Table 1.
Participant demographics for women with and without a history of kidney stones for postmenopausal women in the Women's Health Initiative Observational Study.
| No History of Nephrolithiasis n (%) | History of Nephrolithiasis n (%) | p value | ||
|---|---|---|---|---|
| n= 80,451 (96.1%) | n= 3,471(3.9%) | |||
|
Demographics and History
| ||||
| Age at enrollment (years) | 0.001 | |||
| 50-59 | 25,801 (32.1) | 1,060 (30.5) | ||
| 60-69 | 35,652 (44.3) | 1,536 (44.3) | ||
| ≥70 | 18,998 (23.6) | 875 (25.2) | ||
| Mean±SD | 63.5 ± 7.3 | 63.9 ± 7.3 | 0.005 | |
| Race/ethnicity | <0.001 | |||
| White | 78,584 (85.5) | 2,953 (85.3) | ||
| Black | 5,663 (7.1) | 204 (5.9) | ||
| Hispanic | 2,557 (3.2) | 159 (4.6) | ||
| Other | 3,435 (4.3) | 147 (4.2) | ||
| Baseline history of diabetes mellitus | 3,990 (5.0) | 302 (8.7) | <0.001 | |
| Baseline supplemental calcium use | 20,397 (25.4) | 632 (18.2) | <0.001 | |
| Hormone therapy use | <0.001 | |||
| Never | 31,846 (39.6) | 1,330 (38.4) | ||
| Prior | 11,897 (14.8) | 570 (16.4) | ||
| Current | 36,635 (45.6) | 1,567 (45.2) | ||
| BMI (kg/m2) | <0.001 | |||
| <18.5 Underweight | 938 (1.2) | 40 (1.2) | ||
| 18.5-24.9 Normal weight | 32,228 (40.5) | 1,155 (33.6) | ||
| 25-29.9 Overweight | 27,141 (34.1) | 1,155 (33.6) | ||
| 30-34.9 Moderately obese | 12,208 (15.3) | 624 (18.2) | ||
| ≥35 Severely obese | 7,062 (8.9) | 459 (13.4) | ||
| Mean±SD | 27.1 ± 5.8 | 28.3 ± 6.2 | <0.001 | |
| Geographical Region | 0.02 | |||
| Northeast | 18,601 (23.1) | 735 (21.2) | ||
| South | 20,305 (25.2) | 942 (27.1) | ||
| Midwest | 18,114 (22.5) | 770 (22.2) | ||
| West | 23,431 (29.1) | 1,024 (29.5) | ||
| Stone event during the study | 2,390 (3.0) | 547 (15.8) | <0.001 | |
| Study participation follow-up (years) | ||||
| Mean±SD | 7.2 ± 1.1 | 7.2 ± 1.1 | <0.001 | |
| Median (IQR 25th-75th percentile) | 8 (7-8) | 8 (7-8) | 0.005 | |
|
Dietary Intake | ||||
| Fiber intake (quintile) | Intake range (g/d)* | <0.001 | ||
| Lowest | 0-10.6 | 15,937 (19.8) | 822 (23.7) | |
| Second | 10.6-14.0 | 16,017 (19.9) | 729 (21.0) | |
| Third | 14.0-17.5 | 16,149 (20.1) | 663 (19.1) | |
| Fourth | 17.5-21.9 | 16,156 (20.1) | 627 (18.1) | |
| Highest | 21.9-99.4 | 16,192 (20.1) | 630 (18.2) | |
| Mean±SD | 16.6 ± 7.0 | 16.6 ± 7.0 | 16.0 ± 7.0 | <0.001 |
| Fruit intake (quintile) | (portions/day)* | <0.001 | ||
| Lowest | 0-1.0 | 16,109 (20.0) | 899 (25.9) | |
| Second | 1.0-1.5 | 15,821 (19.7) | 706 (20.3) | |
| Third | 1.5-2.1 | 16,527 (20.5) | 699 (20.1) | |
| Fourth | 2.1-3.0 | 15,868 (19.7) | 568 (16.4) | |
| Highest | 3.0-11 | 16,126 (20.0) | 599 (17.3) | |
| Mean±SD | 2.1 ± 1.3 | 2.1 ± 1.3 | 1.9 ± 1.3 | <0.001 |
| Vegetable intake (quintile) | (portions/day)* | <0.001 | ||
| Lowest | 0-1.2 | 16,016 (19.9) | 815 (23.5) | |
| Second | 1.2-1.7 | 15,984 (19.9) | 696 (20.1) | |
| Third | 1.7-2.4 | 16,136 (20.0) | 691 (19.9) | |
| Fourth | 2.4-3.3 | 16,119 (20.0) | 647 (18.6) | |
| Highest | 3.3-13.3 | 16,196 (20.1) | 622 (17.9) | |
| Mean±SD | 2.3 ± 1.3 | 2.3 ± 1.3 | 2.2 ± 1.3 | <0.001 |
*
The ranges of intake for the quintile categories of fiber, fruit and vegetable intake are non-overlapping ranges.