Prior cancer diagnosis and mortality profile in US adults

Introduction

Cancer is the second leading cause of mortality following heart disease in the US. It was estimated that 18.1 million cancer cases were newly diagnosed and 9.6 million people died from cancer globally in 2018.

With the progress in cancer prevention, molecular diagnostics, and cancer treatment, patient survival has been improved and more cancer patients die from non-cancer causes.

Therefore, investigation of detailed mortality profiles of cancer patients is needed to provide better care for cancer patients over the long term.

Some studies have evaluated the main cause of death in people with an individual type of cancer, such as prostate cancer,

breast cancer, and epithelial endometrial cancer. However, only a few studies have investigated the mortality profile overall in cancer patients. Four studies investigated the specific effect of a prior cancer diagnosis on all-cause mortality, ^, or cardiovascular disease (CVD) mortality, or unintentional injury ( i.e. accident) mortality without investigating other types of mortality. Only three studies investigated more detailed mortality in the overall cancer patients from the US, South Korea, and Japan. However, those latter three studies lacked a non-cancer cohort and used age-standardized mortality to report their findings based on the standard population from each country. However, age standardization has limitations. First, it is sensitive to small cell sizes, which can occur, e.g. , when events occur mostly in older age groups, such as CVD mortality. When there are a number of cells with zero events, age standardization could result in an underestimation of the true standard errors.

Second, age standardization does not take into consideration other confounding factors such as lifestyle and clinical confounders which could be different between cancer patients and the general population.

Detailed mortality profiles with multivariate adjustment in participants with a prior cancer diagnosis have not been reported. This study aimed to investigate the mortality profile in participants with a prior cancer diagnosis with adjustment for common risk factors among US adults who attended the National Health and Nutrition Examination Survey (NHANES) from 1988 to 2014.