Table 2.
Absolute rates and age and multivariable adjusted hazard ratios of all cause and cardiovascular mortality by categories of average cumulative intake of total and dietary calcium
| Variables | Calcium intake (mg/day) | ||||
|---|---|---|---|---|---|
| <600 | 600-999 | 1000-1399 | ≥1400 | ||
| Analyses based on dietary calcium intake | |||||
| Person years at risk | 50 150 | 743 403 | 292 899 | 8428 | |
| All causes: | |||||
| No of deaths | 597 | 8011 | 3208 | 128 | |
| Rate per 1000 person years (95% CI) | 11.9 (11.0 to 12.9) | 10.8 (10.5 to 11.0) | 11.0 (10.6 to 11.3) | 15.2 (12.8 to 18.1) | |
| Age adjusted hazard ratio (95% CI) | 1.60 (1.47 to 1.74) | 1.00 (reference) | 0.93 (0.90 to 0.97) | 1.35 (1.13 to 1.60) | |
| Adjusted hazard ratio* (95% CI) | 1.38 (1.27 to 1.51) | 1.00 (reference) | 1.00 (0.96 to 1.04) | 1.40 (1.17 to 1.67) | |
| Cardiovascular disease: | |||||
| No of deaths | 219 | 2576 | 1025 | 42 | |
| Rate per 1000 person years (95% CI) | 4.4 (3.8 to 5.0) | 3.5 (3.3 to 3.6) | 3.5 (3.3 to 3.7) | 5.0 (3.7 to 6.7) | |
| Age adjusted hazard ratio (95% CI) | 1.90 (1.65 to 2.18) | 1.00 (reference) | 0.93 (0.87 to 1.00) | 1.37 (1.01 to 1.86) | |
| Adjusted hazard ratio* (95% CI) | 1.63 (1.42 to 1.87) | 1.00 (reference) | 1.01 (0.94 to 1.09) | 1.49 (1.09 to 2.02) | |
| Ischaemic heart disease: | |||||
| No of deaths | 113 | 1274 | 515 | 30 | |
| Rate per 1000 person years (95% CI) | 2.3 (1.9 to 2.7) | 1.7 (1.6 to 1.8) | 1.8 (1.6 to 1.9) | 3.6 (2.5 to 5.1) | |
| Age adjusted hazard ratio (95% CI) | 1.85 (1.53 to 2.25) | 1.00 (reference) | 0.97 (0.87 to 1.07) | 2.01 (1.40 to 2.88) | |
| Adjusted hazard ratio* (95% CI) | 1.65 (1.36 to 2.01) | 1.00 (reference) | 1.03 (0.93 to 1.15) | 2.14 (1.48 to 3.09) | |
| Stroke: | |||||
| No of deaths | 57 | 740 | 297 | 6 | |
| Rate per 1000 person years (95% CI) | 1.1 (0.9 to 1.5) | 1.0 (0.9 to 1.1) | 1.0 (0.9 to 1.1) | 0.7 (0.3 to 1.6) | |
| Age adjusted hazard ratio (95% CI) | 1.77 (1.35 to 2.32) | 1.00 (reference) | 0.94 (0.82 to 1.07) | 0.68 (0.31 to 1.52) | |
| Adjusted hazard ratio* (95% CI) | 1.50 (1.14 to 1.97) | 1.00 (reference) | 1.02 (0.89 to 1.17) | 0.73 (0.33 to 1.65) | |
| Analyses based on total calcium intake | |||||
| Person years at risk | 49 195 | 705 006 | 313 628 | 27 051 | |
| All causes: | |||||
| No of deaths | 586 | 7603 | 3405 | 350 | |
| Rate per 1000 person years (95% CI) | 11.9 (11.0 to 12.9) | 10.8 (10.5 to 11.0) | 10.9 (10.5 to 11.2) | 12.9 (11.7 to 14.4) | |
| Age adjusted hazard ratio (95% CI) | 1.59 (1.46 to 1.73) | 1.00 (reference) | 0.86 (0.82 to 0.89) | 0.72 (0.65 to 0.80) | |
| Adjusted hazard ratio* (95% CI) | 1.40 (1.28 to 1.52) | 1.00 (reference) | 1.03 (0.99 to 1.07) | 1.40 (1.25 to 1.57) | |
| Cardiovascular disease: | |||||
| No of deaths | 217 | 2464 | 1073 | 108 | |
| Rate per 1000 person years (95% CI) | 4.4 (3.9 to 5.0) | 3.5 (3.4 to 3.6) | 3.4 (3.2 to 3.6) | 4.0 (3.3 to 4.8) | |
| Age adjusted hazard ratio (95% CI) | 1.89 (1.65 to 2.18) | 1.00 (reference) | 0.83 (0.78 to 0.90) | 0.67 (0.55 to 0.81) | |
| Adjusted hazard ratio* (95% CI) | 1.65 (1.43 to 1.90) | 1.00 (reference) | 1.04 (0.96 to 1.12) | 1.51 (1.23 to 1.84) | |
| Ischaemic heart disease: | |||||
| No of deaths | 111 | 1225 | 533 | 63 | |
| Rate per 1000 person years (95% CI) | 2.3 (1.9 to 2.7) | 1.7 (1.6 to 1.8) | 1.7 (1.6 to 1.9) | 2.3 (1.8 to 3.0) | |
| Age adjusted hazard ratio (95% CI) | 1.82 (1.50 to 2.22) | 1.00 (reference) | 0.86 (0.78 to 0.95) | 0.83 (0.65 to 1.08) | |
| Adjusted hazard ratio* (95% CI) | 1.65 (1.35 to 2.01) | 1.00 (reference) | 1.05 (0.94 to 1.16) | 1.90 (1.45 to 2.49) | |
| Stroke: | |||||
| No of deaths | 57 | 709 | 313 | 21 | |
| Rate per 1000 person years (95% CI) | 1.2 (0.9 to 1.5) | 1.0 (0.9 to 1.1) | 1.0 (0.9 to 1.1) | 0.8 (0.5 to 1.2) | |
| Age adjusted hazard ratio (95% CI) | 1.78 (1.36 to 2.34) | 1.00 (reference) | 0.84 (0.73 to 0.96) | 0.44 (0.29 to 0.68) | |
| Adjusted hazard ratio* (95% CI) | 1.53 (1.17 to 2.01) | 1.00 (reference) | 1.04 (0.90 to 1.19) | 0.96 (0.61 to 1.50) | |
Calcium intake by categories refers to cumulative average intake in cohort.
*Adjusted for age, total energy and vitamin D intake, a healthy dietary pattern, body mass index, height, living alone, educational level, physical activity level, smoking status, use of calcium containing supplements, and Charlson’s comorbidity index.