Abstract
Background
Microtia is a congenital anomaly characterized by malformation of the external ear. The complex chronic conditions (CCC) classification system identifies children with long-standing health problems based on various body systems and disease types. This study utilized the Pediatric Health Information System (PHIS) database to investigate the relationship between microtia and CCCs to guide screening protocols and provide insight into patient-centered treatment.
Methods
A retrospective review of PHIS was conducted between 2015 and 2023. Patients were identified with an initial encounter with an associated microtia diagnosis from all participating hospitals. Patient demographics, associated organ system flags, and CCCs were collected and analyzed. Descriptive statistics were performed and effect sizes were calculated to assess associations between variables and microtia complexity.
Results
A total of 20,313 patients with microtia were identified. Of these patients, 11 183 were male (55.1%), non-Hispanic White (n = 8089, 41.9%), or Hispanic (n = 6512, 33.8%). Nearly 40% of diagnoses were associated with at least 1 CCC (n = 8234), and a significant proportion (n = 5715) were noted to have 2 or more CCCs. Cardiovascular diagnoses were among the most common organ system affected (16.8%), followed by gastrointestinal conditions (15.4%).
Conclusion
This study highlights a significant correlation between microtia and CCCs. With 40% of patients diagnosed with microtia also presenting with at least 1 CCC, this study underscores the importance of comprehensive medical assessment and care strategies while further supporting the increased correlation of cardiac conditions in this population. This necessitates a re-evaluation of first-line screening modalities for patients presenting with microtia.
Keywords
Introduction
Microtia, a congenital malformation of the external ear, 1 can occur in isolation, in combination with other congenital anomalies, or as part of a broader syndromic condition. Traditionally, emphasis has been placed on microtia's association with renal anomalies,2,3 prompting advocacy for renal ultrasound screenings as part of an initial work-up.4,5 However, more recent studies have highlighted associations with cardiac anomalies.6‐8 Consequently, an associated microtia diagnosis may serve as an indicator of a larger health condition.
In 2000, Feudtner et al. developed the complex chronic condition (CCC) classification system to identify children with serious, long-standing medical conditions that require specialized pediatric care. 9 These conditions often involve multiple organ systems and require ongoing medical interventions that pose a significant burden to the patient, family, and healthcare system. Many of these complex conditions require frequent hospitalizations, multidisciplinary care, and ongoing treatment. 10 While microtia itself does not meet the criteria for a CCC, the diagnosis’ relationship to CCC has yet to be explored.
Leveraging data from the Pediatric Health Information System (PHIS) database, this study provides a comprehensive analysis of microtia and its association with CCCs. Importantly, this study also identifies the prevalence of underlying congenital anomalies in children with microtia and its association with CCC. The results from this study provide new insight into the complexities of microtia, associated diagnoses, and broader healthcare ramifications of this population.
Methods
Data for this study were obtained from the Pediatric Health Information System (PHIS), an administrative database maintained by the Children's Hospital Association (CHA) (Lenexa, KS), that contains inpatient, emergency department, ambulatory surgery, and observation encounter-level data from not-for-profit, tertiary care pediatric hospitals in the United States. For the purposes of external benchmarking, participating hospitals provide encounter-level data including demographics, diagnoses, and procedures. Nearly all of these hospitals also submit resource utilization data (eg, pharmaceuticals, imaging, and laboratory) into PHIS. Data are de-identified at the time of data submission, and data are subjected to a number of reliability and validity checks before being included in the database. For this study, data from 49 hospitals were included, for which over 80% of all pediatric specialty care was delivered in the United States. 11 The pediatric complex chronic condition (V3) classification system is integrated into PHIS and identifies patients with 1 or more CCC categories, including cardiovascular, respiratory, neuromuscular, renal, gastrointestinal, hematologic, immunologic, or metabolic anomalies. 12
Study inclusion criteria included patients presenting with microtia (ICD-10: Q16.0, Q16.9, Q17.2, Q17.3, Q17.4, Q17.8, or Q17.9) at either an inpatient or outpatient encounter between January 1, 2016 and December 31, 2023. PHIS was then queried back to 2004 to abstract relevant data from the patient's first PHIS encounter where microtia was documented (same ICD-10 codes as above, plus ICD-9: 744.00, 744.01, 744.22, 744.29, or 7443). As such, each patient in the study is unique, with their associated data pertaining to their “index” encounter. Patients were excluded if they were 21 years or older at the time of the index visit. Standard patient-level demographic data were collected (eg, age, gender, ethnicity, payor type, etc), as well as index encounter clinical characteristics (eg, length of stay, diagnoses, procedures, CCCs, etc). For the purposes of this study, we introduce a new term, “complex microtia,” to distinguish the condition from less complex presentations thereof; complex microtia is defined as the presentation of microtia alongside at least 1 other complex chronic condition, syndromic disorder, or microtia-related congenital anomaly.
Categorical variables were summarized as frequencies and percentages, while normally distributed continuous variables were presented as means and standard deviations (SD) and nonnormally distributed data as medians and interquartile ranges (IQR). Bivariate comparisons were performed with Chi-square tests for categorical variables, t-tests for distributed continuous variables, and Mann-Whitney U tests for nonnormally distributed continuous variables. Cramer's V was also employed to determine the strength of association between specific categorical factors and the presence of complex microtia. All statistical analyses were conducted using Stata 18 MP (College Station, TX) and RStudio (“Chocolate Cosmos” Release, Posit Software).
Results
A total of 20 313 patients were eligible for inclusion in the study, of which 11 183 (55.1%) were male. A little less than half (41.9%, n = 8089) of the patients were non-Hispanic White and 67.3% (n = 13 665) were less than five years of age at the time of their index encounter (Table 1). Nearly 40% (n = 8234) of the population had an associated CCC, with 20.5% (n = 4167) having 3 or more CCCs. Of these, the most common complex chronic conditions were those related to a congenital or genetic defect (n = 4162, 20.5%), a cardiovascular condition (n = 3425, 16.9%), and technology-dependence (n = 3129, 15.4%) (Table 2).
Patient Characteristics at First Microtia Encounter.
Clinical Characteristics.
Characteristics of patients with complex vs. noncomplex microtia are shown in Table 3. Age distribution of presentation of complex microtia was statistically significant, with neonates presenting with complex microtia more than noncomplex cases (43.4% vs 18.8%, P < .001), and noncomplex microtia presenting later in childhood (32.5% vs 15.4%, P < .001). While gender distribution was similar between patients with complex and noncomplex microtia, racial and ethnic differences were statistically significant: Black patients had nearly twice the frequency of complex microtia cases compared to those without (12.1% vs 6.8%, P < .001), while Hispanic patients had slightly more instances of noncomplex vs complex microtia (37.1% vs 30.5%, P < .001). Insurance coverage differed slightly between complex and noncomplex microtia groups, and although most patients were discharged home, the complex microtia group had more cases requiring nursing home care (5.8% vs. 0.4%) and transfers (3.0% vs. 0.1%). The complex microtia group also had a significantly higher median number of diagnoses (13 vs 2).
Complex vs Noncomplex Microtia.
The strength of the association between particular demographic factors and microtia complexity was evaluated by calculating effect sizes (Table 4). There was a moderate association between the age at presentation and complex microtia (Cramer's V = 0.300), while race and ethnicity and payor type showed lower associations.
Effect Size of Complex Microtia.
Cramer's V: <0.2, weak association; 0.2–0.6, moderate association; >0.6, strong association.
Discussion
This study explores microtia and its association with CCCs, revealing insights into the complexity of microtia and its relationship to other conditions. The presented data calls for a comprehensive, multidisciplinary approach for the management of patients with microtia who may benefit from early diagnostic interventions for coexisting conditions. Currently, the first consultation for microtia occurs shortly after birth and involves a multidisciplinary approach to facilitate parent understanding and preparation for future interventions. 13
The presence of microtia in conjunction with other chronic conditions has been noted in previous literature, often emphasizing renal anomalies in patients with external ear malformations.1‐8,10,14‐16 Although renal anomalies have traditionally been a major focus due to their developmental connection with the ear—both originating from the branchial arches and mesoderm—recent studies, including our data, indicate that heart defects may be more common in individuals with microtia than once thought. Congenital heart conditions such as septal defects and conotruncal abnormalities are frequently observed.
In an epidemiologic study based in China, Zhang et al. reported high rates of associated congenital abnormalities, including craniofacial and cardiovascular comorbidities. 2 Similarly, Luquetti et al. noted a high incidence of associated anomalies, emphasizing cardiovascular, renal, and skeletal pathology. 14 Paul et al. and Alexander et al. reinforced the association between microtia and congenital heart disease, highlighting the need for cardiac evaluation in these patients.8,15 In a recent systematic review and meta-analysis published by our team, we found that cardiovascular anomalies were more prevalent than renal anomalies. 10 These findings align with the data presented in this study, showing that there is a higher prevalence of coexisting cardiovascular chronic conditions compared to renal anomalies in patients with microtia (16.9% vs. 8.6%, respectively).
This evolving understanding carries important consequences for clinical evaluation. While renal ultrasound has been the standard first-line screening to detect renal abnormalities in microtia patients, the unexpectedly high rate of cardiac anomalies suggests a need for broader screening measures. Including an echocardiography—especially in moderate to severe cases of microtia—could be beneficial. This approach supports a risk-based model of care, where additional clinical features such as facial asymmetry, cleft palate, or developmental delays warrant a full assessment of both kidney and heart health. Furthermore, in cases where microtia is part of a syndrome such as Treacher Collins, CHARGE, or Goldenhar, cardiac screening with echocardiography may be even more strongly indicated regardless of the severity of the auricular anomaly.
This analysis demonstrates that younger patients (less than 1 year of age) were more likely to have a complex microtia diagnosis compared to older children, indicating early identification and potential resource allocation for comprehensive evaluation in this age group. However, this finding should be tempered given that children with complex chronic conditions are frequently identified earlier in life; it is possible that presentation with microtia was of secondary importance for the index hospitalization. When observing racial and ethnic disparities, the higher prevalence of complex microtia among non-Hispanic Whites and Hispanics is supported by a small effect size (0.106). While this association is statistically significant, the small magnitude suggests that race and ethnicity alone are not primary predictors of microtia complexity.
The distribution across age demonstrated a higher prevalence of complex microtia among neonates and infants, which was reinforced by a moderate effect size. Children with higher complexity require hospitalization earlier in life and have an increased likelihood for subsequent hospitalizations throughout childhood. 9 This finding may be an artifact of sampling bias considering that noncomplex patients may have been diagnosed at the same age without hospitalization. Regarding insurance coverage, the weak effect size between complex and noncomplex cohorts suggested a minimal impact of payor status on the complexity of microtia.
Limitations
This is a retrospective study utilizing an administrative database that is not nationally representative; although this study may provide a more detailed view of patients with microtia than previous studies, it only includes patients from select children's hospitals within the United States that participate in PHIS. Consequently, it does not capture the total pediatric population or accurately estimate the prevalence of microtia nationwide. Additionally, while CHA maintains strict data quality standards and practices, there may be inherent biases in individual hospital data submissions related to documentation inconsistencies and missing data. Furthermore, given the database is curated from aggregated billing data, detailed socioeconomic and other non-billable clinical data may be underreported herein. Despite these drawbacks, this study represents 1 of the largest cohort studies of pediatric microtia in the United States, providing new information for this common facial congenital difference.
Conclusion
This study highlights a significant correlation between microtia and CCCs. With 40% of patients diagnosed with microtia also presenting with at least 1 CCC, this study underscores the importance of comprehensive medical assessment and care strategies for this patient population. This study further supports the finding that cardiac conditions appear to affect this population more than other conditions, necessitating a re-evaluation of first-line screening modalities for patients presenting with microtia.
Footnotes
Abbreviations
Author Note
All financial support is acknowledged in this article. Any commercial or financial arrangements related to this article have been discussed with our Editor, who will advise whether details should be declared. We have not signed an agreement with any sponsor that might compromise the impartial reporting of data.
Ethical Considerations
The Ethics Committee of the Children's Hospital of Orange County waived the need for ethics approval and patient consent for the collection, analysis, and publication of the retrospectively obtained and anonymized data for this non-interventional study.
The study was approved by the Danish Data Protection Agency. According to Danish legislation, neither ethics approval nor patient consent is required for registry linkage studies. This article does not contain any studies with human or animal participants. There are no human participants in this article and informed consent is not required.
Funding
The authors received no financial support for the research, authorship, and/or publication of this article.
Declaration of Conflicting Interests
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Informed Consent
Informed consent for information published in this article was not obtained because this study was IRB exempt. Patient data were taken from a national database.