One mainstay in treating heart failure (HF) is in minimizing risk factors.1 Controlling hypertension, dyslipidemia, obesity, and diabetes mellitus are important for people in all stages of heart failure.1,2 A healthy diet is critical for preventing or managing all these conditions. Sodium restriction is also recommended for people with HF to reduce congestive symptoms, particularly for people with: 1,3
- Stage C or D HF
- Structural heart disease and prior or current HF symptoms
- End-stage for refractory HF
The United States Department of Agriculture (USDA) and Department of Health and Human Services (HHS) dietary guidelines4recommends a diet that consists of nutrient dense foods from various food groups (vegetables, fruits, protein, dairy, grains, oils) within an appropriate calorie level and limiting foods that contain saturated or trans fats, added sugars and sodium.
The Mediterranean diet has the most evidence to support its recommendation for patients with heart failure. Other “heart-healthy” diets recommended for the prevention or management of hypertension and hypercholesteremia including the Dietary Approaches to Stop Hypertension (DASH) diet; however, more studies are needed before it should be recommended specifically for people with symptomatic HF.5,6
Mediterranean Diet
The Mediterranean diet was initially described in 1993 by the Harvard School of Public Health, Oldways Preservation and Exchange Trust, and the European Office of the World Health Organization as a guide to traditional foods common to the countries that border the Mediterranean Sea during the mid-20th century where higher than average adult life expectancy and lower rates of chronic disease were noted.7 This is a primarily plant-based diet with an emphasis on whole grains, olive oils, and nuts. Animal products (preference for fish and seafood) are consumed in small quantities. Studies have shown that this diet is effective at reducing both the risk of cardiovascular disease and overall mortality in individuals with or without known cardiovascular disease.8,9 Notably, the PREDIMED study, a primary prevention randomized control trial (RCT), examined the effect of a Mediterranean diet on cardiovascular events like myocardial infarction or stroke, and death from cardiovascular causes. This trial enrolled 7447 participants (age 55 to 80) with no pre-existing cardiovascular disease, who either had diabetes or three major risk factors for cardiovascular disease such as smoking, hypertension, elevated cholesterol, obesity, or family history of premature coronary heart disease to one of three diets: 1) a Mediterranean diet supplemented with extra-virgin olive oil, 2) a Mediterranean diet supplemented with mixed nuts, or 3) a control diet (patients were advised to reduce dietary fat). Over a 5-year period they found that participants who received the Mediterranean diet had reduced rates of cardiovascular events by 30% over a 5-year period as compared to the control group (low-fat diet).10
In contrast, a study led by Papadaki et al. examined the impact of the Mediterranean diet on the incidence of HF, which was a pre-specified secondary outcome of PREDIMED. Investigators found no association between the Mediterranean diet and the incidence of HF as compared with the control group.11 Results should be interpreted with caution, however, since this secondary analysis may have been underpowered.
Dietary Sodium Restriction
Dietary sodium restriction is often recommended for patients with HF by many guidelines.1,3 However the data upon which this recommendation is based is modest, at best, and the optimal level of sodium intake is not clear.1,3,12 It is challenging to synthesize salt studies in HF as many vary with respect to protocol compliance, amount of fluid, and sodium intake. In their 2018 Systematic review, Mahtani et al. found there to be limited evidence on the efficacy of reduced dietary salt intake in the outpatient setting among HF patients.12
The rationale behind sodium reduction in HF is based upon observational data which has demonstrated that increased dietary sodium intake is associated with a higher risk of cardiac events.1,13 A prospective observational study by Tuomilehto et al. of over 2,000 adults examined the association between 24-hour urine sodium excretion and incident cardiovascular disease as well as cardiovascular and all-cause mortality. Overall, after adjustment for demographic characteristics, cholesterol levels, blood pressure and body mass index, the hazard ratio for the association between 24-hour urine sodium excretion and coronary heart disease was found to be 1.56 (CI 1.15-2.12), while that for cardiovascular mortality was 1.36 (1.05-1.76), indicating that sodium intake may contribute to adverse cardiovascular health beyond its impact on cardiovascular risk factors such as blood pressure. Additionally, a study of 10,362 community dwelling adults through the National Health and Nutrition Examination Survey found that sodium intake was significantly associated with risk of incident congestive HF but only in overweight individuals, suggesting that certain individuals may be more sodium sensitive than others.14
Some RCTs have shown an association with lower sodium intake with worse outcomes in individuals with HFrEF.1,3,15 In the multihospital HF Adherence and Retention Trial, patients with NYHA class II and III were followed for a median of 36 months.15 In this trial, participants in the sodium restricted group (<2500 mg/day) had significantly higher rates of HF hospitalization (HR 1.82, 95% CI [1.11 – 2.96], p=0.015)) and a nonsignificant increase in cardiac death (HR 1.62, 95% CI [0.70 – 3.73, p=0.257) and all-cause mortality (HR 1.62, 95% CI [0.94 – 3.53,] p=0.074) compared to participants in the unrestricted sodium (≥2500 mg/day) group.
Overall, the American College of Cardiology and American Heart Association 2013 guidelines for the management of HF recommend that a low salt diet should vary depending on the type of HF, disease severity, HF comorbidities, and other patient specific factors.1 The guidelines recommend restriction of sodium to 1500 mg/day for most patients with Stage A and B HF as there is a clear association between high sodium intake and the development of hypertension, cardiovascular disease, and LV hypertrophy. However, they note that there is insufficient data to specify a particular level of sodium intake for those with more advanced HF (Stage C or D).1 They suspect <3 g a day may be reasonable to reduce congestive symptoms. The European Society of Cardiology recommends avoiding salt intake >6 g a day.3
References
- Yancy CW, Jessup M, Bozkurt B, et al. 2013 ACCF/AHA guideline for the management of heart failure: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol. Oct 15 2013;62(16):e147-239. doi:10.1016/j.jacc.2013.05.019
- Chobanian AV, Bakris GL, Black HR, et al. Seventh report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. Hypertension. Dec 2003;42(6):1206-52. doi:10.1161/01.HYP.0000107251.49515.c2
- Ponikowski P, Voors AA, Anker SD, et al. 2016 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure: The Task Force for the diagnosis and treatment of acute and chronic heart failure of the European Society of Cardiology (ESC)Developed with the special contribution of the Heart Failure Association (HFA) of the ESC. Eur Heart J. Jul 14 2016;37(27):2129-2200. doi:10.1093/eurheartj/ehw128
- 2015-2020 Dietary Guidelines | health.gov. https://health.gov/dietaryguidelines/2015/guidelines/
- Rifai L, Silver MA. A Review of the DASH Diet as an Optimal Dietary Plan for Symptomatic Heart Failure. Prog Cardiovasc Dis. Mar-Apr 2016;58(5):548-54. doi:10.1016/j.pcad.2015.11.001
- Abu-Sawwa R, Dunbar SB, Quyyumi AA, Sattler ELP. Nutrition intervention in heart failure: should consumption of the DASH eating pattern be recommended to improve outcomes? Heart Fail Rev. Jul 2019;24(4):565-573. doi:10.1007/s10741-019-09781-6
- Willett WC, Sacks F, Trichopoulou A, et al. Mediterranean diet pyramid: a cultural model for healthy eating. Am J Clin Nutr. Jun 1995;61(6 Suppl):1402s-1406s. doi:10.1093/ajcn/61.6.1402S
- Fung TT, Rexrode KM, Mantzoros CS, Manson JE, Willett WC, Hu FB. Mediterranean diet and incidence of and mortality from coronary heart disease and stroke in women. Circulation. Mar 3 2009;119(8):1093-100. doi:10.1161/circulationaha.108.816736
- Lopez-Garcia E, Rodriguez-Artalejo F, Li TY, et al. The Mediterranean-style dietary pattern and mortality among men and women with cardiovascular disease. Am J Clin Nutr. Jan 2014;99(1):172-80. doi:10.3945/ajcn.113.068106
- Estruch R, Ros E, Salas-Salvado J, et al. Primary Prevention of Cardiovascular Disease with a Mediterranean Diet Supplemented with Extra-Virgin Olive Oil or Nuts. N Engl J Med. Jun 21 2018;378(25):e34. doi:10.1056/NEJMoa1800389
- Papadaki A, Martinez-Gonzalez MA, Alonso-Gomez A, et al. Mediterranean diet and risk of heart failure: results from the PREDIMED randomized controlled trial. Eur J Heart Fail. Sep 2017;19(9):1179-1185. doi:10.1002/ejhf.750
- Mahtani KR, Heneghan C, Onakpoya I, et al. Reduced Salt Intake for Heart Failure: A Systematic Review. JAMA Intern Med. Dec 1 2018;178(12):1693-1700. doi:10.1001/jamainternmed.2018.4673
- Lennie TA, Song EK, Wu JR, et al. Three gram sodium intake is associated with longer event-free survival only in patients with advanced heart failure. J Card Fail. Apr 2011;17(4):325-30. doi:10.1016/j.cardfail.2010.11.008
- He J, Ogden LG, Bazzano LA, Vupputuri S, Loria C, Whelton PK. Dietary Sodium Intake and Incidence of Congestive Heart Failure in Overweight US Men and Women. Archives of Internal Medicine. 2002-07-22 2002;162(14):1619. doi:10.1001/archinte.162.14.1619
- Doukky R, Avery E, Mangla A, et al. Impact of Dietary Sodium Restriction on Heart Failure Outcomes. JACC Heart Fail. Jan 2016;4(1):24-35. doi:10.1016/j.jchf.2015.08.007