Nocturnal Intermittent Hypoxia and Metabolic Syndrome; the Effect of being Overweight: the CIRCS Study

Abstract

Aim:We investigated whether nocturnal intermittent hypoxia, a surrogate marker for obstructive sleep apnea, is associated with metabolic syndrome and its components among Japanese. Methods: We examined 1,710 male and 2,896 female community-dwelling Japanese aged 40 to 69, who participated in annual cardiovascular examinations and investigations of sleep. Nocturnal intermittent hypoxia was estimated based on a 3% oxygen desaturation index measured with pulse-oximetry during sleep. No, mild and moderate-to-severe nocturnal intermittent hypoxia were defined by 5, 5 to 15 and ≥ 15 events/hour, respectively. Metabolic syndrome was defined by modified criteria of the Adult Treatment Panel guidelines. Results: Compared with no nocturnal intermittent hypoxia, the multivariable odds ratio of metabolic syndrome was 1.9 (95% confidence interval: 1.6 − 2.4) for mild and 3.2 (2.2 − 4.7) for moderate-tosevere nocturnal intermittent hypoxia among men; 2.6 (2.1 − 3.4) and 5.8 (3.4 − 9.8) among women, respectively. When stratified by overweight status (body mass index ≥ 25 kg/m 2 ), the multivariable odds ratio of two or more metabolic risk factors (other than overweight) associated with moderateto-severe nocturnal intermittent hypoxia was 1.9 (1.2 − 3.1) among non-overweight subjects and 1.4 (0.9 − 2.1) among overweight subjects (p for interaction 0.002). Conclusions: Nocturnal intermittent hypoxia was associated with the accumulation of metabolic risk factors, especially among non-overweight individuals.

Nocturnal Falls of Adiponectin Levels in Sleep Apnea with Abdominal Obesity and Impact of Hypoxia-Induced Dysregulated Adiponectin Production in Obese Murine Mesenteric Adipose Tissue

“…Previous studies demonstrated the possible association between sleep apena and visceral obesity 8,[17][18][19] 20) , and recent studies reported that obese subjects with sleep apnea also suffer from daytime hypoadiponectinemia 21,22) . Our recent study showed daytime hypoadiponectinemia and nocturnal falls in circulating adiponectin concentrations in patients with severe OSAS, in part due to hypoxic stress 9) .…”

Relationships between Nocturnal Intermittent Hypoxia, Arterial Stiffness and Cardiovascular Risk Factors in a Community-based Population: The Toon Health Study

“…The median value of 3% ODI was 5.4 on the first night and 4.8 on the second night (p for difference = 0.95, Wilcoxon's signed-rank test). Spearman's rank correlation coefficient was 0.81 (p＜0.001) 25) .…”

“…Because apneic episodes do not always induce oxygen desaturation, we were unable to accurately detect the presence of very mild NIH. However, the sensitivity and specificity of pulse oximetry are high 29) , as well as the reproducibility 25) . In addition, the convenience of pulse oximetry for assessing intermittent hypoxia at home and its utility in providing an early diagnosis and treatment for patients with NIH have been documented 7,43) .…”

“…The mean body mass index (BMI) of Eastern Asia is much lower than the rest of the world 24) ; OSA was found to affect cardiovascular risk factors more strongly among lower BMI populations 25) . So far, there have been no studies on the assessment of NIH and arterial stiffness by using CAVI in a communitydwelling population.…”

The role of pulse oximetry in chiropractic practice: a rationale for its use

“…It has been recommended that patients at risk for hypoxic conditions be monitored using pulse oximetry. 12,14,[33][34][35][36][37] Hypoxia is commonly found in the elderly 38 and those at risk for coronary vascular disease, 39 coronary artery disease, 39 sleep disordered breathing, 39 disorders of balance, hypertension, 39 chronic migraines, and anxiety and mood disorders, 39 all of which can be present within a population of chiropractic patients. See Table 1 for a complete list of clinical signs and symptoms indicating use of pulse oximetry.…”