The Association Between Obstructive Sleep Apnea Characterized by a Minimum 3 Percent Oxygen Desaturation or Arousal Hypopnea Definition and Hypertension

Abstract

Study objectives: The association between obstructive sleep apnea (OSA) and hypertension in prior studies has been determined using a definition of hypopnea requiring a 4% O₂ desaturation. However, the American Academy of Sleep Medicine (AASM) recommends using a 3% O₂ desaturation or an arousal. This analysis assesses the relationship between OSA and hypertension utilizing the AASM recommended definition and the 2018 American College of Cardiology/American Heart Association hypertension guidelines.

Methods: Data from 6113 participants from the Sleep Heart Health Study were analyzed. The AASM recommended apnea-hypopnea index (AHI) was classified into 4 categories of OSA severity: < 5, 5 to < 15, 15 to < 30 and ≥ 30 events/h. Three definitions of hypertension were used: elevated (> 120/< 80 or use of hypertension medications [meds]), stage 1/stage 2 (> 130/80 or meds), stage 2 (> 140/90 or meds). Data were analyzed using logistic regression controlling for demographics, smoking and body mass index. Multiple linear regression analysis assessed the relationship between natural log AHI, and systolic and diastolic blood pressure controlling for the same covariates.

Results: For all definitions of blood pressure elevation, increasing OSA severity was associated with greater likelihood of an elevated or hypertensive status in fully adjusted models (odds ratio [95% confidence interval]): elevated 1.30 (1.09-1.54), 1.39 (1.13-1.70) 1.69 (1.29-2.13); stage 1/2: 1.25 (1.06-1.47), 1.32 (1.10-1.59), 1.53 (1.23-1.91); stage 2: 1.07 (0.91-1.25), 1.21 (1.01-1.44), 1.37 (1.11-1.69) for AHI 5 to < 15, 15 to < 30 and > 30 events/h (< 5 events/h reference). Linear regression found that AHI was associated with both systolic and diastolic blood pressure in fully adjusted models.

Conclusions: Use of the AASM recommended definition of hypopnea as a component of the AHI is associated with the presence of hypertension.

Citation: Budhiraja R, Javaheri S, Parthasarathy S, Berry RB, Quan SF. The association between obstructive sleep apnea characterized by a minimum 3 percent oxygen desaturation or arousal hypopnea definition and hypertension. J Clin Sleep Med. 2019;15(9):1261-1270.

Keywords: apnea-hypopnea index; blood pressure; hypertension; obstructive sleep apnea.

Figure 1. Graphic representations of the association of LnAHI + 0.1 and either systolic or diastolic blood pressure for each of the models shown in Table 6.

Values for BMI, sex, smoking, race/ethnicity and age were fixed at their respective means in order to generate an illustrative 2-dimensional plot. The values for LnAHI + 0.1 were converted to the AHI and shown as an alternative x-axis to facilitate visualization. (A) Estimated systolic blood pressure as a function of Ln AHI defined by a 3% desaturation or arousal for hypopneas. (B) Estimated diastolic blood pressure as a function of Ln AHI defined by a 3% desaturation or arousal for hypopneas. (C) Estimated systolic blood pressure as a function of Ln AHI defined by a 4% desaturation for hypopneas. (D) Estimated diastolic blood pressure as a function of Ln AHI defined by a 4% desaturation for hypopneas. (E) Estimated systolic blood pressure as a function of Ln AHI defined by a 3% desaturation or arousal for hypopneas in participants who had an AHI < 5 events/h using an AHI definition defined by a 4% desaturation for hypopneas. (F) Estimated diastolic blood pressure as a function of Ln AHI defined by a 3% desaturation or arousal for hypopneas in participants who had an AHI < 5 events/h using an AHI definition defined by a 4% desaturation for hypopneas.