Age-dependent effects of gastric cancer screening endoscopy on mortality: a nationwide cohort study

Endoscopic screening for gastric cancer reduces mortality, but the optimal upper age limit and modifying role of comorbidity remain unclear.

This nationwide retrospective cohort study used the Korean National Health Insurance Service database linked to national mortality records. Individuals aged ≥40 years who underwent screening esophagogastroduodenoscopy between 2005 and 2010 were included and propensity score-matched to non-screened controls. The primary outcome was gastric cancer-specific mortality. Comorbidity was assessed using the Charlson Comorbidity Index (CCI). Hazard ratios (HRs) were estimated in the matched cohort.

Among 555 904 propensity score-matched individuals (277 952 per group), gastric cancer-specific mortality HRs showed an age-dependent gradient: <1.0 at 50-59 years (HR 0.56, 95%CI 0.34-0.92), 60-64 (0.65, 0.40-1.07), and 65-69 (0.82, 0.58-1.17); close to 1.0 at 70-74 (0.99, 0.75-1.30) and 75-79 (0.92, 0.68-1.24); and elevated at ≥80 years (2.21, 1.49-3.27). Comorbidity further modified this association: HRs were <1.0 in individuals with CCI <3 (0.86, 0.74-1.01) but elevated in those with CCI ≥3 (1.88, 1.42-2.49). In age-CCI analyses, point estimates favored screening across age groups up to age 75-79 years among individuals with CCI 0, but HRs exceeded 1.0 in most age groups with CCI ≥3. Post-endoscopy respiratory or cerebrocardiovascular events increased with age and comorbidity.

The mortality benefit of gastric cancer screening endoscopy diminished with advancing age and comorbidity burden, becoming questionable beyond age 70. At age ≥80 or in individuals with substantial comorbidity, potential harms may outweigh benefits.