title: Components of Metabolic Syndrome as Risk Factors for Hearing Threshold Shifts.
abstract: BACKGROUND
  Hearing loss was a common, chronically disabling condition in the general population and had been associated with several inflammatory diseases. Metabolic syndrome, which was associated with insulin resistance and visceral obesity, was considered a chronic inflammatory disease. To date, few attempts had been made to establish a direct relationship between hearing loss and metabolic syndrome. The aim of the present study was to investigate the relationship between metabolic syndrome and hearing loss by analyzing the data in the reports of the National Health and Nutrition Examination Survey 1999-2004.
  
  
  METHODS
  This study included 2100 participants aged ≤ 65 years who enrolled in the National Health and Nutrition Examination Survey (1999-2004). We examined the relationship between the presence of different features of metabolic syndrome in the participants and their pure-tone air-conduction hearing thresholds, including low-frequency and high-frequency thresholds.
  
  
  RESULTS
  After adjusting for potential confounders, such as age, medical conditions, and smoking status, the participants with more components of metabolic syndrome were found to have higher hearing thresholds than those with fewer components of metabolic syndrome (p < 0.05 for a trend). The low-frequency hearing threshold was associated with individual components of metabolic syndrome, such as abdominal obesity, high blood pressure, elevated triglycerides, and a low level of high-density lipoprotein cholesterol (HDL-C) (p < 0.05 for all parameters).
  
  
  CONCLUSIONS
  The results indicated that the presence of a greater number of components of metabolic syndrome was significantly associated with the hearing threshold in the US adult population. Among the components of metabolic syndrome, the most apparent association was observed between low HDL and hearing loss.
authors.affiliation: Department of Family and Community Medicine, Division of Family Medicine, Tri-Service General Hospital; and School of Medicine, National Defense Medical Center, Taipei, Taiwan, Republic of China.
authors.forename: Yu-Shan
authors.initials: YS
authors.lastname: Sun
authors.affiliation: Department of Family and Community Medicine, Division of Family Medicine, Tri-Service General Hospital; and School of Medicine, National Defense Medical Center, Taipei, Taiwan, Republic of China.
authors.forename: Wen-Hui
authors.initials: WH
authors.lastname: Fang
authors.affiliation: Department of Family and Community Medicine, Division of Family Medicine, Tri-Service General Hospital; and School of Medicine, National Defense Medical Center, Taipei, Taiwan, Republic of China; Department of Family and Community Medicine, Division of Geriatric Medicine, Tri-Service General Hospital; and School of Medicine, National Defense Medical Center, Taipei, Taiwan, Republic of China; Graduate Institute of Clinical Medical, College of Medicine, National Taiwan University, Taipei, Taiwan, Republic of China.
authors.forename: Tung-Wei
authors.initials: TW
authors.lastname: Kao
authors.affiliation: Department of Family and Community Medicine, Division of Family Medicine, Tri-Service General Hospital; and School of Medicine, National Defense Medical Center, Taipei, Taiwan, Republic of China; Department of Family and Community Medicine, Division of Geriatric Medicine, Tri-Service General Hospital; and School of Medicine, National Defense Medical Center, Taipei, Taiwan, Republic of China.
authors.forename: Hui-Fang
authors.initials: HF
authors.lastname: Yang
authors.affiliation: Department of Family and Community Medicine, Division of Family Medicine, Tri-Service General Hospital; and School of Medicine, National Defense Medical Center, Taipei, Taiwan, Republic of China.
authors.forename: Tao-Chun
authors.initials: TC
authors.lastname: Peng
authors.affiliation: Department of Family and Community Medicine, Division of Family Medicine, Tri-Service General Hospital; and School of Medicine, National Defense Medical Center, Taipei, Taiwan, Republic of China; Department of Family and Community Medicine, Division of Geriatric Medicine, Tri-Service General Hospital; and School of Medicine, National Defense Medical Center, Taipei, Taiwan, Republic of China.
authors.forename: Li-Wei
authors.initials: LW
authors.lastname: Wu
authors.affiliation: Department of Family and Community Medicine, Division of Family Medicine, Tri-Service General Hospital; and School of Medicine, National Defense Medical Center, Taipei, Taiwan, Republic of China; Department of Family and Community Medicine, Division of Geriatric Medicine, Tri-Service General Hospital; and School of Medicine, National Defense Medical Center, Taipei, Taiwan, Republic of China.
authors.forename: Yaw-Wen
authors.initials: YW
authors.lastname: Chang
authors.affiliation: Department of surgery, Division of plastic surgery, Tri-Service General Hospital; and School of Medicine, National Defense Medical Center, Taipei, Taiwan, Republic of China.
authors.forename: Chang-Yi
authors.initials: CY
authors.lastname: Chou
authors.affiliation: Department of Family and Community Medicine, Division of Family Medicine, Tri-Service General Hospital; and School of Medicine, National Defense Medical Center, Taipei, Taiwan, Republic of China; Department of Family and Community Medicine, Division of Geriatric Medicine, Tri-Service General Hospital; and School of Medicine, National Defense Medical Center, Taipei, Taiwan, Republic of China; Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan, Republic of China.
authors.forename: Wei-Liang
authors.initials: WL
authors.lastname: Chen
mesh_terms: D000328:Adult; D000368:Aged; D001299:Audiometry; D001309:Auditory Threshold / Q000502:physiology*; D001794:Blood Pressure; D005260:Female; D034381:Hearing Loss / Q000209:etiology; D006801:Humans; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications / Q000473:pathology*; D008875:Middle Aged; D009749:Nutrition Surveys; D056128:Obesity, Abdominal / Q000150:complications; D012044:Regression Analysis; D012307:Risk Factors; D014280:Triglycerides / Q000097:blood
chemical_list: D014280:Triglycerides