Inadequate Exercise as a Risk Factor for Sepsis Mortality

Objective

Test whether inadequate exercise is related to sepsis mortality.

Research Design and Methods

Mortality surveillance of an epidemiological cohort of 155,484 National Walkers'' and Runners'' Health Study participants residing in the United States. Deaths were monitored for an average of 11.6-years using the National Death index through December 31, 2008. Cox proportional hazard analyses were used to compare sepsis mortality (ICD-10 A40-41) to inadequate exercise (<1.07 METh/d run or walked) as measured on their baseline questionnaires. Deaths occurring within one year of the baseline survey were excluded.

Results

Sepsis was the underlying cause in 54 deaths (sepsis_underlying) and a contributing cause in 184 deaths (sepsis_contributing), or 238 total sepsis-related deaths (sepsis_total). Inadequate exercise was associated with 2.24-fold increased risk for sepsis_underlying (95%CI: 1.21 to 4.07-fold, P = 0.01), 2.11-fold increased risk for sepsis_contributing (95%CI: 1.51- to 2.92-fold, P<10⁻⁴), and 2.13-fold increased risk for sepsis_total (95%CI: 1.59- to 2.84-fold, P<10⁻⁶) when adjusted for age, sex, race, and cohort. The risk increase did not differ significantly between runners and walkers, by sex, or by age. Sepsis_total risk was greater in diabetics (P = 10⁻⁵), cancer survivors (P = 0.0001), and heart attack survivors (P = 0.003) and increased with waist circumference (P = 0.0004). The sepsis_total risk associated with inadequate exercise persisted when further adjusted for diabetes, prior cancer, prior heart attack and waist circumference, and when excluding deaths with cancer, or cardiovascular, respiratory, or genitourinary disease as the underlying cause. Inadequate exercise also increased sepsis_total risk in 2163 baseline diabetics (4.78-fold, 95%CI: 2.1- to 13.8-fold, P = 0.0001) when adjusted, which was significantly greater (P = 0.03) than the adjusted risk increase in non-diabetics (1.80-fold, 95%CI: 1.30- to 2.46-fold, P = 0.0006).

Conclusion

Inadequate exercise is a risk factor for sepsis mortality, particular in diabetics.