Visceral Fat Area Determined Using Bioimpedance Analysis Is Associated with Hearing Loss

Association between fatty liver disease and hearing impairment in Korean adults: a retrospective cross-sectional study

BACKGROUND

We hypothesized that fatty liver disease (FLD) is associated with a high prevalence of hearing loss (HL) owing to metabolic disturbances. This study aimed to evaluate the association between FLD and HL in a large sample of the Korean population.

METHODS

We used a dataset of adults who underwent routine voluntary health checkups (n=21,316). Fatty liver index (FLI) was calculated using Bedogni's equation. The patients were divided into two groups: the non-FLD (NFLD) group (n=18,518, FLI <60) and the FLD group (n=2,798, FLI ≥60). Hearing thresholds were measured using an automatic audiometer. The average hearing threshold (AHT) was calculated as the pure-tone average at four frequencies (0.5, 1, 2, and 3 kHz). HL was defined as an AHT of >40 dB.

RESULTS

HL was observed in 1,370 (7.4%) and 238 patients (8.5%) in the NFLD and FLD groups, respectively (p=0.041). Compared with the NFLD group, the odds ratio for HL in the FLD group was 1.16 (p=0.040) and 1.46 (p<0.001) in univariate and multivariate logistic regression analyses, respectively. Linear regression analyses revealed that FLI was positively associated with AHT in both univariate and multivariate analyses. Analyses using a propensity score-matched cohort showed trends similar to those using the total cohort.

CONCLUSION

FLD and FLI were associated with poor hearing thresholds and HL. Therefore, active monitoring of hearing impairment in patients with FLD may be helpful for early diagnosis and treatment of HL in the general population.

The Link between Gut Dysbiosis Caused by a High-Fat Diet and Hearing Loss

This review aims to provide a conceptual and theoretical overview of the association between gut dysbiosis and hearing loss. Hearing loss is a global health issue; the World Health Organisation (WHO) estimates that 2.5 billion people will be living with some degree of hearing loss by 2050. The aetiology of sensorineural hearing loss (SNHL) is complex and multifactorial, arising from congenital and acquired causes. Recent evidence suggests that impaired gut health may also be a risk factor for SNHL. Inflammatory bowel disease (IBD), type 2 diabetes, diet-induced obesity (DIO), and high-fat diet (HFD) all show links to hearing loss. Previous studies have shown that a HFD can result in microangiopathy, impaired insulin signalling, and oxidative stress in the inner ear. A HFD can also induce pathological shifts in gut microbiota and affect intestinal barrier (IB) integrity, leading to a leaky gut. A leaky gut can result in chronic systemic inflammation, which may affect extraintestinal organs. Here, we postulate that changes in gut microbiota resulting from a chronic HFD and DIO may cause a systemic inflammatory response that can compromise the permeability of the blood-labyrinth barrier (BLB) in the inner ear, thus inducing cochlear inflammation and hearing deficits.

The association between obesity, diet quality and hearing loss in older adults

BACKGROUND

With the aging population, the prevalence of age-related hearing loss will increase substantially. Prevention requires more knowledge on modifiable risk factors. Obesity and diet quality have been suggested to play a role in the etiology of age-related hearing loss. We aimed to investigate independent associations of body composition and diet quality with age-related hearing loss.

METHODS

We performed cross-sectional and longitudinal analyses (follow-up: 4.4 years) in the population-based Rotterdam Study. At baseline (2006-2014), 2,906 participants underwent assessment of body composition, diet, and hearing. Of these 2,906 participants, 636 had hearing assessment at follow-up (2014-2016). Association of body composition and of diet quality with hearing loss were examined using multivariable linear regression models.

RESULTS

Cross-sectionally, higher body mass index and fat mass index were associated with increased hearing thresholds. These associations did not remain statistically significant at follow-up. We found no associations between overall diet quality and hearing thresholds.

CONCLUSIONS

This study shows that a higher body mass index, and in particular a higher fat mass index, is related to age-related hearing loss. However, whether maintaining a healthy body composition may actually reduce the effects of age-related hearing loss in the aging population requires further longitudinal population-based research.

The evaluation of cochlear functions in Familial Mediterranean Fever

Familial Mediterranean Fever (FMF) is a progressive disease characterized by chronic inflammation, which also has negative effects on cochlear functions and hearing levels. We investigated whether the cochlear functions and hearing levels of FMF patients were different than healthy controls and also evaluated the relationship of hearing levels with the age at diagnosis, duration without treatment, and inflammation and lipid parameters in this study. A total of 60 patients diagnosed with FMF and 48 age, gender and body mass index (BMI)-matched healthy controls were included in the study. The hemogram, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and lipid parameters of the subjects were studied and they all underwent pure tone audiometry and Transient evoked otoacoustic emission tests after an otologic examination. The hearing levels of the FMF group were significantly higher than those of the control group. The TEOAE signal/noise (S/N) ratios were similar in both groups. A positive relationship was present between the audiometric test results and the age, BMI, low-density lipoprotein and triglyceride levels and a negative relationship with the high-density lipoprotein levels. A negative relationship was present between the TEOAE S/N ratios and the age of the patients, duration without treatment, lipid parameters, inflammation markers and the creatinine level. FMF patients are exposed to chronic inflammation and this can influence their hearing levels. The age at diagnosis, duration without treatment, chronic inflammation, unfavorable lipid parameters, and obesity can affect hearing tests negatively.