Insomnia as a transdiagnostic factor across chronic illnesses common to primary care: a narrative review

Abstract

Background and Objective: Insomnia is one of the most common behavioral sleep disorders amongst adults with medical conditions, yet it is overlooked and under-treated in primary care settings. High cooccurrence rates of chronic illness and insomnia indicate sleep disorders may be a transdiagnostic factor underlying many comorbid illnesses. Little is known about the specific mechanisms that link insomnia and chronic illness. A better understanding of these mechanisms can augment current psychosocial treatments for chronic illness and have significant public health impact by being cost-efficient and time-saving as a transdiagnostic treatment. The purpose of this review is to propose a novel empirically-based theoretical model of insomnia as a transdiagnostic factor across chronic illnesses commonly seen in primary care (i.e., cardiovascular disease, diabetes, obesity, and chronic pain); to describe the shared psychological and behavioral mechanisms; and, to propose psychological and behavioral clinical recommendations for primary care. Methods: A search for key words was conducted in Google Scholar, PsycINFO, Science Direct, and PubMed to identify all articles prior to January 10th 2024 in the English language studying direct and indirect links between insomnia and adult chronic illness. Each article was reviewed and categorized based on the specific pathway represented and summarized in table formats. Findings from these tabulated summaries were extracted to identify mechanistic pathways and develop the theoretical model. Key Content and Findings: Studies support psychological and behavioral mechanisms that maintain the relationship between insomnia and chronic illness. Psychological mechanisms included cognitive and emotional factors (worry, rumination, depression, anxiety, emotion regulation) and cognitive functions (attention, memory). Behavioral mechanisms include treatment adherence and other lifestyle-related health behaviors. Clinical recommendations include incorporating routine screeners and assessments, training providers in cognitive behavioral therapy for insomnia (CBT-I), and including psychologists to address mental health and behavioral needs. Conclusions: Primary care providers should assess and treat insomnia within the context of chronic medical illness. Future research should focus on testing proposed mechanisms and develop interventions to include behavioral treatments for insomnia in primary care to prevent and manage chronic illness.