Table 1.

Leptin concentrations (ng/ml) and the relationships with carotid artery plaque (per 1 SD increment) in all RA patients and subgroups. Univariate comparisons of leptin concentrations between subgroups were made using the Mann-Whitney U test and univariate associations of leptin concentrations with plaque in logistic regression models. Major risk factors comprised hypertension, dyslipidemia, smoking, and diabetes2.

GroupsNumberConcentrationsRelationships with Plaque
CrudeIndependent
Median (IQR)pp*OR (95% CI)pOR (95% CI)p
All21710.2 (5.5–18.5)1.00 (0.99–1.01)0.41.00 (0.99–1.01)0.3
Population
  Black11212.4 (6.3–21.4)1.01 (0.99–1.02)0.41.01 (0.99–1.02)0.5
  White1058.4 (4.9–14.3)0.0010.20.96 (0.65–1.43)0.81.00 (0.67–1.50)1
Age ≥ 50 yrs
  Yes16910.1 (5.5–18.4)1.00 (0.99–1.01)0.51.00 (0.99–1.01)0.4
  No4810.8 (5.2–20.0)0.90.31.05 (0.86–1.28)0.61.03 (0.88–1.21)0.7
Age > 55 yrs
  Yes1279.5 (5.5–17.8)1.00 (0.99–1.01)0.91.00 (0.99–1.01)1
  No9011.6 (5.5–21.2)0.40.11.01 (0.99–1.03)0.41.01 (0.99–1.02)0.5
≥ 1 major risk factor
  Yes15111.2 (5.7–20.9)1.53 (0.82–2.84)0.22.75 (1.19–6.37)0.01
  No589.0 (3.8–15.3)0.030.51.00 (0.99–1.01)11.00 (0.99–1.01)0.6
  Missing8
Obesity
  Yes6418.2 (9.5–27.6)0.99 (0.98–1.01)0.51.00 (0.98–1.01)0.7
  No1477.5 (4.6–13.3)< 0.00010.91.01 (1.00–1.02)0.091.01 (1.00–1.02)0.1
  Missing6
MetS waist
  Yes10015.0 (8.2–23.3)0.99 (0.98–1.01)0.61.00 (0.98–1.01)0.5
  No1146.9 (4.3–12.4)< 0.00010.71.01 (0.99–1.02)0.091.01 (1.00–1.02)0.1
  Missing3
RA duration > 10 yrs
  Yes1169.8 (4.9–17.8)1.01 (0.99–1.02)0.21.01 (1.00–1.02)0.2
  No10010.6 (5.9–20.4)0.30.81.00 (0.98–1.01)0.91.00 (0.99–1.01)1
  Missing1
CDAI > 10
  Yes929.4 (5.4–18.3)1.00 (0.99–1.02)0.71.00 (0.98–1.02)1
  No12410.3 (5.2–21.2)0.30.81.00 (0.99–1.02)0.41.01 (1.00–1.02)0.3
  Missing1
ESR > 12 mm/h
  Yes10610.03 (5.9–19.3)1.05 (0.96–1.13)0.31.05 (0.96–1.14)0.3
  No1059.2 (5.2–18.0)0.40.091.00 (0.99–1.01)0.81.00 (1.00–1.01)0.8
  Missing6
Deformed joints
  Yes16510.0 (5.4–17.9)1.00 (0.99–1.01)0.71.00 (0.99–1.02)0.7
  No5111.9 (5.5–22.4)0.30.061.00 (0.99–1.02)0.61.01 (0.99–1.03)0.4
  Missing1
RF-positive
  Yes1689.5 (5.4–18.5)1.01 (0.99–1.02)0.11.01 (1.00–1.02)0.2
  No4812.7 (6.7–19.4)0.30.91.00 (0.98–1.01)0.51.00 (0.98–1.01)0.8
  Missing1
  • * p value for associations in age at disease onset, sex, race (except for in models by population grouping), body mass index, glomerular filtration rate, and cardiovascular drug use adjusted linear regression models.

  • p value for associations in Framingham score, race, glomerular filtration rate, body mass index, and C-reactive protein adjusted logistic regression models. Significant associations are shown in bold face. RA: rheumatoid arthritis; IQR: interquartile range; MetS: metabolic syndrome; CDAI: Clinical Disease Activity Index; ESR: erythrocyte sedimentation rate; RF: rheumatoid factor.