Audiometry detects hearing loss, but not tinnitus, which is based on subjective tests. Getty Images Around 14% of adults on the planet hear or have perceived sounds in their ears or head that did not come from an external sound source, They represent 740 million people. A dozen European scientists have estimated for the first time the prevalence of this phenomenon, known as tinnitus or tinnitus (from the Latin tinnire, tinkling). Their results, recently published in the medical journal JAMA Neurology, show that these tinnitus are more common with age and that there are no differences between the sexes, but an intriguing regional disparity. This research also highlights that much remains to be known and defined about this sound disorder. Beyond the definition mentioned above (sounds in the ear or brain that do not come from an external source), there are many unknowns to clear up. Tinnitus is almost always a manifestation of another problem, but its etiology is very varied: it can be the result of hearing damage caused by extreme or constant noise, due to a sudden episode of stress, accumulation of earwax or serious pathology, such as any lesion of tumor origin. This variability in associated disorders aggravates and complicates the paucity of data. And you have to start at the beginning: knowing how many people are affected. The epidemiologist at the Mario Negri Institute (Milan, Italy) Carlotta Micaela Jarach is the first author of the study published in JAMA Neurology, whose results she summarizes: “Our estimates indicate that, Globally, one in seven adults report having experienced tinnitus. In the most serious cases, in which the tinnitus significantly interferes with quality of life, the figure is lower: “We have found severe tinnitus in approximately 2% of the population.” That is about 120 million people who survive with intense ringing, sometimes continuous or disabling. “We have found severe tinnitus in about 2% of the population (120 million people)” Carlotta Micaela Jarach, epidemiologist at the Mario Negri Institute (Milan , Italy) To arrive at these percentages, the study authors reviewed hundreds of previous works on the prevalence and incidence of tinnitus published in scientific journals. In the end, they limited the review to a hundred investigations, some national, others regional. They then scaled their results to the world population. So it’s an approximation. Due to the very nature of tinnitus, it will be difficult to know exactly how many people suffer from it. Generally, tinnitus accompanies, precedes or follows hearing loss, hearing loss. Here comes one of the main problems to study and quantify them: there are devices to measure and record this loss, with detailed information on sound intensity and most affected frequencies. But there is no way to record the beeps. They are a subjective feeling, which complicates things. So, to determine the prevalence, you use surveys and you have to trust what those affected say. This has led the authors of the study to be cautious with the data obtained for minors. By age, 14.4% of adults have suffered from tinnitus. The percentage is very similar in minors, 13.6%. This would seem to contradict the connection between hearing loss and aging. But Silvano Gallus, head of the Lifestyle Epidemiology Laboratory at the Mario Negri Institute and co-author of the study, urges caution when evaluating the data from young people. “Our hypothesis is that the way in which the question is posed plays an important role: in the absence of an objective diagnostic tool that can attest to the presence of tinnitus, it is done through the use of validated questionnaires that allow the identification of the possible severity of the condition,” he comments in an email. “When we were looking at the studies done on children, most of the time the existence of tinnitus was investigated with a general question about the presence of whistling or ringing. This, in our opinion, tends to lead to an overestimation, because many children will answer in the affirmative, even if they do not have tinnitus”, he adds. With that exception made, if the child percentage is true, another 325 million affected would have to be added. But the authors of the research insist that the numbers for children are not credible. “The prevalence of tinnitus seems to be similar in both sexes, while it increases significantly with age” Berthold Langguth, professor of psychiatry and psychotherapy at the University of Regensburg (Germany) By segregating the data by age groups in adults, Gallus’ caution is confirmed. Thus, while the prevalence among young adults (18 to 44 years old) is 9.7%, it rises to 13.7% in the middle-aged (44 to 65 years) and rises to 23.6% in the elderly. 65 years old. The differences are magnified in the case of severe tinnitus, whose prevalence among the elderly is up to 20 times higher than among younger adults. All this confirms the progression of prevalence with age. On the other hand, there are hardly any differences according to sex. Berthold Langguth, professor of psychiatry and psychotherapy at the University of Regensburg (Germany) and co-author of the research, comments on these data in a press release: “We have verified that the prevalence of tinnitus it seems to be similar in both sexes, while it increases significantly with age”, adds and one of the leading experts on tinnitus in Europe. For Langguth, “given the aging of the world population, tinnitus will be a growing problem in the future.” The problem is that, beyond adaptation techniques, there are no great pharmacological advances against tinnitus. The authors of this research have also put their data on the map. By continental regions, in Asia, Oceania, North America and Europe they have similar percentages, between 16% and 13%. But the data for Latin America, with 21.9%, and that for Africa, which drops to 5.2%, are not easily explained, beyond the very low availability of statistics and studies for these areas. What this work does show is that the ringing in the ears does not understand social classes. When comparing the incidence with the gross domestic product per capita, they found that both the richest and the poorest suffer from tinnitus. You can follow EL PAÍS Salud y Bienestar on Facebook, Twitter and Instagram.