Identification of congenital CMV cases in administrative databases and implications for monitoring prevalence, healthcare utilization, and costs

Congenital cytomegalovirus diagnosis: healthcare claims data of linked pregnant people-infant pairs, United States, 2018-2023

OBJECTIVE

To describe maternal demographics and compare clinical characteristics of infants with congenital cytomegalovirus (cCMV) identified through diagnostic codes and laboratory data in the United States during 2018-2023.

METHODS

We used a CDC-licensed subset of HealthVerity data, which contained linked pregnant people-infant claims data from publicly and privately insured individuals during 2018-2023 (2023 Quarter 3 HealthVerity Maternal Outcomes Masterset data). We identified infants with cCMV using diagnostic codes or positive laboratory test results within 45 days of birth.

RESULTS

Among 744 (4.6 per 10,000 live births) infants with cCMV during 2018-2023, 599 (81%) were identified by a diagnostic code only. Among 732 linked pregnant people, 91 (12%) had a diagnosis of CMV infection during pregnancy, with a similar distribution by age group and insurance type, but a lower proportion were Black as compared to those without CMV infection during pregnancy (14% vs. 29%, respectively). Overall, 452 (61%) infants had ≥1 cCMV-related clinical sign at birth and 185 (25%) had valganciclovir prescriptions. Eighty-eight (68%) infants identified by a positive laboratory test only had no cCMV-related signs and none had valganciclovir prescriptions.

CONCLUSIONS

Using healthcare claims data, we found a minimal overlap of cCMV identified by diagnostic codes and laboratory test results. A minority of linked pregnant people with infants with cCMV had a CMV diagnosis during pregnancy. cCMV surveillance will help better understand the validity of ICD codes to identify infants with cCMV, describe the spectrum of disease, and monitor the use of antivirals.

Useful Clinical Criteria for Identifying Neonates with Congenital Cytomegalovirus Infection at Birth in the Context of an Expanded Targeted Screening Program

Cytomegalovirus (CMV) is the leading infectious cause of brain defects and neurological dysfunctions, including sensorineural hearing loss (SNHL). Targeted screening in neonates failing the hearing screen is currently recommended in Italy according to national guidelines. However, SNHL may not be present at birth; also, congenital CMV (cCMV) may manifest with subtle signs other than SNHL. Therefore, the inclusion of additional criteria for cCMV screening appears clinically valuable. Starting January 2021, we have implemented expanded targeted cCMV screening at our center, with testing in case of maternal CMV infection during pregnancy, inadequate antenatal care, maternal HIV infection or immunosuppression, birthweight and/or head circumference < 10th centile, failed hearing screen, and prematurity. During the first three years of use of this program (2021-2023), 940 (12.3%) of 7651 live-born infants were tested. The most common indication was birthweight < 10th centile (n = 633, 67.3%). Eleven neonates were diagnosed as congenitally infected, for a prevalence of 1.17% (95%CI 0.48-1.86) on tested neonates and of 0.14% (95%CI 0.06-0.23) on live-born infants. None of the cCMV-infected newborns had a failed hearing screen as a testing indication. Implementation of an expanded cCMV screening program appears feasible and of clinical value.

Autism Spectrum Disorder Diagnoses and Congenital Cytomegalovirus

OBJECTIVE

To examine the association between congenital cytomegalovirus (cCMV) and autism spectrum disorder (ASD) administrative diagnoses in US children.

METHODS

Cohort study using 2014 to 2020 Medicaid claims data. We used diagnosis codes to identify cCMV (exposure), ASD (outcome), and covariates among children enrolled from birth through ≥4 to <7 years. Covariates include central nervous system (CNS) anomaly or injury diagnosis codes, including brain anomaly, microcephaly within 45 days of birth, cerebral palsy, epilepsy, or chorioretinitis. We used Cox proportional hazards regression models to estimate hazard ratios and 95% confidence intervals, overall and stratified by sex, birth weight and gestational age outcome (low birth weight or preterm birth), and presence of CNS anomaly or injury.

RESULTS

Among 2 989 659 children, we identified 1044 (3.5 per 10 000) children with cCMV and 74 872 (25.0 per 1000) children with ASD. Of those with cCMV, 49% also had CNS anomaly or injury diagnosis codes. Children with cCMV were more likely to have ASD diagnoses (hazard ratio: 2.5; 95% confidence interval: 2.0-3.2, adjusting for birth year, sex, and region). This association differed by sex and absence of CNS anomaly or injury but not birth outcome.

CONCLUSIONS

Children with (versus without) cCMV diagnoses in Medicaid claims data, most of whom likely had symptomatic cCMV, were more likely to have ASD diagnoses. Future research investigating ASD risk among cohorts identified through universal cCMV screening may help elucidate these observed associations.

Estimates of congenital cytomegalovirus-attributable infant mortality in high-income countries: A review

As many as 5%-10% of infants with symptomatic congenital cytomegalovirus (cCMV) disease, or 0.4%-0.8% of all liveborn infants with cCMV infection, die in early infancy in high-income countries. However, estimates are uncertain due to several potential biases that can result from data limitations and study designs. First, infants with cCMV infections who die prior to diagnosis, which usually occurs at 1-4 weeks after birth, may be excluded from both the count of deaths and the denominator of cCMV births, resulting in left truncation and immortal time biases. These 'biases' are features of the data and do not reflect bias on the part of researchers, but understanding the potential existence of threats to validity can help with interpretation of findings. Left truncation of infant deaths occurring prior to diagnosis of cCMV can result in understatement of the burden of infant deaths due to cCMV. Conversely, overestimation of infant deaths associated with symptomatic cCMV may occur in clinical case series owing to greater representation of relatively severely affected infants owing to ascertainment and referral biases. In this review, we summarise the characteristics of 26 studies that reported estimates of cCMV-associated infant deaths, including potential biases or limitations to which those estimates may have been subject. We discuss study designs whose implementation might generate improved estimates of infant deaths attributable to cCMV. More complete estimates of the overall public health impact of cCMV could inform current and future screening, prevention, and vaccine research.

Burden of sequelae and healthcare resource utilization in the first year of life in infants born with congenital cytomegalovirus (cCMV) infection in Germany: A retrospective statutory health insurance claims database analysis

BACKGROUND

Congenital cytomegalovirus (cCMV) infection can have a broad range of manifestations. This study aimed to assess cCMV-associated sequelae and healthcare resource utilization (HCRU) in infants during the first year of life in Germany.

METHODS

A retrospective, controlled cohort study using German claims data from the Institute for Applied Health Research Berlin (InGef) database was conducted. cCMV-associated sequelae and HCRU during the first year of life were assessed by matching (1:60) infants with at least one inpatient/outpatient cCMV diagnosis (ICD-10-GM: P35.1) ≤90 days after birth (cCMV90 cohort) and infants with at least one inpatient cCMV diagnosis plus specific sequelae ≤21 days after birth (cCMV21-S) to infants without cCMV or CMV (ICD-10-GM: B25) diagnosis (control group), respectively. Outcomes were analyzed during the first 365 days of life.

RESULTS

Between 2014-2018, we identified 54 newborns for cCMV90 and 24 newborns for cCMV21-S cohort. Compared to the 3,240 and 1,440 controls, respectively, more cCMV90 infants (83.3% vs. 41.9%, p<0.01) presented with at least one sequela during the first year of life, including intrauterine growth retardation (42.6% vs. 5.3%, p<0.01), sensorineural hearing loss (SNHL) to deafness (38.9% vs. 2.2%, p<0.01), and motor development disorders (33.3% vs. 10.9%, p<0.01). Further, 13.0% of cCMV90 infants (vs. 2.3%, p<0.01) suffered from visual impairment. In cCMV21-S cohort, intrauterine growth retardation (79.2% vs. 6.0%, p<0.01), prematurity (54.2% vs. 7.3%, p<0.01), and motor development disorders (50.0% vs. 11.0%, p<0.01) were the most frequent sequelae. Infants in the cCMV90 and cCMV21-S cohort had, on average, 7.3 times and 9.5 times more hospitalizations and 2.0 times and 2.1 times more outpatient physician visits than their respective controls (p<0.01). Hospitalized infants with cCMV stayed, on average, significantly longer in hospital compared to their controls (cCMV90 cohort: 30.3 days vs. 9.0 days, p<0.01; cCMV21-S cohort: 46.5 days vs. 9.3 days, p<0.01).

CONCLUSIONS

cCMV-infection shows a considerable disease and healthcare burden during the first year of life. More than 80% of the identified newborns with cCMV suffered from at least one associated sequela during the first year of life, including long-term sequelae such as SNHL (40%) and visual impairment (13%). Additional steps for prevention of cCMV infection and associated sequelae as well as a comprehensive monitoring of disease burden are needed.

A systematic literature review of the economic and healthcare resource burden of cytomegalovirus

OBJECTIVE

Cytomegalovirus (CMV) can infect individuals at any age, including infants, who may contract it from infected mothers (congenital CMV [cCMV]). Whereas CMV infection is typically asymptomatic or causes mild illness in healthy individuals, infection can result in severe outcomes in immunocompromised individuals and in infants with cCMV. This systematic review aims to characterize the economic impact of CMV and cCMV infections.

METHODS

Medline, Embase, and LILACS databases were searched for publications reporting the economic impact of cCMV and CMV infections across all age groups. Manuscripts published between 2010 and 2020 from Australia, Latin America, Canada, Europe, Israel, Japan, the United States, and global (international, worldwide) studies were included; congress materials were excluded. Outcomes of interest included cCMV- and CMV-attributable direct costs/charges, resource utilization, and indirect/societal costs.

RESULTS

Of 751 records identified, 518 were excluded based on duplication, population, outcome, study design, or country. Overall, 55 articles were eligible for full-text review; 25 were further excluded due to population, outcome, study design, or congress abstract. Two publications were additionally identified, resulting in economic impact data compiled from 32 publications. Of these, 24 publications reported cost studies of cCMV or CMV, including evaluation of direct costs/charges, healthcare resource utilization, and indirect/societal costs, and 7 publications reported economic evaluations of interventions. The populations, methods and outcomes used across these studies varied widely.

CONCLUSIONS

CMV and cCMV infections impose a considerable economic impact on different countries, populations, and outcomes. There are substantial evidence gaps where further research is warranted.

The Psychosocial Impact of Congenital Cytomegalovirus on Caregivers and Families: Lived Experiences and Review of the Literature

Caring for a child with congenital cytomegalovirus (cCMV) can be costly for families, not only in terms of out-of-pocket expenses, but also in terms of caregiver time, relationships, career trajectories, and mental health. These additional burdens are sometimes referred to as "spillover effects". As parents of children with cCMV, we, the authors of this article, discuss the impact that cCMV has had on our families. While multiple studies have reported on the epidemiology, prevention, screening, diagnosis, and management of cCMV, there has been minimal research regarding the possible impact on the family unit. In this narrative review, we discuss the various areas of the lives of families and caregivers that may be impacted by raising a child with cCMV. Whether children are minimally or severely affected by the sequelae of cCMV, they and their families merit the progression of awareness of the virus and governmental policies to help end cCMV. As the existing cCMV-specific literature is limited, we correlate studies of other childhood disabilities and find the mutuality experienced by families affected by cCMV.

Cytomegalovirus seronegativity rate in pregnant women and primary cytomegalovirus infection during pregnancy in rural Germany

BACKGROUND

Congenital cytomegalovirus (CMV) infection is the most common congenital infection worldwide and one of the leading causes of congenital hearing loss in newborns. The aim of this study was to determine the seroprevalence rate for cytomegalovirus in pregnant women and the rate of CMV serological testing utilised during pregnancy in a rural region in Germany.

METHODS

Retrospective data on the prevalence of CMV IgG and IgM antibodies were obtained from 3,800 women, identified in the study group of 19,511 pregnant women from outpatient settings whose samples were collected between 1 and 2014 and 30 April 2018. In addition, the serological CMV status in regards to various billing methods was further analyzed.

RESULTS

Serological CMV tests were performed in 3,800 (19.5%) out of 19,511 pregnant women. 2,081 (54.8%) of these women were CMV seronegative. Among those, seroconversion rate of 0.37-1.42% was identified. A proportion of 2,710 (14.7%) of all 18,460 women with statutory health insurance made use of the CMV testing as an individual health service.

CONCLUSIONS

The low uptake of CMV serological testing in the study population covered indicates low risk awareness among pregnant women and their healthcare professionals. Presented seronegativity rates and routine seroconversion rate, demonstrate importance to improve intervention strategy to prevent feto-maternal CMV transmission.

Healthcare costs of congenital cytomegalovirus (cCMV) disease in infants during the first two years of life: a retrospective German claims database analysis

BACKGROUND

Congenital cytomegalovirus (cCMV) infection can cause severe neurological damage, growth retardation, hearing loss, and microcephaly in infants. We aimed at assessing healthcare costs of infants with recorded cCMV diagnosis in an administrative claims database in the first 2 years of life.

METHODS

We conducted a retrospective, controlled cohort study using German claims data from the Institute for Applied Health Research Berlin (InGef) database. Incremental healthcare costs during the first and second year of life were assessed by matching (1:60) infants with cCMV diagnoses ≤ 90 days after birth (cCMV₉₀ cohort) to infants without cCMV diagnosis ("representative" controls) and infants with cCMV diagnoses ≤ 21 days after birth plus specific symptoms (cCMV_21-S) to infants without cCMV and any ICD-10-GM records (besides Z00-Z99) until 4^th preventive health check-up ("healthy" controls). Due to missing data, mean imputation was applied for aids and remedies costs.

RESULTS

We identified 54 and 24 infants born 2014-2018 for the cCMV₉₀ and cCMV_21-S cohorts, respectively. During the first year, mean (median) healthcare costs were significantly higher in cCMV₉₀ cases vs. "representative" controls (€22,737 (€9759) vs. €3091 (€863), p < 0.001), with 87.2% inpatient costs. Healthcare costs for cCMV_21-S cases compared to "healthy" controls were €34,498 (€20,924) vs. €680 (€569), p < 0.001. Differences decreased for both comparisons in the second year but remained statistically significant.

CONCLUSIONS

cCMV comprises a considerable economic burden for the German healthcare system (€19,646 to €33,818 higher mean costs for infants with recorded cCMV diagnosis in the first year of life). Attempts should be made to reduce this burden.

Modeling of vertical transmission and pathogenesis of cytomegalovirus in pregnancy: Opportunities and challenges

In addition to facilitating nutrient, oxygen, and waste transfer between developing fetus and mother, the placenta provides important immune barrier function against infection. Elucidation of the complexity of placental barrier function at the maternal-fetal interface has been greatly aided through experimental model organism systems. In this review, we focus on models of vertical transmission of cytomegalovirus (CMV), a ubiquitous double-stranded DNA viruses whose vertical transmission during pregnancy can lead to devastating neurological and obstetric sequelae. We review the current evidence related to guinea pig and murine models of congenital CMV infection, discuss the possible translatability of a non-human primate model, and conclude with recently developed technology using human placental organoids.

Congenital cytomegalovirus surveillance in the United States

BACKGROUND

Congenital cytomegalovirus (cCMV) is not a nationally notifiable condition, and little is known about how U.S. health departments (HDs) currently conduct cCMV surveillance.

METHODS

We surveyed U.S. HDs that conduct cCMV surveillance or screening activities identified through a web-based assessment. Meetings were held with each HD to enhance our understanding of survey responses.

RESULTS

Ten states are systematically collecting cCMV case data to track cCMV cases during early infancy and to provide resources and services to families. Cases are ascertained using cCMV diagnostic codes, reported diagnosis, or laboratory results. Data elements collected for each case include demographics (all 10 states), clinical signs (8 states), laboratory data (4 states), treatment (4 states), and long-term outcomes (1 state). Annual number of cases reported by HDs ranged from 3 to 47 cases/year in seven states, which was much lower than the expected number of cCMV cases. All 10 HDs have the ability to analyze data collected and four disseminate findings. Major challenges of surveillance reported by HDs were lack of standardized case definitions, personnel constraints, and limited funding.

CONCLUSIONS

A comprehensive account of cCMV disease burden is severely limited by low case ascertainment and paucity of data on long-term outcomes. A standardized public health case definition for cCMV would improve consistency in measuring disease prevalence across jurisdictions and over time. Surveillance for cCMV has the potential to increase disease awareness and inform strategies to prevent cCMV-associated disabilities.

Inconsistent Provider Testing Practices for Congenital Cytomegalovirus: Missed Diagnoses and Missed Opportunities

Newborn congenital cytomegalovirus (cCMV) screening programs have been found to increase the rates of early diagnosis and treatment. In North America, newborn cCMV screening programs have not been widely implemented, leaving healthcare providers to rely on clinical suspicion alone to prompt testing. This study sought to examine healthcare providers' cCMV testing practices at a quaternary children's hospital. A retrospective review of the electronic health record was completed for eligible infants over a six-year period. Bivariate calculations and analyses were performed. Between 2014 and 2019, a total of 40,091 infants were cared for at the study institution, of which 178 were tested for cCMV and 10 infants were diagnosed with cCMV. Isolated small-for-gestational age was the most common indication (53/178) to prompt testing. Overall, the cCMV testing rate was 4.5 tests per 1000 infants, with a resulting diagnostic prevalence of 0.2 cases per 1000 infants, which is 15-fold lower than the expected prevalence. Providers relying on clinical suspicion alone are infrequently testing infants for cCMV, resulting in missed diagnoses and missed opportunities for treatment. Systematic cCMV screening practices may improve diagnosis, treatment, and childhood outcomes.

Changes in Valganciclovir Use Among Infants with Congenital Cytomegalovirus Diagnosis in the United States, 2009-2015 and 2016-2019

From 2009-2015 to 2016-2019, the proportion of infants in the US with congenital cytomegalovirus treated with valganciclovir roughly doubled for infants enrolled with employer-sponsored insurance (from 16% to 29%) and Medicaid (from 16% to 36%). The proportion treated with valganciclovir increased for all congenital cytomegalovirus disease severity groups.

Missing diagnoses of congenital cytomegalovirus infection in electronic health records for infants with laboratory-confirmed infection

Congenital cytomegalovirus (CMV) is a leading cause of non-genetic sensorineural hearing loss and neurodevelopmental disabilities among US children. Studies using administrative healthcare databases have identified infants with congenital CMV using diagnostic codes from the International Classification of Diseases, Ninth and Tenth Revision, Clinical Modification. Using Cerner Health Facts deidentified electronic health records, we assessed the sensitivity of CMV diagnostic codes among infants with laboratory confirmed congenital CMV infection (i.e. a positive CMV laboratory test - polymerase chain reaction, direct fluorescent antibody, or culture from urine, saliva, respiratory secretion or blood samples, or IgM serology - within 21 days of life). During 2010-2017, 668 congenital CMV cases were identified among 7,517,207 infants with encounters within 21 days of life, or 0.89 cases per 10,000 infants. The sensitivity of CMV diagnostic codes assigned within 21 and 90 days of life was 10.3% (95% CI: 8.2-12.9) and 11.1% (95% CI: 8.9-13.7), respectively.

Health Care Resource Utilization and Economic Burden Associated With Congenital Cytomegalovirus Infection: A Longitudinal Analysis of Data From Clinical Practice at a Large Health Care Provider in Israel

PURPOSE

Congenital cytomegalovirus infection (cCMVi) is the leading cause of nonhereditary sensorineural hearing loss and can cause other long-term neurodevelopmental disabilities; however, data on the economic burden of cCMVi during early childhood are scarce. The primary objective of the study was to describe longitudinal patterns of health care resource utilization (HCRU) and direct medical costs among infants with cCMVi compared to infants unexposed to cCMVi.

METHODS

A retrospective cohort study was performed using data on infants born between 2013 and 2017, as captured in the database of Maccabi Healthcare Services, a 2.5 million-member health care organization in Israel. cCMVi cases were identified by physician diagnosis and/or dispensed valganciclovir within 90 days after birth. Infants born to mothers CMV-seronegative throughout pregnancy were selected for comparison (unexposed controls). Infants were retrospectively followed up through December 31, 2018, or 4 years of age (Y4). HCRU included physician visits, hospital admissions, audiology tests/procedures, imaging, and valganciclovir treatment. Direct medical costs, in US dollars per person per year (USD PPPY) were calculated from the health-system perspective. To compare costs of cCMVi cases and controls, direct medical costs were estimated using a generalized linear model with a log link function and γ distribution after adjustment for patient characteristics.

FINDINGS

A total of 351 cCMVi cases and 11,733 control infants with continuous follow-up during their first year of life (Y1) were included in the study. In Y1, cases were more likely to have a hospital admission (8.5% cases vs 4.5% control; P < 0.001) and higher numbers of pediatrician visits (median, 18 vs 15), audiology visits and tests, and cranial ultrasounds (all, P < 0.05). Longitudinally, incremental costs associated with cases were highest in Y1 (1686.7 USD PPPY; cost ratio = 2.6; P < 0.001) and remained elevated through Y4.

IMPLICATIONS

cCMVi was associated with substantial increases in HCRU and economic burden during early childhood, and particularly during the first year of life.