Status of Orofacial Clefts in National Capital Region (NCR), Philippines A Literature Review of Prevalence, Classifications and Risk Factors

Background The Philippine Oral Cleft Registry was initiated by the University of the Philippines-Institute of Human Genetics in 2004. The Registry is expected to provide information on the problem of orofacial clefts (OFCs) and common birth defects of complex etiology resulting from various interactions of genetics and environmental factors in the country. With the increase in the population in the National Capital Region (NCR) and parallel increase in life expectancy, the number of people living with OFCs will continue to increase, along with poverty in the country.Objectives This study aims to investigate the prevalence, identify the types and discuss risk factors for OFCs in the NCR of the Philippines.Study Design and Methods A literature review was conducted using PubMed, Web of science, Web of Knowledge, Web of Science and Cleft Palate Craniofacial Journal for the prior 20 years. The key words "cleft palate," "prevalence," "incidence," "cleft lip," "epidemiology", "NCR" and "Philippines" were used. In addition, a combination of the following terms was also used: "incidence and cleft lip," "incidence and cleft palate," "cleft lip and Philippines," "cleft palate and Philippines,", "incidence of cleft lip and palate and Philippines" and "epidemiology of cleft lip and palate in the Philippines". Some annual reports, and case reports from NGOs which provide free surgeries for cleft lip and/or palate patients in the Philippines were also included. The relevant populations excluded were as follows: clinical features and cleft patterns, reports on etiology, social impact or unoperated without mention of incidence rates of OFCs.Results Ten studies met the criteria of this study. There were two clinical, epidemiological studies of CLP in relation to the Filipino population in the country and Hawaii, and the prevalence of CLP was 1.94 per 1000 live births. The numbers of types of cleft cases were reported based on the Philippine Oral Cleft Registry during a 6 month pilot operation in 2000, wherein 1648 data were gathered. Fifty percent had both cleft lip and palate, 18.4% had cleft lip only. Cleft palate only was found in 15.6%. In the sex ratio according to different studies, males were more commonly affected by various kinds of oral clefts than females. In previous studies, the classification systems were basically based on known etiology from chromosomal analysis, gene mapping, gene linkage combined with morphological and pathological characteristics. However, the syndromic, multiple and isolated groups were not specified and remained undocumented. As to maternal characteristics of the three studies, poor vitamin B-6, plasma zinc and folate status were common in mothers of children with OFCs in the central and southern rural areas in the Philippines. As to the candidate gene associations, the candidate novel region (8p11-23) of the fibroblast growth factor receptor 1 (FGFR1) genes may contribute to syndromic as well as nonsyndromic OFCs. On the other hand, there were differences in the frequency of dermatoglyphic fingerprint pattern types and patterns of dissimilarities between individuals with OFCs. The unaffected relatives were assessed in relation to the genders of case and control groups. It seemed that female subjects were majorly affected. Annual reports of international volunteer medical services in 2005 revealed that the Philippines Band of Mercy (PBM) had in total 543 CLP patients treated and 88 other patients with disorders such as craniosynostosis, eye diseases, hydrocephalus and meningocele in the NCR. In overall annual reports of Operation Smile (OS) from 2007 to 2008, a total of 1478 of CLP patients were treated among 2154 who had physical examinations. However, among 1941 subjects examined 1204 CLP patients were treated in 2009.Conclusion Using various methodologies to identify the etiologies in certain population areas of OFCs in the past two decades in the Philippines, some nutrition inadequacies such as vitamin B-6, folate and zinc concentrations could contribute to increasing the risk of OFCs among reproductive age women. It is important for developing new intervention and prevention services of OFCs such as neonatal screening and family counseling to ensure appropriate education and public awareness. These findings suggest that public health planners and policy makers need to improve and establish guidelines and treatment plan specifically for OFCs.