Background: In elderly persons, chronic dizziness is endemic. However, chronic dizziness of unknown origin is difficult to assess.
Objective: To investigate whether mild, unrecognized benign paroxysmal positional vertigo (BPPV) is a cause of isolated chronic dizziness in the elderly.
Patients and Methods: We evaluated the prevalence of extremely weak, horizontal, direction-changing apogeotropic positional nystagmus (HAPN) that had not been detected by conventional examination in 200 patients with isolated chronic dizziness and 155 age-matched control subjects without dizziness.
Results: We found a high prevalence of weak HAPN in patients with isolated chronic dizziness (98/200 [49.0%]) in comparison to 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 the 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.