Sleep Quality as a Predictor of Coronary Artery Disease Severity in Geriatric Acute Coronary Syndrome

<i>Background and Objectives:</i> The conflicting findings in existing studies and insufficient evidence highlight the necessity for additional research on the relationship between sleep quality and coronary artery disease (CAD) in elderly acute coronary syndrome (ACS) patients. We aimed to investigate the association between sleep quality and the CAD severity of in geriatric patients with ACS. <i>Materials and Methods:</i> This retrospective observational cohort study analyzed data from 308 patients aged 65 years and older admitted with ACS who had undergone coronary angiography between May 2022 and June 2025 at a tertiary cardiology department. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI) at the 6-month follow-up, with scores > 5 indicating poor quality. CAD severity was quantified by SYNTAX score from angiograms. The primary endpoint was the relationship between PSQI and SYNTAX score, with secondary analyses concerning factors associated with clinical outcomes. <i>Results:</i> Poor sleep quality (PSQI > 5) was associated with higher SYNTAX scores (<i>p</i> < 0.001), lower ejection fraction (<i>p</i> < 0.001), higher CRP (median 5.1 vs. 4.05, <i>p</i> = 0.029), NT-proBNP (median 748.5 vs. 595, <i>p</i> = 0.034), lower glomerular filtration rate (<i>p</i> = 0.025), and higher hypertension prevalence (<i>p</i> = 0.034). ST-elevation myocardial infarction was more common in subjects with poor sleep. Multivariable logistic regression identified hypertension (<i>p</i> = 0.011), reduced ejection fraction (<i>p</i> = 0.030), STEMI (<i>p</i> = 0.045), intermediate SYNTAX (<i>p</i> = 0.003), and high SYNTAX (<i>p</i> = 0.009) as associated factors of poor sleep. <i>Conclusions:</i> Poor sleep quality is independently linked to greater CAD severity in geriatric ACS patients. This is a modifiable risk factor that can reduce morbidity and mortality in this high-risk group.