ABSTRACT
BACKGROUND: The Neuropsychiatric Inventory (NPI) is widely used to assess psychopathology in dementia. The scoring involves ratings of frequency and severity, as well as the calculation of a composite score. It was suggested recently that, due to lower variance, the frequency score might be more sensitive to detect treatment-related change and to discriminate active treatment from placebo than the composite score, particularly in milder forms of the disease. METHODS: Based on data from three randomized controlled trials in patients with mild to moderate dementia, standardized changes were calculated for both frequency and composite scores for two strata of disease severity. The two strata were formed by dichotomizing the sample along the median score of the short cognitive performance test (SKT) battery. RESULTS: Across all studies and for both severity strata, standardized changes in frequency scores were not consistently larger than those in composite scores and both scores discriminated active treatment from placebo at similar probabilities for type-1 error. CONCLUSION: Our findings do not support the notion that there is a difference between frequency score and composite score with respect to their sensitivity to treatment-related change.
Subject(s)
Dementia/drug therapy , Dementia/psychology , Neuropsychological Tests , Psychiatric Status Rating Scales , Aged , Dementia/diagnosis , Dementia/pathology , Female , Ginkgo biloba , Humans , Male , Middle Aged , Phytotherapy/methods , Plant Extracts/therapeutic use , Psychopathology , Randomized Controlled Trials as Topic , Regression Analysis , Reproducibility of Results , Sensitivity and Specificity , Severity of Illness Index , Treatment OutcomeABSTRACT
A multi-centre, double-blind, randomised, placebo-controlled, 24-week trial with 410 outpatients was conducted to demonstrate efficacy and safety of a 240 mg once-daily formulation of Ginkgo biloba extract EGb 761(®) in patients with mild to moderate dementia (Alzheimer's disease or vascular dementia) associated with neuropsychiatric symptoms. Patients scored 9 to 23 on the SKT cognitive battery, at least 6 on the Neuropsychiatric Inventory (NPI), with at least one of four key items rated at least 4. Primary outcomes were the changes from baseline to week 24 in the SKT and NPI total scores. The ADCS Clinical Global Impression of Change (ADCS-CGIC), Verbal Fluency Test, Activities of Daily Living International Scale (ADL-IS), DEMQOL-Proxy quality-of-life scale and 11-point box scales for tinnitus and dizziness were secondary outcome measures. Patients treated with EGb 761(®) (n = 200) improved by 2.2 ± 3.5 points (mean ± sd) on the SKT total score, whereas those receiving placebo (n = 202) changed only slightly by 0.3 ± 3.7 points. The NPI composite score improved by 4.6 ± 7.1 in the EGb 761(®)-treated group and by 2.1 ± 6.5 in the placebo group. Both drug-placebo comparisons were significant at p < 0.001. Patients treated with EGb 761(®) also showed a more favourable course in most of the secondary efficacy variables. In conclusion, treatment with EGb 761(®) at a once-daily dose of 240 mg was safe and resulted in a significant and clinically relevant improvement in cognition, psychopathology, functional measures and quality of life of patients and caregivers.
