Research Article

Joint Effect of CFH and ARMS2/HTRA1 Polymorphisms on Neovascular Age-Related Macular Degeneration in Chinese Population

Table 4

Measures from the departure-from-additivity model for the joint effect of CFH rs1061170 and HTRA1 rs3793917 with nAMD.

MeasuresEstimateLower 95% CIUpper 95% CI

The synergy index ()A2.631.096.38
AP (%)B55.70%21.40%89.90%
RERIC5.44−1.7112.59

The synergy index () was estimated by the formula (RR11 − 1)/((RR10 − 1) + (RR01 − 1)).
BAP, the attributable proportion due to interaction, was calculated using RERI/RR11.
CThe relative excess risk due to interaction (RERI) was calculated by RR11 − RR10 − RR01 + 1.
RR11, RR10, and RR01 were relative risk exposed to both two factors, only the first factor, and only the second factor, respectively.