Epic Research

Fentanyl Testing Associated with Short-Term Survival Benefits; Increased Long-Term Mortality Risk Among Overdose Patients

Thu, 26 Feb 2026 12:00:00 +0000

Opioid misuse continues to pose a critical public health issue in the United States, particularly due to the increasing prevalence of synthetic opioids such as fentanyl.¹ Efforts to curb this epidemic have been implemented, such as increased fentanyl screening and increasing access to naloxone².However, questions remain about whether fentanyl testing during ED encounters is associated with subsequent treatment and survival.

To understand trends in overdose visits, we studied more than 230 million ED visits between January 2018 and November 2025. We studied overall overdoses, overdoses from opioids, and overdoses from synthetic opioids, each a subset of the preceding broader category.

The 12-month rolling average rate of ED visits for all types of overdoses peaked at 946 per 100,000 in March 2021, a period when overall ED volumes were unusually low, as seen in Figure 1.³ By November 2025, the rate had declined to 634 per 100,000, reflecting a 33% decline and falling below pre-pandemic levels. Opioid overdoses followed a similar trajectory, with rates trending downward after naloxone became available over the counter in 2023.² In contrast, synthetic opioid overdoses increased more than threefold from 15 to 51 per 100,000 visits between December 2018 and November 2025, though rates have declined after peaking at 66 per 100,000 in December 2023. Notably, testing for synthetic opioids also increased by more than 400% from the first quarter of 2021 to the fourth quarter of 2025, as seen on the Epic Research Fentanyl and Opiate Toxicology data tracker.⁴

Figure 1. The 12-month rolling average rate of ED visits for any overdose, opioid overdose, and synthetic opioid overdose.

There has been a rise in the incidence of synthetic opioid overdose mortality cases since 2018,⁵ picking up in 2020 and reaching a peak of 77,695 cases in June 2023, according to the U.S. Centers for Disease Control and Prevention (CDC), as seen in Figure 2. Since then, the number of synthetic opioid overdose deaths has declined substantially, reaching a low of 38,514 cases in August 2025, a reduction of more than 50% from the peak.

Figure 2. The rate of synthetic opioid overdose deaths for the previous 12 months based on data from the CDC.

To understand the relationship between fentanyl testing and outcomes such as mortality and repeat overdose encounters, we studied more than 1 million patients who had a non-fatal ED visit for an overdose. We accounted for demographics, social vulnerability and rurality based on most recently documented address, count of prior overdose encounters, administration of naloxone during the ED visit, and ED acuity score.

Among patients who were tested for fentanyl, the likelihood of being prescribed a medication for opioid use disorder (MOUD) during the encounter was 147% higher compared to those who were not tested for fentanyl, as seen in Figure 3. Short term outcomes were also improved: the likelihood of death within 30 days was 11% lower. There was not a significant difference in the likelihood of a repeat ED visit for an overdose within 30 days between patients who had fentanyl testing and those who did not. The likelihood of mortality or a repeat overdose within one year was higher among those who had fentanyl testing than those who were not tested. This pattern might reflect that patients who receive fentanyl testing represent a higher-risk population with more severe substance use disorders.

Figure 3. The likelihood of mortality, subsequent overdose, or MOUD treatment by whether the patient was tested for fentanyl during an overdose encounter.

Importantly, fentanyl testing might indicate clinical suspicion or resource availability. Indications for testing patients for fentanyl might include additional considerations we were not able to fully assess as part of this analysis.

These data come from Cosmos, a dataset created in collaboration with a community of Epic health systems representing more than 300 million patient records from 1,900 hospitals and more than 42,000 clinics from all 50 U.S. states, Lebanon, and Saudi Arabia. This study was completed by two teams that worked independently, each composed of a clinician and research scientists. The two teams came to similar conclusions. Graphics by Brian Olson.

Pickens CM, Park J, Casillas SM, et al. Trends in Suspected Fentanyl-Involved Nonfatal Overdose Emergency Department Visits, by Age Group, Sex, and Race and Ethnicity – United States, October 2020-March 2024. MMWR Morb Mortal Wkly Rep. 2025;74(16):282-287. Published 2025 May 8. doi:10.15585/mmwr.mm7416a2
Emergent BioSolutions’ NARCAN® Nasal Spray Launches Over the Counter Making it Possible for Everyone to Help Save a Life from an Opioid Overdose Emergency. Emergent BioSolutions. August 30, 2023. https://investors.emergentbiosolutions.com/news-releases/news-release-details/emergent-biosolutions-narcanr-nasal-spray-launches-over-counter. Accessed January 12, 2026.
Noel A, Alban C, Trinkl J et al. Fewer Visits, Sicker Patients: The Changing Character of Emergency Department Visits During the COVID-19 Pandemic. Epic Research. https://epicresearch.org/articles/fewer-visits-sicker-patients-the-changing-character-of-emergency-department-visits-during-the-covid-19-pandemic. Accessed on August 11, 2025.
Fentanyl and Opiate Toxicology in Emergency Department Overdoses. Epic Research. https://www.epicresearch.org/data-tracker/fentanyl-and-opiate-toxicology. Accessed August 26, 2025.
Ahmad FB, Cisewski JA, Rossen LM, Sutton P. Provisional drug overdose death counts. National Center for Health Statistics. 2025. DOI: https://dx.doi.org/10.15620/cdc/20250305008

Influenza Visits Peak Higher This Season, Especially Among Children and Older Adults

Taylor Kirby — Tue, 24 Feb 2026 13:45:00 +0000

Seasonal influenza places a significant burden on healthcare systems each year, and the timing, intensity, and age distribution of flu seasons can vary considerably.¹ Understanding how influenza affects different age groups helps inform vaccination campaigns, clinical preparedness, and public health messaging.

To increase understanding of age-group-specific trends in influenza and other communicable diseases, we updated the Communicable Diseases Data Tracker to include age group breakdowns: under 2, 2–4, 5–17, 18–49, 50–64, and 65 and older. The data tracker shows weekly rates of communicable disease diagnoses or positive labs per 100,000 patients with office visits, emergency department visits, or admissions across more than 300 healthcare organizations.

This season’s influenza peak was notably higher than the prior two seasons, but the increase was not evenly distributed across age groups. Children and older adults saw the sharpest rise, while middle-aged adults were largely unaffected. Among all age groups, children experienced the highest peak visit rates, rising to 90% higher than the 2023–24 season. Adults aged 65 and older also saw a marked increase, with peak rates 56% above the 2023–24 season. By contrast, adults aged 50–64 showed virtually no change across all three seasons, and adults aged 18–49 saw only a moderate increase.

Figure 1. Peak influenza visit rates per 100,000 patients by age group since the 2023–24 flu season.

Hu T, Miles AC, Pond T, et al. Economic burden and secondary complications of influenza-related hospitalization among adults in the US: a retrospective cohort study. J Med Econ. 2024;27(1):324-336. doi:10.1080/13696998.2024.2314429

“Lean MASLD” Typically Clustered Near Obese BMI Threshold

Kersten Bartelt, RN; Eric Barkley; Louis Kazaglis, MD; Jacob Gasser — Thu, 19 Feb 2026 12:00:00 +0000

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease, is the most common chronic liver disease worldwide, affecting an estimated one in four U.S. adults.¹ Although MASLD is closely associated with obesity, the disease also occurs in individuals without obesity, a phenomenon known as “lean MASLD”.²

To better understand factors that influence MASLD, particularly those at non-obese BMIs, we studied 190,335 patients diagnosed with MASLD between ages 45 and 64 who did not have hepatitis, alcohol-related disorders, amputations, or tamoxifen exposure. Patients were categorized into six BMI groups based on their BMI measurement in the year prior to their diagnosis: underweight (<18.5), healthy weight (18.5–24.9), overweight-low (25.0–27.4), overweight-high (27.5–29.9), class 1—2 obesity (30.0–39.9), and class 3 obesity (40+).

We found that most patients diagnosed with MASLD (79.1%) had an obese BMI. Among non-obese patients, MASLD was most common in the overweight range and least common in underweight and healthy weight categories. This pattern suggests that excess weight is a risk factor for MASLD even among patients who are not clinically obese.

Figure 1. The BMI distribution among non-obese patients aged 45–64 with MASLD

While BMI is a primary risk factor in the development of MASLD, we examined whether additional conditions were correlated with MASLD. Circulatory disorders increased substantially from underweight to severe obesity (47.5% to 81.9%), and endocrine disorders were highly prevalent across all BMI groups and increased further with an increase in BMI (79.2% to 95.6%), consistent with a growing cardiometabolic burden as BMI rises among patients with MASLD.

In contrast, underweight patients exhibited a distinct profile, including the highest rates of blood disorders (41.7%), which suggests this subgroup might differ meaningfully from higher-BMI MASLD patients and might warrant closer attention to other factors.

Figure 2. The prevalence of condition groups among patients aged 45–64 with MASLD by their BMI classification.

These data come from Cosmos, a dataset created in collaboration with a community of Epic health systems representing more than 300 million patient records from 1,800 hospitals and more than 42,000 clinics from all 50 U.S. states, Canada, Lebanon, and Saudi Arabia. This study was completed by two teams that worked independently, each composed of a clinician and research scientists. The two teams came to similar conclusions. Graphics by Brian Olson.

Sheth SG, Chopra S. Clinical features and diagnosis of metabolic dysfunction-associated steatotic liver disease (nonalcoholic fatty liver disease) in adults. UpToDate. March 7, 2025. https://www.uptodate.com/contents/clinical-features-and-diagnosis-of-metabolic-dysfunction-associated-steatotic-liver-disease-nonalcoholic-fatty-liver-disease-in-adults. Accessed August 27, 2025.
Rotaru A, Stratina E, Huiban L, et al. Beyond BMI: revealing metabolic risk in lean MASLD. Arch Clin Cases. 2025;12(3):110-118. Published 2025 Aug 4. doi:10.22551/2025.48.1203.10322

Telehealth Use for Primary Care Visits Has Stabilized, with Higher Use in Metropolitan Areas and Among Non-English Speakers

Kersten Bartelt, RN; Emily Higgs ; Louis Kazaglis, MD; Eric Barkley — Tue, 17 Feb 2026 12:00:00 +0000

Telehealth use in the United States expanded rapidly during the COVID-19 pandemic, supported by temporary federal and commercial coverage flexibilities that allowed virtual care to substitute for in-person visits across primary care and many specialties.¹ Since then, telehealth use has declined across all specialties,² with mental health care retaining the highest proportion of visits conducted by telehealth.³ Policy discussions now focus on which flexibilities should be made permanent and how telehealth affects access and equity, particularly across different populations.⁴ Understanding how telehealth has trended in the post-acute pandemic period and how patterns differ by geography, age, and preferred language can inform operational planning, interpreter services, and policy decisions.

We studied 411 million primary care visits between July 2022 and October 2025. For each encounter, we identified the patient’s rurality based on their most recent ZIP Code, their age at the time of the encounter, and their preferred language. We evaluated each subgroup for the proportion of primary care they had conducted by telehealth.

Across all primary care encounters, telehealth use declined from mid-2022 to mid-2023 and then stabilized at around 6% of visits. Telehealth accounted for just over 8% of encounters in July 2022 and just under 6% by October 2025, representing a roughly 30% reduction by the end of the study period. Since 2023, the overall telehealth share has remained around 6–7%, suggesting a new steady state in the balance between virtual and in-person care.

Telehealth remained more common for patients from metropolitan areas than for those from less urban settings throughout the study period, as seen in Figure 1. While the telehealth proportion fell in all rurality categories, the relative urban–rural gradient persisted: metropolitan patients consistently had about twice the telehealth rate of patients in rural or small-town areas, with micropolitan areas in between.

Figure 1. The 12-month rolling average percent of primary care visits that were conducted using telehealth by patient’s rurality.

Age patterns were stable over time, with telehealth concentrated among working-age adults and less frequently used for very young children and the oldest adults. Children aged 0–2 years consistently had telehealth shares below 2%, while adults aged 25–39 years had rates above 10% across the study window.

Figure 2. The 12-month rolling average percent of visits in primary care that were conducted using telehealth by patient’s age.

Telehealth use was consistently higher among patients whose preferred language was not English, and this pattern persisted despite overall declines, as seen in Figure 3. Chinese-, Portuguese-, Russian-, Persian-, and Spanish-speaking patients started from substantially higher baseline telehealth rates, and those rates remained substantially higher than those of English speakers by the end of the study period.

Figure 3. The 12-month rolling average percent of primary care visits that were conducted using telehealth by patient’s preferred language.

Shaver J. The State of Telehealth Before and After the COVID-19 Pandemic. Prim Care. 2022;49(4):517-530. doi:10.1016/j.pop.2022.04.002
Bartelt K, Piff A, Allen S, Barkley E. Telehealth Utilization Higher Than Pre-Pandemic Levels, but Down from Pandemic Highs. Epic Research. https://epicresearch.org/articles/telehealth-utilization-higher-than-pre-pandemic-levels-but-down-from-pandemic-highs. Accessed on December 17, 2025.
Telehealth Utilization. Epic Research. https://www.epicresearch.org/data-tracker/telehealth-trending. Accessed December 17, 2025.
Telehealth policy updates. Health Resources & Services Administration. November 21, 2025. https://telehealth.hhs.gov/providers/telehealth-policy/telehealth-policy-updates. Accessed on December 17, 2025.

Prostate Cancer Screening and Diagnosis Rates Up for 55–84-Year-Old Men

Taylor Kirby — Thu, 12 Feb 2026 12:00:00 +0000

Prostate cancer is the second most common cancer among men in the United States and is most common in older men.¹ Prostate-specific antigen (PSA) blood testing can be used as a screening tool to identify patients at high risk of developing prostate cancer.²However, PSA-based screening is not standardly recommended for all men: the U.S. Preventive Services Task Force (USPSTF) recommends shared clinical decision-making between a physician and the patient to determine whether PSA screening should be performed.³

Our Epic Research Cancer Incidence Data Tracker tracks the rate of new prostate cancer diagnoses and PSA screenings each quarter over the past four years. The rates are stratified by age to better understand trends across different demographic groups.

Quarterly PSA screening rates increased across all age groups assessed between Q1 2021 and Q4 2025. Screening among men ages 55–64 increased the most over this period, increasing nearly 50% from 6,497.3 screenings per 100,000 encounters to 9,696.0 screenings per 100,000 encounters.

Figure 1. PSA prostate cancer screening rates by quarter from 2021 to 2025.

Over the same period, the rate of new prostate cancer diagnoses increased for men aged 55–64, 65–74, and 75–84, whose rate of new prostate cancer diagnoses increased 22%, 15%, and 12%, respectively.

Figure 2. New prostate cancer diagnosis rates by quarter from 2021 to 2025.

You can stay up to date on the latest trends in cancer diagnoses and screenings with our Epic Research data tracker.

American Cancer Society. Key Statistics for Prostate Cancer | Prostate Cancer Facts. www.cancer.org. Published January 19, 2024. https://www.cancer.org/cancer/types/prostate-cancer/about/key-statistics.html
‌American Cancer Society. Prostate cancer screening tests. www.cancer.org. Published 2023. https://www.cancer.org/cancer/types/prostate-cancer/detection-diagnosis-staging/tests.html
‌ USPSTF. Recommendation: Prostate Cancer: Screening | United States Preventive Services Taskforce. www.uspreventiveservicestaskforce.org. Published 2018. https://www.uspreventiveservicestaskforce.org/uspstf/recommendation/prostate-cancer-screening

Adding or Switching Diuretics Is Associated with Fewer CHF Exacerbations Than Increasing Dose or Frequency

Kersten Bartelt, RN; Grant Keane ; Tom Elliott, MPharm GPhC; Joe Deckert, PhD — Tue, 10 Feb 2026 12:00:00 +0000

Congestive heart failure (CHF) is a leading cause of emergency department visits and hospital admissions in the United States, with exacerbations driving substantial morbidity, mortality, and healthcare utilization.¹ Diuretics are a cornerstone of symptom management in patients with volume overload (which commonly occurs among patients with CHF), yet many patients experience persistent or worsening symptoms despite ongoing therapy.² When diuretic response is inadequate, clinicians commonly escalate treatment by increasing dose, increasing dosing frequency, changing diuretic class, or combining diuretics. While these strategies are widely used, comparative evidence on which escalation pathways are associated with better short-term outcomes is limited. Understanding how these common decisions relate to downstream exacerbations could help clinicians choose escalation strategies that minimize acute care utilization.

We studied 245,738 patients with CHF between January 2017 and October 2025 who had their first prescription for a loop diuretic, aldosterone antagonist diuretic, or low-ceiling diuretic. Patients were identified by their diuretic escalation event, categorized as an increase in medication dose, an increase in medication frequency, an increase in both dose and frequency, or a change to or addition of another diuretic type. When evaluating outcomes, we accounted for patient demographics, rurality and social vulnerability based on residence, BMI classification, prior ED utilization, duration on diuretic therapy, prior IV diuretic use, history of chronic kidney disease, history of heart failure, prior CHF exacerbations, and care setting type for the initial diuretic prescription.

Across outcomes, escalation strategies that increased diuretic frequency were consistently associated with worse short-term CHF outcomes compared to increasing dosage. Increasing diuretic frequency alone was associated with a 43–46% higher likelihood of CHF exacerbations in both the ED and inpatient settings compared to increasing dosage alone. Increasing both dose and frequency was associated with even larger increases (a 52–60% higher likelihood of exacerbation-related admission) compared to increasing the dosage alone. In contrast, modifying the diuretic regimen appeared more favorable. Adding an additional diuretic was associated with a 13% lower likelihood of ED visits for CHF exacerbations and a 7% lower likelihood of an admission for exacerbations compared with dose increases alone. Switching diuretic classes was also associated with a 12% lower likelihood of ED visits for exacerbations, though the association with admissions for exacerbations was small and not statistically significant.

Figure 1. The likelihood of an ED visit or admission for CHF exacerbation by the diuretic escalation event the patient experienced.

Together, these patterns suggest that addressing inadequate response through combination or alternative diuretic therapy may be associated with fewer short-term exacerbations than strategies focused solely on intensifying dose or frequency.

Heidenreich PA, Bozkurt B, Aguilar D, et al. 2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure: Executive Summary: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Circulation. 2022;145(18):e876-e894. doi:10.1161/CIR.0000000000001062
Colucci WS, Vader JM. Heart failure: Management of acute decompensation and volume overload. UpToDate. January 27, 2026. https://www.uptodate.com/contents/heart-failure-management-of-acute-decompensation-and-volume-overload. Accessed February 9, 2026.

Telehealth and In-Person Follow-Up for New Blood Pressure Treatments Show Similar Outcomes

Kersten Bartelt, RN; Ted Stamp ; Tony Dunnigan, MD; Grant Keane — Thu, 29 Jan 2026 15:00:00 +0000

Telehealth has become a routine component of outpatient follow-up care. For patients newly diagnosed with hypertension, early follow-up after medication initiation is critical for adjustment and blood pressure control.¹ Some researchers have raised concerns that telehealth visits may result in fewer documented blood pressure measurements and less frequent medication intensification compared with in-person care,² though trials have generally not found telehealth to be inferior for hypertension management.³ Evaluating short-term systolic blood pressure trends can help determine whether greater reliance on telehealth compromises early hypertension management or performs similarly to traditional face-to-face care.

We studied 24,325 adults aged 18 years or older in the U.S. who were newly diagnosed with hypertension and received their first antihypertensive medication prescription between January 1, 2021, and November 1, 2025. Telehealth engagement was defined as the proportion of outpatient encounters conducted by telehealth categorized as 0%, 1–24%, 25–49%, or 50–74% after the antihypertensive was ordered. There were too few patients who had 75% or more of their follow-up visits via telehealth to include that group in this analysis. We accounted for baseline systolic blood pressure category, demographics, rurality and social vulnerability based on residence, smoking history, antihypertensive class, and comorbidities (including diabetes, hyperlipidemia, cardiovascular disease, and prior major adverse cardiovascular events).

We found that greater use of telehealth for follow-up care was not associated with better or worse short-term systolic blood pressure readings after initiation of antihypertensive medication. Compared with patients who had no telehealth visits, those with higher telehealth engagement had similar systolic blood pressure levels across most of the 12-week follow-up period. Differences between telehealth groups were small, and many weekly comparisons were not statistically significant.

Figure 1. The weekly adjusted systolic blood pressure of patients following initiation of antihypertensives by the proportion of their visits conducted by telehealth.

Overall, the results suggest that telehealth-dominant follow-up care performs comparably to in-person care for early blood pressure control.

Whelton PK, Carey RM. The 2017 Clinical Practice Guideline for High Blood Pressure. JAMA. 2017;318(21):2073-2074. doi:10.1001/jama.2017.18209
Clinical case study: Telehealth for hypertension. American Medical Association. July 16, 2021. https://www.ama-assn.org/public-health/prevention-wellness/clinical-case-study-telehealth-hypertension. Accessed December 29, 2025.
Omboni S, McManus RJ, Bosworth HB, et al. Evidence and Recommendations on the Use of Telemedicine for the Management of Arterial Hypertension: An International Expert Position Paper. Hypertension. 2020;76(5):1368-1383. doi:10.1161/HYPERTENSIONAHA.120.15873

ED Visits for Motor Vehicle Crashes Associated with Elevated Risk of Subsequent Firearm Injury for Young Male Patients

Thu, 15 Jan 2026 19:30:00 +0000

Motor vehicle crashes (MVCs) and firearm injuries are two major contributors to injury-related morbidity in the United States.¹ Prior clinical and public health research has shown that patterns of traumatic injury, risk-taking behavior, and exposure to violence frequently cluster in adolescence and early adulthood.^1,2 While both MVCs and firearm injuries disproportionately affect adolescents and young adults, limited evidence exists on whether an ED presentation for one type of traumatic exposure may identify patients at elevated risk for another. Identifying ED-based markers of elevated future risk could inform targeted prevention strategies, resource allocation, and community-based violence-intervention programs. We aimed to understand the relationship between ED visits for MVCs and the likelihood of future firearm injury.

We studied more than 2 million U.S. patients with an ED visit for an MVC and another 2 million U.S. patients with an ED visit for a fall between 2017 and November 11, 2025. Patients were excluded if they had a documented history of firearm injury, MVC, or fall before the ED visit of interest. Patients with an ED visit for an MVC were matched with patients whose ED visit was for a fall based on age, sex, race and ethnicity, census region, and month of the ED encounter. We additionally accounted for rurality based on residence, social vulnerability based on residence, ED acuity score, smoking history, prior health care utilization, and history of comorbidities including mental health conditions, traumatic brain injury, pervasive developmental disorders, and lead poisoning.

Across most census regions, male patients aged 10 to 15 experienced the clearest pattern of elevated firearm-injury risk following an ED visit for an MVC, with as much as four times as likely as those whose ED visit was for a fall, as seen in Figure 1. For male patients aged 16 to 25, the association persisted across many census regions but was smaller in magnitude; depending on region, patients were 81% more likely to have a firearm injury following an MVC compared to a fall.

Figure 1. The risk of a firearm injury following an ED visit for an MVC compared to after a fall among males by age and geographic region.

Of note, significance was not observed for female patients or adults over age 25 in nearly all stratifications.

These data come from Cosmos, a dataset created in collaboration with a community of Epic health systems representing more than 300 million patient records from 1,800 hospitals and more than 41,000 clinics from all 50 U.S. states, Canada, Lebanon, and Saudi Arabia. This study was completed by two teams that worked independently, each composed of a clinician and research scientists, in collaboration with researchers from Children’s Wisconsin. The two teams came to similar conclusions. Graphics by Brian Olson.

Cunningham RM, Walton MA, Carter PM. The major causes of death in children and adolescents in the United States. N Engl J Med. 2018;379(25):2468-2475. doi:10.1056/NEJMsr1804754
Sims DW, Bivins BA, Obeid FN, Horst HM, Sorensen VJ, Fath JJ. Urban trauma: a chronic recurrent disease. J Trauma. 1989;29(7):940-947.

Low Body Temperature Among 5- to 8-Week-Old Infants Is a Modest Predictor of Bacterial Infections

Tue, 06 Jan 2026 12:00:00 +0000

Hypothermia, or low body temperature, is concerning in infants, and there are a number of potential causes. It can be difficult to determine if the low temperature is due to inadequate temperature regulation, environmental exposure, or an underlying bacterial infection.¹ The strength of low temperature’s association with true bacterial illness has remained uncertain in previous literature.^2,3 Understanding whether low temperature meaningfully predicts bacterial infection, especially in relation to key developmental age groups, is important for informing evaluation pathways and avoiding unnecessary testing.

We studied 128,979 U.S. infants younger than 8 weeks old who had an emergency department (ED) visit between January 1, 2017, and September 30, 2025, and who had a blood, cerebrospinal fluid, or urine culture performed; a documented temperature during the visit; and a birth record in Cosmos. Infants were classified as having a low temperature (<36°C), normal temperature (36–38°C), or elevated temperature (>38°C) based on the lowest or highest temperature recorded during the visit. We then looked for an abnormal blood, cerebrospinal fluid, or urine culture as confirmation of a bacterial infection. Infants were grouped into those who were born prematurely (<37 weeks) or who had a NICU stay near the time of birth and those who were full term without a NICU stay. We accounted for social vulnerability based on residence, rurality based on residence, demographics, ED acuity level, census region of residence, and age group (birth to 3 weeks, 4 weeks, 5 to 8 weeks). Clinical guidelines for managing newborns with an abnormal temperature vary based on the infant’s age.⁴

Across all age groups, elevated temperature was a strong predictor of bacterial infection, whereas low temperature demonstrated an age-dependent pattern, as shown in Figure 1. Among 5- to 8-week-old infants, those with a low temperature were 42% more likely to have a bacterial infection if they were full term without a NICU stay and 53% more likely if they were preterm or had a NICU stay, compared with infants who had a normal temperature. Among 4-week-old infants, low temperature was not associated with a significant change in infection likelihood in either group. Among the youngest infants (birth to 3 weeks old), there was no clinically meaningful increase in infection likelihood with low temperature, which was associated with only a 9% increase in likelihood for full term infants without a NICU stay and a statistically insignificant increase for infants who were premature or had a NICU stay.

Figure 1. The likelihood of an infant having a bacterial infection by their age, whether they were preterm or had a NICU stay, and their body temperature.

These findings suggest that low body temperature might be a meaningful predictor of bacterial infections for infants starting at 5 weeks old.

These data come from Cosmos, a dataset created in collaboration with a community of Epic health systems representing more than 300 million patient records from 1,800 hospitals and more than 41,000 clinics from all 50 U.S. states, Canada, Lebanon, and Saudi Arabia. This study was completed by two teams that worked independently, each composed of a clinician and research scientists, in collaboration with a researcher from UPMC Children’s Hospital of Pittsburgh. The two teams came to similar conclusions. Graphics by Brian Olson.

Ramgopal S, Lo YHJ, Potisek NM, Money NM, Halvorson EE, Cruz AT, Rogers AJ. Current Evidence on the Care of Young Infants With Hypothermia in the Emergency Department. Pediatr Emerg Care. 2025 Feb 1;41(2):146-151. doi: 10.1097/PEC.0000000000003259. PMID: 39883795.
Ramgopal S, Walker LW, Vitale MA, Nowalk AJ. Factors associated with serious bacterial infections in infants ≤60 days with hypothermia in the emergency department. Am J Emerg Med. 2019;37(6):1139-1143. doi:10.1016/j.ajem.2019.04.015
Ramgopal S, Noorbakhsh KA, Pruitt CM, Aronson PL, Alpern ER, Hickey RW. Outcomes of young infants with hypothermia evaluated in the emergency department. J Pediatr. 2020;221:132-137.e2. doi:10.1016/j.jpeds.2020.03.002
Fever in infants 0 to 60 days. Children’s Hospital Colorado. https://www.childrenscolorado.org/health-professionals/clinical-resources/clinical-pathways/fever-in-infants-0-to-60-days/. Accessed December 18, 2025.

Progestin-Only Birth Control Linked to Lower Likelihood of New Migraine Diagnoses

Kersten Bartelt, RN; Nicholas Volker ; Christopher Alban, MD; Grant Keane — Thu, 18 Dec 2025 19:00:00 +0000

Migraines affect many women of reproductive age, and hormone changes are known triggers. While clinical guidance often considers migraine history when prescribing estrogen-containing birth control,¹ much less is known about how hormonal contraception might influence the initial onset of migraines. Understanding whether progestin-only birth control affects the likelihood of newly being diagnosed with migraines provides important context for contraceptive counseling.

We studied more than 2 million patients aged 15 to 49. We matched patients newly diagnosed with migraines between January 1, 2018, and December 31, 2023, with patients who had an office visit in the same month and who were of similar age, race, ethnicity, and hypertension status. We also accounted for social vulnerability and rurality based on residence, BMI classification, smoking history, prior pregnancy, and census region in our analysis. We ended the study period at the end of 2023 because oral contraceptives became available over the counter in 2024,² reducing our ability to reliably identify users.

We found that patients who used intrauterine progestin-only birth control were 24% less likely to have migraines diagnosed within two years compared to patients without a history of birth control use, as seen in Figure 1. Similarly, patients who were on oral progestin-only birth control were 18% less likely to be diagnosed with migraines within two years, those who were on intramuscular progestin-only birth control were 15% less likely, and those on other routes were 13% less likely.

Figure 1. The likelihood of a novel migraine diagnosis in women prescribed progestin-only birth control by route.

Because this study included only individuals without prior migraines, the findings reflect association with new diagnoses rather than migraine progression.

These data come from Cosmos, a dataset created in collaboration with a community of Epic health systems representing more than 300 million patient records from 1,800 hospitals and more than 41,000 clinics from all 50 U.S. states, Canada, Lebanon, and Saudi Arabia. This study was completed by two teams that worked independently, each composed of a clinician and research scientists. The two teams came to similar conclusions. Graphics by Brian Olson.

MacGregor EA. Migraine and use of combined hormonal contraceptives: a clinical review. J Fam Plann Reprod Health Care. 2007;33(3):159-169. doi:10.1783/147118907781004750
FDA approves first nonprescription daily oral contraceptive. U.S. Food and Drug Administration. August 9, 2024. https://www.fda.gov/news-events/press-announcements/fda-approves-first-nonprescription-daily-oral-contraceptive. Accessed December 11, 2025.