Table 2. Characteristics of included studies.
| Study | Region | Setting | Follow-up (median, y) | Exposure/outcome | Sample size/age range (y)/male (%) |
Analysis model | RR (95%CI) | Covariates adjustment | |
| Exposed | Control | ||||||||
| Aletaha-2019 | USA | Health-claims database | 2006-2015/2.5-2.8 | PsO/UV | 115141/18-64/NM | 74228131/18-64/NM | Cox proportional hazards model | 1.4 (1.2-1.7) | Age, sex, insurance, region |
| PsA/UV | 8406/18-64/NM | 5380715/18-64/NM | 4.0 (2.9-5.6) | ||||||
| UV/PsO | 34422/18-64/NM | 22166447/18-64/NM | 1.6 (1.3-1.8) | ||||||
| UV/PsA | 4.8 (3.9-6.0) | ||||||||
| Brandon-2018 | USA | Health-claims database | 2000-2013/5.3 | PsO/UV | 4312/0-16/34.4 | 43120/0-16/34.4 | Poisson regression model | 1.35 (0.52-2.94) | Age, sex |
| PsA/UV | 212/0-16/44.8 | 2120/0-16/44.8 | 22.36 (7.04-54.75) | ||||||
| Charlton-2018 | UK | Population-based | 1998-2014/NMa | PsA/UV | 6783/18-89/49.5 | 27132/18-89/49.5 | Poisson regression model | 3.55 (2.21-5.70) | Age, sex, smoking, BMI |
| Chi-2017 | Taiwan, China | Population-based | 2000-2011/7.3 | PsO/UV | 137847/all/58.6 | 147954/All/58.8 | Cox proportional hazards model | 1.16 (1.06-1.26) | Age, sex, comorbidities |
| PsA/UV | 10107/all/62.3 | 1.95 (1.61-2.37) | |||||||
| Egeberg-2015 | Denmark | Population-based | 1997-2011/NMb | PsO/UV | 67394/≥18/48.9 | 5434749/≥18/49.4 | Poisson regression model | 2.13 (1.76-2.59)c | Age, sex, comorbidities, socioeconomic status |
| PsA/UV | 6735/≥18/43.7 | 2.50 (1.53-4.08) | |||||||
| UV/PsO | 13114/≥18/48.6 | 5495764/≥18/49.4 | 1.73 (1.46-2.04)c | ||||||
| UV/PsA | 3.77 (2.66-5.34) | ||||||||
| Kaine-2018 | USA | Health-claims database | 2008-2015/3.0 | PsA/UV | 14898/≥18/44.6 | 35037/≥18/44.4 | Cox proportional hazards model | 2.21 (1.64-2.98) | Age, sex, calendar year of diagnosis, region |
BMI: Body mass index; NM: Not mention; PsA: Psoriatic arthritis; PsO: Psoriasis; RR: Rate ratio; UV: Uveitis. awith a mean follow-up of 5.5y; bwith a maximum follow-up of 15y; ccrude RR.