Table 3

Associations of proinsulin-processing metabolites with RA features

Β-coefficient (95% CI)


Insulin and C-peptide (dependent variables)


logInsulin pM

P

logC-peptide

P


RA versus controls (β 95% CI for RA, 101, and controls, 99)

0.39 (0.14-0.64)

0.00

0.61 (0.32-0.91)

0.00

GC-RA versus controls (β 95% CI for RA, 56, and controls, 99)

0.14 (0.01-0.27)

0.04

0.20 (0.02-0.38)

0.03

GC+RA versus controls (β 95% CI for RA, 55, and controls, 99)

0.15 (0.06-0.25)

0.00

0.29 (0.17-0.40)

0.00

RA patients features (β 95% CI for RA, 101)

Disease duration

-0.79 (-3.32-1.74)

0.54

-0.01 (-0.02-0.00)

0.07

RF positivity

-10. 9 (-46.9-25.2)

0.99

0.03 (-0.06-0.12)

0.51

ESR

-0.50 (-1.49-0.50)

0.33

-0.00 (-0.01-0.00)

0.12

CRP

-0.21 (-1.34-0.91)

0.03

0.00 (-0.00-0.00)

0.65

Current prednisone

0.13 (-0.23-0.48)

0.48

0.10 (0.01-0.18)

0.02

Prednisone, mg/day/previous 3 months

-3.28 (-22.36-15.80)

0.25

-0.02 (-0.05-0.02)

0.16

HAQ

3.03 (-20.32-26.37)

0.63

-0.02 (-0.09-0.05)

0.69

DAS28

-0.21 (-10.89-10.49)

0.67

0.00 (-0.03-0.03)

0.99

Current nonbiologic DMARD

23.58 (-63.53-110.68)

0.79

0.05 (-0.13-0.23)

0.61

logIntact proinsulin (dependent variable)


Intact proinsulin

p

Intact proinsulin/C-peptide ratio

p


RA versus controls (β 95% CI for RA, 101, and controls, 99)

0.81 (0.13-1.46)

0.02

0.55 (0.05-1.05)

0.03

GC-RA versus controls (β 95% CI for RA, 56, and controls, 99)

0.34 (0.05-0.62)

0.02

1.65 (-0.06-3.35)

0.06

GC+RA versus controls (β 95% CI for RA, 55, and controls, 99)

0.24 (0.05-0.43)

0.01

0.14 (-0.04-0.33)

0.13

RA patients features (β 95% CI for RA, 101)

Disease duration

0.03 (-0.46-0.51)

0.83

0.13 (-0.45-0.71)

0.96

RF positivity

3.4 (0.25-6.51)

0.11

3.45 (-0.34-7.25)

0.15

ESR

-0.03 (-0.12-0.06)

0.92

0.01 (-0.11-0.10)

0.62

CRP

0.02 (-0.07-0.12)

0.50

0.03 (-0.08-0.14)

0.47

Current prednisone

-0.07 (-0.73-0.59)

0.83

-1.40 (-5.30-2.50)

0.48

Prednisone. mg/day/previous 3 months

-0.11 (-1.86-1.65)

0.82

-0.05 (-1.83-1.73)

0.63

HAQ

0.62 (-2.13-3.37)

0.75

1.23 (-1.99-4.46)

0.85

DAS28

0.49 (-0.74-1.72)

0.65

0.39 (-1.03-1.82)

0.68

Current nonbiologic DMARD

2.93 (-7.52-13.34)

0.91

3.40 (-7.45-14.26)

0.96

logSplit proinsulin (dependent variable)


Split proinsulin

P

Split proinsulin/C-peptide ratio

P


RA versus controls (β 95% CI for RA, 101, and controls, 99)

0.70 (0.38-1.02)

0.00

0.57 (0.30-0.88)

0.00

GC-RA versus controls (β 95% CI for RA, 56, and controls, 99)

0.19 (0.00-0.36)

0.04

0.16 (-0.02-0.34)

0.08

GC+RA versus controls (β 95% CI for RA, 55, and controls, 99)

0.33 (0.20-0.45)

0.00

0.25 (0.12-0.38)

0.00

RA patients features (β 95% CI for RA, 101)

Disease duration

-1.58 (-2.84-0.31)

0.01

-1.82 (-3.48-0.17)

0.02

RF positivity

2.83 (-8.33-13.98)

0.60

5.11 (-8.54-18.76)

0.67

ESR

0.08 (-0.39-0.22)

0.60

-0.02 (-0.39-0.35)

0.93

CRP

0.16 (-0.18-0.51)

0.42

0.20 (-0.23-0.62)

0.33

Current prednisone

0.57 (0.18-0.96)

0.00

0.41 (0.05-0.76)

0.03

Prednisone. mg/day/previous 3 months

-1.04 (-6.99-4.91)

0.98

-0.14 (-6.50-6.22)

0.71

HAQ

-3.17 (-11.15-4.81)

0.11

-0.35 (-10.84-10.14)

0.43

DAS28

1.11 (-2.89-5.11)

0.82

-1.79 (-3.01-6.67)

0.67

Current nonbiologic DMARD

15.28 (-15.93-46.49)

0.83

15.43 (-17.36-48.23)

0.73


All β coefficients are adjusted for sex, age, and body mass index. All dependent variables are considered log transformed. Rheumatoid factor (RF) positivity, current prednisone and current nonbiologic DMARD are consider dichotomous variables. For abbreviations and units, see Table 1. Significant associations (P < 0.05) are depicted in bold

Ferraz-Amaro et al. Arthritis Research & Therapy 2013 15:R17   doi:10.1186/ar4149

Open Data