Table 2 Relative risk of incident hypertension for the highest compared with the lowest category of calcium intake
n | RR (95%CI) | I2(%), Pheterogeneitya | P between b | ||
|---|---|---|---|---|---|
All studies | 8 | 0.89 (0.86–0.93) | 0%, 0.53 | – | |
Source of intake | |||||
Dietary calcium | 7 | 0.89 (0.86–0.93) | 0%, 0.43 | 0.70 | |
Total calcium (diet + supplement) | 1 | 0.85 (0.63–1.07) | – | ||
Dietary source of calcium | |||||
Dairy calcium | 2 | 0.87 (0.83–0.92) | 0%, 0.54 | – | |
Nondairy calcium | 2 | 0.92 (0.72–1.11) | 78.8%, 0.03 | ||
Sex | |||||
Men | 1 | 0.85 (0.76–1.10) | – | 0.38 | |
Women | 2 | 0.87 (0.81–0.92) | 0%, 0.70 | ||
Both | 5 | 0.92 (0.87–0.97) | 0.9%, 0.40 | ||
Geographical region | |||||
US | 4 | 0.89 (0.84–0.93) | 0%, 0.50 | 0.17 | |
Europe | 3 | 1.00 (0.88–1.12) | 0%, 0.90 | ||
Asia | 1 | 0.87 (0.80–0.94) | – | ||
Dietary assessment method | |||||
FFQ | 6 | 0.88 (0.84–0.92) | 0%, 0.85 | 0.06 | |
Dietary record | 1 | 1.01 (0.88–1.14) | – | ||
Median intake | |||||
<700 mg/day | 2 | 0.86 (0.80–0.93) | 0%, 0.71 | – | |
≥700 mg/day | 4 | 0.92 (0.85–0.98) | 36%, 0.19 | ||
Follow-up duration | |||||
<5 years | 5 | 0.92 (0.84–1.00) | 0%, 0.47 | 0.47 | |
≥5 years | 3 | 0.89 (0.85–0.93) | 1%, 0.36 | ||
Number of cases | |||||
<3000 | 5 | 0.95 (0.88–1.02) | 0%, 0.78 | 0.04 | |
>3000 | 3 | 0.87 (0.82–0.92) | 0%, 0.92 | ||
Adjustment for confounders | |||||
Alcohol consumption | Yes | 7 | 0.89 (0.86–0.93) | 1%, 0.42 | 0.88 |
No | 1 | 0.92 (0.63–1.36) | – | ||
Physical activity | Yes | 5 | 0.89 (0.84–0.93) | 2%, 0.39 | 0.48 |
No | 3 | 0.91 (0.84–0.99) | 0%, 0.62 | ||
Smoking | Yes | 4 | 0.89 (0.84–0.94) | 26%, 0.25 | 0.69 |
No | 4 | 0.91 (0.84–0.99) | 0%, 0.68 | ||
Sodium intake | Yes | 3 | 0.87 (0.82–0.91) | 0%, 0.98 | 0.09 |
No | 5 | 0.94 (0.87–1.00) | 0%, 0.54 | ||
Magnesium intake | Yes | 3 | 0.86 (0.80–0.92) | 0%, 0.92 | 0.24 |
No | 5 | 0.91 (0.86–0.97) | 12%, 0.34 | ||
Potassium intake | Yes | 3 | 0.86 (0.80–0.92) | 0%, 0.92 | 0.24 |
No | 5 | 0.91 (0.86–0.97) | 12%, 0.34 |
