Roundup: CDC Guidance for Those Most Vulnerable to Flu Complications; Heart Valve Infections in Young Adults; and More News

CDC: These Chronic Health Conditions Can Sharply Raise Risk of Serious Flu Illness

As the flu season enters its annual peak (December-February), the U.S. Centers for Disease Control and Prevention (CDC) released guidance this week for those at higher risk of developing potentially serious flu complications that can result in hospitalization or even death. The CDC states that those most vulnerable are people with asthma, heart disease, diabetes, and a number of other chronic health conditions.

“In fact, during recent flu seasons, 9 out of 10 people hospitalized with flu had at least one underlying health condition – that’s why getting an annual flu vaccine is especially important for people with certain chronic health conditions,” the CDC states in the featured topic this week.

Overall, adults 65 years and older are at higher risk of developing serious complications from flu, compared with young, healthy adults. For expectant moms, changes to the immune system, heart, and lungs during pregnancy can make them more susceptible to severe flu, the CDC said.

Here’s what the CDC states about the top chronic health conditions that make a person most vulnerable to the seasonal flu:

Heart Disease and Stroke: Among adults hospitalized with flu during recent flu seasons, heart disease was one of the most common chronic (long-term) conditions—about half of adults hospitalized. Studies have shown that flu illness is associated with an increase in heart attacks and stroke.

Asthma: People with asthma are at higher risk even if their asthma is mild or their symptoms are well-controlled by medication. People with asthma can develop swollen and sensitive airways, and flu can cause further inflammation of the airways and lungs.

Diabetes: In recent seasons, about 30 percent of adults hospitalized with flu reported to CDC had diabetes. The flu can make it harder to control your blood sugar levels. Flu may raise your blood sugar levels, but sometimes people don’t feel like eating when they are sick and a reduced appetite can cause blood sugar levels to fall.

Chronic Kidney Disease (CKD): CKD can weaken a person’s immune system, which can make it tougher to fight infections. People with CKD at any stage, those who have had a kidney transplant, and those who are undergoing dialysis treatment are all at higher risk of severe illness from flu.

Deaths from Rare Heart Valve Infections have Surged in Young Adults, New Study Finds

Death rates linked to infective endocarditis, a rare heart infection, declined in most adults across the U.S. within the last two decades. But the condition has increased among young adults ages 25- to 44-years-old, according to new research published in the Journal of the American Heart Association, a peer-reviewed journal of the American Heart Association.

Infective endocarditis, also called bacterial endocarditis, is an infection caused by bacteria that enter the bloodstream and settle in the lining of the heart, a heart valve or a blood vessel.

The disease is rare, but  people with previous valve surgeries, heart valve abnormalities and artificial valves – most of whom are usually older patients – have a greater risk of developing the condition. Patients with congenital heart defects or previous infective endocarditis also carry a higher risk. But infective endocarditis can also be a complication of injecting illicit drugs.

“Our study findings raise a public health concern, especially since the deaths in younger age groups are on the rise,” said study lead author Sudarshan Balla, M.D., an associate professor of medicine at the West Virginia University Heart and Vascular Institute at J.W. Ruby Memorial Hospital, in a statement “We speculate that this acceleration was likely, in the most part, due to the opioid crisis that has engulfed several states and involved principally younger adults.”

Researchers examined death certificate data from the U.S. Centers for Disease Control and Prevention (CDC). They focused on national trends in deaths caused by infective endocarditis, and differences in deaths related to age, sex, race and geography.

According to a news release from the American Heart Association, the researchers found:

• In the 21-year period reviewed, infective endocarditis death rates declined overall in the U.S.
• Death rates increased significantly for young adults, at an average annual change of more than 5 percent for the 25-34 age group and more than 2 percent for the 35-44 age group.
• In the 45-54 age category, death rates remained stagnant at 0.5 percent, and there was a significant decline among those aged 55 and older.
• Substance use disorder associated with multiple causes of death increased drastically – between 2-fold and 7-fold among the 25-44 age group.

Researchers Identify Key Cause of 'Morning Sickness' in Pregnancy, and Possible Prevention

So-called "morning sickness" -- or nausea and vomiting in pregnancy -- has long been a forgone conclusion for expectant mothers, affecting 80 percent of women at some point during pregnancy.

In a new study, researchers from University of Southern California and University of Cambridge have found that a hormone produced by the fetus, GDF15, and a mother’s sensitivity to the hormone are the causes behind nausea and vomiting during pregnancy.

Extreme cases of such "morning sickness" symptoms can put the mother and fetus at risk. In rare cases, a related condition, hyperemesis gravidarum (HG), can lead to weight loss, dehydration and hospitalization.

The findings, which are published in Nature, suggest that pre-pregnancy exposure to the hormone might help alleviate symptoms in some women.

The new study "supports the causal role of GDF15 in pregnancy sickness and reveals the role a woman’s sensitivity to the hormone has in determining the severity of her symptoms," states a news release.

Women who are more sensitive to the hormone get the sickest, said Professor Sir Stephen O’Rahilly, M.D., co-director of the Wellcome-Medical Research Council Institute of Metabolic Science at the University of Cambridge, who led the collaboration with USC on the study. “Knowing this gives us a clue as to how we might prevent this from happening.”

Lowering GDF15 is one way to potentially reduce pregnancy sickness—and the new study indicates that it is likely safe to do so. Another way to reduce symptoms involves exposing women to GDF15 prior to pregnancy, to “prime” or prepare them for elevated levels of the hormone once they become pregnant, states the news release.

In cases where both the mother and fetus had the low-GDF15 mutation, babies were born normal and healthy. That indicates that lowering GDF15 levels during pregnancy may be another safe way to prevent HG, the study’s authors state.