Background Rheumatoid arthritis (RA) patients are more likely to experience depression.¹ This comorbidity is associated with increased disability, use of healthcare services, and mortality risk.^2,3 The association between RA and other mental health disorders has received limited attention and there remains a need to further demonstrate and understand the impact of RA on mental health.

Objectives Evaluate the mental health burden of RA patients based on the analysis of Short Form-36v2 Health Survey (SF-36v2) mental health (MH) and role emotional (RE) domain scores from two independent general population databases in the US and Europe.

Methods The mental health burden associated with RA was analyzed by comparing mean SF-36v2 MH and RE scores of individuals self-reporting RA (with or without depression) and the scores from 2 benchmark samples (individuals without RA, individuals with depression and no RA) in two large cross-sectional survey studies (QualityMetric's 2009 General US Population Norming Study of the SF-36v2 and the 2014 European National Health and Wellness Survey). Multivariate regression methods were used to adjust each benchmark sample to the distribution of the RA sample in terms of age and gender. Differences between samples were interpreted with respect to minimally important differences: 3 points for MH; 4 points for RE.

Results The US (2009) and European (2014) samples included 4,042 and 81,366 individuals, respectively. Compared with individuals without RA or depression, mean RE scores were significantly (P<0.001) lower for RA patients without depression in the US (-7.75 points) and Europe (-5.31 points). Likewise, mean MH scores were significantly (P<0.001) lower among RA patients without depression in the US (-4.85 points) and Europe (-5.03 points) compared with individuals without RA or depression. Compared to individuals with depression and no RA, mean RE and MH scores were 5 to 10 points higher (P<0.001) for RA patients without depression in both the US and Europe. Comparisons of RE and MH scores between RA patients with and without comorbid depression showed that comorbid depression was associated with 2 to 6 points lower scores (P<0.01) in RE and MH domains, in both the US and Europe.

Conclusions RA is associated with significant and clinically meaningful mental health burden as measured by SF-36v2 MH and RE domains. Results comparing scores between RA patients with and without comorbid depression suggest that there is an incremental mental health burden associated with RA, often exceeding minimally important differences among US patients.

References

1. Dickens C, et al. Psychosomatics. 2003;44(3):209–215.

2. Ang DC, et al. J Rheumatol. 2005;32(6):1013–1019.

3. Kessler RC, et al. J Occupat Environ Med. 2003;45(12):1257–1266.

References

Disclosure of Interest V. Strand Consultant for: Abbvie, Amgen, AstraZeneca, BiogenIdec, Boehringer Ingelheim, Celltrion, Crescendo, Genentech/Roche, GSK, Janssen, Lilly, Merck, Novartis, Pfizer, Regeneron, Samsung, Sanofi and UCB, M. Kosinski Employee of: Optum, R. Rendas-Baum Employee of: Optum, D. Brooks Shareholder of: GlaxoSmithKline, Employee of: GlaxoSmithKline, R. Ganguly Shareholder of: GlaxoSmithKline, Employee of: GlaxoSmithKline