Fig. 1

Stratified analyses. A Association of healthy lifestyle score with mortality among US cancer survivors stratified by mental health. B Association of mental health with mortality among US cancer survivors stratified by healthy lifestyle score. Mental health was assessed using the PHQ-9. Mild and major depression was defined by the cut-off of PHQ-9 score 5–9 and ≥ 10, respectively. The following covariates were adjusted: age at the time of interview, sex, education level, ratio of family income to poverty, race and ethnicity, sleep duration, prevalent diabetes, hypertension, dyslipidemia, history of cardiovascular disease, the number of cancer types, age at the first cancer diagnosis. The multiplicative interaction was evaluated by including a cross-product term of healthy lifestyle score (0–1, 2, 3–5) and mental health (PHQ-9 score 0–4, 5–9, ≥ 10) into the corresponding models. Abbreviations: PHQ-9, Patient Health Questionnaire; HR, hazard ratio; CI, confidence interval