Study links symptomatic dizziness to higher mortality risk

By Dr. Priyom Bose, Ph.D.Feb 12 2024Reviewed by Benedette Cuffari, M.Sc.

Dizziness is a common complaint associated with multiple causes and resultant morbidity; however, it remains unclear whether symptomatic dizziness is associated with all-cause and cause-specific mortality.

A recent JAMA Otolaryngoly-Head Neck Surgery study assesses the associations between symptomatic dizziness, its various manifestations, and all-cause and cause-specific mortality.

Study: Association of Symptomatic Dizziness With All-Cause and Cause-Specific Mortality. Image Credit: Tunatura / Shutterstock.com

Background

Dizziness has a lifetime prevalence of 15-36% and is a widespread complaint in the general population. As a result, it is associated with more healthcare visits, risk of falls, disability, and hospital admissions. Annually, dizziness accounts for 2.8 million visits to the emergency department.

Dizziness can be caused by benign or severe conditions, the latter of which can include brain tumors and stroke. This wide range of factors contributing to dizziness leads to the non-specific property of symptomatic dizziness, which can present in the form of disequilibrium, imbalance, and lightheadedness. Thus, it is imperative to elucidate the underlying causes of dizziness and the manifestations of health outcomes.

About the study

The current study used a cohort of middle-aged and older United States adults to assess the association between all-cause and cause-specific mortality and dizziness. To date, this association has not been extensively studied in the existing literature.

Data on mortality were obtained from the National Health and Nutrition Examination Survey (NHANES). At an average of 15 years, NHANES is the longest follow-up mortality data that provides insights into the association between all-cause and cause-specific mortality, dizziness, and manifestations.

Individuals 40 years and older who have previously answered questions about symptomatic dizziness within the past 12 months were included in the analysis. The data were analyzed between February and August 2023, with the exposure variable being self-reported symptomatic dizziness.

The primary outcomes included all-cause and cause-specific mortality, the latter of which included mortality due to diabetes, cancer, cardiovascular disease, and unintentional injuries. In the regression analysis, data were adjusted according to demographics and medical history. 

Key findings

The mortality risk was higher among individuals with symptomatic dizziness in the last 12 months, including its manifestations. However, cancer-specific mortality could not be definitively assessed due to the imprecision of the estimates.

When considering diabetes-, cancer-, and cardiovascular-specific mortality, mortality rates risks were higher. Comparatively, mortality risks were not correlated with unintentional injuries. 

For all-cause or any cause-specific mortality, individuals reporting positional dizziness were not associated with higher mortality. Symptomatic dizziness, particularly difficulty with balance or falls, was associated with an increased risk of all-cause mortality, as shown by multivariable Cox proportional hazard models. Symptomatic dizziness without falls or balance issues was not associated with an increased mortality risk.

One novel finding of the current study was the association between diabetes-specific mortality and symptomatic dizziness, which could be due to peripheral neuropathy and microangiopathy-induced ischemic changes in vestibular organs that lead to a sense of imbalance. Importantly, cardiovascular diseases or diabetes may induce dizziness through other mechanisms that do not directly contribute to mortality.

Furthermore, reports of dizziness without falls or balance issues were not associated with higher mortality. Physical examination and follow-up questions related to frequency, duration, and characteristics are essential for patients with symptomatic dizziness. 

Conclusions

Symptomatic dizziness was associated with a higher risk of all-cause mortality and mortality secondary to diabetes and cardiovascular disease. In the United States, reports of symptomatic dizziness are likely to increase as the population continues to age. Thus, future research is needed to identify interventions for the effective management of dizziness and its effect on mortality.

A key limitation of the current study is that the self-reports are dependent on individual respondent interpretation and recall bias. Additionally, the reports were obtained at the time of NHANES participation.

Data on exact dates and changes in status were unavailable, which could have biased the results. For cause-specific mortalities, such as unintentional injury, the underlying causes could be heterogeneous, and a limited number of events may have led to the lack of associations. 

Another limitation is the observational nature of the data, which prevented the establishment of any causal relationships. Questions on dizziness, such as lightheadedness or room-spinning sensation, also lacked clinical meaning.

Despite controlling for major confounding factors and mediators, residual confounding due to other unmeasured factors could not be excluded.