Relationship between vestibular alterations and cognitive performance in adults and older adults.

Everyone was assessed on a single occasion, so the study cannot tell whether the vestibular problem came first, whether the cognitive difference did, or whether something else such as age explains both. Only 60 people were studied, and the findings rest on very small subgroups: 11 with an abnormal vHIT and nine with a positive Dix-Hallpike. The authors themselves say the convenience sample limits how far the results can be generalised. Many cognitive areas were compared between groups. Some of the significant results are likely to be chance findings, and the paper does not describe adjusting for the number of comparisons. Participants were all relatively well educated, had normal hearing, and were free of dementia, stroke, ADHD and psychiatric medication. Many patients in a routine balance or memory clinic would have been excluded from this study, so its results may not describe them. Cognitive scores were compared against the test manual's norms rather than against a local group matched for age and education.

The authors declare no financial support for the work and no conflicts of interest.

Do not read this as evidence that vestibular problems cause cognitive decline, or that treating them will improve thinking and memory. Everyone was measured once, the study found the two problems occurring together, and older age on its own was linked to poorer memory. A shared cause, including age, has not been ruled out.