Carpal tunnel syndrome diagnosis as a risk factor for falls.

Purpose: Subclinical peroneal neuropathy without overt foot drop has been linked to increased fall risk in adults, yet remains under reported due to subtle symptoms and lack of awareness. Patients with carpal tunnel syndrome (CTS) often experience other nerve entrapments, prompting this study to evaluate CTS (a proxy for peroneal nerve entrapment) as a significant predictor of time to first fall.

Methods: Data from the Merative MarketScan Research Databases (2007-2021) were used to identify adult patients using ICD-9/10 codes. Patients were stratified by CTS diagnosis and fall occurrences, with relevant comorbidities recorded. A survival analysis employing the Cox proportional hazards model assessed relationships between CTS, comorbidities, and future fall risk, accounting for changes in health status over time. Age was the time scale with CTS as a time-varying predictor. This approach isolated CTS-associated risk, while considering the natural increase in fall risk with age.

Results: Among 63,187,681 subjects (mean age = 52.82 years ± 7.61), 1,411,695 had a diagnosis of CTS. Of those with CTS, 45,479 patients had a future fall. Univariate analysis showed significant associations between CTS and higher rates of arthritis and diabetes, while heart disease was less prevalent. CTS increased fall risk by 25% (HR 1.25, p < .005). Heart disease was associated with a 10% increase in fall risk (HR 1.10, p < .005), while arthritis and diabetes increased fall risk by 2% (both HR 1.02, p < .005). Kaplan-Meier curve illustrated a steeper decline in survival probability for the CTS group, indicating they experienced falls at younger ages and at a higher rate than those without CTS (χ² = 4386.4, p < .001).

Conclusion: Prior diagnosis of CTS is associated with an increased fall risk. Providers should screen CTS patients for fall risk and implement appropriate monitoring strategies. Further investigation on the role of peroneal nerve entrapment in this increased fall risk is warranted. This study identifies a treatable cause of falls, with potential to enhance patient safety and reduce fall-related morbidity.