Australian scientist finds new causes of obstructive slee

[Johnny1959]

http://news.xinhuanet.com/english/healt ... 907030.htm

[Todzo]

From his research groups page (see: http://www.neura.edu.au/research/themes/eckert-group ):

While continuous positive airway pressure (CPAP) is highly effective in treating sleep apnoea (See: What is obstructive sleep apnoea), approximately 50% of patients are intolerant or non-adherent. Responses to alternative therapies are variable and are currently difficult to predict.


From the papers abstract (see: http://www.atsjournals.org/doi/abs/10.1 ... o8DjEPfu8Y ):

– – – – – – –

Measurements and Main Results: Pathophysiologic traits varied substantially among participants.

36% of patients with OSA had minimal genioglossus muscle responsiveness during sleep

37% had a low arousal threshold

36% had high (respiratory control) loop gain

28% had multiple nonanatomic features.

Although overall the upper airway was more collapsible in patients with OSA (Pcrit, 0.3 [−1.5 to 1.9] vs. −6.2 [−12.4 to −3.6] cm H2O; P <0.01), 19% had a relatively noncollapsible upper airway similar to many of the control subjects (Pcrit, −2 to −5 cm H2O). In these patients, loop gain was almost twice as high as patients with a Pcrit greater than −2 cm H2O (−5.9 [−8.8 to −4.5] vs. −3.2 [−4.8 to −2.4] dimensionless; P = 0.01). A three-point scale for weighting the relative contribution of the traits is proposed. It suggests that nonanatomic features play an important role in 56% of patients with OSA.

– – – – – –

It is interesting how the 50% find CPAP unusable and apparently 56% of patients with OSA have causes of OSA unrelated to the anatomy which CPAP is designed to deal with. While the high respiratory control loop gain I thought was the major factor may only play in some 36% of the cases my instinct that people stop using CPAP because it does not work for them is apparently on the money!

[49er]

It will be interesting to see if any American scientists pick up on this research. I am skeptical but hopefully, I will be proven wrong.

49er

From his research groups page (see: http://www.neura.edu.au/research/themes/eckert-group ):

While continuous positive airway pressure (CPAP) is highly effective in treating sleep apnoea (See: What is obstructive sleep apnoea), approximately 50% of patients are intolerant or non-adherent. Responses to alternative therapies are variable and are currently difficult to predict.


From the papers abstract (see: http://www.atsjournals.org/doi/abs/10.1 ... o8DjEPfu8Y ):

– – – – – – –

Measurements and Main Results: Pathophysiologic traits varied substantially among participants.

36% of patients with OSA had minimal genioglossus muscle responsiveness during sleep

37% had a low arousal threshold

36% had high (respiratory control) loop gain

28% had multiple nonanatomic features.

Although overall the upper airway was more collapsible in patients with OSA (Pcrit, 0.3 [−1.5 to 1.9] vs. −6.2 [−12.4 to −3.6] cm H2O; P <0.01), 19% had a relatively noncollapsible upper airway similar to many of the control subjects (Pcrit, −2 to −5 cm H2O). In these patients, loop gain was almost twice as high as patients with a Pcrit greater than −2 cm H2O (−5.9 [−8.8 to −4.5] vs. −3.2 [−4.8 to −2.4] dimensionless; P = 0.01). A three-point scale for weighting the relative contribution of the traits is proposed. It suggests that nonanatomic features play an important role in 56% of patients with OSA.

– – – – – –

It is interesting how the 50% find CPAP unusable and apparently 56% of patients with OSA have causes of OSA unrelated to the anatomy which CPAP is designed to deal with. While the high respiratory control loop gain I thought was the major factor may only play in some 36% of the cases my instinct that people stop using CPAP because it does not work for them is apparently on the money!

[Todzo]

I think at least one will. I seem to recall Dr. Park being involved in a project which would deal with the "36% of patients with OSA [that] had minimal genioglossus muscle responsiveness during sleep"!

It will be interesting to see if any American scientists pick up on this research. I am skeptical but hopefully, I will be proven wrong.

49er

From his research groups page (see: http://www.neura.edu.au/research/themes/eckert-group ):

While continuous positive airway pressure (CPAP) is highly effective in treating sleep apnoea (See: What is obstructive sleep apnoea), approximately 50% of patients are intolerant or non-adherent. Responses to alternative therapies are variable and are currently difficult to predict.


From the papers abstract (see: http://www.atsjournals.org/doi/abs/10.1 ... o8DjEPfu8Y ):

– – – – – – –

Measurements and Main Results: Pathophysiologic traits varied substantially among participants.

36% of patients with OSA had minimal genioglossus muscle responsiveness during sleep

37% had a low arousal threshold

36% had high (respiratory control) loop gain

28% had multiple nonanatomic features.

Although overall the upper airway was more collapsible in patients with OSA (Pcrit, 0.3 [−1.5 to 1.9] vs. −6.2 [−12.4 to −3.6] cm H2O; P <0.01), 19% had a relatively noncollapsible upper airway similar to many of the control subjects (Pcrit, −2 to −5 cm H2O). In these patients, loop gain was almost twice as high as patients with a Pcrit greater than −2 cm H2O (−5.9 [−8.8 to −4.5] vs. −3.2 [−4.8 to −2.4] dimensionless; P = 0.01). A three-point scale for weighting the relative contribution of the traits is proposed. It suggests that nonanatomic features play an important role in 56% of patients with OSA.

– – – – – –

It is interesting how the 50% find CPAP unusable and apparently 56% of patients with OSA have causes of OSA unrelated to the anatomy which CPAP is designed to deal with. While the high respiratory control loop gain I thought was the major factor may only play in some 36% of the cases my instinct that people stop using CPAP because it does not work for them is apparently on the money!