Serum Methylcobalamin, Folic Acid, and Homocysteine Levels and their Association with Sensorineural Hearing Loss

Abstract Background: Both folic acid and Vitamin B12 deficiencies can cause premature hearing loss directly or indirectly by elevating homocysteine levels. Here, we estimated the Vitamin B12, folic acid, and homocysteine levels in subjects with sensorineural hearing loss and compared it with those with normal hearing. Methodology: Serum Vitamin B12, folic acid, and homocysteine levels were estimated in 83 subjects with sensorineural hearing loss and compared with the 83 normal hearing subjects. Results: Nearly 21.7% had low serum methylcobalamin levels, 61.4% were within normal ranges, and 14 (16.9%) had higher levels. In the control group, 7.3%, 86.7%, and 6% had low, normal, and high levels of methylcobalamin, respectively, which was statistically significant. Folate deficiency was found in 54% and 36% of the enrolled cases and controls, respectively, which was statistically significant. 65.1% of cases and 63% of the control groups had high homocysteine levels, which was not statistically significant ( P = 0.790). There were no statistical differences in cases and control group when age group, gender, and unilateral and bilateral hearing loss were considered except in homocysteine level. Serum methylcobalamin levels decreased as hearing loss worsened. Conclusion: The low serum level of methylcobalamin and folic acid can predispose to sensorineural hearing loss. Males are prone to sensorineural hearing loss, probably due to high homocysteine levels. People with diabetes with high levels of methylcobalamin are also prone to develop hearing loss. We recommend serum Vitamin B12 and folic acid estimation in all cases of sensorineural hearing loss.