Archive for the ‘HIV/AIDS’ Category

Thanks for the Memory: part 2: Dementias

Tuesday, June 19th, 2012

It's on the tip of my tongue

In 1990 I needed neurosurgery. The mass which was removed turned out to be benign, but I had a major post-op bleed and was left with a considerable scar on my right frontal cortex. Up to that point I'd had, as I often said, "the fourth best memory in the family."

Afterwards my brain worked well enough. But I had considerable problems moving information from short-term to long-term memory. So when I bought the Harvard Medical School booklet mentioned in my last post, I was intrigued by the research that has been done on the subject and how it applied to me and to others, especially as we age.

Most of us worry about dementia; the Aging, Demographics and Memory Study figures, published in 2007 looking at people 71 or older, estimated there were 3.9 million people with dementia in the US in 2002. Of that group, 2.4 million had Alzheimer's disease. The crucial factor, I thought, was the prevalence, the total number living with a disease, went up with age from 5% of people in the 71 to 79 year old group to 37.4% in those 90 and above. And there are lots more of us living to that age than before.

It's become clear that having a stroke, what used to be termed a "cerebrovascular accident" (CVA), is another major route for developing dementia. A 2010 study in the journal Stroke describes dementia associated with "first-ever stroke" in a French city of 150,000 inhabitants over a 24-year period. Out of nearly 4,000 patents suffering a CVA, 20.4% had dementia. Risk factors for the outcome included age, diabetes, prior heart attack, and atrial fibrillation (an irregular heart rhythm associated with a risk of emboli, blood clots that can be dislodged, travel to the brain and clog an artery).

These figures clearly included those with new-onset dementia, but, because of the study's design, didn't exclude those who may have had the problem prior to their stroke. Nonetheless a history of stroke nearly doubles the prevalence of dementia in people over 65.

Another group with an increased incidence of neurocognitive (thinking/memory) issues includes the roughly 40 million infected with HIV. At least 30% of that group have associated brain function impairment ranging from minor or mild symptoms to full-fledged dementia. With the newer anti-retroviral drug treatments, the incidence (new cases) of HIV-associated dementia (HAD) has markedly decreased, although with people living longer with the virus, overall there are more HAD patients.

There is a roadblock between the circulation and the brain itself, the blood-brain barrier (BBB), which serves, in usual circumstances, to prevent microbes from invading the central nervous system. The human immunodeficiency virus can penetrate the BBB in several ways: one of which is by hitching a ride inside one kind of immune cells called monocytes. This is termed a "Trojan Horse" method.

Another disease, affecting 1.3 million Americans, is termed Lewy Body Dementia (LBD). It's closely associated with the dementia seen in Parkinson's disease. Both have deposits of an abnormal protein that causes difficulties in brain function. In LBD these proteins are found in several areas of the brain; with Parkinson's they are more localized.

Let's get the right pill to help, not hinder

So why is it important to know what kind of dementia a person has?

Some types respond poorly to medications that may help other forms, at least to a limited extent. And LBD patients may be helped by meds that offer less benefit to Alzheimer patients.

It's not always easy, but an experienced neurologist can often sort out which person has which disease.


Meth Madness: Part 2

Sunday, January 1st, 2012

Users of both genders and all ages abuse this drug

I want to be perfectly clear: methamphetamine use is a terrible plague in our society.  Although overall numbers are down over the past decade, we're still talking about a million plus people in the United States, many of whom are young and heterosexual. But, of course, that's not the only population group with members who abuse the drug; The CDC factsheet on its risk for HIV/AIDS stresses it can contribute to sexual risk behaviors, regardless of the sexual orientation of the user. I spoke recently to a long-term friend who is gay.  I asked him about its use in the gay community and he replied, "Everyone I ever knew about who used meth is dead."

There's a brain chemical called dopamine that affects how we experience pleasurable activities. Lab experiments show this highly addictive and illegal drug can lead to considerably greater dopamine being released than either eating or having sex.

A user experiences a high, a "rush" much more intense than from any normal activity. But there's a problem; it doesn't last more than eight to 24 hours. And it's not as intense in succeeding uses. So that leads to a pattern of addiction, the need for not only repeated  drug use, but more and more of the substance.

Chronic, repeated meth exposure, whether by oral ingestion, 'snorting", smoking or injection, clearly leads to damage in the brain, the teeth and the skin.

An online review by the  National Institute on Drug Abuse, part of the National Institutes of Health, says imaging studies (e.g., MRIs) done on meth addicts show alterations in parts of the brain involved in motor skills, verbal learning, emotion and memory.

I went back to the PBS special, "How Meth Destroys the Body" and was stuck by the graphic photos of "meth mouth." A common sign of abuse of this drug is severe tooth decay. The cause is uncertain, but meth does lead to shrinkage of a user's blood vessels and the mouth requires an adequate blood supply to stay healthy. The addicts often binge on high-sugar foods and drinks; their mouths lack sufficient saliva to maintain optimal healthy oral tissue and, on a high, meth users often grind their teeth and, of course, forget to brush or floss.

Between the tooth decay, the increased physical activity frequently experienced and the failure to eat adequately, meth users lose weight and look older.

the model of meth's structure looks benign; it's not, though!

They also lose interest in any activities other than those related to obtaining and snorting or injecting the drug. Men may become impotent; women may lose their interest in sex.

So why don't we require simply prescriptions for the cold and allergy pills that contain psudoephedrine, the chemical I mentioned in my last post that is used in the production of methamphetamine? I read an article in the 20 December 2011 edition of the Annals of Internal Medicine which told of the widespread abuse of controlled substances in the United States. It wasn't describing illegal drugs, just ones that normally do require a doctor's prescription. Many of these can now be purchased on the Internet.

That series of photos of meth users mouths and "before" and "after" photos of addicts may be one place to start.






Meth Madness: Part 1

Wednesday, December 28th, 2011

Some people just pop pills

Recently our local paper, the Fort Collins Coloradoan, published a USA Today article titled "Missouri grapples with meth." I read about the nearly 7,000 law-enforcement seizures of laboratories and methamphetamine-related material in 2011 (through late November), saw that Colorado wasn't in the top ten states involved (at least in methamphetamine lab seizures) and wondered why Missouri, with 1,744 confiscations, was clearly the hot spot for this drug

A contentious issue is whether state law requires a  doctor's prescriptions for over-the-counter medications containing pseudoephedrine, a chemical also used for meth production. That's not true in Missouri where, at present the rules vary from county to county. Oregon and Mississippi have already passed such laws with impressive declines in meth seizures as a result. Fifteen other states have proposed similar legislation.

Then I found a series of articles that brought this issue squarely home to my state. In April 2011  the Denver Post published  two articles about proposed Colorado legislation that, if passed by the state Senate, would have made a number of pseudoephedrine-containing medications, used to treat the symptoms of colds and allergies, available only by prescription; eventually the potential new law went down to defeat by a 7 to 2 vote.

Yet the Colorado Meth Project, part of a much larger, multi-state prevention program whose focus is reducing the usage of this drug, said my home state ranked 7th in the U.S. in total number of "past-year meth users" aged 12 and up in a national survey on drug use during the 2006 to 2009 time frame. Did the "12 and up" catch your attention? This campaign, named the world's 3rd most effective charitable endeavour by a national magazine, was started in 2005 and works in three arenas: public service messages, public policy and community outreach.

It's been given credit for marked reduction of methamphetamine use in a number of states. As part of an ongoing CDC surveillance system, monitoring six types of health-risk behaviors that contribute to the leading causes of death and disability among youth and adults, the 2010 Youth Risk Behavior Survey saw a highly significant decline of teen meth use: 52% in Idaho, 63% in Montana and 65% in Arizona.

But we're not just speaking about teens. In late November of 2011, a 68-year-old former Colorado county sheriff was arrested; he allegedly was trading meth for gay sex. If proven guilty, he clearly wasn't alone in his drug-related activities.

Others inject their drug of choice

So returning to the question of why is this particular illegal substance so important? It's a highly addictive stimulant responsible for risky sexual behavior and extreme violence. The Centers for Disease Control and Prevention (CDC), published an extensive  2007 review on methamphetamine use and the risk for HIV/Aids. After discussing research indicating that meth-using gay men may increase their risk factors, they mentioned that heterosexual adults and adolescents who use meth may also engage in sexual practices that markedly increase their possibility of developing STDs including HIV.

That's by no means all that methamphetamine does to its users, but I'll write more concerning the chemistry and effects of the drug in my next post.