Sociodemographic, health behavioral, and clinical risk factors for anotia/microtia in a population-based case-control study.

OBJECTIVE: Anotia and microtia are congenital malformations of the external ear with few known risk factors. We conducted a comprehensive assessment of a wide range of potential risk factors using data from the National Birth Defects Prevention Study (NBDPS), a population-based case-control study of non-chromosomal structural birth defects in the United States. METHODS: Mothers of 699 infants with anotia or microtia (cases) and 11,797 non-malformed infants (controls) delivered between 1997 and 2011 were interviewed to obtain information about sociodemographic, health behavioral, and clinical characteristics. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were estimated with logistic regression. RESULTS: Infants with anotia/microtia were more likely to be male (aOR, 1.29; 95% CI, 1.10-1.50) and from a multifetal pregnancy (aOR, 1.68; 95% CI, 1.16-2.42). Cases were also more likely to have parents of Hispanic ethnicity (maternal aOR, 3.19; 95% CI, 2.61-3.91; paternal aOR, 2.11; 95% CI, 1.54-2.88), and parents born outside the United States (maternal aOR, 1.29; 95% CI, 1.06-1.57; paternal aOR, 1.92; 95% CI, 1.53-2.41). Maternal health conditions associated with increased odds of anotia/microtia included obesity (aOR, 1.31; 95% CI, 1.06-1.61) and pre-pregnancy diabetes (type I aOR, 9.89; 95% CI, 5.46-17.92; type II aOR, 4.70; 95% CI, 2.56-8.63). Reduced odds were observed for black mothers (aOR, 0.57; 95% CI, 0.38-0.85) and mothers reporting daily intake of folic acid-containing supplements (aOR, 0.59; 95% CI, 0.46-0.76). CONCLUSION: We identified several risk factors for anotia/microtia, some which have been previously reported (e.g., diabetes) and others which we investigate for perhaps the first time (e.g., binge drinking) that warrant further investigation. Our findings point to some potentially modifiable risk factors and provide further leads toward understanding the etiology of anotia/microtia.

Congenital Aural Atresia prevalence in the Argentinian population.

INTRODUCTION: Congenital Aural Atresia (CAA) or microtia is a malformation that results in esthetic and functional problems. There is little information on prevalence, considering that Latin American is the most affected region in the world. OBJECTIVE: To determine the prevalence of microtia, considering the different ethnical structure of the population. METHODS: A retrospective analysis was performed of the clinical reports of newborn infants (public hospitals) in three different regions. RESULTS: The incidence of CAA in Argentina was 1 case per 7500 new births (i.e. 1.3/10,000). Marked differences were found per geographical area. The means were calculated per year by bilateral parametric estimation, according to the ethnical origins of the population. In the Caucasoid area: 02.47/10,000 (±1.2), in the Mestizo area: 03.99/10,000 (±0.0) and finally in the Amerindian area: 20.93/10,000 (±0.1). CONCLUSION: This study shows different incidences according to the demographic features of the population from 1.90/10,000 to 20.9/10,000. This data indicates that CAA is associated with a genetic problem (ethnic differences).

Epidemiologic Assessment of Microtia in Over 23 Million Consecutive United States Births.

PURPOSE: Conflicting data exist regarding the incidence, demographics, and abnormalities associated with microtia. Using a large national cohort database, a comprehensive evaluation of microtia in the United States was performed. METHODS: The Kids' Inpatient Database was reviewed over a 15-year consecutive period. Information regarding patient demographics, comorbidities, postoperative complications, and hospital setting was collected. Statistical tests were analyzed using independent t tests and χ analysis. RESULTS: A total of 23,479,792 births over 15 consecutive years from 1997 to 2012 were included in the study. Microtia was identified in 1563 births. Incidence of microtia was higher in males (P<0.01) and patients of Asian or Hispanic race (P<0.01). Patients with microtia had significantly more congenital anomalies relative to the rest of the population (P<0.01). Specifically, cardiac and genitourinary anomalies were 51 and 19 times, respectively, more likely in microtia patients. Risk of associated congenital anomalies with microtia was highest in female and Black patients. 12.6% of all microtia patients had an associated craniofacial syndrome with a comparable postsurgical course to the nonsyndromic population. CONCLUSION: This study represents the largest national, longitudinal study of microtia allowing for demographic, socioeconomic, and comorbidity commentary. By quantifying relative risk of associated congenital anomalies, it can help inform the type and utility of screening modalities when evaluating microtia patients.

Microtia in a Chinese Specialty Clinic Population: Clinical Heterogeneity and Associated Congenital Anomalies.

BACKGROUND: Microtia is a congenital anomaly of the external ear that can appear in isolation or in association with other congenital anomalies. In this study, the authors identify the prevalence and phenotypes of associated congenital malformations in patients with microtia in a Chinese specialty clinic population. METHODS: Data were collected from 672 patients seen between December of 2014 and February of 2016 in the Department of Auricular Reconstruction at the Plastic Surgery Hospital of Peking Union Medical College. All patients were examined by trained clinicians and classified into one of three grades of microtia. Co-occurring congenital anomalies were detected and recorded. RESULTS: The majority of study participants were male patients (72 percent), and most participants had unilateral microtia (93 percent, 68 percent of whom had right-side microtia). Two hundred ninety-three patients (44 percent) had one or more associated anomalies. The most commonly occurring comorbid malformations were those of the ear, face, and neck (40 percent of all associated malformations); musculoskeletal system (35 percent); and cardiovascular system (11 percent). CONCLUSIONS: These data represent the first detailed and thematic study of microtia and associated congenital anomalies in a Chinese clinical population. Substantial clinical heterogeneity was observed, and the prevalence of comorbid congenital malformations was high. Future studies investigating congenital anomalies associated with microtia are needed to improve understanding of its cause.

Clinical Efficacy of a Modified Nagata Method That Retains the Fascia Pedicle of the Mastoid Skin Flap in Auricular Reconstruction of Chinese Microtia Patients.

The purpose of this study was to search for an enhanced blood supply in the distal edge of the skin at the mastoid area in total auricular reconstruction. The authors modified the Nagata method by reserving a subcutaneous fascia pedicle (diameter, 3 to 5 mm) at the intersection of the point 11 to 13 mm from the residual ear tragus (or tragus projection) and 8 to 10 mm from the lowest point of the residual ear lobe. Compared with the traditional Nagata method group, the modified Nagata method group that retained the fascia pedicle of the mastoid skin flap had higher rates of excellent and good flaps (p < 0.05). Auricular reconstruction with the modified Nagata method, retaining the fascia pedicle of the mastoid skin flap, had a reduced incidence of skin flap necrosis.

Sociodemographic and hispanic acculturation factors and isolated anotia/microtia.

BACKGROUND: It has been observed in several studies that infants with anotia/microtia are more common among Hispanics compared with other racial/ethnic groups. We examined the association between selected Hispanic ethnicity and acculturation factors and anotia/microtia in the National Birth Defects Prevention Study. METHODS: We examined data from mothers of 351 infants with isolated anotia/microtia and 8435 unaffected infants from the National Birth Defects Prevention Study with an expected delivery date from 1997 to 2007. Sociodemographic, maternal, and acculturation factors (e.g., age, maternal education, household income, body mass index, gestational diabetes, folic acid, smoking, alcohol intake, study center, parental birthplace, and years lived in the United States, maternal language) were assessed as overall risk factors and also as risk factors among subgroups of Hispanics (United States- and foreign-born) versus non-Hispanic whites. RESULTS: Compared with non-Hispanic whites, both United States- and foreign-born Hispanic mothers demonstrated substantially higher odds of delivering infants with anotia/microtia across nearly all strata of sociodemographic and other maternal factors (adjusted odds ratios range: 2.1-11.9). The odds of anotia/microtia was particularly elevated among Hispanic mothers who emigrated from Mexico after age five (adjusted odds ratios = 4.88; 95% confidence interval = 2.93-8.11) or who conducted the interview in Spanish (adjusted odds ratios = 4.97; 95% confidence interval = 3.00-8.24). CONCLUSION: We observed that certain sociodemographic and acculturation factors are associated with higher risks of anotia/microtia among offspring of Hispanic mothers.