The Relationship Between Sleep Disorders and Insulin Resistance in Patients with Type 2 Diabetes: A Meta-Analysis

Abstract

Type 2 diabetes mellitus (T2DM) represents a rapidly growing global health challenge, significantly contributing to morbidity and mortality. While lifestyle and environmental factors are well-established in its etiology, emerging evidence increasingly highlights the central role of sleep health—encompassing duration, quality, regularity, and disorders—in metabolic dysfunction and disease progression. This study conducts a meta-analysis to clarify the relationship between sleep disturbances and insulin resistance/glycaemic control in individuals with T2DM. It synthesises evidence from epidemiological and experimental research showing that sleep abnormalities—including short or long duration, poor sleep quality, insomnia symptoms, disrupted circadian rhythms, and obstructive sleep apnoea (OSA)—are frequently present in people with T2DM and are associated with poorer glycaemic outcomes (e.g., elevated HbA₁c) and increased insulin resistance. Mechanistically, sleep disruption triggers sympathetic activation, hypothalamic–pituitary–adrenal-axis stimulation, inflammatory cytokine release, hormonal dysregulation of appetite/energy metabolism, and misalignment of circadian rhythms. Therapeutic interventions, particularly for OSA (e.g., CPAP), offer modest yet promising improvements in insulin sensitivity. Although methodological heterogeneity limits the precision of pooled estimates, the evidence supports a substantive role for sleep disturbances as independent contributors to metabolic dysregulation in T2DM. Therefore, integrating sleep assessment and management into diabetes care warrants serious consideration as a means to optimise metabolic outcomes.