Long COVID Symptoms in Non-Hospitalised Patients: A Retrospective Study.

INTRODUCTION

The COVID-19 pandemic has presented numerous challenges to healthcare systems. As the number of affected individuals continues to rise, it is crucial to find preventive, diagnostic, and therapeutic approaches. This study aims to describe different COVID-19 sequelae within a Primary Health Care population.

METHODS

A retrospective cohort study was conducted in adults diagnosed with COVID-19 from March 2020 to April 2022, excluding pregnant women, minors, nursing home residents, hospitalizations, and deaths. Data was gathered from surveillance records on the Trace COVID-19® platform, a pre-set original questionnaire (which included the Portuguese version of the World Health Organization's Quality of Life Assessment Instrument), and, if needed, patient electronic health records. Information on sociodemographic and clinical characteristics of acute COVID-19 was collected along with long COVID symptoms.

RESULTS

This study included 284 patients, aged 19 to 99 years old. The five most prevalent acute COVID-19 symptoms were fever (50.0%), tiredness (48.2%), myalgias (44.7%), dry cough (37.7%) and odynophagia (36.3%). Symptoms related to the neurological system (23.2%) and tiredness (22.9%) were the most prevalent in long COVID symptoms. Acute tiredness and arthralgia were associated with all long COVID outcomes. The associations between acute COVID-19 symptoms with long COVID outcomes were stronger for anosmia [OR = 5.07, 95% confidence interval (CI) 2.49 - 10.36, p < 0.001] on a neurological chapter, acute tiredness for long lasting tiredness (OR = 4.07, 95% CI 2.07 - 8.02, p = 0.041), fatigue for muscles and/or bones chapter (OR = 7.55, 95% CI 3.06 - 18.66, p < 0.001), tiredness on an endocrine/hormonal chapter (OR = 6.54, 95% CI 2.37 - 18.04, p < 0.001), dyspnea for respiratory symptoms (OR = 5.67, 95% CI 1.92 - 16.74, p = 0.002) and fever for stomach or intestine symptoms (OR = 8.06, 95% CI 2.55 - 25.47, p < 0.001). Almost all quality of life dimensions were negatively associated with the number of long COVID symptoms.

CONCLUSION

A higher number of acute symptoms, as well as the presence of specific COVID-19 symptoms were associated with reported symptoms ≥ 12 weeks after infection. In the studied population, an increased number of symptoms in both acute and long COVID had a significant negative impact on the perception of overall quality of life. The identification of these relationships could provide a new perspective for post-COVID care.