Supplements, behaviour therapy do not prevent MDD in obese/overweight people
Neither multinutrient supplementation nor food-related behavioural activation therapy appear to protect against major depressive disorder (MDD) episodes in overweight or obese adults with subsyndromal depressive symptoms, according to a recent study.
“To our knowledge, this is the first randomized trial evaluating the effectiveness of two nutritional strategies and their combination for the prevention of depression in a high-risk group of overweight people,” said researchers. “Despite the large sample size and selection of people with elevated depressive symptoms, the onset of MDD was lower than expected, which reduced the statistical power to detect a statistically significant effect.”
The present study included four groups of overweight adults with elevated depressive symptoms: placebo with (n=256) and without (n=257) therapy, and multinutrient supplements with (n=256) and without (n=256) therapy. Only 10 percent (n=105) of participants experienced an MDD episode over the 12 months of follow-up. [JAMA 2019;321:858-868]
Stratified by groups, 25 participants (9.7 percent) in the placebo-alone arm developed MDD, while 26 (10.2 percent), 32 (12.5 percent) and 22 (8.6 percent) individuals receiving placebo with therapy, supplements alone and supplements with therapy experienced MDD onset, respectively.
Logistic regression analysis using effect-coded intervention variables revealed that neither the supplements (odds ratio [OR], 1.06; 95 percent CI, 0.87–1.29; p=0.57) nor the food-related behavioural activation therapy (OR, 0.93; 0.76–1.13; p=0.47) had a significant effect on the onset of MDD. The same was true for the interaction of these two variables (OR, 0.93; 0.76–1.14; p=0.48).
Similarly, supplements (hazard ratio [HR], 1.05; 0.86–1.27; p=0.65), therapy (HR, 0.91; 0.75–1.10; p=0.32) and their interaction (HR, 0.91; 0.75–1.11; p=0.36) were all unrelated to the time of first onset of MDD.
In terms of secondary outcomes, food-related behavioural activation therapy significantly reduced General Anxiety Disorder (GAD) scale scores at 12 months (adjusted mean difference [MD], –0.48; –0.84 to –0.12; p=0.01), while supplements had an opposite effect (adjusted MD, 0.50; 0.16–0.84; p=0.004). The interaction of both variables was null.
“This study showed that multinutrient supplements containing omega-3 [polyunsaturated fatty acids], vitamin D, folic acid and selenium neither reduced depressive symptoms, anxiety symptoms, nor improved health utility measures. In fact, they appeared to result in slightly poorer depressive and anxiety symptoms scores compared with placebo,” said researchers.
In contrast, behavioural therapy appeared to provide significant benefits regarding depressive and anxiety symptoms and MDD onset, they continued. “This suggests that with sufficient dose and a higher-risk sample, food-related behavioural activation therapy might prevent depression, although this requires further study.”
“It would be relevant to study which characteristics make participants more likely to adhere to the intervention, to identify persons who may benefit from it,” they added.