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Adherence to Mediterranean Diet and NAFLD in Patients with Metabolic Syndrome: The FLIPAN Study.
Montemayor, S, Mascaró, CM, Ugarriza, L, Casares, M, Llompart, I, Abete, I, Zulet, MÁ, Martínez, JA, Tur, JA, Bouzas, C
Nutrients. 2022;14(15)
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Non-alcoholic fatty liver disease (NAFLD) is characterised by fat deposition that is not linked to excessive alcohol intake. This condition is often linked to other health issues such as obesity, metabolic syndrome, type 2 diabetes and cardiovascular disease, and they share common diagnostic biomarkers. An unhealthy diet and lifestyle are also linked to the progression of NAFLD. Mediterranean diet is a predominantly plant-based diet that may have an association with lower risk and reduced severity of NAFLD. This multicentre, prospective, randomised controlled trial included one hundred and thirty-six NAFLD patients to analyse the effect of Mediterranean diet adherence on NAFLD in patients with metabolic syndrome. The NAFLD patients followed a personalised Mediterranean diet and physical activity interventions for six months. Individuals with greater adherence to the Mediterranean diet and physical activity interventions showed improvements in body mass index, body weight, waist circumference, blood pressure and intrahepatic fat content after six months of intervention. Healthcare professionals can use the results of this study to understand the benefits of adherence to the Mediterranean diet and physical activity interventions in reducing NAFLD severity and metabolic irregularities. However, due to the small sample size of this study, further robust studies are required to evaluate the benefits of different dietary strategies, the therapeutic value of different food items and the intervention duration required to achieve improvements in NAFLD and metabolic syndrome.
Abstract
Unhealthy diet is an important factor in the progression of non-alcoholic fatty liver disease (NAFLD). Previous studies showed the benefits of a Mediterranean diet (MedDiet) on Metabolic syndrome (MetS), type 2 diabetes mellitus (T2DM), and cardiovascular diseases, which usually have a pathophysiological relationship with NAFLD. To assess the effect of adherence to a MedDiet on NAFLD in MetS patients after lifestyle intervention, this multicentre (Mallorca and Navarra, Spain) prospective randomized trial, with personalized nutritional intervention based on a customized MedDiet, coupled with physical activity promotion was performed to prevent, and reverse NAFLD among patients with MetS. The current analysis included 138 patients aged 40 to 60 years old, Body Mass Index (BMI) 27-40 kg/m2, diagnosed with NAFLD using MRI, and MetS according to the International Diabetes Federation (IDF). A validated food frequency questionnaire was used to assess dietary intake. Adherence to Mediterranean diet by means of a 17-item validated questionnaire, anthropometrics, physical activity, blood pressure, blood biochemical parameters, and intrahepatic fat contents (IFC) were measured. The independent variable used was changes in MedDiet adherence, categorized in tertiles after 6 months follow-up. Subjects with high adherence to the MedDiet showed higher decreases in BMI, body weight, WC, SBP, DBP, and IFC. An association between improvement in adherence to the MedDiet and amelioration of IFC after 6-month follow-up was observed. High adherence to the MedDiet is associated with better status of MetS features, and better values of IFC.
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The Effect of Moderate Weight Loss on a Non-Invasive Biomarker of Liver Fibrosis: A Randomised Controlled Trial.
Koutoukidis, DA, Jebb, SA, Aveyard, P, Astbury, NM
Obesity facts. 2020;13(2):144-151
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Non-alcoholic fatty liver disease covers a range of conditions from excess fat in the liver through inflammation and fibrosis, to advanced fibrosis, and cirrhosis. The Enhanced Liver Fibrosis (ELF) score is emerging as a promising blood biomarker for fibrosis. The aim of this study was to examine whether a community weight loss programme reduces ELF score over 12 months compared with a weight-loss intervention which is less effective. This study is a secondary analysis of a published randomised controlled trial. Participants (n=73) were equally randomised to a community weight loss programme (WeightWatchers) or usual care. Results indicate that there was no evidence of an effect of a community weight loss programme on changes in the ELF score and no association between weight loss and the ELF score in people who had, on average, an ELF score compatible with moderate fibrosis. Authors conclude that using the ELF test to assess weight loss treatment efficacy in improving liver fibrosis may be of limited value, thus biopsy remains the gold-standard assessment for liver fibrosis.
Abstract
BACKGROUND Referral to weight loss programmes is the only effective treatment for non-alcoholic fatty liver disease (NAFLD). Clinicians should advise weight loss and screen for liver fibrosis using the Enhanced Liver Fibrosis (ELF) score. AIM: To examine if the ELF score changes with weight loss. DESIGN AND SETTING Randomised controlled trial (ISRCTN85485463) in UK primary care during 2007-2008. METHOD Adults with a BMI of 27-35 kg/m2 and ≥1 risk factor for obesity-related disease were randomised to attend a community weight loss programme (n = 45) or receive usual weight loss advice from a practice nurse (n = 28). Weight and the ELF score were measured at baseline and 1 year. Analysis of covariance examined mean changes in the ELF score between groups and its relationship with weight loss. RESULTS Mean (SD) BMI was 31.10 kg/m2 (2.55) with evidence of moderate levels of liver fibrosis at baseline (mean ELF score: 8.93 [0.99]). There was no evidence that the community weight loss programme reduced the ELF score compared with usual care (difference +0.13 points, 95% CI: -0.25 to 0.52) despite greater weight loss (difference: -2.66 kg, 95% CI: -5.02 to -0.30). Mean weight loss in the whole cohort was 7.8% (5.9). There was no evidence of an association between weight change and change in ELF; the coefficient for a 5% weight loss was -0.15 (95% CI: -0.30 to 0.0002). CONCLUSION We found no evidence that the ELF score changed meaningfully following moderate weight loss. Clinicians should not use the ELF score to measure improvements in NAFLD fibrosis following weight loss programmes.
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Total and Subtypes of Dietary Fat Intake and Its Association with Components of the Metabolic Syndrome in a Mediterranean Population at High Cardiovascular Risk.
Julibert, A, Bibiloni, MDM, Bouzas, C, Martínez-González, MÁ, Salas-Salvadó, J, Corella, D, Zomeño, MD, Romaguera, D, Vioque, J, Alonso-Gómez, ÁM, et al
Nutrients. 2019;11(7)
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Obesity, Metabolic Syndrome (MetS) and Cardiovascular Disease (CVD) are becoming a global epidemic and the role of dietary fats is still unclear. The PREDIMED trial is a large study of 6560 Mediterranean men and women, aged 55–75 years old, with overweight/obesity and MetS in which they have tracked all types of dietary fat consumed over a 6-year period to assess the risk factors for CVD. Quality of fat is thought to play an important role in MetS. This study used food questionnaires to measure intake of the following fats: total fat, monounsaturated fatty acids: MUFA, polyunsaturated fatty acids: PUFA, saturated fatty acids: SFA, trans-fatty acids: trans-FA, linoleic acid, a-linolenic acid, and w-3 FA). They were able to divide the participants into groups ranging from highest to lowest fat intake and assess the types of foods and fats being consumed. They found that the group with the highest fat intakes ate less carbohydrates, protein and fibre and had a higher risk of hyperglycaemia (high blood glucose levels). The total fats consumed in this group also included high levels of harmful trans-fatty acids so the researchers concluded that the risk is influenced by the combination of nutrients of the food consumed. They also found that participants who consumed high levels of linoleic acid had significantly higher healthy HDL cholesterol levels and those who consumed high levels of saturated fatty acids and omega 3 had significantly less risk of high triglycerides (another cholesterol marker). Overall they recommend further studies into types of dietary fat to help reduce MetS in the population.
Abstract
Background: The effect of dietary fat intake on the metabolic syndrome (MetS) and in turn on cardiovascular disease (CVD) remains unclear in individuals at high CVD risk. Objective: To assess the association between fat intake and MetS components in an adult Mediterranean population at high CVD risk. Design: Baseline assessment of nutritional adequacy in participants (n = 6560, men and women, 55-75 years old, with overweight/obesity and MetS) in the PREvención con DIeta MEDiterránea (PREDIMED)-Plus randomized trial. Methods: Assessment of fat intake (total fat, monounsatured fatty acids: MUFA, polyunsaturated fatty acids: PUFA, saturated fatty acids: SFA, trans-fatty acids: trans-FA, linoleic acid, α-linolenic acid, and ω-3 FA) using a validated food frequency questionnaire, and diet quality using 17-item Mediterranean dietary questionnaire and fat quality index (FQI). Results: Participants in the highest quintile of total dietary fat intake showed lower intake of energy, carbohydrates, protein and fiber, but higher intake of PUFA, MUFA, SFA, TFA, LA, ALA and ω-3 FA. Differences in MetS components were found according to fat intake. Odds (5th vs. 1st quintile): hyperglycemia: 1.3-1.6 times higher for total fat, MUFA, SFA and ω-3 FA intake; low high-density lipoprotein cholesterol (HDL-c): 1.2 higher for LA; hypertriglyceridemia: 0.7 lower for SFA and ω-3 FA intake. Conclusions: Dietary fats played different role on MetS components of high CVD risk patients. Dietary fat intake was associated with higher risk of hyperglycemia.
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Effect of a Nutritional and Behavioral Intervention on Energy-Reduced Mediterranean Diet Adherence Among Patients With Metabolic Syndrome: Interim Analysis of the PREDIMED-Plus Randomized Clinical Trial.
Sayón-Orea, C, Razquin, C, Bulló, M, Corella, D, Fitó, M, Romaguera, D, Vioque, J, Alonso-Gómez, ÁM, Wärnberg, J, Martínez, JA, et al
JAMA. 2019;322(15):1486-1499
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Excess caloric intake and poor nutritional quality are associated with overweight and obesity. A traditional Mediterranean diet has been shown to reduce all-cause mortality, and in particular to reduce risk of cardiovascular disease, type 2 diabetes mellitus and overweight. The aim of this randomised, prospective, single-blinded study was to evaluate the effectiveness of an intensive lifestyle intervention programme in 6874 overweight or obese men and women with metabolic syndrome in Spain. The intervention group was advised on an energy-reduced Mediterranean diet and exercise and received behavioural support, with initial group sessions and interviews, and monthly follow-up phone calls for one year. The control group received advice on a Mediterranean diet and usual care, with 6 monthly follow-ups. After 12 months, the more intensively counselled patients showed a significantly better adherence to an energy-reduced Mediterranean diet than the control group. They had greater reductions in refined grains, pastries, red and processed meats and greater increases in vegetable, fruit and nut consumption than the control group. The intervention group had also better improvements in cardiovascular risk factors.
Abstract
Importance: High-quality dietary patterns may help prevent chronic disease, but limited data exist from randomized trials about the effects of nutritional and behavioral interventions on dietary changes. Objective: To assess the effect of a nutritional and physical activity education program on dietary quality. Design, Setting, and Participants: Preliminary exploratory interim analysis of an ongoing randomized trial. In 23 research centers in Spain, 6874 men and women aged 55 to 75 years with metabolic syndrome and no cardiovascular disease were enrolled in the trial between September 2013 and December 2016, with final data collection in March 2019. Interventions: Participants were randomized to an intervention group that encouraged an energy-reduced Mediterranean diet, promoted physical activity, and provided behavioral support (n = 3406) or to a control group that encouraged an energy-unrestricted Mediterranean diet (n = 3468). All participants received allotments of extra-virgin olive oil (1 L/mo) and nuts (125 g/mo) for free. Main Outcomes and Measures: The primary outcome was 12-month change in adherence based on the energy-reduced Mediterranean diet (er-MedDiet) score (range, 0-17; higher scores indicate greater adherence; minimal clinically important difference, 1 point). Results: Among 6874 randomized participants (mean [SD] age, 65.0 [4.9] years; 3406 [52%] men), 6583 (96%) completed the 12-month follow-up and were included in the main analysis. The mean (SD) er-MedDiet score was 8.5 (2.6) at baseline and 13.2 (2.7) at 12 months in the intervention group (increase, 4.7 [95% CI, 4.6-4.8]) and 8.6 (2.7) at baseline and 11.1 (2.8) at 12 months in the control group (increase, 2.5 [95% CI, 2.3-2.6]) (between-group difference, 2.2 [95% CI, 2.1-2.4]; P < .001). Conclusions and Relevance: In this preliminary analysis of an ongoing trial, an intervention that encouraged an energy-reduced Mediterranean diet and physical activity, compared with advice to follow an energy-unrestricted Mediterranean diet, resulted in a significantly greater increase in diet adherence after 12 months. Further evaluation of long-term cardiovascular effects is needed. Trial Registration: isrctn.com Identifier: ISRCTN89898870.
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A 12-Month Lifestyle Intervention Program Improves Body Composition and Reduces the Prevalence of Prediabetes in Obese Patients.
König, D, Hörmann, J, Predel, HG, Berg, A
Obesity facts. 2018;11(5):393-399
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Obesity and its impact on the prevalence of diabetes and subsequent cardiovascular disease is one of the major health burdens in Western societies. Lifestyle intervention studies have shown that weight loss combined with increased physical activity can improve metabolic risk factors. The aim of this study was to evaluate the effect of a comprehensive lifestyle intervention programme on weight and metabolic risk factors in 5884 obese individuals. The programme included 61 sessions over 12 months, including 41 exercise sessions, 12 psychological/self-management sessions and 8 nutritional counselling sessions (based on a low glycaemic index, low fat diet). After 12 months there was a significant reduction in weight (average 6%), waist circumference, physical fitness and all metabolic parameters (including blood sugar and fat metabolism). Overall, in 839 (38%) of the 2,227 participants who were pre-diabetic before intervention, the criteria of pre-diabetes were no longer detectable after 12 months, whilst only 66 (3%) progressed to type 2 diabetes mellitus. 46.7% of the 1,641 participants fulfilling the criteria of metabolic syndrome before the intervention, did not show any signs of this syndrome after the intervention; whilst only 120 participants (+7.3%) newly developed metabolic syndrome. The authors concluded that the intensive lifestyle intervention programme was successful, even in obese people with pre-diabetes.
Abstract
BACKGROUND The present study investigated the effects of a 12-month interdisciplinary standardized lifestyle program addressing physical activity and changes in dietary and lifestyle behavior in 2,227 obese prediabetic participants. METHODS Measures of obesity (BMI, waist circumference), cardiopulmonary fitness, and metabolic parameters were determined before and after the intervention period. RESULTS From the 2,227 participants who were initially prediabetic, 839 participants (-37.7%) did no longer show the criteria of prediabetes after the intervention and had normal HbA1c levels. CONCLUSION The clinical effects are substantial, and it is likely that the applied intense and multidisciplinary lifestyle interventions could reduce the risk of developing diabetes and the prevalence of a full-blown metabolic syndrome in obese and prediabetic patients.
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Men and women respond differently to rapid weight loss: Metabolic outcomes of a multi-centre intervention study after a low-energy diet in 2500 overweight, individuals with pre-diabetes (PREVIEW).
Christensen, P, Meinert Larsen, T, Westerterp-Plantenga, M, Macdonald, I, Martinez, JA, Handjiev, S, Poppitt, S, Hansen, S, Ritz, C, Astrup, A, et al
Diabetes, obesity & metabolism. 2018;20(12):2840-2851
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Overweight and obesity are major risk factors for developing type 2 diabetes mellitus. Men and women respond differently to weight loss programmes, with men typically losing more weight and more abdominal fat, whilst women lose more subcutaneous fat. The aim of this large multinational study was to compare the effects of weight loss induced by an 8‐week low energy diet on metabolic outcomes in overweight men and women with prediabetes. Study participants followed the Cambridge Weight Plan which is based on four formula meals, with a total of approximately 810kcal, per day, for eight weeks. Small amounts of non-starchy vegetables were allowed, as were psyllium husks in case of digestive problems. Men lost significantly more weight than women, 11.8% versus 10.3%. Insulin resistance improved similarly in men and women, but metabolic syndrome score improved more in men than in women. Men lost more fat than women and generally had more beneficial metabolic changes. Women had higher reductions in fat-free mass, bone mineral content and HDL cholesterol than men, raising the question whether rapid weight loss may have negative longer term effects for women.
Abstract
AIMS: The PREVIEW lifestyle intervention study (ClinicalTrials.gov Identifier: NCT01777893) is, to date, the largest, multinational study concerning prevention of type-2 diabetes. We hypothesized that the initial, fixed low-energy diet (LED) would induce different metabolic outcomes in men vs women. MATERIALS AND METHODS All participants followed a LED (3.4 MJ/810 kcal/daily) for 8 weeks (Cambridge Weight Plan). Participants were recruited from 8 sites in Europe, Australia and New Zealand. Those eligible for inclusion were overweight (BMI ≥ 25 kg/m2 ) individuals with pre-diabetes according to ADA-criteria. Outcomes of interest included changes in insulin resistance, fat mass (FM), fat-free mass (FFM) and metabolic syndrome Z-score. RESULTS In total, 2224 individuals (1504 women, 720 men) attended the baseline visit and 2020 (90.8%) completed the follow-up visit. Following the LED, weight loss was 16% greater in men than in women (11.8% vs 10.3%, respectively) but improvements in insulin resistance were similar. HOMA-IR decreased by 1.50 ± 0.15 in men and by 1.35 ± 0.15 in women (ns). After adjusting for differences in weight loss, men had larger reductions in metabolic syndrome Z-score, C-peptide, FM and heart rate, while women had larger reductions in HDL cholesterol, FFM, hip circumference and pulse pressure. Following the LED, 35% of participants of both genders had reverted to normo-glycaemia. CONCLUSIONS An 8-week LED induced different effects in women than in men. These findings are clinically important and suggest gender-specific changes after weight loss. It is important to investigate whether the greater decreases in FFM, hip circumference and HDL cholesterol in women after rapid weight loss compromise weight loss maintenance and future cardiovascular health.
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Improvement of Nonalcoholic Fatty Liver Disease With Carnitine-Orotate Complex in Type 2 Diabetes (CORONA): A Randomized Controlled Trial.
Bae, JC, Lee, WY, Yoon, KH, Park, JY, Son, HS, Han, KA, Lee, KW, Woo, JT, Ju, YC, Lee, WJ, et al
Diabetes care. 2015;38(7):1245-52
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Non-alcoholic fatty liver disease (NAFLD) is recognized as the hepatic component of metabolic syndrome, and it is associated with insulin resistance independent of obesity and other metabolic components. Carnitine is a modulator of mitochondrial free fatty acid transport and oxidation, and several studies have demonstrated the antioxidant activity of carnitine in hepatocytes. The aim of this study was to evaluate the effects of carnitine-orotate complex in patients with NAFLD and diabetes. This study is a multicentre, randomised, double-blind, placebo-controlled trial. Patients were randomly assigned to receive carnitine-orotate complex or placebo during the 12-week treatment period. Results show that treatment with carnitine-orotate complex improves hepatic steatosis in patients with diabetes and NAFLD, and has a beneficial effect on glucose metabolism, particularly in relation to improvement of hepatic steatosis. Authors conclude that further studies using more advanced magnetic resonance imaging and liver histology as an end point are needed to assess its efficacy in NAFLD.
Abstract
OBJECTIVE We aimed to evaluate the effects of carnitine-orotate complex in patients with nonalcoholic fatty liver disease (NAFLD) and diabetes. RESEARCH DESIGN AND METHODS Eight hospitals in Korea participated in this randomized, controlled, double-blind trial of patients with diabetes and NAFLD. Seventy-eight patients were randomly assigned in a 1:1 ratio to receive carnitine-orotate complex (824 mg, three times daily) or matching placebo. The primary study outcome was decline in alanine aminotransferase (ALT) to the normal range. Secondary study outcomes were change in ALT, radiological hepatic steatosis, parameters for anthropometry, liver function, lipid profiles, and glycemic control. Hepatic steatosis was assessed using Hounsfield units on noncontrast computed tomography (CT) imaging with hepatic attenuation. RESULTS After 12 weeks of treatment, compared with placebo group, carnitine-orotate complex-treated participants had a significantly higher rate of normalization of serum ALT level (17.9% vs. 89.7%, P < 0.001). On hepatic CT analysis, participants treated with carnitine-orotate complex showed an increased liver attenuation index (0.74 ± 8.05 vs. 6.21 ± 8.96, P < 0.008). A significant decrease in HbA1c was observed in the carnitine-orotate complex group (-0.33 ± 0.82% [-3.6 ± 9.0 mmol/mol], P = 0.007), but no significant change was seen in the placebo group. CONCLUSIONS Treatment with carnitine-orotate complex improves serum ALT and may improve hepatic steatosis as assessed by CT in patients with diabetes and NAFLD. Further studies using more advanced magnetic resonance imaging and liver histology as an end point are needed to assess its efficacy in NAFLD.
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Mediterranean dietary pattern and depression: the PREDIMED randomized trial.
Sánchez-Villegas, A, Martínez-González, MA, Estruch, R, Salas-Salvadó, J, Corella, D, Covas, MI, Arós, F, Romaguera, D, Gómez-Gracia, E, Lapetra, J, et al
BMC medicine. 2013;11:208
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The role of diet in preventing mental disorders has been increasingly explored in the past few years. Few observational studies have associated the traditional Mediterranean diet (MD) with a reduced risk of depression, however this available information is limited and inconclusive. The aim of this trial was to compare the efficacy of two variations of the MD on depression among patients at high risk of cardiovascular disease. The diets included MD supplemented with extra-virgin olive oil or mixed nuts, and a control group advised to follow a low-fat diet. The study included 3923 participants aged 55-80 the median follow-up was 5.4 years. The findings of this trial did not show a significant decrease in depression risk among participants assigned to either MD group compared with the control. However when the specific cohort of subjects with type 2 diabetes was analysed, the depression risk was significantly reduced compared with the control group. Based on this study, the authors suggest a beneficial effect of the MD on depression for patients with type 2 diabetes though further investigation is required.
Abstract
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. TRIAL REGISTRATION This trial has been registered in the Current Controlled Trials with the number ISRCTN 35739639.
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Primary prevention of cardiovascular disease with a Mediterranean diet.
Estruch, R, Ros, E, Salas-Salvadó, J, Covas, MI, Corella, D, Arós, F, Gómez-Gracia, E, Ruiz-Gutiérrez, V, Fiol, M, Lapetra, J, et al
The New England journal of medicine. 2013;368(14):1279-90
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The traditional Mediterranean diet has been shown to have cardiovascular protective effects based on previous observational cohort studies and a secondary prevention trial. While the mechanism for the beneficial effects of this diet have not been established, small trials have suggested that it fosters favourable changes in the pathways involved in cardio-metabolic disease. The aim of this randomised trial was to test the efficacy of two variations of the Mediterranean diet on reducing the incidence of cardiovascular events. These diets included Mediterranean diet supplemented with extra-virgin olive oil or mixed nuts, and a control diet (advised to reduce dietary fat). The study included 7,447 participants aged 55-80 and participants were followed for an average of 4.8 years. Both groups showed good adherence to the diets. The findings of this study showed that among persons at high cardiovascular risk, both variations of the Mediterranean diet resulted to a significant risk reduction of cardiovascular events, notably stroke. Based on this study, the authors’ conclusions support the benefits of the Mediterranean diet for the primary prevention of cardiovascular disease.
Abstract
BACKGROUND Observational cohort studies and a secondary prevention trial have shown an inverse association between adherence to the Mediterranean diet and cardiovascular risk. We conducted a randomized trial of this diet pattern for the primary prevention of cardiovascular events. METHODS In a multicenter trial in Spain, we randomly assigned participants who were at high cardiovascular risk, but with no cardiovascular disease at enrollment, to one of three diets: a Mediterranean diet supplemented with extra-virgin olive oil, a Mediterranean diet supplemented with mixed nuts, or a control diet (advice to reduce dietary fat). Participants received quarterly individual and group educational sessions and, depending on group assignment, free provision of extra-virgin olive oil, mixed nuts, or small nonfood gifts. The primary end point was the rate of major cardiovascular events (myocardial infarction, stroke, or death from cardiovascular causes). On the basis of the results of an interim analysis, the trial was stopped after a median follow-up of 4.8 years. RESULTS A total of 7447 persons were enrolled (age range, 55 to 80 years); 57% were women. The two Mediterranean-diet groups had good adherence to the intervention, according to self-reported intake and biomarker analyses. A primary end-point event occurred in 288 participants. The multivariable-adjusted hazard ratios were 0.70 (95% confidence interval [CI], 0.54 to 0.92) and 0.72 (95% CI, 0.54 to 0.96) for the group assigned to a Mediterranean diet with extra-virgin olive oil (96 events) and the group assigned to a Mediterranean diet with nuts (83 events), respectively, versus the control group (109 events). No diet-related adverse effects were reported. CONCLUSIONS Among persons at high cardiovascular risk, a Mediterranean diet supplemented with extra-virgin olive oil or nuts reduced the incidence of major cardiovascular events. (Funded by the Spanish government's Instituto de Salud Carlos III and others; Controlled-Trials.com number, ISRCTN35739639.).