A Cochrane review [Abstract] 1 included one study 2 with 120 patients with Lewy body dementia (LBD). The 10-item Neuropsychiatric Inventory Test (NPI) found no significant difference between rivastigmine and placebo groups in intention-to-treat (ITT) analysis at 20 weeks. However, the treatment effect was statistically significant in favour of rivastigmine if only observed cases were analysed (WMD -6.94, 95% CI -11.59 to -2.29). Analysis on observed cases of NPI-4 also showed significant superiority of rivastigmine to placebo at 20 weeks (WMD -3.75, 95%CI -6.62 to -0.88). There was no statistically significant difference in the MMSE score between the two groups at 20 weeks. The placebo group experienced significantly fewer adverse events than the treatment group (54/59 vs 46/61,OR 3.52, 95% CI 1.19 to 10.43). However, ITT analysis of 20-week data showed no significant difference in serious adverse events or drop-out rates.
Comment: The quality of evidence is downgraded by study quality (more than 20% loss to follow up) and by imprecise results (few patients and wide confidence intervals).
Galantamine was tested in a 24-week open-label study on 50 patients with LBD 3 showing beneficial effects in two of the three primary efficacy parameters. The scores on the NPI-12 improved by 8.24 points from baseline (p = 0.01) especially in visual hallucinations and night time behaviors (p = 0.004). The scores on the Clinician's Global Impression of Change improved by 0.5 points from baseline (p = 0.01). The third primary efficacy parameter, the Cognitive Drug Research Computerized Cognitive Assessment System, was unchanged from baseline. Adverse events were generally mild and transient.
Donepezil was evaluated in 30 patients with LBD in an open-label study 4. By 20 weeks the mean MMSE score increased by 3.9 points in the LBD group. The mean NPI score reduced by 14.6 points. These treatment effects were significant compared to baseline (p <0.001). Although adverse effects were common, they were usually mild.
Primary/Secondary Keywords