Highlight
- This randomized controlled trial compared a sleep optimization intervention (Sleep-Opt) with a healthy living control in adults with type 1 diabetes (T1D) who had short or irregular sleep.
- Sleep quality improved and diabetes distress decreased shortly after intervention in the Sleep-Opt group, but glycemic targets (A1C and CGM metrics) did not significantly differ overall between groups.
- A subgroup with suboptimal baseline glycemic control (A1C ≥7%) showed statistically significant improvement in A1C after Sleep-Opt intervention.
- Both interventions improved sleep duration transiently, suggesting benefits of structured remote support irrespective of intervention focus.
Study Background
Type 1 diabetes (T1D) demands meticulous glycemic control to prevent microvascular and macrovascular complications. Despite advances in insulin therapy and glucose monitoring, many adults with T1D struggle to achieve glycemic targets, often influenced by behavioral and lifestyle factors. Sleep disturbances, including short duration and high variability, are common in T1D and may negatively impact glycemic control through alterations in insulin sensitivity, stress hormones, and behavior. However, interventional evidence evaluating whether improving sleep can directly enhance glycemic outcomes remains limited. This study addressed the unmet need by assessing the effect of a sleep-focused behavioral intervention on glycemic and psychological outcomes in adults with T1D and suboptimal sleep patterns.
Study Design
This parallel-group randomized controlled trial enrolled 144 adults with T1D characterized by either short sleep duration (<6.5 hours per night) or irregular sleep (≥1 hour variability in sleep duration). Participants were randomly assigned to either the Sleep-Opt intervention (n=73), a structured remote sleep behavioral program, or a Healthy Living attention control (n=71), both delivered remotely over eight sessions across 12 weeks.
Primary outcomes were measured at baseline and at 6, 12, and 24 weeks, with 12 weeks considered the primary endpoint. They included objective sleep measures (duration, regularity), glycated hemoglobin (A1C), and continuous glucose monitoring (CGM) parameters to assess glycemic control. Secondary outcomes comprised psychological measures such as diabetes distress and subjective sleep quality.
Key Findings
At the primary 12-week endpoint, there were no significant differences between the Sleep-Opt and Healthy Living groups in overall glycemic outcomes, including A1C and CGM metrics. Both groups experienced increased sleep duration at 6 weeks, but changes were not statistically different between groups, and no sustained sleep duration differences were observed at subsequent time points.
Notably, the Sleep-Opt group exhibited a significant short-term reduction in diabetes distress (median difference -0.18 with 95% CI -0.35 to -0.01) and an improvement in subjective sleep quality (median difference -0.96 with 95% CI -1.17 to -0.23) compared with the control at 6 weeks. These psychological benefits, however, were not sustained at 12 or 24 weeks.
A pre-specified interaction analysis indicated that baseline glycemic status modified the intervention effect. Specifically, participants with a baseline A1C ≥7% in the Sleep-Opt group had a statistically significant mean reduction in A1C of 0.32% (95% CI -0.64% to -0.005%) compared with the control group at 12 weeks (P = 0.047). This translates to a decrease of approximately 3.5 mmol/mol, which may be clinically meaningful in this subgroup. CGM parameters and sleep outcomes in this subgroup also reflected trends consistent with improved glycemic control.
Expert Commentary
This study provides valuable evidence clarifying the potential role of sleep interventions in T1D management. The improvements in diabetes distress and subjective sleep quality underscore the psychological benefits of targeted behavioral sleep interventions. However, the lack of a robust effect on glycemic outcomes in the overall population suggests that sleep optimization alone may not suffice to improve glucose control universally.
The differential response in those with suboptimal baseline glycemic control (A1C ≥7%) supports biologic plausibility that patients with more room for improvement may derive clinical benefit from behavioral modifications targeting sleep. The modest A1C reduction in this subgroup, while moderate, could reduce risk of long-term diabetes complications if sustained.
Limitations include reliance on remote intervention delivery which may affect engagement and adherence, and the relatively short follow-up period limiting assessment of durability of effects. The study did not incorporate mechanistic biomarkers such as insulin sensitivity or hormonal measures that might elucidate pathways mediating the sleep-glycemia link.
Our findings align with current guidelines emphasizing holistic diabetes care incorporating behavioral interventions, but reinforce that sleep improvement must be integrated with comprehensive glycemic management strategies.
Conclusion
Sleep-Opt behavioral intervention resulted in short-term improvements in psychological outcomes and subjective sleep quality in adults with T1D and poor or irregular sleep. Although no overall glycemic improvement was noted, a clinically relevant A1C reduction was observed in those with baseline A1C ≥7%, highlighting the potential selective utility of sleep optimization in this subgroup. Further longer-term, mechanistic studies are warranted to clarify how sleep-focused therapies can be optimally integrated into diabetes care paradigms to enhance glycemic outcomes.
Funding and ClinicalTrials.gov
The study was supported by institutional grants and funding agencies as detailed in the original publication. It was registered at ClinicalTrials.gov (identifier not provided in the abstract).
References
1. Martyn-Nemeth P, Duffecy J, Steffen AD, et al. Sleep Optimization to Improve Glycemic Targets in Adults With Type 1 Diabetes: A Randomized Controlled Parallel Intervention Trial. Diabetes Care. 2026;49(7):1270-1279. PMID: 42149583.
2. Reutrakul S, Van Cauter E. Sleep influences on obesity, insulin resistance, and risk of type 2 diabetes. Metabolism. 2018;84:56-66.
3. Knutson KL, Spiegel K, Penev P, Van Cauter E. The metabolic consequences of sleep deprivation. Sleep Med Rev. 2007;11(3):163-178.
4. Chasens ER, Sereika SM, Burke LE, Strollo PJ Jr. Excessive daytime sleepiness and obesity: the modified Epworth sleepiness scale for blacks. J Clin Sleep Med. 2014;10(6):673-679.
5. American Diabetes Association. 6. Glycemic Targets: Standards of Medical Care in Diabetes—2024. Diabetes Care. 2024;47(Suppl 1):S55-S64.