Escitalopram Plasma Concentrations in Premenopausal and Postmenopausal Women

Participants' plasma escitalopram and desmethylescitalopram levels, mental disorder severity, anthropometric measurements, bioimpedance, CYP2C19 genotype analysis, estradiol and follicle-stimulating hormone (FSH) levels, and corrected QT interval (QTc) length will be assessed. In the preliminary analysis, participants carrying the CYP2C19*1 allele will be selected from the data of 78 participants for comparative analyses. Those with the dominant allele will be selected for final analyses.

Inclusion criteria

• Aged 40 years or older and 60 years or younger
• Diagnosed with major depressive disorder and/or generalized anxiety disorder by an independent psychiatrist (not a member of the research team)
• Prescribed escitalopram treatment by an independent psychiatrist (not a member of the research team)
• Receiving escitalopram treatment for at least one month and on a stable dose for at least one week
• Willing to participate in the study and provide informed consent
• Additional inclusion criterion for the menopausal group: Amenorrhea for at least one year (consistent with menopause diagnosis)
• Additional inclusion criteria for the premenopausal group: Having regular menstrual cycles and being in the luteal phase (within 14 days after ovulation) of the menstrual cycle

Exclusion criteria

• Diagnosis of intellectual disability, dementia, psychotic disorders, schizoaffective disorder, or bipolar disorder
• Alcohol or substance use disorder
• Diagnosis of hepatic failure, renal failure, or cardiac failure
• Severe malnutrition
• Presence of an active systemic infectious or inflammatory disease
• Current use of hormone replacement therapy for menopause
• Use of oral contraceptives
• Pregnancy or breastfeeding
• Use of medications known to affect escitalopram plasma concentration
• Use of medications that affect the CYP2C19 enzyme
• Detection of alleles other than the predominant CYP2C19*1 genotype in genetic analyses