Association of body mass index on long COVID: Predisposing factors, symptom severity, and functional status in a Spanish cohort of COVID-19 patients

Problem considered: Long COVID (LC) refers to a collection of symptoms that persist or emerge after an acute SARS-CoV-2 infection.It is a complex, multi-system condition that significantly affects quality of life.While obesity is a well-known risk factor for severe acute COVID-19, its role in the development and severity of LC remains underexplored.This study aimed to investigate the association between pre-infection Body Mass Index (BMI) and LC, as well as its impact on symptom type, their severity, and functional status.Methods: This case-control study included 315 participants with prior confirmed SARS-CoV-2 infection.Participants were classified as LC cases or controls based on WHO criteria.Data was collected via an online self-reported survey.BMI prior to COVID-19 was categorized as underweight, normal weight, or overweight/obesity.Functional impairment was assessed using the Post-COVID Functional Status (PCFS) scale, models were used to examine associations, adjusting for potential confounders.Results: Participants with overweight/obesity were associated with an increased developing LC (OR 2.85;) and experiencing moderate to severe functional limitations (OR 2.65; 95% CI 1.32-5.31),compared to those with normal weight.Obesity was also associated with a higher likelihood of developing specific LC symptoms, including asthenia, dyspnea, headache, brain fog, anxiety, and myalgia.Underweight status showed less consistent associations.Conclusion: Pre-infection obesity is an independent factor for the development LC and its functional consequences.Individuals with obesity may be considered a high-risk group and prioritized in public health strategies.