Fibromyalgia, 'fibromyalgianess', and fatigue are common six months following COVID-19 infection

ABSTRACT

Purpose: To estimate the prevalence of fibromyalgia (FM), 'fibromyalgianess' and fatigue six months following COVID-19 infection. Method: Consecutive consenting patients were recruited from a post-COVID-19 infection clinic. The following self-reported questionnaires were completed 6 months following COVID-19 infection widespread pain index (WPI), symptom severity scale (SSS), 10-point visual analogue scale to assess fatigue severity (VAS-F) and 9-item, 7-point fatigue severity scale (FSS). The sum of SSS and WPI scores was used to calculate a polysymptomatic distress (PSD) score. FM was defined as per the 2016 revisions to the 2010/2011 American College of Rheumatology (ACR) criteria, and 'fibromyalgianess' was defined using polysymptomatic distress scale recognising the continuum of FM symptoms. Results: Of 25 study participants, the median age was 59 years (range 21-80), nine were female (36%) and 15 had been admitted to hospital for Covid-related complications (60%). Six months following infection, five met WPI and SSS criteria for fibromyalgia and three others had PSD scores >12 suggestive of severe symptoms;all were under 60 years. Problematic fatigue (mean FSS > 4) occurred in nine patients (36%) and although not statistically significant it was seen more frequently in females compared with males (56% vs 25%;95% CI -9% to 71%) and in those <60 years (46% vs 25%;CI -16% to 58%). Mean (± SD) FSS was 29.7 (± 15.0) and VAS-F was 6.0 (± 2.9). Compared to male patients, female patients demonstrated statistically significant higher mean WPI (8.0 vs 2.0), SSS (7.0 vs 2.1) and PSD (15.0 vs 4.1). Conclusion: Six months following COVID-19 infection, fibromyalgia, 'fibromyalgianess' and fatigue are common, with higher frequency in females and younger patients. This pattern parallels conventional fibromyalgia cohorts and may favour targeted service delivery. Further studies are needed to determine whether symptoms persist long-term.