Workshop Proceedings - AAA Foundation for Traffic Safety

A recent study from Canada noted that patients in a glaucoma clinic in comparison to
controls had an increased risk for motor vehicle crashes in the previous five years and
also an increase in at-fault crashes (Haymes, LeBlance, Nicolela, Chiasson, &
Chauhan, 2007). Of all the baseline visual measures that were used in this study,
Useful Field of View® was most predictive for crashes, but visual field impairment and
stereopsis were also associated with increased at-fault crash risk. While several other
studies have shown increase in crash risk in patients with glaucoma (Hu, Trumble,
Foley, & Eberhard, 1998; Owsley, McGwin, & Ball, 1998; Szlyk, Mahler, Seiple, Deepak,
& Wilensky, 2005), others have not (McGwin, Mays, Joiner, DeCarlo, McNeal & Owsley,
2004; McCloskey, Keopsell, Wolf, & Buchner, 1994). Two crash studies that noted
increased risk, studied patients with moderate to severe disease who have an impaired
visual field of less than 100 degrees total horizontal field (Szlyk et al., 2005) or
impairment in the central 24 degrees radius field in the worse functioning eye (McGwin,
Mays, & Joiner, 2004).
Recent studies have indicated that lowering intraocular pressure decreases the rate of
progression (Heijl, Leske, Bengtsson, Hyman, Bengtsson, & Hussein, 2002; Leske, Hejl,
Hussein, Bengtsson, Hyman, & Komaroff, 2003).Treatment can be either medical (e.g.,
eye drops) or surgical with use of a laser. Eye drops either reduce intraocular pressure
by decreasing aqueous production and/or increasing outflow. Beta-blockers are typically
prescribed to decrease aqueous production (e.g., Betoptic or betaxolol), as are topical
carbonic anhydrase inhibitors (e.g., Trusopt), or combination agents (e.g., Cosopt or
dorzolamide and timolol maleate combination). Topical prostaglandin analogs (e.g.,
latanoprost or Xalatan) are the most common medications that are prescribed for this
condition and decrease aqueous production. Alpha agonists can both increase aqueous
outflow and decrease production and are at times used in combination or as
monotherapy (e.g., Alphagan and brimonidine tartrate).
COGNITION
Cerebrovascular Accident
A cerebrovascular accident (CVA), or stroke, occurs when the blood supply to the brain
in a specific area is diminished or occluded. Strokes are often classified into
ischemic/infarcts or hemorrhagic/bleeds. Stroke is the third leading cause of death in
most industrialized countries, making up 10 percent of all deaths (Leske, Hejl, Hussein,
Bengtsson, Hyman, & Komaroff, 2003). Each year in the U.S., about 500,000 people
experience a first stroke attack and 200,000 experience a recurrent attack. Stroke most
heavily impacts select groups such as African-Americans between the ages of 35 and
65 (American Heart Association, 2004). While fatalities are decreasing, morbidity is
increasing—stroke is the leading cause of serious disability in the U.S. In 1999, more
than 1,100,000 American adults reported functional limitations resulting from stroke.
From 50–70 percent of stroke survivors regain functional independence, but 15–30
percent fails to regain independence, and 20 percent require institutional care at three
months after onset (Thom, 2006). Research on the proportion of working age stroke
survivors who return to work shows mixed findings, with rates from 7 to 84 percent in 20
studies across a number of countries (Lock, Jordan, Bryan, & Maxim, 2005). In 2006,
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