Table 1.
Age-adjusted baseline characteristics of the cohorts according to presence or absence of history of kidney stones
| HPFS | NHS I | NHS II | ||||
|---|---|---|---|---|---|---|
| No stones (n = 42,231) |
Stones (n = 3,517) |
No stones (n = 86,414) |
Stones (n = 3,821) |
No stones (n = 102,633) |
Stones (n = 3,489) |
|
| Age, years* | 53.7(9.7) | 55.8(9.4) | 58.4(7.1) | 59.0(7.0) | 36.6(4.6) | 37.4(4.5) |
| White race, No. (%) | 40,013(95) | 3,342(95) | 80,878(94) | 3,594(94) | 95,500(93) | 3,293(94) |
| Family history of CHD, No. (%) | 13,488(32) | 1,211(33) | 31,435(36) | 1,527(39) | 22,276(22) | 892(25) |
| BMI (kg/m2) | ||||||
| <20.0, No. (%) | 596(1) | 44(1) | 4,354(5) | 193(6) | 12,850(13) | 391(12) |
| 20.0–24.9, No. (%) | 13,123(32) | 968(28) | 26,886(33) | 1,004(28) | 44,333(44) | 1,311(40) |
| 25.0–29.9, No. (%) | 22,692(55) | 1,954(57) | 30,635(38) | 1,302(36) | 25,980(26) | 912(26) |
| ≥30.0, No. (%) | 4,837(12) | 482(14) | 19,466(24) | 1,096(31) | 16,583(17) | 775(22) |
| Smoking status | ||||||
| Never, No. (%) | 19,332(48) | 1,620(49) | 38,189(44) | 1,589(42) | 67,168(65) | 2,197(64) |
| Past, No. (%) | 17,125(42) | 1,463(42) | 34,708(40) | 1,587(41) | 22,807(22) | 737(21) |
| Current, No. (%) | 4,112(10) | 302(9) | 13,316(15) | 638(17) | 12,525(12) | 551(16) |
| Physical activity (METS/week) | ||||||
| <3, No. (%) | 8,628(20) | 762(22) | 13,520(16) | 656(17) | 14,795(14) | 541(15) |
| 3–8, No. (%) | 9,480(22) | 839(24) | 16,956(20) | 769(20) | 22,892(22) | 779(22) |
| 9–17, No. (%) | 7,544(18) | 614(17) | 16,228(19) | 721(19) | 21,271(21) | 740(21) |
| 18–27, No. (%) | 5,359(13) | 465(13) | 10,225(12) | 424(11) | 12,849(13) | 357(10) |
| >27, No. (%) | 11,220(27) | 837(24) | 16,907(20) | 679(18) | 23,502(23) | 833(25) |
| Diabetes, No. (%) | 1,122(3) | 121(3) | 4,418(5) | 324(8) | 977(1) | 63(2) |
| High blood pressure, No. (%) | 8,570(20) | 932(25) | 28,402(33) | 1,605(41) | 6,519(6) | 394(10) |
| Gout, No. (%) | 1,882(4) | 319(8) | 1,688(2) | 144(4) | 449(1)¶ | 83(1)¶ |
| Elevated cholesterol, No. (%) | 4,492(11) | 466(13) | 27,201(32) | 1,346(35) | 9,665(9) | 472(13) |
| Aspirin use, No. (%) | 11,434(27) | 1,009(28) | 20,410(24) | 886(23) | 11,428(11) | 455(13) |
| Thiazide use, No. (%) | 3,689(9) | 450(12) | 9,352(11) | 536(14) | 1,774(2) | 155(4) |
| Loop diuretics use, No. (%) | 331(1) | 41(1) | 1,428(2)¶ | 132(3)¶ | 424(0) | 38(1) |
| Oral steroids use, No. (%) | 268(1)¶ | 42(1)¶ | 1,536(2)¶ | 112(3)¶ | 1,089(1)¶ | 149(3)¶ |
| Lipid-lowering drugs use, No. (%) | 218(1) | 21(1) | 1,428(2) | 71(2) | 4,075(4)¶ | 385(7)¶ |
| Calcium channel blockers use, No. (%) | 406(1) | 47(1) | 1,601(2) | 117(3) | 1,604(2)¶ | 171(3)¶ |
| Beta blockers use, No. (%) | 3,244(8) | 398(10) | 5,957(7) | 343(9) | 2,128(2) | 131(4) |
| ACE inhibitors use, No. (%) | 2,509(11)¶ | 480(13)¶ | 1,745(2) | 117(3) | 2,921(3)¶ | 280(5)¶ |
| Other anti-hypertensive drugs, No. (%) | 1,238(3) | 145(4) | 1,434(2) | 90(2) | 1,438(1) | 104(3) |
| Calcium intake, mg/day | 798(399) | 725(360) | 800(382) | 751(369) | 879(399) | 821(380) |
| Potassium intake, mg/day | 3403(1114) | 3220(1071) | 3073(954) | 2981(976) | 2906(947) | 2842(948) |
| Magnesium intake, mg/day | 350(121) | 330(115) | 324(118) | 311(116) | 312(108) | 301(106) |
| Animal protein intake, g/day | 67.1(25.7) | 64.5(24.4) | 59.8(22.0) | 59.0(22.2) | 63.3(23.6) | 63.4(24.0) |
| Total fat intake, g/day | 71.6(27.9) | 71.6(28.2) | 61.3(22.5) | 61.8(23.2) | 62.7(22.3) | 63.6(22.8) |
| Caffeine intake, mg/day | 234(230) | 211(210) | 266(222) | 238(215) | 238(215) | 224(205) |
| Vitamin D intake, IU/day | 398(302) | 361(282) | 359(257) | 341(248) | 379(253) | 354(251) |
| DASH-score | 24(5) | 23(5) | 24(5) | 23(5) | 24(5) | 23(5) |
| Alcohol intake, g/day# | 6.0(0.9, 15.0) | 4.4(0.0, 13.0) | 1.1(0.0, 6.0) | 0.9(0.0, 4.4) | 0.9(0.0, 3.5) | 0.9(0.0, 2.8) |
| Post-menopause, No. (%) | N.A. | N.A. | 72,356(84) | 3,324(85) | 3,277(3) | 200(5) |
| Post-menopausal hormone use | ||||||
| Missing/pre-menopause, No. (%) | N.A. | N.A. | 20,377(24) | 784(22) | 8,041(8) | 266(8) |
| Never used, No. (%) | N.A. | N.A. | 23,788(28) | 1,059(27) | 81,517(79) | 2,575(75) |
| Past user, No. (%) | N.A. | N.A. | 28,957(34) | 1,279(33) | 8,815(9) | 399(11) |
| Current user, No. (%) | N.A. | N.A. | 13,292(15) | 699(18) | 4,260(4) | 249(7) |
| Region | ||||||
| West, No. (%) | 9,188(22) | 688(20) | 10,508(12) | 375(10) | 14,986(15) | 438(13) |
| Midwest, No. (%) | 11,530(27) | 908(26) | 16,163(19) | 732(19) | 34,323(33) | 1,157(33) |
| South, No. (%) | 11,253(27) | 1,067(30) | 9,251(11) | 447(12) | 17,515(17) | 684(20) |
| Northeast, No. (%) | 9,742(23) | 809(23) | 50,492(58) | 2,267(59) | 35,568(35) | 1,205(35) |
Values are means(SD) or percentages except where otherwise specified and are standardized to the age distribution of the study population.
*
Value is not age-adjusted.
#
Median (25th, 75th percentiles).
¶
Baseline values not available, first available value reported. Some percentages may not add up to 100% due to rounding or missing values. ACE, angiotensin converting enzyme, N.A., not available. Time at risk goes from 1986 to 2010 for HPFS, 1991 to 2009 for NHS II, 1992 to 2010 for NHS I.