Paroxysmal positional vertigo: the role of age as a prognostic factor.

Aim of this study was to examine possible relationships between several clinical aspects of paroxysmal positional vertigo and factors better defined as "intrinsic" to the patient, above all age. The disorder can affect essentially all age groups; nevertheless, the onset of age-linked degenerative processes, such as vascular damage, can have a negative influence--at least in theory--on the pathogenic mechanisms of cupulolithiasis or canalolithiasis. The study was based on the review of 566 patients with the typical form of paroxysmal positional vertigo. Based on age, the patients were divided into two groups, respectively < or =50 years and > 50 years. For the purposes of this study, a series of clinical-laboratory conditions associated with the risk of, or clear, vascular damage were also considered. The results indicate that if there are no clinical or case-history elements that can be attributed to an aetiological hypothesis, the clinical behaviour of paroxysmal positional vertigo is not affected by the age factor. However, the existence of generic vascular damage, hypothesised by the presence of the above-mentioned conditions, influences certain clinical aspects of the disorder, particularly recovery time, the trend of the active phase and the number of relapses. In conclusion, paroxysmal positional vertigo with a presumed vascular aetiology, the incidence of which increases with age, presents a worse prognosis, not only with respect to the "idiopathic" form in childhood but also the "idiopathic" type in the elderly. The lithiasic model responds well to pathogenic interpretation requirements, which envisage macular degeneration with a vascular component. However, the observation, via imaging, of diffuse ischaemic lesions in critical areas of the brainstem and the cerebellum in many "vascular" patients, does not exclude the possibility of alternative pathogenic mechanisms that, in the final analysis, can lead to compromised VOR on a central level.