Table 1.
Characteristics of included studies.
| Author (year) | country | study design | Age | Gender | NOS | Sample size | Method of weight/height | BMI category | OR(RR)(95%CI) | Adjustment factors | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| RA/Control | (kg/m2) | Men | Women | ||||||||
| Voigt, 1994 | USA | Case-control | 18-64 | Women | 7 | 349/1457 | Self-reported | premenopausal | NA | Age, smoking status | |
| 12.94-20.43 | 1.00 | ||||||||||
| 20.44-22.51 | 1.10(0.70-1.60) | ||||||||||
| 22.52-25.82 | 1.00(0.70-1.60) | ||||||||||
| 25.83-52.86 | 1.50(1.00-2.30) | ||||||||||
| postmenopausal | |||||||||||
| 12.94-20.43 | 1.00 | ||||||||||
| 20.44-22.51 | 1.10(0.50-2.10) | ||||||||||
| 22.52-25.82 | 1.40(0.70-2.60) | ||||||||||
| 25.83-52.86 | 1.40(0.70-2.60) | ||||||||||
|
| |||||||||||
| Symmons, 1997 | UK | Case-control | 18-70 | Mixed | 7 | 90/93 | Self-reported | 20.0-24.9 | Mixed | 1.00 | Smoking status, social class |
| 25.0-29.9 | 1.08(0.54-2.16) | ||||||||||
| 30.0 -40.0 | 3.74(1.14-12.27) | ||||||||||
|
| |||||||||||
| Uhlig, 1999 | Norway | Case-control | 20-79 | Mixed | 7 | 347/5725 | Self-reported | <25.0 | Mixed | 1.00 | Age, sex, marital status, employment category, formal education, current smoking status. |
| 25.0-29.9 | 1.09(0.80-1.48) | ||||||||||
| ≥30.0 | 1.54(0.91-2.58) | ||||||||||
|
| |||||||||||
| Pedersen, 2006 | Denmark | Case-control | 18-65 | Mixed | 6 | 505/752 | Self-reported | <18.5 | 0.95(0.19-4.72) | 0.95(0.52-1.73) | Birth year, year of RA diagnosis, gender |
| 18.5-25.0 | 1.00 | 1.00 | |||||||||
| 25.0-30.0 | 0.86(0.54-1.37) | 1.26(0.87-1.85) | |||||||||
| >30.0 | 1.39(0.71-2.71) | 1.83(0.97-3.44) | |||||||||
|
| |||||||||||
| Rodriguez, 2009 | UK | Case-control | 20-79 | Mixed | 8 | 559/4234 | Measured | <20.0 | Mixed | 0.65(0.43-0.98) | Age, sex, calendar year, number of referrals, and visits to a primary care physician |
| 20.0-24.9 | 1.00 | ||||||||||
| 25.0-30.0 | 1.18(0.94-1.98) | ||||||||||
| >30 | 0.95(0.68-1.34) | ||||||||||
|
| |||||||||||
| Wesley, 2013 | Sweden | Case-control | 18-70 | Mixed | 7 | 2748/3444 | Self-reported | ACPA-Positive | Sex, age, area of residence, smoking, alcohol consumption, education |
||
| <25.0 | 1.00 | 1.00 | |||||||||
| 25.0-30.0 | 1.10(0.70-1.80) | 1.00(0.80-1.20) | |||||||||
| ≥30.0 | 0.60(0.30-0.90) | 1.00(0.80-1.20) | |||||||||
| ACPA-Negative | |||||||||||
| <25.0 | 1.00 | 1.00 | |||||||||
| 25.0-30.0 | 1.00(0.70-1.40) | 1.10(0.70-1.60) | |||||||||
| ≥30.0 | 1.10(0.60-1.80) | 1.60(1.20-2.20) | |||||||||
|
| |||||||||||
| Crowson, 2013 | USA | Case-control | ≥18 | Mixed | 5 | 813/813 | Measured | <30.0 | Mixed | 1.00 | Age, sex and calendar year, smoking status |
| ≥30.0 | 1.22(0.99-1.49) | ||||||||||
|
| |||||||||||
| Ljung, 2016 | Sweden | Case-control | 25-74 | Mixed | 7 | 557/1671 | Measured | <25.0 | 1.00 | 1.00 | Smoking habits, educational level, age, sex, year of health examination, cohort |
| 25.0-30.0 | 1.29(0.84-1.96) | 1.21(0.92-1.59) | |||||||||
| ≥30.0 | 1.78(1.01-3.12) | 1.37(0.96-1.95) | |||||||||
|
| |||||||||||
| Turesson, 2016 | Sweden | Case-control | 58 ± 7.2 | Mixed | 8 | MDCS (172/688) | Measured | MDCS | Smoking, level of formal education, alcohol consumption, socio-economic status | ||
| 18.5-25.0 | 1.00 | 1.00 | |||||||||
| 25.0-30.0 | 0.44(0.15-1.29) | 0.96(0.57-1.61) | |||||||||
| >30.0 | 0.14(0.01-1.44) | 0.96(0.48-1.92) | |||||||||
| MPMP (290/1160) | MPMP | ||||||||||
| 18.5-25.0 | 1.00 | 1.00 | |||||||||
| 25.0-30.0 | 0.75(0.46-1.20) | 1.67(0.94-2.69) | |||||||||
| >30.0 | 0.64(0.20-2.02) | 0.90(0.36-2.26) | |||||||||
|
| |||||||||||
| Fu, 2017 | China | Case-control | 18-75 | Mixed | 7 | 400/400 | Self-reported | <23.9 | Mixed | 1.00 | Sex |
| >24.0 | 1.26(0.95-1.66) | ||||||||||
|
| |||||||||||
| Wei, 2018 | China | Case-control | 30-75 | Mixed | 7 | 403/128 | Self-reported | <25.0 | Mixed | 1.00 | Age, sex, waist circumference, erosive osteoarthritis, duration of disease, current smoker, |
| 25.0-30.0 | 0.88(0.53-1.46) | ||||||||||
| ≥30.0 | 1.02(0.55-1.88) | ||||||||||
|
| |||||||||||
| Heliovaara, 1993 | Finland | Cohort | 30-69 | Men | 9 | 28364 | Measured | <25.0 | 1.00 | NA | Smoking, geographical region, type of population, marital status, social class, perceived, health, and age |
| 25.0-30.0 | 0.80(0.50-1.20) | ||||||||||
| >30.0 | 0.40(0.20-1.20) | ||||||||||
|
| |||||||||||
| Cerhan, 2002 | USA | Cohort | 55-69 | Women | 7 | 31336 | Self-reported | <23.4 | NA | 1.00 | Age |
| 23.4-25.8 | 0.88(0.56-1.37) | ||||||||||
| 25.9-29.2 | 0.99(0.64-1.53) | ||||||||||
| >29.2 | 1.01(0.65-1.56) | ||||||||||
|
| |||||||||||
| Harpsoe, 2014 | Denmark | Cohort | 27.4-33.3 | Women | 7 | 75008 | Self-reported | <18.5 | NA | 0.82(0.45-1.50) | Smoking status, alcohol consumption, parity, socio-occupational status |
| 18.5-25.0 | 1.00 | ||||||||||
| 25.0-30.0 | 1.12(0.85-1.49) | ||||||||||
| ≥30.0 | 1.53(1.07-2.18) | ||||||||||
|
| |||||||||||
| Lahiri, 2014 | UK | Cohort | 40-79 | Mixed | 9 | 25455 | Self-reported | <25.0 | Mixed | 1.00 | Age, gender, smoking status, breastfeeding, alcohol consumption |
| 25.0-30.0 | 1.16(0.78-1.74) | ||||||||||
| >30.0 | 1.49(0.91-2.42) | ||||||||||
|
| |||||||||||
| Lu, 2014 | USA | Cohort | NHS: 30-55 | Women | 7 | NHS:109896 | Measured | NHS | Age, community median income, smoking status, alcohol consumption, physical activity, parity, breastfeeding status, postmenopausal use, postmenopausal Hormone use | ||
| 18.5-24.9 | NA | 1.00 | |||||||||
| 25.0-29.9 | 1.16(0.99-1.35) | ||||||||||
| ≥30.0 | 1.12(0.92-1.37) | ||||||||||
| NHSII: 25-42 | NHS2:108727 | NHSII | |||||||||
| 18.5-24.9 | NA | 1.00 | |||||||||
| 25.0-29.9 | 1.68(1.30-2.17) | ||||||||||
| ≥30.0 | 1.72(1.31-2.45) | ||||||||||
BMI, body mass index; RR, relative risk; CI, confidence interval; NA, not available; M, men; W, women; NOS, New castale-Ottawa Scale; NHS, Nurses' Health Study.