed with bacteremia and sepsis within 5 days of hospital admission between January 1, 2010, and July 31, 2012.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Leukocyte counts were recorded during the first 4 days following sepsis diagnosis. Persistent lymphopenia was defined as an absolute lymphocyte count less than 1.2 cells/μL×10(3) present on the fourth day after diagnosis. Of the 445 patients with sepsis included, hypothermia developed in 64 patients (14.4%) (defined as a body temperature<36.0°C) within 24 hours of sepsis diagnosis. Hypothermia was a significant independent predictor of persistent lymphopenia (adjusted odds ratio, 2.70 [95% CI, 1.10, 6.60]; p=0.03) after accounting for age, disease severity, comorbidities, source of bacteremia, and type of organism. Compared with the nonhypothermic patients, hypothermic patients had higher 28-day (50.0% vs 24.9%, p<0.001) and 1-year mortality (60.9% vs 47.0%, p=0.001).

CONCLUSIONS

Hypothermia is associated with higher mortality and an increased risk of persistent lymphopenia in patients with sepsis, and it may be an early clinical predictor of sepsis-induced immunosuppression.