Department of Public Health & Preventive Medicine
Oregon Health & Science University
Title: Weight and visual field status at diagnosis in women with Idiopathic Intracranial Hypertension (IIH) Purpose: Idiopathic Intracranial Hypertension (IIH) is a disease of elevated intracranial pressure (ICP) with no identifiable cause. Signs and symptoms of elevated ICP include swelling of the optic nerve (papilledema), visual field loss, severe headache, and blindness in some cases. Previous small retrospective and prospective studies have observed a relationship between weight gain prior to or during the course of disease and vision loss. In this study, a population of women with IIH is described and the association between weight in the year prior to diagnosis and visual field deficits at diagnosis is examined. Methods: This cross-sectional study consisted of 159 females, age 13 to 65, who enrolled in the Intracranial Hypertension Registry (IHR) at Oregon Health & Sciences University between January 2003 and December 2005 and met study criteria for IIH. Study criteria expand the definition of IIH from the modified Dandy criteria to require the presence of papilledema and to include registrants with a highest lumbar puncture opening pressure of greater than or equal to 20 em cerebrospinal fluid (CSF). Existing data from mailed questionnaires completed by registrants and their physicians at the time of entry into the registry and review of registrant medical charts were used to establish signs and symptoms around the time of diagnosis. Prevalence ratios were used to assess the relationship between weight, weight gain, body mass index (BMI), and percent change in ideal body weight (IBW) during the year prior to diagnosis and abnormal visual field findings at diagnosis in either eye by formal perimetry. Results: The mean weight of the study population (n=159) one year prior to diagnosis was 92 kg (SO 27 kg). Forty-five percent of study subjects (n=62) gained 3 or more kilograms in the year prior to diagnosis, with a mean weight gain of 5 kg (SO 13 kg). Visual field findings at diagnosis were abnormal in 84% (n=122) of study subjects. Those who weighed 110 kg or greater were 0.92 times as likely (95% Cl: 0.63 to 1.33) as those who weighed less than 75 kg to have an abnormal visual field finding at the time of diagnosis. After adjustment for surgical intervention, study subjects in the highest weight category were still only 1.01 times as likely (95% Cl: 0.65 to 1.55) as those in the lowest weight category to have an abnormal visual field finding. There was also no association between abnormal visual fields at diagnosis and higher BMI, weight gain in the year prior to diagnosis, or percent change in IBW (p>0.05 for all) Conclusion: Neither weight, nor weight gain, in the year prior to diagnosis was associated with abnormal visual field status at diagnosis in this registry population of women with Idiopathic Intracranial Hypertension. Selection bias in may have resulted in a study population with more severe disease and with more obesity than other populations of women with IIH, which may have resulted in an inability to detect an association between weight and visual field deficits.
School of Medicine
Baldwin, Maureen K., "Weight and visual field status at diagnosis in women with idiopathic intracranial hypertension (IIH)" (2007). Scholar Archive. 700.