The causal role of insomnia in multiple chronic diseases: a systematic review and meta-analysis of Mendelian randomization studies

Abstract Background: Insomnia is a significant public health issue interconnected with multiple chronic diseases, though the causal association remains elusive. Thus, the objective of this investigation is to undertake a meta-analysis of relevant Mendelian randomization research endeavors to validate the causal connection between insomnia and a spectrum of persistent afflictions. Methods: The study searched databases for Mendelian randomization(MR) studies exploring the causal relationship between insomnia and chronic diseases, extracted data, and performed quality assessment. A meta-analysis was performed based on all MR studies that met the criteria and on the results of a de novo analysis based on data from the FinnGen consortium. Results: Genetically predicted insomnia was associated with an increased risk of type 2 diabetes mellitus, 13 circulatory disease, 7 neuropsychological diseases, 3 digestive diseases, 10 pain diseases, asthma, and osteoarthritis as well as cancers of the respiratory system. In contrast, genetically predicted insomnia was not associated with 4 circulatory diseases, 8 neuropsychological diseases, 4 digestive diseases, tuberculosis, and 2 skeletal musculature diseases. Conclusions: Insomnia has a causal association with numerous chronic diseases. Timely identification and management of insomnia are essential to prevent secondary illnesses, improve quality of life, and optimize healthcare resource utilization.