The prevalence and impact of Long COVID in the primary care population

4. Patient reported health outcomes of Long COVID

4.1. Health and social outcomes are worse among patients with Long COVID

Compared to patients without Long COVID, those with Long COVID reported higher rates of severe fatigue (20% versus 10%). Those with Long COVID also reported higher rates of being on sick leave or unemployed and not looking for work (13% versus 11%), although the difference was not significant (see Figure 6).

Patients with Long COVID without another chronic condition reported lower rates of sick leave (3%) than those with 1‑2 chronic conditions (9%) or more than 2 chronic conditions (26%) (see Table A.2). However, among patients who had the same number of chronic conditions, there was no difference in rates of sick leave between patients with Long COVID and those without Long COVID (see Table A.2). This may indicate that patients are more likely to be unemployed and not looking for work or on sick leave due to already living with chronic conditions, rather than because of Long COVID.

Figure 6. Patients with Long COVID report significantly higher rates of severe fatigue

Source: OECD PaRIS 2024 Database.

Patients with Long COVID had significantly lower average (42 versus 48) self-rated physical health T-scores and a slightly lower average (46 versus 48) self-rated mental health T-scores, compared to patients without Long COVID (see Figure 7). The range and cut-off for T-scores are defined and explained in the notes of Figure 7.

A significantly lower percentage of patients with Long COVID (75%) self-rated their mental health as “good” compared to those without Long COVID (81%). The average physical health T-score for patients with Long COVID is classified as borderline “fair”, as opposed to “good” for those without Long COVID. A significantly lower percentage of patients with Long COVID (60%) self-rated their physical health as “good” compared to those without Long COVID (70%).

Figure 7. Distribution of self-rated physical and mental health T-scores by Long COVID status

Notes: PROMIS® Scale v1.2 – Global Health component for mental health is a T-score metric with a range of 21‑68, and a good-fair cutoff of 40 (orange dashed line), higher values represent better mental health. For physical health the T-score metric has a range of 16‑68, and a good-fair cutoff of 42 (orange dashed line). The boxplot displays the median, and upper and lower quartiles for the T-score.

Source: OECD PaRIS 2024 Database.

4.2. Severe fatigue is a major symptom of Long COVID, although this does not appear to affect workforce participation

Compared to those without Long COVID, patients with Long COVID reported significantly higher rates of severe fatigue and worse physical and mental health, regardless of the number of chronic conditions they have. A household survey of American participants in 2021/22 reported higher unemployment in patients living with Long COVID (12.3%) compared to those without (8.7%), and those living with Long COVID were 29% less likely to be working fulltime (Perlis et al., 2023[10]). However, analysis of PaRIS data shows that Long COVID does not result in significantly higher rates of reported unemployment or sick leave among primary care patients in the working age group, once number of chronic conditions are accounted for (see Table A.2). This suggests that while the impact of Long COVID on patients’ self-reported health is considerable, their participation in the workforce may be less impacted. This analysis was restricted to participants of working age, who did not report already being retired, and does not account for potential increases in presenteeism (where an employee attends work despite a medical illness that will prevent them from fully functioning) or reduced productivity or ability to work fulltime (Widera, Chang and Chen, 2010[20]), as a result of Long COVID in OECD economies.