FREQUENCY OF THE BUTYRYLCHOLINESTERASE WILD-TYPE GENOTYPE IN ALZHEIMER'S PATIENTS NOT TREATED WITH RIVASTIGMINE

Abstract

In advanced stages of Alzheimer's disease (AD), butyrylcholinesterase (BuChE) progressively replaces acetylcholinesterase (AChE) in the hydrolysis of acetylcholine. This applies particularly in AD patients with the genetic variant of the BuChE wild-type, which has a higher hydrolysis rate than the frequent BuChE K-variant and is associated with a faster progression of dementia. Rivastigmine is the only commercially available AChE inhibitor, which also inhibits BuChE. Thus it may have advantages over the other AChE inhibitors, particularly in patients with BuChE wild-type. In the present study, we determined the proportion of patients with BuChE wild-type in a group of AD out-patients not treated with rivastigmine. In a multicentric study, the BuChE genotype was examined in AD patients with progressing dementia, who had no antidementive treatment or who were under treatment with either donepezil, galantamine or memantine. The study was conducted in 126 AD patients (48 men, 78 women) at ages between 57 and 94 years (mean/SD: 79.2/7.3 years); MMSE score ranged between 4 and 27 (mean/SD: 17.8/5.7). The patients were treated with either donepezil (n=58), memantine (n=29) or galantamin (N=22); 17 patients were not under antidementive medication. The BuChE wild-type was found in 95 (75.4 %) of the patients, in 89 (70.6 %) in the heterozygous and in 6 (4.8 %) in the homozygous genotype. We found the BuChE wild-type in 75 % of AD patients with progressing dementia, who were not under treatment with the BuChE inhibitor rivastigmine. In these patients, a switch of antidementive medication to rivastigmine or the initiation of rivastigmine treatment seem to be advisable.