Ten-year trends in non-surgical patients requiring intensive care: Long-term prognostic differences by year of admission.

Background: The aim of the present study is to elucidate prognostic impact of temporal trends of non-surgical patients requiring intensive care over a 10-year period.

Methods And Results: A total of 4276 non-surgical patients requiring intensive care from 2012 to 2021 were enrolled. Patients' backgrounds, in-hospital management, and prognoses were compared between five groups [2012-2013 (n = 825), 2014-2015 (n = 784), 2016-2017 (n = 864), 2018-2019 (n = 939), and 2020-2021 (n = 867)]. During the study period, mean age significantly increased from 69 years in 2012-2013 to 72 years in 2020-2021. Mean Acute Physiology and Chronic Health Evaluation scores significantly increased from 10 points in 2012-2013 to 12 points in 2020-2021. The median duration of intensive care unit stays increased from 3 to 4 days. Kaplan-Meier survival curve analysis showed that survival rates during 30- and 365-days were significantly lower in 2020-2021 than in 2012-2013, but it was not significantly different by a Cox proportional hazards regression model in 30 days. A Cox proportional hazards regression model revealed that the risks of 365-day all-cause death were significantly higher in patients enrolled in 2016-2017 (HR: 1.324, 95 % CI: 1.042-1.680, p = 0.021), in 2018-2019 (HR: 1.329, 95 % CI: 1.044-1.691, p = 0.021), and in 2020-2021 (HR: 1.409, 95 % CI: 1.115-1.779, p = 0.004).

Conclusion: The condition of patients requiring intensive care is becoming more critical year by year, leading to poorer long-term prognoses despite improvements in treatment strategies. These findings emphasize the importance of additional care management after admission into non-surgical intensive care units, particularly for the aging society of Japan.