Table 1.

Baseline characteristics. Data are n (%) unless otherwise indicated.

Cohort VariablesRA Plus General ControlsRA Plus OA Controls
RA Population, n = 1522General Controls, n = 6511pRA Population, n = 1746OA Controls, n = 2554p
Mean (SD) age, yrs63.0 (10.4)63.6 (10.1)0.040363.8 (10.3)63.4 (10.9)0.2371
Age category, yrs, mean (SD)
  < 50137 (9.0)533 (8.2)0.1839139 (8.0)264 (10.3)0.043
  50–59442 (29.0)1774 (27.2)470 (26.9)671 (26.3)
  60–69529 (34.8)2278 (35.0)618 (35.4)845 (33.1)
  ≥ 70414 (27.2)1926 (29.6)519 (29.7)774 (30.3)
Race/ethnicity< 0.00010.0008
  White721 (47.4)3283 (50.4)833 (47.7)1339 (52.4)
  Hispanic448 (29.4)1642 (25.2)505 (28.9)624 (24.4)
  Black/African American198 (13.0)752 (11.5)233 (13.3)365 (14.3)
  Asian/Pacific Islander135 (8.9)792 (12.2)152 (8.7)210 (8.2)
  Other/unknown20 (1.3)42 (0.6)23 (1.3)16 (0.6)
  Female1105 (72.6)4632 (71.1)0.25621305 (74.7)1954 (76.5)0.1845
Number of Charlson Comorbidity Index excluding rheumatic or CV diseases
  0936 (61.5)4206 (64.6)0.01581070 (61.3)1625 (63.6)0.0651
  1494 (32.5)1872 (28.8)563 (32.2)742 (29.1)
  2 or more92 (6.0)433 (6.7)113 (6.5)187 (7.3)
Smoking status
  Smoker159 (10.4)569 (8.7)0.0036171 (9.8)207 (8.1)0.1404
  Nonsmoker1230 (80.8)5210 (80.0)1430 (81.9)2120 (83.0)
  Unknown133 (8.7)732 (11.2)145 (8.3)227 (8.9)
BMI category
  Obese (≥ 30)516 (33.9)1950 (29.9)0.0742557 (31.9)998 (39.1)< 0.0001
  Overweight (25–29.9)359 (23.6)1612 (24.8)404 (23.1)555 (21.7)
  Normal (< 25)229 (15.0)904 (13.9)260 (14.9)276 (10.8)
  Unknown418 (27.5)2045 (31.4)525 (30.1)725 (28.4)
Baseline CV risk stratification*
  Low114 (7.5)650 (10.0)0.0033126 (7.2)232 (9.1)0.007
  Medium780 (51.2)3382 (51.9)916 (52.5)1397 (54.7)
  High628 (41.3)2479 (38.1)704 (40.3)925 (36.2)
  Diabetes622 (40.9)2440 (37.5)0.0142695 (39.8)912 (35.7)0.0064
  10 year risk > 20%§16 (1.1)62 (1.0)0.722920 (1.1)21 (0.8)0.2841
  HTN1130 (74.2)4079 (62.6)< 0.00011316 (75.4)1737 (68.0)< 0.0001
  HTN diagnosis1152 (75.7)4945 (75.9)0.00051343 (76.9)2045 (80.1)0.013
  Anti-HTN medication use1203 (79.0)5102 (78.4)< 0.00011400 (80.2)2063 (80.8)0.6302
Baseline lipid panel, mean (SD)1447609016592400
  LDL-C, in mg/dl104.6 (34.4)109.6 (37.6)< 0.0001104.5 (34.0)109.8 (35.3)< 0.0001
  LDL-C, in mmol/l2.70 (0.89)2.83 (0.97)2.70 (0.88)2.84 (0.91)
  HDL-C, in mg/dl51.0 (14.0)50.8 (13.5)0.690351.6 (14.2)51.4 (13.3)0.5969
  HDL-C, in mmol/l1.32 (0.36)1.31 (0.35)1.33 (0.37)1.33 (0.34)
  Triglycerides, in mg/dl150.6 (81.2)158.8 (90.4)0.002150.2 (80.5)156.9 (82.0)0.0113
  Triglycerides, in mmol/l1.70 (0.92)1.79 (1.02)1.70 (0.91)1.77 (0.93)
  Total cholesterol, in mg/dl185.1 (41.2)191.8 (44.5)< 0.0001185.6 (40.8)192.0 (42.0)< 0.0001
  Total cholesterol, in mmol/dl4.79 (1.07)4.96 (1.15)4.80 (1.06)4.97 (1.09)
  • * CV risk stratification; low = 0–1 risk factor; medium = 2+ risk factors and 10-year risk ≤ 20%; high = coronary heart disease (CHD) or CHD equivalents; risk factors include smoking, HTN, LDL-C or HDL-C, and age (men ≥ 45 yrs, women ≥ 55 yrs).

  • § Framingham risk scoring was used considering risk factors of age, total cholesterol, HDL-C, systolic blood pressure, treatment for HTN, and smoking18. RA: rheumatoid arthritis; OA: osteoarthritis; LDL-C: low-density lipoprotein cholesterol; HDL-C: high-density lipoprotein cholesterol; CV: cardiovascular; HTN: hypertension; BMI: body mass index.