Efficacy of EMONO as an add-on Therapy to Conventional Antidepressants for the Treatment of Depressive Symptoms in Nursing-home Residents With Neurocognitive Disorders: a Randomized Controlled Trial-

Efficacy of EMONO as an add-on Therapy to Conventional Antidepressants for the Treatment of Depressive Symptoms in Nursing-home Residents With Neurocognitive Disorders: a Randomized Controlled Trial

Depression in neurocognitive disorders (Alzheimers' disease and related disoders) is a highly prevalent condition, especially in nursing homes. While it is associated with significant distress, the current conventional antidepressants have shown only modest efficacy and exposed to potentially severe side effects.

Recent evidence suggests that nitrous oxide (N2O) in its most commonly used packaging of EMONO (Equimolar Mixture of Oxygen and Nitrous Oxide) has rapid antidepressant properties and a good safety profile. However, no study has investigating the antidepressant effect of EMONO in a population of depressed older adults with moderate to severe neurocognitive disorders in nursing homes.

The principal goal of the PROTO-EHPAD study is to compare the changes in depressive symptoms in such individuals in a randomized controlled trial with a follow up period of 8 weeks, with a dosage escalation procedure.

Participants will be exposed to 3 sessions of EMONO (or Medical Air), with intervals of 1 week between sessions : a first session of 20 minutes, a second of 40 minutes one week later and a final session of 60 minutes one week later. Efficacy will be assessed 1 week after each session and 4 weeks after the last session.

Inclusion Criteria:

• Men and women aged 60 and over living in nursing home
• Diagnosis of major neurocognitive disorder according to DSM-V for at least 6 month
• MMSE <= 20/30
• NPI depression >= 4/12
• Patient, family and legal representive consent where applicable Person affiliated to a social security schem

Exclusion Criteria:

• NPI agitation > 6/12
• Unstable somatic pathology (in particular unstable neurological or cardiological pathologies at risk of interfering with the diffusion of MEOPA) and any unexplained recent neurological abnormality.
• Contraindications to the use of MEOPA
• Patients who have already been treated with MEOPA in the 6 months prior to inclusion, for example for painful treatment
• Sub-physiological plasma vitamin B12 or B9 concentration (below the lower limit of the laboratory value).
• A person participating in a clinical drug study or in a period of exclusion from any clinical study due to previous participation
• Personne participant à une étude clinique médicamenteuse ou en période d'exclusion de toute étude clinique du fait d'une précédente participation