Relationships of sarcopenia symptoms and dietary patterns with lung cancer risk: a prospective cohort study

Background: Few studies focused on the effects of sarcopenia on lung cancer in the general population and optimizing nutritional intake may be a feasible way to manage sarcopenia. We sought to systematically investigate the associations of sarcopenia symptoms with lung cancer incidence and mortality in the general population, and whether dietary patterns could modify these risks. Methods: A total of 361 763 participants (mean age: 56.2 years; and men: 46.7%) were included in this prospective UK Biobank study. Sarcopenia symptoms (low handgrip strength, low muscle mass and slow walking pace) were determined according to European Working Group of Sarcopenia in Older People 2 (EWGSOP2) criteria. Individuals without any of the three sarcopenia symptoms were classified as the normal control group. Based on the baseline data from food frequency questionnaires, primary dietary patterns were identified through principal component analysis. Cox proportional hazards models were used to examine associations between sarcopenia symptoms as well as dietary patterns and lung cancer. Then we explored the joint effects of sarcopenia symptoms and dietary patterns on lung cancer risk. Results: A total of 3532 incident lung cancer cases and 2073 deaths were documented during a median follow-up of 12 years. All the sarcopenia symptoms were associated with a higher risk of lung cancer incidence than the normal control group, especially in people aged <60 (P_interaction < 0.05). Particularly, a stronger association was observed for slow walking pace with incidence (hazard ratio [HR]: 1.49, 95% confidence interval [CI]: 1.34-1.65) and mortality (HR: 1.54, 95% CI: 1.35-1.75) of lung cancer. Higher adherence to the wholegrain pattern was associated with a greater reduction in the risk of lung cancer incidence (HR_Q4: 0.71, 95% CI: 0.65-0.79) and mortality (HR_Q4: 0.68, 95% CI: 0.60-0.77). The joint analysis demonstrated that the risk of lung cancer-related outcomes associated with low handgrip strength gradually reduced as the quartile of wholegrain pattern scores increased (P_trend < 0.05). Conclusions: Our study indicated that individuals with sarcopenia symptoms suffered a higher risk of lung cancer incidence and mortality even in younger age. A diet abundant in whole grains may help to improve sarcopenia symptoms and reduce adverse lung cancer-related outcomes associated with low handgrip strength.