# Cumulative Burden of Lifestyle Risk Factors on Cancer in Older Korean Men: A Nationwide Retrospective Cohort Study

## TL;DR

This study shows that unhealthy habits like smoking and drinking over 8 years increase cancer risk in older Korean men.

## Contribution

The study reveals the cumulative and combined long-term effects of lifestyle factors on cancer risk in older Korean men.

## Key findings

- Higher lifestyle risk scores were linked to increased cancer risk over 8 years.
- Men with scores of 9–12 had a 72% higher cancer risk compared to those with scores of 0–2.
- The study emphasizes the importance of maintaining healthy lifestyles to prevent cancer in older men.

## Abstract

Unhealthy lifestyles are known to increase the risk of cancer. This study investigated the long-term cumulative and combined effects of three major unhealthy lifestyle behaviors (smoking, drinking, and lack of regular physical activity) on cancer among older Korean men, after considering the high incidence of cancer and the dominance of correctable, unhealthy lifestyle behaviors among older men within South Korea. Overall, the risk of cancer increased along with increasing lifestyle risk scores reflecting unhealthy behaviors over an 8-year period. These findings highlight the importance of practicing and maintaining healthy lifestyles to prevent cancer in older Korean men.

Background/Objectives: Cancer prevalence is increasing globally due to aging populations. Certain lifestyles are associated with cancer; however, the long-term combined effects of lifestyle factors on cancer has not been investigated. This study aimed to investigate the cumulative effect of lifestyle risk factors over 8 years on cancer in older Korean men. Methods: We assessed 64,756 men aged ≥65 years at the baseline year (2008–2009) using data from the National Health Insurance Service-Senior Cohort. Lifestyle factors, including smoking status, alcohol consumption, and physical activity, were evaluated over four consecutive phases (2002–2003, 2004–2005, 2006–2007, and 2008–2009) of health check-ups, and each participant’s overall lifestyle risk score was calculated after considering the value of a single poor lifestyle factor in each phase as 1, with a cumulative score ranging between 0 and 12. According to the lifestyle risk scores, the hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox proportional hazard regression analysis. Results: Of the 64,756 men, 13,130 cases of cancer developed. The risk of cancer increased as the number of poor lifestyle factors and lifestyle risk score increased from the baseline year during the four phases. Compared to a score of 0–2, the HRs for cancer were 1.10 (0.98–1.23), 1.54 (1.37–1.73), and 1.72 (1.48–1.99) for scores of 3–5, 6–8, and 9–12, respectively. Conclusions: The risk of cancer increased as the cumulative burden of poor lifestyle habits over 8 years increased. Therefore, practicing and maintaining healthy lifestyles is crucial to preventing cancer in older Korean men.