IMPACT OF SLEEP DISORDER ON OVERALL HEALTH

Abstract

Sleep disorders have several impacts on overall health. With the increase in sleep disorders over the last few years, there is a need to identify some of the most common causes of sleep disorders and if factors such as age, gender, ethnicity and social status may be considered as risk factors. Different studies have been done to determine the impacts of sleep disorders on an individual’s overall health. The central focus of this research is to review some of these studies, and come up with a conclusion that tends to bring out these health impacts that are associated with sleep disorders, particularly, sleep deprivation.

Introduction

Sleep is considered as a biological process and it has regularly been essential for good life and optimal health (Wells & Vaughn, 2012). Sleep has been essential in controlling brain functioning, and even in other biological and systematic processes such as metabolism, regulation of appetite, and improving one’s immunity against a number of diseases, especially in children. Normally, a good sleep is associated by the duration of the sleep, the quality, and regularity among other factors. Although a number of studies, and even media, have covered the health benefits of sleep, more than 70 million individuals in the US are still suffering from sleep-related disorders, and moreover, in Europe, approximately 45 million people are also victims of these disorders. For instance, a study conferred that of all the car accidents that occur in the US, 20% are as a result of lack of enough sleep, or other disorders associated wit either too much sleep or lack of enough sleep (Palma et al., 2013).

There are a number of consequences that may arise as a result of sleep loss and other sleep-related disorders. As conveyed by Ming et al. (2011), the most common consequences that may be related to sleep include judgment errors, which may lead to disastrous events. On the other pedestal, some of the less visible consequences of sleep disorder include increased mortality and morbidity rate, car accidents and injuries, QoL, the well-being of the family, and utilization of healthcare services among the affected persons. Some of these consequences may arise a few minutes after having less hours of sleep, or too much sleep. However, there are some long-term impacts of sleep, for instance, obesity and hypertension. Sleeping for a longer duration enhances the body’s inactivity and this is greatly associated with obesity, which may also give chance to the development of hypertension and other cardiovascular complications. According to Ming et al. (2011), there are approximately 90-100 sleep disorders which may result from factors such as environmental factors, psychosocial issues, and other medical conditions. Although the number of sleep disorders is on an increasing trend, these disorders may be classified into not obtaining the recommended amount of sleep, or having low quality of sleep, which is referred to as sleep deprivation, having disrupted sleep, also known as sleep fragmentation and having difficulties maintaining sleep, middle insomnia and other cases that may arise during sleep including sleep apnea, as well as restless legs syndrome among others (Ming et al., 2011).

Sleep has been considered to be one of the greatest components of a good health. Studies have focused on determining some of the most common disorders that may arise due to either lack of enough sleep, or too much sleep. The average number of hours of sleep that a person should have on a day is 8 hours. However, the increase in the number of individuals, especially in the US, has led to an increase in the rates of unemployment. This has adverse effects on one’s sleeping hours since people have to work for longer hours to make a living, a case that has led to high rates of occurrence of sleep disorders. These sleep disorders cause a number of health problems to the human body, and as a result, there is a need to design strategies that can be implemented to ensure that the rates of sleep disorders is reduced, especially in the US. This study will review some of the impacts of sleep disorders on overall health, as well as the most effective preventive strategies that can be used to ensure that individuals do not have disrupted sleep.

Methodology

This study reviews previous studies that are based on sleep deprivation and its impacts on an individual’s overall health. The researcher sampled past papers using convenience sampling followed by simple random sample in each of the obtained convenience samples. The researcher also used some keywords to search for studies in this specific field. These keywords supported the fact that convenience sampling was used to collect the required information. These studies formed the sample, and the sample consisted of 100 studies. Of these 100 literature reviews, only 65 aligned with this study’s objectives and as a result, n=65. This sample size is large enough, as per the central limit theorem, and as a result, the findings obtained may be used to generalize on the entire population of individuals who may be affected by sleep disorders. Although a larger sample size usually leads to more reliable and valid results, after selecting the 65 research articles, there was a need to specifically look for studies that were based on sleep deprivation and as a result, simple random sampling was used at this stage to select only 10 of these articles. This study is therefore, considered as a review of these 10 sampled articles, although a comparison and findings, also relate with results obtained from other previous studies, in the same field.

Results

According to Shapiro & Dement (1993), there has been an increase in the rates at which sleep disorders affect the health and well-being of the victims. This study found out that one in every seven persons in the US is affected by sleep disorders. The findings from this article portray the fact that some of the sleep disorders that greatly impact human beings’ health and overall well-being include sleep walking, RLS, narcolepsy, sleep terrors and insomnia among others. Another study by Ram et al. (2010) found out that there is a rapid increase in the prevalence and incidence of sleep disorders in the US. As a result, some of the most prevalent sleep disorders include apnea, RLS, and insomnia. According to this study, there are a number of factors that relate to this prevalence of these sleep disorders and some of these include age, gender, and race, and this implies that the susceptibility of sleep disorders differs from one person to the other.

Another significant result that was obtained from this review is that most studies are now focusing on sleep deprivation which is considered as a risk factor for a number of neurological diseases including stroke, multiple sclerosis, AD, and epilepsy among others. However, the study also found out that a number of findings have established that sleep disorder is regarded as a protective measure against the development and progression of Parkinson’s disease. A random survey of around 9003 British adults, children and youths found out that sleep disorder is mainly common among the young, aged 8-34 years, and among the adults who are aged over 65 years. In a similar study, those who had the recommended duration of sleep, 7-9 hours, had lower rates of illnesses, and this may be attributed to the fact that sleep also boosts one’s immune system. Another study by Ram et al. (2010) also found out that sleep disorders was one of the leading causes of road accidents in the US. The results obtained from this study is represented by the graph below.

Figure 1: Rate of traffic accidents that result from sleep disorders

A study done by Alhola & Polo-Kantola (2007) found out that wakefulness is a widespread phenomenon that has been linked with a number of disorders. For instance, wakefulness is considered to be a result of sleep restriction or deprivation. The study found out that there was a significant relationship between partial and total SD on an individual’s cognitive performance. For instance, SD is able to interfere with a person’s working memory, and even decision making capabilities. Similarly, other studies also found a strong positive correlation between sleep disorders and lack of enough sleep. For instance, this study found out a p-value of 0.0003, while trying to depict whether sleeping for less hours is associated with care accidents. It was found out that of all the participants, those who slept for short duration of time were likely to get involved in car accidents. On the other hand, those who slept for more than 6.5-8 hours per day, were less likely to be involved in car accidents, unless if the accident occurs as a result of other causes.

Discussion: Sleep disorders and car accidents

A study done by Cochen et al. (2009) asserted that there exists a strong positive correlation between sleep disorders and an increase in the occurrence of car accidents specifically in the US. Furthermore, in the US alone, National Highway Traffic Safety Administration estimates that sleep disorders result into drowsy driving and this is responsible for over 72,000 car crashes, more than 40,000 injuries as well as over 800 deaths annually. Furthermore, studies have also suggested that more than 50,000 deaths occur each year as a result of accidents. However, of these deaths, close to 13% are caused by falling asleep while driving, which is attributed to the presence of one or more sleep disorders. This study also conveyed that sleepiness without necessarily falling asleep is more dangerous, and may further result into additional car crushes and injuries and this is as a result of impaired vigilance. Studies also support the fact that falling asleep and experiencing excessive sleepiness mainly occur to drivers who go for long distances and while driving in low traffic areas, which results into little motor activity.

Impact of sleep disorders on glucose metabolism

According to Briançon-Marjollet et al. (2015), there is a correlation between sleep disorders and glucose metabolism, particularly, endocrine and molecular metabolisms. Inadequate sleep duration, together with irregular sleep may impair an individual’s cognitive performance. However, this also interferes with one’s sleep quality and quantity, which are significant determinants of whole body metabolism. Studies have also suggested that sleep impairments may lead to the development of Type 2 Diabetes Mellitus (T2DM), as well as an increase in obesity epidemic.

A number of large scale cross-sectional epidemiological studies have also depicted that in hypertensive patients and pregnant women, lack of enough sleep is associated with the development of T2DM, or impairments in glucose tolerance, and this is more common in women as asserted by Briançon-Marjollet et al. (2015). Furthermore, short sleep duration, which leads to development of sleep disorders, is also associated with a number of pre-diabetic features, for instance, resistance to insulin levels and whole body indices, heightening of postprandial glucose as well as fasting hyperglycemia among others. Additionally, sleep disorders also have negative impacts on glycemic control. Another health impact of sleep disorders is that it regulates an individual’s appetite. For instance, short sleep duration has been considered as an independent risk factor for weight gain, as this leads to accumulation of fats in the abdomen. Biologically, this has been evidenced by a number of studies and due to the fact that those who sleep for short hours usually prefer taking foods rich in carbohydrates and fats which increase their caloric intake by approximately 20% per day (Briançon-Marjollet et al., 2015).

Sleep and ageing

Studies have extensively determined the association between sleep and ageing. Most significantly, a number of studies have focused on the impacts of sleep on ageing. The quality and quantity of sleep should be taken into consideration to reduce any sleep complications that may arise. For instance, a study done by Stanley (2005) depicts that there is a positive relationship between short sleep duration and ageing. This study suggests that individuals who have short duration of sleep usually age faster than those who sleep for the recommended sleeping duration of averagely 8 hours per day. According to this study, normal sleep patterns vary across an individual’s life-course and most significantly, elderly and ageing individuals reported cases of more disrupted, and less efficient sleep. This results into an increase in daytime somnolence, which may greatly impact daytime performance, as well as overall health of the victim.

Effects of sleep disorder on PD

Although most studies have suggested that there is a relationship between sleep disorders and an individual’s overall health, a number of studies have also suggested that there exists an association between sleep disorder and non-motor symptoms of Parkinson’s disease. According to the study by Neikrug et al. (2013), sleep disorders are regarded as risk factors for fatigue complaints, depressive symptoms, poor QoL, and decline in cognitive performance among others. Furthermore, the study also depicted that if the number of sleep disorders is increased, then an individual may end up experiencing non-motor symptom impairment. In this study, PD patients were used as the study participants and it was found that non-motor PD symptoms were largely predicted by the presence of comorbid sleep disorders.

Impact of sleep deprivation on cognitive performance

According to a study by Alhola & Polo-Kantola (2007) conveys that sleep disorders have greatly impacted cognitive performance of the affected individuals. This is because individuals having short sleep durations usually develop working memory impairments, and this reduces the cognitive performance of the victims. However, the study only focuses on one population, and very few studies have been done to compare these outcomes, if several factors such as age, gender, ethnicity, and social status are varied. Furthermore, several studies have also supported the fact that aging people’s cognitive performance is generally poor, however, SD lowers these persons’ cognitive performance. Furthermore, gender is also a factor to be considered while studying the significat impacts of SD on cognitive performance since this study confers that women are more likely to endure prolonged wakefulness more than their male counterparts. Individual traits also help in tolerating SD, although this remains biologically unclear. As a result, further studies should be carried out to investigate the biological evidence that support the existence of sleep disorders among various populations, as well as the reasons behind one population being more susceptible to SD than the other populations. For instance, studies should focus on why ageing individuals develop SD more frequently than the young individuals. Additionally, more studies should also be centered on determining the most effective preventive measures that can be implemented to reduce the health impacts that result from these sleep disorders.

Conclusion

Over the last few years, there has been an increase in sleep disorders. This has specifically been attributed to increase in population, modernization, as well as an increase in unemployment rates in the US. A number of sleep disorders have been on the rise including insomnia, sleep deprivation, and apnea among others. Most researchers have linked sleep disorders with a number of variables, however, all these are centered around human health. For instance, studies have linked sleep disorders with the development of T2DM, cognitive performance, ageing, and non-symptomatic Parkinson’s disease among others. As a result, there is a need for individuals to avoid wakefulness and have quality and quantity sleep, where quality implies having regular sufficient sleep while on the other pedestal, quantity implies sleeping for the recommended average of 8 hours per day. Furthermore, there is also a need to design some of the most effective strategies that can be used to ensure that sleep disorders do not adversely affect the victims through development of diseases such as obesity, Type 2 Diabetes Mellitus, as well as hypertension among others, some of which may result into terminal diseases. Although most sleep disorder cases are considered as an individual’s choice or lifestyle, ageing adults should be educated on the significance of enough and quality sleep, especially on QoL, as well as on their overall health.

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