In identifying a new type brain disorder, Dr. James Parkinson
described his first patient as a humble gardener who led a life
of "remarkable temperance and sobriety." Such personality traits, as
well as the doctor's name, are now synonymous with a condition that
affects more than 1.5 million Americans.
Since Parkinson's was discovered, doctors have noticed that a number
of people who go on to develop the disease tend to be cautious,
morally resolute and uninterested in seeking out new experiences.
Indeed, some studies suggest that smokers or alcohol drinkers are at
a lower risk for Parkinson's.

But with the advent of powerful new treatments, researchers have
seen a Jekyll and Hyde personality emerge as well. In study after
study, patients who are treated for Parkinson's sometimes exhibit a
range of unsettling characteristics, such as gambling, overeating
and obsessive compulsive disorders. They may also abuse their
medications and even make inappropriate sexual advances.

Overall, these types of behavior are rare. Only about five percent
of patients treated for Parkinson's exhibit such impulse control
problems. But these changes can be quite serious, especially if they
lead to addiction or sexual harassment.


"There are different levels of severity." says Dr. Matthew Menza, a
professor of psychiatry and neurology at the Robert Wood Johnson
Medical School in New Jersey.

Some personality changes can be relatively harmless, such as
starting to buy lottery tickets, as one of Menza's patients did. As
long as this doesn't break the bank, there is little reason to alter
treatment, he says. Others, however, may experience a much more
dramatic transformation.

"You sometimes see very aggressive sexual impulses." says
Menza. "This can be so out of character with what that person has
ever done before."

The Wrong Kind of Reward
Such an odd shift in behavior, while not fully understood, seems to
be based on the amount of dopamine circulating in the brain. This
chemical is believed to act as a natural reward mechanism, helping
to control how we define pleasure.

When dopamine is at a normal level, there is less of a need to seek
outside stimulation. But when the chemical is out of kilter,
researchers have found the people are prone to all kinds of vices,
from obsessive eating to becoming addicted to drugs.

Parkinson's patients, who gradually lose dopamine because of the
disease, have a natural aversion to these types of sensations, Menza
says. This can quickly change when a person is given a dopamine-
boosting drug.

"The same would probably be true for anyone who tried them." says
Menza.

Those who need these medications face a range of problems. This past
fall, a team from the Mayo Clinic found that Parkinson's patients
who have never seriously gambled before were all of a sudden losing
thousands of dollars at a casino after starting treatment. More
recently, a team at Columbia University found that several of their
patients had trouble resisting the urge to eat when taking
Parkinson's medications, causing them to gain significant weight.

Treatment may be only part of the issue. Compared to 100 patients
who used Parkinson's drugs without becoming addicted to them, those
who abused their medications were more likely to be younger, drink
alcohol, suffer from depression and exhibit more novelty-seeking
traits to begin with, a new study from England found.

Attacking the Cause
So what should patients do? First off, experts say, is to recognize
such problems exist. Although surgery and a variety of Parkinson's
drugs have been linked to these side effects, the major culprit
appears to be the so-called dopamine agonists, such as Requip and
Mirapex, which are more potent than other medications. These drugs
are favored by younger patients because they have a lower risk of
long term complications than Sinemet, the mainstay of Parkinson's
treatment.

Reducing the doses may help, but this raises the risk of
uncontrolled tremors, says Menza. Dr. Daniel Weintraub, a professor
of psychiatry and neurology at the University of Pennsylvania
Medical School, says that the simple answer is to switch from a
dopamine agonist to another medication.

For those who experience behavioral changes with treatment, various
interventions are known to improve impulse control and fight
addiction. Anti-psychotic medications can also help keep such
troubling behavior in check. Ultimately, it's up to the patient to
recognize that they are not acting like the person they've always
been.

"When patients are taken off these drugs, they return to normal."
says Weintraub.


By: Eric Sabo