Table 3.
Cox proportional hazards model of body mass index at mid-life and risk of dementia. Figures are hazard ratios (95% confidence intervals)
| Body mass index* | Adjusted for age at mid-life exam and education | Also adjusted for age at diagnosis, race, marital status, sex | Also adjusted for mid-life and late life comorbidity† |
|---|---|---|---|
| All | |||
| Obese | 1.38 (1.10 to 1.72) | 1.56 (1.24 to 1.96) | 1.74 (1.34 to 2.26) |
| Overweight | 1.16 (1.01 to 1.34) | 1.22 (1.04 to 1.42) | 1.35 (1.14 to 1.60) |
| Underweight | 1.41 (0.82 to 2.39) | 1.46 (0.84 to 2.54) | 1.24 (0.70 to 2.21) |
| Women | |||
| Obese | 1.59 (1.21 to 2.08) | 1.80 (1.35 to 2.39) | 2.07 (1.49 to 2.89) |
| Overweight | 1.34 (1.09 to 1.63) | 1.36 (1.10 to 1.68) | 1.55 (1.22 to 1.97) |
| Underweight | 1.63 (0.93 to 2.84) | 1.73 (0.97 to 3.08) | 1.45 (0.79 to 2.67) |
| Men | |||
| Obese | 1.08 (0.74 to 1.58) | 1.22 (0.83 to 1.79) | 1.30 (0.84 to 1.87) |
| Overweight | 1.01 (0.82 to 1.25) | 1.07 (0.86 to 1.33) | 1.16 (0.91 to 1.46) |
| Underweight | 0.55 (0.07 to 3.92) | 0.55 (0.08 to 3.96) | 0.53 (0.07 to 3.82) |
*
Obese (≥30), overweight (25.0-29.9), normal (18.5-24.9), underweight (<18.5); reference group is those with normal body mass index.
†
Mid-life comorbidity includes hypertension, diabetes, and high cholesterol; late life comorbidity includes hypertension, stroke, diabetes, ischaemic heart disease, and hyperlipidaemia.