Secular trends in diagnostic code density in electronic healthcare data from health care systems in the Vaccine Safety Datalink Project

Disparities in Outpatient and Telehealth Visits During the COVID-19 Pandemic in a Large Integrated Health Care Organization: Retrospective Cohort Study

Background

Dramatic decreases in outpatient visits and sudden increases in telehealth visits were observed during the COVID-19 pandemic, but it was unclear whether these changes differed by patient demographics and socioeconomic status.

Objective

This study aimed to assess the impact of the pandemic on in-person outpatient and telehealth visits (telephone and video) by demographic characteristics and household income in a diverse population.

Methods

We calculated weekly rates of outpatient and telehealth visits by age, sex, race/ethnicity, and neighborhood-level median household income among members of Kaiser Permanente Southern California (KPSC) from January 5, 2020, to October 31, 2020, and the corresponding period in 2019. We estimated the percentage change in visit rates during the early pandemic period (March 22 to April 25, 2020) and the late pandemic period (October 4 to October 31, 2020) from the prepandemic period (January 5 to March 7, 2020) in Poisson regression models for each subgroup while adjusting for seasonality using 2019 data. We examined if the changes in visit rates differed by subgroups statistically by comparing their 95% CIs.

Results

Among 4.56 million KPSC members enrolled in January 2020, 15.0% (n=682,947) were ≥65 years old, 51.5% (n=2,345,020) were female, 39.4% (n=1,795,994) were Hispanic, and 7.7% (n=350,721) lived in an area of median household income <US $40,000. Increases in telehealth visits during the pandemic varied across subgroups, while decreases in outpatient visits were similar, except by age. Among age groups, the ≥65 years population had the least increase in telehealth visits (236.6%, 95% CI 228.8%-244.5%), with 4.9 per one person-year during the early pandemic period versus 1.5 per one person-year during the prepandemic period. During the same periods, across racial/ethnic groups, Hispanic individuals had the largest increase in telehealth visits (295.5%, 95% CI 275.5%-316.5%). Across income levels, telehealth visits in the low-income group increased the most (313.5%, 95% CI 294.8%-333.1%). The rate of combined outpatient and telehealth visits in the Hispanic, non-Hispanic Black, and low-income groups returned to prepandemic levels by October 2020.

Conclusions

The Hispanic group and low-income group had the largest percentage increase in telehealth utilization in response to the COVID-19 pandemic. The use of virtual care potentially mitigated the impact of the pandemic on health care utilization in these vulnerable populations.

Developing algorithms for identifying major structural birth defects using automated electronic health data

PURPOSE

Given the 2015 transition to International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) diagnostic coding, updates to our previously published algorithms for major structural birth defects (BDs) were necessary. Aims of this study were to update, validate, and refine algorithms for identifying selected BDs, and then to use these algorithms to describe BD prevalence in the vaccine safety datalink (VSD) population.

METHODS

We converted our ICD-9-CM list of selected BDs to ICD-10-CM using available crosswalks with manual review of codes. We identified, chart reviewed, and adjudicated a sample of infants in the VSD with ≥2 ICD-10-CM diagnoses for one of seven common BDs. Positive predictive values (PPVs) were calculated; for BDs with suboptimal PPV, algorithms were refined. Final automated algorithms were applied to a cohort of live births delivered 10/1/2015-9/30/2017 at eight VSD sites to estimate BD prevalence. This research was approved by the HealthPartners Institutional Review Board, by all participating VSD sites, and by the CDC, with a waiver of informed consent.

RESULTS

Of 573 infants with ≥2 diagnoses for a targeted BD, on adjudication, we classified 399 (69.6%) as probable cases, 31 (5.4%) as possible cases and 143 (25.0%) as not having the targeted BD. PPVs for the final BD algorithms ranged from 0.76 (hypospadias) to 1.0 (gastroschisis). Among 212 857 births over 2 years following transition to ICD-10-CM coding, prevalence for the full list of selected defects in the VSD was 1.8%.

CONCLUSIONS

Algorithms can identify infants with selected BDs using automated healthcare data with reasonable accuracy. Our updated algorithms can be used in observational studies of maternal vaccine safety and may be adapted for use in other surveillance systems.

Challenges and Opportunities for Using Big Health Care Data to Advance Medical Science and Public Health

Methodological advancements in epidemiology, biostatistics, and data science have strengthened the research world's ability to use data captured from electronic health records (EHRs) to address pressing medical questions, but gaps remain. We describe methods investments that are needed to curate EHR data toward research quality and to integrate complementary data sources when EHR data alone are insufficient for research goals. We highlight new methods and directions for improving the integrity of medical evidence generated from pragmatic trials, observational studies, and predictive modeling. We also discuss needed methods contributions to further ease data sharing across multisite EHR data networks. Throughout, we identify opportunities for training and for bolstering collaboration among subject matter experts, methodologists, practicing clinicians, and health system leaders to help ensure that methods problems are identified and resulting advances are translated into mainstream research practice more quickly.

CURB-65 Performance Among Admitted and Discharged Emergency Department Patients With Community-acquired Pneumonia

OBJECTIVES

Pneumonia severity tools were primarily developed in cohorts of hospitalized patients, limiting their applicability to the emergency department (ED). We describe current community ED admission practices and examine the accuracy of the CURB-65 to predict 30-day mortality for patients, either discharged or admitted with community-acquired pneumonia (CAP).

METHODS

A retrospective, observational study of adult CAP encounters in 14 community EDs within an integrated healthcare system. We calculated CURB-65 scores for all encounters and described the use of hospitalization, stratified by each score (0-5). We then used each score as a cutoff to calculate sensitivity, specificity, positive predictive value, negative predictive value (NPV), positive likelihood ratios, and negative likelihood ratios for predicting 30-day mortality.

RESULTS

The sample included 21,183 ED encounters for CAP (7,952 discharged and 13,231 admitted). The C-statistic describing the accuracy of CURB-65 for predicting 30-day mortality in the full sample was 0.761 (95% confidence interval [CI], 0.747-0.774). The C-statistic was 0.864 (95% CI, 0.821-0.906) among patients discharged from the ED compared with 0.689 (95% CI, 0.672-0.705) among patients who were admitted. Among all ED encounters a CURB-65 threshold of ≥1 was 92.8% sensitive and 38.0% specific for predicting mortality, with a 99.9% NPV. Among all encounters, 62.5% were admitted, including 36.2% of those at lowest risk (CURB-65 = 0).

CONCLUSIONS

CURB-65 had very good accuracy for predicting 30-day mortality among patients discharged from the ED. This severity tool may help ED providers risk stratify patients to assist with disposition decisions and identify unwarranted variation in patient care.

Maternal influenza vaccine and risks for preterm or small for gestational age birth

OBJECTIVE

To study the impact of influenza vaccine administered to pregnant women during all trimesters on the rates of preterm and small for gestational age (SGA) births, evaluating both increased and decreased risk.

STUDY DESIGN

This retrospective observational matched cohort study involved 7 Vaccine Safety Datalink sites across the US for the 2004-05 through 2008-09 influenza seasons. Cohort eligibility and outcomes were determined from administrative, claims, medical records, and birth data. In propensity score- and vaccine exposure time-matched analyses, ORs for preterm and SGA births were calculated.

RESULTS

Among 57 554 matched vaccinated and unvaccinated pregnant women, including 16 240 women in the first trimester, maternal vaccination was not associated with increased or decreased risk for preterm birth (OR for delivery at <37 weeks gestation, 0.97 [95% CI, 0.93-1.02]; for delivery at ≤32 weeks gestation, 0.98 [95% CI, 0.86-1.12]; and for delivery at ≤34 weeks gestation, 0.96 [95% CI, 0.88-1.04]) or SGA birth (OR for <5th percentile weight for gestational age, 1.02 [95% CI, 0.96-1.09], and for <10th percentile weight for gestational age, 1.00 [95% CI, 0.96-1.04]). Similarly, first trimester vaccination was not associated with increased or decreased risk for preterm or SGA birth.

CONCLUSION

Receipt of trivalent inactivated influenza vaccine during pregnancy was not associated with increased or decreased risk of preterm or SGA birth. These findings support the safety of vaccinating pregnant women against influenza during the first, second, and third trimesters, and suggest that a nonspecific protective effect of the influenza vaccine for these outcomes does not exist.