Forums » Off duty » Journal club » Metabolic Syndrome reversal by CPAP therapy in OSA Patients
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Metabolic Syndrome reversal by CPAP therapy in OSA Patients
posted at 1/1/2012 8:38 PM GMT
on bmj.com
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Posts: 1464
First: 24/12/2008 Last: 6/5/2012 |
A research among moderate-to-severe obstructive sleep apnea (OSA) patients using a gold standard treatment continuous positive airway pressure (CPAP) for this condition have found that a three month treatment partially revereses metabolic syndrome of these patients. A successful treatment of OSA with CPAP have already found reduction in blood pressure (correction of hypertension), restoration of impaired cerebral blood flow response, reduction in BMI etc. Now this impressive study from All India Institute of Medical Sciences (AIIMS) and Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER) in India reports on metabolic syndrome (their markers). The total 86 patients have completed the study and the intervention of CPAP therapy have been done for three months. A total of 90 individuals have undergone randomization. It is a placebo-controlled, double-blind, randomized, crossover study. The wash-out period for CPAP and sham-CPAP is one month and it has been arbitrarily chosen. The abstract: ======================================== BACKGROUNDObstructive sleep apnea is associated with an increased prevalence of the metabolic syndrome and its components. It is unclear whether treatment of obstructive sleep apnea syndrome with continuous positive airway pressure (CPAP) would modify these outcomes. METHODSIn our double-blind, placebo-controlled trial, we randomly assigned patients with obstructive sleep apnea syndrome to undergo 3 months of therapeutic CPAP followed by 3 months of sham CPAP, or vice versa, with a washout period of 1 month in between. Before and after each intervention, we obtained measurements of anthropometric variables, blood pressure, fasting blood glucose levels, insulin resistance (with the use of homeostasis model assessment), fasting blood lipid profile, glycated hemoglobin levels, carotid intima–media thickness, and visceral fat. The metabolic syndrome was defined according to National Cholesterol Education Program Adult Treatment Panel III criteria, with Asian cutoff values for abdominal obesity. RESULTSA total of 86 patients completed the study, 75 (87%) of whom had the metabolic syndrome. CPAP treatment (vs. sham CPAP) was associated with significant mean decreases in systolic blood pressure (3.9 mm Hg; 95% confidence interval [CI], 1.4 to 6.4; P=0.001), diastolic blood pressure (2.5 mm Hg; 95% CI, 0.9 to 4.1; P<0.001), serum total cholesterol (13.3 mg per deciliter; 95% CI, 5.3 to 21.3; P=0.005), non–high-density lipoprotein cholesterol (13.3 mg per deciliter; 95% CI, 4.8 to 21.8; P=0.009), low-density lipoprotein cholesterol (9.6 mg per deciliter; 95% CI, 2.5 to 16.7; P=0.008), triglycerides (18.7 mg per deciliter; 95% CI, 4.3 to 41.6; P=0.02), and glycated hemoglobin (0.2%; 95% CI, 0.1 to 0.4; P=0.003). The frequency of the metabolic syndrome was reduced after CPAP therapy (reversal found in 11 of 86 patients [13%] undergoing CPAP therapy vs. 1 of 86 [1%] undergoing sham CPAP). Accelerated hypertension developed 1 patient receiving CPAP therapy first, intolerance to CPAP developed in 2 others, and another patient declined to continue sham CPAP. CONCLUSIONSIn patients with moderate-to-severe obstructive sleep apnea syndrome, 3 months of CPAP therapy lowers blood pressure and partially reverses metabolic abnormalities. (Funded by Pfizer; ClinicalTrials.gov number, NCT00694616.) ======================================== This is well designed and nicelly carried out study. Looking into relevant aspects of OSA patients i.e metabolic syndrome is clincally relevant. Good research question. It is fairly common problem and it is in increasing trend. I would say three months may be little less period of intervention but the results are not doubted. We could see effect of CPAP in three months, I believe. Thanks. |
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Re: Metabolic Syndrome reversal by CPAP therapy in OSA Patients
posted at 1/1/2012 9:34 PM GMT
on bmj.com
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Posts: 2072
First: 10/3/2009 Last: 16/5/2012 |
This is not surprising, Matiram. However as I have not read the whole paper , I am interested to know the following; COMMENTS
1. How does one do sham CPAP in patients with mod-severe OSA? Many don't even like the real thing. Most patients could tell the difference I think. 2.Was there weight loss during this 3 month period? More info needed here. How was it achieved if at all? 3.Were they being looked after by sleep physicians, sleep technicians, sleep nurses etc. The mere fact of having these patients intensively monitored is an another variable. 4.I am surprised that such compliance occurred. What was the original recruitment sample size. Was it that those who entered and completed the study were just more compliant, more likely to eg lose weight etc compared to the average beer drinking, pot-bellied, shorts and singlet, unshaven middle-aged male fork-lift driver with rip-roaring sleep apnoea? PRACTITIONER INPUT It would be very interesting to see if the results with regards Syndrome X was any better with medical practitioners (sleep docs) supervising CPAP compared to sleep trained nurses. THE RUNNING IN PERIOD The first three months of CPAP sees a significant number of drop outs. Many just don't like it and are unmotivated to use it. I have seen many whose blood pressure control has been made much easier with CPAP. Weight loss is the elephant in the room that disappointingly few address. I am now seeing people with BMI of 50-60 which a few years ago was rare. I have chairs in my rooms with no arms. HOME POLYSOMNOGRAPHY I wonder how many on this site us home studies in selected patients. This is transforming access to polysomnography in Australia, particularly for country patients and those who can't access long public waiting lists or have private health insurance to access private labs. I have so far reported on approximately 5,000 home sleep studies state wide, and with a surface area of 1.7 million square kilometers. An article I wrote on this should be out this year in Australian Prescriber. This problem is just enormous. Over the Christmas Holidays I often wonder how many lives I have saved on the roads by instituting CPAP on some of my worse patients and particularly those with Epworth Sleepiness Scores in the 20's eg 22/24. |
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Re: Metabolic Syndrome reversal by CPAP therapy in OSA Patients
posted at 1/1/2012 10:06 PM GMT
on bmj.com
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Posts: 1317
First: 7/3/2009 Last: 15/5/2012 |
A most interesting subject and really important to be studied further. I would also ask the reverse question: How many people with metabolic syndrome have OSA, and also how many with essential hypertension(not qualifying to be metabolic syndrome) have OSA? Perhaps polysomnography should be a screening procedure for OSA in any of these groups? Might it be that some patients "resistant" to medications could be so due to undiagnosed severe OSA?
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Re: Metabolic Syndrome reversal by CPAP therapy in OSA Patients
posted at 1/1/2012 11:37 PM GMT
on bmj.com
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Posts: 2072
First: 10/3/2009 Last: 16/5/2012 |
I totally agree, Yoram. What's more, I see a lot of patients who are treated for depression for years where OSA is the underlying cause. it is a scotoma for many GPs and psychiatrists. Another myth is that OSA is restricted to fat middle aged men. You can be young, female and beautiful and have OSA. Most of these have an narrow upper airways, eg Malampatti Class 4 throat or a malocclusion. However few really beautiful women have the latter; more wide anterior arches..the big teethy smile.
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Re: Metabolic Syndrome reversal by CPAP therapy in OSA Patients
posted at 2/1/2012 9:40 PM GMT
on bmj.com
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Posts: 1317
First: 7/3/2009 Last: 15/5/2012 |
Perhaps home polysomnography which does not reqire to sleep over at lab can be a tool to check the questions about the true prevalence of OSA in general population and speciically in metabolic syndrome and/or essential hypertension. Right now I believe we seriously underestimate the problem and this might be another "silent killer" together with hypertension and hyperlipidemia.
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Re: Metabolic Syndrome reversal by CPAP therapy in OSA Patients
posted at 8/1/2012 5:17 AM GMT
on bmj.com
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Posts: 1464
First: 24/12/2008 Last: 6/5/2012 |
Thanks Odysseus, I agree with CPAP not being tolerated by all. It is good point that OSA is not only the disease of middle aged obese ones. This is interesting topic ...not only OSA but also sleep in totality. I am sure there will be further papers coming out in coming years. I hope you found those points in the paper OR they might not be there as well @Odysseus.....
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Re: Metabolic Syndrome reversal by CPAP therapy in OSA Patients
posted at 8/1/2012 10:44 AM GMT
on bmj.com
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Posts: 2072
First: 10/3/2009 Last: 16/5/2012 |
Thanks for the papers. I posted a reply about them but it crashed. I was using 3G and my iPad but am now using my laptop. In essence, there was weight loss in the CPAP group which was very compliant probably as the patients were paid (not said as usual). I find what is not said as important as what is said. Although they used an Australian ResMed auto pump there was no mention of what settings and how they applied the data from the PSG CPAP titration. The average use was five hours which I find just passes. I imagine the input given to the CPAP patients may have been more eg more time needed and more fussing but this is never said in papers. Science is still a bit like playing a piece at a concert. It may sound OK superficially but what goes on behind the scenes is just as important. There may even be a dubbed recording so it may not be as it seems and the musician may be miming and the music teacher playing behind the curtain. I know to some this may sound like I am a cynic, but the answer is I am. So was Diogenes.
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Re: Metabolic Syndrome reversal by CPAP therapy in OSA Patients
posted at 8/1/2012 10:51 AM GMT
on bmj.com
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Posts: 2072
First: 10/3/2009 Last: 16/5/2012 |
PS. I was very touched Matiram, that you went to the trouble of sending me the whole papers with attachments, the latter being essential. Here I was on holiday and stuff comes from Canada in the blink of en eye.
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Re: Metabolic Syndrome reversal by CPAP therapy in OSA Patients
posted at 8/1/2012 1:59 PM GMT
on bmj.com
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Posts: 366
First: 13/4/2011 Last: 16/5/2012 |
I have read this NEJM article, perhaps not in such detailed way as both of you, specially Odysseus. I also think seriously about the showed and not-showed details...... As a whole, in my humble opinion, this article delivers only very preliminary observations. And, I did not become enthusiastic with its results. All Best, Joey
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Forums » Off duty » Journal club » Metabolic Syndrome reversal by CPAP therapy in OSA Patients
