Sleep-related breathing disorder in a Japanese occupational population and its association with exercise-induced blood pressure elevation

Sleep-related breathing disorder (SRBD) and exercise-induced blood pressure (BP) elevation are known risk factors for hypertension. However, the relation between them remains unknown. This cross-sectional study examined the relationship between SRBD and exercise-induced BP elevation in a Japanese occupational population. Using the 3% oxygen desaturation index (3%ODI) obtained by a portable monitor for overnight saturation of percutaneous oxygen (SpO2), participants were classified into low (0 ≤ 3%ODI < 5), medium (5 ≤ 3%ODI < 15), and high (15 ≤ 3%ODI) 3%ODI groups. We included employees who had undergone an exercise electrocardiogram test after monitoring for overnight SpO2. In total, 928 employees were included. The median age of the participants was 50 years, 96% were male, the mean body mass index was 23.9 ± 3.1 kg/m2, and the median 3%ODI was 4.9 (interquartile range: 1.6–6.5). Among them, 30% and 5% were categorized into the medium and high 3%ODI groups, respectively. At a median exercise intensity of 10.1 METs, BP changed from 124 ± 16/76 ± 12 mmHg before to 183 ± 26/85 ± 14 mmHg after exercise, with a mean systolic BP change of +59 ± 23 mmHg (−20 to +128 mmHg). When we defined systolic BP change of +60 mmHg or more as exercise-induced BP elevation, the odds ratio for exercise-induced BP elevation increased significantly with higher 3%ODI levels after multivariate adjustment for parameters including current use of antihypertensive medication and maximal exercise intensity (p for trend = 0.01). Higher 3%ODI was significantly associated with higher prevalence of exercise-induced BP elevation, suggesting sympathetic hyperactivity occurs in SRBD patients. Our results suggest the potential presence of SRBD should be considered in individuals with exercise-induced BP elevation.