IGF1 and dementia: The HR of dementia per 1-SD increment of IGF-1 (5.65 nmol/L) was 0.69 (95% CI: 0.62–0.77) in the group below 18 nmol/L, and 1.06 (95% CI: 1.01–1.11) in the group above 18 nmol/L in model 3 (Table 2).