Long-term Outcome of Haemophilus influenzae Meningitis in Navajo Indian Children

OBJECTIVES: To determine the long-term neurologic, cognitive, and educational outcomes of Navajo children who survived Haemophilus influenzae type b meningitis. DESIGN: Retrospective cohort study, with 3.6- to 15.0-year follow-up. SETTING: Navajo Indian reservation. PARTICIPANTS: Population-based cohort of 76 Navajo children with Haemophilus meningitis at less than 5 years of age between 1975 and 1986, with 41 (54%) consenting to undergo follow-up in 1990. Each case was matched to one nearest-age sibling and one unrelated age-matched control. MAIN OUTCOME MEASURES: Standard intelligence test scores, neurologic abnormalities, and school performance. RESULTS: The mean IQ for cases was lower than that for siblings (79 vs 87, P = .006) or age-matched controls (79 vs 95, P < .001). Twenty-nine percent of cases had severe neurologic sequelae, including mental retardation (24%), severe hearing loss (5%), cerebral palsy (7%), and seizure disorder (12%). Eight percent of siblings (relative risk for cases vs siblings, 8.0; P = .05) and 2% of age-matched controls (relative risk vs cases, 10.0; P = .01) had mental retardation. No siblings or age-matched controls had any other severe neurologic sequela. Twenty-nine percent of cases, 23% of siblings (relative risk, 2.5; P = .45), and 0% of age-matched controls (P = .001) required special education services, while 42% of cases, 23% of siblings (relative risk, 3.3; P = .10), and 11% of age-matched controls (relative risk, 4.0; P = .005) had been retained in a grade in school. CONCLUSIONS: Navajo survivors of Haemophilus meningitis suffer more long-term neurologic, cognitive, and school-related disability than siblings or age-matched controls. They may also suffer higher morbidity than Haemophilus meningitis survivors in the general population.