Evaluation of the Relationship Between Fall Risk, Muscle Strength, and Anticholinergic Burden in Geriatric Patients Presenting to the Emergency Department

Overview

Falls are common among older adults and can lead to serious injury. This study looks at whether taking many medications (polypharmacy), the anticholinergic burden of those medications (a measure of side effects that can affect memory, balance, and muscle function), and sarcopenia (age-related loss of muscle mass and strength) are related to fall risk in older adults visiting the emergency department. Patients aged 65 and older who come to the emergency department will be invited to take part. With their consent, researchers will review the medications they are taking and calculate an anticholinergic burden score. Researchers will also measure the patients' hand grip strength and use ultrasound to measure the thickness of the quadriceps muscle in the thigh, both of which are used to assess muscle health. Information about the patients' history of falls in the past year, hospital stays, and other health conditions will also be collected. All measurements are non-invasive, are already used in routine clinical practice, and are performed only once during the emergency department visit. No experimental treatment or medication will be given as part of this study. The goal of this study is to understand how polypharmacy, anticholinergic burden, and sarcopenia relate to fall risk, both individually and together, so that older adults at higher risk of falling can be identified earlier and offered appropriate prevention strategies.

Falls are a leading cause of morbidity, injury, and increased health care utilization among older adults presenting to the emergency department. Polypharmacy, high anticholinergic medication burden, and sarcopenia have each been independently associated with increased fall risk in older populations, but their combined and possibly synergistic effect in the acute emergency department setting has not been well characterized. This is a single-center, prospective, cross-sectional observational study conducted at the Department of Emergency Medicine, Gazi University Faculty of Medicine. Patients aged 65 years or older presenting to the emergency department will be screened for eligibility. After initial evaluation by the treating physician, eligible patients will be informed about the study by a member of the research team, and those who provide written informed consent will be enrolled. Exclusion criteria include: prior major upper or lower extremity surgery, prosthesis, or amputation that would prevent ultrasound or hand-grip measurement; acute bilateral femur or hip fracture; neuromuscular disease (e.g., ALS, myopathy); terminal or palliative status with limited ability to cooperate with measurements; severe delirium or inability to cooperate with hand-grip testing; ECOG Performance Status of 3 or 4; and bedbound status or stroke sequelae preventing assessment. Data collection. Using a study-specific case report form, the following will be recorded at the time of the emergency department visit: age, sex, number of comorbidities, fall history over the preceding 12 months, and prior hospitalization history. All medications currently used by the patient - prescription, over-the-counter, and herbal - will be documented. Concurrent use of 5 or more medications will be classified as polypharmacy, and 10 or more as excessive polypharmacy. Anticholinergic burden will be calculated using the Anticholinergic Burden Scale (ACB), with a total score of 3 or higher defined as high anticholinergic burden. Functional status and frailty will be assessed using the Clinical Frailty Scale (CFS) and the ECOG Performance Status scale. Muscle assessment. Hand grip strength will be measured using a hand dynamometer, and patients will be classified as probable sarcopenia (+) or probable sarcopenia (-) based on this measurement. Quadriceps muscle thickness will be assessed by point-of-care ultrasound (GE Healthcare Venue Point of Care) using a linear probe, with the patient in the supine position. Measurements will be taken at the midpoint between the anterior superior iliac spine and the patella, on the anterior thigh. Rectus femoris (RF) and vastus intermedius (VI) thickness will be measured separately, and combined muscle thickness (CMT) - the distance between the subcutaneous fat layer and the femoral cortex - will be recorded in millimeters. Sarcopenia will be defined according to EWGSOP2 criteria. Ultrasound measurements will be performed by two emergency medicine residents with prior basic ultrasound training, following a standardized 4-hour theoretical and hands-on training session delivered by an emergency medicine faculty member with 8 years of point-of-care ultrasound experience. A pilot phase involving 20 patients per trained resident will be used to confirm image quality and measurement adequacy before full enrollment begins. All ultrasound images will be stored and reviewed by emergency medicine faculty; measurements with inadequate image quality will be excluded from analysis, though other adequate-quality extremity data from the same patient will still be included. Outcomes. The relationship between polypharmacy, anticholinergic burden, and sarcopenia parameters (muscle thickness and grip strength) and fall risk and clinical outcomes (major injury, hospital admission, emergency department length of stay, need for consultation) will be evaluated using multivariable statistical methods. No study-specific interventions, treatments, or additional laboratory tests will be performed; all assessments are one-time and use measurements already standard in routine clinical care. Findings will be reported in accordance with the STROBE guidelines for observational studies. Based on a reported 12-month fall incidence of 37.2% among older adults in Turkey and expected annual enrollment volumes, a minimum sample size of 313 patients (157 male, 156 female) was calculated for this study.