COVID-19-associated Telogen Effluvium After Hospital Discharge: A Prospective Cohort Study.

Introduction Telogen effluvium (TE) is a common sequela of SARS-CoV-2 infection. Existing studies are highly heterogeneous. We aimed to assess the prevalence of TE in a cohort of patients with severe disease hospitalized for acute COVID-19. Methods This prospective cohort study was conducted at the University Clinic of Dermatology, part of the COVID-19 University Hospital Network throughout the pandemic. The acute phase data were extracted from electronic hospital records. Details about hair loss were obtained at two follow-up points, 3 and 6 months after hospital discharge, using telephone interviews. Results A total of 77 patients were successfully followed up, and 40 (48.8%) were male. The mean age was 55.91, SD=10,588. Overall, 68.8% of patients reported TE. Among these, 52.8% reported early onset, and 50.9% reported moderate hair loss. 11 (20.7%) reported complete hair regrowth within three months, and an additional 32 (60.3%) reported complete regrowth within six months. 4 (7.5%) patients have chronic TE. Female sex (p<0.0001), anemia (p=0.019), hypoproteinemia (p=0.037), and severe pneumonia (p=0.004) were associated with TE. Age, fever, SpO2, CRP levels, in-hospital complications, and raised D-dimers were not associated with TE. Discussion Our study confirmed a high prevalence of COVID-19-associated TE in hospitalized patients. Anemia and hypoalbuminemia were associated with TE, shedding new light on the possible pathogenesis. COVID-19-associated TE occurs earlier than classic TE and has a good prognosis in most patients. However, chronic ТЕ was reported by 7.5%. Even a small incidence of long-term sequelae during a pandemic could have substantial health consequences.