Abstract

Objective: To evaluate cognitive outcome in adult survivors of bacterial meningitis

Methods: Data from three prospective multi-center studies were pooled and re-analyzed, involving 155 adults surviving bacterial meningitis (79 after pneumococcal and 76 after meningococcal meningitis) and 72 healthy controls.

Results: Cognitive impairment was found in 32% of the patients and this proportion was similar for survivors of pneumococcal and meningococcal meningitis. Patients after pneumococcal meningitis performed worse on memory tasks (P < 0.001) and tended to be cognitively slower than patients after meningococcal meningitis (P = 0.08). We found a diffuse pattern of cognitive impairment, in which cognitive speed played the most important role. Cognitive performance was not related to time since meningitis; however, there was a positive association between time since meningitis and self-reported physical impairment (P <0.01). The frequency of cognitive impairment and the numbers of abnormal test results for patients with and without adjunctive dexamethasone were similar.

Conclusions: Adult survivors of bacterial meningitis are at risk for cognitive impairment, which consist mainly of cognitive slowness. The loss of cognitive speed is stable over time after bacterial meningitis; however, there is a significant improvement of subjective physical impairment in the years after bacterial meningitis. The use of dexamethasone was not associated with cognitive impairment.