Hearing impairment does not just happen, certain factors are responsible for it. Wax in the ear is the most common cause of mild to moderate hearing loss.
Recently, the Lagos State Commissioner for Health, Dr. Jide Idris, disclosed that no fewer than 12 million Nigerians, out of the projected figure of 180 million, have hearing defects.
Idris, who disclosed this when the Committee of Wives of Lagos State Officials (COWLSO) donated two transport incubator ambulances to Gbagada General Hospital, and Lagos Island Maternity, as part of their health intervention project, added that hearing loss has adverse socio-economic effects on both adults and children, even as it affects learning and socialisation management.
An ear, nose and throat (ENT) consultant as well as head and neck surgeon and lecturer, College of Medicine, University of Lagos, Dr. Chinyere Nkiruka Asoegwu, allayed people’s fears on the 12 million figure when she said majority in that number would have mild or moderate hearing impairment.
“Twelve million, yes, but the good thing is that when you put all the figures together, majority will have mild or moderate hearing impairment. The bad ones, which are severe profound, can actually be referred to as deafness. What we, ENT doctors, call deafness is severe profound hearing loss because those are social inadequate hearing. Those ones cannot communicate using their ear. They communicate looking at people’s lips,” she said.
Asoegwu described hearing impairment as a reduced perception of sound, meaning any reduction at all in the perception of sound is hearing impairment. She explained that the normal sound level is between zero and 25 decibels; anything beyond that level amounts to hearing impairment.
On the prevalence rate of the problem, she said: “The prevalence rate of hearing impairment is usually very difficult to determine in Africa because we usually don’t have data, but hearing loss is usually part of most congenital conditions associated with newborn babies. So, it is usually included in most syndromic conditions, and it is usually a very common condition.”
On the classification of hearing loss, she said it could be considered from the angle of severity, in which case it could be mild, moderate or severe profound.
Classes of hearing loss
“The good thing, like I said, is that majority are in the mild, moderate; the severe, profound is about 10 to 20 per cent of those that have hearing impairment. That is one level of classification,” she said, noting that another classification could be hinged on the type of hearing loss, which largely depends on where the problem lies. Asoegwu explained that the ear is divided into the outer, middle and inner ear and if the problem is in the outer part, it is called conductive hearing loss: “It is called conductive because the outer and middle ear only conduct sounds. But, if it is beyond the middle ear, we say it is sensory-neural because, in the cochlea, sound is changed to an electrical activity. Then the neuron, which is the nerve, carries it from there.
“So, problems in the inner ear will give you sensory-neural. That is another type of classification, whether it is conductive or sensory-neural. Sometimes, it can be mixed hearing loss, meaning that such a person has both conductive and the sensory-neural hearing loss.”
She said it could also be classified into pre-lingual or post-lingual hearing loss, depending on when the person developed the problem.
“Post lingual, the person talks because the hearing loss occurred after the person had developed speech ability. That is why you see some deaf people who talk. It happens because they became deaf after they had developed speech. But, if it is prelingual hearing loss and it is severe, such a person will not have any speech because you need to hear to be able to develop speech. It is what you hear that you say. That is another classification,” she said.
Asoegwu went further to put the classification into unilateral or bilateral, saying, “If you lose hearing in one ear, the World Health Organisation (WHO), recognises that you have some deficiency. That is because you will not be able to know where sound is coming from. So, when you lose hearing in one ear, it becomes unilateral, but when it affects both ears, it becomes bilateral. So, there are so many classifications of hearing impairment, but these are the common ones,” she submitted.
Twelve million Nigerians with hearing loss is quite large; does it have any implication on the economy of Nigeria? Asoegwu responded, saying, “Hearing is a form of communication and it is the most natural way of communication. The implication is that children who have such a problem are kept at home instead of sending them to special schools for the deaf. And, 80 to 90 per cent of the children who are born with congenital hearing loss have parents who hear. What it simply means is that the parents have no clue of what to do with the children. First of all, they deny and then they take them to churches or mosques, looking for healing and miracles, while time is going. So, the children do not go to school; they are registered late in school; they have high school drop-out rate and, of course, if they don’t finish, what is the probability that they will get jobs?
“Socially, they are discriminated against. There are adults who cannot even support themselves because they don’t have jobs; some of them didn’t even learn any trade. Economically and socially, they are not viable and that is the greatest implication.”
Hearing impairment does not just happen, certain factors are responsible for its occurrence. On the most common causes of the problem, Asoegwu said there are different factors, even as they also depend on the type of hearing loss. She identified wax in the ear as the most common cause of mild to moderate hearing loss.
However, she said factors responsible for hearing loss could be congenital or acquired, genetic or non-genetic and syndromic or non-syndromic: “Congenital means that one is born with it, but acquired means something that happened after birth. Even the congenital can be genetic or non-genetic. Genetic means that it is in the genes, and it is hereditary, while non-genetic means that it is not hereditary. Genetic again can also be syndromic or non-syndromic. Syndromic affects multiple systems and the ear is part of them. Non-syndromic means that the person is totally okay but cannot hear.”
Elaborating on acquired hearing loss, she said: “It can even come from people who are born through difficult deliveries, and if they don’t breath for a few minutes after birth it leads to cerebral palsy. That is not genetic, it is acquired because that child was completely okay until at the point of birth. Even premature births have high percentage of hearing loss in them. So, there are so many things. Like I said, in the acquired, the common hearing loss is usually mild to moderate; then the commonest cause of that would be wax and infection; infection of the outer and middle ear, which leads to discharge. Hole in the ear, that is, perforation of the eardrum, equally means that the whole sound is not collected by the eardrum.
“So, in summary, wax, infections like otitis, traumatic perforation as well as drugs, among others, will lead to hearing loss.”
Also speaking about the development, the medical director of Hosanna Hospital, Festac Town, Lagos, Dr. Chikodi Onyemkpa, agreed that 12 million was quite a large, scary number, but the enormity of the number seems to have been downplayed by the country’s estimated population, which is in the region of 200 million.
On the effects of such development on the Nigerian economy, he said: “Strictly, productivity is directly affected. Can you figure out the import of that on learning? If you have a child that has hearing impairment, learning is difficult, so the future of that child and, by extension, the nation, is impaired.”
“Think of issues about safety. Hearing is one of the five senses on which man depends to preserve life itself. So, safety of individual and that of the entire nation is impaired. Think of a hearing-impaired person standing on the side of the road, who does not hear the car honking, or by the rail line and he doesn’t know that a train is coming; he is dead.
“Apart from his own personal safety, he could be in charge of the safety of other persons and because he could not hear a warning signal to help him to keep others safe, every other person perishes because of his hearing impairment. And, some other people are also put in danger because of his hearing impairment.
“You know how it is, people that don’t hear very well tend to raise their voices when they talk because they think every other person has the same problem.
“I am hardly able to sit in my own church because the speakers are too loud for me and, when I protest, the people that operate the equipment say they need the sound to come up so that they can hear. I said, well, you lose me because, by the time you are hearing, my own ears are hurting. So, when people that have hearing impairment are in charge of certain duties, they also impinge on the wellbeing of other people.
“In summary, these 12 million people have other people whose health they affect; so, there might be a multiplier effect. The development has other health implications. It has learning implications and implications on productivity and the entire economy. It is no joke at all,” he said.
He also attributed the causes to a number of factors, ranging from excessive sound to accidents or self-inflicted injuries as well as infections: “Another common practice in our environment is the misuse of medicines and poisonous substances. We have a very weak control of the use of such drugs and substances, so people are exposed to their use and they damage people’s hearing organs. So, there are different sources of acquiring hearing impairment.”
Offering more insight into the kinds of medicines that are likely to cause hearing impairment, Onyemkpa said: “Medical doctors are very well aware that there are medicines that have effects on the ear and, when they prescribe, they have that at the back of their minds in terms of dosage, how long they are exposing people and who qualifies to take such medicines.
“Some simple antibiotic injections that are out there in town can damage the ear. Some tablets out there in town have effects on the ear, even anti-malaria medicines like quinine, and they are all out there. But, a properly trained doctor knows. Again, due to poor control, people easily access the medicines, since doctors are expensive.”
Although Onyemkpa agreed that hearing impairments that are congenital might not have easy solution, he argued that those caused by man’s activities could be put under check. He said: “Information and information management; public education and health awareness are key factors. If the person that is operating musical equipment knows that, at a certain level, the music he is producing is no longer producing pleasure but sickness, he will be able to modulate the sound. Interestingly, manufacturers of a number of these sound systems have already shown that there is a level of sound the equipment will produce and it will produce sickness instead of pleasure. So, if you look at the equalizer, you will see that when sound is being produced, there are green and red lines. At that red level, it is telling you that it is no longer safe, but the people that use the equipment don’t give a damn.
“Again, that is where people should use ear mufflers to muffle the sound. I have had to walk up to a pastor to ask him who the loudspeaker that was facing the road was meant for. Yes, it is called public address system but which public are you addressing – the one inside the church or the one on the road? If you are addressing those inside the church, your speaker should be facing inside your church, if you are addressing the ones outside the church, who told you they want your loud noise? Look at the neighbourhood; these are residential houses. People are in their houses to rest and not to listen to you. If they want to listen to you, they will come into the church. If you place your programme on radio or television, they will tune to the station and listen to you if they want. What you are doing is that you are abusing them because you have the privilege of having a loudspeaker.
“It is this education that is very important in steering people away from that. And the other issue is also people understanding issues of legal rights. When you have your big generator you want to enjoy yourself, good luck, but I also have a right of sharing that neighbourhood with you without my own right being trampled upon. So, your big generator needs a muffler so that the fact that you become rich doesn’t mean that the rest of us should run away from the neighbourhood. When you go to buy a generator, there is what is called sound-proofing. Soundproof your generator so that the noise will not damage the ears of those of us that live around you.
“Then, the issue of control; regulators should stand up to the duty for which government pays them salary. Nigeria is one of the few countries where people access medicine with ease. When you cross our borders to neighbouring small countries, you can’t access medicine without proper prescription from a doctor. But, in Nigeria, the 180 million people we are talking about can just walk into any shop and buy any medicine they want without a doctor’s prescription; it is a shame, really. Many of our people think it is in their favour, but it is really a shame because medicines, fundamentally, are poisons served in small doses. Those that have adequate training know that every medicine has a downside (side effect). So, every time you are prescribing medicine, you owe your patient that protection of checking whether the medicine will harm him or not.”
Living with hearing impaired persons
Rotimi Kayode has an 18-year-old son, who is deaf and dumb. Ondo State-born Kayode, who lives in Okota, Lagos, said though his son is 18 and ordinarily ought to have finished his secondary education, he is still in junior secondary school.
He told Daily Sun that he did not even know where to start narrating what he and his family have gone through because of his son’s hearing condition.
However, he tried to sum up his experiences, when he said: “I can only say that God who gave him to me knows why, and I am not even regretting anything despite the fact that it is not an easy task. The only thing is that you just have to learn sign language by force because that is the only means of communication.
“It has a lot of downsides. The person would not start school when his mates are starting because of his condition. Special schools for them are very few in Nigeria and, sometimes, not within the reach of many who may be in need of such schools for their wards.
“In my own case, I had to send him to a regular school, and you know what that means. He would have to compete with people whose hearing is perfect. Without being told, you know what the outcome would be.
“Even in behaviour, it affects them. They tend to behave abnormally and that is simply because they respond to only what they see.”
When pressured to describe other difficulties he and his household have faced in the course of bringing up their son in the last 18 years, he said such detailed narration would not be necessary, as it would amount to one questioning God and not being grateful for the precious gift of a child. He, however, submitted that it has not been easy living with a hearing- impaired son.
More Nigerians at risk
Both Asoegwu and Onyemkpa posited that the lifestyles of Nigerians predispose many people to situations that cause hearing loss. They advised for a change in lifestyle, particularly avoiding long exposure to excessive sound, or drastically reducing such practice for those who can’t avoid it, even as they advised that government should wake up to its responsibility, in terms of regulation of access to drugs and consumption, as well as checking noise pollution.
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