Mild obstructive sleep apnea increases hypertension risk, challenging traditional severity classification

Abstract

Study Objectives: The association of mild obstructive sleep apnea (OSA) with important clinical outcomes remains unclear. We aimed to investigate the association between mild OSA and systemic arterial hypertension (SAH) in the European Sleep Apnea Database cohort. Methods: In a multicenter sample of 4,732 participants, we analyzed the risk of mild OSA (subclassified into 2 groups: MildAHI 5-<11/h (apnea-hypopnea index [AHI], 5 to <11 events/h) and mildAHI 11-<15/h (AHI, .11 to <15 events/h) compared with nonapneic snorers for prevalent SAH after adjustment for relevant confounding factors including sex, age, smoking, obesity, daytime sleepiness, dyslipidemia, chronic obstructive pulmonary disease, type 2 diabetes, and sleep test methodology (polygraphy or polysomnography). Results: SAH prevalence was higher in the mildAHI 11-<15/h OSA group compared with the mildAHI 5-<11/h group and nonapneic snorers (52% vs 45% vs 30%; P < -001). Corresponding adjusted odds ratios for SAH were 1.789 (mildAHI 11-<15/h; 95% confidence interval [CI], 1.49.2.15) and 1.558 (mildAHI 5-<11/h; 95%, CI, 1.34.1.82), respectively (P <15/h OSA remained a significant predictor for SAH both in the polygraphy (odds ratio, 1.779; 95% CI, 1.403.2.256; P <150-events/h range. These findings potentially introduce a challenge to traditional thresholds of OSA severity and may help to stratify participants with OSA according to cardiovascular risk.