Epidemiology of idiopathic intracranial hypertension: a prospective and case-control study.

An epidemiologic survey of idiopathic intracranial hypertension (IIH) in Benghazi, Libya, over a period from September 1982 through August 1989 ascertained 81 patients. The group was comprised of 76 females and 5 males. Ages ranged from 8 to 55 years; the mean +/- S.D. was 28.6 +/- 7.9 for women and 21.0 +/- 14.5 for men. The average crude annual incidence rates for IIH per 100,000 persons were 2.2 for the total and 4.3 for females for all ages (3.2 for the total and 5.9 for the females when adjusted to the 1980 United States population). In females aged 15-44 years, IIH occurred at a rate of 12.0 per 100,000 per year; for those defined as obese, the rate rose to 21.4. Moderate to severe visual loss occurred as a sequelae in 20% of our patients. The extent of visual loss did not correlate with age at diagnosis, duration of symptoms, degree of obesity, use of oral contraceptive pills, cerebrospinal fluid (CSF) opening pressure, steroid treatment, or recurrence. We found no correlation between CSF protein and opening pressure. We conducted a case-control study on 40 consecutive female incident IIH patients and 80 age-matched female control subjects. Obesity and recent weight gain occurred more frequently in patients. More patients were married and more had irregular menses. The incidence rate for IIH described in our study is three to four times higher than that reported from the United States.

Descriptive epidemiology of some rare neurological diseases in Benghazi, Libya.

During a 4-year study period, January 1983 to December 1986, 24 patients (18 index cases) with spinal muscular atrophy (hereditary motor neuropathy, HMN), 9 with myasthenia gravis (MG), 6 with progressive supranuclear palsy (PSP), and 5 with subacute sclerosing panencephalitis (SSPE) were diagnosed in Benghazi. The HMN group comprised 6 acute infantile, 12 chronic childhood, and 3 each with adult-onset proximal, and distal forms of the disease. The crude average annual incidence of acute infantile HMN was 0.3/100,000 total population and 1/12,500 births in Benghazi. The crude prevalence rates of chronic childhood, adult-onset proximal, and distal types of HMN were 2.3, 0.6 and 0.6/100,000, respectively. The larger family size and the high rate of consanguineous marriages contribute to the high frequency of HMN in the study area. Distal HMN constituted 12.5% of the total cases. The adjusted average incidence of MG was 4.4/million/year, 2.1 for males and 6.8 for females. The female:male incidence ratio was 3.2:1. The crude average annual incidence rates/million inhabitants for PSP asnd SSPE were 3 and 2.4, respectively. The frequency of occurrence of SSPE among the subtropical Arab community under investigation is comparable with other surveys from the Middle East and Mediterranean region.