Prior Lifestyle and Survival Outcomes After Intensive Care Unit Admission

Background: Although lifestyle is an important and modifiable risk factor for health-related outcomes, no study has focused on the impact of prior lifestyle habits on mortality among critically ill patients after intensive care unit (ICU) admission. Therefore, we aimed to investigate whether prior lifestyle factors affected short- and long-term survival after ICU admission. Methods: In this population-based cohort study using a nationwide registration database in South Korea, we included all patients who were admitted to the ICU between January 1, 2010 and December 31, 2018 and who had undergone standardized health examinations in the year prior to ICU admission. Three lifestyle factors (smoking status, alcohol consumption, and physical activity) were evaluated prior to ICU admission. Results: In total, 585,383 patients admitted to the ICU between 2010 and 2018 were included in the analysis. Of them, 59,075 (10.1%) and 113,476 (19.4%) patients died within 30 days and 1 year after ICU admission, respectively. Current smoking, mild alcohol consumption, and heavy alcohol consumption were not associated with 30- day mortality after ICU admission. One to 3 days per week of intensive physical activity, 4-5 days and 6-7 days per week of moderate physical activity, and 1-3 days, 4-5 days, and 6-7 days per week of mild physical activity were associated with lower odds of 30-day mortality after ICU admission. Similar results were observed for the analyses of 1-year all-cause mortality after ICU admission. Conclusion: Prior lifestyle factors, such as physical activity, were associated with the improvement of both short- and long-term survival outcomes in South Korea. This association was more evident for mild physical activities, such as walking, than for intensive physical activities.