Hypertension is associated with undiagnosed obstructive sleep apnea (OSA) during rapid eye movement (REM) sleep in a population cohort of men

Introduction: Evidence for a relationship between OSA and hypertension from clinic- and population-based studies is conflicting and the clinical significance of OSA during REM sleep is uncertain. We examined the longitudinal association of hypertension with undiagnosed OSA and OSA during REM sleep. Methods: The Men Androgen Inflammation Lifestyle Environment and Stress (MAILES) Study is a population-based biomedical cohort of men aged ≥ 35 y in Adelaide, South Australia. At follow-up (2010–12, mean 56 months), 837 men without previously diagnosed OSA underwent home-based full unattended polysomnography (Embletta X100). Of these, 739 men recorded ≥30 min of REM sleep. Hypertension (systolic ≥140 mm Hg and/or diastolic ≥90 mm Hg or use of medication for hypertension) was identified at baseline and follow-up. Incident hypertension was defined as hypertension at follow-up in men who were normotensive and not on medication at baseline. Results: Prevalent (63.8% c.f. 46.0%) and incident (34.5% c.f. 23.5%) hypertension were significantly more common in men with OSA [apnoea-hypopnea index (AHI) ≥ 10/h] compared to men without OSA. In analyses adjusted for age, smoking, alcohol use, waist circumference, and supine sleep position, moderate (AHI 20–29/h) and severe OSA (AHI ≥ 30/h) were independently associated with prevalent hypertension only. REM AHI ≥ 30/h was significantly associated with prevalent [odds ratio (OR): 2.75, 95% CI: 1.63–4.66] and incident hypertension (2.36, 1.06–5.24) independent of Non-REM AHI. OSA during Non- REM sleep was not associated with hypertension. In the subgroup with Non-REM AHI < 10, REM AHI ≥ 20/h occurred in 20.6% (n = 79). REM AHI ≥ 20/h was associated with prevalent (1.99, 1.09–3.62) but not incident hypertension (1.94, 0.72–5.21, p = 0.18) Oxygen desaturation index >16/h was also associated with prevalent (p < 0.05), and incident hypertension (p = 0.067). Conclusions: Men with severe REM OSA were significantly more likely than those without OSA to have developed hypertension. CPAP therapy that does not extend into later sleep cycles leaving REM OSA largely untreated may have implications for the clinical management of hypertension and outcomes of trials of CPAP for hypertension.