Positional nystagmus in patients with chronic dizziness
- 1 Department of Neurology, Hiratsuka Kyosai Hospital, Hiratsuka, Japan
- 2 Department of Neurology, Yokohama City University School of Medicine, Yokohama, Japan
- Dr K Johkura, Department of Neurology, Hiratsuka Kyosai Hospital, 9-11 Oiwake, Hiratsuka 254-8502, Japan;
- Received 22 February 2008
- Revised 10 May 2008
- Accepted 16 May 2008
- Published Online First 11 June 2008
Background: In elderly people, chronic dizziness is endemic. However, chronic dizziness of unknown origin is difficult to assess.
Objective: To investigate whether mild unrecognised benign paroxysmal positional vertigo (BPPV) is a cause of isolated chronic dizziness in the elderly.
Patients and methods: The prevalence of extremely weak, horizontal, direction changing apogeotropic positional nystagmus (HAPN) that had not been detected by conventional examination was evaluated in 200 patients with isolated chronic dizziness and in 155 age matched control subjects without dizziness.
Results: A high prevalence of weak HAPN was found in patients with isolated chronic dizziness (98/200 (49.0%)) compared with the prevalence in control subjects without dizziness (25/155 (16.1%); p<0.0001). Symptoms improved in some patients by daily positional exercise for BPPV.
Conclusion: Because BPPV is the most common cause of dizziness in the elderly, and HAPN is a characteristic of horizontal canal BPPV, our findings suggest that mild persistent BPPV is a possible cause of chronic dizziness of otherwise unknown origin in the elderly.
Funding: This research was supported by grants from the Federation of National Public Service Personnel Mutual Aid Associations and the Okinaka Memorial Institute for Medical Research (to KJ).
Competing interests: None.
Ethics approval: Ethics approval was obtained.