Based on over 470,000 non-hospitalised patients with a history of COVID-19 and closely matched individuals with no history of COVID-19, we found that those with a history of infection cost primary care services on average an additional £2.44 per patient for primary care consultations at least 12 weeks after infection. However, this incremental cost could be as high as £5.72 per patient. The incremental costs were significantly higher for those diagnosed with long COVID (£30.52) and those documented as reporting associated symptoms (£57.56). Most of these additional costs were from GP telephone consultations. We estimate that the national costs for primary care consultations to support people with long COVID in the UK are approximately £23 million but may approach £60 million.
Among those with a history of COVID-19, higher consultation costs were associated with having a diagnosis or reporting symptoms of long COVID, older age, being female, and obesity. While the most affluent socioeconomic quintile had lower costs than those from more deprived socioeconomic groups, there was no clear socioeconomic gradient in incremental costs. By contrast, those from black ethnic groups incurred lower costs than those from white ethnic groups, while there was no difference with other ethnic groups. This highlights a potential health inequality, especially given the poorer outcomes (e.g., more hospital admissions, higher mortality rate) following COVID-19 among individuals from black ethnic minority groups.21, 22
Using data from the CPRD Aurum database, Whittaker et al. (2021) reported that patients with COVID-19 had significantly higher GP consultation rates, which led to an 18% increase in healthcare utilisation post-infection compared to the 12 months prior.6 Furthermore, patients with COVID-19 continued to display higher GP consultation rates even four weeks after infection. We further show that this trend continued beyond 12 weeks after SARS-CoV-2 infection and have estimated associated consultation costs.
Koumpias et al. (2022) assessed the healthcare use and costs of over 250,000 patients with a history of COVID-19 using administrative claims data in the United States from March to September 2020.23 They found that monthly costs of healthcare resource utilisation increased significantly following COVID-19 compared to prior to infection, with additional costs persisting beyond five months, particularly among adults aged older than 45 years. Their study however did not have a contemporary control group and did not delineate between primary and secondary care services.
Calderón-Moreno et al. (2022) investigated the primary care costs associated with COVID-19.24 They assessed 6,286 COVID-19 patients in Aragon, Spanish, estimating an average illness-associated cost of €729.79 per patient. The costing approach was unclear and there are difficulties in comparing healthcare costs between countries, but the study highlighted the significant economic burden of the illness.24 The authors noted the complications arising from COVID-19, such as respiratory, cardiovascular, and haematological disorders, caused further cost increases, but they did not specifically comment on the costs associated with long COVID.
There is also broader literature on the impact of COVID-19 on the utilisation of primary care resources. For many patients, especially those with less severe illnesses, the pandemic led to a reduction in overall healthcare use, but an increase in the number of non-face-to-face consultations.25 We similarly found that the increased cost of primary consultations associated with long COVID were driven by an increase in telephone consultations.
A strength of the study was that the costs associated with long COVID could be isolated by implementing an incremental cost approach using a highly matched comparison group with no prior history of suspected or confirmed COVID-19. The comprehensive matching algorithm, accounting for many relevant variables, successfully balanced demographics, and clinical characteristics between the exposed and unexposed cohorts. This was fundamental to the inferences being made, as except from unobservable factors, the only key difference between the cohorts were the record of SARS-CoV-2 infection.26 Another strength was the large sample size (i.e., 944,346 patients), which boosted statistical power for our analyses and ensured representative results for the UK population.13, 27
A key limitation was the lack of long COVID diagnosis in primary care records.17 Our study incorporated costs for consultations that occurred at least 12 weeks after confirmation of SARS-CoV-2 infection (or matched time point for the unexposed cohort). We inferred that any differences in consultation costs beyond this time point were likely to be attributable to long COVID, given that both cohorts had similar characteristics except for SARS-CoV-2 infection.
The duration of consultations is not well recorded, limiting cost calculations. We used PSSRU’s 2021 Unit costs for primary care consultations with standard durations, but factors like clinician experience and patient characteristics might alter actual durations and consultation costs.28 Furthermore, when estimating the national costs from consultations associated with long COVID, we assumed that incremental costs would remain constant over the course of the pandemic, which may not necessarily be true as access to primary changed during this period.
We used propensity score matching to reduce confounding, but residual confounding may still affect differences in consultation rates between the exposed and unexposed cohorts. However, we anticipate that residual confounding would be limited in our results, given the wide range of demographic and clinical covariates considered.
Another limitation is the potential misclassification of individuals in the unexposed cohort due to limited community testing during the pandemic’s first wave.29 Some members of the unexposed cohort may have had COVID-19 but not been formally tested. We attempted to limit this by excluding patients from the unexposed cohort if they had a record of either suspected or confirmed COVID-19, even in the absence of any confirmatory testing. However, misclassification bias may still be present, leading to an underestimation of the true incremental cost of primary care consultations associated with long COVID.
Our analysis indicates substantial primary care costs to support non-hospitalised patients with long COVID, even when only considering consultation costs. This is at a time of exceptional pressure on health services, including primary care in the UK and worldwide. UK primary care may require £20-£60 million for primary care consultations in patients with long COVID, mostly for remote GP consultations, with similar costs in comparable settings. It should be noted that some non-hospitalised patients with COVID-19 might require secondary care referral, causing further costs not considered here. Overall, significant investment globally is needed for primary care services to address the complex care needs and ongoing symptoms of non-hospitalised patients. Training allied healthcare professionals to support this care and implementing guidelines for long COVID diagnosis and care,30 could potentially reduce these costs.
Our analysis also indicates significant additional primary care costs for patients with a history of COVID-19 and reporting relevant symptoms, without a formal long COVID diagnosis. Furthermore, certain population subgroups amongst those with a history of COVID-19 can incur increased costs, such as the elderly, females, and those with obesity. Additionally, those from black ethnic groups may be underusing primary care services for long COVID symptoms, representing a potential health inequity. These factors should be considered by health service commissioners, managers and providers when designing and resourcing long COVID services in primary care as well as planning for similar future pandemic viruses.
Our study provides a foundation in methods and cost estimates for future cost analyses and economic evaluations on long COVID, with lessons for future pandemic planning, including the need for careful planning for the longer-term impacts of pandemics. Future research should focus on updating this analysis to capture longer-term patient data and costs, evaluate the impact of long COVID on prescription drug costs, assess secondary care costs, assess out-of-pocket costs, and explore methods to better capture costs specifically attributable to long COVID.