Organized Registration for the Assessment of Dementia by the Nationwide General Consortium Toward Effective Treatment (ORANGE) Registry: Current Status and Perspectives of Mild Cognitive Impairment

Background: With increasingly aging societies, a comprehensive strategy for dementia research is important. The Organized Registration for the Assessment of dementia by the Nationwide General consortium toward Effective treatment (ORANGE) Registry is the first longitudinal multicenter prospective trial-ready cohort in Japan. Objective: To establish a large cohort for use in clinical trials and research in Japan. Methods: This registry, based on communities, hospitals, and nursing homes, covers three dementia stages (preclinical, mild cognitive impairment [MCI], and advanced dementia), and includes more than 30 hospitals. We analyzed enrollment and 1-year follow-up data for disease progression. Results: There were 1450 registered patients (649 men, 801 women; mean age, 77.92 +/- 6.70 years; mean Mini-Mental State Examination [MMSE] score, 25.19 +/- 2.76). The conversion rates from MCI to dementia and MCI to normal were 14.3% and 1.1%, respectively. High Clinical Dementia Rating score (odds ratio [OR] = 11.085, 95% confidence interval [CI]:1.619-75.913, p = 0.014), low MMSE score (OR = 0.835, 95% CI: 0.761-0.917, p < 0.001), high Geriatric Depression Scale score (OR = 1.093, 95% CI: 1.005-1.189, p = 0.038), and low body mass index (OR = 0.895, 95% CI: 0.829-0.967, p = 0.005) at enrollment were significant factors for conversion. Conclusion: The ORANGE MCI Registry is an established registry that facilitates creation of trial-ready cohorts to accelerate promotion of clinical trials with low reversion rates as it originates from a hospital. One-year follow-up analysis suggested assessing various factors for conversion risk. Further analyses will be possible in future with registry expansion. We will continue to refine this registry, including how it can be used more efficiently.