GSTM1 and nosocomial infection: They included the Charlson comorbidity index, Hb, NRS-2002, stroke, admission category, central venous catheter, indwelling urinary catheter, surgery, enteral tube feeding, Barthel Index, Morse Fall Scale, other nosocomial infections, use of sedatives, use of NSAIDs, use of inhaled steroids, use of anticoagulant, and "time at risk".