Professor Vahl reminds us of the importance of normal pressure hydrocephalus as a differential diagnosis for dementia with motor symptoms. This disorder is indeed common and is often not recognized, although it is very well treatable by means of repeated lumbar puncture or surgical shunt implantation (1). This also underlines the importance of cerebral imaging (magnetic resonance imaging [MRI] is the technique of choice) in dementia and/or gait disturbances, which is often not performed. Without MRI the diagnosis of normal pressure hydrocephalus will be missed.
Dr Landau questions the use of cholinesterase inhibitors in Parkinson’s disease with dementia. We mentioned in our article the controlled study using rivastigmine (2). A clinically notable improvement was seen in 19.8% of patients in the group receiving the drug but also in 14.5% in patients receiving placebo. Deterioration was noted in 13% in the “verum” group and 23.1% in the placebo group. These effects are low with respect to the total study group, but currently no clinically relevant alternative treatments are available. The study reported by Emre and colleagues is the only larger one with rivastigmine. A second study of a similar order of magnitude would be desirable. No controlled studies are currently available for comparable substances.
Personally in our clinical practice we often see clinical stabilization of patients with Lewy body dementia after starting treatment with rivastigmine, in the form of cognitive improvement and reduced hallucinations
Footnotes
Conflict of interest statement
Professor Trenkwalder has received honoraria for presentations or advisory board meetings from Cephalon, Boehringer Ingelheim, GlaxoSmithKline, Novartis, Solvay, TEVA, and Schwarz/UCB Pharma.
Dr Mollenhauer receives financial funding from the Michael J Fox Foundation for Parkinson’s Research, the American Parkinson Disease Association, and through a Dr Werner Jackstädt scholarship (Stifterverband für die Deutsche Wissenschaft—a German industry initiative promoting science and learning) and is in receipt of research funds from TEVA. She has received travel expenses from Boehringer- Ingelheim and Novartis and honoraria for speaking from GlaxoSmithKline and Bayer Schering Pharma AG.
References
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