Ratings for the strength of the recommendations (Strong, Fair, Weak, Consensus, Insufficient Evidence), conclusion grades (I-V), and statement labels (Conditional versus Imperative) are defined at the end of the "Major Recommendations" field.
Heart Failure (HF) Medical Nutrition Therapy and Heart Failure
HF: Medical Nutrition Therapy (MNT) and Heart Failure
Referral to a registered dietitian for MNT is recommended whenever an individual has heart failure. A planned initial visit lasting at least 45 minutes and at least one to three planned follow-up visits (at least 30 minutes each) can lead to improved dietary pattern and quality of life and decreases in edema and fatigue. Along with optimal pharmacological management, MNT may also reduce hospitalizations.
Strong, Imperative
Recommendation Strength Rationale
- Conclusion statement was Grade II
Heart Failure (HF) Protein Needs in Heart Failure Patients
HF: Protein Needs
In assessing protein needs for patients with HF, clinically stable depleted patients should have a daily intake of at least 1.37 g protein/kg and normally nourished patients should have a daily intake 1.12 g protein/kg in order to preserve their actual body composition or limit the effects of hypercatabolism. Research indicates that HF patients have significantly higher protein needs than those without HF, as measured by negative nitrogen balance.
Fair, Imperative
Recommendation Strength Rationale
- Conclusion statement was Grade III
Heart Failure (HF) Energy Needs in Heart Failure Patients
In assessing energy needs for patients with HF, the majority of studies indicate that use of indirect calorimetry best determines energy needs. When indirect calorimetry is not possible consider starting with usual predictive equations and adjusting for increased catabolic state.
Fair, Imperative
Recommendation Strength Rationale
- Conclusion statement was Grade III
Heart Failure (HF) Sodium and Fluid Restriction and Heart Failure
Fluid Intake
For patients with HF, fluid intake should be between 1.4 and 1.9 L (48 to 64 oz.) per day, depending on clinical symptoms (i.e., edema, fatigue, shortness of breath). Fluid restriction will improve clinical symptoms and quality of life.
Fair, Imperative
Sodium Intake
For patients with HF, sodium intake should be less than 2000 mg (2 g) per day. Sodium restriction will improve clinical symptoms (i.e., edema, fatigue) and quality of life.
Fair, Imperative
Recommendation Strength Rationale
- Conclusion statement was Grade II
Heart Failure (HF) Folate, B12, and Heart Failure
HF: Folate and Heart Failure
The practitioner should encourage patients with HF to consume at least the daily reference intake (DRI) for folate through food and/or a combination of B6, B12, and folate supplementation. Folate supplementation given with other vitamins/minerals has been shown to have beneficial clinical HF outcomes.
Fair, Imperative
HF: B12 and Heart Failure
A multi-vitamin/mineral containing B12 or a combination of B6, B12 and folate could be recommended in HF patients. This level of B12 supplementation (200 to 500 micrograms daily), given with other vitamins/minerals, has been shown to have beneficial clinical HF outcomes.
Fair, Imperative
Recommendation Strength Rationale
- Conclusion statement was Grade II
Heart Failure (HF) Thiamine Supplementation and Heart Failure
HF: Thiamine Supplementation
Since diuretic use can lead to thiamine deficiency in patients with HF, the practitioner should evaluate thiamine status. The practitioner should encourage the patient to consume at least the DRI through food and/or supplements. The practitioner should stay alert to future research involving thiamine.
Fair, Conditional
Recommendation Strength Rationale
- Conclusion statement was Grade III
Heart Failure (HF) Magnesium Supplementation and Heart Failure
The practitioner should encourage patients with HF to consume at least the DRI for magnesium through food and/or supplements. Low levels of magnesium may be present in patients with HF and irregular heart rhythms may occur. The practitioner should stay alert to future research involving magnesium.
Fair, Conditional
Recommendation Strength Rationale
- Conclusion statement was Grade II
Heart Failure (HF) Alcohol and Heart Failure
HF: Alcohol and Heart Failure
Current limited evidence does not justify encouraging those who do not drink alcohol to start doing so. If a patient currently drinks alcohol, and if not contraindicated, then a maximum of one drink per day for women and up to two drinks per day for men may be tolerated. This level of alcohol consumption has been demonstrated to not be harmful in HF patients.
Fair, Conditional
Recommendation Strength Rationale
- Conclusion statement was Grade II
Heart Failure (HF) L-Arginine, Carnitine, Coenzyme Q10, and Hawthorn
HF: L-Arginine, Carnitine, Coenzyme Q10, and Hawthorn
If a patient inquires about or is currently taking L-arginine, carnitine, coenzyme Q10 or hawthorn supplements, then the practitioner may discuss the limited evidence available regarding clinical HF outcomes. Research is inconclusive. The practitioner should stay alert to future research involving these supplements.
Weak, Conditional
Recommendation Strength Rationale
- Conclusion statements were Grades II and III
Definitions:
Conditional versus Imperative Recommendations
Recommendations can be worded as conditional or imperative statements. Conditional statements clearly define a specific situation, while imperative statements are broadly applicable to the target population without restraints on their pertinence. More specifically, a conditional recommendation can be stated in if/then terminology (e.g., If an individual does not eat food sources of omega-3 fatty acids, then 1g of EPA and DHA omega-3 fatty acid supplements may be recommended for secondary prevention).
In contrast, imperative recommendations "require," or "must," or "should achieve certain goals," but do not contain conditional text that would limit their applicability to specified circumstances. (e.g., Portion control should be included as part of a comprehensive weight management program. Portion control at meals and snacks results in reduced energy intake and weight loss).
Levels of Evidence
| Strength of Evidence Elements |
Grade I
Good/Strong
|
Grade II
Fair
|
Grade III
Limited/Weak
|
Grade IV
Expert Opinion Only
|
Grade V
Grade Not Assignable
|
Quality
- Scientific rigor/validity
- Considers design and execution
|
Studies of strong design for question
Free from design flaws, bias and execution problems
|
Studies of strong design for question with minor methodological concerns
OR
Only studies of weaker study design for question
|
Studies of weak design for answering the question
OR
Inconclusive findings due to design flaws, bias or execution problems
|
No studies available
Conclusion based on usual practice, expert consensus, clinical experience, opinion, or extrapolation from basic research
|
No evidence that pertains to question being addressed |
Consistency
Of findings across studies
|
Findings generally consistent in direction and size of effect or degree of association, and statistical significance with minor exceptions at most |
Inconsistency among results of studies with strong design
OR
Consistency with minor exceptions across studies of weaker designs
|
Unexplained inconsistency among results from different studies
OR
Single study unconfirmed by other studies
|
Conclusion supported solely by statements of informed nutrition or medical commentators |
NA |
Quantity
- Number of studies
- Number of subjects in studies
|
One to several good quality studies
Large number of subjects studies
Studies with negative results having sufficiently large sample size for adequate statistical power
|
Several studies by independent investigators
Doubts about adequacy of sample size to avoid Type I and Type II error
|
Limited number of studies
Low number of subjects studies and/or inadequate sample size within studies
|
Unsubstantiated by published studies |
Relevant studies have not been done |
Clinical Impact
- Importance of studies outcomes
- Magnitude of effect
|
Studied outcome relates directly to the question
Size of effect is clinically meaningful
Significant (statistical) difference is large
|
Some doubt about the statistical or clinical significance of effect |
Studies outcome is an intermediate outcome or surrogate for the true outcome of interest
OR
Size of effect is small or lacks statistical and/or clinical significance
|
Objective data unavailable |
Indicates area for future research |
Generalizability
To population of interest
|
Studied population, intervention and outcomes are free from serious doubts about generalizability |
Minor doubts about generalizability |
Serious doubts about generalizability due to narrow or different study population, intervention or outcomes studied |
Generalizability limited to scope of experience |
NA |
This grading system was based on the grading system from: Greer N, Mosser G, Logan G, Wagstrom Halaas G. A practical approach to evidence grading. Jt Comm. J Qual Improv. 2000; 26:700-712. In September 2004, The ADA Research Committee modified the grading system to this current version.
Criteria for Recommendation Rating
| Statement Rating |
Definition |
Implication for Practice |
| Strong |
A Strong recommendation means that the workgroup believes that the benefits of the recommended approach clearly exceed the harms (or that the harms clearly exceed the benefits in the case of a strong negative recommendation), and that the quality of the supporting evidence is excellent/good (grade I or II)*. In some clearly identified circumstances, strong recommendations may be made based on lesser evidence when high-quality evidence is impossible to obtain and the anticipated benefits strongly outweigh the harms. |
Practitioners should follow a Strong recommendation unless a clear and compelling rationale for an alternative approach is present. |
| Fair |
A Fair recommendation means that the workgroup believes that the benefits exceed the harms (or that the harms clearly exceed the benefits in the case of a negative recommendation), but the quality of evidence is not as strong (grade II or III)*. In some clearly identified circumstances, recommendations may be made based on lesser evidence when high-quality evidence is impossible to obtain and the anticipated benefits outweigh the harms. |
Practitioners should generally follow a Fair recommendation but remain alert to new information and be sensitive to patient preferences. |
| Weak |
A Weak recommendation means that the quality of evidence that exists is suspect or that well-done studies (grade I, II, or III)* show little clear advantage to one approach versus another. |
Practitioners should be cautious in deciding whether to follow a recommendation classified as Weak, and should exercise judgment and be alert to emerging publications that report evidence. Patient preference should have a substantial influencing role. |
| Consensus |
A Consensus recommendation means that Expert opinion (grade IV)* supports the guideline recommendation even though the available scientific evidence did not present consistent results, or controlled trials were lacking. |
Practitioners should be flexible in deciding whether to follow a recommendation classified Consensus, although they may set boundaries on alternatives. Patient preference should have a substantial influencing role. |
| Insufficient Evidence |
An Insufficient Evidence recommendation means that there is both a lack of pertinent evidence (grade V)* and/or an unclear balance between benefits and harms. |
Practitioners should feel little constraint in deciding whether to follow a recommendation labeled as Insufficient Evidence and should exercise judgment and be alert to emerging publications that report evidence that clarifies the balance of benefit versus harm. Patient preference should have a substantial influencing role. |
*Conclusion statements are assigned a grade based on the strength of the evidence. Grade I is good; grade II, fair; grade III, limited; grade IV signifies expert opinion only and grade V indicates that a grade is not assignable because there is no evidence to support or refute the conclusion. The evidence and these grades are considered when assigning a rating (Strong, Fair, Weak, Consensus, Insufficient Evidence - see chart above) to a recommendation.
Adapted by the American Dietetic Association from the American Academy of Pediatrics, Classifying Recommendations for Clinical Practice Guideline, Pediatrics. 2004;114;874-877.
