Association between Alzheimer's disease and risk of cancer: A retrospective cohort study in Shanghai, China

Introduction We investigated the association between Alzheimer's disease (AD) and the risk of cancer in the Chinese population. Methods In this retrospective cohort study, multivariate Cox proportional hazard regression analysis was used to determine the correlation between AD and the risk of various cancers, as shown by hazard ratios (HRs) with 95% confidence intervals (CIs). Results Of 8097 AD patients, the HR for all subsequent cancers was 0.822 (95% CI, 0.728-0.928; P = .002). Among them, three specific cancers were associated with AD: lung cancer (HR, 0.656; 95% CI, 0.494- 0.871; P = .004), prostate and testicular cancer (HR, 0.414; 95% CI, 0.202-0.847; P = .016), and lymphoma (HR, 2.202; 95% CI, 1.005-4.826; P = .049). Conclusion Patients with AD might have a lower chance of developing several cancers, including lung cancer and prostate and testicular cancer. Meanwhile, a positive association between AD and a higher incident rate of lymphoma was observed.