Sleeping habits - how they affect functioning of Heart

What is the effect of lack of sleep on heart?

• Increased risk of Diabetes, high blood pressure and heart diseases
• Decrease in anti oxidant levels ( which prevents our body from oxidative damage)
• Increase in endothelin ( hormone which increases blood pressure)
• Glucose intolerance
• Endothelial dysfunction
• OBESITY

To be able to attempt to find a reason to above factors, let us learn more about our sleep.

• Why is sleep important?
  
• What are different stages of sleep?
• What is healthy sleep?
• What are sleep disorders?
• What is sleep cycle?

Some FACTS:

• Sleep comprises upto one third of our lifetime.
• Sleep affects the coagulative property of blood.
• Sleep helps to keep blood vessels healthy.

Stages of Sleep

There are two phases in our sleep, with multiple occurrences:

1. REM sleep (Rapid eye movement)

In this phase the nervous system of your body acts in a very erratic way and
the neural drive is highly erratic. There is increase in blood pressure, increase in heart rate and increased chances of electrical disturbances to occur in heart of susceptible patients.

This phase is akin to a roller-coastal ride.

2. NREM (non rapid eye movement) sleep.

This is a peaceful phase with normal stable heart and nervous system function.

Healthy Sleep

Generally speaking in one night's healthy sleep, 25% is REM phase and remaining 75% is NREM phase.
There is evidence that more your are mentally disturbed, the longer is the REM phase duration. You wake up feeling tired and with a heavy head in such cases.

Sleep Disorders

Sleeping disorders are broadly categorized into 2 types:

1. Breathing disorders

These are further divided into:

• OSA-Obstructive sleep apnea (apnea means cessation of breathing efforts)
• CSA- Central sleep apnea

Signs and symptoms:

• Disruptive snoring
• Witnessed gasping for breath during sleep
• Obesity and or enlarged neck size
• Sleepiness during day
• Morning headache
• Sexual dysfunction
• Behavioral changes in children

Let's talk about OSA.

OSA causes reduced oxygen saturation the blood. This causes compression of the pulmonary artery. It is a large artery which supplies impure blood from heart to lungs for purification. This constriction causes reduced blood supply to lungs.


Some FACTS:

20% of middle aged western adults with BMI of 25-28 have OSA
more than 85% of these cases are undiagnosed –iceberg phenomenon

50% OSA patients are hypertensive and 30% hypertensive patients have OSA
In drug resistant hypertension, prevalence of OSA is a whopping 83%

"Logan etal High prevalence of unrecognized sleep apnoea in drug-resistant hypertension.J Hypertens. 2001;19"

Cardiovascular diseases and OSA

• Increased blood pressure
• Heart failure
• Stroke
• Arrhythmias (electric disturbances in heart)
• Heart attack
• Pulmonary arterial hypertension ( increased blood pressure in artery to lungs)

Diagnosis is by sleep studies called as Polysomnography

Treatment options:

• Positional therapy
• Weight loss
• Avoidance of alcohol and sedatives before sleep
• CPAP (specialized ventilator for this disease)
• Oral appliances
• Surgery – removal of tonsils or other enlarged glands in neck.

Let's talk about CSA.

Some FACTS:

• Associated with Aging,heart failure and stroke
• 5% prevalence in males older than 65 yrs of age

Definition:
More than 5 central apnea episodes (>10 sec pause in ventilation with no associated respiratory effort) per hour of sleep and associated symptoms of disrupted sleep (frequent arousals) and /increased sleep during the day.

Diagnosis:

• Overnight oxymetry
• Ambulatory polysomnography (sleep studies)
• In hospital polysomnography (sleep studies)

Treatment:

• CPAP ( specialized ventilator)
• Optimize treatment of heart failure
• Supplemental oxygen therapy

2. Insomnia (Inability to fall asleep)

This is probably the commonest complaint. Everybody experiences transient phases of insomnia.
Whenever you are tensed, nervous, worried, insecure you are unable to sleep. This is normal body response. But some times it happens in a fashion similar to a disease. There are so many people who require sleeping pills.

Q. Are these pills harmful?

Ans. Yes every medication has side effects, more over continuous use of these sleeping pills makes body adapted for their use, and a sense of craving starts for them, in a way that you would require increasing doses of these pills.

Q. How to get rid of these sleeping pills?

Ans. It is possible to a great extent to get out of the habit of taking these pills. Try the following:

• Maintain sleep hygiene.
• Make a strict time table for going to bed and waking up.
• Avoid coffee, tea and alcohol in evening
• Do some reading before sleep
• Avoid television prior to sleep time
• Avoid heavy meals in night.
• Go to bed on fix time each day and wake up on a fix time. Do not worry if you are not able to sleep, because regularization of sleep cycle will take some time.
• Keep lights dim in bed room, no noise
• Avoid day time sleeping. This is probably the most neglected part of sleep hygiene. If you are not able to sleep properly in night, then you try to oversleep in day time and again in night you feel difficulty in falling sleep.
• Yoga and meditation could help you to achieve mental relaxation.
• Exercise daily.
• Early to bed early to rise keeps you healthy wealthy and wise!!!