Metabolic syndrome and smoking may justify earlier colorectal cancer screening in men.
BACKGROUND
Gender, smoking, and metabolic syndrome (MetS) are important risk factors of colorectal neoplasm. Whether presence of these factors may warrant earlier screening remains unclear.


OBJECTIVE
To compare age- and gender-specific risk of colorectal neoplasms in association with smoking and MetS under endoscopic or stool-based screening.


METHODS
Cross-sectional observational study.


METHODS
Screening center in a university hospital in Taiwan.


METHODS
A cohort of 10,884 average-risk individuals who received concurrent screening colonoscopy and fecal immunochemical testing (FIT).


METHODS
First, the prevalence of colorectal neoplasms and positive predictive value of FIT relative to age, gender, smoking, and MetS. Second, the number of colonoscopies needed to detect 1 advanced neoplasm with different strategies.


RESULTS
Male smokers aged 40 to 49 years had a significantly higher prevalence of advanced neoplasms and positive predictive value of stool tests than nonsmoking counterparts. The prevalence of advanced neoplasms in concurrent MetS and smoking (6.2%) or smoking alone (3.8%) men aged 40 to 49 years was higher than that of average-risk women aged 50 to 59 years (2.1%) (P = .03 and .04, respectively). The number of colonoscopies needed to detect 1 advanced neoplasm in men aged 40 to 49 years with concurrent MetS and smoking, smoking, MetS, and women aged 50 to 59 years was, respectively, 14.6, 24.8, 39.8, and 47.4 in the colonoscopy scenario and 1.7, 4.6, 5.7, and 8.3 in the FIT scenario.


CONCLUSIONS
Self-selective bias may exist for subjects voluntarily submitted to health check-ups.


CONCLUSIONS
MetS and smoking significantly impact both the prevalence of colorectal neoplasms and the diagnostic yields of screening tests in men aged 40 to 49 years. Whether our findings justify earlier screening in this subgroup requires further study.
Department of Internal Medicine, National Taiwan University Hospital, Bei-Hu branch, Taipei, Taiwan; Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan.
Li-Chun
LC
Chang
Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan; Health Management Center, National Taiwan University Hospital, Taipei, Taiwan.
Ming-Shiang
MS
Wu
Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan; Health Management Center, National Taiwan University Hospital, Taipei, Taiwan.
Chia-Hung
CH
Tu
Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan; Health Management Center, National Taiwan University Hospital, Taipei, Taiwan.
Yi-Chia
YC
Lee
Department of Pathology, National Taiwan University Hospital, Taipei, Taiwan.
Chia-Tung
CT
Shun
Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan; Health Management Center, National Taiwan University Hospital, Taipei, Taiwan.
Han-Mo
HM
Chiu
D000328:Adult; D014408:Biomarkers, Tumor / Q000032:analysis; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D003430:Cross-Sectional Studies; D005243:Feces / Q000737:chemistry; D005260:Female; D006801:Humans; D008297:Male; D008403:Mass Screening; D024821:Metabolic Syndrome / Q000150:complications* / Q000453:epidemiology; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects*; D013624:Taiwan / Q000453:epidemiology
D014408:Biomarkers, Tumor