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Monthly Archives: February 2017

Global Warming May Pose Health Risks

Medical and public health groups are banding together to explain how global warming has taken a toll on human health and will continue to cause food-borne illnesses, respiratory problems, and deaths unless policy changes are enacted.

In a conference call with reporters, the heads of the American Medical Association (AMA) and the American Public Health Association (APHA) joined with a pediatrician and a scientist to lay out what they say is a major public health issue: climate change caused by global warming.

The “evidence has only grown stronger” that climate change is responsible for an increasing number of health ills, including asthma, diarrheal disease, and even deaths from extreme weather such as heat waves, said Dr. Georges Benjamin, executive director of the APHA.

For one, rising temperatures can mean more smog, which makes children with asthma sicker, explained pediatrician Dr. Perry Sheffield, assistant professor in the Department of Pediatrics and the Department of Preventive Medicine at the Mount Sinai School of Medicine, in New York.

There is also evidence that pollen season is also getting longer, she said, which could lead to an increase in the number of people with asthma.

Climate change also is thought to lead to increased concentrations of ozone, a pollutant formed on clear, cloudless days. Ozone is a lung irritant which can affect asthmatics, those with chronic obstructive pulmonary disease, and those with heart disease, said Dr. Kristie Ebi, who is a member of the Intergovernmental Panel on Climate Change.

More ozone can mean more health problems and more hospital visits, she said.

Aside from air-related ailments and illnesses, extreme weather can have a devastating effect on health, Sheffield said.

“As a result of global warming, extreme storms including hurricanes, heavy rainfall, and even snowstorms are expected to increase,” Sheffield said. “And these events pose risk of injury and disruption of special medical services, which are particularly important to children with special medical needs.”

Extreme heat waves and droughts are responsible for more deaths than any other weather-related event, Sheffield said.

The 2006 heat wave that spread through most of the U.S. and Canada saw temperatures that topped 100 degrees. In all, 450 people died, 16,000 visited the emergency room, and 1,000 were hospitalized, said Dr. Cecil Wilson, president of the AMA.

Climate change has already caused temperatures to rise and precipitation to increase, which, in turn, can cause diseases carried by tics, mosquitoes, and other animals to spread past their normal geographical range, explained Ebi.

For instance, Lyme disease is increasing in some areas, she said, including in Canada, where scientists are tracking the spread of Lyme disease north.

Ebi also recounted the 2004 outbreak of the leading seafood-related cause of gastroenteritis, Vibrio parahaemolyticus, from Alaskan seafood, which was attributed to increased ocean temperatures causing infected sea creatures to travel 600 miles north.

Salmonella outbreaks also increase when temperatures are very warm, Sheffield said.

A 2008 study also projected that global warming will lead to a possible increase in the prevalence of kidney stones due to increased dehydration, although the link hasn’t been proven.

Wilson said the AMA wants to make doctors aware of the projected rise in climate-related illnesses. To combat climate change, Wilson says physicians and public health groups can advocate for policies that improve public health, and should also serve as role models by adopting environmentally-friendly policies such as eliminating paper waste and using energy-efficient lighting in their practices.

“Climate instability threatens our health and life-supporting system, and the risk to our health and well-being will continue to mount unless we all do our part to stabilize the climate and protect the nation’s health,” said Wilson.

Benjamin added that doctors should pay attention to the Air Quality Index. For instance, if there’s a “Code Red” day, which indicates the air is unhealthy, physicians should advise patients (particularly those with cardiac or respiratory conditions) that it’s not the day to try and mow the grass.

“ER docs are quite aware of Code Red days because we know that when those occur, we’re going to see lots of patients in the emergency room,” Benjamin said.

The conference call came as Congress is considering what role the Environmental Protection Agency (EPA) should have in updating its safeguards against carbon dioxide and other pollutants.

While the EPA has the authority to regulate levels of CO2, a budget bill passed by the House of Representatives last the weekend prohibited the EPA from exercising that authority. Meanwhile, other bills are pending in Congress that would significantly delay the agency’s ability to regulate air pollutants.

AMA has a number of policies on the books regarding climate change, including a resolution supporting the EPA’s authority to regulate the control of greenhouse gases, and a statement endorsing findings from the most recent Intergovernmental Panel on Climate Change report that concludes the Earth is undergoing adverse climate changes, and that humans are a significant contributor to the changing weather.

In that statement, the AMA said it supports educating the medical community about climate change and its health implications through medical education on topics such as “population displacement, heat waves and drought, flooding, infectious and vector-borne diseases, and potable water supplies.”

The statement also said the AMA supports physician involvement in policymaking to “search for novel, comprehensive, and economically sensitive approaches to mitigating climate change to protect the health of the public.”

Cell Phones Affect Brain Activity

Holding a cell phone to your ear for a long period of time increases activity in parts of the brain close to the antenna, researchers have found.

Glucose metabolism — that’s a measurement of how the brain uses energy — in these areas increased significantly when the phone was turned on and muted, compared with when it was off, Dr. Nora Volkow, director of the National Institute on Drug Abuse, and colleagues reported in the Journal of the American Medical Association.

“Although we cannot determine the clinical significance, our results give evidence that the human brain is sensitive to the effects of radiofrequency-electromagnetic fields from acute cell phone exposures,” co-author Dr. Gene-Jack Wang of Brookhaven National Laboratory in Long Island, where the study was conducted, told MedPage Today.

Although the study can’t draw conclusions about long-term implications, other researchers are calling the findings significant.

“Clearly there is an acute effect, and the important question is whether this acute effect is associated with events that may be damaging to the brain or predispose to the development of future problems such as cancer as suggested by recent epidemiological studies,” Dr. Santosh Kesari, director of neuro-oncology at the University of California San Diego, said in an e-mail to MedPage Today and ABC News.

There have been many population-based studies evaluating the potential links between brain cancer and cellphone use, and the results have often been inconsistent or inconclusive.

Most recently, the anticipated Interphone study was interpreted as “implausible” because some of its statistics revealed a significant protective effect for cell phone use. On the other hand, the most intense users had an increased risk of glioma — but the researchers called their level of use “unrealistic.”

But few researchers have looked at the actual physiological effects that radiofrequency and electromagnetic fields from the devices can have on brain tissue. Some have shown that blood flow can be increased in specific brain regions during cell phone use, but there’s been little work on effects at the level of the brain’s neurons.

So Dr. Volkow and colleagues conducted a crossover study at Brookhaven National Laboratory, enrolling 47 patients who had one cell phone placed on each ear while they lay in a PET scanner for 50 minutes.

The researchers scanned patients’ brain glucose metabolism twice — once with the right cell phone turned on but muted, and once with both phones turned off.

There was no difference in whole-brain metabolism whether the phone was on or off.

But glucose metabolism in the regions closest to the antenna — the orbitofrontal cortex and the temporal pole — was significantly higher when the phone was turned on.

Further analyses confirmed that the regions expected to have the greatest absorption of radiofrequency and electromagnetic fields from cell phone use were indeed the ones that showed the larger increases in glucose metabolism.

“Even though the radio frequencies that are emitted from current cell phone technologies are very weak, they are able to activate the human brain to have an effect,” Dr. Volkow said in a JAMA video report.

The effects on neuronal activity could be due to changes in neurotransmitter release, cell membrane permeability, cell excitability, or calcium efflux.

It’s also been theorized that heat from cell phones can contribute to functional brain changes, but that is probably less likely to be the case, the researchers said.

Dr. Wang noted that the implications remain unclear — “further studies are needed to assess if the effects we observed could have potential long-term consequences,” he said — but the researchers have not yet devised a follow-up study.

“The take-home message,” Dr. Kesair said, “is that we still don’t know, more studies are needed, and in the meantime users should try to use headsets and reduce cell phone use if at all possible. Restricting cell phone use in young children certainly is not unreasonable.”

Exercise and Talk Help Ease Chronic Fatigue Syndrome

Patients with chronic fatigue syndrome who participated in programs aimed at helping them overcome their symptoms — a combination of exercise and counseling— improved more than those whose treatment was intended to help them adapt to the limitations of the disease, a large randomized trial found.

Mean fatigue scores among patients treated with graded exercise therapy — a tailored program that gradually increases exercise capacity — were 3.2 points lower than scores in patients who received specialist medical care alone, according to Dr. Peter D. White, of Queen Mary University of London, and colleagues.

Furthermore, fatigue scores were lower by 3.4 points among patients receiving cognitive behavioral therapy, in which a therapist works with the patient to understand the disease, alleviate fears about activity, and help overcome obstacles to functioning.

In contrast, among patients who were treated with a program known as adaptive pacing therapy, which emphasizes energy limitations and avoidance of excess activity, scores differed by only 0.7 points the researchers reported online in The Lancet.

In a press briefing describing the study findings, co-investigator Dr. Trudie Chalder, of King’s College London, said, “We monitored safety very carefully, because we wanted to be sure we weren’t causing harm to any patients.”

“The number of serious adverse events was miniscule,” she added.

Another co-investigator, Dr. Michael Sharpe, of the University of Edinburgh, commented that a difficulty in the management of chronic fatigue syndrome has been ambiguity — about the causes and whether these treatments recommended by NICE actually are effective.

“The evidence up to now has suggested benefit, but this study gives pretty clear-cut evidence of safety and efficacy. So I hope that addresses the ambiguity,” Sharpe said during the press briefing.

However, the investigators conceded that the beneficial effects of these treatments were only moderate, with less than one-third of participants being within normal ranges for fatigue and functioning, and only about 40 percent reporting that their overall health was much better or very much better.

“Our finding that studied treatments were only moderately effective also suggests research into more effective treatments is needed,” they wrote.

In addition, they stated that their finding of efficacy for cognitive behavioral therapy “does not imply that the condition is psychological in nature.”

The importance of cognitive behavioral therapy was further emphasized by Dr. Benjamin H. Natelson, of Albert Einstein College of Medicine in New York.

“This approach of encouragement of activity and discouragement of negative thinking should be a tool in every physician’s armamentarium,” he said.

“We know that cognitive behavioral therapy and gentle physical conditioning help people cope with any chronic disease — even congestive heart failure and multiple sclerosis,” Natelson said in an interview with MedPage Today.

Chronic fatigue syndrome is characterized by persisting or relapsing fatigue for at least six months that cannot be explained by any other physical or psychiatric disorder.

The fatigue is debilitating, and often is accompanied by joint and muscle pain, headaches, and tenderness of the lymph nodes.

In an editorial published with the study, Dr. Gijs Bleijenberg, and Dr. Hans Knoop, of Radboud University in Nijmegen, the Netherlands, explained the differences in these types of treatment for chronic fatigue.

“Both graded exercise therapy and cognitive behavior therapy assume that recovery from chronic fatigue syndrome is possible and convey this hope more or less explicitly to patients. Adaptive pacing therapy emphasizes that chronic fatigue syndrome is a chronic condition, to which the patient has to adapt,” Bleijenberg and Knoop wrote.

Graded exercise therapy and cognitive behavioral therapy have both been recommended by the U.K. National Institute for Health and Clinical Excellence, although evidence supporting these approaches remains sparse.

Some patient groups have expressed strong disagreement with these recommendations, arguing that cognitive behavioral and graded exercise therapies actually have caused harm to some patients.

These groups advocate exercise pacing and specialist medical care, according to the investigators.

To address this controversy, White and colleagues conducted the largest trial thus far of treatment for chronic fatigue, enrolling 641 patients from six U.K. specialty clinics.

Patients were randomized to receive specialist medical care alone, or specialist medical care plus cognitive behavioral therapy, graded exercise therapy, or adaptive pacing therapy for 24 weeks.

More than three-quarters were women, average age 38, and most had been diagnosed with chronic fatigue syndrome almost three years before entering the study.

At week 52, these percentages of patients improved by at least two points on the fatigue scale and by eight points or more on a physical function scale:

  • Cognitive behavioral therapy, 59 percent
  • Graded exercise therapy, 61 percent
  • Adaptive pacing therapy, 42 percent
  • Specialist medical care, 45 percent

The investigators also looked at percentages of patients who were in the normal range for fatigue and functioning at 52 weeks:

  • Cognitive behavioral therapy, 30 percent
  • Graded exercise therapy, 28 percent
  • Adaptive pacing therapy, 16 percent
  • Specialist medical care, 15 percent

Better outcomes also were seen for cognitive behavioral therapy and graded exercise therapy in a number of secondary outcomes such as social adjustment and sleep disturbances.

Serious adverse events were seen in 2 percent of patients in the cognitive behavioral therapy group, and in 1percent of each of the other three groups.

White’s group acknowledged that the trial had certain limitations, including the exclusion of patients unable to attend the therapy sessions, self-rating by participants, and the unblinded structure of the study.

They plan further study of factors such as cost-effectiveness of the treatments, possible differences in response among subgroups of patients, and long-term outcomes.

Chemical Found in Blood Holds

Even within the normal range, higher bilirubin levels appear to be associated with reduced risks of lung cancer, chronic obstructive pulmonary disease (COPD), and death, a longitudinal, prospective analysis of a large database showed.

For every 0.1-mg/dL increase in bilirubin level, the rate of lung cancer dropped by 8 percent in men and 11 percent in women, according to Laura Horsfall, MSc, of University College London, and colleagues.

In addition, the same incremental increase in bilirubin was associated with a 6 percent decline in the rate of COPD and a 3 percent decline in mortality for both sexes, the researchers reported in the Feb. 16 issue of the Journal of the American Medical Association.

“Based on our findings, bilirubin levels within the normal range appear to capture information about patients that may reflect a combination of environmental and genetically determined susceptibility to respiratory diseases,” they wrote.

Most people are familiar with bilirubin because of its role in jaundice — the yellowing of the skin that is sometimes seen in newborns but is also associated with liver disease.

Bilirubin is actually a byproduct of the turn over of red blood cells — the cells that carry oxygen throughout the body. Healthy individuals constantly replace old red blood cells with new ones. As the old cells are broken down they produce bilirubin, a chemical characterized by a distinctive yellow color.

The spleen and the liver taking in bilirubin and use it to break down or metabolize other substances into bile, which is used to aid digestion.

Although the study cannot establish causality for any of the relationships, there is some experimental evidence that bilirubin has benefits for respiratory health because of its cytoprotective properties, including antioxidant, anti-inflammatory, and antiproliferative effects, according to the researchers.

They noted that a better understanding of the possible mechanisms linking bilirubin levels to lung cancer, COPD, and death may lead to potential therapies that target the activity of UGT1A1, a liver enzyme responsible for converting insoluble bilirubin to an excretable form.

Horsfall and her colleagues examined data from the Health Improvement Network, a U.K. primary care research database.

Their analysis included 504,206 patients ages 20 and older from 371 practices. All of the patients had recorded serum bilirubin levels but no evidence of hepatobiliary or hemolytic disease.

Median bilirubin levels were 0.64 mg/dL in men and 0.53 mg/dL in women.

Through a median follow-up of eight years, there were 1,341 incident cases of lung cancer, 5,863 incident cases of COPD, and 23,103 all-cause deaths. The corresponding rates per 10,000 person-years were 2.5, 11.9, and 42.5.

For men, the rate of lung cancer per 10,000 person-years dropped from 5.0 in the lowest decile of bilirubin levels to 3.0 in the fifth decile. Similar declines were seen for COPD (19.5 to 14.4) and death (51.3 to 38.1).

The findings were similar for all outcomes in women, and the declines in both sexes remained significant after adjustment for age, body mass index, systolic blood pressure, smoking, alcohol intake, and a measure of social deprivation.

The authors acknowledged some limitations of the study, including possible residual confounding by unmeasured environmental exposures or race/ethnicity and the inability to establish causality for the observed relationships.