Showing posts with label SLEEP. Show all posts
Showing posts with label SLEEP. Show all posts

Sleep Apnea May Increase Risk Of Patients With Type 2 Diabetes Developing Advanced Retinopathy, Study Suggests

By Dr Deepu

A study has revealed that patients with sleep apnea who also have type 2 diabetes “have more than double the risk of worsening retina disease compared to diabetics without the sleep breathing disorder,”. The study was published in the American Journal of Respiratory and Critical Care Medicine. Researchers found that 43% of the study participants who had type 2 diabetes and sleep apnea had diabetic retinopathy, compared to 24% of participants who had type 2 diabetes without sleep apnea.

Sleep Apnea May Impact Brain Function, mood and Skills

By Dr Deepu

HealthDay (2/29, Dallas) reports that a study published in the Journal of Sleep Research suggests that “sleep apnea may have an impact on brain function.” Investigators “examined levels of two brain chemicals: glutamate and gamma-aminobutyric acid, also known as GABA.” The research indicated that individuals “with sleep apnea have lower levels of GABA and abnormally high levels of glutamate.”

Statins May Reduce Heart Risks Associated With Sleep Apnea, Study Suggests

By Dr Deepu

The NPR (1/7, Chen) “Shots” blog reports that a study (1/7) published in Science Translational Medicine “suggests that cholesterol...plays a special role in raising risk for people with sleep apnea.” The research also “hint[s] that...statins could limit the damage sleep apnea does to blood vessels.” Investigators thought “there might be something happening to the cells lining our blood vessels since they would be the first to experience the particular rise and fall in oxygen afflicting sleep apnea patients.”
        STAT (1/7, Boodman) reports that the investigators “extracted these cells from the arms of 76 patients with obstructive sleep apnea and 52 others who” did not have OSA. Sleep apnea patients were found to have higher CD59 levels. The researchers found that “the CD59 of people with sleep apnea had been pulled inside the cell, instead of guarding the cell’s surface, leaving the cell vulnerable to attacks from the immune system.” The “damaged cells, in turn, would be more likely to obstruct blood flow – the first such cellular explanation of how apnea may cause heart problems.” The investigators found, however, that patients with OSA who were taking statins did not exhibit “these abnormal CD59 effects.”
        HealthDay (1/7, Haelle) reports, “How much protein the cells pulled inside them depended on how much cholesterol...was present.” The researchers found that “statins stopped the cells from bringing the protein inside them.”

Obstructive sleep apnea is a common medical condition characterized by intermittent cessation of breathing during sleep, which results in intermittent hypoxia. It greatly increases patients’ risk of cardiovascular disease, and now Emin et al. provide a mechanism, which helps to explain this correlation. The authors discovered that intermittent hypoxia causes internalization of CD59, a protein that is normally found on the membrane of endothelial cells and protects them from being injured by circulating complement. After internalization, CD59 could no longer protect the cells, resulting in damage to the vascular walls. In contrast, statins stabilized CD59 on the endothelial cell surface and protected them from injury, revealing yet another mechanism by which these versatile drugs protect against cardiovascular disease.

Sleep-Disordered Breathing In Kids May Be Linked To Academic Problems

By Dr Deepu

HealthDay (9/9) reports that research suggests that “when children have sleep troubles due to breathing problems – such as sleep apnea – they may struggle in school.” Investigators “reviewed the results of 16 studies dealing with sleep apnea or related disorders in children and academic achievement.” The data indicated that kids “with sleep-disordered breathing did worse in language arts, math and science tests compared to those without such conditions.” The findings were published online in Pediatrics.
The researchers reviewed the results of 16 studies dealing with sleep apnea or related disorders in children and academic achievement. The investigators found that children with sleep-disordered breathing did worse in language arts, math and science tests compared to those without such conditions.

Two Clinical Trials Indicate Tasimelteon May Help Establish Normal Sleep Rhythms For The Blind

By Dr Deepu
Reuters (8/12, Rapaport) reports that Vanda Pharmaceuticals Inc. announced that two clinical tests for Hetlioz (tasimelteon) showed that the drug helped blind patients achieve normal sleep rhythms. Last year, Hetlioz was approved by the Food and Drug Administration with orphan drug status, which allowed it to receive approval based upon smaller trials. The two studies examined 104 totally blind patients throughout 27 clinical trial centers in the US and Europe.

Companies Work To Help Employees With Insomnia

By Dr Deepu

The Washington Post (7/31, McGregor) reports research from Harvard is showing that “insomnia results in the loss of 11.3 days of productivity each year” for the average worker and represents a total national loss of $63.2 billion. As a result of the “impact on insurance costs and worker productivity,” some companies have implemented means to help their employees get better sleep.

Sleep Apnea May Lead To Development, Attention Problems In Kids

By Dr Deepu
The New York Times (7/27) “Well” blog reports that “experts say that between 1 percent and 3 percent of children have sleep apnea that, if untreated, can disrupt far more than a family’s restful nights.” Children with the condition “simply do not get enough restorative sleep to assure normal development.” Sleep apnea, “if not corrected...can result in hyperactivity and attention problems in school that are often mistaken for attention deficit hyperactivity disorder.”


1.     Syndrome in which repetitive episodes of cessation of airflow or decreases in airflow occur during sleep in the presence of continued respiratory effort (obstructive sleep apnea). Cessation of airflow without respiratory effort is seen in central sleep apnea. A combination of these two events is seen in mixed apneas.
2.     The Apnea/Hypopnea Index (AHI) is a method of quantifying the severity of the sleep disordered breathing. It is the sum of all respiratory events occurring over a full night divided by the total sleep time recorded in hours. An AHI>5/hour is considered abnormal in most populations, and in the appropriate clinical setting, defines obstructive sleep apnea syndrome (OSAS).
3.     Recent studies have found an incidence of OSAS of approximately 4% in middle aged US males, and approximately 2% of females. Children and infants may also be afflicted. Familial clustering has been reported.
4.     Risk factors for OSAS:
o    obesity
o    advancing age
o    snoring
o    sleep deprivation
o    ethanol and sedative/hypnotic medications
o    hypothyroidism
o    general anesthetics
o    certain antihypertensive agents (methyldopa, propranolol)
o    COPD
o    ribcage and neuromuscular abnormalities
o    CNS disorders
o    nasal obstruction
o    tonsillar/adenoidal hypertrophy
o    acromegaly
o    micro and retrognathia
o    macroglossia
o    lymphoma
o    Shy-drager Syndrome
o    amyloidosis
o    congenital syndromes
Signs and Symptoms
1.     manifestations of above mentioned risk factors
2.     excessive daytime somnolence
3.     sleep maintenance problems
4.     abnormal motor activity during sleep
5.     abnormal sleep positions
6.     parasomnias
7.     signs differ in children:
o    hyperactivity
o    irritability
o    developmental delays
o    growth retardation
Pathophysiology of Obstructive Apneas
1.     Initial pharyngeal obstruction:
o    Usually occurs at level of velopharynx, may also occur in hypopharynx
o    Pharyngeal dilator muscle hypotonia, especially during REM sleep
o    Compromised anatomy of upper airway
2.     Consequences of occlusion
o    Hypoxemia
o    Hypercapnia
o    Arousal
3.     Post-apneic Ventilation
Complications of OSAS
  • cardiac arrhythmias and conduction disturbances
    • sinus arrhythmia
    • second degree or complete AV Block
    • prolonged sinus pauses
    • paroxysmal atrial fibrillation
    • ventricular tachycardia
  • systemic and pulmonary hypertension
    • SBP > 200mm Hg at conclusion of obstructive events
    • decreased MAP during events
    • increased ischemic events (associated with BP changes and gas exchange abnormalities)
    • PCWP increases (may cause pulmonary edema)
  • long term consequences
    • pulmonary hypertension
    • cor pulmonale
    • systemic hypertension
    • increased vascular mortality/death
  • excessive daytime somnolence
  • personality changes
  • cognitive dysfunction and memory impairment
  • impotence
  • depression
  • loss of productivity
  • increased motor vehicle accidents (7-fold increase over non-apneic controls)
Diagnostic Evaluation of Patients with Suspected OSAS
1.     History
o    typical sleep-wake cycle
o    quality of sleep
o    medication ingestion
o    habits (tobacco, caffeine, alcohol)
o    stressors
o    exercise
o    sleep environment
o    associated symptoms (morning headache, dry mouth, snoring)
o    family history of sleep disorders
2.     Physical Examination
o    HEENT
o    Hypertension
o    body habitus
o    neck size
o    cardiac exam
o    mental status
o    thyroid abnormalities
o    neuropathy
3.     Sleep Questionnaire and Diary
4.     Nocturnal Polysomnography
o    ambulatory vs. laboratory
o    AHI
o    arousal index
o    desaturations
o    arrhythmias
1.     Weight Reduction
2.     Positional Treatment
3.     Correct increased nasal resistance
4.     Dental Appliances
5.     Increase Upper Airway Muscle Tone
o    avoid alcohol, sedatives and hypnotics
o    pharmacologic intervention
o    protriptyline
o    progesterone
o    theophylline
o    strychnine/nicotine
o    electrical stimulation
6.     Nasal Continuous Positive Airway Pressure
o    standard of care
o    titrated pressure
o    nasal mask vs. pillows
o    CPAP vs. BiPAP
o    "AutoPAP" or DPAP or VPAP
o    Compliance
7.     Surgical Correction of Upper Airway Anatomic Abnormalities
o    tracheostomy

o    nasal surgery



1.Clinical  guidelines for evaluation, management and long term care of obstructive sleep apnead in adults – American association of sleep medicine