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. 2025 Apr 28;58(8):1469–1476. doi: 10.1002/eat.24443

Trends in the Observed Versus Expected Incidence of Eating Disorders Before, During, and After the COVID−19 Pandemic: A National Patient Registry Study

Deborah Lynn Reas 1,✉, Gunnar Rø 2, Øyvind Rø 1,3
PMCID: PMC12336761  PMID: 40289882

ABSTRACT

Objective

This study investigated post‐pandemic trends in the incidence of eating disorders (EDs) by comparing the annual observed incidence from January 1st, 2020, to December 31st, 2023, to the expected incidence based on pre‐pandemic trends (2010–2019).

Method

Primary and auxiliary ICD‐10 diagnoses of new‐onset ED cases were retrieved from the Norwegian Patient Registry which is a national register covering all specialized healthcare services in Norway. Incidence rates (IRs) per 100,000 were stratified by age, sex, and diagnosis: anorexia nervosa (AN; F50.0 + 50.1), bulimia nervosa (BN; F50.2 + 50.3), and other EDs (F50.4–50.9). To assess the impact of the COVID‐19 pandemic, linear regression models were used to estimate the annual excess incidence of EDs between 2020 and 2023.

Results

IRs for EDs peaked in 2021, with the overall rate for females being 45.5% higher than expected in 2021 before declining to an excess of 19.4% in 2023. The highest IRs were observed in females aged 15–19, followed by females aged 10–14 and 20–24 years. In 2021, the IR for females aged 15–19 was 64.7% higher than expected before declining sharply to 10.9% in 2023, whereas IRs for ages 10–14 and 20–24 remained approximately 30% higher than expected. Increases were particularly pronounced for AN, while the incidence of BN remained comparatively low, tracking with observed pre‐pandemic declines.

Conclusions

New‐onset ED cases peaked in 2021, then declined in 2022 and 2023, despite remaining higher than expected based on 10 years of pre‐pandemic data. Future research should continue to monitor trends in incidence, and community‐based studies are necessary for replication.

Keywords: anorexia nervosa, bulimia nervosa, COVID‐19, eating disorders, epidemiology, incidence

1.

Summary.

  • This study explored pre‐ and post‐pandemic trends in healthcare‐detected incidence using a national patient register encompassing all specialist care in Norway between 2010 and 2023.

  • The incidence of EDs peaked in 2021, with the observed rate of any ED among females rising 45.5% above expected levels before declining to a 19.4% excess by 2023.

  • Data show a lingering and disproportionate impact of the COVID‐19 pandemic on the risk of developing an ED, particularly among younger persons and individuals affected by AN.

2. Introduction

The COVID‐19 pandemic has been widely recognized as a catalyst for a global mental health crisis, marked by rising rates of mental health disorders (Santomauro et al. 2021), including a dramatic increase in the risk and burden of eating disorders (EDs) (Zipfel et al. 2022). Research conducted during the pandemic's peak years revealed a surge in referrals, hospital admissions, and emergency department visits related to eating disorders worldwide (Devoe et al. 2023; McLean et al. 2022; Meier et al. 2022). A “perfect storm” of pandemic‐related factors converged to heighten risk (Nicholls 2023), including disrupted routines, limited access to resources and support, social isolation, stress, and adverse effects of social media (Devoe et al. 2023; Rodgers et al. 2020; Schlissel et al. 2023). Additionally, population‐level shifts in food consumption (Ammar et al. 2020) and increased food insecurity (Williams et al. 2024) exacerbated risk.

The surge in ED‐related admissions and referrals during the initial COVID‐19 pandemic years has been attributed to symptom deterioration (Branley‐Bell and Talbot 2020; Haghshomar et al. 2022; Vavassori and Donzelli 2024) and relapse (Termorshuizen et al. 2020), as well as the development of new‐onset, or incident, EDs (Davies et al. 2023). Incidence refers to the occurrence of new cases and is less commonly reported in the ED field than prevalence data (for a review of prevalence studies, see Lindvall Dahlgren and Wisting 2016; Silén and Keski‐Rahkonen 2022). A Canadian network of pediatric tertiary‐care hospitals reported an increase of over 60% in new‐onset cases of anorexia nervosa (AN) and atypical AN (AAN) among youth aged 8–19 during the first wave of COVID‐19 (March 1st—November 30th, 2020), increasing from a monthly pre‐pandemic mean of 24.5 to 40.6 cases (Agostino et al. 2021). An analysis of electronic health records of 5.2 million people under the age of 30, primarily from the USA, reported an overall excess in incidence of 15.3% in 2020 compared to 2019; the highest risk was observed among females aged 10–19 diagnosed with AN (Taquet et al. 2021). A UK investigation of primary care records in the UK from March 1, 2020, to March 31, 2022, found the observed incidence of EDs was 33.1% higher than predicted among females aged 10–24 years when compared to antecedent trends (Trafford et al. 2023). Lastly, a Norwegian study assessed changes in the percentage of children aged 6–16 diagnosed with EDs since March 2020 in a pandemic cohort (2019–2021) and after March 2018 in a pre‐pandemic cohort (2017–2019). Most notably, the percentage of girls aged 13–16 in specialist care for EDs increased from 0.49% to 1.51% in the pandemic cohort, representing a relative increase of 95.96% compared to the pre‐pandemic cohort (Suren et al. 2022). Collectively, these studies suggest the COVID‐19 pandemic had a dramatic and disproportionate impact on ED‐related mental health in the population, particularly affecting younger individuals, females, and those at risk for developing AN (Laskowski et al. 2024; Linardon et al. 2022).

The World Health Organization declared COVID‐19 a public health emergency of international concern in January 2020 and ended the global emergency status in May 2023. However, it remains unclear whether the upward trends in new‐onset cases of EDs during the height of the COVID‐19 pandemic have continued, or if rates have begun to stabilize or decline. To our knowledge, only two studies have yet investigated trends in incidence beyond 2022, and findings are mixed. First, a Danish register‐based study examined the cumulative excess incidence of broadly‐defined AN and BN among individuals aged 6 to24 years through December 2023 (Sonne et al. 2024). The overall average IR in the pre‐pandemic period (January 2015 to February 2020) was 94/100,000, increasing to 116/100,000 during the pandemic (March 2020 to January 2022), thereafter decreasing to 95/100,000 following the pandemic (February 2022 to December 2023). Findings indicated a return to pre‐pandemic levels for all age groups except for females aged 20–24 years, who exceeded the expected rates of any ED by 32% (Sonne et al. 2024). Second, hospital admissions data from Germany showed that AN and AAN decreased significantly during the first six months of 2023 except for children aged 9 to 14 years. Admissions for this age group remained steady and significantly higher than pre‐COVID levels. In fact, the number of admissions for girls aged 9 to 14 was 40% higher during the first half of 2023 compared to the six months prior to the pandemic (Herpertz‐Dahlmann et al. 2024).

While the initial studies from Denmark and Germany have shown promising declines (Herpertz‐Dahlmann et al. 2024; Sonne et al. 2024), they also reveal a lingering impact for a significant number of individuals. Additional research is needed to determine whether the effects of the pandemic on EDs are temporary or have persisted beyond the peak years of the COVID‐19 era and, if so, who remains most affected. Any investigation of post‐pandemic trends in incidence should ideally be viewed within the historical context of pre‐pandemic trends and stratified by age, sex, and type of ED diagnosis. Such an approach may provide a more nuanced understanding of the potentially disproportionate immediate—and longer‐term—impacts of the COVID‐19 pandemic. This is especially important because epidemiological research prior to the pandemic had already documented increasing rates of AN and atypical AN among young females, while rates of bulimia nervosa (BN) declined (Reas and Ro 2018; van Eeden et al. 2021). For instance, a study by van Eeden et al. (2023) found increasing rates of AN among girls aged 10–14 treated in primary care over the past four decades from 1985 to 2019, whereas rates remained stable for other age groups and BN declined since the 2010s.

The aim of this study was to investigate temporal trends in the incidence of EDs by calculating annual incidence rates (IRs) since 2010 and the yearly excess incidence from January 1, 2020, to December 31, 2023, based on a decade's worth of pre‐pandemic data. By leveraging a national patient registry with nearly 100% coverage of all outpatient and inpatient specialized care, and stratifying by age, sex, and diagnostic category, our aim was to contribute to the existing body of evidence concerning the immediate and longer‐term effects of the COVID‐19 pandemic on the incidence of EDs.

3. Method

Age‐ and sex‐stratified IRs per 100,000 were calculated using mid‐year population data obtained from annual census data from Statistics Norway (SSB 2016). The total entity encompassed all residents of Norway aged 10–59 years. Incident cases were defined as the first‐time (i.e., index) registration of a primary or auxiliary diagnosis of an ED (ICD‐10 F50.0–50.9) (WHO 1992) in the Norwegian Patient Registry between January 1st, 2010, and December 31st, 2023. The NPR is a national health register covering all specialist healthcare since its inception in 2008. Specialist care includes all inpatient admissions, day treatment, and outpatient somatic or mental health‐related visits, including private practitioners or private clinics with government contracts. The database is currently managed by the Norwegian Institute of Public Health (FHI) (Bakken et al. 2020). Financial reimbursement for specialized healthcare services is linked to NPR registration, which ensures nearly 100% coverage. To minimize the risk of including prevalent (i.e., non‐incident) cases such as relapses or readmissions, a 48‐month lag period was applied by excluding all individuals with any ED diagnosis registered in 2008 or 2009. From 2010 onwards, a maximum of one registration per diagnostic entity per individual was allowed, but similar to prior research (Reas and Ro 2018), diagnoses were not mutually exclusive, meaning that individuals could contribute to the IR of AN at one time point and contribute to the IR of BN at another. Written consent was not required for ordering anonymous register data, nor was approval necessary from the Regional Committee for Medical and Health Research Ethics (REK) in accordance with applicable laws and regulations in Norway.

4. Statistical Analysis

IRs (95% CI) were calculated per 100,000 stratified by sex, diagnostic grouping (AN; ICD F50.0 + 50.1), bulimia nervosa (BN; F50.2 + 50.3), and other EDs (F50.4–50.9) and age group (10–14, 15–19, 20–29, 30–39, 40–49, and 50–59 years). To quantify the effect of the pandemic on incidence of EDs, we calculated excess incidence ∆t, per year from 2020 to 2023 as defined by

∆t=Yt−Et,

Where Yt is the observed incidence and Et is the expected incidence in year t. We used linear regression models to estimate the expected incidence during the pandemic by fitting them to the observed pre‐pandemic IRs from 2010 to 2019. The confidence intervals for excess incidence were determined by the prediction intervals for the expected IR. The percentage difference, or percent excess, was calculated as the ratio difference between the excess and the expected IR. We allowed for the possibility of a change point in trends between 2010 to 2019 using the segmented R‐package (v2.1–3) (Muggeo 2003), but adding change points only increased the Aiken Information Criterion (AIC) (Burnham and Anderson 2002) indicating poorer model fit hence no change points were needed. All analyses were performed using R Statistical Software (v4.42; R Core Team 2023).

5. Results

A mean of 3,443,433 individuals comprised the background population annually during the study period. A total of 42,720 individuals were diagnosed with an ED, of which 3636 (8.5%) were males. Figure 1 shows the annual age‐stratified observed total incidence for any ED (ICD‐10 F50.0–50.9) among females between 2010 and 2023. The peak incidence year was 2021, except for women aged 40–49 who showed a slight peak in 2020 and in 2023, and women aged 50–59 who showed no discernable peak in incidence. The highest observed IR was recorded for females aged 15–19 years in 2021 (860.3/100,000), followed by females aged 20–24 (468.2/100,000), 25–29 years (285.4/100,000), 10–14 years (249.3/100,000), and 30–39 years (143.2/100,000). Total IRs for any ED among males aged 10–59 were comparatively low, increasing from 11.6 to 18.6/100,000 between 2010 and 2020, thereafter remaining stable throughout the pandemic (18.4, 18.7, and 18.3 per 100,000 in 2021, 2022, 2023, respectively; see Figure S1). Figure 2 shows the annual observed IRs stratified by diagnostic group for females between 2010 and 2023. The highest IR was recorded for AN in 2021 at 107.7 per 100,000, before falling to 83.7/100,000 in 2023. Similarly, other EDs (F50.4–50.9) increased to an IR of 101.6/100,000 in 2021, then declined to 83.6/100,000 in 2023. However, the IR for BN continued a general downward trend, decreasing to 34.9/100,000 in 2023.

FIGURE 1.

FIGURE 1

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Annual age‐stratified observed incidence in eating disorders per 100,000 for females aged 10–59 years from 2010 to 2023. The graph depicts the observed annual age‐stratified observed incidence rates (IRs) per 100,000 from 2010 to 2023 for females and included all ICD‐10 diagnoses: Anorexia nervosa (AN; F50.0 + 50.1), bulimia nervosa (BN; F50.2 + 50.3), and other EDs (F50.4–50.9).

FIGURE 2.

FIGURE 2

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Annual observed incidence in eating disorders per 100,000 for females aged 10–59 years stratified by diagnostic group from 2010 to 2023. The graph shows the annual total incidence rates (IRs) per 100,000 in EDs for all females aged 10–59 years stratified by ICD‐10 diagnostic group: Anorexia nervosa (AN; F50.0 + 50.1), bulimia nervosa (BN; F50.2 + 50.3), and other EDs (F50.4–50.9).

5.1. Excess Incidence (95% CI) between 2020 and 2023

As shown in Table 1, the total excess incidence for any ED in females in 2020 was 26.2 cases (95% CI: 9.1–43.2), increasing to 71.1 (95% CI: 53.2–88.9) in 2021, before falling to 30.2 (95% CI:10.4–50.5) in 2023. This indicates that the IRs among females were 16.7% higher than expected in 2020, 45.5% higher in 2021, and 19.4% higher in 2023. For males, the number of excess cases for any ED remained comparatively low, decreasing from 2.6 cases per 100,000 in 2020 to 1.0 case in 2023, leveling off to a rate that was 5.6% higher than expected.

TABLE 1.

Excess incidence (95% CI) per 100,000 and average percent excess in 2020, 2021, 2022, and 2023 based on observed pre‐pandemic trends (2010–2019).

2020 2021 2022 2023
Diagnosis # excess cases % excess # excess cases % excess # excess cases % excess # excess cases % excess
Female, yrs
10–14 Any ED 54.3 (40.7–67.9) 36.5% 95.3 (81–109.5) 60.2% 68.6 (53.6–83.6) 40.9% 53.9 (38.1–69.6) 30.5%
15–19 Any ED 78 (−47.3–203.4) 15.3% 337.5 (206.1–468.9) 64.7% 189.2 (51.1–327.4) 35.6% 59.3 (−86.2–204.8) 10.9%
20–24 Any ED 24.6 (−41.1–90.3) 8.0% 162.3 (93.5–231.2) 54.4% 98.1 (25.7–170.6) 33.8% 85.9 (9.6–162.1) 30.5%
25–29 Any ED 49.3 (17.3–81.4) 25.0% 90.7 (57.1–124.2) 47.7% 57.4 (22.1–92.7) 31.4% 59.3 (22.1–96.5) 33.8%
30–39 Any ED 15.0 (−9.0–39.1) 12.4% 27.4 (2.2–52.6) 22.9% 18.1 (−8.4–44.6) 15.2% 22.9 (−5.0–50.8) 19.3%
40–49 Any ED 21.7 (8.6–34.8) 42.3% 15.9 (2.2–29.7) 32.7% 11 (−3.4–25.5) 23.9% 27.8 (12.6–43.0) 64.2%
50–59 Any ED 3.5 (−8.5–15.6) 9.6% 0.0 (−12.7–12.6) 0% −2.6 (−15.9–10.7) −6.6% −4.5 (−18.5–9.5) −11.3%
Total (10–59 years) Any ED 26.2 (9.1–43.2) 16.7% 71.1 (53.2–88.9) 45.5% 40.9 (22.2–59.7) 26.2% 30.2 (10.4–50.0) 19.4%
Total (10–59 years) AN 15.0 (5.2–24.7) 21.9% 39.4 (29.1–49.6) 56.9% 21.1 (10.4–31.9) 30.2% 14.9 (3.5–26.2) 21.0%
Total (10–59 years) BN 3.3 (−5.2–11.7) 8.8% 11.2 (2.3–20.1) 32.0% 4.1 (−5.2–13.5) 12.5% 4.6 (−5.2–14.4) 14.7%
Total (10–59 years) Other ED 10.7 (−0.2–21.6) 14.8% 28.9 (17.5–40.4) 39.4% 17.1 (5.1–29.1) 22.9% 9.9 (−2.7–22.6) 13.2%
Male
Total (10–59 years) Any ED 2.6 (0.1–5.2) 16.4% 1.9 (−0.7–4.6) 11.6% 1.8 (−1.0–4.6) 10.4% 1.0 (−2.0–3.9) 5.6%
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Note: CI, confidence interval; AN, anorexia nervosa (ICD‐10 F50.0 + 50.1); BN, bulimia nervosa (ICD‐10 F50.2 + 50.3) and other ED, (ICD‐10 F50.4–50‐9). Excess incidence was calculated as the difference between the observed versus expected incidence per 100,000 person‐years. Average % excess was calculated by dividing the excess incidence by the expected rate and multiplying by 100 to convert it to a percentage. Expected incidence in 2020–2023 was predicted using observed values during the pre‐pandemic study period (2010–2019).

When stratified by age, females aged 15–19 had the highest excess in incidence of 337.5 cases in 2021 (95% CI: 206.1–468.9), which was 64.7% higher than expected. This declined to 59.3 cases by 2023 (95% CI: −86.2 to 204.8), falling to a rate 10.9% higher than expected. Women aged 20–24 had an excess in incidence of 162.3 cases in 2021 (95% CI: 93.5–231.2), which was 54.4% higher than expected, but by 2023, the incidence had decreased to a 30.5% higher‐than‐expected rate. Similarly, the incidence for girls aged 10–14 in 2021 was 60.2% higher than expected, before declining to a 30.5% higher‐than‐expected rate. Compared to younger age groups, women aged 30–39 and 40–49 demonstrated less variability and a lower excess number of cases throughout the pandemic. No discernible excess in incidence was observed among women aged 50–59 in 2021; in fact, the percentage difference between observed and expected cases was negative in 2022 and 2023, meaning the IR for women aged 50–59 was lower than expected during those years.

When stratified by diagnosis, the excess percentage incidence was pronounced for AN, with a 56.9% higher‐than‐expected rate in 2021, thereafter declining to 21.0%. Percentage excesses for BN and other EDs in 2021 were 32.0% and 39.4%, respectively, thereafter declining to rates that were 14.7% and 13.2% higher than expected. The excess number of cases for BN was generally low, increasing to 11.2 in 2021, thereafter declining to 4.6 cases per 100,000 in 2023. Figures S2 and S3 present additional graphical representations of the excess incidence between 2020 and 2023 by plotting the observed versus predicted values of any ED stratified by age and diagnosis.

6. Discussion

This population‐based registry study investigated annual trends in the healthcare‐detected incidence of EDs by comparing the observed incidence from January 2020 to January 2024 versus the expected incidence based on antecedent pre‐pandemic trends from 2010 to 2019. Our investigation represents a unique contribution by extending a very limited pool of evidence regarding temporal trends in the incidence of ED following the COVID‐19 pandemic, to address the important issue of whether pandemic‐related increases have since stabilized or declined. Three main findings are important to highlight. First, our findings concur with the preponderance of evidence highlighting the devastating impact of the COVID‐19 pandemic on the risk and burden of ED‐related mental health (Madigan et al. 2025). By calculating annual incidence rates, our data show that 2021 was the peak year for new‐onset ED; the total excess incidence for females was 45.5% higher than expected. Second, although a reversal has occurred, the data offer a cautious outlook, with persistently higher‐than‐expected rates through 2023. Specifically, the rate of incident cases for any ED diagnosed within specialized care in Norway remained 19.4% higher than expected almost 2 years since the final pandemic‐related restrictions were lifted.

Third, findings highlight the disproportionate impact—and disproportionate lingering impact—of the COVID‐19 pandemic on the risk and burden of EDs for younger females, particularly those affected by AN. Individuals aged 15–19 experienced a 64.7% higher‐than‐expected rate of new cases in 2021, followed by girls aged 10–14 and women in their 20s. In contrast, the data suggest that older women—especially those aged 40 and above—were less affected than younger individuals by the COVID‐19 pandemic in terms of incidence. This was evidenced by a distinct pattern characterized by a lack of discernible peak in incidence among those aged 50–59 and smaller peaks in onset among those aged 40–49 which occurred in 2020 and 2023. This is a novel finding and extends a literature that has predominantly included younger populations. Notably, the increase in EDs in 2021 appeared to be driven by an excess number of cases of AN, which surged to a level that was 56.9% higher than expected in 2021, before declining to a rate that was 21.0% higher than expected. The number of excess cases of BN was lower despite the slight uptick in 2021 (i.e., 3.3 in 2020, 11.2 in 2021, 4.1 in 2022, and 4.6 in 2023), reflecting a general downward trend for BN. Finally, the excess incidence for males was low overall, decreasing from 2.6 to 1.0 case per 100,000 across the study period. Overall, these patterns align with epidemiological research conducted prior to (Reas and Ro 2018; van Eeden et al. 2023) and during the initial years of the pandemic (e.g., Laskowski et al. 2024; Linardon et al. 2022; Taquet et al. 2021).

Encouragingly, the pandemic‐related surge in incidence affecting girls aged 15–19 underwent a sharp reversal. While adolescents were highly vulnerable to the risk of deteriorating mental health during the height of the pandemic (Devoe et al. 2023; Rodgers et al. 2020), this group appears to have benefitted considerably following the removal of pandemic‐related closures and restrictions. In contrast, rates of new‐onset cases for girls aged 10–14 and for women in their 20s, while improved, remained around 30% higher than expected in 2023. In Norway, schools were closed during the first wave of the COVID‐19 pandemic on March 13, 2020, and gradually re‐opened under strict Infection Prevention and Control (IPC) measures from April 20 (Stebbings et al. 2022). During the second and third waves, Norwegian schools remained largely open, utilizing mitigation strategies such as short‐term closures and distance learning in response to local outbreaks. Although the surge in EDs during the COVID‐19 pandemic occurred worldwide, lockdowns and mitigation policies were local, and additional studies are encouraged to assess post‐pandemic trends in EDs within different regions. Additionally, studies of non‐treatment‐seeking and community samples are warranted to replicate findings, and future studies should continue to monitor incidence to determine whether rates continue to decline or stabilize at a “new normal” level.

Whereas direct comparisons to other investigations are challenging due to methodological differences and should be undertaken with caution, our findings add to an emerging post‐pandemic picture that, despite signs of reversals in upward trends, not all groups have returned to pre‐pandemic levels. The study by Sonne et al. (2024) estimated 653 excess cases (i.e., a 29% increase over expected rates) of incident EDs among individuals aged 6–24 years during the pandemic from March 2020 to January 2022. When isolating our data to approximate their methods for comparison, we estimated 752 excess cases (i.e., a 39% increase over expected rates) for individuals aged 10–24 during a similar time period. Our investigation included additional diagnostic categories, which may explain the slightly higher estimate. In the Sonne et al. (2024) study, women aged 20–24 exceeded expected rates of incident EDs by 32% during the post‐pandemic time period, which is comparable to our finding of a 30.5% excess. The study by Herpertz‐Dahlmann and colleagues (2024) found that while overall hospitalization rates for AN and AAN decreased during the first half of 2023, admissions among children aged 9 to 14 years remained high, with no evidence of decline (Herpertz‐Dahlmann et al. 2024). Similarly, our data indicated that rates among girls aged 10–14 remained approximately 30% higher than expected in 2023, surpassing predictions for a group that had already shown increasing rates even before the pandemic (van Eeden et al. 2023). This finding is worrisome, as research shows those with child‐onset AN (i.e., prior to age 15) experience greater illness severity, life difficulties, and greater lifetime psychiatric comorbidity (Grilo and Udo 2021). Alternatively, increasing incidence rates may be attributed to better detection and improved community awareness, especially among schools and parents. While speculation is beyond our scope, early recognition and rapid referral to effective treatments is nevertheless warranted for this vulnerable group.

Our study has notable limitations which should be acknowledged. Registry‐based studies are limited to case detection and successful treatment‐seeking, meaning that these data invariably provide an underestimate of the true incidence of eating disorders in the general population (Keski‐Rahkonen and Mustelin 2016). This investigation focused on the healthcare‐detected incidence of EDs diagnosed within the secondary or specialized treatment services and does not include primary healthcare services. In Norway, general practitioners (GPs) typically function as a gateway to specialized care, referring out for an in‐depth assessment when an ED is suspected. Registry data are highly susceptible to changes in diagnostic practices and treatment‐seeking behavior over time, or shifts in the accessibility of services as well as the diagnostic profiles of individuals seeking treatment. It is considered a strength that a single diagnostic classification system was utilized without interruption during the entire study period from 2010 to 2023. However, the ICD‐10 is limited in terms of classification, necessitating future studies based on ICD‐11 or DSM‐5 diagnoses to more accurately estimate the incidence of ARFID and BED. We can only infer that these disorders are represented in our dataset within the “other EDs” or total category. Future studies are warranted to understand other demographic indicators or regional differences, also in healthcare utilization, which could provide useful data for national purposes in terms of planning services and identifying geographical differences in risk, inequities, and ascertainment. While it is encouraging that data indicate a reversal in the surge of new‐onset cases warranting specialized care during the COVID‐19 pandemic, community‐based studies are sorely needed for replication because the rate of treatment seeking for an ED is low (Coffino et al. 2019).

This study benefits from a national registry with nearly 100% coverage owing to strict reporting requirements linked to financial compensation, in addition to universal healthcare, a relatively stable population, and reliable census data. The vast majority of studies on the impact of the COVID‐19 pandemic on ED‐related mental health have investigated single‐site or regional hospital admissions, and few studies have extended beyond the peak pandemic years. Single‐site or regional care systems are often vulnerable to ascertainment or selection biases, as it is difficult to discern whether increases in admissions are attributed to relapses or new‐onset cases, as data may be especially prone to inclusion of prevalent, not incident cases. Additionally, we included males and individuals older than 25 years of age, groups that are historically underrepresented in ED research or excluded altogether due to low numbers.

In conclusion, data from a national patient registry show the incidence of healthcare‐detected EDs peaked in 2021, then declined in 2022 and 2023, despite remaining approximately 20% higher than expected. This study represents one of the first to investigate trends in ED incidence beyond the initial years of the COVID pandemic. Findings highlight the lasting—and disproportionate—impact of the COVID‐19 pandemic on the risk and burden of ED‐related mental health, especially for younger females and individuals affected by AN. Ongoing research is needed to monitor temporal trends in incidence and to determine whether rates continue to decline or stabilize over time.

Author Contributions

Deborah Lynn Reas: conceptualization, data curation, investigation, methodology, writing – original draft. Gunnar Rø: formal analysis, methodology, writing – review and editing. Øyvind Rø: conceptualization, data curation, methodology, supervision, writing – review and editing.

Conflicts of Interest

The authors declare no conflicts of interest.

Supporting information

Figure S1. Observed versus expected incidence (95% CI) of any ED in 2020, 2021, 2022, and 2023 based on pre‐pandemic trends for males and females aged 10–59 years.

Figure S2. Observed versus expected incidence (95% CI) of any ED for females in 2020, 2021, 2022, and 2023 based on pre‐pandemic trends by age group.

Figure S3. Observed versus expected incidence (95% CI) for females in 2020, 2021, 2022, and 2023 based on pre‐pandemic trends by diagnostic group.

EAT-58-1469-s001.docx (505.1KB, docx)

Reas, D. L. , Rø G., and Rø Ø.. 2025. “Trends in the Observed Versus Expected Incidence of Eating Disorders Before, During, and After the COVID−19 Pandemic: A National Patient Registry Study.” International Journal of Eating Disorders 58, no. 8: 1469–1476. 10.1002/eat.24443.

Action Editor: Ruth Striegel Weissman

Funding: The authors received no specific funding for this work.

Data Availability Statement

The data that support the findings of this study derive from the Norwegian Patient Registry [https://www.fhi.no/he/npr/] and are publicly available upon application to the Norwegian Institute of Public Health at https://helsedata.no/.

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Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

Figure S1. Observed versus expected incidence (95% CI) of any ED in 2020, 2021, 2022, and 2023 based on pre‐pandemic trends for males and females aged 10–59 years.

Figure S2. Observed versus expected incidence (95% CI) of any ED for females in 2020, 2021, 2022, and 2023 based on pre‐pandemic trends by age group.

Figure S3. Observed versus expected incidence (95% CI) for females in 2020, 2021, 2022, and 2023 based on pre‐pandemic trends by diagnostic group.

EAT-58-1469-s001.docx (505.1KB, docx)

Data Availability Statement

The data that support the findings of this study derive from the Norwegian Patient Registry [https://www.fhi.no/he/npr/] and are publicly available upon application to the Norwegian Institute of Public Health at https://helsedata.no/.

Articles from The International Journal of Eating Disorders are provided here courtesy of Wiley

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