Figure 1.

Restricted cubic splines for the association between serum total homocysteine concentrations and risk of dementia and its subtypes. Solid lines represent the HRs; dashed lines represent the 95% CIs. Knots were placed at the 5th, 35th, 65th and 95th percentiles (5.0, 7.3, 9.5 and 18.2 µmol/L) of serum total homocysteine. A reference point was set at 5.0 µmol/L. Serum total homocysteine values over 20 µmol/L were not present in the plots. The risk estimates were adjusted for age, sex, education, hypertension, diabetes, serum total cholesterol, body mass index, estimated glomerular filtration rate, history of stroke, current smoking, current drinking, regular exercise, serum albumin, serum folate and serum vitamin B₁₂ levels (log-transformed).