Lifestyle factors and risk of multimorbidity of cancer and cardiometabolic diseases: a multinational cohort study

TLDR

Lifestyle factors have been linked to individual non‑communicable diseases, but their role in the development of subsequent multimorbidity of cancer and cardiometabolic diseases has rarely been examined. This study examined how five lifestyle factors relate to the incidence of multimorbidity involving cancer and cardiometabolic diseases. In a prospective cohort of 291,778 adults from seven European countries, multi‑state Cox models and cumulative incidence functions assessed the impact of BMI, smoking, alcohol, physical activity, Mediterranean diet, and a healthy lifestyle index on the risk of developing cancer, CVD, T2D, and subsequent multimorbidity over a median 11‑year follow‑up. The analysis showed that a higher healthy lifestyle index was strongly inversely associated with multimorbidity (HRs per 3‑unit increase 0.75, 0.84, 0.82 for cancer, CVD, T2D), with 10‑year absolute risks of 40%/25% for men/women with unhealthy lifestyles versus 30%/18% for those with healthy lifestyles, indicating that pre‑diagnostic healthy behaviors markedly reduce the risk of cancer, cardiometabolic disease, and multimorbidity.

Abstract

BACKGROUND: Although lifestyle factors have been studied in relation to individual non-communicable diseases (NCDs), their association with development of a subsequent NCD, defined as multimorbidity, has been scarcely investigated. The aim of this study was to investigate associations between five lifestyle factors and incident multimorbidity of cancer and cardiometabolic diseases. METHODS: In this prospective cohort study, 291,778 participants (64% women) from seven European countries, mostly aged 43 to 58 years and free of cancer, cardiovascular disease (CVD), and type 2 diabetes (T2D) at recruitment, were included. Incident multimorbidity of cancer and cardiometabolic diseases was defined as developing subsequently two diseases including first cancer at any site, CVD, and T2D in an individual. Multi-state modelling based on Cox regression was used to compute hazard ratios (HR) and 95% confidence intervals (95% CI) of developing cancer, CVD, or T2D, and subsequent transitions to multimorbidity, in relation to body mass index (BMI), smoking status, alcohol intake, physical activity, adherence to the Mediterranean diet, and their combination as a healthy lifestyle index (HLI) score. Cumulative incidence functions (CIFs) were estimated to compute 10-year absolute risks for transitions from healthy to cancer at any site, CVD (both fatal and non-fatal), or T2D, and to subsequent multimorbidity after each of the three NCDs. RESULTS: During a median follow-up of 11 years, 1910 men and 1334 women developed multimorbidity of cancer and cardiometabolic diseases. A higher HLI, reflecting healthy lifestyles, was strongly inversely associated with multimorbidity, with hazard ratios per 3-unit increment of 0.75 (95% CI, 0.71 to 0.81), 0.84 (0.79 to 0.90), and 0.82 (0.77 to 0.88) after cancer, CVD, and T2D, respectively. After T2D, the 10-year absolute risks of multimorbidity were 40% and 25% for men and women, respectively, with unhealthy lifestyle, and 30% and 18% for men and women with healthy lifestyles. CONCLUSION: Pre-diagnostic healthy lifestyle behaviours were strongly inversely associated with the risk of cancer and cardiometabolic diseases, and with the prognosis of these diseases by reducing risk of multimorbidity.