Sponsor decision

Lithium is a drug used to treat several psychiatric illnesses. This medication requires particular vigilance because it has a narrow therapeutic margin: the dose necessary to obtain an effective treatment is close to the toxic dose.

The blood dosage of the drug and the patient's knowledge of the drug are necessary to optimize and secure the drug intake.

The objective of this observational study is to confirm that the score obtained by the LKT lithium knowledge self-questionnaire translated into French is representative of the knowledge of patients treated with lithium.

Participants will be asked to complete this questionnaire twice, and the scores obtained will be compared to the blood lithium level to see if a good score is associated with an effective blood lithium concentration.

Inclusion Criteria:

• Patient hospitalized in a psychiatric ward or in an EPSM for more than 10 consecutive days
• Patient treated with IR or ER lithium LI
• Patient over 18 years of
• Patient on a fixed dosage of lithium for more than 5 days prior to blood sampling for lithiaemia testing
• Obtain patient's non-opposition

Exclusion Criteria:

• Clinically unstable patient or patient with a cognitive disorder that makes it impossible to perform interview and/or completion of the LKT self-questionnaire
• Patients under guardianship or trusteeship
• Illiterate patients
• Patient with a therapeutic target concentration different from general recommendations (e.g. elderly subject)
• Patient receiving a pharmaceutical interview or any other interview between the completion of the 1 and 2nd questionnaires, likely to modify the LKT score.

Patients hospitalized in an adult psychiatric ward or staying in an EPSM in the cities included in this study