Sunday 19 / May / 2024
Muscat: Consanguineous marriages - union between two individuals who are related as second cousins or closer - could be the major reason for hearing loss among many hearing impaired people in the Sultanate, health experts and the association of the hearing impaired said.
Oman ranks second after Saudi Arabia in the number of hearing impaired with one estimate suggesting more than 15,000 patients in the Sultanate. Consanguineous marriages are practiced in Oman and several Muslim countries in the region and in South Asia.
“Consanguineous marriages or parents who are related as cousins or second cousins is the prime cause of this disorder,” Yahya Al Barashdi, a member of the Oman Association for the Hearing Impaired, told the Times of Oman.
“Then there are accidents, infections and other causes,” he said. Most of the hearing impaired population in Oman is concentrated in Al Batinah region in the north (5,000) and Muscat (4,000).
Previous studies
There are no new studies on the subject though. Dr Mazin Al Khabouri, senior consultant, ENT, at the Ministry of Health and WHO (World Health Organisation) Consultant on global hearing loss programmes who last surveyed the causes of “severe to profound deafness in Oman’s paediatric population,” found 70 per cent of the hearing impaired children were offsprings of consanguineous marriages while 30 per cent from non-consanguineous unions.
“In those with consanguineous families, 70.16 per cent were first cousins’ marriages, 17.54 per cent were second cousins and 10.86 per centwere from the same tribe,” he told the Times.
He said the study was based on a national retrospective analysis of 1,400 questionnaires on the causes of hearing loss in Omani children, collected from 1986 to 2000. In the total cohort, 45 per cent had other affected family members. The study found that there was a greater chance of other relatives being affected in the consanguineous group as opposed to the non-consanguineous group (29.7 per cent versus 15.3 per cent).
Hearing screening
“In most cases, the affected relative was a hearing impaired sibling (67.8 per cent). We have demonstrated a higher rate of consanguinity among parents of deaf children in Oman and suggested that this indicated a higher frequency of autosomal recessive deafness in this population,” Al Khabouri said.
About Oman’s efforts to address the issue, he said it is among the first nations to undertake UNHS (Universal Newborn Hearing Screening) as a national priority, an initiative launched as part of the national programme about ear care.
“The programme has evolved consistently and has been the main feeder for the Cochlear Implant programme,” he added. A cochlear implant (CI) is a surgically implanted electronic device that offers a sense of sound to a person who is extremely hearing impaired or severely hard of hearing in both ears. “The Omani government, represented by the health ministry, the education ministry and the social development ministry, is committed to help the deaf in all aspects,” Al Khabouri added.
90 per cent coverage
He said the programme has helped in bringing down the age at which Cochlear Implantation can take place. “The National Universal Newborn Hearing Screening programme has achieved close to 90 per cent coverage of hearing screening across all regions. This is short of the ideal which is 95 per cent but is nevertheless encouraging and amongst the best coverage when considered at the national level,” he said.
In another study, he said, 11,400 Omani people of all ages were surveyed to detect hearing disabilities and common ear diseases. It was concluded that 55.3 per thousand of the population had some degree of hearing impairment. The proportion percentage of bilateral deaf was more in males, he said.
According to the WHO, about 360 million people worldwide have disabling hearing losses resulting from genetic causes, complications at birth, infectious diseases, chronic ear infections, the use of particular drugs, exposure to excessive noise and ageing.
About 1.1 billion teenagers and young adults are at the risk of developing hearing losses due to unsafe use of personal audio devices and exposure to damaging levels of sound at entertainment venues, the WHO has said.
The current production of hearing aids meets less than 10 per cent of global needs, the WHO has reported.
