Research article
Frequency of nut consumption and mortality risk in the PREDIMED nutrition intervention trial
1 Human Nutrition Unit, Hospital Universitari de Sant Joan de Reus, Faculty of Medicine and Health Sciences, IISPV (Institut d’Investigació Sanitària Pere Virgili), Universitat Rovira i Virgili, Reus, Spain
2 CIBERobn (Centro de Investigación Biomédica en Red Fisiopatología de la Obesidad y Nutrición), Institute of Health Carlos III, Madrid, Spain
3 Department of Preventive Medicine and Public Health, University of Navarra, Pamplona, Spain
4 Lipid Clinic, Department of Endocrinology and Nutrition, Institut d’Investigacions Biomediques August Pi Sunyer (IDIBAPS), Hospital Clinic, University of Barcelona, Barcelona, Spain
5 Department of Preventive Medicine, University of Valencia, València, Spain
6 Department of Internal Medicine, Institut d’Investigacions Biomèdiques August Pi Sunyer (IDIBAPS), Hospital Clínic, University of Barcelona, Barcelona, Spain
7 Cardiovascular Risk and Nutrition Research Group, Institut Hospital del Mar d’Investigacions Mèdiques (IMIM), Barcelona Biomedical Research Park, Barcelona, Spain
8 Department of Cardiology, University Hospital Txagorritxu, Vitoria, Spain
9 Department of Preventive Medicine, University of Malaga, Malaga, Spain
10 Institute of Health Sciences, University of Balearic Islands and Hospital Son Espases, Palma de Mallorca, Spain
11 Department of Family Medicine, Primary Care Division of Sevilla, San Pablo Health Center, Sevilla, Spain
12 Primary Health Care Division and Research, Instituto de Investigaciones Biomédicas August Pi i Sunyer-Jordi Gol, Barcelona, Spain
13 INSA, University of Barcelona, Barcelona, Spain
14 Department of Clinical Sciences, University of Las Palmas de Gran Canaria, Las Palmas, Spain
15 Lipids and Vascular Risk Unit, Internal Medicine, Hospital Universitario de Bellvitge, Hospitalet de Llobregat, Barcelona, Spain
16 Instituto de la Grasa, Consejo Superior de Investigaciones Científicas, Sevilla, Spain
BMC Medicine 2013, 11:164 doi:10.1186/1741-7015-11-164
Published: 16 July 2013Abstract
Background
Prospective studies in non-Mediterranean populations have consistently related increasing nut consumption to lower coronary heart disease mortality. A small protective effect on all-cause and cancer mortality has also been suggested. To examine the association between frequency of nut consumption and mortality in individuals at high cardiovascular risk from Spain, a Mediterranean country with a relatively high average nut intake per person.
Methods
We evaluated 7,216 men and women aged 55 to 80 years randomized to 1 of 3 interventions (Mediterranean diets supplemented with nuts or olive oil and control diet) in the PREDIMED (‘PREvención con DIeta MEDiterránea’) study. Nut consumption was assessed at baseline and mortality was ascertained by medical records and linkage to the National Death Index. Multivariable-adjusted Cox regression and multivariable analyses with generalized estimating equation models were used to assess the association between yearly repeated measurements of nut consumption and mortality.
Results
During a median follow-up of 4.8 years, 323 total deaths, 81 cardiovascular deaths and 130 cancer deaths occurred. Nut consumption was associated with a significantly reduced risk of all-cause mortality (P for trend <0.05, all). Compared to non-consumers, subjects consuming nuts >3 servings/week (32% of the cohort) had a 39% lower mortality risk (hazard ratio (HR) 0.61; 95% CI 0.45 to 0.83). A similar protective effect against cardiovascular and cancer mortality was observed. Participants allocated to the Mediterranean diet with nuts group who consumed nuts >3 servings/week at baseline had the lowest total mortality risk (HR 0.37; 95% CI 0.22 to 0.66).
Conclusions
Increased frequency of nut consumption was associated with a significantly reduced risk of mortality in a Mediterranean population at high cardiovascular risk.
Please see related commentary: http://www.biomedcentral.com/1741-7015/11/165 webcite.
Trial registration
Clinicaltrials.gov. International Standard Randomized Controlled Trial Number (ISRCTN): 35739639. Registration date: 5 October 2005.
