Inclusion Criteria:  Patients over 70 years of age With moderate or severe neurocognitive disorders of any etiology (Mini Mental State Examination (MMSE) less than or equal to 20, or not feasible) Resident in EHPAD (establishment for dependent elderly people) or USLD (long-term care unit ) in permanent accommodation for more than 1 month at inclusion  Exclusion Criteria:  Patient with presumed life expectancy of less than 3 months Mini Mental State Examination (MMSE) not feasible for any reason other than cognitive impairment (e.g. stroke aphasia), without dementia Known carrier of multi-drug resistant bacteria Carrier of Pace-maker (precautionary advice from manufacturer) Refusal to participate to the study (trusted person, guardian or curator or patient depending on the patient's mental state) Patient under court protection Prior inclusion in an interventional study that may alter the interpretation of the results of the analysis Patient not affiliated to a social security system or beneficiary of such a system