Protecting Sleep, Promoting Health in Later Life: A Randomized Clinical Trial
What this study found
SLEEP did not improve sleep continuity or depth and reduced total sleep time by about 30 minutes per night over 18 months. Compared with NUTRITION, SLEEP was associated with a decline in physical health-related quality of life and an increase in medical burden (cardiovascular illness); inflammation markers, BMI, and exercise did not explain these changes. Authors conclude that in healthy adults aged ≥75 without sleep complaints, modest time-in-bed restriction may be detrimental; allowing about 7.5 hours of sleep nightly was associated with better maintenance of physical health-related…
- Study & population
- Single-blind, randomized clinical trial conducted at a university-based sleep center; 64 healthy elderly adults aged ≥75 years (mean age 79; 34 men, 30 women) without sleep/wake complaints or psychiatric or sleep disorder; eligible with Hamilton Depression Rating Scale ≤7 and Mini-Mental State Examination ≥24; randomly assigned to SLEEP or NUTRITION for 18…
- Key limitation
- Absence of a noninterventional control group limits causal interpretation of nutrition versus sleep restriction effects; lipid profiles were not measured; CIRS-G data were not collected at 30 months; CPAP use in a subset of participants; results unchanged when excluding those participants; participants were healthy…
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Open PDFOriginal abstract
Objectives: To determine in healthy people aged ≥75 years 1) if restricting time in bed and education in health sleep practices are superior to an attention-only control condition (i.e., education in healthy dietary practices) for maintaining or enhancing sleep continuity and depth over 2.5 years; and 2) if maintenance or enhancement of sleep continuity and depth promotes the maintenance or enhancement of health-related quality of life. Methods: Single-blind, randomized, clinical trial in a university-based sleep center, enrolling 64 adults (n = 30 women, 34 men; mean age = 79 years) without sleep/wake complaints (e.g., insomnia or daytime sleepiness), followed by randomized assignment to either: 1) restriction of time in bed by delaying bedtime 30 minutes nightly for 18 months, together with education in healthy sleep practices (SLEEP); or 2) attention-only control condition with education in health dietary practices (NUTRITION). Results: SLEEP did not enhance sleep continuity or depth; however, compared with NUTRITION, SLEEP was associated with decreased time spent asleep (about 30 minutes nightly over 18 months). Contrary to hypothesis, participants in SLEEP reported a decrement in physical health-related quality of life and an increase in medical burden (cardiovascular illness), relative to NUTRITION. Neither markers of inflammation, body mass index, or exercise explained treatment-related changes in medical burden. Conclusions: Although we cannot exclude a positive effect of education in healthy nutrition, for healthy elderly >75 years of age without sleep complaints, reducing sleep time may be detrimental, whereas allowing more time to sleep (about 7.5 hours nightly) is associated with better maintenance of physical health-related quality of life and stability of medical illness burden over 30 months. IL-6 = interleukin-6; TNF-&agr; = tumor necrosis factor-&agr;.