Parkinson’s disease (PD) is an age-related neurological disorder characterized by bradykinesia, tremor, and postural instability. Early weight loss following diagnosis is linked to a poorer prognosis. In older adults, loss of skeletal muscle increases the risk of falls and related injuries, making body composition measurements, such as muscle and fat mass, critical in PD, where the risk of falls is high. Traditional body composition analysis equipment is bulky, expensive, and primarily limited to research settings(1). This study evaluated the reliability of the portable SECA mBCA 525 device, which has not been validated in PD populations.

Nineteen participants with PD and 11 household controls were recruited from Movement Disorder Clinics. Participants underwent body composition analysis using the SECA mBCA 525 device. A mild electrical current is passed between adhesive electrodes applied to hands and feet, and the impedance is measured. Proprietary algorithms use the impedance data and manually entered data, such as age, weight, height, waist circumference and reported activity level, to estimate the fat, lean, and water mass (in kilograms). Measurements were repeated at two visits one month apart to assess test-retest reliability.

Data were collected from 30 participants: 19 with PD and 11 controls. Five PD participants experienced data collection failures, all exhibiting rest tremor. However, tremor amplitude was similar to the group average (mean 1.6, standard deviation 1.9 vs. mean 1.6, standard deviation 1.2).

Two sets of complete data were collected for 14 participants with PD and 10 controls. No significant differences in lean- or fat mass estimates were observed between trials 1 and 2 (Bland-Altman plot and linear regression, p>0.05).

The SECA mBCA 525 portable bio-impedance analysis device demonstrated good test-retest reliability for assessing lean and fat mass in individuals with and without PD. However, data collection failures, potentially caused by limb tremor, limit its applicability in PD studies.