Alzheimer's Disease Archive

In the journals

Because older adults often experience temporary changes in memory and thinking after having general anesthesia, they may worry that it increases their risk of dementia. A recent study should help put their minds at ease. Researchers found no association between the type of anesthesia and dementia risk, according to findings published online Oct. 6, 2020, by the Journal of the American Geriatrics Society.

The study looked at almost 7,500 people ages 66 or older without diagnosed dementia who underwent surgery requiring either general anesthesia (where you are unconscious) or regional anesthesia (where you are awake and the surgical area is numbed). The researchers included only people who had not had any previous surgery and stopped assessing those who had a second surgery later.

Ask the doctor

Q. I read that the death rate from COVID-19 is going down, but that people who recover from the infection still can remain sick for a long time. Is that true?

A. It is true, but we don't yet know how big the problem is: COVID-19 has been with us for only a year, and there hasn't been enough time to know the long-term effects.

The potential causes may be hard to pin down. Here are some of the most common ones — and what to do about them.

Sometimes it's easy to know why a particular part of your body is itchy. Maybe you have a bug bite, allergies, or a visible skin condition such as eczema. It's harder to know the cause when there's nothing obvious behind all-over, generalized itching. "It's the most common skin complaint in people over age 65," says Dr. Kenneth Arndt, a dermatologist and former medical editor of the Harvard Special Health Report Skin Care and Repair.

Potential causes

Generalized itching has many potential triggers. One is aging. "The skin barrier doesn't work as well as it used to, and things that may not have irritated you before may now be absorbed in the skin and cause itching," Dr. Arndt explains. "The skin also develops a somewhat impaired immune response, a reduction in fat and blood flow, and altered sensory perception, making it more prone to itching."

Experts say that while there are many unknowns about long-term COVID effects, it's hoped that more information will be available soon.

A growing number of Americans have now experienced a bout of COVID-19, and doctors are only just beginning to learn more about the aftereffects of the infection.

"Reports are coming out describing long-term lung effects — which is not surprising, as scarring may occur and cause permanent impairment — and also of neurological, cardio­vascular, and kidney effects," says Dr. David Christiani, a professor of medicine at Harvard Medical School and a pulmonary physician at Massachusetts General Hospital.

Although executive function skills begin to develop in the first year of life, the time at which children reach these milestones varies. Some children experience challenges or delays related to their executive function skills, but these skills can be improved through evidence-based interventions.

If you have chickenpox as a child, the virus stays in your body, and can emerge later in life as a painful, burning rash called shingles. It’s not fully understood what triggers a resurgence of the virus, but factors that weaken the immune system increase the risk of developing shingles, and it is more common in people over age 60.

In the journals

Many commonly used drugs have anticholinergic effects, meaning the drugs block the action of acetylcholine. Nerve cells release acetylcholine to transmit impulses to other nerves in the brain and throughout the body. Previous research has shown a link between these drugs and dementia. Now a study has found a similar link with mild cognitive impairment (MCI), especially if you take larger doses. The findings were published online Sept. 2, 2020, by Neurology.

Some medications are designed purposefully to block acetylcholine, such as those used for urinary incontinence. But more often the anticholinergic action is a side effect of drugs taken to treat conditions like allergies, colds, and depression.

Research we're watching

According to a study published in the Aug. 4, 2020, issue of Neurology, the number of new cases of dementia in Europe and North America has dropped 13% every 10 years over the past 30 years. Researchers looked at data collected by the Alzheimer's Research Consortium, which included people over age 65 in Europe and the United States.

The actual number of adults with dementia has increased dramatically in recent years as life expectancy increases. The condition currently affects some 47 million people worldwide, and that number is expected to increase in coming decades.

Contrary to conventional wisdom, some blood pressure drugs are linked to a lower risk of depression.

Like all medications, blood pressure drugs sometimes cause unwanted side effects. While many are mild and short-lived, some are more worrisome, including mood changes such as depression. But contrary to what doctors have long assumed, blood pressure drugs may not raise the risk of depression. In fact, some appear to be linked to a lower risk, according to a recent study (see "Depression rates in people taking different blood pressure drugs").

"The traditional view has been that blood pressure drugs that cross the blood-brain barrier are more likely to cause depression," says Dr. Randall -Zusman, a cardiologist at Harvard-affiliated Massachusetts General Hospital. Depression has also been associated with drugs known as beta blockers. But beta blockers (which work in part by slowing the heart rate) can also make you feel tired and listless, which may dampen your mood, Dr. Zusman explains.

News briefs

If your doctor or pharmacist offers a service to monitor blood pressure measurements you send from home (called telemonitoring), consider taking advantage of it. Past research has shown that telemonitoring — often paid for by Medicare — may help you reduce your blood pressure. And a study published online Aug. 31, 2020, by Hypertension suggests telemonitoring is also associated with a long-term reduction in heart attacks, strokes, and medical costs. The recent study is a follow-up to a randomized controlled trial from 2013 that divided 450 people into two groups: those who received routine primary care, and those who received a year of telemonitoring services with a pharmacist who helped manage their treatment. People in the telemonitoring group had lower blood pressure for up to two years afterward, compared with people who received routine care. In the recently published follow-up, which followed the same participants for five years, researchers found there were about half as many heart attacks, strokes, and hospitalizations in the telemonitoring group as there were in the group that received routine care. Because there were fewer cardiovascular problems, people in the telemonitoring group also saved an estimated $1,900 each in medical costs.