COLUMBIA, SOUTH CAROLINA – A pioneering study spearheaded by researchers at the University of South Carolina (USC), in collaboration with other institutions, has unveiled a compelling association: older adults who demonstrate superior physical function are significantly more likely to maintain better hearing sensitivity. This revelation, published recently in the esteemed journal Scientific Reports, challenges long-held assumptions about the primary drivers of age-related sensory decline, particularly the role of cardiovascular factors like systolic blood pressure. The findings suggest a more direct and independent link between an active lifestyle and auditory health, offering new avenues for preventative strategies against hearing loss in the aging population.
The cross-sectional study meticulously analyzed data from 150 community-dwelling adults, ranging in age from 50 to 80 years. Its primary objective was to investigate the intricate relationships among physical function, systolic blood pressure, hearing sensitivity, and cognitive performance. The results yielded a clear and statistically significant association: participants exhibiting higher levels of physical function consistently presented with lower hearing thresholds, a clinical indicator of superior hearing sensitivity. Crucially, this robust association between physical prowess and auditory acuity remained independent of systolic blood pressure, a key cardiovascular health marker often implicated in age-related health declines. Despite the expected increase in blood pressure with advancing age within the study cohort, it did not emerge as a mediating factor in the observed relationship between physical function and hearing.
Challenging Conventional Wisdom: Unpacking the Links Between Healthy Aging and Hearing
For decades, the age-related deterioration across various physiological systems – including physical mobility, sensory perception (like hearing), and cognitive faculties – has frequently been attributed, at least in part, to shared underlying cardiovascular factors. Scientists and clinicians have traditionally posited that a decline in cardiovascular health acts as a common pathway, contributing to a cascade of functional impairments throughout the body as individuals age. The USC research team, therefore, designed their study to specifically test whether systolic blood pressure might serve as one such pathway connecting physical function with both hearing and cognitive outcomes. The results, however, painted a different and more nuanced picture.
Dr. Jean Neils-Strunjas, Ph.D., chair of the Department of Communication Sciences and Disorders at the University of South Carolina and the lead author of this seminal study, articulated the significance of these findings: “Aging has long been associated with decreases in physical, sensory, and cognitive functions, and scientists and clinicians previously assumed that cardiovascular health was the common underlying factor in these declines.” She continued, highlighting the study’s most striking revelation, “However, our research showed that systolic blood pressure — a measure of cardiovascular health that increases with age — did not appear to impact hearing loss, while physical function seemed to have a protective effect in the group we studied, which was comprised mostly of educated women.” This statement underscores a potential paradigm shift in understanding the etiology of presbycusis (age-related hearing loss) and suggests that interventions focused solely on cardiovascular risk factors might be insufficient in comprehensively addressing sensory aging.
Methodological Rigor: Data from the Aging Brain Cohort
The study leveraged invaluable data from the University of South Carolina’s ongoing Aging Brain Cohort, a comprehensive, long-term research initiative dedicated to collecting a wide array of behavioral, neuroimaging, genetic, and other health-related information pertinent to the aging process. Participants in the study underwent a battery of assessments designed to precisely measure their hearing capabilities, cognitive performance, blood pressure readings, and physical function levels.
Hearing sensitivity, a critical component of the study, was meticulously assessed using pure-tone audiometry. This gold-standard clinical procedure involved presenting tones at varying frequencies, from 250 Hz (low pitch) through 8,000 Hz (high pitch), to both ears, allowing researchers to determine the quietest sound an individual could hear at each frequency. This comprehensive range of frequencies is crucial because age-related hearing loss often manifests first in the higher frequencies. Cognitive performance was evaluated using the Montreal Cognitive Assessment (MoCA), a widely recognized screening tool for mild cognitive impairment. Physical function, on the other hand, was measured using the RAND 36-Item Health Survey, specifically its physical function subscale. This self-report questionnaire probes participants about the extent to which their health limits their engagement in various everyday activities, including basic mobility tasks like walking, climbing stairs, performing moderate or vigorous exercise, and completing personal-care routines. Higher scores on this subscale indicated fewer self-reported physical limitations, signifying better overall physical function.
Quantifying the Protective Effect: Better Physical Function and Enhanced Hearing
After carefully adjusting for confounding variables such as age and sex, the statistical analysis revealed a significant and positive association: individuals with higher physical-function scores consistently demonstrated better hearing thresholds. The researchers quantified this effect, estimating that for every 10-point increase in an individual’s physical-function score (as measured by the RAND 36-Item Health Survey), there corresponded an average 1.35 dB HL (decibel Hearing Level) improvement in hearing threshold.
While the magnitude of this effect might appear modest at first glance – the authors noted that a substantial 30-point difference in physical function would translate to approximately a 4 dB HL difference in hearing – its implications are far-reaching, particularly at the population level. Hearing loss is an exceedingly common condition among older adults globally. According to the World Health Organization (WHO), over 430 million people worldwide require rehabilitation for disabling hearing loss, and this number is projected to rise significantly, with a large proportion being older adults. In the United States, data from the National Institute on Deafness and Other Communication Disorders (NIDCD) indicates that approximately one in three people between the ages of 65 and 74 has hearing loss, and nearly half of those 75 and older have difficulty hearing. Even relatively small improvements in hearing sensitivity across a large population could collectively translate into substantial public health benefits, enhancing quality of life, reducing social isolation, and potentially mitigating cognitive decline associated with untreated hearing loss.
The study also reaffirmed established predictors of age-related health changes. Age, as expected, remained a potent predictor of both systolic blood pressure and hearing sensitivity. On average, every 10-year increment in age was associated with a 7.5 mm Hg increase in systolic blood pressure and a notable 8.78 dB HL increase in hearing threshold, underscoring the pervasive impact of chronological aging on these physiological parameters. Furthermore, male participants exhibited generally poorer hearing than their female counterparts, with average hearing thresholds approximately 4.9 dB HL higher, a finding consistent with other epidemiological studies on hearing loss prevalence.
In stark contrast to the strong link between physical function and hearing, systolic blood pressure did not show a significant association with either hearing thresholds or cognitive performance within the study population. Similarly, physical function demonstrated only a minimal association with cognition, and this relationship, too, was not mediated by blood pressure. These findings further solidify the idea that the protective effect of physical function on hearing operates through pathways distinct from, or at least not solely dependent on, traditional cardiovascular markers like systolic blood pressure.
Dr. Neils-Strunjas summarized these critical distinctions: “These findings suggest that systolic blood pressure does not appear to be a meaningful predictor of hearing loss or cognitive performance in healthy older adults.” She further elaborated on the broader implications, stating, “When taken together with the positive association between physical function and hearing, our research indicates that targeting physical activity directly — rather than relying solely on blood pressure management — could help preserve hearing and cognitive health. Aside from these findings, we recommend that anyone with high blood pressure consult their medical provider.” This emphasizes a shift towards a more holistic, activity-centric approach to healthy aging.
Unraveling the Mechanisms: Possible Pathways and Clinical Implications
It is crucial to acknowledge that this cross-sectional study, by design, captures participants at a single point in time. Consequently, while it identifies a robust association, it cannot definitively establish a direct cause-and-effect relationship. Researchers cannot conclude from this data alone whether superior physical function causes better hearing, whether a certain hearing status influences activity levels, or if other unmeasured underlying factors simultaneously affect both. Nevertheless, the authors have identified several plausible biological and physiological pathways through which physical activity and robust physical function could theoretically support and safeguard auditory health.
These potential mechanisms include:
- Improved Vascular Function and Blood Flow: Regular physical activity enhances endothelial function, leading to healthier blood vessels and improved microcirculation. The cochlea, the primary organ of hearing, is highly metabolically active and exquisitely sensitive to blood supply. Enhanced blood flow could better deliver oxygen and nutrients while efficiently removing metabolic waste products, thereby protecting delicate cochlear structures.
- Reduced Inflammation and Oxidative Stress: Chronic low-grade inflammation and oxidative stress are known contributors to cellular damage and aging across various tissues, including the inner ear. Physical activity is a powerful anti-inflammatory agent and can bolster the body’s antioxidant defenses, potentially mitigating damage to hair cells and auditory neurons.
- Better Metabolic Regulation: Physical activity improves glucose metabolism and insulin sensitivity, preventing metabolic dysfunction that can negatively impact microvascular health and energy production within the cochlea.
- Improved Mitochondrial Health: Mitochondria are the powerhouses of cells. Physical exercise is known to enhance mitochondrial biogenesis and function, providing the abundant energy required by the high metabolic demands of the auditory system.
- Protection Against Microvascular Damage within the Cochlea: The tiny blood vessels supplying the inner ear are particularly vulnerable to age-related damage. By improving overall cardiovascular health (even if systolic blood pressure isn’t the sole mediator), physical activity can directly protect these critical microvessels from atherosclerosis and other forms of deterioration.
For clinicians across various disciplines, these findings advocate for a more integrated and comprehensive approach to healthy aging. This approach would necessarily consider mobility and physical function as critical components alongside traditional assessments of hearing, cognition, and cardiovascular health. Incorporating assessments of physical limitations into routine clinical evaluations could serve as an early identifier for older adults who might be at a heightened risk of developing or experiencing progressive hearing impairment. Audiologists, geriatricians, primary care physicians, and physical therapists could collaborate more closely to develop holistic care plans that emphasize physical activity as a cornerstone of sensory preservation.
Important Study Limitations and Future Directions
The authors prudently highlighted several limitations inherent to the study, which necessitate cautious interpretation and underscore avenues for future research. Foremost among these is the demographic composition of the study sample. The cohort was predominantly female (74%), nearly exclusively White (99%), and highly educated, with a remarkable 84% of participants reporting at least a college-level education. Participants were also generally healthy, exhibiting average hearing and cognitive scores well within normal ranges. These characteristics mean that the findings, while significant, may not be universally applicable to the broader and more diverse older adult population, particularly those from different socioeconomic, ethnic, or health backgrounds.
Furthermore, the measurement of physical function relied on self-report via a questionnaire rather than objective, direct measurements such as gait speed, muscle strength assessments, or accelerometer-recorded activity levels. While self-report measures are valuable, they can be subject to recall bias or subjective interpretation. The relatively small sample size of 150 participants also limits the statistical power and generalizability of the findings. Finally, differences in participants’ use of blood-pressure medications, which could influence systolic blood pressure readings, posed an additional analytical complexity.
Despite these limitations, the ongoing nature of the Aging Brain Cohort offers a promising future. The research team is currently in the process of collecting five-year follow-up data from the participants. This longitudinal data will be invaluable for determining whether changes in physical function over an extended period are indeed accompanied by corresponding changes in hearing sensitivity, thereby moving closer to establishing a causal link. Future research should also prioritize replicating these findings in larger, more diverse cohorts, employing objective measures of physical activity, and exploring a broader spectrum of cardiovascular and metabolic health markers beyond just systolic blood pressure. Investigations into inflammatory markers, metabolic health panels, immune system function, and neurotrophic factor levels could provide a more comprehensive understanding of the complex interplay between physical health and sensory aging.
In conclusion, while additional research is undoubtedly warranted to solidify these findings and explore their full implications, this study from the University of South Carolina adds substantial weight to the growing body of evidence advocating for the profound benefits of maintaining mobility and an active lifestyle throughout the aging process. It suggests that physical activity is not merely beneficial for cardiovascular health, musculoskeletal integrity, or cognitive vitality, but may also serve as a crucial, independent protective factor for healthier sensory aging, including the invaluable preservation of hearing. These insights pave the way for novel public health initiatives and clinical recommendations aimed at empowering older adults to live richer, more connected lives by embracing an active approach to healthy aging.
Reference:
Neils-Strunjas J, Arjmandi M, Hajihosseini M, et al. Physical function impacts hearing without mediation from systolic blood pressure. Scientific Reports. 2026. https://doi.org/10.1038/s41598-026-55494-w
Source: Scientific Reports, University of South Carolina
