For ApoA, when compared with the lowest quarter (0·42 to 1·35 g/L), the highest quarter (1·7 to 2·5 g/L) had a lower risk of dementia (hazard ratio (HR) [95% confidence interval (95% CI)], 0·77 [0·69, 0·86]) (p for trend<0·001) (Figure 1; Supplementary Table 3); when modelled as a continuous measure, the HR [95% CI] per SD was 0·92 [0·88, 0·95]. The gene discussed is APOA1; the disease is dementia.