Kunping Cui,1,* Yi Mao,2,* Shuang Feng,3 Haixia Luo,2 Jiao Yang,2 Ruyi Xu,1 Lang Bai1 

1Center of Infectious Diseases, West China Hospital of Sichuan University, Chengdu, Sichuan, 610041, People’s Republic of China; 2Intensive Care Unit, Public Health Clinical Center of Chengdu, Chengdu, Sichuan, 610000, People’s Republic of China; 3Ultrasonic Medicine, Public Health Clinical Center of Chengdu, Chengdu, Sichuan, 610000, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Lang Bai, Center of Infectious Diseases, West China Hospital of Sichuan University, Chengdu, Sichuan, 610041, People’s Republic of China, Tel +86-18980602254, Email pangbailang@163.com

Purpose: Age is considered a vital factor in intensive care units (ICUs) because of its association with physiological frailty, comorbidities, and immune system function. Previous studies have examined the association between age and prognosis in patients with tuberculosis (TB) or sepsis; however, the association between age and prognosis in ICU patients with TB complicated by sepsis is rare. This study aimed to assess the association between age and the prognosis of patients in the ICU with TB complicated by sepsis.
Patients and Methods: Data from the ICU of the Public Health Clinical Center of Chengdu were analyzed using the multivariable Cox regression model, stratified analysis with interaction, restricted cubic spline (RCS), and threshold effect analysis to investigate the association between age and 28-day all-cause mortality in patients with TB complicated by sepsis.
Results: In total, 520 patients diagnosed with TB and sepsis were enrolled (120 women [23.1%]; median age, 64 years). The association between age and risk of death exhibited a J-shaped curve on the RCS (P for nonlinearity = 0.001). In the threshold analysis, the hazard ratio for the risk of death was 1.104 (95% confidence interval, 1.05– 1.16) in participants aged ≥ 66.2 years. The risk of death increased by 10.4% with every 1-year increase in age in patients with TB complicated by sepsis. No significant association was found between age and 28-day all-cause mortality in patients aged < 66.2 years.
Conclusion: A nonlinear relationship was observed between age and short-term all-cause mortality in patients in the ICU with TB complicated by sepsis. Patients with a higher age at admission may have a higher risk of death and require focused attention, close monitoring, and early treatment to reduce mortality.

Keywords: sepsis, tuberculosis, age, 28-day all-cause mortality, intensive care unit