Influence of social isolation and loneliness on the prognosis of advanced lung cancer patients: a prospective cohort study

Purpose The purpose of this study was to investigate the impact of social isolation and loneliness on the overall survival and death at home in patients with lung cancer. Methods This prospective cohort study was conducted in a Japanese tertiary hospital. The enrollment period was from April 2018 to March 2020. Patients with pathologically diagnosed advanced lung cancer were included in this study. The primary outcome was overall survival, whereas the secondary outcome was death at home. The exposures were social isolation and loneliness. Results A total of 211 patients were enrolled and divided into two groups and further into quartiles according to their social isolation and loneliness level, respectively. The hazard ratios of social isolation were 1.65 (95% confidence interval; 1.12 to 2.44) and 1.87 (95% confidence interval; 1.15 to 3.03) in the univariate analysis, while 1.40 (95% confidence interval; 0.92 to 2.13) in the multivariate analysis with complete case and multiple imputation. The odds ratio of death at home with social isolation was 3.47 (95% confidence interval; 1.08 to 11.1) in the multivariate analysis with multiple imputation. Loneliness was not associated with overall survival or death at home. Conclusions Our study suggests that social isolation may be related to overall survival and death at home among patients with advanced lung cancer. More attention should be given to such patients at the time of diagnosis.