Mediterranean dietary pattern and depression: the PREDIMED randomized trial.
BACKGROUND
A few observational studies have found an inverse association between adherence to a Mediterranean diet and the risk of depression. Randomized trials with an intervention based on this dietary pattern could provide the most definitive answer to the findings reported by observational studies. The aim of this study was to compare in a randomized trial the effects of two Mediterranean diets versus a low-fat diet on depression risk after at least 3 years of intervention.


METHODS
This was a multicenter, randomized, primary prevention field trial of cardiovascular disease (Prevención con Dieta Mediterránea (PREDIMED Study)) based on community-dwelling men aged 55 to 80 years and women aged 60 to 80 years at high risk of cardiovascular disease (51% of them had type 2 diabetes; DM2) attending primary care centers affiliated with 11 Spanish teaching hospitals. Primary analyses were performed on an intention-to-treat basis. Cox regression models were used to assess the relationship between the nutritional intervention groups and the incidence of depression.


RESULTS
We identified 224 new cases of depression during follow-up. There was an inverse association with depression for participants assigned to a Mediterranean diet supplemented with nuts (multivariate hazard ratio (HR) 0.78; 95% confidence interval (CI) 0.55 to 1.10) compared with participants assigned to the control group, although this was not significant. However, when the analysis was restricted to participants with DM2, the magnitude of the effect of the intervention with the Mediterranean diet supplemented with nuts did reach statistical significance (multivariate HR = 0.59; 95% CI 0.36 to 0.98).


CONCLUSIONS
The result suggest that a Mediterranean diet supplemented with nuts could exert a beneficial effect on the risk of depression in patients with DM2.


BACKGROUND
This trial has been registered in the Current Controlled Trials with the number ISRCTN 35739639.
Biomedical Research Center Network on Obesity and Nutrition (CIBERobn) Physiopathology of Obesity and Nutrition, Institute of Health Carlos III, Madrid, Spain. asanchez@dcc.ulpgc.es.
Almudena
A
Sánchez-Villegas
Miguel Angel
MA
Martínez-González
Ramón
R
Estruch
Jordi
J
Salas-Salvadó
Dolores
D
Corella
Maria Isabel
MI
Covas
Fernando
F
Arós
Dora
D
Romaguera
Enrique
E
Gómez-Gracia
José
J
Lapetra
Xavier
X
Pintó
Jose Alfredo
JA
Martínez
Rosa María
RM
Lamuela-Raventós
Emilio
E
Ros
Alfredo
A
Gea
Julia
J
Wärnberg
Lluis
L
Serra-Majem
D000368:Aged; D000369:Aged, 80 and over; D002318:Cardiovascular Diseases / Q000517:prevention & control; D003863:Depression / Q000517:prevention & control*; D003924:Diabetes Mellitus, Type 2 / Q000178:diet therapy / Q000523:psychology; D038441:Diet, Mediterranean; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009754:Nuts; D000069463:Olive Oil; D010938:Plant Oils; D012307:Risk Factors; D013030:Spain / Q000453:epidemiology
D000069463:Olive Oil; D010938:Plant Oils