Utility of overnight pulse oximeter as a screening tool for sleep apnea to assess the 8-year risk of cardiovascular disease: Data from a large-scale bus driver cohort study
Introduction
Cardiovascular disease (CVD) is not only the number one cause of death worldwide, but it is also one of the compensable work-related diseases [1], [2]. Therefore, except for the common CVD risk factors including smoking, hypertension, diabetes, hyperlipidemia, obesity, physical inactivity or diet [1], [2], the work environment factors in professional drivers, such as irregular work shifts, long hours of driving, sedentary restricted postures, long-term sleep deficiency, noise and chemical exposures [3], [4], [5], [6], [7], [8], also have increased the probability of developing CVD [6], [9], [10], [11], [12].
Recently, sleep-disordered breathing (SDB) is increasingly being recognized as an important factor contributing to the burden of CVD [13], [14], [15], [16], [17], [18], [19]. SDB is a sleep disorder that involves cessation or a significant decrease in airflow in the presence of breathing effort, and causes recurrent oxyhemoglobin desaturations and arousals from sleep. SDB has been shown to be more common among professional drivers, which is likely because physical inactivity or unhealthy diet choices cause obesity, and irregular work schedules or long working hours cause circadian rhythm disruption and chronic sleep deficiency [3], [4], [20]. Previous studies identified that about 28.2% of professional drivers from the USA [21], 15.8% of professional drivers from Australia [20], and 10% of bus drivers from both the UK [22] and Hong Kong [23] suffered from sleep apnea, in contrast to 3%–7% prevalence of OSA within the general male population [24]. It is a significant labor health concern when one considers the relatively high and rising prevalence of SDB in this high-risk occupation.
Importantly, SDB is a treatable disease; therefore, studies on whether or not SDB contributes to or exacerbates CVD, could support a novel target for cardiovascular risk reduction in professional drivers. However, reviewing a previous study that related to the effect of SDB on CVD development in professional drivers has never been systematically investigated. Additionally, several problems were shown in this research field, including an incomplete CVD data collection, small sample sizes, and poor control for confounding factors, which limited the assessment of an independent pathogenic role for SDB, and did not show clear causal association. Thus, we performed a perspective cohort study to evaluate the effectiveness of overnight pulse oximeter as a sleep apnea screening tool to assess the 8-year risk of CVD events. We hypothesized that the oxygen desaturation index would predict CVD and CVD events such as hypertensive disease, ischemic heart disease (IHD), cerebrovascular disease, diseases of arteries, arterioles, and capillaries, and congestive heart failure (CHF), and that the associations would persist after adjusting for CVD risk factors.
Section snippets
Study population
The study procedure is presented in Fig. 1. The Taiwan Bus Driver Cohort Study (TBDCS) included 1650 professional drivers from the largest transportation companies in Taiwan. First, we used this cohort to link the Driving Hours Dataset (total number of records = 1,518,350 person-times) based on the Event Data Recorder from 2005 to 2007. We selected 1037 professional drivers whose total driving period exceeded 100 days during the 3 years after undergoing an assessment questionnaire interview and
Results
The descriptive statistics of the all drivers in terms of work patterns and demographic characteristics are presented in Table 1. Most of the cohort subjects were between 35 and 44 years old (42.7%), one-quarter of the cohort (27.9%) had more than 8 years of driving experience, and almost half of the subjects worked with irregular shifts in the baseline. About 50% of the cohort subjects were obese (BMI ≥ 30 kg/m2), 19% of subjects had a drinking habit (22.8%), and more than half of the subjects had
Discussion
This is the first large professional driver cohort study to show that nocturnal oxygen saturation is independently associated with future CVD events. The major finding of this study was that ODI levels are useful in the prediction of 8-year CVD risks, even adjusting for CVD risk factors. Furthermore, the ODI levels had an increase of HR for other CVD events such as cardiovascular disease (not including hypertensive disease), and hypertensive disease (not including essential hypertension).
Conclusion
In a large cohort of professional drivers, nocturnal oxygen saturation for a sign of SDB is an independent risk factor for increased future CVD events. The overnight pulse oximeter is a useful sleep apnea research tool in large study populations for assessing the risk of CVD. Further research should be conducted regarding measures to prevent against SDB in order to reduce future CVD risk among professional drivers.
The following are the supplementary data related to this article.
Funding sources
This study was partly supported by the National Health Research Institutes of Taiwan (98-EO-PP01, 99-EO-PP01, 00-EO-PP01, EO-101-PP-01, EO-102-PP-01 and EO-103-PP-01) and Institute of Occupational Safety and Health (IOSH96-M102 and IOSH97-M102), Taiwan.
Disclosures
None declared.
Conflicts of interest
None of the authors have any potential, perceived or real conflicts of interest.
Acknowledgments
The authors thank the administrators and drivers in the Bus Company for their participation and cooperation. The current analysis was based on data provided by the Health and Welfare Data Science Center, Ministry of Health and Welfare, Executive Yuan, Taiwan. The funder had no role in the study's design, data collection and analysis, decision to publish, or preparation of the manuscript.
References (42)
- et al.
Sleepiness/fatigue and distraction/inattention as factors for fatal versus nonfatal commercial motor vehicle driver injuries
Accid. Anal. Prev.
(2005) - et al.
An investigation of the relationship between organizational climate and professional drivers' driver behaviours
Saf. Sci.
(2010) - et al.
Shift work and arteriosclerosis risk in professional bus drivers
Ann. Epidemiol.
(2010) - et al.
Long-term cardiovascular outcomes in men with obstructive sleep apnoea–hypopnoea with or without treatment with continuous positive airway pressure: an observational study
Lancet
(2005) - et al.
Obstructive sleep apnea and risk of cardiovascular disease and all-cause mortality: a meta-analysis of prospective cohort studies
Int. J. Cardiol.
(2013) - et al.
Prevalence and impact of central sleep apnea in heart failure
Sleep Med. Clin.
(2007) - et al.
Work-related cardiovascular disease risk factors using a socioecological approach: implications for practice and research
Eur. J. Cardiovasc. Nurs.
(2012) Cardiovascular diseases (CVDs). World Health Organization 2015
- et al.
Stress, fatigue, health, and risk of road traffic accidents among professional drivers: the contribution of physical inactivity
Annu. Rev. Public Health
(2006) - et al.
Bus driver well-being review: 50 years of research
Transport. Res. F
(2006)
Increased plasma homocysteine levels in shift working bus drivers
Occup. Environ. Med.
Myocardial infarction among professional drivers
Epidemiology
Incidence of myocardial infarction and mortality from specific causes among bus drivers in Sweden
Int. J. Epidemiol.
Myocardial infarction among male bus, taxi, and lorry drivers in middle Sweden
Occup. Environ. Med.
Risk of coronary heart disease in middle-aged male bus and tram drivers compared to men in other occupations: a prospective study
Int. J. Epidemiol.
Obstructive sleep apnea as a risk factor for stroke and death
N. Engl. J. Med.
Sleep-disordered breathing and mortality: a prospective cohort study
PLoS Med.
Obstructive sleep apnea as a risk factor for coronary events or cardiovascular death
Sleep Breath.
Increased incidence of cardiovascular disease in middle-aged men with obstructive sleep apnea: a 7-year follow-up
Am. J. Respir. Crit. Care Med.
Obstructive sleep apnea–hypopnea and incident stroke: the sleep heart health study
Am. J. Respir. Crit. Care Med.
Sleepiness, sleep-disordered breathing, and accident risk factors in commercial vehicle drivers
Am. J. Respir. Crit. Care Med.
Cited by (10)
Preoperative oximetry-derived hypoxemia predicts postoperative cardiovascular events in surgical patients with unrecognized obstructive sleep apnea
2022, Journal of Clinical AnesthesiaCitation Excerpt :Gami et al. showed the lowest SpO2 of 76% as a predictor for sudden cardiac death [22]. Similarly, Wu et al. showed that ODI is associated with eight-year cardiovascular risk in professional drivers [23]. We found an optimal cut-off of CT90 ≥ 20 min in surgical patients, similar to the best threshold of >22 min to identify heart failure patients with all-cause mortality [24].
Pulse oximeter-based machine learning models for sleep apnea detection in heavy vehicle drivers
2022, Autonomous and Connected Heavy Vehicle TechnologyThe 3% Oxygen Desaturation Index is an Independent Risk Factor for Hypertension Among Children with Obstructive Sleep Apnea
2022, Nature and Science of SleepPECULIARITIES OF THE WORKPLACE ENVIRONMENT HEALTH EFFECTS IN THE MUNICIPAL TRANSPORTATION EMPLOYEES
2022, Georgian Medical News