Monday, June 11, 2018

‘Millions’ Prescribed Wrong Dose of Common Drugs

According to updated calculations published this week, over 11 million people in the United States may have been given the wrong prescription for a range of commonly used drugs.

Scientists from the Stanford University School of Medicine in California recently investigated the reliability of so-called pooled cohort equations (PCEs). PCEs help doctors to determine each patient’s overall risk of stroke or heart attack. Assessing cardiovascular risk helps to inform the physician about the exact level of medication that will be both effective and safe. These equations are available as online web tools and smartphone apps, and they are even built into digital medical records.

In recent years, some have called into question the accuracy of PCEs, asking whether the data that they rely on are outdated. If this were found to be the case, patients could potentially be at risk of taking dangerously high or ineffectively low doses of drugs.

Dr. Sanjay Basu, Ph.D., an assistant professor of primary care outcomes research at Stanford published his findings this week in the journal Annals of Internal Medicine.

The first issue was updating the data used to derive the equations. Some of the datasets are relatively old. For instance, one included information from people who were aged 30-62 in 1948. Diet, lifestyle and health risks have changed since those days. The study authors say that, because of the age of this information, people’s risks were being estimated at around 20% higher than they truly were. Dr. Basu notes that “relying on our grandparents’ data to make our treatment choices is probably not the best idea.”

“Another issue the researchers identified was the lack of African-Americans in the datasets. It is now known that cardiovascular risk is significantly higher in the African-American population. So, while many Americans were being recommended aggressive treatments that they may not have needed according to current guidelines, some Americans – particularly African-Americans – may have been give false reassurance and probably need to start treatment given our findings.” – Dr. Sanjay Basu, Ph.D.

Friday, June 8, 2018

Is Chemo for Breast Cancer overprescribed?

According to a landmark study, a large percentage of individuals with the most common form of early breast cancer could safely skip chemotherapy. The findings could impact thousands of people each year.

While new therapies such as immunotherapies are becoming increasingly crucial in treating cancer, chemotherapy is still a mainstay. Though chemotherapy is effective, it carries with it a range of significant side effects, such as hair loss, increased risk of bleeding, susceptibility to infection, nausea, vomiting, and anemia. Consequently, chemotherapy is only used when deemed entirely necessary. The challenge lies in determining exactly when it is entirely necessary.

Individuals with breast cancer sometimes have their tumors analyzed using a gene test called the Oncotype DX test. This examines how active 21 specific genes are provides a “recurrence score” of 0-100. When scores are high, chemotherapy will be used following surgery or radiation therapy to lower the risk of the cancer returning. For individuals with low scores, the tumors are considered less dangerous, and chemotherapy is not deemed essential.

This type of testing has proven useful but there is a substantial gray area. As it stands, those who score 1-10 do not receive chemotherapy and those who score above 25 do. The majority of women, however, fall in the intermediate range of 11-25.

To get a better picture of who needs treatment, researchers from Loyola Medicine and Montefiore Medical Center undertook a large-scale investigation. Their findings are now published in the New England Journal of Medicine.

They used data from more than 10,000 women with hormone-receptor-positive, HER-2 negative breast cancer – the most common form of breast cancer, accounting for about half of breast cancer cases in the United States. Of particular interest were the 69% of women who had scored 11-25 on the 21-gene test.

Wednesday, June 6, 2018

Wisdom Wednesday: Plant Pigments May Preserve Lung Function into Old Age

New research finds that flavonoids – which are natural chemical compounds found in plants, such as fruits and vegetables – can help to slow the decline in lung function that tends to occur with age.
As the plants’ pigments, flavonoids are responsible for the vibrant colors of fruits and vegetables. They also attract pollinating insets and regulate cell growth. Research has suggested that dietary flavonoids may hold a lot of benefits for human health.

In vivo and in vitro studies have exposed flavonoids’ range of anti-inflammatory and antidiabetic properties, as well as their anticancer and neuroprotective benefits. New research adds to this list, suggesting that a certain type of flavonoid called “anthocyanins” can help to maintain healthy lung function well into old age.

The research was led by Vanessa Garcia-Larsen, Ph.D., who is an assistant professor in the Human Nutrition Division of the Department of International Health at the Johns Hopkins Bloomberg School of Public Health in Baltimore, MD. The findings were presented at the American Thoracic Society International Conference, held in San Diego, CA.

For this study, the researchers looked at data available from 463 adults from Norway and England – aged 44, on average – who took part in a spirometry test at the beginning of the study and at different follow-up times.

Spirometry is a pulmonary lung function test that measures the airflow and the volume of air that a person can exhale on command.

Additionally, the study participants had filled in a dietary questionnaire, so the researchers were able to divide the participants into quartiles, or fourths, based on their dietary intake of anthocyanins.
The research revealed that the highest quartile of anthocyanin consumers, when compared with the lowest, had a much slower rate of decline in all three aspects of lung function measured by the spirometry.

Monday, June 4, 2018

Pesticides May Cause Parkinson’s in Some People

New research reveals how the pesticides paraquat and maneb alter gene expression and may lead to Parkinson’s disease in people who are genetically predisposed to the illness.

Estimates show that around 50,000 people in the United States are diagnosed with Parkinson’s disease every year. Although it is not exactly known what causes the disease, both genetic and environmental factors are thought to play a critical role.

Senior study author Scott Ryan, a professor of molecular and cellular biology at the University of Guelph in Ontario, Canada explains the motivation behind the research. He notes, “People exposed to these chemicals are at about a 250% higher risk of developing Parkinson’s disease than the rest of the population.”

The findings were published in the journal Federation of American Societies for Experimental Biology.

The researchers used stem cells from patients with Parkinson’s disease who had a mutation in the gene responsible for encoding the a-synuclein protein. At least 30 alterations in this gene have been associated with Parkinson’s, and a-synuclein protein clumps are a well-documented, albeit poorly understood, hallmark of the disease. The scientists also worked with normal embryonic cells that they modified using genetic editing to replicate the a-synuclein genetic mutation.

Prof. Ryan explains why using human cells makes this study particularly valuable. “Until now,” he says, “the link between pesticides and Parkinson’s disease was based primarily on animal studies as well as epidemiological research that demonstrated an increased risk among farmers and others exposed to agricultural chemicals.” “We are one of the first to investigate what is happening inside human cells,” he explained.

It was found that the neurons that had been exposed to the chemical had faulty mitochondria. Mitochondria, the “powerhouses of the cell,” are the organelles inside a cell that turn sugar, fats, and proteins in to the energy our body needs to survive and function.

Friday, June 1, 2018

Shoulder Subluxation

Shoulder subluxation refers to a partial dislocation of the shoulder joint. This occurs when the ball of the upper arm bone, called the humerus, partly comes out of the glenoid socket in the shoulder.

The shoulder is the most mobile joint in the body. It contains several bones, ligaments, and muscles that work together to keep it stable. Because the shoulder is so mobile, it is very susceptible to dislocation. Shoulder subluxation is often the result of trauma, injury or a stroke that weakens the arm muscles.

Symptoms of a shoulder subluxation can include a visibly deformed or out-of-place shoulder, pain, swelling, numbness or tingling or trouble moving the joint. A person may be able to feel the ball of the humerus moving in and out of the shoulder socket. They may also notice a clicking or catching sensation especially when reaching overhead.

Treatment aims to reposition the humerus back into the socket and ensure that it stays in place. Treatment options include: 1. Closed reduction involves a doctor attempting to gently maneuver the bone back into position. When this is achieved, severe pain should improve almost immediately. 2. Surgery may be recommended when dislocations recur or when nerves, blood vessels, or ligament in the shoulder have been damaged. 3. A splint, brace, or sling for a few days or weeks to prevent the shoulder from moving. The length of time will depend on the extent of the dislocation. 4. A muscle relaxant and an anti-inflammatory agent, such as ibuprofen, for pain and swelling. 5. Rehabilitation following surgery or time spent in a sling.

When a person seeks medical attention promptly and receives a correct diagnosis, shoulder subluxation is treatable. When no surgery is recommended, several months may pass before a person call tell how well the treatment is working.

Monday, May 28, 2018

Ulnar Tunnel Syndrome

Ulnar tunnel syndrome occurs when the ulnar nerve in the wrist becomes compressed by a cyst or repeated strain. The nerve compression can cause numbness or tingling in the hands or fingers, burning pain, muscle weakness in the hand, difficulty gripping with the fingers and thumb, and fingers bending into a claw shape.

The ulnar nerve runs from the neck down to the hand. At the wrist, the lunar nerve enters the hand though Guyon’s canal. If the nerve becomes compressed here, it causes ulnar tunnel syndrome. Compression of this nerve at the elbow is called cubital tunnel syndrome. Ulnar tunnel syndrome is less common than cubital tunnel syndrome and carpal tunnel syndrome.

Development of a ganglion cyst in the wrist is a common cause of ulnar tunnel syndrome but anything which places pressure on the ulnar nerve in the wrist can be a cause. The risk of developing ulnar tunnel syndrome is greater if a person has had a previous injury to the wrist, performs repetitive tasks with the hands, does activities or sports that put the wrist under strain or uses vibrating tools.

Diagnosis is typically made by medical history and physical exam. However, a physician may also suggest imaging studies (x-ray, CT scan, and/or MRI), electromyography, and/or nerve conduction study.

Monday, May 21, 2018

Acute Ischemic Stroke and High-Risk TIA

Combination antiplatelet therapy with clopidogrel and aspirin may reduce the rate of recurrent stroke during the first 3 months after a minor ischemic stroke or transient ischemic attack (TIA). A trial of combination antiplatelet therapy in a Chinese population has shown a reduction in the risk of recurrent stroke. We tested this combination in an international population.

A total of 4881 patients were enrolled at 269 international sites. The trial was halted after 84% of the anticipated number of patients had been enrolled because the data and safety monitoring board had determined that the combination of clopidogrel and aspirin was associated with both a lower risk of major ischemic events and a higher risk of major hemorrhage than aspirin alone at 90 days. Major ischemic events occurred in 121 of 2432 patients receiving clopidogrel plus aspirin and in 160 of 2449 patients receiving aspirin plus a placebo, with most events occurring during the first week after the initial event. Major hemorrhage occurred in 23 patients receiving clopidogrel plus aspirin and 10 patients receiving aspirin plus placebo.

In summary, patients with minor ischemic stroke or high-risk TIA, those who received a combination of clopidogrel and aspirin had a lower risk of major ischemic events but a higher risk of major hemorrhage at 90 days than those who received aspirin alone.

My Take:
The accompanying editorial points out that most of the benefit of this combination therapy is during the first week following a minor stroke or TIA. Limiting the use of both drugs to three weeks was recommended.

The use of aspirin as secondary prevention (after an ischemic event) is well established as a medical standard. However, the common practice of taking an aspirin daily as primary prevention is not. Several studies have demonstrated that the side effects of daily aspirin, including major hemorrhage and death, exceed any benefit in preventing an initial event. Again, the odds favor the use of aspirin after a patient has suffered a heart attack, stroke, or TIA.

The Bottom Line:
If you are taking an aspirin daily, even a low-dose or “baby” aspirin for primary prevention, please review this practice with your primary care physician. It is not the standard of care. If you have had a vascular event and are taking a daily aspirin with another blood thinner (combination therapy), like this study, please review this practice with your health care provider. Although still an accepted practice, the long term risks involved outweigh the benefits.

Source: May 16, 2018 New England Journal of Medicine