key: cord-0970687-0cuoaw9z authors: Mariani, Chiara; Borgonovo, Fabio; Capetti, Amedeo F; Oreni, Letizia; Cossu, Maria Vittoria; Pellicciotta, Martina; Armiento, Luciana; Bocchio, Simona; Dedivitiis, Gianfranco; Lupo, Angelica; Galli, Massimo; Rizzardini, Giuliano title: Persistence of Long-COVID symptoms in a heterogenous prospective cohort date: 2022-01-22 journal: J Infect DOI: 10.1016/j.jinf.2022.01.024 sha: f7062a074619b7977784ce416c4edcb390335c6f doc_id: 970687 cord_uid: 0cuoaw9z nan Dear Editor, we read with interest the article by Xiaoyu Fang and colleagues [1] , showing the results of a multicenter prospective cohort study related to COVID-19 sequelae one year after acute illness, as well as potential risk factors. We present our data collected from May 11, 2020 to September 24, 2021 at the "Luigi Sacco" University Hospital, Milan, where the ARCOVID (Ambulatorio Rivalutazione COVID) outpatients" clinic began to follow "long haulers", periodically controlling the persistence of physical and psychological symptoms, in order to assess their duration and the predictive factors associated with their resolution. Patients aged >18 years with confirmed COVID-19 (by PCR/antibody detection) were either referred by the physicians who had taken care of them in the acute phase or came voluntarily. After signing written informed consent they were enrolled in the AntiCROWN longitudinal study of anti-S1/S2 IgG response and clinical follow-up, approved by the "Comitato Etico Interaziendale Area 1", n. 2020/ST/158. Throughout the first visit patients received a standardized clinical examination, serological sample to detect anti-S1/S2 IgG levels, 6-minutewalk test in case of dyspnea, and, if necessary, blood work and then sometimes were referred to other specialists. Moreover, they were asked about ongoing symptoms. The follow-up continued using questionnaires sent to each patient every 3 month. Researchers have initially approached Long-COVID by phone calls performed 60 days after discharge, which revealed the persistence of at least one symptom in 66-100% of subjects, according to disease severity [3, 4] , with implications of job loss and mental health impact [5] . A review of such short-term evaluations lead to a comprehensive description of the frequency of each Long-COVID symptom [6] . (49.8%) [8] . Our study" peculiarity is that the population is wider, including all grades of the WHO severity scale, and the observation period is longer than 12 months. Biases are the fact that symptoms were reported as present/absent, without severity scales. Specialists have gradually gathered around the project and we hope that more insight can be given in the future. Clinical visits detected sometimes a fluctuating course of the symptoms, leading to depression. The cause of fatigue has not been clarified yet, but it has been compared to post-infectious fatigue. A 6 discrepancy between dyspnea, leading to a significant reduction in exercise endurance, and persistent lung damage is not uncommon. Anosmia and ageusia are so peculiar that pathophysiology is still unclear. Symptoms often evolve into altered smell and taste, which worsens the patients" quality of life. The mechanism underlying the onset of COVID-related amnesia is still debated as the virus has shown some neurotropic and vasculotropic affinity, as well as the ability to stimulate the production of neurotoxic cytokines [9] . What happens after COVID-19 disease cannot be summarily referred to a simple convalescence period in which symptoms gradually but linearly decrease. Post-sequelae one year after hospital discharge among older COVID-19 patients: A multi-center prospective cohort study Severity Index: A predictive score for hospitalized patients Symptom duration and risk factors for delayed return to usual health among outpatients with COVID-19 in a multistate health care systems network -United States Follow-up of adults with noncritical COVID-19 two months after symptom onset Sixty-Day Outcomes Among Patients Hospitalized With COVID-19 TLC Study Group. Symptoms, complications and management of long COVID: a review 6-month consequences of COVID-19 in patients discharged from hospital: a cohort study Twelve-month systemic consequences of COVID-19 in patients discharged from hospital: a prospective cohort study in Wuhan, China Neurological Involvement in COVID-19 and Potential Mechanisms: A Review. Neurocrit Care We acknowledge our patients for participating.