3.6 Causal Effects of EBV on CLA
For EBV, we explored the relationship between eight EBV-related
antibodies and CLA. The MR-Egger analysis indicated a potential
reduction in the risk of CLA for the EBV EA-D antibody levels (OR =
0.145, 95% CI = 0.038–0.551, p = 0.016). However, IVW and weighted
median analyses did not find significant associations for any of the
eight antibodies, with p-values exceeding 0.05(Figure. 2).
For the eight EBV-related antibodies, no unbalanced horizontal
pleiotropy was found in any of the instruments (p > 0.05).
Two antibodies (EBV VCA p18 antibody levels and Anti-EBV EA IgG levels)
showed heterogeneity (p = 0.043; p = 0.031), while there was no evidence
of heterogeneity among the remaining six antibodies (Figure. 3h-o).
Furthermore, all funnel plots indicated a slight presence of pleiotropy,
suggesting a potential single instrumental variable affecting the
estimated causal effect (Figure. 4). The leave-one-out analysis showed
that no single SNP strongly influenced the overall effect of exposure on
the outcome (Figure. 5).
In summary, our results suggest a causal relationship between HHV-6 and
CLA, while no such relationships were observed for other herpes viruses.
Sensitivity analyses and tests for pleiotropy and heterogeneity support
the robustness of these findings.