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A pregnant patient’s body mass index (BMI) can affect the risk of complications for both the patient and the baby.1 We reviewed EHR data for more than 900,000 pregnancies that had pre-pregnancy BMI data to identify rates of certain delivery, prenatal, and postpartum complications.  Figure 1 shows rates of cesarean section, preterm delivery, and low birth weight. Rates of cesarean section increase steadily as maternal BMI increases, while rates of preterm delivery and […]

Many other healthcare settings have seen changes in the patient populations they see since the beginning of the COVID-19 pandemic. Prior to the pandemic, urgent care facilities were becoming popular alternatives to emergency departments for patients with urgent, but non-life-threatening, conditions. We wondered how the pandemic has impacted the volume and types of care sought in urgent care since many patients with respiratory symptoms may not need emergency care.

A commentary on this article was also published in NEJM Catalyst. Even for experienced clinicians, distinguishing between sore throats of viral and bacterial origin by observation alone is particularly challenging. Before most patients with a sore throat are prescribed antibiotics, the American Academy of Family Physicians recommends a positive diagnostic test for group A beta-hemolytic streptococci (GABHS). Empiric antibiotics, or antibiotics without a test, should be limited because they aren’t effective for viral infections and because unneeded antibiotics can cause side effects and antibiotic resistance.

In May and June 2021, we reported that RSV and seasonal influenza cases dropped during the COVID-19 pandemic.  Respiratory viruses other than COVID, like RSV and Influenza, were purported to increase again after measures like masking and social distancing were relaxed in the summer of 2021. EHR data for positive RSV and influenza tests show that the number of RSV cases has risen sharply since May 2021 while the number of influenza cases remains uncharacteristically low.

On June 29, 2021, we reported that 0.049% of patients fully vaccinated for COVID-19 developed a breakthrough COVID infection. This data included 8,662,367 fully vaccinated patients, of which 4,260 had a breakthrough COVID case. Patients were considered “fully vaccinated” 14 days after completing a manufacturer-recommend COVID-19 vaccination series (i.e., 14 days after the second dose of Pfizer-BioNTech, the second dose of Moderna, or the first dose of J&J/Janssen). Breakthrough cases were defined as those with a positive PCR-based SARS-CoV-2 test result and/or a COVID-19 diagnosis at least 14 days following the final dose in the series. The initial data included patients who were fully vaccinated on or before May 9, 2021.

Patients who are more engaged in their healthcare often have better outcomes. Because patient portal use is one marker of engagement, we wondered whether access to a patient portal correlated with hospital length of stay for certain conditions. To test this, we looked at two different types of admissions: admissions for new illness (COVID-19) and admissions for chronic illness (heart failure). Patients who were hospitalized for either COVID-19 or heart failure were more likely to have shorter hospital stays if they had an active patient portal account.

Starting at age 35, pregnancies are considered to be high risk due to advanced maternal age and can result in complications for both the patient and the baby. Adolescent patients also face risks in pregnancy. We reviewed 1.45 million live births for patients ages 13 to 45 between January 1, 2016, and June 1, 2021, and found that rates for some complications increase as patients get older while rates for other complications are higher for both younger and older patients.

In the early months of the pandemic, many hospitals stopped performing elective surgical procedures at the recommendation of the American College of Surgeons and the U.S. Surgeon General. We investigated whether common elective surgeries have returned to expected levels.

Polypharmacy, often defined as the use of five or more medications, is prevalent in adults ages 65 and older, with 40% taking 5-9 medications and 18% taking 10 or more. While drug-drug interactions and side effects are possible in all age groups, they are more prevalent in patients over 65, especially for certain medications. The American Geriatric Society publishes the Beers Criteria for Potentially Inappropriate Medication Use in Older Adults, which lists medications that should not be prescribed for patients 65 and older in most circumstances due to likely adverse events, like confusion.

Recent studies have suggested a possible association between the mRNA COVID-19 vaccination and myocarditis, an inflammation of the heart muscle. The CDC is actively reviewing rare reports of post-vaccination myocarditis, especially in adolescent males.

There has been an increase in telehealth visits across multiple specialties since the start of the pandemic. Prior to the pandemic, children needing evaluation for cognitive delays were seen in person. During the pandemic, many children needed to complete testing via telehealth, also known as teletesting. Although studies show telehealth is increasing as a method for providing cognitive therapies, psychologists were concerned that administering cognitive and academic via teletesting may not be valid since those tests were designed for in-person evaluations.

According to both researchers and the media, reports of gun violence rose significantly in 2020. We reviewed EHR data for patients who sought care for at least one new firearm incident. The data show a sharp increase in incidents starting in late spring 2020, with monthly incidents peaking in October 2020 at 73% higher than the monthly average in 2018 and 2019.

A previous EHRN study showed that immunizations for pediatric patients decreased by 42% in the spring of 2020. We completed a follow-up study of 6,525,735 pediatric patients to assess whether pandemic-era immunization rates for CDC-recommended immunizations have returned to historical rates. As shown in Figure 1, younger age groups have largely returned to predicted levels while older groups have remained below expected levels.

Definitions and guidance regarding the evaluation and care for patients with “Long COVID,” post-COVID conditions or PASC (post-acute sequalae of COVID-19) continues to evolve. We sought to describe health care utilization over time after an initial COVID-19 diagnosis. For the purpose of this analysis, follow-up after a health care claim with a confirmed or probable COVID-19 diagnosis was divided into three timeframes including a ≤30-day acute period and 2 subsequent post-acute periods of 31-90 days and 91-180 days.

In the U.S., children are at greater risk of environmental lead exposure if they live in housing built before 1978 or in households at or below the federal poverty level.

Early in the COVID-19 pandemic, stay-at-home measures, potential risk of COVID infection at a hospital or doctors’ offices, and concerns over hospital capacity led to sharp declines in health care utilization and spending, including drops in hospital admissions for both acute and elective procedures. There was also a drop in preventive service use. Spending decreased across all health services. While telemedicine use increased rapidly during the pandemic, it did not offset the decrease in in-person care.

More than 32 million Americans have type 2 diabetes, with an estimated 1.8 million new cases diagnosed each year. An elevated BMI is a known risk factor for the development of type 2 diabetes. We investigated whether a patient’s BMI was associated with greater diabetic control, as indicated by an A1C of less than 7% one year from initial diagnosis.  

In a previous EHRN study, we found mothers that tested positive for COVID-19 experienced greater rates of preterm birth and low birth weight than mothers that tested negative for COVID-19. Other early studies of COVID-19 vaccination in pregnancy point to the vaccine’s safety. With the increase in availability of the COVID-19 vaccine, we analyzed a large population of COVID-vaccinated mothers’ risk of preterm birth or low birth weight compared to babies born to unvaccinated mothers. Nearly all women who were vaccinated in their first trimester have not yet given birth; therefore, this study looked only at second and third trimester vaccination outcomes.

We examined 5,358,498 pediatric patient records to determine whether the patients gained more weight than expected during the COVID-19 pandemic. We found that prior to the pandemic, 23.9% of pediatric patients were above their expected weight, while during the pandemic period, 33.8% of pediatric patients were above their expected weight, a 41% increase from the pre-pandemic period.

To better understand the prevalence of long-haul symptoms after COVID-19 infection, we studied 693,375 patients diagnosed with COVID-19 who did not have prior indication of a long-haul symptom before their COVID positivity. We found that 9.4% sought treatment after their diagnosis for symptoms that might indicate long-haul COVID, as shown in Figure 1.