OBJECTIVES: Neurodegenerative diseases (NDs) refer to a group of diseases that affect brain cells. Alzheimer disease (AD), Parkinson disease (PD), Amyotrophique Lateral Sclerosis (ALS) and Multiple Sclerosis (MS) are the most prevalent NDs. NDs cause a substantial economic burden worldwide and indirect costs are an important component of total costs. This study aims to review relevant papers to characterize the different components of indirect costs and to identify the weight of indirect costs on total costs in different NDs. METHODS: A systematic bibliographic search was performed on an international medical literature database (MEDLINE). All studies which assessed the social economic burden and indirect costs of different NDs were selected. Indirect costs were characterized into several types (i.e. sick leave, presenteeism, early retirement, premature death, reduction in working hours, informal care time) and into several valuation (i.e. Human Capital Approach, Friction Cost Method, Willingness To Pay). RESULTS: