Sensorineural hearing loss among type 2 diabetic patients and its association with peripheral neuropathy: a cross-sectional study from a lower middle-income country

Abstract

Introduction Despite potential links between diabetes and sensorineural hearing loss (SNHL), routine hearing assessments for diabetic patients are not standard practice. Our study aimed to investigate the prevalence of SNHL and its association with diabetes-related factors among patients with type 2 diabetes mellitus (T2DM).Research design and methods This cross-sectional study was conducted at the Diabetes Clinic, Jinnah Postgraduate Medical Centre, Karachi, Pakistan, from May to September 2021. A total of 396 patients fulfilling the inclusion criteria participated after informed consent. Data collection involved a sociodemographic profile, Michigan Neuropathy Screening Instrument examination followed by pure-tone audiometry and laboratory tests including haemoglobin A1C (HbA1c). HL was defined using better ear four-frequency pure-tone average of ≥26 dB HL and graded as per WHO criteria. Statistical analyses were performed using SPSS. χ2, independent t-test and multinomial logistic regression analyses were applied. P<0.05 at 95% CI was considered significant.Results Our study revealed a high prevalence of SNHL among patients with T2DM. Mild HL was seen in 55.8%, while 18.7% suffered from moderate HL. Common audiological symptoms included difficulty understanding speech in noisy surroundings (44.2%), balance problems (42.9%), sentence repetition (35.9%), tinnitus (32.3%) and differentiating consonants (31.1%). Hearing impairment predominantly affected low (0.25–0.5 kHz) and high (4–8 kHz) frequencies with a significant difference at 4 kHz among both sexes (t (394)=2.8, p=0.004). Peripheral neuropathy was significantly associated with SNHL on multinomial logistic regression after adjusting with age, sex, body mass index and the presence of any comorbidities. Diabetes duration, HbA1c or family history of diabetes was found unrelated to SNHL severity.Conclusions The study highlights the substantial prevalence of SNHL among patients with T2DM and emphasises the importance of targeted audiological care as part of a holistic approach to diabetes management. Addressing HL early may significantly improve communication and overall quality of life.