Risk factors for dizziness in people aged over 50: cross-sectional and prospective data analysis

Dizziness is a common health concern for older adults affecting up to 30% of people aged 65 years and over. Dizziness can be debilitating and significantly diminish quality of life and lead to depression, falls and functional disability. With population ageing, the burden of dizziness on health care systems will increase significantly. It is important, therefore, to better understand factors that predispose older people to this condition.The aims of this thesis were to identify key medical, physical and psychological factors associated with dizziness in two complementary cohorts: (1) 339 community-dwellers aged 75 years and older recruited through the electoral roll; (2) 313 people aged 50 years and older who experienced at least one significant dizziness episode in the past year. Participants completed questionnaires related to dizziness episodes, demographics, health and psychological well being. They also underwent assessments of sensorimotor function, vestibular function, dynamic balance, gait and cardiovascular health. Relationships between dizziness and these factors were then explored in both samples.In the general sample, the prevalence of dizziness was 23%. Within this group, participants who reported dizziness in the past year were more likely to also report back pain, motion sickness and fear of falling, than those who did not report any dizziness. Amongst the dizziness sufferers (cohort 2), a multivariate logistic regression analysis revealed that higher physiological fall risk, unilateral vestibular hypofunction and increased anxiety were significantly and independently associated with increased dizziness frequency. 28% of dizziness sufferers reported moderate to severe handicap. Cardiovascular medication use, increased anxiety, a positive test of Benign Paroxysmal Positional Vertigo, and higher physiological fall risk were identified as significant and independent predictors of higher dizziness handicap in multivariate logistic regression analysis. These findings indicate that dizziness is prevalent in older people, with many people with this condition experiencing significant handicap. Dizziness handicap was associated with both physical and psychological impairments. While it is difficult to establish causal relationships among all the associated factors, the significant associations uncovered provide insight into how dizziness affects older people, and information for possible strategies for treating this condition