Table 1

Associations of environmental risk score and its joint effects with genetic risk on gastric cancer

No. of cases (person-years)HR (95% CI)aP
Environmental risk scoreb
Per SD increase621 (17,329)1.13 (1.04–1.22)0.0023
 Low ERS482 (13,840)Ref
 High ERS139 (3,489)1.29 (1.06–1.55)0.0092
Grouped by genetic risk
 Low genetic risk
  Low ERS74 (2,932)Ref
  High ERS15 (671)0.79 (0.45–1.38)0.41
 Medium genetic risk
  Low ERS297 (8,113)1.68 (1.30–2.18)8.39 × 10−5
  High ERS90 (2,206)2.20 (1.60–3.01)8.86 × 10−7
 High genetic risk
  Low ERS111 (2,795)2.04 (1.51–2.76)3.37 × 10−6
  High ERS34 (612)4.63 (3.07–6.98)2.90 × 10−13
  P-intc0.042

  • ↵aHRs were estimated using Cox proportional hazards models adjusted for age and gender, and 10 principal components (for joint analyses only).

  • ↵bThe environmental risk score (ERS) was constructed based on 10 environmental lifestyle and dietary risk factors. Individuals in the top 20% of the distribution were classified as having high ERS, while the remainder were defined as low ERS.

  • ↵cP-interaction value (P-int) of genetic risk group and ERS was calculated using the likelihood ratio tests comparing models with and without the interaction term.

  • CI, confidence interval; HR, hazard ratio.