PA change | Dementia (n) | Mortality (n) | Person-years | Mortality rate* | HR (95% CI) | ||
Model 1† | Model 2‡ | Model 3§ | |||||
All-cause dementia | |||||||
Light PA | |||||||
No to No | 33 778 | 9951 | 124 461 | 80.0 | 1 (reference) | 1 (reference) | 1 (reference) |
Yes to No | 10 456 | 2934 | 38 515 | 76.2 | 0.95 (0.92 to 1.00) | 0.92 (0.89 to 0.96) | 0.93 (0.89 to 0.97) |
No to Yes | 9580 | 2183 | 36 742 | 59.4 | 0.74 (0.71 to 0.78) | 0.78 (0.75 to 0.82) | 0.79 (0.75 to 0.83) |
Yes to Yes | 6438 | 1363 | 23 975 | 56.9 | 0.71 (0.67 to 0.76) | 0.69 (0.66 to 0.74) | 0.70 (0.67 to 0.75) |
Moderate PA | |||||||
No to No | 52 563 | 14 605 | 194 224 | 75.2 | 1 (reference) | 1 (reference) | 1 (reference) |
Yes to No | 3707 | 984 | 13 869 | 71.0 | 0.94 (0.88 to 1.01) | 0.90 (0.85 to 0.97) | 0.91 (0.86 to 0.98) |
No to Yes | 3128 | 655 | 12 281 | 53.3 | 0.70 (0.65 to 0.76) | 0.78 (0.72 to 0.84) | 0.78 (0.72 to 0.84) |
Yes to Yes | 854 | 187 | 3318 | 56.4 | 0.75 (0.65 to 0.86) | 0.73 (0.63 to 0.85) | 0.74 (0.64 to 0.86) |
Vigorous PA | |||||||
No to No | 50 142 | 14 191 | 184 981 | 76.7 | 1 (reference) | 1 (reference) | 1 (reference) |
Yes to No | 4938 | 1242 | 18 638 | 66.6 | 0.87 (0.82 to 0.92) | 0.89 (0.84 to 0.94) | 0.89 (0.84 to 0.95) |
No to Yes | 3798 | 743 | 14 772 | 50.3 | 0.65 (0.61 to 0.70) | 0.76 (0.70 to 0.82) | 0.76 (0.71 to 0.82) |
Yes to Yes | 1374 | 255 | 5302 | 48.1 | 0.62 (0.55 to 0.71) | 0.69 (0.61 to 0.78) | 0.70 (0.61 to 0.79) |
Alzheimer’s disease | |||||||
Light PA | |||||||
No to No | 24 372 | 7117 | 88 271 | 80.6 | 1 (reference) | 1 (reference) | 1 (reference) |
Yes to No | 7521 | 2098 | 27 185 | 77.2 | 0.96 (0.91 to 1.01) | 0.92 (0.88 to 0.97) | 0.93 (0.88 to 0.97) |
No to Yes | 6681 | 1526 | 25 344 | 60.2 | 0.74 (0.70 to 0.79) | 0.78 (0.74 to 0.82) | 0.78 (0.74 to 0.83) |
Yes to Yes | 4702 | 984 | 17 256 | 57.0 | 0.71 (0.66 to 0.76) | 0.68 (0.63 to 0.73) | 0.69 (0.64 to 0.74) |
Moderate PA | |||||||
No to No | 37 887 | 10 473 | 137 624 | 76.1 | 1 (reference) | 1 (reference) | 1 (reference) |
Yes to No | 2654 | 681 | 9847 | 69.2 | 0.91 (0.84 to 0.98) | 0.86 (0.80 to 0.93) | 0.88 (0.81 to 0.95) |
No to Yes | 2124 | 440 | 8215 | 53.6 | 0.70 (0.64 to 0.77) | 0.75 (0.68 to 0.83) | 0.76 (0.69 to 0.83) |
Yes to Yes | 611 | 131 | 2370 | 55.3 | 0.72 (0.61 to 0.86) | 0.70 (0.59 to 0.83) | 0.71 (0.60 to 0.85) |
Vigorous PA | |||||||
No to No | 36 282 | 10 177 | 131 556 | 77.4 | 1 (reference) | 1 (reference) | 1 (reference) |
Yes to No | 3435 | 858 | 12 880 | 66.6 | 0.86 (0.80 to 0.92) | 0.86 (0.80 to 0.92) | 0.87 (0.81 to 0.93) |
No to Yes | 2603 | 508 | 9992 | 50.8 | 0.65 (0.60 to 0.71) | 0.75 (0.69 to 0.82) | 0.76 (0.69 to 0.83) |
Yes to Yes | 956 | 182 | 3629 | 50.2 | 0.65 (0.56 to 0.75) | 0.69 (0.60 to 0.80) | 0.70 (0.61 to 0.82) |
Vascular dementia | |||||||
Light PA | |||||||
No to No | 4180 | 1175 | 15 538 | 75.6 | 1 (reference) | 1 (reference) | 1 (reference) |
Yes to No | 1295 | 337 | 4813 | 70.0 | 0.93 (0.82 to 1.05) | 0.90 (0.80 to 1.02) | 0.90 (0.80 to 1.02) |
No to Yes | 1300 | 243 | 4962 | 49.0 | 0.65 (0.56 to 0.74) | 0.73 (0.63 to 0.83) | 0.73 (0.64 to 0.84) |
Yes to Yes | 761 | 140 | 2802 | 50.0 | 0.67 (0.56 to 0.79) | 0.69 (0.58 to 0.83) | 0.70 (0.59 to 0.83) |
Moderate PA | |||||||
No to No | 6469 | 1669 | 24 057 | 69.4 | 1 (reference) | 1 (reference) | 1 (reference) |
Yes to No | 526 | 135 | 1964 | 68.8 | 0.99 (0.83 to 1.18) | 0.93 (0.78 to 1.10) | 0.93 (0.78 to 1.11) |
No to Yes | 440 | 70 | 1721 | 40.7 | 0.58 (0.46 to 0.74) | 0.76 (0.60 to 0.96) | 0.76 (0.60 to 0.97) |
Yes to Yes | 101 | 21 | 374 | 56.1 | 0.81 (0.53 to 1.25) | 0.85 (0.55 to 1.31) | 0.84 (0.55 to 1.30) |
Vigorous PA | |||||||
No to No | 6158 | 1624 | 22 934 | 70.8 | 1 (reference) | 1 (reference) | 1 (reference) |
Yes to No | 698 | 161 | 2577 | 62.5 | 0.88 (0.75 to 1.04) | 0.95 (0.80 to 1.11) | 0.95 (0.81 to 1.12) |
No to Yes | 507 | 91 | 1939 | 46.9 | 0.66 (0.54 to 0.82) | 0.84 (0.68 to 1.04) | 0.85 (0.69 to 1.05) |
Yes to Yes | 173 | 19 | 667 | 28.5 | 0.40 (0.26 to 0.63) | 0.47 (0.30 to 0.74) | 0.48 (0.30 to 0.75) |
HRs (95% CIs) were calculated using multivariable Cox proportional hazards regression analysis.
Light PA engagement was defined as performing ≥30 min of light-intensity PA for ≥5 times/week; Moderate PA as performing ≥30 min of moderate-intensity PA for ≥5 times/week; vigorous PA as performing ≥20 min of vigorous-intensity PA for ≥3 times/week.
*Mortality rate per 1000 person-years.
†Model 1 was unadjusted.
‡Model 2 was adjusted for age, sex, residential area, income, smoking status, alcohol consumption, body mass index, hypertension, type 2 diabetes, dyslipidaemia and chronic kidney disease.
§Model 3 was adjusted for age, sex, residential area, income, smoking status, alcohol consumption, body mass index, hypertension, type 2 diabetes, dyslipidaemia, chronic kidney disease, disability and number of anti-dementia medications used.
CI, confidence interval; HR, hazard ratio; PA, physical activity.