Co-morbid Insomnia and Sleep Apnea Is Associated with Uncontrolled Hypertension in a Middle-aged Population.

Abstract

Introduction: Co-morbid insomnia and sleep apnea (COMISA) has been linked to poorer health outcomes and increased all-cause mortality compared with either insomnia or obstructive sleep apnea (OSA) alone.

Materials and methods: We investigated the relationship between COMISA and uncontrolled hypertension in the Swedish CardioPulmonary BioImage Study (SCAPIS). A cross-sectional analysis including participants from the SCAPIS Gothenburg cohort (n=3832, 46% males, age 57.5±4.3 years, body mass index 26.6±4.3 kg/m2) was performed. Subjects underwent a comprehensive examination, including functional tests and a home polygraph sleep recording. COMISA was defined as an apnea-hypopnea index (AHI) >10 events/h and an Insomnia Severity Index score ≥15. Blood pressure (BP) status was characterized as uncontrolled hypertension (office systolic BP ≥140 mmHg or diastolic BP ≥90 mmHg), controlled hypertension (antihypertensive medication-treated hypertension with systolic/diastolic BP < 140/90 mmHg) or normotension with systolic/diastolic BP <140/90 mmHg.

Results: The prevalence of COMISA was 3.1% in the population and 14.5% among OSA patients (AHI >10 events/h). AHI was comparable between OSA-only and COMISA patients (18±9 vs. 19±9 events/h, P=0.86). Uncontrolled hypertension was found in 4.4%, 4.5%, 7.9% and 10.2% of the control group, insomnia-only, OSA-only, and COMISA group, respectively (p<0.001). Compared to the control group, the risk of uncontrolled hypertension was significantly increased in the OSA-only group (odds ratio[95%CI]: OR 1.31[1.05 - 1.64], p=0.02) and the COMISA group (OR 1.88[1.23 - 2.89, p=0.004) after controlling for anthropometrics, lifestyle, comorbidities, Epworth sleepiness scale and nocturnal hypoxic exposure (T90, % recording time with oxygen saturation ≤ 90%). T90 was found to be a significant mediator in the relationship between both OSA and COMISA to uncontrolled hypertension.

Conclusions: This study is the first to demonstrate an independent association between COMISA and uncontrolled hypertension in the general population. These findings provide novel insights for identifying subgroups of OSA patients at risk of adverse cardiovascular consequences. Furthermore, our results underscore the importance of recognizing sleep health as a multidimensional construct and advocate for personalized treatment strategies to effectively combat the burden of this common sleep disorder. (See data supplement for graphical abstract and summary of key findings).