Rheumatoid Arthritis: The Impact of Mental Health on Disease: A Narrative Review

Over 60% of rheumatoid arthritis (RA) patients achieve a good response after 12 months of treatment when following the European league against rheumatism (EULAR) guidelines for treatment. However, almost half of patients still suffer from moderate to severe disease activity despite this. In addition, mental health problems may remain despite reduced measures of inflammation systemically and within joints. Depression is two times more common in RA patients than in the general population, and intriguingly a bi-directional relationship with RA has been shown in cross-sectional studies. Chronic inflammation impairs the physiological responses to stress including effective coping behaviours, resulting in depression, which leads to a worse long-term outcome in RA. In RA patients, the pain score is not always solely related to inflammatory arthritis and immunological disease activity by Bak et al. (Patient Prefer Adherence 13:223-231, [1]). Non-inflammatory pain secondary to anxiety, depression, sleep disturbance and the psychosocial situation needs to be considered whilst fibromyalgia, mechanical pain and neuropathic pain can also contribute to overall pain scores by Chancay et al. (Women's Midlife Health 5:3, [2]). Hence, the UK National Institute for Health and Care Excellence (NICE) guideline for the management of RA included psychological interventions for fatigue, low mood and social well-being (NICE NG100, 2018) [3], and the NICE clinical guidelines (CG91) [4] suggest managing mental health and depression in chronic medical conditions to improve treatment outcomes. This is a narrative review of the impact of mental health on RA disease activity in terms of patient-reported outcomes (PROs). Plain Language Summary Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory condition that affects 1% of the global population. RA can cause inflammation and damage to the joints. It can also present with extra-articular manifestations, affecting other major organs in the body. RA patients are more prone to have anxiety, depression and cognitive impairment compared to the general healthy population. Those mental health conditions contribute to less responsiveness to treatment and higher disease activity in RA mainly due to fatigue and bodily pain. Medications used in RA can improve anxiety and depression to a certain extent but not completely. Therefore, it is important to determine the most appropriate tool to monitor mental health well-being and quality of life (QoL) of RA patients in rheumatology outpatient clinics to optimise the care of the RA patients.