Impact of comorbidities on patient-reported outcomes in psoriatic arthritis: a single centre cohort study

Comorbidities are frequent in psoriatic arthritis (PsA) and may contribute to worse health-related outcomes. Patient-reported outcomes (PROs) are used to evaluate the burden of the assessed disease. The aim of this study is to evaluate the impact of comorbidities on selected PROs in PsA.

Adult patients, diagnosed with PsA, based on CASPAR criteria, were included in this cross-sectional, observational study. Collected data encompassed the comorbidities and PROs (Health Assessment Questionnaire [HAQ], Multi-Dimensional Health Assessment Questionnaire [MDHAQ], 36-Item Short Form Health Survey [SF-36]). Standard statistic methods were performed for data assessment.

There were 267 participants included in the study (54.7% females). The most prevalent comorbidities were cardiovascular diseases (CVD) (29.2 %). Multimorbidity was observed in 50.2% cases and was associated with poorer results of SF-36 questionnaire, regarding bodily pain (34.7 [30.1, 39.3] vs. 47.5 [43.1, 52.0]; p<0.01), physical functioning (52.1 [47.3, 56.9] vs. 63.1 [58.9, 67.4]; p<0.01) and role physical (28.5 [21.2, 35.9] vs. 42.8 [35.2, 50.4]; p<0.01). CVD were associated with poorer MDHAQFn score (β=0.17, p<0.01), while mental disorders negatively influenced mental health (β= -0.35, p<0.01), vitality (β= -0.22, p<0.01), general health (β= -0.19, p<0.01), social functioning (β= -0.15, p=0.04) and role emotional (β= -0.30, p<0.01) dimensions of SF-36.

Multimorbidity exerts significant impact on physical aspects of quality of life (QoL) in PsA. CVD and mental disorders adversely influence functional capacity as well as mental and social dimensions of QoL, respectively. The impact of comorbidities should be taken into account by clinicians and researchers assessing PROs.