Muscle fatigability, sleep disturbance and fall risk in older adults: A cross-sectional study

Abstract Background Sleep disturbance and fatigue may increase the risk of falls in older adults. This study examined the individual and combined associations of subjective fatigue, objective measured muscle fatigability, physical performance and sleep disturbance with fall risk in residential care settings. Methods This study included 217 residents and assessed objective muscle fatigability and recovery using repeated handgrip strength measurements, subjective fatigue (Multidimensional Fatigue Inventory, MFI), insomnia (Athens Insomnia Scale, AIS), sleep apnoea risk (STOP-BANG) and physical performance (Short Physical Performance Battery, SPPB). Falls were documented retrospectively (12 months) and prospectively (4 months). Subgroup analyses examined combinations of these factors. Results Of 217 participants, 39.6% (n = 86) were classified as fallers, based on their 12 months fall history. Fallers were older and predominantly female. During the 4-month follow-up, 67.4% of fallers experienced a fall compared to 2.3% of non-fallers. Both objective muscle fatigability and SPPB independently increased the risk of falling (AOR=3.45 and AOR=2.75). These risks were further increased when combined with sleep disorders, showing higher associations (AOR=3.34-5.05 for muscle fatigability and AOR=3.57-4.41 for SPBB). Poor muscle recovery with sleep disorders showed the strongest associations (AOR=5.12-5.21), while MFI showed no significant associations. Conclusions The results highlight a complex interaction between muscle fatigability, sleep disturbance and physical performance in increasing the risk of falls in older adults in residential care. Objective measures of muscle fatigability and recovery proved to be better predictors of falls than subjective assessments. Targeted prevention strategies should therefore address both fatigue/recovery capacity and sleep quality. Key messages • In residential care, muscle fatigability, recovery and physical performance measures are associated with fall risk, especially when combined with sleep disorders. • Fall prevention in residential care settings must consider both physical condition and sleep health.