Background/Purpose: Shared inflammatory processes underscore a substantial burden and risk of psychiatric complications – namely depression and anxiety – in patients with psoriatic arthritis (PsA), yet to our knowledge there is no synthesis of the evidence to date. We conducted a systematic review and meta-analysis with the following aims: 1) determine the prevalence and incidence of depression and/or anxiety; 2) assess the impact of depression and/or anxiety on patient outcomes; and 3) describe treatment of depression and/or anxiety among patients with PsA.

Methods: We conducted a systematic literature review of Medline, Embase, Cochrane Database of Systematic Reviews, CINAHL and PsycINFO. We included full-length studies that: 1) utilized an observational design; 2) involved a sample of patients with PsA, with/without a comparator group; 3) reported depression and/or anxiety as an outcome, comorbidity, or predictor of a health outcome; and 4) reported relevant estimates (e.g. prevalence proportion, odds ratio, hazard ratio) or sufficient data to allow calculation.  We extracted information on study setting and design, sample size, methods of assessing depression and anxiety and reported prevalence and incidence of depression and/or anxiety. When relevant data was provided, we pooled estimates using random effects models.

Results: Of 683 titles identified in our search 10 studies met inclusion criteria. Several methods were used to assess depression and anxiety including the Hospital Anxiety and Depression Scale (HADS), Patient Health Questionnaire (PHQ-9) and International Classification of Diseases 9^th Revision Codes (ICD-9).  The majority of included studies assessed the prevalence of psychiatric complications; the pooled prevalence proportion of depression based on 6 studies and a total of 22,163 PsA patients was 20% (95% confidence interval (CI), 15% to 25%) and the pooled prevalence proportion of anxiety based on 4 studies and 15,878 PsA patients was 27% (95% CI, 12% to 43%) (Figure 1). The incidence of depression in PsA patients as compared to the general population was reported in 3 studies and meta-analysis yielded a pooled incidence rate ratio (IRR) of 1.34 (95% CI, 1.20 to 1.49). Depression and anxiety were reported to be associated with increased inflamed joint count, pain, disability and fatigue. Treatment for depression in PsA patients included antidepressant/anxiolytic medications and/or psychotherapy. In studies reporting antidepressants use, only a small minority of patients take antidepressants.

Conclusion: We found a high prevalence of depression and anxiety in patients with PsA, and 30% higher risk of incident depression as compared to the general population. A clinical approach that includes screening and early treatment of psychiatric complications by health care professionals may impact mental health in patients with PsA.