Abstract
Background
The COVID-19 pandemic prompted rapid expansion of virtual specialist care, yet its sustainability and environmental implications remain unclear. We evaluated temporal trends in virtual inflammatory bowel disease (IBD) care and quantified associated reductions in travel-related carbon emissions.
Methods
We conducted a population-based cohort study of individuals with IBD in Ontario, using linked ICES administrative data. Individuals with established IBD as of April 1, 2020, were followed through March 31, 2025. Outcomes included quarterly rates of virtual IBD specialist visits per 100 IBD capita, the proportion delivered virtually, and estimated carbon emissions avoided from reduced travel. Logistic regression identified predictors of ongoing virtual care.
Results
Among 98 099 individuals with IBD, 95% of specialist encounters among 62 265 patients with any visit were virtual during the first pandemic fiscal year. Virtual visit rates declined after 2021 and stabilized at approximately one-third of encounters by 2023-2025, while total ambulatory rates were modestly lower than pre-pandemic baseline. Of patients with a virtual visit in 2020-2021, 28% had one in 2023-2024. Older age, lower comorbidity, and residence in low-access regions were associated with reduced odds of continued virtual care. In the first pandemic year, virtual care was estimated to avoid 1268 tonnes of CO2 emissions, equivalent to the annual emissions of 275 passenger cars.
Conclusions
Virtual IBD specialist care was associated with substantial reductions in estimated travel-related carbon emissions, which diminished as care returned to in-person delivery. Sustainable hybrid care models may preserve environmental benefits while maintaining specialist access.
Keywords: inflammatory bowel disease, environmental sustainability, carbon footprint, telemedicine
Introduction
Inflammatory bowel disease (IBD), encompassing Crohn’s disease (CD) and ulcerative colitis (UC), is a chronic, immune-mediated disorder that typically follows a relapsing-remitting course and often begins in adolescence or early adulthood.1,2 Many patients require long-term immunomodulators or biologic therapy and periodic objective monitoring to maintain remission and prevent complications.1–3 Treat-to-target approaches, therefore, emphasize recurrent assessment and timely therapy optimization to improve long-term outcomes.3 Population-based studies have shown improved outcomes when IBD care is delivered by gastroenterologists, including lower postoperative utilization after CD surgery and improved outcomes among hospitalized ulcerative colitis patients.4,5 As the management of IBD involves repeated outpatient encounters, the modality of delivering specialist care has implications for access, patient burden, and health-system sustainability.
In early 2020, COVID-19 prompted a rapid pivot to virtual ambulatory care in Ontario. The Ontario Ministry of Health introduced temporary OHIP billing codes enabling routine assessments by phone or video starting March 14, 2020.6 In primary care, office visits fell nearly 80% while virtual visits increased more than fifty-fold, accounting for approximately 71% of all visits from March through July 2020.6 IBD practice patterns changed similarly. A global survey by the International Organization for the Study of IBD documented widespread conversion of IBD clinics from in-person to virtual care during 2020.7 In Ontario IBD specialist care, in-person outpatient gastroenterology visits declined 69% quarter-over-quarter with a concurrent 591% rise in virtual visits during the early pandemic phase.8 Yet virtual care use has decreased since the initial lockdowns, raising questions about the durability of virtual chronic disease management and the sustainability of any downstream benefits.9
Reducing greenhouse gas emissions from health care has become a priority, and patient travel to outpatient appointments is a modifiable source. A systematic review found telemedicine consistently lowers the carbon footprint of care compared with in-person visits (0.70-372 kg CO2e saved per consultation), largely through avoided carbon emissions attributable to transportation.10 In Ontario, an ICES-led study estimated that virtual physician care from March 2020 to December 2021 avoided 3.2 billion kilometres of travel and 545-658 million kilograms of CO2 emissions.11 To provide context, the Canadian healthcare system is responsible for approximately 4%-5% of national greenhouse gas emissions, with patient travel accounting for approximately 10% of health-related emissions.12,13 Gastroenterology-specific work in Ontario and Manitoba has likewise quantified meaningful travel-related emissions for in-person clinic visits, suggesting that high-frequency chronic care, such as IBD, may offer a substantial opportunity.14,15 As such, using population-level data, we aim to evaluate the sustainability of virtual healthcare delivery by examining temporal trends following the COVID-19 pandemic and characterizing the estimated travel-related carbon emissions associated with virtual IBD care. This study uniquely combines longitudinal evaluation of virtual care utilization with quantification of associated environmental impact at a population level within a single chronic disease cohort. Our work extends the assessment of sustainability beyond prior single-centre analyses to a province-wide, IBD-specific cohort with longitudinal follow-up through the post-pandemic period. It concurrently identifies sociodemographic predictors of sustained virtual care use that may be relevant when considering equitable hybrid care delivery.
Methods
Study design and setting
We conducted a population-based cohort study in Ontario, Canada, using routinely collected health administrative data housed at ICES. The index date was April 1, 2020, and individuals were followed within the observation window through March 31, 2025. To evaluate persistence of IBD virtual care utilization and associated environmental impact, we compared a pandemic-era period (Period 1: April 1, 2020, to March 31, 2021) with a later post-pandemic period (Period 2: April 1, 2023, to March 31, 2024). Outcomes were summarized by calendar quarter within each period.
Data sources
We used ICES-held datasets including the Ontario Health Insurance Plan (OHIP) physician claims database, the Registered Persons Database (RPDB), the Canadian Institute for Health Information Discharge Abstract Database (CIHI-DAD), the ICES Physician Database (IPDB), the Local Health Integration Network (LHIN) geography file, and the ICES-derived Ontario Crohn’s and Colitis Cohort (OCCC).16 Datasets were linked using a unique encoded identifier.
Study population
The study cohort included individuals registered in RPDB from April 1, 2019, to March 31, 2025, who had a diagnosis of IBD in the OCCC on or before April 1, 2020. The OCCC is an ICES-derived, continually updated registry of individuals with inflammatory bowel disease, constructed using a validated case-finding algorithm applied to provincial administrative health data. For individuals older than 18 years of age, the algorithm identifies IBD based on the presence of at least 5 physician encounters or hospital admissions coded for IBD within a 4-year period and demonstrates high diagnostic performance, with a reported sensitivity of 92%, specificity of 99%, and positive predictive value of 81%.17 Individuals diagnosed before age 18 years were identified using a separately validated paediatric IBD algorithm. For these paediatric cases, IBD was defined as either: (1) for patients with a sigmoidoscopy or colonoscopy procedure code, 2 hospital admissions with an IBD diagnosis or 4 OHIP claims or emergency department visits with an IBD diagnosis within 3 years; or (2) for patients without a sigmoidoscopy or colonoscopy procedure code, 3 hospital admissions with an IBD diagnosis or 7 OHIP claims or emergency department visits with an IBD diagnosis within 3 years.18 The OCCC captures all diagnosed IBD cases across Ontario, functioning as a population-based cohort that reflects real-world patterns of IBD care and outcomes in both urban and rural settings.
Predictor variables
The primary exposure was calendar time, measured in quarterly intervals. We defined 2 1-year study periods for comparison: a pandemic-era period (Period 1, April 1, 2020, to March 31, 2021) and a post-pandemic period (Period 2, April 1, 2023, to March 31, 2024). Period 2 was selected as a duration-matched comparator, representing a time when patterns of virtual and in-person care delivery had stabilized following the acute pandemic transition. A third period (Period 3: April 1, 2024, to March 31, 2025) was defined for use in sensitivity analysis of the multivariable logistic regression.
Baseline covariates included age group (<18 years, 18-64 years, ≥65 years), sex, neighbourhood income quintile (derived from postal code), comorbidity burden using Johns Hopkins ACG software (categorized into quartiles), local health integration network (LHIN) region categorized by gastroenterologist access (low: LHIN 1, 12, 13, 14; medium: LHIN 2, 3, 4, 5, 6, 8, 9, 10, 11; high: LHIN 7), rurality, and disease duration from the OCCC. LHINs are 14 geographic regions historically used by the Ontario health system to plan and coordinate publicly funded health services.
Outcome variables
The primary outcomes were quarterly rates of virtual specialist visits per IBD capita and the proportion of total IBD specialist visits that were virtual. Specialist encounters were defined as ambulatory physician visits billed to the Ontario Health Insurance Plan (OHIP) with an IBD diagnosis code (555 or 556) and provided by a gastroenterology specialist. Visits occurring in inpatient or emergency department settings were excluded based on OHIP codes associated with those types of visits. We also excluded in-person ambulatory visits with concomitant endoscopy procedure codes. Physician specialty was determined through linkage with the ICES Physician Database, with gastroenterologists identified by a gastroenterology specialty code (41) or by an internal medicine specialty code (13) among physicians performing more than 50 colonoscopies annually.19 Encounters were classified as virtual or in-person according to the presence of an associated virtual care billing code (B100, B200, B203, K081, K082, K083, K300, K301) attached to the primary service claim.20 As part of the updated provincial virtual care funding framework introduced on December 1, 2022, billing codes K300 (video) and K301 (telephone) were implemented to distinguish video-based and telephone-based virtual visits, respectively.21 We used these codes to examine temporal trends in modality-specific virtual care delivery.
At the individual level, we created indicator variables for whether each person had ≥1 virtual specialist visits in Period 1, Period 2, and Period 3. We also enumerated total virtual visits in each period. Among individuals with ≥1 virtual visit in Period 1, we created an indicator variable for those who also had at least one virtual visit for Period 2 and Period 3. We also calculated the ratio of Period 2 to Period 1 virtual visit counts and created an indicator variable for ratios ≥50%.
Distance travelled and carbon emissions avoided
For each virtual IBD specialist visit, we estimated the round-trip travel distance that would have occurred had the visit been in-person by linking the patient’s 6-digit residential postal code (RPDB) and the specialist’s 6-digit registered practice postal code (IPDB). Distances (kilometres) were calculated by converting postal codes to latitude/longitude using PCCF2021 and computing geographic distance using geodistance methods, then multiplying by 2 for return travel. When an individual saw more than one physician on the same day, we selected the longer of the distances for that person-day. For physicians who practiced at more than one location, we assumed that each gastroenterologist’s registered IPDB practice postal code represented their primary ambulatory clinic site. Six-digit postal codes generally represent small geographic areas. However, in rural and remote regions, a single postal code may cover a substantially larger area, contributing additional uncertainty to our distance estimates.
Carbon emissions avoided were estimated by multiplying total kilometres avoided by an emission factor, assuming all avoided travel would otherwise have been undertaken by car, consistent with the methodology described by Welk et al.11 In their analysis of Ontario administrative data, they assumed a conservative reduction of 206 g CO2 per kilometre of travel by car avoided.11 Sensitivity analysis was performed using a factor of 260 g CO2 per kilometre as described by Galts et al which accounted for non-tailpipe emissions and road life-cycle assessments.14 Our study did not ascribe any carbon emissions related to virtual care as those were deemed relatively negligible based on previous life cycle assessments.22 Cumulative carbon emissions reductions were calculated for each fiscal year (April 1 through March 31) using both carbon emission factors and converted to metric tonnes.
Statistical analysis
Descriptive statistics and multivariable logistic regression were performed using SAS Enterprise Guide version 8.3 (SAS Institute Inc., Cary, NC, United States). We calculated quarterly visit rates per IBD capita and the quarterly proportion of specialist visits that were virtual and performed time-interrupted series analysis from April 1, 2020, to March 31, 2025, to assess for statistically significant trends. We performed descriptive statistics comparing rates of virtual IBD specialist visits and the proportion of total IBD visits that were virtual in Period 2 compared with Period 1. Among individuals who had at least one virtual visit in Period 1, we determined the proportion who had at least one virtual visit in Period 2. Multivariable logistic regression was performed among IBD patients who remained alive and residing in Ontario throughout the entire study period (April 1, 2020-March 31, 2025) to identify predictors of ongoing utilization of virtual care in Period 2, defined as at least one virtual IBD visit. We included age, sex, neighbourhood income, comorbidity, regional access to specialist, and rurality as covariates in the model. As a sensitivity analysis, the same multivariable logistic regression was performed assessing predictors of ongoing care in Period 3.
Quarterly visit rates were analyzed using segmented interrupted time series regression to evaluate temporal changes in virtual, total, and in-person IBD specialist visit utilization. These analyses were conducted using Stata version 18.0 (StataCorp LLC, College Station, TX, United States). Generalized linear models with a negative binomial distribution were used to account for overdispersion. An offset term for the logarithm of the eligible IBD population per quarter was included to model visit rates per capita.
Ethics
ICES is a prescribed entity under section 45 of Ontario’s Personal Health Information Protection Act. Section 45 authorizes ICES to collect personal health information, without consent, for the purpose of analysis or compiling statistical information with respect to the management, evaluation, or monitoring of the allocation of resources to the government-funded health system. Projects conducted under section 45, by definition, do not require review by a Research Ethics Board. This project was conducted under section 45 and approved by ICES’ Privacy and Compliance Office.
Results
There were 98 099 IBD patients (52% UC, 44% CD, and 4% IBD-unclassified) in the cohort with a mean duration of disease (±SD) of 9.6 ± 6.1 years during the COVID-19 pandemic (Period 1). Within this cohort, 62 265 IBD patients had at least one IBD-related visit with a GI specialist during that same period, and among those, 43 129 patients had at least one virtual specialist visit. The baseline demographic and clinical characteristics of this cohort are shown in Table 1. During the initial pandemic period, 95% of all IBD specialist encounters among the 62 265 individuals with any specialist visit were delivered virtually.
Table 1.
Baseline characteristics of the inflammatory bowel disease cohort, overall and by specialist visit and virtual specialist visit use.
| Entire cohort (N = 98 099) | Any IBD specialist visit (N = 62 265) | Any virtual IBD specialist visit (N = 43 129) | |
|---|---|---|---|
| Mean age ± SD | 50.4 ± 16.8 | 48.2 ± 16.4 | 47.7 ± 16.5 |
| Age category, n (%) | |||
| <18 years | 2146 (2) | 1317 (2) | 801 (2) |
| 18-64 years | 74 938 (76) | 50 022 (80) | 34 908 (81) |
| 65+ years | 21 015 (21) | 10 926 (18) | 7420 (17) |
| Sex, n (%) | |||
| Women | 50 864 (52) | 32 381 (52) | 22 723 (53) |
| Men | 47 235 (48) | 29 884 (48) | 20 406 (47) |
| IBD diagnosis, n (%) | |||
| Crohn’s disease | 43 194 (44) | 29 155 (47) | 20 900 (49) |
| Ulcerative colitis | 51 288 (52) | 31 858 (51) | 21 473 (50) |
| Unclassified | 3617 (4) | 1252 (2) | 756 (2) |
| IBD duration, mean (±SD) (years) | 9.6 ± 6.1 | 8.7 ± 6.0 | 8.4 ± 6.0 |
| Income quintile, n (%) | |||
| Quintile 1 | 15 714 (16) | 9209 (15) | 6362 (15) |
| Quintile 2 | 18 523 (19) | 11 471 (18) | 7902 (18) |
| Quintile 3 | 19 794 (20) | 12 653 (20) | 8834 (21) |
| Quintile 4 | 20 472 (21) | 13 334 (21) | 9268 (22) |
| Quintile 5 | 23 406 (24) | 15 488 (25) | 10 691 (25) |
|
|||
| Quartile 1 | 24 553 (25) | 12 145 (20) | 7478 (17) |
| Quartile 2 | 29 202 (30) | 19 396 (31) | 13 420 (31) |
| Quartile 3 | 17 977 (18) | 12 505 (20) | 8881 (21) |
| Quartile 4 | 26 367 (27) | 18 219 (30) | 13 350 (31) |
| Regional specialist access, n (%) | |||
| Low | 16 378 (17) | 9495 (15) | 6511 (15) |
| Medium | 73 280 (75) | 47 275 (76) | 32 710 (76) |
| High | 8441 (9) | 5495 (9) | 3908 (9) |
| Rurality, n (%) | |||
| Urban | 86 879 (89) | 55 806 (90) | 38 801 (90) |
| Rural | 11 061 (11) | 6370 (10) | 4272 (10) |
Trends in virtual healthcare utilization
Following the pandemic period between 2021 and 2025, total IBD specialist visit rates declined while healthcare delivery shifted from predominantly virtual to predominantly in-person (Figure 1). In 2020 and early 2021, virtual visit rates were high, approximately 22-26 visits per 100 IBD capita per quarter, whereas in-person visits were low at roughly 1-3 per 100 IBD capita per quarter. During this period, total visit rates ranged from approximately 24-27 per 100 IBD capita per quarter, and the proportion of visits conducted virtually was very high, generally exceeding 85%. Between the second quarters of 2021 and 2023, virtual visit rates fell sharply at a relative quarterly rate of 15% (95% CI: 12%-17%) to approximately 6-7 visits per 100 IBD capita per quarter and remained at this lower level through early 2025. In contrast, in-person visit rates increased substantially between the first quarter of 2022 and the third quarter of 2023, rising by a quarterly relative rate of 32% (95% CI: 25%-39%) to approximately 11-14 visits per 100 IBD capita per quarter in 2023 and remaining at that level until 2025. Consistent with these changes, the proportion of IBD specialist visits delivered virtually declined to approximately one-third of visits by 2023 through 2025. Despite the rebound in in-person care, total visit rates started to decline in the second quarter of 2021 by a relatively quarterly rate of 3% (95% CI: 1%-4%), stabilizing at approximately 18-21 visits per 100 IBD capita per quarter in the later period.
Figure 1.
Quarterly trends in IBD specialist visit rates and proportion delivered virtually, 2020-2025. Rates of total (purple solid line), virtual (red dotted line), and in-person (blue dashed line) IBD specialist visits per 100 IBD capita are shown by quarter (left y-axis). The denominator is the entire Ontario IBD cohort as of April 1, 2020 (n = 98 099). Grey bars represent the proportion of visits delivered virtually (right y-axis). Virtual visit rates declined after 2021 with a corresponding increase in in-person visits, while total visit rates were modestly lower than pre-pandemic baseline.
Among IBD patients who had at least one virtual visit during Period 1 (April 1, 2020-March 31, 2021), 28% had at least one virtual visit during Period 2 (April 1, 2023-March 31, 2024). Just over one-fifth (22%) of those who had a virtual visit in Period 1 maintained at least 50% of those visits virtually in Period 2. In multivariable analysis, age was strongly associated with virtual IBD specialist visit use (Table 2). Compared with individuals younger than 18 years, those aged 18-64 years had substantially lower odds of a virtual visit (adjusted odds ratio [OR], 0.39; 95% CI: 0.34-0.44), and those aged 65 years and older had even lower odds (aOR, 0.24; 95% CI: 0.21-0.28). Higher comorbidity burden was associated with greater virtual care use, with individuals in the highest ACG quartile having increased odds compared with the lowest quartile (aOR, 1.19; 95% CI: 1.11-1.27). Regional access to specialist care was also a significant predictor, with patients residing in high-access regions having markedly higher odds of a virtual visit use relative to low-access regions (adjusted OR, 1.54; 95% CI: 1.41-1.69). Those in higher income quintiles also showed a modest increase in odds of receiving ongoing virtual care (fifth vs. first quintile: OR, 1.10; 95% CI: 1.02-1.18). Sensitivity analysis assessing predictors of virtual care utilization in Period 3 showed similar findings (Table 2).
Table 2.
Multivariable logistic regression of predictors of ongoing virtual care use.
| Adjusted odds ratio (95% CI) |
||
|---|---|---|
| Period 2 (April 1, 2023-March 31, 2024) | Period 3 (April 1, 2024-March 31, 2025) | |
| Age | ||
| <18 | Ref | Ref |
| 18-64 | 0.39 (0.34-0.44) | 0.46 (0.40-0.53) |
| 65+ | 0.24 (0.21-0.28) | 0.27 (0.23-0.31) |
| Sex | ||
| Male | Ref | Ref |
| Female | 1.04 (1.00-1.09) | 1.02 (0.97-1.06) |
| IBD type | ||
| Crohn’s disease | Ref | Ref |
| Ulcerative colitis | 0.89 (0.85-0.93) | 0.84 (0.81-0.88) |
| IBD-unclassified | 0.53 (0.43-0.66) | 0.51 (0.41-0.63) |
| Income quintile | ||
| 1 | Ref | Ref |
| 2 | 1.11 (1.03-1.19) | 1.11 (1.03-1.20) |
| 3 | 1.07 (0.99-1.15) | 1.13 (1.05-1.22) |
| 4 | 1.09 (1.01-1.17) | 1.13 (1.05-1.22) |
| 5 | 1.10 (1.02-1.18) | 1.09 (1.02-1.17) |
| Comorbidity burden (ACG quartile) | ||
| 1 | Ref | Ref |
| 2 | 1.14 (1.07-1.22) | 1.15 (1.07-1.22) |
| 3 | 1.14 (1.06-1.22) | 1.21 (1.13-1.30) |
| 4 | 1.19 (1.11-1.27) | 1.31 (1.23-1.40) |
| Geographic access to specialists | ||
| Low | Ref | Ref |
| Medium | 1.09 (1.02-1.16) | 1.15 (1.08-1.22) |
| High | 1.54 (1.41-1.69) | 1.65 (1.51-1.81) |
| Rural residence | ||
| Urban | Ref | Ref |
| Rural | 0.93 (0.86-1.00) | 0.99 (0.92-1.06) |
Beginning December 1, 2022, virtual visit modality was distinguished using billing codes for video (K300) and telephone (K301) encounters. Between December 1, 2022, and March 31, 2023, there were 3751 video visits and 5107 telephone visits, with telephone visits accounting for 57.7% of modality-specific virtual encounters during this period. In Period 2 (April 2023-March 2024), there were 12 686 video visits and 13 405 telephone visits, with telephone visits representing 51.4% of virtual encounters.
Travel-related reduction in carbon emissions
During the first pandemic fiscal year from April 2020 through March 2021, virtual IBD specialist visits among the IBD cohort were associated with 1268 tonnes of avoided CO2 emissions using the primary emission factor of 206 g per kilometre (Figure 2). Under the higher emission factor of 260 g per kilometre in sensitivity analyses, avoided emissions during this period increased proportionally. In fiscal year 2021-2022, avoided emissions totalled 1142 tonnes using the primary estimate, declining to 779 tonnes in fiscal year 2022-2023. By fiscal year 2023-2024, cumulative avoided emissions attributable to virtual IBD specialist visits decreased to 478 tonnes, with 536 tonnes avoided in fiscal year 2024-2025. Estimates were consistently higher under the 260 g per kilometre sensitivity assumption, but demonstrated the same temporal pattern of declining annual carbon savings as virtual care utilization decreased.
Figure 2.
Annual travel-related carbon emissions avoided through virtual IBD specialist care, 2020-2025. Estimated reductions in CO2 emissions attributable to avoided patient travel from virtual IBD specialist visits are shown by fiscal year. Black bars represent the primary estimate using 206 g CO2 per kilometre, and hatched bars represent sensitivity estimates using 260 g CO2 per kilometre. Avoided emissions were highest in 2020-2021 and declined in subsequent years as virtual care utilization decreased.
At the individual visit level, the mean carbon emissions avoided per virtual encounter increased over time. At the beginning of the 2020-2021 fiscal year, the mean avoided emissions ± standard deviation (SD) were approximately 14 ± 37 kg CO2 per visit. By the end of the 2024-2025 fiscal year, the mean increased to approximately 22 ± 42 kg CO2 per visit, suggesting that although fewer virtual visits occurred in later years, they were increasingly associated with longer travel distances and greater per-visit carbon savings.
Discussion
In this population-based study of individuals with inflammatory bowel disease in Ontario, we found that the rapid expansion of virtual specialist care during the COVID-19 pandemic was estimated to be associated with substantial reductions in assumed travel-related carbon emissions. During the first pandemic fiscal year, when approximately 95% of IBD specialist encounters were delivered virtually, virtual care was associated with 1268 tonnes of avoided CO2 emissions using conservative assumptions. However, these environmental benefits declined markedly in subsequent years as care shifted back toward in-person delivery. By fiscal years 2023-2025, annual carbon savings had fallen by more than half compared with the pandemic peak, reflecting a sustained reduction in virtual care utilization.
Importantly, the transition from virtual to in-person care was not accompanied by a recovery in overall specialist visit rates. Rather, total ambulatory IBD specialist visit rates remained lower than early pandemic levels. Of note, when compared with the pre-pandemic IBD specialist visit rate of approximately 23-30 in-person visits per 100 IBD capita per quarter observed in our prior 2016-2020 Ontario population-based study, post-pandemic total visit rates of 18-21 per 100 IBD capita per quarter represent a modest decrease below pre-pandemic baseline.8 Both studies used the same ICES databases, OCCC case-finding algorithm, OHIP billing code definitions, and analytic approach. This suggests that the post-pandemic period was characterized not only by a modality shift but possibly by a modest reduction in outpatient specialist utilization relative to pre-pandemic baseline. The clinical significance of this modest decline is uncertain. It may reflect the continuation of a pre-existing downward secular trend in outpatient specialist visit rates that was already evident before the pandemic, a transient pandemic-driven spike in visits returning to baseline, or a combination of factors.8 Without complementary clinical outcome data, it is not possible to distinguish among these explanations. Continued attention to specialist access remains warranted given that gastroenterology care has been associated with improved health outcomes such as lower postoperative healthcare utilization in Crohn’s disease and improved outcomes among hospitalized ulcerative colitis patients.4,5 Chronic IBD management relies on recurrent monitoring and timely therapy optimization within treat-to-target frameworks.3 Whether the observed visit rate changes reflect decreased access or a return to pre-pandemic norms cannot be determined from our data.
Virtual care use declined sharply around the time the Ontario Ministry of Health introduced changes to virtual care reimbursement in December 2022.23 The new framework included additional billing requirements and reduced payment for telephone visits to 85% of the equivalent in-person fee. This is notable because telephone visits accounted for the majority of virtual specialist encounters during the pandemic. In our cohort, the proportional contribution of telephone visits to virtual encounters declined modestly from 57.7% in the months immediately preceding the December 2022 fee change to 51.4% in Period 2, suggesting that the overall decline in virtual care was driven by reductions in both modalities but with a relatively steeper decline in telephone visits coinciding with the December 2022 reimbursement changes. The timing suggests that reimbursement policy may have contributed to the contraction of virtual care. However, because we did not have a contemporaneous comparator group of physicians or services whose reimbursement was unchanged, we cannot establish a causal relationship between reimbursement reform and the decline in virtual visits. Concurrent factors, including resumption of in-person workflows, lifting of pandemic restrictions, and shifts in provider and patient preferences, may also have contributed. These findings raise the possibility that payment structures may influence healthcare delivery patterns, though implications for access and environmental sustainability require further investigation.
Equitable access is also an important consideration. Individuals residing in regions with lower specialist access were significantly less likely to sustain virtual care use in the post-pandemic period, while patients in high-access regions had substantially greater odds of ongoing virtual care. Possible explanations for the lower rate of virtual care use among patients in remote communities in the post-pandemic period include limited broadband internet infrastructure required for video consultations, fewer locally based gastroenterologists offering longitudinal virtual follow-up, and potentially greater patient preference for in-person consultations among individuals already accustomed to traveling for specialist care. Rather than mitigating geographic inequities, virtual care in its post-pandemic era may be reinforcing existing patterns of access to gastroenterologists. Prior work has documented rural and regional disparities in IBD care across Canada, and our findings suggest that virtual care has not yet fully realized its potential to bridge these gaps.19,24 Ensuring that virtual delivery models expand access in underserved regions will be critical if virtual care is to function as a tool for health equity rather than convenience.
From an environmental perspective, our findings, which estimate avoided emissions under modelled assumptions rather than directly measuring transportation choices, align with prior evidence demonstrating that telemedicine may reduce healthcare-related carbon emissions primarily through avoided transportation.10,11,14,25 The 1268 tonnes of CO2 avoided during the first pandemic fiscal year correspond to the annual emissions of approximately 275 passenger vehicles.26 Although modest relative to Canada’s total health sector emissions, which account for approximately 4%-5% of national greenhouse gas output,27 this magnitude is notable for a single chronic disease population and highlights the measurable climate impact of outpatient care delivery models. As health systems globally strive to fulfil net-zero commitments, virtual chronic disease management warrants further evaluation as a potential strategy to reduce transportation-related emissions. A complementary single-centre Manitoba analysis of 5690 telemedicine encounters from a tertiary-care gastroenterology clinic estimated approximately 244 000 kg of CO2e avoided over 2 years, with rural patients accounting for over 90% of the avoided emissions.15 The consistency of these findings with our Ontario population-based IBD cohort lends further evidence that telemedicine meaningfully reduces travel-related emissions in Canadian gastroenterology practice and that rural and remote patients derive disproportionate environmental benefit.
This study has several limitations. First, we lacked individual-level data on IBD disease activity or severity. Patients with active disease may have been preferentially seen in person, while those in clinical remission were considered more suitable for virtual care. Observed declines in virtual visit rates over time could therefore reflect changes in case mix or disease activity rather than purely policy or preference shifts. This unmeasured confounding is an important limitation. Second, carbon emissions were estimated indirectly based on travel distance and standardized emission factors rather than measured transportation mode or actual emissions, and individual variation in travel behaviour could not be captured. We assumed all avoided trips would have been undertaken by car. If some patients would have travelled by public transit or active transportation (eg, walking or biking), or would not have travelled to the visit at all, the realized emissions reductions would be lower than our estimates. Our values, therefore, represent assumed rather than directly measured CO2 emissions savings. Administrative data do not provide detailed clinical information regarding disease activity or visit appropriateness, limiting our ability to determine whether declining virtual care reflects optimal care delivery or unmet need. Although the OCCC algorithm is validated and widely used, its reported positive predictive value of 81% means approximately 1 in 5 identified cases may be false positives, which could introduce some misclassification bias into our cohort. The temporal association between reimbursement changes and virtual care decline does not establish causation, as we lacked a contemporaneous comparator population whose virtual care reimbursement was unchanged. Our analysis focused on travel-related emissions and did not incorporate other contributors to healthcare-related carbon footprint, such as digital infrastructure or facility-level energy use. However, prior work suggests that facility-level emissions attributable to ambulatory encounters account for less than 1% of total emissions differences, with transportation remaining the dominant driver.10,22 Finally, while we observed reductions in total ambulatory specialist visits over time, we were unable to assess downstream clinical outcomes associated with these shifts in care delivery.
In conclusion, virtual IBD specialist care during the COVID-19 pandemic was associated with substantial reductions in travel-related carbon emissions, but these environmental gains diminished as care shifted back toward in-person delivery. Future research should evaluate whether sustainable hybrid care models can preserve environmental benefits while ensuring equitable access to high-quality specialist care.
Supplementary Material
Contributor Information
Luke J Nguyen, Mount Sinai Centre for Inflammatory Bowel Disease, Toronto, Ontario, Canada; Faculty of Health Sciences, Queen’s University, Kingston, Ontario, Canada.
Vivian Huang, Mount Sinai Centre for Inflammatory Bowel Disease, Toronto, Ontario, Canada; Division of Gastroenterology and Hepatology, University Health Network and Sinai Health System, University of Toronto, Toronto, Ontario, Canada.
Peter Habashi, Mount Sinai Centre for Inflammatory Bowel Disease, Toronto, Ontario, Canada.
Daniel McCormack, ICES, Toronto, Ontario, M4N 3M5, Canada.
Christopher A Chong, Faculty of Health Sciences, Queen’s University, Kingston, Ontario, Canada.
Parul Tandon, Division of Gastroenterology and Hepatology, University Health Network and Sinai Health System, University of Toronto, Toronto, Ontario, Canada; ICES, Toronto, Ontario, M4N 3M5, Canada; Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Ontario, M5T 3M6, Canada.
Author contributions
L.J.N.: Study conception; data analysis; drafting of manuscript. V.W.H.: Study conception, review of manuscript. P.H.: Study conception, review of manuscript. D.M.: Study conception; data analysis; review of manuscript. C.A.C.: Study conception; review of manuscript. P.T.: Study conception; data analysis; review of manuscript.
Funding
This study was supported by ICES, which is funded by an annual grant from the Ontario Ministry of Health (MOH) and the Ministry of Long-Term Care (MLTC). This study also received funding from: Crohn’s and Colitis Canada, The Leona M and Harry B Helmsley Charitable Trust. This document used data adapted from the Statistics Canada Postal CodeOM Conversion File, which is based on data licensed from Canada Post Corporation, and/or data adapted from the Ontario Ministry of Health Postal Code Conversion File, which contains data copied under license from ©Canada Post Corporation and Statistics Canada. Parts of this material are based on data and/or information compiled and provided by: CIHI and the Ontario Ministry of Health. The analyses, conclusions, opinions, and statements expressed herein are solely those of the authors and do not reflect those of the funding or data sources; no endorsement is intended or should be inferred.
Conflicts of interest
Conflict of interest disclosure forms (ICMJE) have been collected for all co-authors and can be accessed as supplementary material.
Data availability
The dataset from this study is held securely in coded form at ICES. While legal data sharing agreements between ICES and data providers (eg, healthcare organizations and government) prohibit ICES from making the dataset publicly available, access may be granted to those who meet pre-specified criteria for confidential access, available at https://www.ices.on.ca/DAS (email: das@ices.on.ca). The full dataset creation plan and underlying analytic code are available from the authors upon request, understanding that the computer programs may rely upon coding templates or macros that are unique to ICES and are therefore either inaccessible or may require modification.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Data Availability Statement
The dataset from this study is held securely in coded form at ICES. While legal data sharing agreements between ICES and data providers (eg, healthcare organizations and government) prohibit ICES from making the dataset publicly available, access may be granted to those who meet pre-specified criteria for confidential access, available at https://www.ices.on.ca/DAS (email: das@ices.on.ca). The full dataset creation plan and underlying analytic code are available from the authors upon request, understanding that the computer programs may rely upon coding templates or macros that are unique to ICES and are therefore either inaccessible or may require modification.