Overview of Hearing Loss in the Elderly

Special Article - Hearing Loss

Gerontol Geriatr Res. 2020; 6(1): 1040.

Overview of Hearing Loss in the Elderly

Molinier CE*, Gallois Y, Marx M and Fraysse B

Department of Otoneurology-Head and Neck Surgery, Pierre-Paul Riquet University Hospital Center of Toulouse, France

*Corresponding author: Charles-Edouard Molinier, Department of Otoneurology-Head and Neck Surgery, Pierre-Paul Riquet University Hospital Center, France

Received: December 11, 2019; Accepted: January 03, 2020; Published: January 10, 2020


Deafness is a major public health issue worldwide. According to the World Health Organization (WHO), of all diseases it is the 4th leading cause of morbidity. The WHO defines hearing loss as a loss of more than 25dB in the ear with best hearing. Deafness is considered disabling when hearing loss exceeds 40dB in adults and 30dB in children in the best ear. In their March 2019 report, the WHO estimated that more than 466 million people are affected by disabling hearing loss, which is 6.6% of the world population. The vast majority (93%) is adults and the people most at risk are the elderly, since 1/3 of those over 65 years of age are reported to suffer from deafness. The number of people with disabling hearing loss is expected to rise in the future to 630 million in 2030 and over 900 million in 2050 [1].

In addition, the link between deafness and cognitive decline is now corroborated by robust data and is the subject of much research [2-4]. The economic impact of deafness is estimated to be $750 billion per year [5,6].

Adult Hearing Loss

Overview and epidemiology

Strictly speaking, presbycusis or Age-Related Hearing Loss (ARHL) is not a disease but rather a normal aging process involving all the neurosensory structures of the hearing system.

The pathophysiology is complex because it involves several structures and depends on several factors. Damage can be localized at the cochlear, neural and central level. The intrinsic factors involved are mitochondrial alterations, genetic and cellular disorders, micro-vascularization damage due to cardiovascular risk factors (hypertension, diabetes, dyslipidemia), and other systemic diseases. Extrinsic factors are mainly related to exposure to noise, ototoxic drugs and diet.

ARHL is characterized by a decrease in auditory perception and speech comprehension, especially in noisy environments. Despite a normal hearing threshold, some subjects have difficulty understanding speech. This is referred to as a Central Auditory Processing Disorder (CAPD), which is a deficiency in central auditory pathways such as neural transmission, and an extraction deficit in auditory information processing.

The genetics of presbycusis is still poorly defined due to the polygenicity [7]. At present, a genetic examination is not systematically conducted in the context of classical presbycusis.

Screening for hearing loss

There is no universal screening system for adults as hearing loss is currently defined by general practitioners, ENT specialists or hearing aid acousticians on request by the patient or family.

WHO-sponsored awareness days such as World Hearing Day, held on March 3rd each year, provide free screening for patients at participating centers in many countries.

The gold standard in the diagnosis of presbycusis is still tonal and vocal audiometry. Therefore, presbycusis appears to be bilateral symmetrical sensorineural hearing loss that is predominant in high frequencies on tonal audiometry. Speech audiometry identifies difficulties in speech discrimination with an increase in the intelligibility threshold, which corresponds with the dB threshold required to recognize 50% of the words presented(Figure 1).