Association between otoconia and bone turnover - New methods for diagnosis and classification of BPPV

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K16914
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 56050:Otorhinolaryngology-related
• Research Institution: National Center for Geriatrics and Gerontology
• Principal Investigator: Nakada Takafumi 国立研究開発法人国立長寿医療研究センター, 病院, 外来研究員 (00804048)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 良性発作性頭位めまい症 / 半規管結石症 / クプラ結石症 / ビタミンD / 骨代謝

Outline of Final Research Achievements

Benign paroxysmal positional　vertigo (BPPV) is the most frequent diagnosis among especially in elderly people. Patients with BPPV can have vitamin D deficiency, which is a cause of abnormal bone turnover.
The 10-year major osteoporotic fracture risk was 20.4% for BPPV patients and 14.3% for
controls(p = 0.0069). The 10-year hip fracture risk was 9.0% for BPPV patients and 5.0% for controls(p = 0.0202). The frequency of BPPV increases with age, and it occurs among patients at high risk of fracture. Older adults with dizziness and vertigo should be evaluated for fracture risk. Moreover, we compared serum levels of vitamin D between canalolithiasis and cupulolithiasis of the horizontal canal. The mean 25(OH)D serum level in patients with canalolithiasis and　cupulolithiasis was 13.2 and 20.4 ng/mL, respectively, and the difference　was statistically significant (p= 0.0014). The results will contribute to explain the pathophysiological difference between them.

Free Research Field

めまい平衡医学

Academic Significance and Societal Importance of the Research Achievements

日本は世界一の高齢大国であり、高齢者の健康維持は重要な課題である。
高齢者に最も多いめまい症である良性発作性頭位めまい症（BPPV）は、転倒外傷の原因となるが、そもそも骨代謝障害が発症に関係すると考えられている。本研究では、高齢女性のBPPV患者では１０年内の骨折発生の危険性が有意に高いことを明らかにした。高齢者の骨折はADL低下に繋がる。BPPVを予防することがADLの低下を防ぐことに寄与しうることを示した。また骨代謝障害と関連する血中ビタミンD濃度が、BPPVの亜型で異なることを示した。病態解明や、診断、発症の予防に繋がる研究であり、今後健康長寿に寄与するものと考える。