Metabolic syndrome is associated with hearing loss among a middle-aged and older Chinese population: a cross-sectional study.

BACKGROUND:Although the association of metabolic syndrome (MetS) and hearing loss has been evaluated, findings are controversial. This study investigated this association in a Chinese population. METHODS:A cross-sectional study including a total of 18,824 middle-aged and older participants from the Dongfeng-Tongji Cohort study was conducted. Hearing loss was defined as the pure-tone average (PTA) of frequencies 0.5, 1.0, 2.0, and 4.0 kHz >25 decibels hearing level (dB HL) in the better ear and graded as mild (PTA 26-40 dB HL), moderate (PTA >40 to ≤60 dB HL), and severe (PTA >60 dB HL). MetS was defined according to the International Diabetes Foundation (IDF) criteria of 2005. Association analysis was performed by logistic regression. RESULTS:After adjustment for potential confounders, participants with MetS showed higher OR of hearing loss (OR, 1.11; 95% CI: 1.03-1.19). The MetS components including central obesity (OR, 1.07; 95% CI: 1.01-1.15) and hyperglycemia (OR, 1.12; 95% CI: 1.04-1.20) were also positively associated with hearing loss. Low HDL-C levels were also associated with higher OR of moderate/severe hearing loss (OR, 1.21; 95% CI: 1.07-1.36). CONCLUSIONS:The MetS, including its components central obesity, hyperglycemia, and low HDL-C levels were positively associated with hearing loss. Key messages Studies indicated that cardiovascular disease and diabetes might be risk factors of hearing loss. However, few efforts have been made to establish a direct relationship between metabolic syndrome and hearing loss, especially in Chinese population. In the present study, a cross-sectional design using data from the Dongfeng-Tongji Cohort study was conducted to assess the association between metabolic syndrome and hearing loss. The metabolic syndrome, as well as its components central obesity, hyperglycemia, and low HDL-C levels were positively associated with hearing loss.