Insomnia is associated with higher rates of cardiovascular outcomes and death in patients with hypertension: a propensity score matching study

Background Chronic insomnia is a common condition associated with impaired quality of life. Recent evidence from population studies suggests that insomnia may be associated with increased prevalence and incidence of hypertension. However, it is unclear whether insomnia modulates the risk of CV events in patients with hypertension regardless of traditional risk factors. Purpose To evaluate the impact of insomnia on cardiovascular and mortality endpoints in patients with hypertension. Methods We performed a retrospective cohort analysis using the TriNetX Global Health Research Network, based on anonymized electronic health records. We identified all adult patients (>40 years) with a history of hypertension without a diagnosis of insomnia. For mitigating potential underreporting of insomnia in the control group, we excluded patients using several hypnotic classes. Patients with prior myocardial infarction (MI), previous stroke, and heart failure (HF) were excluded from both groups. Patients with co-morbid insomnia and hypertension were matched to the reference cohort (hypertension-only) using propensity score matching in a 1:1 ratio for age, sex, ethnicity, body mass index, diabetes, dyslipidemia, smoking, sleep apnea, and chronic kidney disease. Primary outcome: composite of death, MI, and stroke. Secondary outcomes included individual components of the primary outcome and HF. Results After propensity score matching, 1,203,206 patients were included in the analysis (50% in each group): mean age 65±10 years, 59.3% females. Over a median follow-up of 2.9 years, patients with co-morbid insomnia and hypertension had a 76% higher chance of combined CV events (HR: 1.76, 95% CI: 1.74 – 1.79) than those with hypertension-only. The figure shows the survival probability of the primary outcome in the two groups. Consistent results were observed for males (HR: 1.82, 95% CI: 1.78 – 1.85) and female sex at birth (HR: 1.73, 95% CI: 1.70 – 1.76). Analyses of the individual components of the primary outcome and HF revealed consistent results: mortality (HR: 1.52, 95% CI: 1.50 – 1.56); MI (HR: 2.74, 95% CI: 2.67 – 2.82), stroke (HR: 1.79, 95% CI: 1.76 – 1.83), and HF (HR: 1.99, 95% CI: 1.96 – 2.02). Conclusion In patients with hypertension, the presence of insomnia was associated with a higher rate of the occurrence of CV events and death. Prospective investigations are needed to fully understand the impact of insomnia on patients with hypertension.