Long-term effects on physical and mental health and work ability after COVID-19 versus other upper respiratory infections

Overview

This study compared long-term health outcomes and work capacity in individuals testing positive for COVID-19 during the initial pandemic wave (March-May 2020) versus those with similar acute respiratory symptoms who tested negative. The investigation addressed whether COVID-19 infection produced distinct long-term sequelae relative to other upper respiratory infections presenting with comparable clinical presentation. Two-year follow-up assessment employed validated instruments measuring self-rated physical and mental health status alongside work-related functional capacity.

Methods and approach

Participants comprised individuals tested for COVID-19 at a Danish hospital during the first pandemic wave with substantial respiratory infection symptoms. Approximately two years post-testing, participants received questionnaires incorporating the SF-12 instrument for self-assessed health status (physical and mental components) and the WORQ instrument for work-related functional capacity evaluation. PCR test results from 2020 and self-reported COVID status from spring 2022 questionnaires established infection status. Comparative analysis between PCR-positive and PCR-negative groups was conducted with adjustment for relevant confounding variables. Total respondents numbered 463 with a response rate of 17 percent.

Results

Comparison between COVID-positive and COVID-negative groups revealed no statistically significant differences in physical health component scores (PCS) or work-related functional ability (WORQ) following adjustment for confounders. Mental health component scores (MCS) demonstrated a small but statistically significant difference, with non-COVID-positive participants showing slightly elevated scores compared to COVID-positive participants (49.3 versus 47.5, p<0.009) when adjusted for working status. Occupationally active participants demonstrated higher rates of COVID-19 infection compared to non-working participants.

Implications

The findings indicate substantial overlap in long-term health sequelae between COVID-19 and other acute upper respiratory infections with similar initial clinical presentations. The absence of clinically meaningful differences in physical health status and work capacity recovery between groups suggests that documented long-term effects may reflect general consequences of acute respiratory infection severity rather than pathophysiologic specificity to SARS-CoV-2 infection. These results support redirecting clinical focus toward commonalities in post-infectious syndrome management across etiologies. Comprehensive rehabilitation interventions targeting symptom persistence and functional restoration warrant implementation independent of specific viral etiology, as outcome trajectories appear comparable between diagnostic groups.