By clinical record review, this retrospective study aims to compare the mortality of sepsis patients with versus without obstructive sleep apnea, who were diagnosed and treated in Taipei Veterans General Hospital, Taiwan.

This retrospective study aims to compare the mortality of sepsis patients with versus without obstructive sleep apnea (OSA). Patients with a diagnosis of sepsis, who had received a prior polysomnography at Taipei Veterans General Hospital during Jan. 1, 2001 to May 31, 2017 will be enrolled. Obstructive sleep apnea (OSA) is defined by an apnea-hypopnea index at least 5/hr with compatible symptoms. Their clinical record will be reviewed and data including demography, polysomnography and details related to sepsis (source of infection, number of organ dysfunction at initial diagnosis of sepsis and survival time) will be collected. The start of the survival time (follow-up time) is the date when sepsis is diagnosed. The end of the survival time (follow-up time) is the date of death or end of hospitalization (date of discharge). Survival analyses will be performed.

Inclusion Criteria:

1. Patients who received received a polysomnography at Taipei Veterans General Hospital during Jan. 1, 2001 to May 31, 2017
2. Patients who were admitted with a diagnosis of sepsis after the polysomnography
3. The diagnosis of sepsis fulfilling the clinical criteria

Exclusion Criteria:

1. Younger than 20 years
2. Not compatible with a definition of sepsis
3. subjects with incomplete data

Sepsis Patients who had received a polysomnography at Taipei Veterans General Hospital during Jan. 1, 2001 to May 31, 2017 will be enrolled.