Analyzing Factors of Colorectal Cancer Screening Practice Among Older Asian Americans: Implications for Community-Based Interventions

Background: Colorectal cancer (CRC) is the second most common cancer and the leading cause of death among Korean Americans (KAs). Despite the significant burden on KAs, their CRC screening rates remain almost half of the national target (70.5%) specified by Healthy People 2020. Literature has shown that CRC screening for KAs is associated with age, health insurance, knowledge of screening, attitudes toward screening, and self-efficacy for screening. However, few studies have explored the associations of CRC screening with physical activity and obesity, although research has stated that obese older people are at higher risk for CRC, yet are less likely than normal weight older people to engage in cancer prevention behaviors, including screening and exercise. Thus, this study aimed to (1) examine factors associated with CRC screening among older KAs and (2) particularly assess the effects of levels of exercise and Body Mass Index (BMI) on CRC screening practice in order to provide implications for community-based interventions designed to increase CRC screening through facilitating physical activities among older underserved people. 

Methods: Purposive Convenience sampling was implemented to recruit KAs ages 50 and older residing communities in a southeast metropolitan area in the U.S. A total of 526 KAs participated in a cross-sectional survey, but only 495 KAs completed the survey as to sociodemographics, CRC screening history (i.e., stool-based blood tests, sigmoidoscopy, and colonoscopy), CRC screening knowledge, attitudes toward CRC screening, CRC screening self-efficacy, and health-related information, including BMI, exercise, and health insurance. Most participants were female (62%), married (84%), and uninsured (57%). Their mean age was 59.5 (SD = 7.65), 42% had not completed college, and 43% had an annual household income below $40,000. Descriptive analysis was conducted to examine participants’ sociodemographic characteristics and CRC screening history.

Results: Descriptive analysis showed that about half of the participants were complied with the CRC screening guidelines: annual stool-based blood test, sigmoidoscopy every five years, and colonoscopy every ten years. The results of multivariate logistic regression analysis revealed that those who had ever had any type of CRC screening tests were more likely than those who had not had any screening to have greater screening knowledge (OR = 1.17; 95% CI = 1.04 – 1.30), have greater perceived screening self-efficacy (OR = 1.42; 95% CI = 1.21 – 1.66), have health insurance (OR = 1.92; 95% CI = 1.09 – 3.38), be older (OR = 1.10; 95% CI = 1.06 – 1.14), and do more exercise per week (OR = 1.75; 95% CI = 1.07 – 2.86), respectively, holding all other variables constant.

Conclusions/Implications: The findings suggest culturally appropriate interventions designed to facilitate physical activities for increasing CRC screening among underserved older people. The findings also imply the interventions should focus on improving knowledge, attitudes, and self-efficacy pertaining to CRC screening among ethnically underrepresented older people. Future studies should conduct randomized controlled trials to explain the causal effect of levels of exercise on uptake of CRC screening. Health equity can be advanced by eliminating health disparities in CRC screening in vulnerable older people.