LAUSR

Dear Editor, I have read the article entitled as BThe Italian dementia with Lewy bodies study group (DLB-SINdem): toward a standardization of clinical procedures and multicenter cohort studies design^ by Bonanni et al. with interest [1]. The authors presented a standardized procedure for the diagnosis of dementia with Lewy bodies (DLB) in Italy. During the process, DLB prevalence in comparison with Alzheimer’s disease and frontotemporal dementia were 24.5 and 57.5% in primary centers. These values became 21.1 and 51.4% in tertiary centers. I want to add some recent information on the prognosis of DLB. First, Graff-Radford et al. identified factors of disease duration in patients with DLB [2]. DLB was classified into transitional and diffuse type and disease duration was defined from cognitive symptom onset to death. Men, later age at onset, and diffuse type were significant variables of short disease duration in patients with DLB. In contrast, Braak neurofibrillary tangle stage and the presence of neuritic plaques were not associated with disease duration. According to the standardized procedure for the diagnosis of DLB, these factors should be evaluated as predictors of prognosis for DLB. Second, Yoon et al. presented the screening ability of olfactory and neuropsychological tests on the differentiation of DLB from Alzheimer’s disease (AD) at the mild cognitive impairment (MCI) stage to avoid DLB progression [3], which was cited by Bonanni et al. [1]. Olfactory function was measured with the Cross-Cultural Smell Identification (CCSI) test, and Rey Complex Figure Test (RCFT) was applied for the assessment of recall and recognition. Among 122 MCI patients, 32 subjects developed probable AD and 18 had probable DLB. By multiple logistic regression analysis, odds ratios of CCSI and RCFT for DLB versus AD significantly decreased. Early screening of DLB during MCI period would make longer disease duration from cognitive symptom onset to death, and olfactory and neuropsychological tests should also be included for the risk assessment of DLB. Third, Garcia Basalo et al. presented a validation study on the early detection tool for DLB, named ALBA Screening Instrument (ASI) [4]. ASI is a clinical and neuropsychological scale, which is not based on the biological test. The subjects were limited to patients who have ability to answer the questions and to obey physical examination. Among 427 subjects withMMSE score >20, 75 patients with DLB and 121 patients with other dementias were classified. Receiver operating characteristic curve analysis showed a sensitivity of 90.7% and a specificity of 93.6% for differentiating DLB from other dementia, MCI, and healthy controls. These data present that not only biological markers but also neuropsychological scales are useful to detect DLB. Bonanni et al. presented database on DLB, which will be used for prospective studies to clarify the prognosis of DLB [1]. As the information on the prognosis of DLB was limited, database setting in other countries is also recommended to confirm the ethnic difference of epidemiological information on DLB. * Tomoyuki Kawada [email protected]