JMIR Publications

ABSTRACT

Background:

Recently, the phase angle (PhA) emerged as an essential indicator of cellular health. Most studies examined its association with physiological conditions, such as sarcopenia, frailty, and physical function in older populations. However, few studies explored the relationship between PhA, especially segmental PhA, and the psychological aspects of health, particularly cognitive function.

Objective:

We thus investigated the association between whole-body and segmental PhA and cognitive function in older adults.

Methods:

ndividuals aged 65+ years were recruited from adult community groups residing in Busan, South Korea, through the 2022 BUs-based Screening and Assessment Network study (BUSAN study) of Pusan National University Hospital. Participants’ whole-body and segmental PhAs were measured using a bioelectrical impedance analyzer (BWA 2.0 Body Water Analyzer, InBody, California, USA), and cognitive functions (overall and subdomains, including memory, orientation, attention, calculation, and language) were self-reported using the Korean version of the Mini-Mental State Examination (K-MMSE). Multiple linear regression analyses were performed to examine these associations.

Results:

This study included 625 older adults aged 65–96 years (444 women, 71.0%). A positive association was observed between whole-body PhA scores and cognitive function. We observed significant positive associations between the PhA of the whole body and lower limbs and cognitive function. Analysis of MMSE subdomains revealed that whole-body PhA was significantly related to memory, PhA of the upper limbs to orientation, and PhA of the lower limbs to orientation, attention, calculation, memory, and language functions. However, trunk PhA showed no significant association.

Conclusions:

We found a significant positive correlation between whole-body PhA and cognitive function in our sample, with nuanced relationships observed across different segmental PhA and cognitive subdomains. Therefore, this study revealed that PhA could be a useful tool for screening or preventing cognitive decline in the general older population, offering substantial evidence for future interventional studies. Further long-term investigation on these associations is warranted.