The prevalence of dementia and cognitive impairment in patients with neurocysticercosis: a systematic review and meta-analysis

Neurocysticercosis (NCC) is a leading parasitic infection of the central nervous system and an important cause of neurological morbidity in endemic regions. Although seizures are well-characterized manifestations, the burden of cognitive impairment and dementia in NCC remains poorly quantified. This systematic review and meta-analysis aimed to estimate the prevalence of cognitive impairment and dementia among patients with NCC and to explore sources of between-study variability. Following PRISMA guidelines, we searched PubMed, Scopus, Web of Science, and Google Scholar (June–July 2025) and registered the protocol in PROSPERO (CRD420251106614). Observational studies reporting dementia or cognitive impairment in imaging-confirmed NCC were eligible. Data extraction and quality assessment were independently performed, and risk of bias was evaluated using the Hoy tool. Pooled prevalence estimates were generated using random-effects models with REML and Hartung–Knapp adjustments. Exact binomial (Clopper–Pearson) confidence intervals and logit-transformations were applied. Prespecified subgroup, meta-regression, and sensitivity analyses assessed heterogeneity. Nine studies met inclusion criteria ( N = 798 for cognitive impairment; N = 296 for dementia). The pooled prevalence of cognitive impairment was 50% (95% CI: 0.23–0.76; I²=97.87%) and dementia 10% (95% CI: 0.05–0.15; I²=49.11%). Subgroup analyses showed significant regional variation, with highest cognitive impairment prevalence in South America (68%). Cognitive assessment method did not account for heterogeneity. Sensitivity analyses confirmed the robustness of pooled estimates, and no significant small-study effects were detected. Cognitive impairment affects approximately half of patients with NCC, while one in ten develop dementia. Geographic context and methodological factors largely drive between-study variability. These findings underscore NCC as an important contributor to neurocognitive morbidity in endemic regions and highlight the need for standardized cognitive assessment, harmonized diagnostic criteria, and longitudinal studies to clarify disease mechanisms and progression.