The Observatory

Nov. 20, 2015

Cancer

Only one in five U.S. pancreatic cancer patients gets key blood test at diagnosis. Only 19 percent of pancreatic cancer patients in the Unites States receive a widely available, inexpensive blood test at diagnosis that can help predict whether they are likely to have a better or worse than average outcome and guide treatment accordingly, a Mayo Clinic study shows. People who test positive for elevated levels of a particular tumor marker tend to do worse than others, but if they are candidates for surgery and have chemotherapy before their operations, this personalized treatment sequence eliminates the elevated biomarker’s negative effect, researchers found.

“This is another argument for giving chemotherapy before surgery in all pancreatic cancer patients and ending the old practice of surgery followed by chemo,” says senior author Mark Truty, MD. “The study answers an important clinical question and applies to every pancreatic cancer patient being considered for surgery.”

Researchers analyzed outcomes for 97,000 patients. The tumor marker whose impact they studied is known as CA 19-9. It is associated with several cancers, including pancreatic cancer, and can be measured in the blood of most people: 10 percent do not produce it. Pancreatic cancer patients who didn’t secrete CA 19-9 were also studied.

Pancreatic cancer patients whose blood showed higher-than-normal CA 19-9 levels tended to have worse outcomes than others at the same stage of cancer, the study found. Failing to test for and address elevated CA 19-9 means that many patients with above-normal levels may undergo significant surgeries that may not be as beneficial long-term as anticipated, Truty says.

Infectious Disease

WHO estimates two-thirds of the population under 50 are infected with herpes simplex virus type 1. More than 3.7 billion people under the age of 50, or 67 percent of the population, are infected with herpes simplex virus type 1 (HSV-1), according to the World Health Organization’s (WHO) first global estimates of HSV-1 infection, published in the journal PLOS ONE.

Herpes simplex virus is categorized into two types: herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2). Both HSV-1 and HSV-2 are highly infectious and incurable. HSV-1 is primarily transmitted by oral-oral contact and in most cases causes orolabial herpes or “cold sores” around the mouth. HSV-2 is almost entirely sexually transmitted through skin-to-skin contact, causing genital herpes.

The new estimates highlight, however, that HSV-1 is also an important cause of genital herpes. Some 140 million people aged 15 to 49 years are infected with genital HSV-1 infection, primarily in the Americas, Europe, and the Western Pacific. Fewer people in high-income countries are becoming infected with HSV-1 as children, likely due to better hygiene and living conditions, and are instead at risk of contracting it through oral sex after they become sexually active.

New Studies

Death rates, health problems, rise among middle-aged white Americans. Deaths among white men and women ages 45 to 54 in the United States rose significantly between 1999 and 2013, according to a new analysis. This change reversed decades of progress in mortality and was unique to non-Hispanic whites in the United States. The study found self-reported declines in health, mental health, and abilities to conduct activities of daily living, accompanied by increases in reports of chronic pain, inability to work, and deterioration of liver function among this group.

Anne Case, PhD, and Angus Deaton, PhD, of Princeton University detail these findings in a study funded by the National Institute on Aging, part of the National Institutes of Health.

The three causes of death that accounted for the change in mortality among non-Hispanic whites were suicide, drug and alcohol poisoning, and chronic liver diseases and cirrhosis. The researchers used data from the Centers for Disease Control and Prevention (CDC), the U.S. Census Bureau, individual death records, and other sources for their analysis.

From 1978-1998, the mortality rate for middle-aged white Americans fell by an average of two percent per year. This matched the average rate of decline in most other developed nations. Those countries continued to see declines of about two percent per year after 1998. The mortality rate for middle-aged people in the United States began to increase by half a percent a year, starting in 1999.

The authors note that the increase in midlife mortality is only partly understood. Increased availability of opioid prescription drugs, chronic pain (for which opioids are often prescribed), and the economic crisis which began in 2008 may all have contributed to an increase in overdoses, suicide, and increased liver disease associated with alcohol abuse.

Diabetes

Task Force recommends screening of all overweight or obese adults for abnormal blood sugar. The U.S. Preventive Services Task Force (USPSTF) recommends screening overweight and obese adults between the ages of 40 and 70 for abnormal blood sugar. Patients found to have high blood sugar should be referred to intensive behavioral counseling interventions for a healthy diet and exercise.

Type 2 diabetes has risen in prevalence over the past 15 years. In 2012, 12 percent of American adults had diabetes and 37 percent had abnormal blood sugar levels that put them at increased risk for developing diabetes. Abnormal blood sugar levels occur when the body does not consistently break down and use sugar, but the condition is not yet severe enough to be classified as type 2 diabetes.

This is an update of the 2008 USPSTF recommendation statement in which the USPSTF recommended screening for  iabetes in asymptomatic adults with hypertension. At that time, the USPSTF found insufficient evidence to assess the balance of benefits and harms of screening in adults without hypertension. Since the previous recommendation, six new lifestyle intervention studies have shown consistent benefit of lifestyle modifications to prevent or delay progression to diabetes, and longer-term follow-up has increased confidence that such interventions can improve clinical outcomes. This new body of evidence led the USPSTF to conclude that there is moderate net benefit to measuring blood glucose in adults who are at increased risk for diabetes.

Genetics/Genomics

NIH researchers link single gene variation to obesity. A single variation in the gene for brain-derived neurotropic factor (BDNF) may influence obesity in children and adults, according to a new study funded by the National Institutes of Health. The study suggests that a less common version of the BDNF gene may predispose people to obesity by producing lower levels of BDNF protein, a regulator of appetite, in the brain. The authors propose that boosting BDNF protein levels may offer a therapeutic strategy for people with the genetic variation, which tends to occur more frequently in African Americans and Hispanics.

The BDNF protein plays several roles in the brain and nervous system and, at high levels, the protein can stimulate the feeling of fullness. The study team, led by Joan C. Han, MD, first analyzed the BDNF gene for naturally occurring genetic changes that alter levels of BDNF production.