Older adults with heart failure who had inefficient sleep had significantly higher NT-proBNP levels, and sleep irregularity was linked to HF symptom load, frailty, functional performance, and quality of life.
Key Findings
Results
42% of older adults with heart failure had inefficient sleep based on average sleep efficiency below 80% as measured by actigraphy.
150 older adults aged ≥65 years with a diagnosis of HF were enrolled; accelerometry data from 145 participants were analysed.
Sleep efficiency was the primary outcome measure, calculated from a 7-day wrist accelerometer wear period.
Valid nights required minimum 3 nights of recording, noon-to-noon with ≥16 hours wear-time.
Study was conducted at an outpatient HF clinic within a tertiary cardiology service in a National Health Service hospital in the UK between March and October 2023.
Results
Patients with inefficient sleep (efficiency <80%) had significantly higher plasma NT-proBNP levels compared to those with sleep efficiency ≥80%.
The difference in NT-proBNP levels between groups was statistically significant (p=0.044).
NT-proBNP is a cardiac biomarker reflecting cardiac stress and heart failure severity.
No statistically significant difference was noted in 4MWT, HGST, TUGT, Barthel Index, KCCQ-12, or Clinical Frailty Scale between the two sleep efficiency groups.
Results
Lower sleep efficiency was independently associated with greater functional dependence and worse frailty in older adults with heart failure.
Lower sleep efficiency was associated with lower Barthel Index scores (adjusted β=0.271, p=0.016).
Lower sleep efficiency was associated with worse frailty as measured by the Clinical Frailty Scale (adjusted β=-0.017, p=0.014).
Regression analyses were adjusted for age, gender, and comorbidities.
Results
Lower Sleep Regularity Index (SRI) was associated with worse New York Heart Association class, greater functional dependence, worse frailty, and poorer quality of life.
Lower SRI was associated with worse NYHA class (adjusted β=-0.009, p=0.007).
Lower SRI was associated with lower Barthel Index scores (adjusted β=0.310, p<0.001).
Lower SRI was associated with worse frailty (adjusted β=-0.017, p<0.001).
Lower SRI was associated with worse quality of life as measured by KCCQ-12 (adjusted β=0.344, p=0.001).
Results
Longer wake after sleep onset (WASO) was associated with slower gait speed in older adults with heart failure.
Longer WASO was associated with slower gait speed on the 4-metre walk test (adjusted β=-0.039, p=0.040).
WASO is a measure of sleep fragmentation reflecting time spent awake after initially falling asleep.
This association was adjusted for age, gender, and comorbidities.
Methods
Wrist actigraphy was used to assess multiple sleep parameters over 7 days in an outpatient heart failure population of older adults.
Sleep parameters studied included average sleep efficiency, sleep period time window, sleep duration, sleep onset and wake-up time, WASO, sleep interruptions, and Sleep Regularity Index.
Participants wore a wrist-accelerometer for 7 days; device started recording on Day 1 after clinical assessments on Day 0.
Clinical assessments on Day 0 included 4MWT, HGST, TUGT, Barthel Index, KCCQ-12, and Clinical Frailty Scale.
The study design was cross-sectional.
What This Means
This research suggests that poor sleep is highly prevalent among older heart failure patients, with 42% of the 145 participants studied showing inefficient sleep as measured by a wrist-worn activity tracker worn over 7 days. Patients who slept inefficiently had higher blood levels of NT-proBNP, a marker that reflects how hard the heart is working and how severe heart failure may be. This study also found that poor sleep efficiency was linked to greater difficulty performing daily activities and higher levels of frailty, even after accounting for age, sex, and other health conditions.
Beyond just sleep efficiency, the regularity of sleep patterns also mattered. Patients with more irregular sleep schedules — those who went to bed and woke up at inconsistent times — tended to have worse heart failure symptoms, greater frailty, more dependence on others for daily tasks, and lower quality of life. Additionally, patients who woke up more frequently during the night walked more slowly on a standardized gait test, suggesting a connection between disrupted sleep and physical performance.
This research suggests that sleep quality and consistency are meaningfully connected to the overall health status of older adults living with heart failure. Wrist actigraphy appears to be a feasible tool for capturing these sleep patterns in an outpatient clinical setting. The findings highlight sleep as a potentially important area to monitor and address in the care of older heart failure patients, given its associations with cardiac stress markers, functional ability, frailty, and quality of life.
Krishnan S, Taylor S, Edwardson C, Rowlands A, Squire I, Sze S. (2026). Device-assessed sleep health among older patients with heart failure: a cross-sectional study using actigraphy.. BMJ open. https://doi.org/10.1136/bmjopen-2025-111622