MD, PhD, MAE, FMedSci, FRSB, FRCP, FRCPEd.

meta-analysis

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NICE helps practitioners and commissioners get the best care to patients, fast, while ensuring value for the taxpayer. Internationally, NICE has a reputation for being reliable and trustworthy. But is that also true for its recommendations regarding the use of acupuncture? NICE currently recommends that patients consider acupuncture as a treatment option for the following conditions:

Confusingly, on a different site, NICE also recommends acupuncture for retinal migraine, a very specific type of migraine that affect normally just one eye with symptoms such as vision loss lasting up to one hour, a blind spot in the vision, headache, blurred vision and seeing flashing lights, zigzag patterns or coloured spots or lines, as well as feeling nauseous or being sick.

I think this perplexing situation merits a look at the evidence. Here I quote the conclusions of recent, good quality, and (where possible) independent reviews:

So, what do we make of this? I think that, on the basis of the evidence:

  • a positive recommendation for all types of chromic pain is not warranted;
  • a positive recommendation for the treatment of TTH is questionable;
  • a positive recommendation for migraine is questionable;
  • a positive recommendation for prostatitis is questionable;
  • a positive recommendation for hiccups is not warranted;
  • a positive recommendation for retinal migraine is not warranted.

But why did NICE issue positive recommendations despite weak or even non-existent evidence?

SEARCH ME!

 

 

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Omega-3 fatty acids (fish oil) supplementation reduces the occurrence of cardiovascular disease (CVD) and CVD-related mortality in patients at high-risk of CVD and in patients with elevated plasma triglyceride level. Yet, some studies have found an increased risk of atrial fibrillation (AF). AF is the most common sustained cardiac arrhythmia worldwide. It is associated with high morbidity and mortality rates and significant public health burden. Previous studies of the effect of omega-3 fatty acids on AF occurrence have reported contradictory results.

This review evaluated the effect of omega-3 fatty acids on the risk of AF. The results suggest that omega-3 fatty acids supplementation is associated with increased AF risk, particularly in trials that used high doses. Therefore, several factors should be considered before prescribing omega-3 fatty acids, including their dose, type, and formulation (fish, dietary fish oil supplements, and purified fatty acids), as well as patient-related factors and atrial mechanical milieu. Because the benefits of omega-3 fatty acids are dose-dependent, the associated AF risk should be balanced against the benefit for CVD. Patients who take omega-3 fatty acids, particularly at high doses, should be informed of the risk of AF and followed up for the possible development of this common and potentially hazardous arrhythmia.

Another recent review included 54,799 participants from 17 cohorts. A total of 7,720 incident cases of AF were ascertained after a median 13.3 years of follow-up. In multivariable analysis, EPA levels were not associated with incident AF, HR per interquintile range (ie, the difference between the 90th and 10th percentiles) was 1.00 (95% CI: 0.95-1.05). HRs for higher levels of DPA, DHA, and EPA+DHA, were 0.89 (95% CI: 0.83-0.95), 0.90 (95% CI: 0.85-0.96), and 0.93 (95% CI: 0.87-0.99), respectively.

The authors concluded that in vivo levels of omega-3 fatty acids including EPA, DPA, DHA, and EPA+DHA were not associated with increased risk of incident AF. Our data suggest the safety of habitual dietary intakes of omega-3 fatty acids with respect to AF risk. Coupled with the known benefits of these fatty acids in the prevention of adverse coronary events, our study suggests that current dietary guidelines recommending fish/omega-3 fatty acid consumption can be maintained.

Faced with contradictory results based on non-RCT evidence, we clearly need an RCT. Luckily such a trial has recently been published. It was an ancillary study of a 2 × 2 factorial randomized clinical trial involving 25 119 women and men aged 50 years or older without prior cardiovascular disease, cancer, or AF. Participants were recruited directly by mail between November 2011 and March 2014 from all 50 US states and were followed up until December 31, 2017.

Participants were randomized to receive EPA-DHA (460 mg/d of EPA and 380 mg/d of DHA) and vitamin D3 (2000 IU/d) (n = 6272 analyzed); EPA-DHA and placebo (n = 6270 analyzed); vitamin D3 and placebo (n = 6281 analyzed); or 2 placebos (n = 6296 analyzed). The primary outcome was incident AF confirmed by medical record review.

Among the 25 119 participants who were randomized and included in the analysis (mean age, 66.7 years; 50.8% women), 24 127 (96.1%) completed the trial. Over a median 5.3 years of treatment and follow-up, the primary end point of incident AF occurred in 900 participants (3.6% of study population). For the EPA-DHA vs placebo comparison, incident AF events occurred in 469 (3.7%) vs 431 (3.4%) participants, respectively (hazard ratio, 1.09; 95% CI, 0.96-1.24; P = .19). For the vitamin D3 vs placebo comparison, incident AF events occurred in 469 (3.7%) vs 431 (3.4%) participants, respectively (hazard ratio, 1.09; 95% CI, 0.96-1.25; P = .19). There was no evidence for interaction between the 2 study agents (P = .39).

The authors concluded that among adults aged 50 years or older, treatment with EPA-DHA or vitamin D3, compared with placebo, resulted in no significant difference in the risk of incident AF over a median follow-up of more than 5 years. The findings do not support the use of either agent for the primary prevention of incident AF.

So, does the regular supplementation with omega-3 fatty acids increase the risk of atrial fibrillation? The evidence is not entirely clear but, on balance, I conclude that the risk is low or even non-existent.

The concept that the outcomes of spinal manipulation therapy (SMT) – the hallmark intervention of chiropractors which they use on practically every patient – are optimized when the treatment is aimed at a clinically relevant joint is commonly assumed and central to teaching and clinical use of chiropractic. But is the assumption true?

This systematic review investigated whether clinical effects are superior when this is the case compared to SMT applied elsewhere. Eligible study designs were randomized controlled trials that investigated the effect of SMT applied to candidate versus non-candidate sites for spinal pain.

The authors obtained studies from four different databases. Risk of bias was assessed using an adjusted Cochrane risk of bias tool, adding four items for study quality. Between-group differences were extracted for any reported outcome or, when not reported, calculated from the within-group changes. Outcomes were compared for SMT applied at a ‘relevant’ site to SMT applied elsewhere. The authors prioritized methodologically robust studies when interpreting results.

Ten studies were included. They reported 33 between-group differences; five compared treatments within the same spinal region and five at different spinal regions.

None of the nine studies with low or moderate risk of bias reported statistically significant between-group differences for any outcome. The tenth study reported a small effect on pain (1.2/10, 95%CI – 1.9 to – 0.5) but had a high risk of bias. None of the nine articles of low or moderate risk of bias and acceptable quality reported that “clinically-relevant” SMT has a superior outcome on any outcome compared to “not clinically-relevant” SMT. This finding contrasts with ideas held in educational programs and clinical practice that emphasize the importance of joint-specific application of SMT.

The authors concluded that the current evidence does not support that SMT applied at a supposedly “clinically relevant” candidate site is superior to SMT applied at a supposedly “not clinically relevant” site for individuals with spinal pain.

I came across this study when I searched for the published work of Prof Stephen Perle, a chiropractor and professor at the School of Chiropractic, College of Health Sciences, University of Bridgeport, US, who recently started trolling me on this blog. Against my expectation, I find his study interesting and worthwhile.

His data quite clearly show that the effects of SMT are non-specific and mainly due to a placebo response. That in itself is not hugely remarkable and has been suspected to some time, e.g.:

What is remarkable, however, is the fact that Perle and his co-authors offer all sorts of other explanation for their findings without even seriously considering what is stareing in their faces:

SPINAL MANIPULATIONS ARE PLACEBOS

CHIROPRACTIC IS A PLACEBO THERAPY

This might be almost acceptable, if chiropractic would not also be burdened with significant risks (as we have discussed ad nauseam on this blog) – another fact of which chiros like Perle are in denial.

What does all that mean for patients?

The practical implication is fairly straight forward: the risk/benefit balance of chiropractic is negative. And this surely means the only responsible advice to patients is this:

NEVER CONSULT A CHIRO!

Autogenic training (AT) is a relaxation technique that has garnered attention for its potential to reduce anxiety and improve psychological well-being. This review aimed to synthesize the findings from a diverse range of studies investigating the relationship between AT and anxiety disorder across different populations and settings.

A comprehensive review of 162 studies, including randomised controlled trials (RCTs), non-randomized controlled trials (N-RCTs), surveys, and meta-analysis, was conducted and 29 studies were selected. Participants in the studies were patients with:

  • cancer,
  • bulimia nervosa,
  • stroke,
  • coronary angioplasty,

Others were nursing students, healthy volunteers, athletes, etc.

Anxiety levels were measured before and after the AT intervention using a variety of anxiety assessment scales, including the State Trait Anxiety Inventory (STAI) and the Hospital Anxiety and Depression Scale (HADS). The formats, duration, and delivery of the interventions varied, with some studies utilising guided sessions by professionals and other self-administered practises.

The combined findings of these studies revealed consistent trends in the beneficial effects of AT on anxiety reduction. AT was found to be effective in reducing anxiety symptoms across a wide range of populations and settings. Following AT interventions, participants reported reduced anxiety, improved mood states, and improved coping mechanisms. AT was found to be superior to no treatment or a comparable intervention in a number of cases.

The authors conclused that the body of evidence supports autogenic training as a non-pharmacological approach to reducing anxiety and improving psychological well-being. Despite differences in methodology and participant profiles, the studies show that AT has a positive impact on a wide range of populations. The findings merit further investigation and highlight AT’s potential contribution to anxiety management strategies.

I was taught AT many years ago and have practised it occasionally ever since. I have also co-authored several papers of AT that showed encouraging results, e.g.:

Thus, I feel that the conclusions of this review might be correct.

Several further recent papers seem to support the notion that AT is a treatment worth trying, e.g.:

Why then AT is not better studied and more popular? A short paragraph of my next book (to be published in about 6 months) on the inventors of so-called alternative medicines (SCAMs), including the German psychiatry professor Johannes Schulz (1884-1970), inventor of AT, might give you a clue:

Schultz supported the euthanasia program of the Nazis, i.e. the extermination of disabled and other people considered ‘unworthy of living’ during the Third Reich. He passed death sentences on “hysterical women” through his diagnoses. In 1933, Schultz began research on a guide-book on sexual education in which he focused on homosexuality and explored the topics of sterilization and euthanasia. In 1935, he published an essay about the psychological consequences of sterilization and castration among men; in it he supported compulsory sterilization of men in order to eliminate hereditary illnesses. With a diagnostic scheme developed by him in 1940, Schulz advocated the execution of mentally ill patients by stating: “I personally have to align myself with Mr. Hoche […], by recalling the ‘annihilation of life unworthy of life’ and by raising the hope that the madhouses will soon become emptied and remodelled according to this principle.” Schultz was fully aware of the consequences of his diagnostic assessment and even used the term “death sentence in the form of a diagnosis”.

I came across this evidence only years after having published my papers on AT. Would I have developed an interest in AT, if I had known about Schulz’s Nazi past? Probably not.

This review evaluated the magnitude of the placebo response of sham acupuncture in trials of acupuncture for nonspecific LBP, and assessed whether different types of sham acupuncture are associated with different responses. Four databases including PubMed, EMBASE, MEDLINE, and the Cochrane Library were searched through April 15, 2023, and randomized controlled trials (RCTs) were included if they randomized patients with LBP to receive acupuncture or sham acupuncture intervention. The main outcomes included the placebo response in pain intensity, back-specific function and quality of life. Placebo response was defined as the change in these outcome measures from baseline to the end of treatment. Random-effects models were used to synthesize the results, standardized mean differences (SMDs, Hedges’g) were applied to estimate the effect size.

A total of 18 RCTs with 3,321 patients were included. Sham acupuncture showed a noteworthy pooled placebo response in pain intensity in patients with LBP [SMD −1.43, 95% confidence interval (CI) −1.95 to −0.91, I2=89%]. A significant placebo response was also shown in back-specific functional status (SMD −0.49, 95% CI −0.70 to −0.29, I2=73%), but not in quality of life (SMD 0.34, 95% CI −0.20 to 0.88, I2=84%). Trials in which the sham acupuncture penetrated the skin or performed with regular needles had a significantly higher placebo response in pain intensity reduction, but other factors such as the location of sham acupuncture did not have a significant impact on the placebo response.

The authors concluded that sham acupuncture is associated with a large placebo response in pain intensity among patients with LBP. Researchers should also be aware that the types of sham acupuncture applied may potentially impact the evaluation of the efficacy of acupuncture. Nonetheless, considering the nature of placebo response, the effect of other contextual factors cannot be ruled out in this study.

As the authors stated in their conclusion: the effect of other contextual factors cannot be ruled out. I would go much further and say that the outcomes noted here are mostly due to effects other than placebo. Obvious candidates are:

  • regression towards the mean;
  • natural history of the condition;
  • success of patient blinding;
  • social desirability.

To define the placebo effect in acupuncture trials as the change in the outcome measures from baseline to the end of treatment – as the authors of the review do – is not just naive, it is plainly wrong. I would not be surprised, if different sham acupuncture treatments have different effects. To me this would be an expected, plausible finding. But such differences just cannot be estimated in the way the authors suggest. For that, we would need an RCT in which patients are randomized to be treated in the same setting with a range of different types of sham acupuncture. The results of such a study might be revealing but I doubt that many ethics committees would be happy to grant their approval for it.

In the absence of such data, the best we can do is to design trials such that the verum is tested against a credible placebo which, for patients, is indistinguishable from the verum, while demonstrating that blinding is successful.

Manual therapy is considered a safe and less painful method and has been increasingly used to alleviate chronic neck pain. However, there is controversy about the effectiveness of manipulation therapy on chronic neck pain. Therefore, this systematic review and meta-analysis of randomized controlled trials (RCTs) aimed to determine the effectiveness of manipulative therapy for chronic neck pain.

A search of the literature was conducted on seven databases (PubMed, Cochrane Center Register of Controlled Trials, Embase, Medline, CNKI, WanFang, and SinoMed) from the establishment of the databases to May 2022. The review included RCTs on chronic neck pain managed with manipulative therapy compared with sham, exercise, and other physical therapies. The retrieved records were independently reviewed by two researchers. Further, the methodological quality was evaluated using the PEDro scale. All statistical analyses were performed using RevMan V.5.3 software. The Grading of Recommendations, Assessment, Development and Evaluations (GRADE) assessment was used to evaluate the quality of the study results.

Seventeen RCTs, including 1190 participants, were included in this meta-analysis. Manipulative therapy showed better results regarding pain intensity and neck disability than the control group. Manipulative therapy was shown to relieve pain intensity (SMD = -0.83; 95% confidence interval [CI] = [-1.04 to -0.62]; p < 0.0001) and neck disability (MD = -3.65; 95% CI = [-5.67 to – 1.62]; p = 0.004). However, the studies had high heterogeneity, which could be explained by the type and control interventions. In addition, there were no significant differences in adverse events between the intervention and the control groups.

The authors concluded that manipulative therapy reduces the degree of chronic neck pain and neck disabilities.

Only a few days ago, we discussed another systematic review that drew quite a different conclusion: there was very low certainty evidence supporting cervical SMT as an intervention to reduce pain and improve disability in people with neck pain. Image result for systematic review, cartoon

How can this be?

Systematic reviews are supposed to generate reliable evidence!

How can we explain the contradiction?

There are several differences between the two papers:

  • One was published in a SCAM journal and the other one in a mainstream medical journal.
  • One was authored by Chinese researchers, the other one by an international team.
  • One included 17, the other one 23 RCTs.
  • One assessed ‘manual/manipulative therapies’, the other one spinal manipulation/mobilization.

The most profound difference is that the review by the Chinese authors is mostly on Chimese massage [tuina], while the other paper is on chiropractic or osteopathic spinal manipulation/mobilization. A look at the Chinese authors’ affiliation is revealing:

  • Department of Tuina and Spinal Diseases Research, The Third School of Clinical Medicine (School of Rehabilitation Medicine), Zhejiang Chinese Medical University, Hangzhou, China.
  • Department of Tuina and Spinal Diseases Research, The Third School of Clinical Medicine (School of Rehabilitation Medicine), Zhejiang Chinese Medical University, Hangzhou, China; Department of Tuina, The Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China. Electronic address: [email protected].
  • Department of Tuina and Spinal Diseases Research, The Third School of Clinical Medicine (School of Rehabilitation Medicine), Zhejiang Chinese Medical University, Hangzhou, China; Department of Tuina, The Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China. Electronic address: [email protected].

What lesson can we learn from this confusion?

Perhaps that Tuina is effective for neck pain?

No!

What the abstract does not tell us is that the Tuina studies are of such poor quality that the conclusions drawn by the Chinese authors are not justified.

What we do learn – yet again – is that

  1. Chinese papers need to be taken with a large pintch of salt. In the present case, the searches underpinning the review and the evaluations of the included primary studies were clearly poorly conducted.
  2. Rubbish journals publish rubbish papers. How could the reviewers and the editors have missed the many flaws of this paper? The answer seems to be that they did not care. SCAM journals tend to publish any nonsense as long as the conclusion is positive.

 

This systematic review with meta-analysis of randomized clinical trials (RCTs) estimated the benefits and harms of cervical spinal manipulative therapy (SMT) for treating neck pain. The authors searched the MEDLINE, Cochrane CENTRAL, EMBASE, CINAHL, PEDro, Chiropractic Literature Index bibliographic databases, and grey literature sources, up to June 6, 2022.Image result for death by neck manipulation

RCTs evaluating SMT compared to guideline-recommended and non-recommended interventions, sham SMT, and no intervention for adults with neck pain were eligible. Pre-specified outcomes included pain, range of motion, disability, health-related quality of life.

A total of 28 RCTs could be included. There was very low to low certainty evidence that SMT was more effective than recommended interventions for improving pain at short-term (standardized mean difference [SMD] 0.66; confidence interval [CI] 0.35 to 0.97) and long-term (SMD 0.73; CI 0.31 to 1.16), and for reducing disability at short-term (SMD 0.95; CI 0.48 to 1.42) and long-term (SMD 0.65; CI 0.23 to 1.06). Only transient side effects were found (e.g., muscle soreness).

The authors concluded that there was very low certainty evidence supporting cervical SMT as an intervention to reduce pain and improve disability in people with neck pain.

Harms cannot be adequately investigated on the basis of RCT data. Firstly, because much larger sample sizes would be required for this purpose. Secondly, RCTs of spinal manipulation very often omit reporting adverse effects (as discussed repeatedly on this bolg). If we extend our searches beyond RCTs, we find many cases of serious harm caused by neck manipulations (also as discussed repeatedly on this bolg). Therefore, the conclusion of this review should be corrected:

Low certainty evidence exists supporting cervical SMT as an intervention to reduce pain and improve disability in people with neck pain. The evidence of harm is, however, substantial. It follows that the risk/benefit ratio is not positive. Cervical SMT should therefore be discouraged.

This systematic review and meta-analysis assessed the effectiveness of visceral osteopathy in improving pain intensity, disability and physical function in patients with low-back pain (LBP).

MEDLINE (Pubmed), PEDro, SCOPUS, Cochrane Library and Web of Science databases were searched from inception to February 2022. PICO search strategy was used to identify randomized clinical trials applying visceral techniques in patients with LBP. Eligible studies and data extraction were conducted independently by two reviewers. Quality of the studies was assessed with the Physiotherapy Evidence Database scale, and the risk of bias with Cochrane Collaboration tool. Meta-analyses were conducted using random effects models according to heterogeneity assessed with I2 coefficient. Data on outcomes of interest were extracted by a researcher using RevMan 5.4 software.

Five studies were included in the systematic review involving 268 patients with LBP. The methodological quality of the included ranged from high to low and the risk of bias was high. Visceral osteopathy techniques have shown no improvements in pain intensity (Standardized mean difference (SMD) = -0.53; 95% CI; -1.09, 0.03; I2: 78%), disability (SMD = -0.08; 95% CI; -0.44, 0.27; I2: 0%) and physical function (SMD = -0.26; 95% CI; -0.62, 0.10; I2: 0%) in patients with LBP.

The authors concluded that this systematic review and meta-analysis showed a lack of high-quality studies showing the effectiveness of visceral osteopathy in pain, disability, and physical function in patients with LBP.

Visceral osteopathy (or visceral manipulation) is an expansion of the general principles of osteopathy and involves the manual manipulation by a therapist of internal organs, blood vessels and nerves (the viscera) from outside the body.

Visceral osteopathy was developed by Jean-Piere Barral, a registered Osteopath and Physical Therapist who serves as Director (and faculty) of the Department of Osteopathic Manipulation in Paris, France. He stated that through his clinical work with thousands of patients, he created this modality based on organ-specific fascial mobilization. And through work in a dissection lab, he was able to experiment with visceral manipulation techniques and see the internal effects of the manipulations.[1]  According to its proponents, visceral manipulation is based on the specific placement of soft manual forces looking to encourage the normal mobility, tone and motion of the viscera and their connective tissues. These gentle manipulations may potentially improve the functioning of individual organs, the systems the organs function within, and the structural integrity of the entire body.[2] Visceral osteopathy comprises of several different manual techniques firstly for diagnosing a health problem and secondly for treating it.

Several studies have assessed the diagnostic reliability of the techniques involved. The totality of this evidence fails to show that they are sufficiently reliable to be od practical use.[3] Other studies have tested whether the therapeutic techniques used in visceral osteopathy are effective in curing disease or alleviating symptoms. The totality of this evidence fails to show that visceral osteopathy works for any condition.[4] 

The treatment itself seems to be safe, yet the risks of visceral osteopathy are nevertheless considerable: if a patient suffers from symptoms related to her inner organs, the therapist is likely to misdiagnose them and subsequently mistreat them. If the symptoms are due to a serious disease, this would amount to medical neglect and could, in extreme cases, cost the patient’s life.

My bottom line: if you see visceral osteopathy being employed anywhere, turn araound and seek proper healthcare whatever your illness might be.

References

[1]  https://www.barralinstitute.com/about/jean-pierre-barral.php .

[2]  http://www.barralinstitute.co.uk/ .

[3] Guillaud A, Darbois N, Monvoisin R, Pinsault N (2018) Reliability of diagnosis and clinical efficacy of visceral osteopathy: a systematic review. BMC Complement Altern Med 18:65

[4]  http://www.barralinstitute.co.uk/ .

As we have recently discussed diet and its effects on health, it seems reasonable to ask whether there is a diet that is demonstrably healthy. A recent investigation attempted to answer this question.

This study was aimed at developing a healthy diet score that is associated with health outcomes and is globally applicable. It used data from the Prospective Urban Rural Epidemiology (PURE) study and tried to replicate it in five independent studies on a total of 245 000 people from 80 countries.

A healthy diet score was developed on the basis of the data from 147 642 people from the general population, from 21 countries in the PURE study. The consistency of the associations of the score with events was examined in five large independent studies from 70 countries.

The healthy diet score was developed based on six foods each of which has been associated with a significantly lower risk of mortality [i.e. fruit, vegetables, nuts, legumes, fish, and dairy (mainly whole-fat); range of scores, 0–6]. The main outcome measures were all-cause mortality and major cardiovascular events [cardiovascular disease (CVD)].

During a median follow-up of 9.3 years in PURE, compared with a diet score of ≤1 point, a diet score of ≥5 points was associated with a lower risk of:

  • mortality [hazard ratio (HR) 0.70; 95% confidence interval (CI) 0.63–0.77)],
  • CVD (HR 0.82; 0.75–0.91),
  • myocardial infarction (HR 0.86; 0.75–0.99),
  • stroke (HR 0.81; 0.71–0.93).

In three independent studies with vascular patients, similar results were found, with a higher diet score being associated with lower mortality (HR 0.73; 0.66–0.81), CVD (HR 0.79; 0.72–0.87), myocardial infarction (HR 0.85; 0.71–0.99), and a non-statistically significant lower risk of stroke (HR 0.87; 0.73–1.03). Additionally, in two case-control studies, a higher diet score was associated with lower first myocardial infarction [odds ratio (OR) 0.72; 0.65–0.80] and stroke (OR 0.57; 0.50–0.65). A higher diet score was associated with a significantly lower risk of death or CVD in regions with lower than with higher gross national incomes (P for heterogeneity <0.0001). The PURE score showed slightly stronger associations with death or CVD than several other common diet scores (P < 0.001 for each comparison).

Association of Prospective Urban Rural Epidemiology healthy diet score vs. Events in those with and without prior cardiovascular disease in the four independent prospective studies (n = 191 476). Hazard ratios (95%) are per 20 percentile increment in the diet score. Hazard ratios (95% CI) are multivariable adjusted.

The authors concluded that consumption of a diet comprised of higher amounts of fruits, vegetables, nuts, legumes, and a moderate amount of fish and whole-fat dairy is associated with a lower risk of CVD and mortality in all world regions, but especially in countries with lower income where consumption of these natural foods is low. Similar associations were found with the inclusion of meat or whole grain consumption in the diet score (in the ranges common in the six studies that we included). Our findings indicate that the risks of deaths and vascular events in adults globally are higher with inadequate intake of protective foods.

The authors rightly stress that their analyses have a number of limitations:

First, diet (as in most large epidemiologic studies) was self-reported and variations in reporting might lead to random errors that could dilute real associations between diet scores and clinical outcomes. Therefore, the beneficial effects of a healthier diet may be larger than estimated.

Second, the researchers did not examine the role of individual types of fruits and vegetables as components in the diet score, since the power to detect associations of the different types of fruits and vegetables vs. CVD or mortality is low (i.e. given that the number of events per type of fruit and vegetable was relatively low). Recent evidence suggests that bioactive compounds and, in particular, polyphenols which are found in certain fruit or vegetables (e.g. berries, spinach, and beans) may be especially protective against CVD.

Third, in observational studies, the possibility of residual confounding from unquantified or imprecise measurement of covariates cannot be ruled out—especially given that the differences in risk of clinical events are modest (∼10%–20% relative differences). Ideally, large randomized trials would be needed to clarify the clinical impact on events of a policy of proposing a dietary pattern in populations.

Fourth, the use of the median intake of each food component as a cut-off in the scoring scheme for each diet may not reflect the full range of consumption or provide a meaningful indicator of consumption associated with the disease. However, the use of quintiles instead of medians within each study or within each region yielded the same results indicating the robustness of our findings.

Fifth, the level of intake to meet the cut-off threshold for each food group in the diet score may differ between countries. However, in sensitivity analyses where region-specific median cut-offs were used to classify participants on each component of the diet score, the results were similar to using the overall cohort median of each food component. Further, with unprocessed red meat and whole grains included or excluded from the diet score in these sensitivity analyses, the results were again similar.

Sixth, misclassification of exposures cannot be ruled out as repeat measures of diet were not available in all studies. However, the ORIGIN study, in which repeat diet assessments at 2 years were conducted, showed similar results based on the first vs. second diet assessments. This indicates that misclassification of dietary intake during follow-up was not undermining the findings.

Seventh, one unique aspect of the study is the focus on only protective foods, i.e. a dietary pattern score that highlights what is missing from the food supply, especially in poorer world regions, but this does not negate the importance of limiting the consumption of harmful foods such as highly processed foods. While the PURE diet score had significantly stronger associations with events than other diet scores, the HRs were only slightly larger for PURE than for most other diet scores. However, the Planetary score was the least predictive of events. The analyses provide empirical evidence that all diet scores (other than the Planetary diet score) are of value to predicting death or CVD globally and in all regions of the world.

So, what should we, according to these findings, be looking for and how much of it should we consume? Here is the table that should answer these questions:

Fruits and vegetables 4 to 5 servings daily 1 medium apple, banana, pear; 1 cup leafy vegs; 1/2 cup other vegs
Legumes 3 to 4 servings weekly 1/2 cup beans or lentils
Nuts 7 servings weekly 1 oz., tree nuts or peanuts
Fish 2 to 3 servings weekly 3 oz. cooked (pack of cards size)
Dairy 14 servings weekly 1 cup milk or yogurt; 1 ½ oz cheese
Whole grainsc Moderate amounts (e.g. 1 serving daily) can be part of a healthy diet 1 slice (40 g) bread; ½ medium (40 g) flatbread; ½ cup (75–120 g) cooked rice, barley, buckwheat, semolina, polenta, bulgur, or quinoa
Unprocessed meatsc Moderate amounts (e.g. 1 serving daily) can be part of a healthy diet 3 oz. cooked red meat or poultry

There is widespread agreement amongst clinicians that people with non-specific low back pain (NSLBP) comprise a heterogeneous group and that their management should be individually tailored. One treatment known by its tailored design is the McKenzie method (e.g. an individualized program of exercises based on clinical clues observed during assessment) used mostly but not exclusively by physiotherapists.

A recent Cochrane review evaluated the effectiveness of the McKenzie method in people with (sub)acute non-specific low back pain. Randomized clinical trials (RCTs) investigating the effectiveness of the McKenzie method in adults with (sub)acute (less than 12 weeks) NSLBP.

Five RCTs were included with a total of 563 participants recruited from primary or tertiary care. Three trials were conducted in the USA, one in Australia, and one in Scotland. Three trials received financial support from non-commercial funders and two did not provide information on funding sources. All trials were at high risk of performance and detection bias. None of the included trials measured adverse events.

McKenzie method versus minimal intervention (educational booklet; McKenzie method as a supplement to other intervention – main comparison) There is low-certainty evidence that the McKenzie method may result in a slight reduction in pain in the short term (MD -7.3, 95% CI -12.0 to -2.56; 2 trials, 377 participants) but not in the intermediate term (MD -5.0, 95% CI -14.3 to 4.3; 1 trial, 180 participants). There is low-certainty evidence that the McKenzie method may not reduce disability in the short term (MD -2.5, 95% CI -7.5 to 2.0; 2 trials, 328 participants) nor in the intermediate term (MD -0.9, 95% CI -7.3 to 5.6; 1 trial, 180 participants).

McKenzie method versus manual therapy There is low-certainty evidence that the McKenzie method may not reduce pain in the short term (MD -8.7, 95% CI -27.4 to 10.0; 3 trials, 298 participants) and may result in a slight increase in pain in the intermediate term (MD 7.0, 95% CI 0.7 to 13.3; 1 trial, 235 participants). There is low-certainty evidence that the McKenzie method may not reduce disability in the short term (MD -5.0, 95% CI -15.0 to 5.0; 3 trials, 298 participants) nor in the intermediate term (MD 4.3, 95% CI -0.7 to 9.3; 1 trial, 235 participants).

McKenzie method versus other interventions (massage and advice) There is very low-certainty evidence that the McKenzie method may not reduce disability in the short term (MD 4.0, 95% CI -15.4 to 23.4; 1 trial, 30 participants) nor in the intermediate term (MD 10.0, 95% CI -8.9 to 28.9; 1 trial, 30 participants).

The authors concluded that, based on low- to very low-certainty evidence, the treatment effects for pain and disability found in our review were not clinically important. Thus, we can conclude that the McKenzie method is not an effective treatment for (sub)acute NSLBP.

 The hallmark of the McKenzie method for back pain involves the identification and classification of nonspecific spinal pain into homogenous subgroups. These subgroups are based on the similar responses of a patient’s symptoms when subjected to mechanical forces. The subgroups include postural syndrome, dysfunction syndrome, derangement syndrome, or “other,” with treatment plans directed to each subgroup. The McKenzie method emphasizes the centralization phenomenon in the assessment and treatment of spinal pain, in which pain originating from the spine refers distally, and through targeted repetitive movements the pain migrates back toward the spine. The clinician will then use the information obtained from this assessment to prescribe specific exercises and advise on which postures to adopt or avoid. Through an individualized treatment program, the patient will perform specific exercises at home approximately ten times per day, as opposed to 1 or 2 physical therapy visits per week. According to the McKenzie method, if there is no restoration of normal function, tissue healing will not occur, and the problem will persist.

Classification:

The postural syndrome is pain caused by mechanical deformation of soft tissue or vasculature arising from prolonged postural stresses. These may affect the joint surfaces, muscles, or tendons, and can occur in sitting, standing, or lying. Pain may be reproducible when such individuals maintain positions or postures for sustained periods. Repeated movements should not affect symptoms, and relief of pain typically occurs immediately following the correction of abnormal posture.

The dysfunction syndrome is pain caused by the mechanical deformation of structurally impaired soft tissue; this may be due to traumatic, inflammatory, or degenerative processes, causing tissue contraction, scarring, adhesion, or adaptive shortening. The hallmark is a loss of movement and pain at the end range of motion. Dysfunction has subsyndromes based upon the end-range direction that elicits this pain: flexion, extension, side-glide, multidirectional, adherent nerve root, and nerve root entrapment subsyndromes. Successful treatment focuses on patient education and mobilization exercises that focus on the direction of the dysfunction/direction of pain. The goal is on tissue remodeling which can be a prolonged process.

The derangement syndrome is the most commonly encountered pain syndrome, reported in one study to have a prevalence as high as 78% of patients classified by the McKenzie method. It is caused by an internal dislocation of articular tissue, causing a disturbance in the normal position of affected joint surfaces, deforming the capsule, and periarticular supportive ligaments. This derangement will both generate pain and obstruct movement in the direction of the displacement. There are seven different subsyndromes which are classified by the location of pain and the presence, or absence, of deformities. Pain is typically elicited by provocative assessment movements, such as flexion or extension of the spine. The centralization and peripheralization of symptoms can only occur in the derangement syndrome. Thus the treatment for derangement syndrome focuses on repeated movement in a single direction that causes a gradual reduction in pain. Studies have shown approximately anywhere between 58% to 91% prevalence of centralization of lower back pain. Studies have also shown that between 67% to 85% of centralizers displayed the directional preference for a spinal extension. This preference may partially explain why the McKenzie method has become synonymous with spinal extension exercises. However, care must be taken to accurately diagnose the direction of pain, as one randomized controlled study has shown that giving the ‘wrong’ direction of exercises can actually lead to poorer outcomes.

Other or Nonmechanical syndrome refers to any symptom that does not fit in with the other mechanical syndromes, but exhibits signs and symptoms of other known pathology; Some of these examples include spinal stenosis, sacroiliac disorders, hip disorders, zygapophyseal disorders, post-surgical complications, low back pain secondary to pregnancy, spondylolysis, and spondylolisthesis.

CONCLUSION:

“Internationally researched” and found to be ineffective!

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