People with insomnia are at increased risk of atrial fibrillation (AF), according to a large retrospective study.
In a real-world cohort of 1,780,764 individuals (median age 63 years, 45.5 percent male, 12.2 percent had a history of insomnia) who were free of cardiovascular disease at baseline, the incidence rate of AF over a median follow‐up period of 3.7 years was 57.8 per 10,000 person‐years among those with a history of insomnia vs 35.4 per 10,000 person‐years among those without insomnia (p<0.001). [J Am Heart Assoc 2026;doi:10.1161/JAHA.125.045149]
Insomnia was associated with a 14-percent increase in the risk of AF (hazard ratio [HR], 1.14, 95 percent confidence interval [CI], 1.10–1.18), independent of sleep apnoea and other traditional risk factors for AF.
“The addition of insomnia to traditional AF risk factors showed a possibility of further improvement in the prediction for future AF development,” the investigators noted.
In subgroup analyses, the association between insomnia and incident AF was stronger in younger individuals (<65 years) and women compared with older adults (≥65 years) and men. This finding, according to the investigators, suggests an important role for insomnia in the development of AF, even in populations generally considered to have fewer conventional risk factors for AF.
The science linking insomnia to AF is far from settled, but the investigators proposed possible mechanisms.
“Insomnia can lead to hypothalamic–pituitary–adrenal axis dysregulation, increased systemic inflammation, and enhanced sympathetic activity, resulting in elevated cortisol and catecholamine levels. These changes may cause elevated blood pressure, heart rate variability, and atherosclerosis, which are the risk factors for CVD … [and] are also thought to contribute to the development of AF,” they explained.
“Additionally, even a single night of sleep loss has been shown to increase the risk of atrial electromechanical delay in healthy young adults. These suggest insufficient sleep itself could be a potential risk factor for AF with a possible common pathogenesis among insomnia, sleep apnoea syndrome, and alcohol intake–related poor sleep quality,” they continued.
Overall, the study underscores the importance of increased awareness of insomnia as an important and independent risk factor for AF, especially in individuals at low risk of AF, given the prevalence of insomnia in the general population and the substantial impact of AF on quality of life, according to the investigators.
However, the investigators acknowledged that active assessment of insomnia may be resource-consuming in routine practice. A more realistic approach is to use sleep-related questionnaires during clinic visits, they said. On the other hand, wearable devices such as smartwatches offer a promising means of quantifying and visualizing sleep duration and quality.
The study was based on the DeSC database, which is a nationwide, real‐world cohort representative of the general population in Japan. Future prospective studies are needed to more accurately assess the relationship between insomnia and incident AF, the investigators said.