Demographic characteristics of craniosynostosis patients in Asia

Craniosynostosis (CRS) is a congenital condition resulting premature fusion of one or more cranial sutures. CRS is classified according to the involved sutures into sagittal, metopic, unicoronal, unilambdoid, bicoronal, and multiple-suture CRS, with sagittal suture fusion known to be the most common type. Although multiple studies have presented demographic characteristics of CRS patients, to date, there is no study representing an Asian population. We sought to compare the demographic characteristics of Asian patients to those of Western patients, considering previous reports.

A total of 266 CRS patients treated in a single institution from 1996 to 2016 were retrospectively reviewed. Data from the patients was collected regardless of whether they underwent operation. Patients' age at the time of presentation, sex, and maternal and paternal age at birth were reviewed. Patients were routinely investigated for abnormal genes (FGFR2 and FGFR3). The Bayley Scales of Infant Development, Second Edition (BSID-II), was used to assess the patients' cognitive and psychomotor development. One-way analysis of variance or the Kruskal-Wallis test was used to compare continuous variables. A p value of <0.05 was considered statistically significant.

Our study included 157 males (59.02%) and 109 females (40.98%), with an age ranging from 0.1 to 10.5 years. The mean age at the time of diagnosis was 2.01 ± 2.57 years, and the mean age at operation was 2.16 ± 2.61 years. Of the patients, 27 (10.15%) were bicoronal, 28 patients (10.53%) were metopic, 48 patients (18.04%) were unicoronal, 50 patients (18.80%) were unilamboid, and 67 patients (25.19%) were sagittal. Patients with multiple-suture CRS totaled 46 (17.29%). Investigation of abnormal genes revealed six patients (2.20%), including two patients with abnormal FGFR2 and four patients with abnormal FGFR3. Maternal and paternal ages at the patients' birth were 32.18 ± 4.56 years and 34.71 ± 4.72 years, respectively. The mean BSID-II scores were 84.96 ± 22.77 for the Mental Development Index and 84.19 ± 25.62 for the Psychomotor Development Index. To examine the trend of diagnosis of CRS type, we also evaluated the number of new patients diagnosed with nonsyndromic CRS per year at our institution. New diagnoses of CRS generally increased from the year 2009, although variations continued.

The mean age of our patients is relatively high compared to previous, Western studies. Through this research, we recognized that cultural discrepancies regarding the expectations of Asian parents may lead to prolonged diagnosis of CRS patients, and yet even relatively older CRS infants can successfully be treated with surgical intervention. The prevalence of CRS types and BSID-II development scores varied compared to those in previous Western studies. Further investigations at the genetic level are required to compare the different populations. To diagnose CRS in an effective and timely manner, a physician must be aware of the general characteristics and understand the variations between Western and Eastern populations.