Table 2.

Selected characteristics [medians (interquartile range) or percent] by quartile of circulating DBP concentration in the CPS-II cohort

Q1Q2Q3Q4
Characteristics(<272 μg/mL)(272–<294 μg/mL)(294–<334 μg/mL)(≥334 μg/mL)Pa
Age, y71.6 (66.1–75.9)72.5 (68.3–76.0)70.1 (65.4–74.9)67.8 (64.0–73.8)0.06
Male (%)74.072.664.138.20.003
Race (%)
 White96.098.097.4100.00.69
BMIb (kg/m2)27.3 (23.6–29.6)24.8 (23.0–27.4)25.1 (22.1–27.5)25.4 (23.2–28.2)0.09
Smoking statusb (%)
 Never37.042.236.853.10.52
 Former63.055.657.943.8
 Current0.02.25.33.1
History of diabetesb (%)22.013.712.82.90.10
History of kidney failurec (%)0002.90.25
Physical activityb (MET-h/wk)14.0 (7.0–26.5)14.0 (7.0–24.5)14.0 (7.0–24.0)13.9 (7.0–29.0)0.89
College graduatec (%)62.051.038.545.50.77
Intake/dayb
 Total energy (kcal)1,881 (1,445–2,254)1,842 (1,538–2,159)1,719 (1,378–2,082)1,628 (1,495–2,137)0.56
 Dietary vitamin D (IU)178 (141–283)183 (114–303)167 (125–283)188 (160–220)0.85
 Dietary calcium (mg)738 (630–945)786 (539–1,144)671 (500–1,133)742 (633–1,115)0.81
 Alcohol (drinks)0.17 (0–0.87)0.20 (0–1.13)0.07 (0–0.37)0.07 (0–0.60)0.38
Use of dietary supplementsb (%)
 Vitamin D11.99.86.522.30.29
 Calcium36.625.642.948.30.21
Family history of kidney cancerc (%)002.62.90.42
Family history of any other cancerb (%)60.051.064.179.40.07
  • aThe χ2 test or Fisher exact test (when cells have expected counts <5) for categorical variables and Wilcoxon test for continuous variables.

  • bAssessed at the time closest to blood collection.

  • cAssessed at baseline in 1982.