Combination of Severe Depression and Antidepressant Use Impairs Driving Ability

[Halo]

Combination of Severe Depression and Antidepressant Use Impairs Driving Ability

August 19, 2008 (Boston, Massachusetts) ? A combination of severe depression and antidepressant use may impair driving ability, new research suggests.

In a study presented here at the American Psychological Association 116th Annual Convention, researchers from the University of North Dakota found individuals with severe depression who were taking antidepressants had reduced concentration and slower reaction times behind the wheel than their counterparts with milder depression who were also taking antidepressants.

Furthermore, study participants with mild depression who were taking antidepressants performed no differently from normal controls.

"These findings suggest that together, high depression scores and antidepressant use seem to confer a double whammy, so that individuals with this combination have significantly poorer concentration and slower reaction times when driving," principal investigator Holly Dannewitz, PhD, told Medscape Psychiatry.

Conflicting Findings

According to Dr. Dannewitz, a small number of previous studies suggest some antidepressants can negatively affect individuals' cognitive performance, impairing memory and reducing reaction time. However, she added, other studies suggest antidepressant treatment has no effect on cognitive function.

To further explore the potential impact of these medications on cognitive function, and specifically driving performance, the researchers recruited 60 individuals ? 31 who were on at least 1 antidepressant and 29 matched controls who were taking no medication with the exception, in some cases, of oral contraceptives.

To determine depression levels and information about current medication use, all participants completed the Beck Depression Inventory, 2nd ed (BDI-II), a History of Sadness Questionnaire, and a medical history questionnaire.

Subjects in the antidepressant group were further divided into 2 groups, 1 with average BDI-II scores of 0 ? 12 and the other with above-average BDI-II scores of 14 ? 39.

Study subjects participated in a computerized driving simulation to assess driving ability ? specifically, steering, scanning, and concentration. Following completion of practice laps, individuals completed 4 test laps. The practice lap was the easiest and the final lap the most difficult in terms of a greater number of distracters and the need for more responses.

The driving simulator measured reaction times for 2 tasks ? a peripheral and central task. The central task required subjects to hit the brake pedal in response to brake lights, while the peripheral task required participants to hit a paddle in response to a stop sign or traffic signal.

Driving Ban Not Warranted

Interestingly, said Dr. Dannewitz, there were no differences between any of the study groups in terms of their steering/tracking ability. However, the more "subtle" measures of reaction time were where individuals with high depression scores performed poorly.

Although patients with high depression scores who used antidepressant medications did worse than the other 2 study groups, Dr. Dannewitz said the impairment is not so severe that it would warrant a driving ban in such individuals.

Nevertheless, she said, physicians with patients who fit this profile should be aware that their driving ability and other functions that require optimal concentration and quick reaction time may be impaired.

Further research is warranted to tease out whether mood or medication use is the primary driver of this phenomenon or whether there may be a synergistic effect at play. It would also be useful, she said, to investigate different types of antidepressants to uncover potential differences between classes of antidepressant mediations or individual drugs.

American Psychological Association 116th Annual Convention: Abstract I-11. Presented August 17, 2008.

 

[Into The Light]

i didn't read this thoroughly but i think just severe depression impairs a person. i remember crossing a street and forgetting to even look if traffic was coming my way. that was without being on medication. i remember driving too and having a near miss.

with severe depression you are so sleep deprived and so exhausted.

i'm not convinced that the anti-depressants are the culprit here.

 

[Halo]

From what I understand, the article is saying that the culprit is antidepressants alone but yet that the combination of severe depression together with antidepressants could impair driving ability.

It is not the antidepressants only as indicated by this:

Furthermore, study participants with mild depression who were taking antidepressants performed no differently from normal controls.

 

[Daniel E.]

There were no differences between any of the study groups in terms of their steering/tracking ability. However, the more "subtle" measures of reaction time were where individuals with high depression scores performed poorly.

I wonder if there is a do-it-yourself test for reaction time like playing a racing video game at home

From an older article that Halo posted last year:

Patients taking SSRIs and mirtazapine had better test performance than those who were taking tricyclics.

Antidepressants' Effects on Driving Ability - Psychlinks Psychology Self-Help & Mental Health Support Forum

 

[Halo]

I guess the bottom line on both articles ends up the same:

Antidepressants' Effects on Driving Ability -- The researchers urged clinicians to stress to patients who are taking antidepressants the possible effects of their medication while driving.

and

Combination of Severe Depression and Antidepressant Use Impairs Driving Ability -- Nevertheless, she said, physicians with patients who fit this profile should be aware that their driving ability and other functions that require optimal concentration and quick reaction time may be impaired.

 

[ladylore]

I know that taking Amatriptyline makes me drowsy. I take it at night but there are lasting effects throughout the day.

 

[Into The Light]

but no one seems to be comparing mild depression with severe depression where people are not on any medication.

severe depression in and of itself impairs people's abilities and reaction time.

or is that so obvious it's not looked at?

 

[Daniel E.]

Yeah, an article I saw at FOX News (and probably most articles about this study) also failed to discuss that point.

I just went to the APA convention's website, and their press release is certainly the source of the confusion. Fortunately, they also link to a US News article that shows some good journalism:

Antidepressant Use Tied to Poorer Driving

But experts aren't sure if the pills, or underlying depression, are to blame

August 17, 2008
By Alan Mozes
HealthDay Reporter

SUNDAY, Aug. 17 (HealthDay News) -- Taking prescription antidepressants while still highly depressed could impair driving ability, a new study suggests.

"We already know that depression causes concentration problems," said study author Holly J. Dannewitz. "And now it appears that people taking antidepressants who also have relatively higher depression scores fare significantly worse when attempting to perform a computerized simulation of driving."

Dannewitz conducted her research while a graduate student at the University of North Dakota in Grand Forks, where she is currently a psychology resident in a private practice.

She and her colleagues were scheduled to present their findings Sunday the American Psychological Association annual meeting, in Boston.

To gauge the possible impact antidepressants might have on driving performance, the research team asked 60 people to "drive" a computerized version of a car in a program that mimicked real-world conditions.

Approximately half of the participants were taking at least one type of antidepressant, while the other half was taking no medication (other than oral contraceptives in certain instances). Those on antidepressants were screened for current levels of depression and were subsequently categorized as experiencing either low or high depression at the time of the driving test.

Participants had to perform common driving tasks such as braking, steering, and scanning sightlines in response to an unfolding video of car traffic, stop signs, speed limit signs, traffic lights, deer crossings, bicyclists, and even the appearance of helicopters.

People taking antidepressants who were highly depressed registered markedly worse scores on some driving skills than those not taking antidepressants, the team found. This appeared tied to poorer concentration and a weakened ability to react well to situations that divided their attention and relied on memory skills.

These deficits weren't found among those who were taking antidepressants but had low depression scores. In fact, that group was found to execute their driving tasks with a precision equal to that of those not on medication.

Dannewitz said that her future work would involve patients who are diagnosed with clinical depression but not on antidepressants. In this way, her team can determine whether it's the depression, or medications used to treat it, that are at the root of the concentration problems.

"More research needs to be done, of course," she said. "And I wouldn't want to instill fear in drivers. But I think that perhaps individuals who are taking these medications should just be aware of the fact that they may cause concentration problems and impair reaction time."

Dannewitz also stressed that, "this issue is not just a question for drivers, because the cognitive skills needed for driving are also needed for a lot of other skills."

Dr. Bernard Carroll, scientific director of the Pacific Behavioral Research Foundation based in Carmel, California, agreed that it's too early to draw specific conclusions from the study. But he said the findings weren't surprising.

"There is already a very deep literature about subtle impairments of higher cognitive function associated with clinical depression itself, apart from medications," he noted. "I would add that, in any case, medication package inserts routinely warn patients about a whole host of issues when starting a course of psychotropic drugs, including warning against the handling of machinery, driving, or engaging in any occupation in which you can be injured. So, to that extent, this concern isn't new."

Antidepressant Use Tied to Poorer Driving - US News and World Report

BTW, from Florida's driver safety handbook (which is required reading for obtaining a Florida driver's license):

Emotions can have a great effect on you driving safely. You may not be able to drive well if you are overly worried, excited, afraid, angry or depressed.

If you are angry or excited, give yourself time to cool off. If necessary take a short walk, but stay off the road until you have calmed down.

If you are worried, down or upset about something, try to keep your mind on driving. Some find listening to the radio helps.

If you are impatient, give yourself extra time for your driving trip. Leave a few minutes early. If you have plenty of time, you may not tend to speed or do other thing that can get you a traffic ticket or cause a crash. Don't be impatient to wait for a train to cross in front of you. Driving around lowered gates or trying to beat the train can be fatal.

State of Florida.com - Florida Driving Priveleges

I never thought listening to the radio could actually help, but I'm sure it is true in some cases, though in other cases it could be distracting in a bad way.

 

[Halo]

severe depression in and of itself impairs people's abilities and reaction time.

:agree:

or is that so obvious it's not looked at?

Probably and I think that the use of medication was the focus point of the research more than the level of depression. Although the article that Daniel posted does indicate that a slightly different perception but clearer view, in my opinion.