Morningness-Eveningness questionnaire in bipolar disorder

Area of Science:

• Psychiatry
• Sleep Medicine
• Chronobiology

Background:

• The Morningness-Eveningness Questionnaire (MEQ) is a widely used tool for assessing chronotype.
• Understanding chronotype in bipolar disorder is crucial for effective treatment.

Purpose of the Study:

• To evaluate the psychometric properties of the MEQ in patients with bipolar disorder.
• To explore the relationship between chronotype, mood, sleep disturbances, and medication in this population.

Main Methods:

• 53 patients diagnosed with bipolar disorder completed the MEQ, alongside scales for mood, insomnia, and sleepiness.
• Psychometric properties of the MEQ were analyzed using Cronbach's alpha.
• Correlations between MEQ scores and clinical variables, including medication, were examined.

Main Results:

• The MEQ demonstrated high internal consistency (Cronbach's alpha = .85).
• Evening chronotype (lower MEQ scores) was significantly correlated with insomnia (r = -.34, p = .013).
• A higher prevalence of eveningness (24.5%) was observed compared to the general population.
• Lithium use was associated with higher MEQ scores (morningness), while antidepressant use was linked to lower scores (eveningness).

Conclusions:

• The MEQ is a psychometrically sound instrument for assessing chronotype in bipolar disorder.
• Chronotype, particularly eveningness, is associated with insomnia and may be influenced by psychotropic medications.
• Further research is needed to validate MEQ cut-offs and explore medication-chronotype interactions in bipolar disorder.