Cross sectional study on relationship between plasma homocysteine levels with degree of sensorineural hearing loss

• Main Authors: Raja Lope Ahmad, Raja Ahmad Al'konee, Ayob, Azizi, Wan Leman, Wan Ishlah, Mokhtar, Rafidah Hanim
• Format: Conference or Workshop Item
• Language: English; English; English
• Published: Springer 2007
• Subjects: RF Otorhinolaryngology
• Online Access: http://irep.iium.edu.my/16981/1/Dr_Raja5.European_Archie.Vienna.pdf; http://irep.iium.edu.my/16981/4/SNHL-HCY.EUFOS_VIENNA_2007.pdf; http://irep.iium.edu.my/16981/5/oto-european.pdf; http://irep.iium.edu.my/16981/
• Institution: Universiti Islam Antarabangsa Malaysia

OBJECTIVES: Sensorineural hearing loss (SNHL) is one of common clinical problem presented in daily otological practice. The pathological problems can be either in the cochlea or in the retrocochlear region. Majority of the aetiologies are unknown. The causes have been postulated secondaries to vascular pathology, autoimmune reaction, inflammatory process due to viral or bacterial infection, aging process (presbyacusis), head trauma etc. Nevertheless majority of researchers postulated that compromised cochlear blood flow has been considered to be a principal aetiologic factor causing sensorineural hearing loss. Hyperhomocysteinaemia have been found to be associated with vascular diseases such as cerebral vascular accident, peripheral vascular disease, coronary arterial disease, renal disease and dementia. The fact that homocysteine play an important role in vascular diseases and in the involvement of the pathogenesis of atherosclerotic plaque, there are possibilities that it may have an association with the aetiopathological in sensorineural hearing loss. This association however remained to be established. Currently there were no reported studies pertaining to the association between plasma homocysteine levels with the degree of sensorineural hearing loss. METHODS: This is prospective cross sectional study where all patients (age above 21 years old) who presented to ORL clinic at Tengku Ampuan Afzan Hospital with sensorineural hearing loss, which confirmed via the pure tone audiometry (PTA) will be included. Patients who have hearing loss secondary to trauma, suppurative otitis media and tumor within the cerebellopontine angle region are excluded from this study, including patients who are taking vitamin supplement. Written consent is obtained from the patients. The blood withdrawn from the patients will be analyzed to assess the level of the homocysteine. Apart from that demographic data will be obtained from the patients such as age, gender, race, duration of hearing loss, smoking history, physical activity (especially lack of exercise), medical history eg. hypertension, renal problem, diabetes. Control group will be selected from patient who attending the ORL clinic for other ear, nose & throat problems without hearing problem and medical problem. RESULTS: 85 patients who met the inclusion criteria were recruited along with 38 persons who does not have hearing problem as control for this study. The mean age is 49.1 +/- 14.8. In correlation analysis, there is a positive relationship between plasma levels of homocysteine with the sensorineural hearing loss particularly of the left ear (r=0.338, p<0.01). Majority of the patients were having left sensorineural hearing loss. Table: Clinical characteristics of study participants Patients Controls n (Male:Female) 85 (53:35) 38 (13:25) Age (year) (mean) 49.1 ± 14.8 43.1 ± 14.9 Weight (kg) (mean) 67.4 ± 13.0 62.6 ± 15.6 Height (cm) (mean) 161.2 ± 8.6 158.6 ± 7.8 BMI (kg/m) (mean) 26.1 ± 4.3 25.0 ± 6.3 Insulin (iu/l) (mean) 14.5 ± 12.8 11.5 ± 5.4 Homocysteine (μmol/l) (mean) 9.04 ± 4.0 6.9 ± 1.9** Sensorineural hearing loss of Left ear (dBHL) (mean) 38.65 ± 18.32 14.30 ± 4.30** Sensorineural hearing loss of Right ear (dBHL) (mean) 44.17 ± 23.59 14.30 ± 3.75** **P<0.05 Significant CONCLUSIONS: Higher level of homocysteine concentration is a feature found in patient with sensorineural hearing loss. A positive association found between left sided SNHL and homocysteine concentration further supports this. The result from this study will enable us or other researcher in the future to confirm the possible effect of hyperhomocysteinaemia on hearing loss in animal study. This is important to establish the relationship between the two variables at cellular and molecular level. This study may also have an implication on improvement in medical intervention of sensorineural hearing loss and finally the possible impact on public health preventive measures for sensorineural hearing loss. Key words: Sensorineural hearing loss, homocysteine, presbyacusis