Today is WORLD CANCER DAY.
Yesterday I prepared you for this event by alerting you to a disgusting cancer scam, and today I want to contrast this with more encouraging news from the strange world of alternative medicine. So I searched Medline for a fitting, recent publication showing at least some value of an alternative therapy. Believe me, such papers are few and far between.
But here is one:
The aim of this Cochrane review was to assess effects of yoga on health-related quality of life, mental health and cancer-related symptoms among women with a diagnosis of breast cancer who are receiving active treatment or have completed treatment. The authors conducted extensive literature searches and applied no language restrictions. RCTs were eligible, if they (1) compared yoga interventions to no therapy or to any other active therapy in women with a diagnosis of breast cancer, and (2) assessed at least one of the primary outcomes on patient-reported instruments, including health-related quality of life, depression, anxiety, fatigue or sleep disturbances.
Two review authors independently collected data on methods and results. The risk of publication bias was assessed through visual analysis of funnel plot symmetry and heterogeneity between studies. Subgroup analyses were conducted for current treatment status, time since diagnosis, stage of cancer and type of yoga intervention.
Twenty-four studies with a total of 2166 participants were included, 23 of which provided data for meta-analysis. Thirteen studies had low risk of selection bias, five studies reported adequate blinding of outcome assessment and 15 studies had low risk of attrition bias. Seventeen studies that compared yoga versus no therapy provided moderate-quality evidence showing that yoga improved health-related quality of life, reduced fatigue and reduced sleep disturbances in the short term. There was an overall low risk of publication bias.
Yoga did not appear to reduce depression or anxiety in the short term and had no medium-term effects on health-related quality of life or fatigue. Four studies that compared yoga versus psychosocial/educational interventions provided moderate-quality evidence indicating that yoga can reduce depression, anxiety and fatigue in the short term. Very low-quality evidence showed no short-term effects on health-related quality of life or sleep disturbances. Three studies that compared yoga to exercise presented very low-quality evidence showing no short-term effects on health-related quality of life or fatigue. No trial provided safety-related data.
The authors concluded that moderate-quality evidence supports the recommendation of yoga as a supportive intervention for improving health-related quality of life and reducing fatigue and sleep disturbances when compared with no therapy, as well as for reducing depression, anxiety and fatigue, when compared with psychosocial/educational interventions. Very low-quality evidence suggests that yoga might be as effective as other exercise interventions and might be used as an alternative to other exercise programmes.
As I said, this is most encouraging. Many women are attracted by yoga, and the news that it can improve their symptoms is clearly positive. I have said it often, but I say it again: in supportive and palliative cancer care there might be an important role for several forms of CAM. One has to make sure though that they do not interfere with conventional treatments, and – this is very important – cancer patients must not be misled to believe that they can be used to treat or cure cancer. Finally, patients should not pitch their hopes too high: the effect sizes of alternative treatments in cancer care are invariably small or modest which means that they can help to reduce symptoms but are unlikely to get rid of them completely.
On an even more sober note, I have to reiterate that none of the trials included in the above review reported safety data (yoga is not totally devoid of adverse-effects!). This is an almost stereotypical finding when assessing clinical trials of alternative therapies. It discloses a clear and unacceptable breach of publication ethics. How can we ever get a realistic impression of the risks of alternative medicine, if adverse effects remain unreported? It is high time that researchers, authors, journal editors and reviewers get this message and behave accordingly.
WARNING: THIS MIGHT MAKE YOU LAUGH OUT LOUDLY AND UNCONTROLLABLY.
Deepak Chopra rarely publishes in medical journals (I suppose, he has better things to do). I was therefore intrigued when I saw a recent article of which he is a co-author.
The ‘study‘ in question allegedly examined the effects of a comprehensive residential mind–body program on well-being. The authors describe it as “a quasi-randomized trial comparing the effects of participation in a 6-day Ayurvedic system of medicine-based comprehensive residential program with a 6-day residential vacation at the same retreat location.” They included 69 healthy women and men who received the Ayurvedic intervention addressing physical and emotional well-being through group meditation and yoga, massage, diet, adaptogenic herbs, lectures, and journaling. Key components of the program include physical cleansing through ingestion of herbs, fiber, and oils that support the body’s natural detoxification pathways and facilitate healthy elimination; two Ayurvedic meals daily (breakfast and lunch) that provide a light plant-based diet; daily Ayurvedic oil massage treatments; and heating treatments through the use of sauna and/or steam. The program includes lectures on Ayurvedic principles and lifestyle as well as lectures on meditation and yoga philosophy. The study group also participated in twice-daily group meditation and daily yoga and practiced breathing exercises (pranayama) as well as emotional expression through a process of journaling and emotional support. During the program, participants received a 1-hour integrative medical consultation with a physician and follow-up with an Ayurvedic health educator.
The control group simply had a vacation without any of the above therapies in the same resort. They were asked to do what they would normally do on a resort vacation with the additional following restrictions: they were asked not to engage in more exercise than they would in their normal lifestyle and to refrain from using La Costa Resort spa services. They were also asked not to drink ginger tea or take Gingko biloba during the 2 days before and during the study week.
Recruitment was via email announcements on the University of California San Diego faculty and staff and Chopra Center for Wellbeing list-servers. Study flyers stated that the week-long Self-Directed Biological Transformation Initiative (SBTI) study would be conducted at the Chopra Center for Wellbeing, located at the La Costa Resort in Carlsbad, California, in order to learn more about the psychosocial and physiologic effects of the 6-day Perfect Health (PH) Program compared with a 6-day stay at the La Costa Resort. The study participants were not blinded, and site investigators and study personnel knew to which group participants were assigned.
Participants in the Ayurvedic program showed significant and sustained increases in ratings of spirituality and gratitude compared with the vacation group, which showed no change. The Ayurvedic participants also showed increased ratings for self-compassion as well as less anxiety at the 1-month follow-up.
The authors arrived at the following conclusion: Findings suggest that a short-term intensive program providing holistic instruction and experience in mind–body healing practices can lead to significant and sustained increases in perceived well-being and that relaxation alone is not enough to improve certain aspects of well-being.
This ‘study’ had ethical approval from the University of California San Diego and was supported by the Fred Foundation, the MCJ Amelior Foundation, the National Philanthropic Trust, the Walton Family Foundation, and the Chopra Foundation. The paper’s first author is director of research at the Chopra Foundation. Deepak Chopra is the co-founder of The Chopra Center for Wellbeing.
Did I promise too much?
Isn’t this paper hilarious?
Just for the record, let me formulate a short conclusion that actually fits the data from this ‘study’: Lots of TLC, attention and empathy does make some people feel better.
This is hardly something one needs to write home about; and certainly nothing to do a study on!
But which journal would publish such unadulterated advertising?
On this blog, I have mentioned the JACM several times before. Recently, I wrote about the new man in charge of it. I concluded stating WATCH THIS SPACE.
I think the wait is now over – this paper is from the latest issue of the JACM, and I am sure we all agree that the new editor has just shown us of what he is made and where he wants to take his journal.
Just as I thought that this cannot get any better, it did! It did so in the form of a second paper which is evidently reporting from the same ‘study’. Here is its abstract unaltered in its full beauty:
The effects of integrative medicine practices such as meditation and Ayurveda on human physiology are not fully understood. The aim of this study was to identify altered metabolomic profiles following an Ayurveda-based intervention. In the experimental group, 65 healthy male and female subjects participated in a 6-day Panchakarma-based Ayurvedic intervention which included herbs, vegetarian diet, meditation, yoga, and massage. A set of 12 plasma phosphatidylcholines decreased (adjusted p < 0.01) post-intervention in the experimental (n = 65) compared to control group (n = 54) after Bonferroni correction for multiple testing; within these compounds, the phosphatidylcholine with the greatest decrease in abundance was PC ae C36:4 (delta = -0.34). Application of a 10% FDR revealed an additional 57 metabolites that were differentially abundant between groups. Pathway analysis suggests that the intervention results in changes in metabolites across many pathways such as phospholipid biosynthesis, choline metabolism, and lipoprotein metabolism. The observed plasma metabolomic alterations may reflect a Panchakarma-induced modulation of metabotypes. Panchakarma promoted statistically significant changes in plasma levels of phosphatidylcholines, sphingomyelins and others in just 6 days. Forthcoming studies that integrate metabolomics with genomic, microbiome and physiological parameters may facilitate a broader systems-level understanding and mechanistic insights into these integrative practices that are employed to promote health and well-being.
Now that I managed to stop laughing about the first paper, I am not just amused but also puzzled by the amount of contradictions the second article seems to cause. Were there 65 or 69 individuals in the experimental group? Was the study randomised, quasi-randomised or not randomised? All of these versions are implied at different parts of the articles. It turns out that they randomised some patients, while allocating others without randomisation – and this clearly means the study was NOT randomised. Was the aim of the study ‘to identify altered metabolomic profiles following an Ayurveda-based intervention’ or ‘to examine the effects of a comprehensive residential mind–body program on well-being’?
I am sure that others will find further contradictions and implausibilites, if they look hard enough.
The funniest inconsistency, in my opinion, is that Deepak Chopra does not even seem to be sure to which university department he belongs. Is it the ‘Department of Family Medicine and Public Health, University of California, San Diego, La Jolla, CA.’ as indicated in the 1st paper or is it the ‘Department of Family and Preventive Medicine, University of California San Diego, La Jolla, California, USA’ as listed in the 2nd article?
Does he know from which planet he is?
In alternative medicine, good evidence is like gold dust and good evidence showing that alternative therapies are efficacious is even rarer. Therefore, I was delighted to come across a brand-new article from an institution that should stand for reliable information: the NIH, no less.
According to its authors, this new article “examines the clinical trial evidence for the efficacy and safety of several specific approaches—acupuncture, manipulation, massage therapy, relaxation techniques including meditation, selected natural product supplements (chondroitin, glucosamine, methylsulfonylmethane, S-adenosylmethionine), tai chi, and yoga—as used to manage chronic pain and related disability associated with back pain, fibromyalgia, osteoarthritis, neck pain, and severe headaches or migraines.”
The results of this huge undertaking are complex, of course, but in a nutshell they are at least partly positive for alternative medicine. Specifically, the authors state that “based on a preponderance of positive trials vs negative trials, current evidence suggests that the following complementary approaches may help some patients manage their painful health conditions: acupuncture and yoga for back pain; acupuncture and tai chi for OA of the knee; massage therapy for neck pain with adequate doses and for short-term benefit; and relaxation techniques for severe headaches and migraine. Weaker evidence suggests that massage therapy, SM, and osteopathic manipulation might also be of some benefit to those with back pain, and relaxation approaches and tai chi might help those with fibromyalgia.”
This is excellent news! Finally, we have data from an authoritative source showing that some alternative treatments can be recommended for common pain conditions.
Hold on, not so fast! Yes, the NIH is a most respectable organisation, but we must not blindly accept anything of importance just because it appears to come form a reputable source. Let’s look a bit closer at the actual evidence provided by the authors of this paper.
Reading the article carefully, it is impossible not to get troubled. Here are a few points that concern me most:
- the safety of a therapy cannot be evaluated on the basis of data from RCTs (particularly as it has been shown repeatedly that trials of alternative therapies often fail to report adverse effects); much larger samples are needed for that; any statements about safety in the aims of the paper are therefore misplaced;
- the authors talk about efficacy but seem to mean effectiveness;
- the authors only included RCTs from the US which must result in a skewed and incomplete picture;
- the article is from the National Center for Complementary and Integrative Health which is part of the NIH but which has been criticised repeatedly for being biased in favour of alternative medicine;
- not all of the authors seem to be NIH staff, and I cannot find a declaration of conflicts of interest;
- the discussion of the paper totally lacks any critical thinking;
- there is no assessment of the quality of the trials included in this review.
My last point is by far the most important. A summary of this nature that fails to take into account the numerous limitations of the primary data is, I think, as good as worthless. As I know most of the RCTs included in the analyses, I predict that the overall picture generated by this review would have changed substantially, if the risks of bias in the primary studies had been accounted for.
Personally, I find it lamentable that such a potentially worthy exercise ended up employing such lousy methodology. Perhaps even more lamentable is the fact that the NIH (or one of its Centers) can descend that low; to mislead the public in this way borders on scientific misconduct and is, in my view, unethical and unacceptable.
Yes, I know, lately I have been neglecting my ‘ALT MED HALL OF FAME’. This is entirely my fault; there are so many candidates waiting to be admitted that, I have been hesitant as to who should be next. Today, I came across an article about Deepak Chopra and his latest book, Super Genes. It tells “how lifestyle shifts can help you reboot your health at a genetic level.” If it were just for this single sentence, he would deserve to be admitted – no, not into what you just thought, into the ‘ALT MED HALL OF FAME’, of course’.
I will save you the expense of buying his book (don’t worry, Deepak is already a multi-millionaire) by repeating what the article said about his ‘6 pillars of wellbeing’ (another cracker!!!):
• A typical modern diet is very likely to cause inflammation, which research has linked to many chronic diseases and obesity.
• To reduce inflammation, add prebiotics – substances that buffer the body from inflammation – such as oatmeal, pulpy orange juice, bran cereal and bananas to your breakfast.
• Consume probiotics – foods that contain active bacteria – once a day for gut health. These foods include active yoghurt, pickles and sauerkraut.
• Eat mindfully – eat only when you’re genuinely hungry and stop when you are full.
• Reduce snacking by eating only one measured portion in a bowl; never eat straight from a bag or packet.
• Three factors generally lie behind the problem of chronic stress: repetition, unpredictability and a lack of control. Think of a dog barking outside your window; you don’t know when it will end and you have no way of stopping it.
• Decrease background noise and distractions at work. Also, avoid multitasking by dealing with one thing at a time.
• Leave work on time at least three times a week and don’t bring work home. Leave the office at the office.
• Avoid people who are sources of pressure and conflict. Even normal office behaviour, such as forming cliques and gossiping, is a source of stress that has the potential to be emotionally devastating.
• If you struggle to deal with negative emotions, ask your doctor about cognitive behaviour therapy.
• The secret to exercise is this: keep going and don’t stop. It’s better to be active all your life at a lower level, rather than to be at a near professional-level in high school, say, and then stop completely.
• At work get up and move around once an hour and devote half your lunch break to movement, even if it’s walking around the block.
• Be in nature more: go outside for five to 10 minutes three times a day.
• Acquire more active friends and join them in their activities. Plan a shared exercise activity with your spouse or friends twice a week.
• Make leisure time more creative – think beyond TV or internet.
• Volunteer to help the needy with housecleaning, painting and repairs.
This will serve as both exercise and a morale boost.
• Meditate every day for 10 minutes.
Sit with your eyes closed in a quiet place, put your attention on the tip of your nose and focus on the sensation of your breath coming in and out of your nostrils.
• Don’t look at meditation as an aid for the bad days you experience (“I’m feeling good today, so I don’t need to meditate”). It should be a lifelong practice.
• Take 10 minutes out of your lunch break to sit alone with eyes closed, preferably outside in nature.
• Notice what a relief it is to take big deep breaths when you are upset or nervous, and how ragged your breath becomes when you are anxious or stressed.
• Join an organised meditation course in your area. Search for meetup.com to find local groups that meet all around the country.
• Make your bedroom as dark as possible. If total darkness is impossible, wear a sleep mask.
• Drink a glass of warm almond milk, which is rich in calcium and promotes melatonin, a hormone that helps to regulate the sleep-wake cycle.
• Experiment with herbal teas associated with good sleep such as chamomile, valerian, passionflower, lavender and kava kava.
• Explore abhyanga, a self-massage technique that uses warmed sesame oil, lightly massaged into arms, legs, neck and torso (go to YouTube to see tutorials).
• Don’t ignore insomnia. In some studies sleep disorders have been associated with triggering Alzheimer’s disease and are also associated with high blood pressure.
• Take responsibility for your feelings. Wellbeing depends upon happiness, yet most people don’t really make that connection.
• Write down five specific things that make you happy and, on a daily basis, do at least one of them.
• Set a “good news policy” at meal times, whether it’s the radio station you choose to listen to or the topic of conversation around the table.
• Explore a time in your past when you were happy and learn from it, whether that means re-embracing an old hobby or getting in touch with an old friend.
• Become comfortable with delayed gratification – consider how your choices will make you feel in the future as well as today.
END OF QUOTE
My favourite website about Deepak Chopra is the one by Tom Williamson. It states that “it has been said by some that the thoughts and tweets of Deepak Chopra are indistinguishable from a set of profound sounding words put together in a random order, particularly the tweets tagged with “#cosmisconciousness”. This site aims to test that claim! Each “quote” is generated from a list of words that can be found in Deepak Chopra’s Twitter stream randomly stuck together in a sentence.” It seems to me that Deepak himself might have made ample use of this site for writing his latest book, and if you should ever run out of platitudes or empty phrases, this site will serve you well.
Deepak has published plenty of best-sellers, but he has as good as nothing to show for himself in the peer-reviewed medical literature. (When you are that famous, you obviously don’t need to bother anymore with trivia such as evidence, science and all that jazz.) This means that I had to deviate from my usual admission criteria for the “prophet of alternative medicine”, as Deepak likes to be called. But he is well worth making an exception, I am sure you agree, he is the absolute super-star!
Super-star of what?
I let you decide!
Yoga is a popular form of alternative medicine. Evidence for its effectiveness is scarce and generally far from convincing. But at least it is safe! At least this is what yoga enthusiasts would claim. Unfortunately, this is not entirely true; adverse events have also been reported with some regularity. Their frequency is, however, not known.
A new study was aimed at filling this gap. It was conducted to elucidate the frequencies and characteristics of adverse events of yoga performed in classes and the risk factors of such events.
The subjects were 2508 people taking yoga classes and 271 yoga therapists conducting the classes. A survey for yoga class attendees was performed on adverse events that occurred during a yoga class on the survey day. A survey for yoga therapists was performed on adverse events that the therapists had observed in their students to date. Adverse events were defined as “undesirable symptoms or responses that occurred during a yoga class”.
Among 2508 yoga class attendees, 1343 (53.5%) had chronic diseases and 1063 (42.3%) were receiving medication at hospitals. There were 687 class attendees (27.8%) who reported some type of undesirable symptoms after taking a yoga class. Musculoskeletal symptoms such as myalgia were the most common symptoms, involving 297 cases, followed by neurological symptoms and respiratory symptoms. Most adverse events (63.8%) were mild and did not interfere with class participation. The risk factors for adverse events were examined, and the odds ratios for adverse events were significantly higher in attendees with chronic disease, poor physical condition on the survey day, or a feeling that the class was physically and mentally stressful. In particular, the occurrence of severe adverse events that interfered with subsequent yoga practice was high among elderly participants (70 years or older) and those with chronic musculoskeletal diseases.
The authors concluded that the results of this large-scale survey demonstrated that approximately 30% of yoga class attendees had experienced some type of adverse event. Although the majority had mild symptoms, the survey results indicated that attendees with chronic diseases were more likely to experience adverse events associated with their disease. Therefore, special attention is necessary when yoga is introduced to patients with stress-related, chronic diseases.
I find these findings interesting and thought-provoking. The main question that they raise is, I think, the flowing: ARE THERE ANY CONDITIONS FOR WHICH YOGA DEMONSTRABLY GENERATES MORE GOOD THAN HARM?
Iyengar Yoga, named after and developed by B. K. S. Iyengar, is a form of Hatha Yoga that has an emphasis on detail, precision and alignment in the performance of posture (asana) and breath control (pranayama). The development of strength, mobility and stability is gained through the asanas.
B.K.S. Iyengar has systematised over 200 classical yoga poses and 14 different types of Pranayama (with variations of many of them) ranging from the basic to advanced. This helps ensure that students progress gradually by moving from simple poses to more complex ones and develop their mind, body and spirit step by step.
Iyengar Yoga often makes use of props, such as belts, blocks, and blankets, as aids in performing asanas (postures). The props enable students to perform the asanas correctly, minimising the risk of injury or strain, and making the postures accessible to both young and old.
Sounds interesting? But does it work?
The objective of this recent systematic review was to conduct a systematic review of the existing research on Iyengar yoga for relieving back and neck pain. The authors conducted extensive literature searches and found 6 RCTs that met the inclusion criteria.
The difference between the groups on the post-intervention pain or functional disability intensity assessment was, in all 6 studies, favouring the yoga group, which projected a decrease in back and neck pain.
The authors concluded that Iyengar yoga is an effective means for both back and neck pain in comparison to control groups. This systematic review found strong evidence for short-term effectiveness, but little evidence for long-term effectiveness of yoga for chronic spine pain in the patient-centered outcomes.
So, if we can trust this evidence (I would not call the evidence ‘strong), we have yet another treatment that might be effective for acute back and neck pain. The trouble, I fear, is not that we have too few such treatments, the trouble seems to be that we have too many of them. They all seem similarly effective, and I cannot help but wonder whether, in fact, they are all similarly ineffective.
Regardless of the answer to this troubling question, I feel the need to re-state what I have written many times before: FOR A CONDITION WITH A MULTITUDE OF ALLEGEDLY EFFECTIVE THERAPIES, IT MIGHT BE BEST TO CHOSE THE ONE THAT IS SAFEST AND CHEAPEST.
If you have diabetes, chances are that you need life-long treatment. Before effective anti-diabetic medications became available, diabetes amounted to a death sentence. Fortunately, these times are long gone.
…unless, of course, you decide to listen to the promises of alternative practitioners many of whom offer a cure for diabetes. Here is just one website of hundreds that does just that. The following is an abbreviated quote where I have changed nothing, not even the numerous spelling mistakes:
Modern medicine has no permanent cure for diabetes but alternative medicines like yoga ,mudra,ayurveda is very useful to control and even cure diabetes.Ayurveda is an alternative medicine to cure diabetes.
Alternative medicine like ayurveda is a best to cure diabetes naturally.
A serious disorder of the glands,of pancreas to be exact,is diabetes,or madhumeha as described in ayurveda.It is one of the most insidious disorders of the metabolism and,if left undiagnosed or untreated,it may lead to rapid emaciation and ultimately death…
Ayurveda medicines to cure diabetes
In ayurveda the following medicines have been recommended for this disease
Shiljita ————————–240 mg
Nyagrodadhi churna ———3 gm
These should be given twice after meals with decoction of arni.
Vasantakusumakara rasa —120 mg
Shudha Shilajit ————–240 mg
Nag Bhasma —————–120 mg
Haldi ————————–500 mg
Amlaki Churna ————-500 mg
Twice daily with powder of rose-apple stones.Twice daily with honey.
Chadraprabha Vati ——– 500 mg
Mudra the alternative treatment to cure diabetes naturally
Mudra is a non medical and no cost treatment to cure diabetes.You can perform mudras at any time or any position.It is an effective way of treatment you can get better result if you practice it regularly .
It goes without saying that none of these treatments would cure diabetes. A Cochrane review concluded that there is insufficient evidence at present to recommend the use of these interventions in routine clinical practice. It also goes without saying that not many patients would fall for the nonsense proclaimed on this or so many other websites. But even just one single patient dying because of some charlatan promising a cure for life-threatening diseases is one patient too many.
Some time ago, the NYT carried an article entitled HOW YOGA CAN WRECK YOUR BODY. While this might be just a trifle alarmist, it seems clear that injuries can occur and do occur more and more – not least because yoga has become so very popular. It seems relevant therefore to ask what the risks truly are. A recent article might be useful in this respect.
The aim of this study was to examine whether a national sample of yoga practitioners would report discontinued use of yoga due to injury from the practice, assess what injuries resulted in discontinued use, determine what injuries were most common and identify injuries requiring medical attention. The authors used a secondary data analysis of a nationally representative sample of 23,393 adults from the United States.
The results indicate that less than 1% of individuals who had ever practiced yoga (n = 2230) reported an injury from yoga that led to discontinued use. Of those reporting injury, less than one-third (n = 4) reported seeking medical attention. The most commonly reported side-effect of yoga was back pain. Approximately, half of those reporting back pain sought medical attention.
The authors concluded that injury due to yoga is an infrequent barrier to continued practice and severe injury due to yoga is rare.
So, yoga is fairly safe but, in rare cases, injuries can occur. If you are interested in preventing such harm, there are some precautions you can take to make sure you do not sustain injuries.
And one last thing: in my experience, many yoga make quite absurd claims – so, if it sounds to be too good to be true, it probably is.
Yoga, it is often claimed, might be a unique method for disease prevention. One website, for instance, states that numerous studies show how yoga can help prevent these diseases: Heart disease, Alzheimer’s, Osteoporosis and Type II Diabetes.
Cardiovascular diseases (CVD) are responsible for more deaths than any other disease category. Preventing CVD is therefore of prime importance. But are the claims made for yoga really true? What does the reliable evidence tell us?
The aim of our systematic review was to determine the effects of yoga on the primary prevention of CVD. Extensive literature searches were performed to identify all RCTs lasting at least three months, involving healthy adults or people at high risk of CVD. Trials examined any type of yoga and the comparison groups received no intervention or minimal interventions. Outcomes of interest were clinical CVD events and major CVD risk factors. Trials that involved multifactorial lifestyle interventions or weight loss programmes were excluded.
We identified 11 RCTs with a total of just 800 participants. Style and duration of yoga differed between trials. About half of all the trial participants were at high risk of CVD. Most of the studies were at risk of performance bias, with inadequate details reported in many of them to judge the risk of selection bias. None of the studies reported cardiovascular mortality, all-cause mortality or non-fatal events, and most studies were small and short-term.
Yoga was found to produce an average reduction in diastolic blood pressure of 2.90 mmHg. The effect that was small but stable on sensitivity analysis. Triglycerides (-0.27 mmol/l) and high-density lipoprotein (HDL) cholesterol (0.08 mmol/l) were also positively affected. However, these findings were based on small, short-term studies at unclear or high risk of bias. There was no clear evidence of an effect on low-density lipoprotein (LDL) cholesterol. Adverse events, occurrence of type 2 diabetes and costs were not reported in any of the included studies. Quality of life was measured in three trials but the results were inconclusive.
Our conclusion: The limited evidence comes from small, short-term, low-quality studies. There is some evidence that yoga has favourable effects on diastolic blood pressure, HDL cholesterol and triglycerides, and uncertain effects on LDL cholesterol. These results should be considered as exploratory and interpreted with caution.
This systematic review thus offers both good and bad news. The good news is that yoga seems to hold some promise in the prevention of CVD. The bad news, however, is diverse:
- We cannot be sure what type of yoga is best; yoga can entail anything from regular exercise, to breathing techniques, to a complete and comprehensive change of life style.
- The effect sizes are far from remarkable.
- The quality of the research tends to be poor.
- Once again, we have to note that, by not reporting on adverse effects, alt med researchers are violating fundamental research ethics.
Many systematic reviews conclude by stating that more and better research is required – in the case of yoga, this platitude might actually be true.
Research is essential for progress, and research in alternative medicine is important for advancing alternative medicine, one would assume. But why then do I often feel that research in this area hinders progress? One of the reasons is, in my view, the continuous drip, drip, drip of misleading conclusions usually drawn from weak studies. I could provide thousands of examples; here is one recently published article chosen at random which seems as good as any other to make the point.
Researchers from the Department of Internal and Integrative Medicine, Faculty of Medicine, University of Duisburg-Essen, Germany set out to investigate associations of regular yoga practice with quality of life and mental health in patients with chronic diseases. Using a case-control study design, 186 patients with chronic diseases who had elected to regularly practice yoga were selected and compared to controls who had chosen to not regularly practice yoga. Patients were matched individually on gender, main diagnosis, education, and age. Patients’ quality of life, mental health, life satisfaction, and health satisfaction were also assessed. The analyses show that patients who regularly practiced yoga had a significantly better general health status, a higher physical functioning, and physical component score on the SF-36 than those who did not.
The authors concluded that practicing yoga under naturalistic conditions seems to be associated with increased physical health but not mental health in chronically diseased patients.
Why do I find these conclusions misleading?
In alternative medicine, we have an irritating abundance of such correlative research. By definition, it does not allow us to make inferences about causation. Most (but by no means all) authors are therefore laudably careful when choosing their terminology. Certainly, the present article does not claim that regular yoga practice has caused increased physical health; it rightly speaks of “associations“. And surely, there is nothing wrong with that – or is there?
Perhaps, I will be accused of nit-picking, but I think the results are presented in a slightly misleading way, and the conclusions are not much better.
Why do the authors claim that patients who regularly practiced yoga had a significantly better general health status, a higher physical functioning, and physical component score on the SF-36 than those who did not than those who did not? I know that the statement is strictly speaking correct, but why do they not write that “patients who had a significantly better general health status, a higher physical functioning, and physical component score on the SF-36 were more likely to practice yoga regularly”? After all, this too is correct! And why does the conclusion not state that better physical health seems to be associated with a greater likelihood of practicing yoga?
The possibility that the association is the other way round deserves serious consideration, in my view. Is it not logical to assume that, if someone is relatively fit and healthy, he/she is more likely to take up yoga (or table-tennis, sky-diving, pole dancing, etc.)?
It’s perhaps not a hugely important point, so I will not dwell on it – but, as the alternative medicine literature is full with such subtly misleading statements, I don’t find it entirely irrelevant either.