Self-reported physical activity and fatigue and its associations to anxiety and depression in adult patients with idiopathic inflammatory myopathies: a MIHRA psychological impact and MIHRA exercise and rehabilitation scientific working groups collaboration.

Objectives: To evaluate self-reported physical activity (PA) levels as well as the relationship between PA, anxiety, depression, quality of life, pain, fatigue, disease activity, and organ damage in patients with idiopathic inflammatory myopathies (IIM).

Methods: All adult patients registered at the rheumatology clinic at Karolinska University Hospital in Stockholm, Sweden (2019-2022) were eligible to participate. Questionnaires measuring anxiety, depression (HADS), and PA (IPAQ) were provided during yearly check-up or by mail, due to reduced in-person visits amid the Covid-19 pandemic. Additional data was obtained from the Swedish Rheumatology Quality Registry.

Results: Of 488 invited patients, 336 agreed to participate, and 246 completed the questionnaires. Median (range) age was 64 (20-88) years, median disease duration five (0.3-61) years and two-thirds were women. Notably, 82% reported moderate/high level of PA. Probable anxiety and depression were experienced by 25% and 14%, respectively. The findings indicated a potential protective effect of PA against depression (OR 0.23, CI 0.06-0.95). Conversely, patients who were physically inactive had poorer mental health, reduced muscle function, increased organ damage, and fatigue. Fatigue demonstrated a progressive link to heightened risks of anxiety (2%, 2-4%) or depression (3%, 1-6%).

Conclusions: Most patients with IIM reported being physically active. The study highlights the potential influence of PA on mental health and its role in mitigating risks associated with depression and fatigue among IIM-patients. It also underscores the importance of patient-reported outcomes, and their role in understanding and improving healthcare interventions. Further research is needed to uncover causes and confirm these associations.