Dietary Quality in Bipolar Disorder Compared to Unipolar Depression (Current and Remitted) and Healthy Controls: The...

Patients with bipolar disorder (BD) have an increased risk to develop cardiovascular disease. Western diets have been hypothesized to increase the risk of cardiovascular disease in BD, but dietary habits in BD have not been extensively studied. We therefore assessed in a large cohort dietary quality in BD patients, in patients with current and remitted unipolar depression (UD), and healthy controls (HC).

In total 1358 participants were included from the Netherlands Study of Depression and Anxiety (NESDA) and categorized into four groups: BD (n = 100, 48.0% male, mean age 50.9), current UD (n = 199, 28.0% male, mean age 52.4), remitted UD (n = 722, 29.8% male, mean age 52.4), and HC (n = 337, 40.7% male, mean age 51.2). Diet was assessed through the 238-item Food Frequency Questionnaire (FFQ), which yielded the 'Mediterranean Diet Score' (MDS). Dietary scores were compared using multivariate regression analyzes adjusting for sociodemographics, physical activity, and smoking.

BD patients scored significantly lower on the MDS than those with remitted UD (p = 0.01) and healthy controls (p = 0.02) but did not differ from those with current UD. Effect sizes were 0.24 for BD vs. remitted UD and 0.25 for BD vs. HC. Furthermore, BD patients had on average a higher waist circumference (p = 0.03) and BMI (p = 0.02) than healthy controls.

The average dietary quality of BD patients was of lesser quality compared to that in patients with remitted UD and HC. This may have contributed to the increased waist circumference and higher BMI we found among BD patients, with its adverse health consequences.