More than a third of children and adolescents treated for epilepsy at Uganda’s two national referral hospitals show intellectual impairment, according to a cross-sectional study published in Acta Epileptologica. Among 386 participants aged 5 to 17 years, 34.7 percent scored in the intellectually impaired range on a standardized nonverbal reasoning test, making cognitive deficit one of the most common comorbidities observed in this clinical population. The study, conducted between August 2024 and May 2025, is described by its authors as, to their knowledge, the first in Uganda to assess intellectual functioning in children and adolescents with epilepsy.
Participants were enrolled from the pediatric neurology and mental health clinics at Mulago National Referral Hospital and the Child and Adolescent Mental Health Clinic at Butabika National Referral Mental Hospital, where epilepsy accounts for a substantial share of the caseload. In Uganda, epilepsy is commonly regarded as a mental health condition and classified by the Ministry of Health under mental, neurological, and substance use disorders, so many affected children receive care primarily from mental health facilities. Using consecutive sampling, the researchers enrolled eligible children until the minimum required sample size of 385, calculated with the Kish-Leslie formula assuming a 50 percent expected prevalence and 5 percent precision, was slightly exceeded at 386 participants.
Intellectual functioning was assessed with Raven's Progressive Matrices, a nonverbal standardized test measuring mental abilities associated with abstract reasoning and problem-solving, consisting of increasingly difficult pattern-matching tasks. Children aged 5 to 11 years completed the Raven's Colored Progressive Matrices, while those aged 12 to 17 years completed the Raven's Standard Progressive Matrices. Because no established Ugandan norms exist, the researchers applied South African norms, categorizing scores into five grades based on percentiles: intellectually superior, above-average, average, below-average, and intellectually impaired. Children and adolescents with hearing, vision, or physical impairments that could interfere with their ability to respond to the study tools were excluded. Epilepsy diagnoses documented in clinic charts by psychiatrists, pediatricians, psychiatry residents, or pediatric residents, supported where indicated by investigations such as electroencephalography, were confirmed by research assistants through history-taking.
The distribution of results skewed markedly toward the lower end of the scale. Beyond the 34.7 percent classified as intellectually impaired, 32.4 percent fell into the below-average category and 26.4 percent into the average range, while only 5.7 percent scored above average and 0.8 percent reached the superior grade. There was no statistically significant difference in the distribution of performance categories between boys and girls. Participants were predominantly male, at 64.5 percent, with a mean age of 10 years, and 62.7 percent were attending school at the time of enrollment.
The study also documented a heavy burden of developmental and epilepsy-related risk factors. Nearly 40 percent of the children had experienced delayed speech, defined as a first spoken word after 18 months, and 28.1 percent had delayed walking. Early childhood onset of epilepsy, between just over one and under six years, occurred in 47.6 percent of participants, 25.3 percent had more than 10 seizures in the preceding three months, and anti-seizure medication polypharmacy was present in 34.6 percent. Over a third scored in the abnormal range on the parent-version Strengths and Difficulties Questionnaire, a behavioral screening tool previously used in Ugandan populations.
In bivariate comparisons, intellectual impairment was more prevalent among children seen at Mulago than at Butabika, among those not attending school, among those in special needs schools, and among children whose parents had no formal education. It was also more common in children with low birth weight, absence of crying at birth, neonatal admission, delayed breastfeeding initiation, speech and motor delays, earlier epilepsy onset, longer treatment duration, and polypharmacy. Behavioral problems were roughly twice as frequent in the impaired group, at 50.7 percent versus 21.2 percent.
The multivariable logistic regression, which controlled for age and sex and excluded variables with high collinearity, identified five factors positively associated with intellectual impairment and one protective factor. Children aged 12 to 17 had nearly seven times the odds of impairment compared with those aged 5 to 11 (adjusted odds ratio 6.94). Not attending school carried the strongest association (aOR 26.01), followed by attendance at a special needs school (aOR 14.50), delayed speech (aOR 3.26), and anti-seizure medication polypharmacy (aOR 3.08). Adolescent onset of epilepsy, by contrast, was strongly protective compared with neonatal or infancy onset (aOR 0.05).
The authors interpret the age and onset findings through the lens of neurodevelopment. Seizures occurring in early childhood, a sensitive period of synaptogenesis and neural network formation when synaptic proliferation peaks within the first two years after birth, may disrupt critical cognitive developmental processes, whereas many of these processes are largely completed by adolescence. The association with older age, however, remains unexplained: an interaction analysis showed that treatment duration did not modify the age effect, so the researchers suggest that unmeasured factors such as delayed diagnosis, earlier periods of poorly controlled seizures, or unmet developmental needs may be involved rather than a confirmed cumulative burden of epilepsy.
The polypharmacy association also demands cautious reading. The authors note that children requiring multiple anti-seizure medications often have treatment-resistant seizures, which are themselves linked to intellectual impairment, and that some medications can worsen cognitive function. Because the cross-sectional design cannot determine the direction of the relationship, the team calls for longitudinal studies to clarify causal pathways between polypharmacy and cognition. Similarly, the strong association with school non-attendance may reflect stigma, limited availability of special needs schools, school fees, transportation barriers, or the cognitive impairment itself, and the study cannot disentangle these directions.
Several limitations shape how the findings should be applied. The prevalence of 34.7 percent sits within the wide international range reported in the literature, which spans from 18 percent in a Nigerian study of idiopathic epilepsy to 69 percent in Tanzania, where most children were treated with phenobarbital, a medication associated with adverse cognitive effects. The authors attribute their relatively high figure partly to the tertiary-care cohort, where children with complex epilepsy and neurodevelopmental comorbidities are preferentially referred, and caution that results may not generalize to primary care or community settings. The use of South African rather than Ugandan test norms may have led to over- or under-estimation of impairment, perinatal and epilepsy-related information came from caregiver reports rather than medical records, and the exclusion of children with sensory or physical impairments may have led the study to underestimate prevalence. Even so, the authors argue the findings underscore the need for routine assessment of intellectual functioning in children with epilepsy, together with targeted interventions including academic support, speech therapy, and optimization of treatment regimens, with affected children in this study referred to a psychiatrist for further assessment and management.
Subject of Research: Prevalence and associated factors of intellectual impairment among children and adolescents with epilepsy at two national referral hospitals in Uganda
Article Title: Prevalence and factors associated with intellectual impairment in children with epilepsy in two national referral hospitals in Uganda
Article References: Arinda, A., McVoy, M., Abaatyo, J., Kaddumukasa, M., Sajatovic, M., & Katabira, E. (2026). Prevalence and factors associated with intellectual impairment in children with epilepsy in two national referral hospitals in Uganda. Acta Epileptologica, 8(1), Article 24. https://doi.org/10.1186/s42494-026-00265-3
Image Credits: AI Generated
DOI: 10.1186/s42494-026-00265-3
Keywords: epilepsy, intellectual impairment, children, Uganda, Raven's Progressive Matrices, cross-sectional study, anti-seizure medication polypharmacy, delayed speech, school attendance, neurodevelopment, tertiary care, comorbidity
News Source: Kendall Mcintyre. (October 29, 2026). One in Three Children with Epilepsy at Ugandan Hospitals Shows Intellectual Impairment. Scienmag.
