Prevalence of Sleep Apnea among Japanese Industrial Workers Determined by a Portable Sleep Monitoring System

Abstract

We developed a new portable sleep monitoring system and studied the prevalence of sleep apnea syndrome among Japanese industrial workers. This device assessed three kinds of parameters: nasal airflow, tracheal sound and electrocardiogram (ECG), and digitally stored the clock time of the onset of apnea, apnea duration and R-R intervals by a built-in microcomputer. After monitoring, the portable sleep monitor was connected to a host computer, and apneic episodes, the so-called ‘apnea index’ as apneic episodes corrected by measuring time (‘AI’) and R-R intervals were analyzed. In 170 inpatients referred to our sleep clinic, sleep monitoring by this device was performed simultaneously with all-night polysomnography, and the sensitivity and specificity of this device was determined under different criteria of the apnea index (AI) (AI > 5,10, 15 and 20 episodes/h) by polysomnography. In all AI criteria, the sensitivity was more than 90%, and the specificity was also reasonably high. Using this system, successive 2-night home sleep monitoring was performed on 168 healthy workers in one Japanese industrial company, and 159 people (140 males; 19 females) who had successful monitoring were analyzed. The percentage of persons who had ‘AΓ of more than 10 episodes/h was 7.5%. There were no significant correlations between ‘AI’ and age, body weight or scores estimated by sleep questionnaires. These results suggest that even in people who are seemingly healthy significant apneic episodes could be detected by the portable home sleep monitoring system. This system may therefore be useful in evaluating the occurrence of sleep apnea syndrom in general populations.

Prevalence and Correlates of Sleep‐Disordered Breathing in Older Men: Osteoporotic Fractures in Men Sleep Study

“…The magnitude of this association is similar to that reported in the SHHS, demonstrating that 46% of participants with an RDI of 15 or greater had sleepiness symptoms using the same definition of sleepiness used in the current analysis (ESS score > 10). 34 Although the specificity and sensitivity of daytime sleepiness may be less in older people with many comorbidities, the evidence for significantly greater odds of daytime sleepiness with SDB underscores the importance of assessing this symptom in relationship to SDB in older people.…”

“…The magnitude of this association is similar to that reported in the SHHS, demonstrating that 46% of participants with an RDI of 15 or greater had sleepiness symptoms using the same definition of sleepiness used in the current analysis (ESS score > 10). 34 Although the specificity and sensitivity of daytime sleepiness may be less in older people with many comorbidities, the evidence for significantly greater odds of daytime sleepiness with SDB underscores the importance of assessing this symptom in relationship to SDB in older people.By examining the strength of the associations between risk factors and comorbidities according to definitions that differentiated central from obstructive events, these analyses provided further evidence that CAs and OAs were associated with a distinct constellation of risk factors and outcomes. In particular, an elevated CAI was associated with advancing age and with heart failure but not with indices of obesity.…”

Japanese versus USA clinical services for sleep medicine

“…Finally, the prevalence of SDB could be lower in Japan. We doubt, however, that this is the case because previous studies, although not comprehensive in nature, demonstrated a similar prevalence of sleep apnea in the two countries 7–9 …”

“…We doubt, however, that this is the case because previous studies, although not comprehensive in nature, demonstrated a similar prevalence of sleep apnea in the two countries. [7][8][9] We speculate, therefore, that the proportion of undiagnosed SDB and the other sleep disorders must be greater in Japan than in the USA. Current data suggest that untreated OSAHS leads to sleepiness, 10 decreased quality of life, 11 automobile accidents, 12 systemic hypertension, 13 and cardiac disease.…”

Cephalometric analysis parameters related to the severity of sleep-breathing disorders

“…The prevalence rate of sleep‐breathing disorders (SBD) in the Japanese population appears to be lower than that in Caucasians because marked obesity is rare in the Japanese 1–5 . However, it has been suggested that over 3% of the adult Japanese population suffer from an SBD, and it has been reported that the prevalence of the disease is comparatively high 6–8 . These reports suggest that if obesity is much less frequently seen in the Japanese compared with Caucasians, other contributing factors for developing an SBD must exist for the Japanese 9–15 …”