Analyses of natural courses of Japanese patients with Alzheimer's disease using placebo data from placebo-controlled, randomized clinical trials: Japanese Study on the Estimation of Clinical course of Alzheimer's disease

Mitsunori Watanabe; Yu Nakamura; Yasumasa Yoshiyama; Tatsuo Kagimura; Hiroyuki Kawaguchi; Hiroshi Matsuzawa; Yosuke Tachibana; Kazuma Nishimura; Naoki Kubota; Masato Kobayashi; Takayuki Saito; Kaoru Tamura; Takayuki Sato; Masayoshi Takahashi; Japanese Society of Scaling Keys of Evaluation Techniques for CNS Disorders Heterogeneity (SKETCH) study group; Akira Homma

doi:10.1016/j.trci.2019.07.004

Analyses of natural courses of Japanese patients with Alzheimer's disease using placebo data from placebo-controlled, randomized clinical trials: Japanese Study on the Estimation of Clinical course of Alzheimer's disease

Alzheimers Dement (N Y). 2019 Aug 29:5:398-408. doi: 10.1016/j.trci.2019.07.004. eCollection 2019.

Authors

Mitsunori Watanabe¹, Yu Nakamura^{1

2}, Yasumasa Yoshiyama^{1

3}, Tatsuo Kagimura^{1

4}, Hiroyuki Kawaguchi¹, Hiroshi Matsuzawa¹, Yosuke Tachibana¹, Kazuma Nishimura¹, Naoki Kubota¹, Masato Kobayashi¹, Takayuki Saito¹, Kaoru Tamura¹, Takayuki Sato¹, Masayoshi Takahashi¹; Japanese Society of Scaling Keys of Evaluation Techniques for CNS Disorders Heterogeneity (SKETCH) study group; Akira Homma^{1

5}

Affiliations

¹ Japanese Society of Scaling Keys of Evaluation Techniques for CNS Disorders Heterogeneity (SKETCH), Tokyo, Japan.
² Department of Neuropsychiatry, Kagawa University School of Medicine, Kagawa, Japan.
³ Inage Neurology and Memory Clinic, Chiba, Japan.
⁴ Translational Research Center for Medical Innovation (TRI), Foundation for Biomedical Research and Innovation at Kobe, Kobe, Japan.
⁵ Otafuku Memory Clinic, Ibaraki, Japan.

Abstract

Introduction: Symptomatic anti-Alzheimer's disease (AD) drugs have been commonly used for the treatment of AD. Knowing the natural courses of patients with AD on placebo is highly relevant for clinicians to understand their efficacy and for investigators to design clinical studies.

Methods: The data on rating scales for dementia such as Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog) and Severe Impairment Battery were extracted from eight previous Japanese Phase II and III studies. Natural courses of Japanese AD patients in placebo groups were evaluated and statistically analyzed in a pooled and retrospective fashion.

Results: Decreases in ADAS-cog and Severe Impairment Battery was larger at week 22 or 24 than at week 12. Scores of ADAS-cog appeared to deteriorate faster in moderate AD than in mild AD.

Discussion: The present data will provide clinicians following up patients with AD with helpful information on how to manage AD patients and investigators with instruction for clinical study design.

Keywords: ADAS-cog; Acetylcholine esterase inhibitor; Alzheimer's disease; Memantine; Mini-Mental State Examination; Natural course; Severe Impairment Battery.