Wednesday, January 30, 2019

Wisdom Wednesday: Gut Microbiota and the Neuroendocrine System


The gut-brain axis is undeniable, but specific mechanisms of influence continue to be investigated. Specifically, the gut microbiota is now considered the body’s major neuroendocrine system, controlling body processes including the stress response and the hypothalamic-pituitary-adrenal (HPA) axis.

Back in the early 20th century, Nobel laureate, Ilya Metchnikoff, observed that the growth of cholera could be reduced by some microbes and enhanced by others. He proposed that commensal bacteria within the intestine could contribute to protection against this pathogen and alteration of the gut bacteria could prevent disease. In 2001, Nobel Prize winner Joshua Lederberg coined the term “microbiome”. The microbiome is the “ecological community of commensal, symbiotic and pathogenic microorganisms” that can be found on mucosal surfaces, including the eye, mouth, lungs, and the gut. Recent research reviews the connection between the microbiota and the neuroendocrine system.

The article is a review of the literature showing the connection of the microbiome to remyelination, microglia function, diseases like multiple sclerosis (MS), recovery from spinal cord injury and even behavior. The article cites research that links MS with intestinal permeability. Other research shows a link between the microbiome and pediatric MS, suggesting a connection between myelin production and metabolites produced by gut microbes (particularly p-cresol). Short chain fatty acids from the bowel flora (especially butyrate) affect remyelination, microglia function, and also oligodendrocyte differentiation. In the autoimmune disease, neuromyelitis optica, research shows there may be a connection to bowel ecology. Another study showed the connection between CNS inflammation and the gut microbiome in mice.

Monday, January 28, 2019

Quercetin

Quercetin is a pigment found in many plants, fruits, and vegetables. It may have some health benefits and help prevent a range of conditions. People can get quercetin through a balanced diet or by taking a supplement. Quercetin is a flavonol, which is a sub-category of flavonoids. Flavonoids are a particular chemical in plants, called phytonutrients, and have a wide range of health benefits. Humans cannot make quercetin in their body, but many fruits, vegetables, and drinks contain it. Foods and drinks that contain quercetin include: grapes, berries, cherries, apples, citrus fruits, onions, buckwheat, broccoli, kale, tomatoes, red wine and black tea.

Quercetin is also present in herbal remedies, such as ginkgo biloba and St John's wort. People can also take quercetin as a supplement. Quercetin is a more powerful antioxidant than vitamin C, vitamin E, or beta carotene. Quercetin might help reduce inflammation. One study on animals found that quercetin prevented both acute and chronic inflammation, in addition to showing anti-arthritis properties. Quercetin may contain anticancer properties that might help prevent the spread of cancerous cells and tumor growth. Quercetin may help to prevent neurodegenerative diseases, such as Alzheimer's or Parkinson’s disease.

Research suggests that quercetin might be an effective antihistamine, as it restricts histamine from being released from cells. These anti-allergy properties indicate that quercetin might help treat bronchitis and asthma. Quercetin has antibacterial properties, which are effective against almost all types of bacteria. Quercetin may improve blood vessel cell health and blood flow through arteries in people with heart disease. According to a 2016 study by the American Heart and Stroke Association, taking quercetin supplements could be an effective way to reduce blood pressure.

Friday, January 25, 2019

Climate Change — A Health Emergency

In this issue of the Journal, Haines and Ebi summarize the devastating effects that the global burning of fossil fuels is having on our planet (pages 263–273). Disruption of our climate system, once a theoretical concern, is now occurring in plain view — with a growing human toll brought by powerful storms, flooding, droughts, wildfires, and rising numbers of insectborne diseases. Psychological stress, political instability, forced migration, and conflict are other unsettling consequences. In addition, particulate air pollutants released by burning fossil fuels are shortening human life in many regions of the world. These effects of climate disruption are fundamentally health issues, and they pose existential risks to all of us. People who are sick or poor will suffer the most.

As physicians, we have a special responsibility to safeguard health and alleviate suffering. Working to rapidly curtail greenhouse gas emissions is now essential to our healing mission. The United Nations Intergovernmental Panel on Climate Change concluded that we need to cut global greenhouse gas emissions in half by 2030 and entirely by 2040 to avoid the most catastrophic effects of climate change. Yet these emissions hit a record high in 2018. Rapid but equitable changes in energy, transportation, and other economic sectors are needed if we are even to begin to meet the requisite emissions-reduction targets. Tackling this challenge may feel overwhelming, but physicians are well placed and, we believe, morally bound to take a lead role in confronting climate change with the urgency that it demands.

Individual lifestyle actions (e.g., walking or cycling rather than driving, eating less meat, reducing food waste, and conserving energy) are the easiest for us to undertake, offer many benefits for personal wellness, and allow us to model health-promoting behaviors as we reduce our environmental footprint. But individual actions are far from enough to address the challenge we collectively face. The financial interests of organizations vested in the fossil fuel industry, a federal administration that disavows climate science and its own responsibility to act, and inertia are powerful countervailing forces. Changing our institutions and society will therefore require concerted, organized, and forceful efforts.

Wednesday, January 23, 2019

25% of Antibiotic Prescriptions Could Be Inappropriate


At least a quarter of outpatient antibiotic prescriptions filled in 2016 may have been unnecessary, researchers conclude in The BMJ.

Using a national U.S. claims database, the researchers identified over 15 million outpatient antibiotic prescriptions filled in 2016 by privately insured children and adults under age 65. The most common antibiotics used were azithromycin, amoxicillin, and amoxicillin-clavulanate, accounting for roughly half of prescriptions.

On the basis of ICD-10-CM diagnosis codes:
23% of prescriptions were classified as inappropriate, usually for acute bronchitis, acute upper respiratory tract infection, or respiratory symptoms.

36% were potentially appropriate, most frequently for acute sinusitis, acute suppurative otitis media, or acute pharyngitis.

13% were considered appropriate, most often for urinary tract infections, streptococcal pharyngitis or tonsillitis, and bacterial pneumonia.

Some 29% of antibiotic prescriptions did not have an associated diagnosis code.

Monday, January 21, 2019

CDC Offers Update on Flu Activity This Season

The CDC on Friday offered its weekly snapshot of influenza activity so far this season. Among the findings for the week ending January 12:
Influenza A(H1N1)pdm09 viruses have predominated in most regions, although influenza A(H3) viruses have been most common in the Southeast.
Most circulating viruses are genetically similar to the reference viruses used for this year's flu vaccines.

All tested viruses have been susceptible to neuraminidase inhibitors (oseltamivir, zanamivir, and peramivir). Information on susceptibility to the newly approved flu drug, baloxavir, will be available later in the season.

New York City and 22 states had either high or moderate influenza activity.

The CDC also estimated that between 6.2 and 7.3 million people in the U.S. had symptomatic influenza from October 1, 2018, through January 5, 2019. This led to some 2.9 to 3.5 million medical visits and 69,300 to 83,500 hospitalizations. The agency noted that this is the first time it's reported in-season estimates, so the numbers can't be used to evaluate how this season compares with prior seasons.

My Take:
There was no data on the estimated number of related deaths given by the CDC. All the vaccines noted are administered through a shot. There was no data on the nasal vaccine.

Friday, January 18, 2019

Key West Sunscreen Ban?

The Key West City Commission on Tuesday unanimously voted to ban the sale of sunscreens that contain two ingredients — oxybenzone and octinoxate — that a growing body of scientific evidence says harm coral reefs. “This ordinance is just one other thing we can do to help improve and protect our water quality,” said Mill McCleary, of the nonprofit environmental protection group Reef Relief.

The measure, which passed 7-0, isn’t law yet, though. The commission must review it a second time and pass the measure again before it would become law. The second vote is scheduled for Feb. 5.

Environmental researchers have published studies showing how these two ingredients, which accumulate in the water from bathers or from wastewater discharges, can damage coral reefs through bleaching and harming the corals’ DNA. In some instances, the corals can die.
Last year, Hawaii banned the sale or distribution of any sunscreens containing oxybenzone and octinoxate, a measure that will go into effect on Jan. 1, 2021. It was the first state in the nation to implement such a ban.

In Florida, the website for the South Florida Reef Ambassador Initiative, which falls under the state’s Department of Environmental Protection, tells divers to “Avoid sunscreens with Oxybenzone and Avobenzone. The benzones are compounds that are lethal to coral reproduction in very small amounts.”

Wednesday, January 16, 2019

Wisdom Wednesday: Chronic Pain Syndrome


Chronic pain syndrome (CPS) is a common problem that presents a major challenge to health-care providers because of its complex natural history, unclear etiology, and poor response to therapy. CPS is a poorly defined condition. Most authors consider ongoing pain lasting longer than 6 months as diagnostic, and others have used 3 months as the minimum criterion. In chronic pain, the duration parameter is used arbitrarily. Some authors suggest that any pain that persists longer than the reasonably expected healing time for the involved tissues should be considered chronic pain. Approximately 35% of Americans have some element of chronic pain, and approximately 50 million Americans are disabled partially or totally due to chronic pain. Chronic pain is reported more commonly in women.

CPS can affect patients in various ways. Major effects in the patient's life are depressed mood, poor-quality or nonrestorative sleep, fatigue, reduced activity and libido, excessive use of drugs and alcohol, dependent behavior, and disability out of proportion with impairment. Chronic pain may lead to prolonged physical suffering, marital or family problems, loss of employment, and various adverse medical reactions from long-term therapy. Parental chronic pain increases the risk of internalizing symptoms, including anxiety and depression, in adolescents.

The pathophysiology of chronic pain syndrome (CPS) is multifactorial and complex and still is poorly understood. Some authors have suggested that CPS might be a learned behavioral syndrome that begins with a noxious stimulus that causes pain. This pain behavior then is rewarded externally or internally. Thus, this pain behavior is reinforced, and then it occurs without any noxious stimulus.

A literature review by Gupta et al indicated that in chronic pain patients, primary sensorimotor structural and functional changes are more prominent in females than in males. Males and females differed with regard to the nature and degree of insula changes (with males showing greater insula reactivity), as well as in the extent of anterior cingulate structural changes and in reactivity to emotional arousal.

Monday, January 14, 2019

Can Exercise Lower High Blood Pressure as Effectively as Drugs?

According to the Centers for Disease Control and Prevention (CDC), approximately 75 million adults in the United States have to manage high blood pressure, where it exceeds the threshold of 140 millimeters of mercury (mm Hg). The condition can increase their risk of developing heart disease or experiencing a stroke, both of which are leading causes of death in the U.S. Moreover, high blood pressure drives an expense of around $48.6 billion per year nationally, including the cost of medication, accessed health care, and absence from work.

People with high blood pressure typically follow an antihypertensive or blood pressure-lowering treatment, which includes special medication. At the same time, specialists sometimes advise that people make lifestyle changes to help them manage their blood pressure. One such change is to take regular, structured exercise.

However, no studies have yet compared the effectiveness of physical activity in lowering blood pressure with that of antihypertensive medication. A new study in the British Journal of Sports Medicine — a BMJ publication — aims to address this gap in the literature.
In the current study, they looked at the data from 194 clinical trials that focused on antihypertensive drugs and their impact on systolic blood pressure, and another 197 clinical trials, looking at the effect of structured exercise on blood pressure measurements. In total, these trials collected information from 39,742 participants.

They found that antihypertensive drugs were more effective in lowering blood pressure than structured exercise in the case of the general population. However, when they looked specifically at people with high blood pressure, they saw that exercise was as effective as most blood-lowering medication. Moreover, the study authors concluded that there is "compelling evidence that combining endurance and dynamic resistance training was effective in reducing [systolic blood pressure]."

Friday, January 11, 2019

Are Infectious Complications Following Probiotics an Underestimated Problem?

Probiotics seem to be everywhere. From dietary supplements to chocolate bars, these products are designed to improve one’s microbiome. Yet, there have been few serious evaluations of complications related to probiotic ingestion. This study presents a synthesis and critical evaluation of the reports and series of cases on the infectious complications related to the ingestion of probiotics, which can raise awareness for the prescribing and use of probiotics for certain groups of patients. The researchers emphasize that this study is not meant to discourage the use of probiotics, but to instead better understand that certain high-risk patients may not benefit from the introduction of probiotics in a clinical setting.

In this study, published in BMC Complementary and Alternative Medicine, researchers culled and systematically reviewed the data from PubMed, SciELO and Scopus databases published until August 2018. They found 60 case reports and 7 case series, making up a total of 93 patients. Among those studies, they found certain strains of probiotics were responsible for the most complications. They also found common factors associated with mortality, including infants and the elderly with compromised immunity and the prevalence of C. dificile, colitis and antibiotic use.

The authors note “to assume that probiotic intake is completely risk-free is not true. The proportion of cases of infectious complications is small when the total number of people who use probiotics is considered. However, the cases described here are infections with high mortality rates such as endocarditis and sepsis. So, although on one hand there is the possibility of publication bias, with more serious cases having been published, on the other, due to the mentioned limitation for the publication of case reports, several other serious cases may not have reached public knowledge.”

The use of probiotics cannot be considered risk-free and should be carefully evaluated for some patient groups. The most frequent probiotic-related infectious complications were fungemia and sepsis and the most frequent probiotic microorganisms were of the genus Saccharomyces, a fungus. Mortality was associated with age > 60 years, C. dificile colitis, current antimicrobial use and Saccharomyces infection. Probiotics were often used in the context of excessive antibiotic use, and a more judicious use of antibiotics is critical, as the use of probiotics cannot be considered risk free and should be carefully evaluated for high-risk groups of patients.

Wednesday, January 9, 2019

Wisdom Wednesday: Headaches Attributed to Trauma to the Head or Neck


Headache attributed to trauma or injury to the head and/or neck are among the most common secondary headache disorders. During the first 3 months from onset they are considered acute; if they continue beyond that period they are designated persistent. This time period is consistent with ICHD-II diagnostic criteria, although the term persistent has been adopted in place of chronic.

There are no specific headache features known to distinguish the Headache attributed to trauma or injury to the head and/or neck from other headache disorders; most often these resemble Tension-type headache or Migraine. Consequently their diagnosis is largely dependent upon the close temporal relation between the trauma or injury and headache onset. Consistently the diagnostic criteria of ICHD-3 for all types of Headache attributed to trauma or injury to the head and/or neck require that headache must be reported to have developed within 7 days following trauma or injury, or within 7 days after regaining consciousness and/or within 7 days after recovering the ability to sense and report pain. Although this 7-day interval is somewhat arbitrary, and some experts argue that headache may develop after a longer interval in a minority of patients, there is not enough evidence at this time to change this requirement.

Headache may occur as an isolated symptom following trauma or injury or as one of a constellation of symptoms, commonly including dizziness, fatigue, reduced ability to concentrate, psychomotor slowing, mild memory problems, insomnia, anxiety, personality changes and irritability. When several of these symptoms follow head injury, the patient may be considered to have a post-concussion syndrome.

The pathogenesis of Headache attributed to trauma or injury to the head and/or neck is often unclear. Numerous factors that may contribute to its development include, but are not limited to, axonal injury, alterations in cerebral metabolism, neuroinflammation, alterations in cerebral haemodynamics, underlying genetic predisposition, psychopathology and a patient’s expectations of developing headache after head injury. Recent research, using advanced neuroimaging modalities, suggests a potential for detecting brain structural, functional and metabolic abnormalities following minor trauma that are not detectable through conventional diagnostic tests. Post-traumatic sleep disturbances, mood disturbances and psychosocial and other stressors can plausibly influence the development and perpetuation of headache. The overuse of abortive headache medications may contribute to the persistence of headache after head injury through the development of Medication-overuse headache. Clinicians must consider this possibility whenever a post-traumatic headache persists beyond the initial post-trauma phase.

Monday, January 7, 2019

Artificial Sweetners

Objective:
To assess the association between intake of non-sugar sweeteners (NSS) and important health outcomes in generally healthy or overweight/obese adults and children.

Design:
Systematic review following standard Cochrane review methodology.
Data sources Medline (Ovid), Embase, Cochrane CENTRAL, WHO International Clinical Trials Registry Platform, Clinicaltrials.gov, and reference lists of relevant publications.

Eligibility criteria for selecting studies:
Studies including generally healthy adults or children with or without overweight or obesity were eligible. Included study designs allowed for a direct comparison of no intake or lower intake of NSS with higher NSS intake. NSSs had to be clearly named, the dose had to be within the acceptable daily intake, and the intervention duration had to be at least seven days.

Main outcome measures:
Body weight or body mass index, glycaemic control, oral health, eating behaviour, preference for sweet taste, cancer, cardiovascular disease, kidney disease, mood, behaviour, neurocognition, and adverse effects.

Results:
The search resulted in 13 941 unique records. Of 56 individual studies that provided data for this review, 35 were observational studies. In adults, evidence of very low and low certainty from a limited number of small studies indicated a small beneficial effect of NSSs on body mass index (mean difference −0.6, 95% confidence interval −1.19 to −0.01; two studies, n=174) and fasting blood glucose (−0.16 mmol/L, −0.26 to −0.06; two, n=52). Lower doses of NSSs were associated with lower weight gain (−0.09 kg, −0.13 to −0.05; one, n=17 934) compared with higher doses of NSSs (very low certainty of evidence). For all other outcomes, no differences were detected between the use and non-use of NSSs, or between different doses of NSSs. No evidence of any effect of NSSs was seen on overweight or obese adults or children actively trying to lose weight (very low to moderate certainty). In children, a smaller increase in body mass index z score was observed with NSS intake compared with sugar intake (−0.15, −0.17 to −0.12; two, n=528, moderate certainty of evidence), but no significant differences were observed in body weight (−0.60 kg, −1.33 to 0.14; two, n=467, low certainty of evidence), or between different doses of NSSs (very low to moderate certainty).

Conclusions:
Most health outcomes did not seem to have differences between the NSS exposed and unexposed groups. Of the few studies identified for each outcome, most had few participants, were of short duration, and their methodological and reporting quality was limited; therefore, confidence in the reported results is limited. Future studies should assess the effects of NSSs with an appropriate intervention duration. Detailed descriptions of interventions, comparators, and outcomes should be included in all reports.

Friday, January 4, 2019

Does magnesium hold the key to vitamin D benefits?

Vitamin D, also known as the sunshine vitamin, has enjoyed something of a celebrity status, receiving praise for a multitude of health benefits. Yet, in the complex web of biological processes that govern our health, few players ever work in isolation. New evidence shifts the focus onto magnesium, implicating it in playing a central role in determining how much vitamin D our bodies can make.

In a study that features in the December issue of The American Journal of Clinical Nutrition, a research team from Vanderbilt University Medical Center in Nashville, TN concludes that optimal levels of magnesium may play an important role in the vitamin D status of an individual.

Dr. Qi Dai, a professor of medicine at Vanderbilt University Medical Center and the lead study author, previously reported on the relationship between magnesium intake and vitamin D levels in over 12,000 individuals taking part in the National Health and Nutrition Examination Survey (NHANES) 2001–2006 study.

Here, Dr. Dai and team found that individuals with high levels of magnesium intake, whether from dietary sources or taking supplements, were less likely to have low levels of vitamin D. Importantly, the researchers also found a possible association between magnesium intake and a reduction in mortality, particularly when they looked at mortality due to cardiovascular disease and bowel cancer.

So, how does magnesium affect vitamin D biology in the body? It is a cofactor in the synthesis of vitamin D from both exposure to sunlight and dietary sources. "Magnesium deficiency shuts down the vitamin D synthesis and metabolism pathway," Dr. Dai explains.