Emory University Study: IIH, African Americans and Vision Loss
Emory University Study Finds That African Americans with IIH Have a Higher Risk of Vision Loss
April 15, 2008—African Americans are more likely to lose vision as a result of idiopathic intracranial hypertension, according to a study published in a recent issue of the medical journal, Neurology.
“The racial difference does not appear to be based on differences in diagnosis, treatment or access to care,“said study author Beau Bruce, M.D., of Emory University School of Medicine in Atlanta, Georgia. “The disease affects African Americans more aggressively. Doctors may need to monitor their African American patients more closely and take steps to prevent vision loss earlier than with other patients.”
For the study, researchers reviewed the medical records of all patients at Emory University with idiopathic intracranial hypertension during a 17-year period, from 1989-2006. Of the 450 patients, 197 were African American. There were also 246 whites, five Hispanics and two Asians in the study.
Obesity, systemic hypertension, anemia, and sleep apnea were more common in African American patients than in non-African American patients (p < /= 0.01). CSF opening pressure was higher in African American patients (40 vs 34 cm CSF, p < 0.001). Visual acuity, visual field loss, and degree of papilledema at presentation and follow-up were worse in African American patients (p < /= 0.01). Diagnostic and therapeutic measures were similar between African American patients and non- African American patients, except for optic nerve sheath fenestration (p = 0.01) and lumbar puncture (p = 0.03), both more commonly performed on African American patients.
The African American patients were 3.5 times more likely (95% CI 2.0 to 5.8, p < 0.001) to have severe vision loss in at least one eye, and 4.8 times more likely (95% CI 2.1 to 10.9, p < 0.001) to have severe vision loss in both eyes.
Bruce noted that the African Americans in the study had other risk factors, such as higher body mass index, higher frequency of anemia and higher CSF opening pressures than non-African American participants, and that these factors could partially account for the increased risk of vision loss.