lyon diet heart study

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http://www.facebook.co m/pronutritionist Lyon Diet Heart Study Mediterranean diet vs “traditional” western diet Published as two separate papers: de Lorgeril et al . Mediterranean diet, traditional risk factors, and the rate of cardiovascular complications after myocardial infarction: final report of the Lyon Diet Heart Study. Circulation. 1999; 99(6):779-85 de Lorgeril et al . Mediterranean alpha-linolenic acid-rich diet in secondary prevention of coronary heart disease. Lancet 1994; 343(8911):1454-9 1 Original paper: 27 months of randomization 2 Follow up of 46 months’s

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Lyon Diet Heart Study is still considered as the ultimate evidence for the health benefits of Mediterranean diet. Unfortunately its' results have never been re-produced since then. However, PREDIMED trial may change this situation.

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Page 1: Lyon Diet Heart Study

http://www.facebook.com/pronutritionist

Lyon Diet Heart StudyMediterranean diet vs “traditional” western diet

Published as two separate papers:

de Lorgeril et al. Mediterranean diet, traditional risk factors, and the rate of cardiovascular complications after myocardial infarction: final report of the

Lyon Diet Heart Study. Circulation. 1999; 99(6):779-85

de Lorgeril et al. Mediterranean alpha-linolenic acid-rich diet in secondary prevention of coronary heart disease. Lancet 1994;

343(8911):1454-9

1 Original paper: 27 months of randomization

2 Follow up of 46 months’s

Page 2: Lyon Diet Heart Study

Page 2

Pronutritionist’s background

• In recent prospective cohorts based meta-analyses, saturated fat intake was not linked to coronary heart disease (CHD) incidence (Siri-Tarino et al. 2010, Skeaff  & Miller J. 2009 and Mente et al. 2009)

• Another meta-analysis based on 48 randomized outcome trials, demonstrated a lower incidence of CHD if saturated fat was replaced by unsaturated fat or reduced (Hooper et al. 2011)

• However, a majority of the studiesare done during 1960s and 1970s, used either soy, corn or safflower oil. All of these cooking oils have been largely replaced by olive or canola (or turnip rapeseed) oil in recent years, at least in many Nordic and Western European countries

• No hard outcome data exists for either canola or olive oil in clinical trials scrutinizing the sole effect of displacement of saturated fat with canola oil

• In Lyon Diet Heart Study (LDHS) canola oil was used as an integrative part of Mediterranean diet model

• How do the results of LDHS stand the test of the time?

de Lorgeril et al.. Lancet 1994; 343(8911):1454-9

Page 3: Lyon Diet Heart Study

Methods (schematic)

Page 3

Randomization

Experimental diet Mediterranean diet including free canola oil based margarine

Control diet normal French Diet

27 months randomized period

y. 1988

19 months open follow up (delay in stopping)

Premature discontinuation (!)

de Lorgeril et al.. Lancet 1994; 343(8911):1454-9

Page 4: Lyon Diet Heart Study

Methods (patients)• Parallel randomized trial, Single blinded

• Secondary prevention of CHD among myocardial infarction (MI) survivors

• Primary outcomes: Reinfarctions and cardiac death

• Secondary outcomes: Coronary bypass surgery, angioplasty, and their complications, stroke, angina, heart failure, pulmonary/venous embolism, thrombophlebitis

• N=605, circa 90 % were males, median age 53,5 years

• Slightly more than 60 % of the patients received beta-blockers and ASA. Statins were not prescribed

• Recruitment: during the hospitalization due to MI

• LDL cholesterol levels at baseline in both groups circa 4,5 mmol/L (175 mg/dl)

• Subjects were free living• Length: 5 years per arm (!) but was discontinued prematurely at 27 months

due to excessive morbidity/mortality rate in control group (”Because of a statistically significant result, the decision was made to stop the trial.” deLoergeril et al. 1999)

• Era: 1988 →

Page 4 de Lorgeril et al.. Lancet 1994; 343(8911):1454-9

Page 5: Lyon Diet Heart Study

Methods (diet)• Experimental Diet = Cretan style Mediterranean diet• Patients in the experimental group were advised by the research cardiologist and dietitian (a one-hour-

long session)• Mediterranean-type diet:

– more bread– more root vegetables and green vegetables– more fish, less meat (beef, lamb, and pork to be replaced with poultry)– No day without fruit– Butter and cream to be replaced with margarine supplied by the study. ”This margarine had a composition comparable to olive

oil with 15 % saturated fatty acids, 48% oleic acid but 5-4% 18:1 trans. However, it was slightly higher in linoleic (16-4 vs 8-6%) and more so in alpha-linolenic acid (4-8 vs 0-6%)”

– The oils recommended for salads and food preparation were rapeseed and olive oils exclusively. – Moderate alcohol consumption in the form of wine was allowed at meals.

• At each subsequent visit of the experimental patients, a dietary survey and further counselling were done by the research dietitian. Diet evaluations comprised a 24-hour recall and frequency questionnaire.

*) Serum Cholesterol Lowering Diet

Page 5 de Lorgeril et al.. Lancet 1994; 343(8911):1454-9

Page 6: Lyon Diet Heart Study

Results 1/5 (27 months randomization)

• Totally 584 subjects were analyzed

• Drop out rate was low, ie. 7-8 % (patients who did not attend two consecutive appointments)

• Dietary intake and biochemical parameters was analyzed in 411 patients (70 % of all)

• There were no differences in baseline characteristics of patients

• There was no difference in the degree of attention or care given to the study groups (verified by separate survey)

• At the end of the study, number of smokers was higher in Mediterranean group

• Study was discontinued prematurely due to excessive morbidity/mortality rate in control group

Page de Lorgeril et al.. Lancet 1994; 343(8911):1454-9

Page 7: Lyon Diet Heart Study

Results 2/5 (27 months randomization)

Page 7

Mediterranean diet Control French Diet Δ significance

Energy 1928 kcal 2140 kcal p< 0.001

SFA 8.3 E % 11.7 E % p< 0.001

Oleic acid 12.9 E % 10.3 E % p< 0.001

Linoleic acid 3.6 E % 5.3 E % p< 0.001

α –linolenic acid 0.81 E % 0.27 E % p< 0.001

Cholesterol 217 mg 318 mg p< 0.001

Carbohydrates* 52.3 E % 50.8 E % N/A

Protein 17.2 E % 16.5 E % P=0.12

Fat 30.5 E % 32.7 E % P=0.008

Fiber N/A N/A N/A

Trans fat** N/A N/A N/A

Dietary changes (at 1-4 years)

*) Not given, calculated **) Trans fat content of serum lipids did not differ between groups

de Lorgeril et al.. Lancet 1994; 343(8911):1454-9

Page 8: Lyon Diet Heart Study

Results 3/5 (27 months randomization)

Page 8

Mediterranean diet

Control French Diet

Baseline value(MedDiet/Ctrl)

Weight +1 kg +3 kg 74/73

Systolic blood pressure + 7 mmHg + 9 mmHg 120/119

Diastolic blood pressure + 4 mmHg + 5 mmHg 74/74

Triglycerides -0.15 mmol/L -0.23 mmol/L 2.0/2.15

LDL -0,36 mmol/L -0.43 mmol/L 4.52/4.54

HDL + 0.16 mmol/L + 0.11 mmol/L 1.16/1.17

Changes in cardiovascular risk factors vs baseline (at 104 weeks)

Note! • There were no significant differences between groups• Serum antioxidant levels were higher in Med Diet group

de Lorgeril et al.. Lancet 1994; 343(8911):1454-9

Page 9: Lyon Diet Heart Study

Results 4/5 (27 months randomization)

Page 9

Deaths and cardiovascular end points (number of events)

P=0.02

Δ - 73 % (adjusted)

P=0.02

P=0.001

Δ - 76 % (adjusted)

Δ - 70 % (adjusted)

de Lorgeril et al.. Lancet 1994; 343(8911):1454-9

Page 10: Lyon Diet Heart Study

Results 5/5 (follow up results up 4 years)

Page 10 de Lorgeril et al.. Circulation 1999; 99(6):779-85

preceding plus minor events requiring hospital admission, including recurrent stable angina, restenosis etc. -47 % (CO 3)

Myocardial infarction plus cardiovascular death plus major secondary events -67 %(CO 2).

Myocardfial infarction plus cardiovascular death -72 % (CO 1)

Note! Addtionally reported in this paper: - Fiber intake: 18,6 g/ 15,5 g/day-Lipid Lowering Drugs 26,5 % vs 34 %

(Med Diet vs Controls)

Page 11: Lyon Diet Heart Study

Pronutritionist’s discussion (1/5)

• In my knowledge, LDHS delivered best-ever results in reducing cardiovascular events in randomized dietary trial

• Remarkably, the results are not explained by any difference in LDL cholesterol between the groups (4,2 vs 4.3 mmol/L)

• Authors interestingly point out that the high linoleic acid intake (such as in classic outcome RCTs) is associated with platelet-induced aggregation and lipid peroxidation.

• The magnitude of the displacement of SFA with margarine was circa 5 % of daily energy intake (15 grams of butter was replaced with margarine) and was associated with null difference in LDL cholesterol

• In a recent meta-analysis by Mozaffarian (2010), 5 E % replacement of SFA with PUFA was 10 % reduction CHD events. However, in Lyon Heart Study the outcomes were not driven by any changes in cholesterol, and even more interestingly, the intake of PUFA was lower in Mediterranean Diet group than in control group (4.6 E % vs 6.1 E %, p=0,0001, 4 year results)

• Most striking dietary difference was α –linolenic acid intake (0.81 E % in MedDiet vs 0.27 E % in controls)

Page 11 de Lorgeril et al. 1994; de Lorgeril et al. 1999

Page 12: Lyon Diet Heart Study

Pronutritionist’s discussion (2/5)Strengths of Lyon Diet Heart Study

Page 12

• Randomized trial with free supplementation of margarine. Feeding of any food item is likely to improve compliance to diet (which is notoriously poor in long term trials)

• Diets were relatively well reported, even if fiber intake was reported only at 4 years (15.5 g/day in controla and 18.6g/day in Mediterranean group p= 0.004)

• Medical attention is likely to have been quite similar in between the groups

• Drop out is very low at 27 months (≤ 8 %)

• Well documented end points

• Well documented medications

de Lorgeril et al. 1994; de Lorgeril et al. 1999

Page 13: Lyon Diet Heart Study

Pronutritionist’s discussion (3/5)Weaknesses of Lyon Diet Heart Study

Page 13

• Glucose levels of patients were neither monitored nor reported. It is not known if incidence of diabetes or IGT was equally distributed among groups

• A small difference in weight gain between the groups favoring active group

• The changes is dietary intakes were modest or even subtle, and underlining the importance of free supplementation

• The mechanistic model behind the observed effects is vague (platelet-induced aggregation and lipid peroxidation) and inadequately proven in later trials. For example, latest meta-analyses on omega-3 fatty acid supplementation have demonstrated modest or disappointing results (Chen et al. 2011 )

• Currently, statins are routinely prescribed to MI survivors. It is not known if Lyon Diet would yield good results on top of widely prescribed statin treatment. In omega- 3 trials, the effect of omega-3 supplementation is only seen among those who do not use statins and other modern MI drugs (Chen et al. 2011 )

• The results have not been re-produced in any other long-term outcome trial

de Lorgeril et al. 1994; de Lorgeril et al. 1999

Page 14: Lyon Diet Heart Study

Pronutritionist’s discussion (4/5)Contrasting Lyon and Oslo Diet Heart

Lyon Heart Study ACTIVE TREATMENT

Oslo Diet HeartACTIVE TREATMENT

Linoleic acid intake (omega-6 FA intake)

↓ (rather low circa 4 E %) ↑ (very high, circa 15 E %)

α –linolenic acid ↑ ( circa 0,8 E %) ↑ ( circa 2,7 E %, Ramsden et al. 2010)

Trans fat ↑(as margarine, circa 1 g/d)

↓(Hard margarine was prohibited)

Marine omega-3 fatty acids ↑ (due to promotion of fish) ↑↑ (due to supplementation of sardines)

Fiber ↑ ↑ *

SFA ↓ ↓

Vitamin D No change ↑**

Total PUFA ↓ ↑

Antioxidants/(Polyphenols) ↑ ↑

Page 14 http://www.facebook.com/pronutritionist

*) not reported but likely as brown bread, vegetables and fruit were promoted), **) free sardines in cod liver oil, intake of vitamin estimated to be circa 15 mcg/day (Ramsden et al. 2010)

de Lorgeril et al. 1994; de Lorgeril et al. 1999

Page 15: Lyon Diet Heart Study

Pronutritionist’s discussion (5/5)Conclusion

• LHS delivered robust results without any difference in LDL, HDL or triglycerides

• LHS and Oslo Diet-Heart are very alike:

– Both were multi-factorial meal pattern trials where subjects were given food items for free

– Both trials had emphasis on increasing omega-3 fatty acids, fish instead of meat, fruit/vegetables, whole grains, and oils in cooking.

– But these trials also demonstrate that not one bad single dietary change can dilute positive effects of comprehensive dietary modification (very high linoleic acid intake in Oslo Diet-Heart, trans fat intake in Lyon heart study)

• Background diet in LHS is much closer to current one than in any other large fat displacement trials

• The LHS is still considered as the ultimate evidence for the health benefits of Mediterranean diet. The results have not been reproduced since Lyon Heart Study. PREDIMED trial will soon show if the effects of Mediterranean diet can be re-produced

Page 15 http://www.facebook.com/pronutritionist

de Lorgeril et al. 1994; de Lorgeril et al. 1999

Page 16: Lyon Diet Heart Study

Read also about Oslo Diet-Heart Study

& Predimes Study

www.pronutritionist.net16

Page 17: Lyon Diet Heart Study

Welcome aboard

11/04/2317

http://twitter.com/pronutritionisthttp://www.facebook.com/pronutritionisthttp://www.pronutritionist.net (Finnish)

http://www.pronutritionistblog.com (English)

Reijo Laatikainen, Registered dietitian, MSc MBA