Highly variable population-based prevalence rates of unilateral hearing loss after the application of common case definitions.

OBJECTIVES: This study shows how population-based estimates of the prevalence of unilateral hearing loss (UHL) in children aged 6 to 19 yrs can differ considerably with various applications of commonly accepted case definitions. It also examines demographic variables and risk factors related to UHL. DESIGN: The Third National Health and Nutrition Examination Survey, conducted from 1988 to 1994, is a national population-based, cross-sectional survey. This study examined results of audiometric testing at 0.5 to 8 kHz and demographic data from in-person examination interviews. Three definitions of UHL were used: (1) 0.5, 1, and 2 kHz > or = 15 dB pure-tone average (PTA); (2) 0.5, 1, 2, and 4 kHz > or = 15 dB PTA; and (3) 0.5, 1, and 2 kHz > or = 20 dB or PTA >25 dB at two or more frequencies above 2 kHz (3, 4, 6, and 8 kHz). Case definitions 2 and 3 are not merely subsets of case definition 1. Some overlap exists between the groups, but each case definition classifies a proportion of children who fall uniquely under that case definition. Inclusion of participants based on tympanometry results (test of middle ear function) was also examined as were demographic characteristics and risk factors associated with UHL. RESULTS: Overall, the weighted proportion of children with UHL using case definition 1 was 6.3% (approximately 3,213,000 children nationally); using case definition 2, it was 5.8% (approximately 2,958,000 nationally); using case definition 3, it was 3.0% (approximately 1,530,000 nationally). For all three case definitions, children who failed tympanometry were at higher risk for UHL than children who passed. For case definition 2, children from rural areas were at higher risk for UHL than were children from urban areas. CONCLUSIONS: This study demonstrates that different applications of well-accepted case definitions of UHL can influence population-based prevalence estimates, in this study by as much as a factor of 2. These findings highlight the importance of controlling for tympanometry status as a risk factor in such estimates. Which demographic characteristics and risk factors are significantly associated with hearing loss seem to vary depending on the case definition. These findings have implications for the interpretation of prevalence rates and risk factors in the literature on hearing loss in general. Prevalence rate estimates require careful consideration of the case definition of hearing loss, tympanometry status, and demographic characteristics.

Teratology: from science to birth defects prevention.

One of the goals of birth defects research is to better understand risk or preventive factors for birth defects so that strategies for prevention can be developed. In this article, we have selected four areas of birth defects research that have led to the development of prevention strategies. These areas include rubella virus as a cause of congenital rubella syndrome, folic acid as a preventive factor for neural tube defects, cytomegalovirus infection as a cause of birth defects and developmental disabilities, and alcohol as a cause of fetal alcohol spectrum disorders. For each of these areas, we review key clinical and research findings that led to the identification of the risk or preventive factor, milestones in the development of prevention strategies, and the progress made thus far toward prevention.

Congenital cytomegalovirus (CMV) infection as a cause of permanent bilateral hearing loss: a quantitative assessment.

BACKGROUND: Congenital cytomegalovirus (CMV) infection is a cause of sensorineural hearing loss (SNHL) in children, but the magnitude of its contribution is uncertain. Quantifying the impact of congenital CMV infection requires an evidence-based assessment using a standard case definition of hearing loss. OBJECTIVES: To determine the frequency of bilateral moderate to profound SNHL in children with congenital CMV infection and to estimate the CMV-attributable fraction of bilateral moderate to profound SNHL. STUDY DESIGN: A systematic review of studies of children with congenital CMV infection ascertained in an unbiased manner through universal newborn screening for CMV using viral culture in urine or saliva specimens in combination with a review of the literature on congenital CMV infection and hearing loss, including articles of all types. RESULTS: Approximately, 14% of children with congenital CMV infection develop SNHL of some type, and 3-5% develop bilateral moderate to profound SNHL. Among all children with bilateral moderate to profound SNHL, we estimate that 15-20% of cases are attributable to congenital CMV infection. CONCLUSIONS: Congenital CMV infection is one of the most important causes of hearing loss in young children, second only to genetic mutations, and is potentially preventable.

Early intervention for children with unilateral and mild bilateral degrees of hearing loss.

Some children with unilateral hearing loss or mild bilateral hearing loss are at risk for developmental delays, educational difficulties, and other adverse effects. However, these children face several challenges in receiving services that can prevent such problems. Many do not meet existing eligibility requirements for early intervention services in their state. Information disseminated to professionals and parents often does not convey the significance of unilateral and mild bilateral hearing loss. Some professionals indicate that there are insufficient guidelines defining appropriate intervention services for these children. Factors that influence developmental outcomes in this population are not well understood, making it difficult to determine which children can benefit from intervention services. Additional data are needed about how to minimize or prevent adverse outcomes in these children. This article presents suggestions for intervention and future research that were developed by participants of the 2005 National Workshop on Mild and Unilateral Hearing Loss.

Hearing screening and diagnostic evaluation of children with unilateral and mild bilateral hearing loss.

More than 90% of newborns in the United States are now being screened for hearing loss. A large fraction of cases of unilateral hearing loss and mild bilateral hearing loss are not currently identified through newborn hearing screening. This is of concern because a preponderance of research has demonstrated that unilateral hearing loss and mild bilateral hearing loss can lead to developmental delays and educational problems for some children. To help address this probable underidentification of unilateral hearing loss and mild bilateral hearing loss among infants and children, the Centers for Disease Control and Prevention Early Hearing Detection and Intervention program and the Marion Downs Hearing Center convened a workshop in Breckenridge, Colorado, in July 2005. During this workshop, several issues related to screening and diagnosing unilateral hearing loss and mild bilateral hearing loss were identified, as well as recommendations for future research in this area. Issues identified included the lack of standardized definitions for permanent unilateral hearing loss and mild bilateral hearing loss; the use of screening protocols that are primarily designed to identify bilateral and unilateral hearing losses of a moderate degree or greater (eg, above 40 dB); calibration of screening equipment; availability of facilities that can provide the full range of audiologic, diagnostic, and management services to this pediatric population; and an overall lack of awareness by many professionals and families about the potential effect of unilateral hearing loss and mild bilateral hearing loss. Suggestions for future research, such as identifying ways to improve the identification of cases of unilateral hearing loss and mild bilateral hearing loss, were also discussed.

Women's knowledge of congenital cytomegalovirus: results from the 2005 HealthStyles survey.

BACKGROUND: Congenital cytomegalovirus (CMV) is as common a cause of serious disability as Down syndrome and neural tube defects. When acquired prior to or during pregnancy, CMV can be transmitted transplacentally to the fetus, sometimes causing serious temporary symptoms, permanent disabilities, or both to the child. One way to prevent infection before and during pregnancy is through simple hygienic practices, such as handwashing. METHODS: This study used the 2005 annual HealthStyles survey, a mail survey of the U.S. population aged <18 years, to assess knowledge of congenital CMV. Self-reports by female respondents measured willingness to adopt particular hygienic behaviors to prevent CMV transmission. RESULTS: Only 14% of female respondents had heard of CMV. Among women who reported they had heard of CMV, the largest proportion said they had heard about it from a doctor, hospital, clinic, or other health professional (29%). The accuracy of women's knowledge of what conditions congenital CMV can cause in the fetus was limited. The prevention behaviors surveyed in the present study (i.e., handwashing, not sharing drinking glasses or eating utensils with young children, and not kissing young children on the mouth) appeared to be generally acceptable. CONCLUSIONS: There are prevention behaviors that have the potential of substantially reducing the occurrence of CMV-related permanent disability in children. However, our results suggest that few women are aware of CMV or these prevention behaviors.

The epidemiology and prevention of congenital cytomegalovirus infection and disease: activities of the Centers for Disease Control and Prevention Workgroup.

Perhaps no single cause of birth defects and developmental disabilities in the United States currently provides greater opportunity for improved outcomes in more children than congenital cytomegalovirus (CMV). --Cannon and Davis. BMC Public Health 2005;5:70 Each year in the United States, thousands of children and their families are affected by congenital cytomegalovirus (CMV) infection. More children may be affected by congenital CMV than by other, better known childhood conditions, such as Down syndrome, fetal alcohol syndrome, and spina bifida. The Centers for Disease Control and Prevention (CDC) has formed a Workgroup on Congenital CMV, led by the National Center on Birth Defects and Developmental Disabilities and the National Center on Infectious Diseases. This report provides background on congenital CMV infection and describes the goals and activities of the workgroup for reducing the burden of sequelae of congenital CMV infection.

The time course for language acquisition in biologically distinct populations: evidence from deaf individuals.

The present study provides evidence that individuals who have different patterns of cerebral lateralization and who develop along different maturational time courses can attain comparable levels of language proficiency. Right-handed individuals with left-handed family members (left-handed familials, LHFs) showed a shorter sensitive period for language acquisition than did right-handed individuals with only right-handed family members (right-handed familials, RHFs). The shorter sensitive period for LHFs may be due to a focus on non-linguistic, word-based conceptual information during language acquisition. RHFs may focus on grammatical relations during language acquisition, which matures later than lexical knowledge. This suggests that there may be different patterns of cerebral lateralization for language in all normal populations as a function of familial handedness.

Pediatric primary care physicians' practices regarding newborn hearing screening.

OBJECTIVE: Approximately 2 to 3 out of 1000 infants are born with hearing loss in the United States each year. Pediatric primary care physicians (PCPs) can play an important role in ensuring that infants with hearing loss are identified early and provided appropriate services. In this study, pediatric PCPs were surveyed about their practices regarding early hearing detection and intervention. METHODS: Responses from the 2008 DocStyles survey were used to examine patient, physician, and practice variables associated with actions consistent with the 2007 Joint Committee on Infant Hearing position statement, which includes follow-up protocols for medical home providers. RESULTS: Pediatricians working in a group setting were more likely to receive hearing screening results than were those in individual practices or hospitals and clinics. Family/general physicians with heavier caseloads were more likely to receive hearing screening results for their pediatric patients than were those with lighter caseloads. Few pediatric PCPs reported contacting their state's early hearing detection and intervention program if they knew that an infant failed the newborn hearing screening. Although high proportions of pediatric PCPs reported referring an infant with hearing loss to an otolaryngologist, only about half reported referring a child with risk factors for hearing loss for audiological and speech-language assessment, even if the parents expressed concern or if the results of a developmental screening indicated a possible delay. Few respondents reported referring an infant with hearing loss under their care to an ophthalmologist. CONCLUSIONS: This study highlights the need to improve infrastructure for pediatric PCPs to receive and request infant hearing screening results to facilitate reporting and coordinate follow-up services for infants identified with hearing loss.

Attitudes toward newborn screening for cytomegalovirus infection.

OBJECTIVE: Newborns are not routinely screened for cytomegalovirus (CMV), the leading infectious cause of developmental disability. Congenital CMV satisfies a number of criteria for inclusion in newborn screening, and screening potentially offers benefits. Screening could also introduce harms such as anxiety and unnecessary costs for the families of the substantial proportion of CMV-infected children who never develop CMV-related disabilities. Our objective was to assess attitudes toward newborn screening for CMV. METHODS: We analyzed responses to 5 statements about CMV and newborn screening from 3922 participants in the 2009 HealthStyles survey, a national mail survey designed to include a group similar to the US population with respect to gender, age, race/ethnicity, income, and household size. Two-step cluster analysis was performed to identify clusters of parental attitudes. RESULTS: The majority of respondents strongly or somewhat agreed that they would want to have their newborn tested for CMV even if it was not performed routinely (84%), they had to pay $20 (87%), or CMV-related problems never developed (84%). Nearly half (47%) of them "would worry that the CMV test would lead to unneeded doctor visits and expenses," and 32% "think CMV problems are too rare to worry about." Three clusters of parent respondents were identified on the basis of their attitudes toward CMV screening: "strongly in favor" (31%), "moderately in favor" (49%), and "weakly opposed" (20%). CONCLUSIONS: Among most parents, costs, worry, and anxiety associated with newborn screening for CMV would be acceptable. Although attitudes were generally favorable, a minority of the parents were weakly opposed to newborn screening for CMV.

Newborn screening for congenital cytomegalovirus: Options for hospital-based and public health programs.

BACKGROUND: Congenital cytomegalovirus (CMV) infection is a leading cause of sensorineural hearing loss (SNHL) and developmental disability in children. Early identification of infected children through screening could allow for early intervention and improvement in functional outcomes among the subset who develop sequelae. OBJECTIVES: To outline potential options and strategies for screening newborns for congenital CMV infection and to discuss barriers to screening and data needs to inform future policy decisions. STUDY DESIGN: Commentary based on the literature and expert opinion on newborn dried blood spot screening, newborn hearing screening/Early Hearing Detection and Intervention (EHDI) programs, and congenital CMV. RESULTS: Although no population-based screening for congenital CMV is underway, pilot newborn screening studies using a variety of assays with urine or dried blood spot specimens are underway. Challenges to screening are both practical-uncertain sensitivity of blood spot assays suitable for large-scale screening and lack of infrastructure for collection of urine specimens; and evidentiary-the need to demonstrate improved outcomes and value of screening to offset the expense and potential adverse psychosocial consequences for children and families whose children require periodic monitoring but never develop sequelae. CONCLUSIONS: Screening for congenital CMV infection is a potentially important intervention that merits additional research, including the logistical feasibility of different screening options and psychosocial consequences for families.

Unmet health care needs among CSHCN with neurologic conditions.

OBJECTIVE: Children with neurologic conditions require a variety of services. With this study we examined health care needs and unmet needs among children with neurologic conditions. METHODS: Cross-sectional data reported by parents of 3- to 17-year-olds in the 2005-2006 National Survey of Children With Special Health Care Needs were analyzed. Demographic characteristics, health care needs, and unmet needs of children with special health care needs (CSHCN) and neurologic conditions were descriptively compared with an independent referent group of children without special health care needs; statistical contrasts were performed as a function of the type (conditions included in the Diagnostic and Statistical Manual of Mental Disorders [DSM] or not) and number of reported neurologic conditions. RESULTS: Compared with the parents of children without special health care needs, parents of CSHCN with neurologic conditions were more likely to report unmet health care needs for their child. After adjustment for demographic factors and severity of functional limitation, CSHCN with at least 2 conditions had more visits to a health care provider, needed more services, and reported more unmet needs than CSHCN with a single DSM condition. The magnitude of need among CSHCN was greatest among those with at least 1 of each type of neurologic condition. CONCLUSIONS: Unmet health care needs exist among CSHCN with neurologic conditions and are particularly pronounced among children with a combination of both DSM and non-DSM disorders. The health care needs among CSHCN with multiple neurologic conditions may be better served by targeted efforts to improve care coordination.

Obstetrician/gynecologists' knowledge, attitudes, and practices regarding prevention of infections in pregnancy.

BACKGROUND: Maternal infection during pregnancy is a well-recognized cause of birth defects and developmental disabilities, as well as an important contributor to other adverse pregnancy outcomes. The objective of the present survey was to gain information about the knowledge, attitudes, and practices of obstetrician/gynecologists regarding prevention of infections during pregnancy. METHODS: A survey was mailed to 606 Collaborative Ambulatory Research Network (CARN) members of the American College of Obstetricians and Gynecologists (ACOG) (approximately 2% of membership). CARN members were sampled to demographically represent ACOG. RESULTS: Of the 606 eligible respondents, surveys were received from 305 (response rate: 50%). Most obstetrician/gynecologists knew that specific actions by pregnant women could reduce the risk of infection. Seventy-nine to eighty-eight percent reported counseling pregnant women about preventing infection from Toxoplasma gondii, hepatitis B virus, and influenza, 50%-68% about varicella-zoster virus, Listeria monocytogenes, and Parvovirus B19, and <50% about cytomegalovirus, Bordetella pertussis, and lymphocytic choriomeningitis virus. The majority reported time constraints were a barrier to counseling, although most reported educational materials would be helpful. CONCLUSIONS: Knowledge was accurate and preventive counseling was appropriate for some infections, but for others it could be improved. Further studies are needed to identify strategies to increase preventive counseling.

New estimates of the prevalence of neurological and sensory sequelae and mortality associated with congenital cytomegalovirus infection.

Congenital CMV is a major cause of neurological and sensory impairment in children. Reliable estimates of the prevalence of permanent sequelae and mortality associated with congenital CMV are needed to guide development of education and prevention programmes and to gauge the financial costs associated with this disease. To calculate such estimates, this review used data solely from studies in which children with congenital CMV were identified through universal screening. Based on 15 studies with a total of 117 986 infants screened, the overall CMV birth prevalence estimate was 0.7%. The percentage of infected children with CMV-specific symptoms at birth was 12.7%. The percentage of symptomatic children with permanent sequelae was 40-58%. The percentage of children without symptoms at birth who developed permanent sequelae was estimated to be 13.5%. The true burden of congenital CMV infection is unclear because data on important outcomes, such as visual impairment, are lacking and follow-up of infected children has been too short to fully identify late-onset sequelae. Therefore, the estimates of permanent sequelae associated with congenital CMV presented here are likely underestimates. Future studies should extend follow-up of CMV-infected children identified through universal screening and include the evaluation of visual impairment.