P.1.j.009 Breaking evidence from a human object pattern separation test of disrupted hippocampal dentate gyrus activity in schizophrenics

Abstract

But extensive assessment by experienced neuropsychologists is hardly feasible in everyday practice for large numbers of patients, especially in outpatient clinics and private practices. This implies a risk of delaying or missing relevant cognitive impairments before and during treatment. Methods: We introduce a computerized screening instrument which allows for standardized assessment of cognitive functions at risk of medication. It was evaluated by standard neuropsychological tests and covers the cognitive domains of attention, cognitive speed, verbal and visual working memory as well as verbal and spatial memory. The test consists of six subtests which take 30 minutes to complete; afterwards the patient’s results are displayed immediately in comparison to age-related normative data. For psychometric evaluation, data were gathered from patients with epilepsy (n = 240), as an example for a chronic neurological disease treated with psychoactive antiepileptic medication (n = 42 untreated, n = 79 monotherapy, n = 119 polytherapy). Results: Comparability to standard neuropsychological tests (0.64 r 0.82) as well as retest reliability (0.40 r 0.79) were shown to be good for the subtests. It could be shown that the screening system is able to detect adverse cognitive effects of antiepileptic medication. Untreated patients showed a generally better performance than those on monotherapy or polytherapy. Comparisons between untreated patients and patients on monotherapy did not differ significantly. Groups of mono-/polytherapy differed significantly (p< 0.05) with lower scores for patients on polytherapy than on monotherapy in most subtests. These differences become even more obvious, as patients on monotherapy did significantly better compared to patients on three or more drugs in most subtests (p< 0.05). Also, the screening demonstrates significant cognitive changes in intra-individual assessment related to titration or withdrawal of antiepileptic drugs (e.g. topiramate). Conclusions: Medicationand dosage-related effects in the individual’s cognitive profile could be demonstrated by the screening instrument, indicating that a regular assessment of these functions, e.g. during change of therapy, is essential to keep track of adverse side effects and to optimize therapeutic interventions in neurological and psychiatric diseases. Also, the necessity of psychoactive drug polytherapy should be well-considered, as it is often associated with severe cognitive impairment. Early detection of deficits facilitates an in time intervention. The introduced screening instrument with its two different versions provides a standardized, time-efficient and individual follow-up assessment of cognitive functions and is valuable for clinical and scientific use.