New research on hearing aid use, nuts
Also: A promising skin patch for vaccines, cancer medications
October 1, 2019
Microneedle patches in development
Researchers now have come up with a skin patch that could potentially painlessly deliver vaccines and cancer medications in one minute. Nearly 100,000 new cases of melanoma are diagnosed annually, and 20 Americans die every day from it. Now, researchers have developed a skin patch that efficiently delivers medication within one minute to attack melanoma cells. The device, which has been tested in mice and human skin samples, could be adapted to deliver a host of medicines and vaccines.
Topical ointments can impart medications to the skin, but they can only penetrate a small distance through it. While syringes are an effective drug delivery mode, they can be painful. Microneedle patches, prepared with a layer-by-layer coating method, are one easy, pain-free way to administer treatment. Paula T. Hammond, PhD, along with her colleagues at the Massachusetts Institute of Technology (MIT), Boston, Massachusetts, vaccinated mice with their patches, and compared the results with intramuscular and subcutaneous injections. The microneedle treatment produced nine times the antibody level compared to intramuscular injections, such as those used for flu shots, and 160 times the antibody level compared to subcutaneous injections, such as those used for the measles vaccines. They also saw efficient immune activation in surgical samples of human skin.
“Our patch technology could be used to deliver vaccines to combat different infectious diseases,” said Hammond. “But we are excited by the possibility that the patch is another tool in the oncologists’ arsenal against cancer, specifically melanoma.” To make a melanoma vaccine, the researchers developed an antigen that includes a marker frequently overexpressed by melanoma cells, as well as an adjuvant, which creates a generalized danger signal for the immune system and boosts its response.
Eating nuts may produce a hidden health benefit
Eating nuts at least twice a week appears to be associated with a 17% lower risk of death from cardiovascular disease, according to a new study out of Iran. Researchers examined the association between nut consumption and the risk of cardiovascular disease and death in the Iranian population. A total of 5,432 adults aged 35 and older with no history of cardiovascular disease were randomly selected from urban and rural areas of the Isfahan, Arak and Najafabad counties. Intake of nuts including walnuts, almonds, pistachios, hazelnuts and seeds was assessed in 2001 with a validated food frequency questionnaire.
“Nuts are a good source of unsaturated fat and contain little saturated fat,” said study author Dr. Noushin Mohammadifard of Isfahan Cardiovascular Research Institute, Iran. “They also have protein, minerals, vitamins, fiber, phytosterols, and polyphenols, which benefit heart health. European and U.S. studies have related nuts with cardiovascular protection but there is limited evidence from the Eastern Mediterranean Region.”
Participants or family members were interviewed every two years until 2013 for the occurrence of cardiovascular events and death. The specific outcomes investigated were coronary heart disease, stroke, total cardiovascular disease, death from any cause, and death from cardiovascular disease. During a median 12-year follow-up, there were 751 cardiovascular events (594 coronary heart disease and 157 stroke), 179 cardiovascular deaths, and 458 all-cause deaths.
Eating nuts two or more times per week was associated with a 17% lower risk of cardiovascular mortality compared to consuming nuts once every two weeks. The connection was robust even after adjusting for factors that could influence the relationship such as age, sex, education, smoking, and physical activity.
“Raw fresh nuts are the healthiest,” added Dr Mohammadifard. Some nutritionists advocate eating up to 2 ounces of nuts on most days of the week.
What did you say? I can’t hear you
Older adults who need to get hearing aids but refuse may be making a much more costly mistake than they realize. A new study has found that those with significant hearing loss but don’t get a hearing aid have a higher risk of being diagnosed with dementia, depression and anxiety as well as suffering fall-related injuries.
Only 12% of those who have a formal diagnosis of hearing loss actually get the devices even when they have insurance coverage for at least part of the cost, the study showed. It also revealed gaps in hearing aid use among people of different racial and ethnic backgrounds. Investigators at the University of Michigan analyzed data from nearly 115,000 people over age 66 with hearing loss and insurance coverage through a Medicare HMO between 2008 and 2016. They looked at the data for each person with hearing loss one year before their diagnosis, and three years after, so they could see only newly diagnosed dementia, depression, anxiety and fall injuries.
The study showed that men with hearing loss were more likely to receive a hearing aid than women (13.3% versus 11.3%). Only 6.5% of people of Latino heritage received a hearing aid for their hearing loss, compared with 9.8% of African-Americans and 13.6% of whites.
Lead study investigator Elham Mahmoudi, MBA, PhD, who is with the U-M Department of Family Medicine, said the study confirms what other studies have shown among patients studied at a single point in time, but the new findings show differences emerging as time goes on.
“We already know that people with hearing loss have more adverse health events, and more co-existing conditions, but this study allows us to see the effects of an intervention and look for associations between hearing aids and health outcomes,” said Mahmoudi. “Though hearing aids can’t be said to prevent these conditions, a delay in the onset of dementia, depression and anxiety, and the risk of serious falls, could be significant both for the patient and for the costs to the Medicare system.”
When the researchers looked at the path that patients who received hearing aids took over three years, compared with those who didn’t get the devices, significant differences emerged. In all, the relative risk of being diagnosed with dementia, including
Alzheimer’s disease, within three years of a hearing loss diagnosis was 18% lower for hearing aid users.
The risk of being diagnosed with depression or anxiety by the end of three years was 11% lower for hearing aid users, and the risk of being treated for fall-related injuries was 13% lower.
The reasons for this are complicated, and can include loss of social interaction, loss of independence, loss of balance and less stimulation to the brain. Some researchers also believe that the loss of nerve impulses from the ear to the brain, and loss of cognitive ability leading to dementia, could be part of the same aging process.
John Schieszer is an award-winning national journalist and radio and podcast broadcaster of The Medical Minute. He can be reached at firstname.lastname@example.org.