About

Andrea J. Apter, MD, MA, MSc, is a Professor and Chair of Medicine in the Department of Medicine at the University of Pennsylvania's Perelman School of Medicine. She is also a Senior Fellow at the Center for Public Health Initiatives. Her clinical expertise includes allergy-immunology, asthma, drug allergy, rhinitis, sinusitis, urticaria, food allergy, immunodeficiency, anaphylaxis, angioedema, and atopic dermatitis. Her research focuses on epidemiology related to asthma, drug allergy, health disparities, adherence, patient-physician communication, clinical research, and quality of life. She has contributed to understanding health equity in patient-reported outcomes and has published extensively on asthma morbidity measures, health disparities within allergy and immunology, and communication during the COVID-19 pandemic for adults with asthma from low-income neighborhoods.

Research topics

• Medicine
• Family medicine
• Intensive care medicine
• Pediatrics
• Internal medicine

Selected publications

• Off-schedule patient-reported outcomes in adults with asthma may influence research results

  Journal of Allergy and Clinical Immunology · 2025-05-23

  letterOpen accessSenior author
  PublisherOA PDFDOI

• Evaluation of Asthma Status Classification Consistency in Electronic Health Records by Asthma Specialist Review Versus Rules-based Algorithms

  American Journal of Respiratory and Critical Care Medicine · 2025-05-01

  article

  Abstract Rationale: Many research studies rely on the accurate identification of people with asthma using algorithms applied to Electronic Health Record (EHR) data. Although machine learning and rules-based approaches applied to codified variables and extracted notes have reported high classification accuracy, few reports describe in detail the creation of gold standard classifications that precede the creation of predictive models or involve asthma specialists in creating such labels. We sought to measure the consistency of asthma classification according to data in the EHR by asthma specialists, and whether such labels were consistent with commonly applied rules-based definitions of asthma. Methods: We obtained EHR data for 600 adults who had encounters at Penn Medicine with International Classification of Diseases, Tenth Revision (ICD-10) code for asthma (i.e., J45[asterisk]) between January 2017 and August 2023, of these: 200 had no prescription for short-acting beta agonist (SABA) or inhaled corticosteroid (ICS); 200 had a SABA prescription, and 200 had an ICS prescription. Asthma specialists (1 pulmonologist, 3 allergists/immunologists) iteratively created a classification guide with options “Definite/Highly Probable”, “Probable”, “Probably Not/No”, or “Unknown” for having asthma. Two specialists independently labeled records for each adult and disagreements were addressed to reach consensus. We used inter-rater reliability to report classification consistency across specialists. The gold standard classification was compared to four commonly used EHR rules-based schema. Results: After initial chart review, 465 of 600 records had consistent classifications, indicating moderate inter-rater reliability (κ-coefficient=0.66). Following attempted consensus, 593 of 600 records had consistent classifications (κ-coefficient=0.98). The final classification for the 7 remaining disagreements was adjudicated by a third physician. Presence of an asthma ICD-10 code and SABA prescription yielded the greatest consistency with asthma specialist chart review, with 68% of those records having the “Definite/Highly Probable” classification. When aggregating “Definite/Highly Probable” and “Probable” labels together, 89% of records were consistent. Using the asthma ICD-10 code plus SABA and ICS prescriptions yielded similarly high consistency. However, the number of records available when requiring presence of SABA or ICS prescription decreased to a third, suggesting that for some studies, a less strict definition may be preferable. Conclusion: Studies that rely on rules to classify asthma status based on EHR data are inherently limited, partly due to the difficulty of classifying adults with asthma according to information available. However, reasonable consistency between our gold standard classifications and rules-based algorithms provides supporting evidence of using EHR data to understand asthma outcomes with real-world data.

  PublisherDOI

• Guideline adherence to aeroallergen-focused activities in adult asthma care: Insights from an online survey

  Journal of Allergy and Clinical Immunology · 2025-10-10

  letterOpen access
  PublisherOA PDFDOI

• Impact of the COVID-19 Pandemic on Asthma-Related Healthcare Use in Adults

  American Journal of Respiratory and Critical Care Medicine · 2025-05-01

  article

  Abstract RATIONALE: While asthma exacerbation rates were observed to modestly decline during the COVID-19 pandemic, other trends in asthma-related healthcare use are not well-studied. METHODS: We performed a retrospective cohort study of electronic health record data from Penn Medicine, a large, diverse health system in Philadelphia, from encounters dated 1/1/2017-12/31/2023. We obtained patient-level data (e.g., gender and race) for adults with a diagnosis code for asthma linked to any qualifying encounter: medication refill, telephone, outpatient, telemedicine, or emergency department (ED). We identified short-acting beta agonist (SABA), inhaled corticosteroid (ICS), and oral corticosteroid (OCS) prescriptions. To evaluate changes during the pandemic, we summed counts for each encounter and prescription type for each week of the calendar year 2020 and compared counts in relation to week 12, representing the 3/17/2020 lockdown date in Philadelphia. To compare patients in 2020 to earlier and later years, we noted the peri-lockdown period in which changes in a count occurred, identified patients who comprised these counts, and compared their demographic characteristics to patients with the same counts in 2017-2019 and 2021-2023 using chi-squared tests. We further evaluated these differences while considering outpatient encounters in Primary Care, Allergy/Immunology, or Pulmonary. RESULTS: 88,195 adults with asthma had a qualifying encounter. Weeks 9-12 in 2020 showed increases in medication refill and telephone encounters, and of SABA and ICS prescriptions, for which each then declined to approximate their counts from weeks 1-8. Telemedicine encounter counts had a similar increase over the same period but did not subsequently decline to baseline. By contrast, outpatient encounter counts declined across weeks 9-12 and remained lower than the counts from weeks 1-8 for the remainder of 2020; and ED encounters and OCS prescription counts had more modest declines after the lockdown. A total of 17,611 patients had an outpatient encounter during weeks 9-12 of any calendar year, and comparing these patients across years did not reveal differences by gender (p>0.9) or race (p=0.09 across 6 categories). However, among 983/17,611 (5.6%) patients with an Allergy/Immunology encounter, the proportion of Black patients increased after 2017-2019 and remained elevated through 2021-2023 (p=0.007). CONCLUSION: Counts of most encounter types and of inhaler prescriptions increased in the peri-lockdown period but then declined, perhaps due to the “stockpiling” effect of essential supplies at the onset of the pandemic. Unexpectedly, we observed a racial difference in patients with Allergy/Immunology outpatient visits during and after the pandemic compared to prior.

  PublisherDOI

• Impact of the COVID-19 Pandemic on Adult Asthma-Related Healthcare Utilization

  medRxiv · 2025-09-21

  preprintOpen access

  BACKGROUND: The COVID-19 pandemic prompted unprecedented changes to chronic disease self-management and healthcare systems worldwide, including shifts in access to services and medications. While children with asthma had decreased exacerbations and healthcare encounters during 2020, the impact of lockdowns on adults with asthma, who faced different challenges during the pandemic than children, are less understood. OBJECTIVE: We sought to characterize changes in adult asthma-related healthcare utilization during the COVID-19 pandemic in 2020 versus prior (2017-2019) and subsequent (2021-2024) years by leveraging electronic health record (EHR) data from a large, multi-hospital health system in a major US city. METHODS: We conducted a retrospective EHR database study of 42,242 adults with asthma who received care at Penn Medicine from 2017 to 2024. We analyzed weekly encounter counts across five encounter types (refill, telemedicine, telephone/audio, outpatient, emergency encounters) and prescriptions for short-acting beta agonists (SABA), inhaled corticosteroids (ICS), and oral corticosteroids (OCS). Generalized linear models assessed changes in asthma-related encounter rate in pandemic (2020) and post-pandemic (2021-2024) periods relative to pre-pandemic (2017-2019). We stratified on weekly intervals that captured transitional timepoints in healthcare utilization in 2020 (Weeks 1-8, 9-18, and 19-52). RESULTS: In 2017-2019, there were on average 397 weekly visits for asthma at Penn Medicine; in 2020, the weekly average increased to 481. This change was driven primarily by a surge during the lockdown weeks in refill and telemedicine encounters by 123% and 36,445%, respectively and by a decrease in outpatient visits by 65%. During the lockdown weeks in 2020, asthma related prescriptions of SABA and ICS prescriptions increased 73% and 43%, respectively, compared to pre-pandemic years, while OCS prescriptions decreased by 5%. White patients showed earlier healthcare-seeking responses than other racial groups. Changes persisted in post-pandemic years as the average of weekly asthma-related visits was 445 in 2021-2024. Telemedicine remained 38-76 times higher than pre-pandemic baseline, refills doubled compared to 2017-2019 levels, and outpatient visits remained 35-43% below pre-pandemic levels. CONCLUSION: COVID-19 transformed adult asthma care delivery and led to sustained increases in virtual care and medication refills potentially due to virtual care compensating for reductions in traditional outpatient encounters.

  PublisherOA PDFDOI

• Maintenance of an Asthma Intervention Post-Trial: Use of a Patient-Activated Reliever-Triggered Inhaled Corticosteroid (PARTICS) Strategy in Black and Latinx Patients

  The Journal of the American Board of Family Medicine · 2025-03-01

  articleOpen access

  PURPOSE: A Patient-Activated Reliever-Triggered Inhaled Corticosteroid (PARTICS) strategy of enhancing usual care with rescue short-acting beta agonist (SABA) supplemented with inhaled corticosteroid (ICS) reduces asthma exacerbations vs. usual care alone in Black and Latinx adults with moderate-severe asthma. We investigated post-trial PARTICS usage and patient perceptions of efficacy. METHODS: PREPARE trial participants randomized to the PARTICS intervention were surveyed an average of 29 months after trial exit. RESULTS: Of 600 PARTICS-assigned PREPARE trial participants, 505 consented to future research. Fifty-two percent (262/505) completed this survey. Forty-one percent (108/262) continued using PARTICS post-trial. Of these, 97% (105/108) reported that PARTICS helped to control their asthma. Thirty-four percent (37/108) switched from the trial provided QVAR® to other ICS brands due to insurance coverage or clinician issues (e.g., unwillingness to prescribe or misunderstanding of PARTICS; 65%, 24/37). Of those who stopped using PARTICS post-trial (59% [154/262]), 62% (95/154) reported using PARTICS until the PREPARE-provided ICS inhaler ran out, and 31% (47/154) reported not knowing that their asthma care clinician could prescribe it. Only 2% (5/154) of those not using PARTICS reported that it had not been helpful for asthma. CONCLUSIONS: Continued PARTICS use was common >2 years post-trial despite minimal study instruction and was perceived as helpful for asthma, suggesting that patients will likely adopt this strategy if implemented at a healthcare system level.

  PublisherOA PDFDOI

• Recurrent Preschool Wheeze: The Impact of Adverse Social Drivers of Health and Opportunities for Interventions

  The Journal of Allergy and Clinical Immunology In Practice · 2025-07-05 · 2 citations

  articleOpen access
  PublisherOA PDFDOI

• Augmenting electronic health record data with social and environmental determinant of health measures to understand regional factors associated with asthma exacerbations

  PLOS Digital Health · 2025-06-23 · 1 citations

  articleOpen access

  Electronic health records (EHRs) provide rich data for diverse populations but often lack information on social and environmental determinants of health (SEDH) that are important for the study of complex conditions such as asthma, a chronic inflammatory lung disease. We integrated EHR data with seven SEDH datasets to conduct a retrospective cohort study of 6,656 adults with asthma. Using Penn Medicine encounter data from January 1, 2017 to December 31, 2020, we identified individual-level and spatially-varying factors associated with asthma exacerbations. Black race and prescription of an inhaled corticosteroid were strong risk factors for asthma exacerbations according to a logistic regression model of individual-level risk. A spatial generalized additive model (GAM) identified a hotspot of increased exacerbation risk (mean OR = 1.41, SD 0.14, p < 0.001), and inclusion of EHR-derived variables in the model attenuated the spatial variance in exacerbation odds by 34.0%, while additionally adjusting for the SEDH variables attenuated the spatial variance in exacerbation odds by 66.9%. Additional spatial GAMs adjusted one variable at a time revealed that neighborhood deprivation (OR = 1.05, 95% CI: 1.03, 1.07), Black race (OR = 1.66, 95% CI: 1.44, 1.91), and Medicaid health insurance (OR = 1.30, 95% CI: 1.15, 1.46) contributed most to the spatial variation in exacerbation odds. In spatial GAMs stratified by race, adjusting for neighborhood deprivation and health insurance type did not change the spatial distribution of exacerbation odds. Thus, while some EHR-derived and SEDH variables explained a large proportion of the spatial variance in asthma exacerbations across Philadelphia, a more detailed understanding of SEDH variables that vary by race is necessary to address asthma disparities. More broadly, our findings demonstrate how integration of information on SEDH with EHR data can improve understanding of the combination of risk factors that contribute to complex diseases.

  PublisherDOI

• Semi-parametric sensitivity analysis for trials with irregular and informative assessment times

  Biometrics · 2024-10-03 · 3 citations

  articleOpen access

  Many trials are designed to collect outcomes at or around pre-specified times after randomization. If there is variability in the times when participants are actually assessed, this can pose a challenge to learning the effect of treatment, since not all participants have outcome assessments at the times of interest. Furthermore, observed outcome values may not be representative of all participants' outcomes at a given time. Methods have been developed that account for some types of such irregular and informative assessment times; however, since these methods rely on untestable assumptions, sensitivity analyses are needed. We develop a sensitivity analysis methodology that is benchmarked at the explainable assessment (EA) assumption, under which assessment and outcomes at each time are related only through data collected prior to that time. Our method uses an exponential tilting assumption, governed by a sensitivity analysis parameter, that posits deviations from the EA assumption. Our inferential strategy is based on a new influence function-based, augmented inverse intensity-weighted estimator. Our approach allows for flexible semiparametric modeling of the observed data, which is separated from specification of the sensitivity parameter. We apply our method to a randomized trial of low-income individuals with uncontrolled asthma, and we illustrate implementation of our estimation procedure in detail.

  PublisherOA PDFDOI

• Improving Adherence Through Collaboration and Care Coordination in the Management of Food Allergies and Asthma

  The Journal of Allergy and Clinical Immunology In Practice · 2024-09-14 · 3 citations

  review
  PublisherDOI

Recent grants

• NIH Grant RC1HL099612

  NIH · $1.0M · 2012

• NIH Grant K02HL088469

  NIH · $526k · 2012

• NIH Grant R18HL116285

  NIH · $3.6M · 2021

• NIH Grant R01HL073932

  NIH · $3.6M · 2011

• NIH Grant K23HL004337

  NIH · $651k · 2006

Frequent coauthors

• Tyra Bryant-Stephens

  University of Pennsylvania

  35 shared

• Warren B. Bilker

  University of Pennsylvania

  22 shared

• Brian L. Strom

  Rutgers, The State University of New Jersey

  21 shared

• David J. Margolis

  University of Pennsylvania

  20 shared

• Sean Hennessy

  University of Pennsylvania

  17 shared

• Knashawn H. Morales

  University of California, Davis

  17 shared

• Luzmercy Perez

  Stanford University

  16 shared

• R. H. Kobayashi

  16 shared