Risk of hearing loss in patients with fibromyalgia: A nationwide population-based retrospective cohort study

Establishing multifactorial risk factors for adult-onset hearing loss: A systematic review with topic modelling and synthesis of epidemiological evidence

BACKGROUND

This systematic review explores the multifaceted nature of risk factors contributing to adult-onset HL. The objective was to synthesise the most recent epidemiological evidence to generate pooled proportional incidences for the identified risk factors.

METHODS

We conducted an extensive search of electronic databases (MEDLINE, EMBASE, and psychINFO) for studies providing epidemiological evidence of risk factors associated with hearing loss. Topic modelling using Latent Dirichlet Allocation (LDA) was first conducted to determine how many risk factor themes were available from the papers. Data were analysed by calculating the pooled proportional incidence using a meta-analysis of proportions.

RESULTS

From the 72 studies reviewed, six key risk factor themes emerged through LDA topic modelling. The review identified ototoxicity, primarily caused by cancer treatments and antibiotics, infectious diseases like COVID-19, occupational noise exposure, lifestyle factors, health conditions, biological responses, and age progression as significant risk factors for HL. The highest proportional incidence was found with cancer-related ototoxicity at 55.4% (95%CI: 39.0-70.7), followed closely by ototoxicity from infectious diseases at 50.0% (95%CI: 28.5-71.5). This high proportional incidence suggests the need to explore less destructive therapies and proactively monitor hearing function during treatments.

CONCLUSIONS

The findings of this review, combined with the synthesis of epidemiological evidence, enhance our understanding of hearing loss (HL) pathogenesis and highlight potential areas for intervention, thereby paving the way for more effective prevention and management of adult-onset hearing loss in our ageing global population.

Immune-Related Disorders Associated With Ménière's Disease: A Systematic Review and Meta-analysis

OBJECTIVE

To analyze evidence supporting an association between immune-related diseases and Ménière's disease (MD) since it has long been thought to be related to autoimmune disorders and allergies.

DATA SOURCES

We retrieved records from Pubmed, Web of Science, Scopus, and Cochrane Library to identify studies published between January 2002 and October 2022.

REVIEW METHODS

Articles were independently assessed by 2 reviewers and verified by a third reviewer. Published cross-sectional studies, cohort/longitudinal studies, case series, and noncomparative cohort studies were considered eligible for inclusion. We conducted a systematic review and meta-analysis according to a registered protocol on the International Prospective Register of Systematic Reviews and Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Selected studies were classified into 2 groups: epidemiological and genetic association studies. Relative frequencies and odds ratios (ORs) for each autoinflammatory/autoimmune disease or genetic marker reported to be associated with MD.

RESULTS

Fifteen studies from 6 countries met our inclusion criteria. Nine are epidemiological studies and 6 are genetic association studies. The epidemiological studies were used to perform 3 different meta-analyses. Airway allergic disease and autoimmune thyroid disease showed a significant association with MD (OR = 2.27 [2.08-2.48] and OR = 1.35 [1.25-1.46]); while rheumatoid arthritis did not (OR = 0.63 [0.28-1.41]). Other comorbidities also showed a significant association with MD like chronic obstructive pulmonary disease, vitiligo, fibromyalgia, arthritis, and psoriasis.

CONCLUSION

Epidemiological evidence supports an association between MD and immune-related disorders in European and Asian populations, with population-specific effects. The evaluation of thyroid diseases, airway allergic diseases, and other inflammatory diseases should be implemented in the clinical management of MD patients.

The Link Between Empty Sella Syndrome, Fibromyalgia, and Chronic Fatigue Syndrome: The Role of Increased Cerebrospinal Fluid Pressure

The etiopathogenesis of fibromyalgia (FM) and chronic fatigue syndrome (CFS) is not yet elucidated. Hypothalamo-pituitary-adrenal (HPA) axis dysfunction is reflected in the hormonal disturbances found in FM and CFS. Some study groups have introduced a novel hypothesis that moderate or intermittent intracranial hypertension may be involved in the etiopathogenesis of FM and CFS. In these conditions, hormonal disturbances may be caused by the mechanical effect of increased cerebrospinal fluid pressure, which hampers blood flow in the pituitary gland. Severe intracranial pressure may compress the pituitary gland, resulting in primary empty sella (ES), potentially leading to pituitary hormone deficiencies. The aim of this narrative review was to explore whether similar hormonal changes and symptoms exist between primary ES and FM or CFS and to link them to cerebrospinal fluid pressure dysregulation. A thorough search of the PubMed and Web of Science databases and the reference lists of the included studies revealed that several clinical characteristics were more prevalent in primary ES, FM or CFS patients than in controls, including increased cerebrospinal fluid pressure, obesity, female sex, headaches and migraine, fatigue, visual disturbances (visual acuity and eye motility abnormalities), vestibulocochlear disturbances (vertigo and neurosensorial hearing loss), and bodily pain (radicular pain and small-fiber neuropathy). Furthermore, challenge tests of the pituitary gland showed similar abnormalities in all three conditions: blunted adrenocorticotropic hormone, cortisol, growth hormone, luteinizing hormone, and thyroid stimulating hormone responses and an increased prolactin response. The findings of this narrative review provide further support for the hypothesis that moderately or intermittently increased cerebrospinal fluid pressure is involved in the pathogenesis of FM and CFS and should stimulate further research into the etiopathogenesis of these conditions.

Fibromyalgia Patients Are Not Only Hypersensitive to Painful Stimuli But Also to Acoustic Stimuli

Fibromyalgia is a chronic widespread pain syndrome associated with hypersensitivity to nociceptive stimuli. This increased sensitivity of FM patients has been associated with central sensitization of dorsal horn neurons. Increasing evidence, however, suggests that the mechanisms of FM hypersensitivity not only affect pain but include light, smell, and sound. We hypothesized that supraspinal augmentation of sensory input including sound represent a hallmark of FM. We tested 23 FM patients and 28 healthy controls (HC) for sensory augmentation of nociceptive and non-nociceptive sensations: For assessment of nociceptive augmentation we used sensitivity adjusted mechanical and heat ramp & hold stimuli and for assessment of sound augmentation, we applied wideband noise stimuli using a random-staircase design. Quantitative sensory testing demonstrated increased heat and mechanical pain sensitivity in FM participants (P < .001). The sound pressures needed to report mild, moderate, and intense sound levels were significantly lower in FM compared to HC (P < .001), consistent with auditory augmentation. FM patients are not only augmenting noxious sensations but also sound, suggesting that FM augmentation mechanisms are not only operant in the spinal cord but also in the brain. Whether the central nervous system mechanisms for auditory and nociceptive augmentation are similar, needs to be determined in future studies. PERSPECTIVE: This study presents QST evidence that the hypersensitivity of FM patients is not limited to painful stimuli but also to innocuous stimuli like sound. Our results suggest that abnormal brain mechanisms may be responsible for the increased sensitivity of FM patients.