Wednesday, February 27, 2019

Wisdom Wednesday: Fecal Immunochemical Tests


Performance Characteristics of Fecal Immunochemical Tests for Colorectal Cancer and Advanced Adenomatous Polyps: A Systematic Review and Meta-analysis

Purpose:
To summarize performance characteristics of FITs for CRC and advanced adenomas in average-risk persons undergoing screening colonoscopy (reference standard) and to identify factors affecting these characteristics.

Data Sources:
Ovid MEDLINE, PubMed, Embase, and the Cochrane Library from inception through October 2018; reference lists of studies and reviews.

Study Selection:
Two reviewers independently screened records to identify published English-language prospective or retrospective observational studies that evaluated FIT sensitivity and specificity for colonoscopic findings in asymptomatic, average-risk adults.

Data Extraction:
Two authors independently extracted data and evaluated study quality.

Data Synthesis:
Thirty-one studies (120 255 participants; 18 FITs) were included; all were judged to have low to moderate risk of bias. Performance characteristics depended on the threshold for a positive result. A threshold of 10 µg/g resulted in sensitivity of 0.91 (95% CI, 0.84 to 0.95) and a negative likelihood ratio of 0.10 (CI, 0.06 to 0.19) for CRC, whereas a threshold of greater than 20 µg/g resulted in specificity of 0.95 (CI, 0.94 to 0.96) and a positive likelihood ratio of 15.49 (CI, 9.82 to 22.39). For advanced adenomas, sensitivity was 0.40 (CI, 0.33 to 0.47) and the negative likelihood ratio was 0.67 (CI, 0.57 to 0.78) at 10 µg/g, and specificity was 0.95 (CI, 0.94 to 0.96) and the positive likelihood ratio was 5.86 (CI, 3.77 to 8.97) at greater than 20 µg/g. Studies had low to high heterogeneity, depending on the threshold. Although several FITs had adequate performance, sensitivity and specificity for CRC for 1 qualitative FIT were 0.90 and 0.91, respectively, at its single threshold of 10 µg/g; positive and negative likelihood ratios were 10.13 and 0.11, respectively. Comparison of 3 FITs at 3 thresholds was inconclusive: CIs overlapped, and the comparisons were across rather than within studies.

Limitations:
Only English-language studies were included. Incomplete reporting limited quality assessment of some evidence. Performance characteristics are for 1-time rather than serial testing.

Conclusion:
Single-application FITs have moderate to high sensitivity and specificity for CRC, depending on the positivity threshold. Sensitivity of 1-time testing for advanced adenomas is low, regardless of the threshold.

Primary Funding Source:
Department of Medicine, Indiana University School of Medicine.

My Take:
This is an abstract taken directly from the Annals of Internal Medicine, February 26, 2019. Typically I “dummy it down” a little, but I thought you might find the original abstract interesting. It’s a retrospective study using two independent authors as noted above. Please note how they not only present the data, but also the limitations prior to any conclusions. Finally, they also list the funding. In this case, it appears to be independent of bias.

Bottom Line:
Cologuard is the most popular trade name for this home test. It is available by prescription only but is covered by most insurance. Despite the limitation in testing for advanced adenomas, it is quite accurate in testing for colorectal cancer. I highly recommend you ask your primary care provider to add this test to your annual physical.

Monday, February 25, 2019

Colorectal Cancer: Scientists halt growth with cannabinoid compounds

Scientists have identified several cannabinoid compounds that could potentially treat colorectal cancer. A team at Pennsylvania State University College of Medicine in Hershey tested hundreds of cannabinoids on various types of human colorectal cancer cells in the laboratory. Of these, 10 synthetic cannabinoids showed the ability to stop cancer cell growth. The well-known cannabis compounds tetrahydrocannabinol (THC) and cannabidiol (CBD) showed negligible ability to do the same.

The researchers see their findings as a starting point for further studies to better understand the anticancer effects that they observed, and to evaluate the compounds' potential for drug development. They report their results in a paper that features in the journal Cannabis and Cannabinoid Research. "Now that we've identified the compounds that we think have this activity," says senior study author Prof. Kent E. Vrana, who is chair of the Department of Pharmacology, "we can take these compounds and start trying to alter them to make them more potent against cancer cells." "And then, eventually, we can explore the potential for using these compounds to develop drugs for treating cancer," he adds.

According to the World Cancer Research Fund, colorectal cancer is the "third most common cancer worldwide." This is also the case in the United States, where a national surveillance program has estimated that colorectal cancer accounted for 8.1 percent of all new cancer incidences in 2018.

For several decades, overall rates of colorectal cancer diagnoses and deaths have been falling steadily in the U.S. Experts attribute this largely to changes in risk factors, more widespread screening, and better treatments. However, this overall decline masks an opposite trend in that rates and deaths to colorectal cancer are rising among those of 50 years of age and under. The reasons for this remain unclear, although some suggest that obesity, changes in diet, and an increase in sedentary lifestyles may be involved.

Friday, February 22, 2019

Researchers Discover Almost 2,000 New Gut Bacteria

According to numerous recent studies, human gut bacterial populations are capable of influencing various aspects of our physical and mental health. Despite this, many bacteria remain "unmapped" by scientists. A new study has now uncovered approximately 2,000 previously unknown gut bacteria.

Recent studies covered by Medical News Today have shown that the gut microbiota could have a role in Parkinson's disease and dementia, and they may explain why type 2 diabetes medication works well for some but not for others.

New research — appearing yesterday in the journal Nature — has now identified almost 2,000 new gut bacterial species that scientists have never cultured in a lab before.

"In this study," Almeida explains, "we leveraged the most comprehensive public databases of gastrointestinal bacteria to identify bacterial species that have not been seen before. The analysis methods we used are highly reproducible and can be applied to larger, more diverse datasets in the future, enabling further discovery."

In the future, the researchers hope that this and similar studies will further aid their understanding of the human gut, which, in turn, will contribute to developing better treatments of a variety of conditions.

Research such as this is helping us create a so-called blueprint of the human gut, which, in the future, could help us understand human health and disease better and could even guide diagnosis and treatment of gastrointestinal diseases."

Wednesday, February 20, 2019

Wisdom Wednesday: Zinc and Hypertension


New research links zinc deficiency to hypertension. Zinc is involved with hundreds of enzyme systems and has other health implications. Zinc has been shown to be beneficial for learning and cognition  and is also recommended for people with a genetic predisposition to heart disease. It may even mitigate certain degenerative effects of aging. Some research indicates zinc deficiency may be a component of dementia.

The link to zinc deficiency and hypertension has been shown in an earlier cohort study, and a new animal study suggests a possible mechanism. Zinc deficient mice were compared to those with normal zinc levels. The researchers found that the zinc deficient mice had decreased sodium excretion and, therefore, higher blood pressure when compared to healthy controls. Zinc deficiency increases blood pressure by causing an upregulation of sodium chloride cotransporter (NCC) and a decrease in sodium excretion.

The researchers stated, “This study links dysregulated renal sodium handling to zinc deficiency induced hypertension. Furthermore, NCC is identified as a novel mechanism by which zinc regulates blood pressure. Understanding the mechanisms of zinc deficiency induced BP dysregulation may have important therapeutic impact on hypertension.”

My Take:
For years, what little attention to diet and hypertension has focused on limiting sodium intake. Unfortunately, conventional health care does not differentiate between organically bound sodium (think celery) and inorganic sodium (added to processed meats). The latter is associated with hypertension, not the former.

Monday, February 18, 2019

Just 8 weeks of Yoga Benefit Rheumatoid Arthritis

New research, published in the journal Restorative Neurology and Neuroscience, finds that an 8-week regimen of intensive yoga eases both the physical symptoms of rheumatoid arthritis and the psychological distress that usually accompanies the condition.

Dr. Rima Dada, Ph.D., who is a professor in the Department of Anatomy at the All India Institute of Medical Sciences in New Delhi, led the new research.

Rheumatoid arthritis (RA) is a chronic inflammatory condition that affects approximately 1.3 million people in the United States. The disease is most likely autoimmune, which means that the immune system mistakes the body's own tissues and cartilage as foreign and attacks them. While there is no cure for RA, there are a variety of medications available. However, as Dr. Dada and her colleagues explain in their paper, recovery depends on various factors, some of which are psychological. Depression, for instance, often occurs alongside RA, and it can negatively affect a person's outcome.

In this context, Dr. Dada and team wondered if a yoga-based mind-body intervention could ease depressive symptoms in RA and help achieve remission of this chronic disease. To find out, Dr. Dada and colleagues examined the effects of practicing yoga intensively in 72 people with RA.

The scientists divided the study participants into two groups. Both groups continued to take disease-modifying antirheumatic drugs (DMARDs), which are the drugs doctors typically prescribe for this condition. Also, one group engaged in 120-minute sessions of yoga five times a week, for 8 weeks. The two main outcomes the researchers assessed were disease activity and depression severity. After the intervention, improvements in markers of neuroplasticity, inflammation, cellular health, and cellular aging — such as oxidative stress — showed that yoga had a positive effect on those who practiced it.

Dr. Dada and colleagues conclude, "Yoga, a mind-body intervention reestablished immunological tolerance by aiding remission at molecular and cellular level along with significant reduction in depression." "Thus in this inflammatory arthritis with a major psychosomatic component, yoga can be used as a complementary/adjunct therapy." The study's lead author reports, "Our findings show measurable improvements for the patients in the test group, suggesting an immune-regulatory role of yoga practice in the treatment of RA."

"An intensive yoga regimen," she continued, "concurrent with routine drug therapy induced molecular remission and re-established immunological tolerance. In addition, it reduced the severity of depression by promoting neuroplasticity."


Friday, February 15, 2019

PROBIOTICS MAY DIRECTLY AFFECT BREAST MILK CARBOHYDRATE COMPOSITION

New research has revealed a possible two-way connection between maternal dietary microbes and the makeup of the oligosaccharide sugar molecules found in human breast milk.

Until recently, it was thought that oligosaccharides affected the microbial communities within an infant’s gut, acting as prebiotics that then decreased their risk of certain infections, conditions and diseases. Studies showed that a woman’s genetics could determine the presence of between 23 and 130 oligosaccharides in her breast milk, and that the range of sugars was related to her blood type.

However, a new Finish study has shown that the probiotics that enter a woman’s digestive body orally may further affect her breast milk, changing which sugars occur within it. The study analyzed the breast milk 81 pregnant women, some of whom were administered probiotics, and others that were not, and found distinct oligosaccharide compositions in the milk of the two groups.

This study is important on a number of levels. It is the first time that a causal relationship has been discovered between friendly bacteria and human breast milk carbohydrate polymers. This breakthrough could have great consequences for infant as well as general human health.

Breast milk oligosaccharides play a key role in the healthy development of an infant’s immune system and directly affect the child’s ability to fight ill health. For example, some of the sugars in question have been associated many benefits, including a reduced incidence of diarrhea, gastroenteritis, respiratory tract infections and other immune-mediated and infectious diseases during the first few years of life, as well as the promotion of immune development and inflammatory response regulation.

Wednesday, February 13, 2019

Wisdom Wednesday: Statins Lower Risk for CV Events in Elders, But Benefits for Primary Prevention Still in Question


Statin therapy lowers the risk for vascular events in adults over age 70, according to a meta-analysis in The Lancet. However, the benefit seems apparent only in those with a history of vascular disease.

Researchers examined data from 28 randomized trials that either compared statin use with nonuse or compared intensive statin regimens with standard treatment. Over 185,000 participants were included, of whom 15% were age 71–75 and 8% were older than 75.

During roughly 5 years' follow-up, statin use or intensive treatment was associated with a significant reduction in major vascular events across all age groups — overall, a 21% reduction in risk with each 1-mmol/L (39-mg/dL) decrease in LDL cholesterol. However, when stratified by history of vascular disease, a significant benefit among those aged 71 and older was limited to those with prior vascular disease.

My Take:
The full article is available online from The Lancet. These findings are strikingly similar to those found with aspirin – it’s best used for patients with a history of cardiovascular disease than for prevention.

Monday, February 11, 2019

Hip Arthroscopy Outperforms PT for Femoroacetabular Impingement

Arthroscopic surgery may be superior to physical therapy for patients with femoroacetabular impingement (FAI), according to a U.K.-based study in The BMJ. FAI, which affects roughly one-fifth of the general population, is characterized by adverse morphology causing the femoral neck to impact against the acetabular rim; this predisposes patients to premature degeneration of the joint.

Over 200 adults with symptomatic, confirmed FAI were randomized to either physical therapy plus activity modification or arthroscopic surgery to remove the impinging femoral and acetabular bone. The primary outcome — a 100-point score on an activities of daily living measure at 8 months post-randomization — favored the surgery group by 10 points. Secondary outcomes, including sports and depression scores, also favored the surgery group.

The researchers caution: "Although arthroscopic hip surgery seems superior to physiotherapy and activity modification, patients must be informed of the potential risks and benefits of surgery, including the risk of no improvement. Up to a half of patients may not achieve a clinically important improvement after surgery; hence accurate patient selection is critical to optimizing treatment outcomes." They note, for example, that osteoarthritis may negatively affect the surgery's outcomes.

My Take:
The full article is available for free from The BMJ (The British Medical Journal) CLICK HERE.

Manipulation of the femoral head is an excellent alternative to the arthroscopic surgery and can be combined with physical therapy for much improved outcomes. Clinically, I find that manipulation will also provide good temporary relief for a torn labrum as well, but ultimately a labral tear will require surgery.

The conservative approach is to try manipulation and physical therapy for up to three months. If significant improvement is not achieved then arthroscopic surgery can be performed before osteoarthritis becomes a factor. Most surgeons agree that the window for successful surgery closes around six months after symptoms appear.

It is interesting to note that the results of this study on hip surgery are the opposite of similar studies on knee and shoulder surgery. Please review my blog “No Surgery for Subacromial Pain Syndrome” posted last Friday. Outcomes for hip surgery traditionally are better than surgery on the knee or shoulder. Just look at the recovery times for people you know having a hip replacement versus those having a knee replacement.

Bottom Line:
Whenever possible take the conservative route first to rehabilitate a joint rather than operate. In the worst case scenario, the rehabilitation prior to surgery will improve outcomes even if the therapy fails and surgery is still required. Obviously, the better outcome is to avoid the surgery altogether.


Source: February 12, 2019 New England Journal of Medicine

Friday, February 8, 2019

No Surgery for Subacromial Pain Syndrome

Subacromial decompression surgery should not be offered to patients with subacromial pain syndrome, according to a new guideline from The BMJ's Rapid Recommendations panel. The guidance — considered a strong recommendation — applies to patients with atraumatic shoulder pain, including rotator cuff disease, lasting longer than 3 months.

The recommendation was based on findings from seven randomized trials among roughly 1000 patients that compared decompression surgery with either sham surgery or exercise alone. Overall, decompression surgery did not provide a meaningful benefit over nonsurgical treatment in terms of pain, function, or quality-of-life. However, surgery was associated with more cases of frozen shoulder (12 more cases per 1000 patients undergoing surgery) and could cause more serious adverse events like major bleeding.

The panel, which included patients, clinicians, and researchers, concluded: "Almost all informed patients would choose to avoid surgery.... However, there is substantial uncertainty in what alternative treatment is best."

My Take:
The full article is available for free online from the New England Journal of Medicine.

Atraumatic shoulder pain can mean an insidious onset or from a chronic injury (more than six months, but often several years old). Much like the recent recommendations on knee surgery, shoulder decompression surgery should be reserved for acute injuries.

Wednesday, February 6, 2019

Wisdom Wednesday: Heavy Metals Found in Popular Fruit Juices



Nearly half of 45 fruit juices tested had elevated levels of heavy metals, which can pose health risks for children and adults, Consumer Reports has found.

The report, released Wednesday, says that even small amounts of juice might hold risks.
"In some cases, drinking just 4 ounces a day — or half a cup — is enough to raise concern," James Dickerson, PhD, chief scientific officer for CR, says in the report.

If anything, the results simply reinforce existing concerns about fruit juices. "I don't think we need to say you can't give your kids any juice," says Steven Abrams, MD, a professor of pediatrics at Dell Medical School, University of Texas at Austin. But, he says, "juice is not a product that is intrinsically healthy for children." He coauthored the American Academy of Pediatrics' guidelines on juice, which set limits by age. Meanwhile, juice producers say the report needlessly alarms consumers.

Consumer Reports experts tested 45 juices made by 24 brands, including well-known and lesser-known brands such as Gerber, Minute Maid, Mott's, Great Value from Walmart, Clover Valley from Dollar General, and Big Win from Rite Aid. Those tested included organic products, too, as well as store brands from Whole Foods and Trader Joe's.

They focused on levels of cadmium, lead, mercury, and inorganic arsenic, saying that these elements pose some of the greatest risks and that research has found they are common in food and drink. The juices tested were apple, fruit blends, grape, and pear.

The new testing was done as a follow-up to a study in 2011, when CR found elevated levels of inorganic arsenic and lead in apple and grape juices. The new evaluation was done to see if there's been improvement, to test other juices, and to test for other heavy metals.

Overall, CR says, heavy metal levels in fruit juices have declined since their last testing. But in the new report, every juice contained at least one of the four metals tested, and 47%, or 21, had concerning levels of cadmium, inorganic arsenic, and/or lead. None had concerning levels of mercury. Other major conclusions: Seven of the 21 had enough heavy metals to potentially harm children who drink a half-cup or more a day, and nine of the 21 held risks for kids drinking a cup or more a day. Ten of the juices posed a risk to adults, too: Five were potentially hazardous at a half-cup or more a day, and five at a cup or more a day. The highest heavy metal levels were in grape juice and juice blends. Organic juices did not have lower heavy metal levels than non-organic.

Monday, February 4, 2019

Antibiotics disrupt gut bacteria, impact bone health

A new study about the side effects of antibiotic treatment reveals that it may dysregulate post pubertal skeletal development by interfering with gut bacteria.

The trillions of bacteria living in our bodies are crucial for our health. They support the gastrointestinal and immune systems. They also help the body absorb nutrients from foods and supplements. People often call the "good" bacteria within us "commensal," because they live together in harmony without causing any harm. However, we often treat the "bad" microbes that cause disease using antibiotics.

Some researchers from the Medical University of South Carolina (MUSC) in Charleston specialize in osteoimmunology, the "interface of the skeletal and immune systems." The scientists analyzed the impact of antibiotics on post pubertal skeletal development and published their results in The American Journal of Pathology. The study demonstrated that antibiotic disruption of the gut microbiota causes a proinflammatory response that may lead to less bone resorption, a process by which osteoclasts, or large bone cells, release the minerals and transfer them to the blood.

According to Chad M. Novince, Ph.D. — who studies the link between microbiome and skeletal health — the study "introduces antibiotics as a critical exogenous modulator of gut microbiota osteoimmune response during post pubertal skeletal development."

The post pubertal phase of development supports the accumulation of about 40 percent of peak bone mass. Previous research by Novince and team had already shown that the gut
microbiota contributes to skeletal health.

Friday, February 1, 2019

Don’t Succumb to the Common Cold

The winter season may be a time of comfort: a slower pace, inner focus, and reflection, but it is also the time of year that many people will battle against cold and flu season. The viruses that cause cold and flu symptoms, technically respiratory infections, reliably spring to life between November and March in the Northern Hemisphere, with most American adults getting an average of between two to four colds per year. 

While being exposed to cold winter weather won’t necessarily mean you’ll “catch a cold,” transmission rates are highest in cold, dry air. Cold and flu viruses thrive when the temperatures plunge. Research suggests that these viruses are most virulent at temperatures near 40 degrees Fahrenheit or colder, and they do not transmit at all at temperatures around 85 degrees. This may be due to the virus’ outer lipid membrane, which is fortified by cold weather, forming a rubbery gel-like consistency that enables the virus to survive longer outside a host. Once the virus enters the respiratory tract, the outer membrane melts, and the virus is able to infect host cells and replicate.

However, in warmer temperatures, that membrane is more likely to have a liquidly consistency, effectively weakening the virus so that it loses the ability to spread readily between hosts. 

Luckily, there are many ways to reduce the risk for the common cold and flu, as well as strategies to shorten the duration and lessen the severity of any cold or flu infection that does take hold. Time-honored lifestyle strategies that help keep the immune system robust and resilient include: Eating a healthful diet that includes a wide variety of colorful fruits, vegetables, herbs, and spices to help bolster the immune system, getting adequate sleep, exercising daily, managing stress, maintaining healthy vitamin D levels, washing hands often and supplementing with appropriate vitamins, herbs, and other medicinal plants.