MTHFR and ischemic stroke: Only in individuals with the MTHFR 677CC genotype but not CT/TT genotype was folate adversely correlated with stroke (HR: 0.88, 95% CI: 0.79–0.97, p for interaction = 0.026) and ischemic stroke (HR: 0.88, 95% CI: 0.80–0.98, p for interaction = 0.035).