Inadequate Sleep: Increasing Risk Factor for Heart Diseases

Sleep is a natural, periodically recurring, state of mind and body. It is characterized by reduced consciousness, reduced senses, reduced bodily activities like breathing or metabolism, reduced muscle activity, and reduced reaction to the surroundings. Simply put, sleep is a temporary state of rest of the mind and the body. 

It is fascinating to know how sleep occurs. The suprachiasmatic nucleus (SCN), in the anterior part of the hypothalamus, is the pacemaker of the body’s circadian rhythm. This is the thing that is commonly referred to as the body clock. SCN sends signals to the pineal gland, releasing a hormone called melatonin that relaxes the body and puts it to sleep.  Many people around the world are troubled with sleep inadequacy which is the poor quality of sleep or complete lack of sleep altogether. Overall, 5-10% of the population of India has inadequate sleep. According to data, in India, 25% of urban children and 35% of children from rural places suffer from sleep deprivation. 

Chronic sleep inadequacy is very common nowadays and is caused by a variety of factors such as workload, responsibilities, existing medical conditions, and sleep disorders. Individuals have detrimental physical and mental effects due to lack of sleep. Sleep is measured in quantity (which is the duration of sleep) and quality (which is the depth of sleep). When individuals fail to obtain adequate quantity or quality of sleep, alertness and normal behaviors suffer. Those suffering from sleep deprivation may often have a long and deep sleep. Sleep intensity and sleep duration are not dependent on each other. Individuals may sleep for long hours and still not feel they slept well while in some cases other individuals take very fulfilling short naps. Therefore, sleep duration or sleep quality cannot be good indicators alone and must be assessed together in all instances.

The need for sleep for different individuals varies for various reasons. While most adults report sleeping six to eight hours per night, some otherwise healthy individuals may sleep for even shorter durations, even less than six hours, without complaining about exertion or exhaustion. While some adults, on the other hand, require about ten hours of sleep for normal day-to-day functioning. Insufficient sleep in the long term has a significant negative impact on health, especially cardiovascular health. 

If not taken care of, one can face severe issues, therefore it is recommended to get a health check done. For this, it helps to look for a top cardiology hospital in Bangalore, which is one of the best cities in India as the city has abundant cardiology experts. Some of the effects of inadequate sleep on the heart are as follows-

  1. Coronary artery disease- Poor sleep is associated with the development of coronary artery disease among healthy middle-aged adults. In a large cross-sectional study that included nearly four thousand adults forty to fifty years of age without a history of cardiovascular or obstructive sleep- apnea, those with the shortest sleep duration of fewer than six hours per night, had increased accumulation of fat and cholesterol in and on the artery, walls as measured by an ultrasound procedure. This condition is called Atherosclerosis. Therefore, sleeplessness is a risk factor for coronary artery disease.
  2. Heart Attack- Insufficient sleep is also a predictor of the development of heart attacks. A study was conducted on nearly five lacs adults aged forty to sixty-nine years. These adults were free of cardiovascular disease at the beginning. In a medical check-up of the cardiovascular profile of the same set of individuals after seven years it was found that those who had the habit of sleeping less than six hours per day were associated with a twenty percent increase in the risk of incident heart attacks. According to the analysis, one additional hour of sleep per night would decrease the risk of heart attack by Twenty percent. 
  3. Hypertension- Insufficient sleep is also a predictor of obesity, high glucose, and high blood pressure. A study was conducted with over one and a half lac individuals. All of them were between the ages of eighteen to twenty. They were non-obese and had no cardiovascular issues at that time. They all had sleep duration of fewer than six hours. In a medical follow-up after eighteen years, it was found that the majority of those individuals were now associated with increased risk for the development of multiple risk factors of obesity, elevated fasting glucose, hypertension, low high-density lipoprotein, high triglycerides levels, and metabolic syndrome. 
  4. Arrhythmia- Insufficient sleep is also a predictor of atrial fibrillation, which is a heart arrhythmia. Heart arrhythmia is the periodic beating of the heart at a pace higher or lower than normal. In a study of over thirty thousand adults undergoing diagnostic polysomnography, a one-hour reduction in sleep was associated with increased odds of atrial fibrillation, independent of their age, sex, physiological state, or even with pre-existence of health condition. Therefore, sleep deprivation or inadequate sleep can be a risk factor for arrhythmia.