EAL

Omega-3 Fatty Acid Supplementation

Author and Year:

Nodari S, Trigging M et al, 2011

PubMed ID:

Article Title:

Effects of n-3 polyunsaturated fatty acids on left ventricular function and functional capacity in patients with dilated cardiomyopathy.

Authors:

Nodari S, Triggiani M, Campia U, Manerba A, Milesi G, Cesana B, Gheorghiade M, Dei Cas L

Journal:

Journal of the American College of Cardiology

Year of publication:

2011

Volume:

Issue:

Page numbers:

870-9

Study Design:

Randomized Controlled Trial

Risk of Bias Assessment Rating:

Positive

Inclusion Criteria:

Patients aged between 18 and 75 years with a diagnosis of NICM, LV systolic dysfunction (defined as an EF 45%) and stable clinical conditions with minimal or no symptoms for at least three months on evidence-based medical treatment at maximum tolerated target doses for at least six months were considered eligible for the study. In all patients, the diagnosis of NICM was based on the absence of stenoses 50% on coronary artery angiography performed at the time of the workup of the cardiomyopathy. Furthermore, additional imaging tests had been performed in the presence of subsequent changes in clinical status or if symptoms suggestive of ischemia had occurred.

Exclusion Criteria:

The following criteria were grounds for exclusion: Presence of symptoms or evidence of coronary artery disease diagnosed through non-invasive tests, peripheral arterial disease, presence of congenital or primary valvular heart disease, persistent atrial fibrillation, inability to perform bicycle ergometry for non-cardiac causes, moderately to severely reduced functional capacity, NYHA functional class IV, poor acoustic windows limiting the ability to assess echocardiographic measurements, chronic lung disease, advanced renal disease (estimated glomerular filtration rate [eGFR] 30ml per minute per 1.73m2), advanced liver disease; any disease limiting life expectancy to one year, contraindications to study drugs and concomitant participation in other research studies.

Research Purpose:

This study was designed to test the effects of N-3 polyunsaturated fatty acids (PUFAs) on left ventricular (LV) systolic function in chronic heart failure (HF) due to non-ischemic dilated cardiomyopathy (NICM).

Blinding efforts:

Echocardiographic exams were performed by a single cardiologist (GM) and interpreted by a different cardiologist (AM), both blinded to patients’ treatment. CPET exams were performed and interpreted by two cardiologists (AM and GM) blinded to patients’ treatment.

Study Location:

Italy

Source(s) of Funding:

Government

Please specify names of funders:

Study was funded by a grant from the "Centro per lo Studio ed il Trattamento dello Scompenso Cardiaco."

Quality Criteria Checklist: Primary Research
Relevance Questions
	1.	Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies)	Yes
	2.	Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about?	Yes
	3.	Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice?	Yes
	4.	Is the intervention or procedure feasible? (NA for some epidemiological studies)	Yes

Validity Questions
1.	Was the research question clearly stated?		Yes
	1.1.	Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified?	Yes
	1.2.	Was (were) the outcome(s) [dependent variable(s)] clearly indicated?	Yes
	1.3.	Were the target population and setting specified?	Yes
2.	Was the selection of study subjects/patients free from bias?		Yes
	2.1.	Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study?	Yes
	2.2.	Were criteria applied equally to all study groups?	Yes
	2.3.	Were health, demographics, and other characteristics of subjects described?	Yes
	2.4.	Were the subjects/patients a representative sample of the relevant population?	Yes
3.	Were study groups comparable?		Yes
	3.1.	Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT)	Yes
	3.2.	Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline?	Yes
	3.3.	Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.)	Yes
4.	Was method of handling withdrawals described?		Yes
	4.1.	Were follow-up methods described and the same for all groups?	Yes
	4.2.	Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.)	N/A
	4.3.	Were all enrolled subjects/patients (in the original sample) accounted for?	Yes
	4.4.	Were reasons for withdrawals similar across groups?	N/A
5.	Was blinding used to prevent introduction of bias?		Yes
	5.1.	In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate?	Yes
	5.2.	Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.)	Yes
6.	Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described?		Yes
	6.1.	In RCT or other intervention trial, were protocols described for all regimens studied?	Yes
	6.3.	Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect?	Yes
	6.4.	Was the amount of exposure and, if relevant, subject/patient compliance measured?	Yes
	6.5.	Were co-interventions (e.g., ancillary treatments, other therapies) described?	Yes
	6.6.	Were extra or unplanned treatments described?	No
	6.7.	Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups?	Yes
7.	Were outcomes clearly defined and the measurements valid and reliable?		Yes
	7.1.	Were primary and secondary endpoints described and relevant to the question?	Yes
	7.2.	Were nutrition measures appropriate to question and outcomes of concern?	Yes
	7.3.	Was the period of follow-up long enough for important outcome(s) to occur?	Yes
	7.4.	Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures?	Yes
	7.5.	Was the measurement of effect at an appropriate level of precision?	Yes
	7.6.	Were other factors accounted for (measured) that could affect outcomes?	Yes
	7.7.	Were the measurements conducted consistently across groups?	Yes
8.	Was the statistical analysis appropriate for the study design and type of outcome indicators?		Yes
	8.1.	Were statistical analyses adequately described and the results reported appropriately?	Yes
	8.2.	Were correct statistical tests used and assumptions of test not violated?	???
	8.3.	Were statistics reported with levels of significance and/or confidence intervals?	Yes
	8.4.	Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)?	Yes
	8.5.	Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)?	Yes
	8.6.	Was clinical significance as well as statistical significance reported?	No
	8.7.	If negative findings, was a power calculation reported to address type 2 error?	No
9.	Are conclusions supported by results with biases and limitations taken into consideration?		Yes
	9.1.	Is there a discussion of findings?	Yes
	9.2.	Are biases and study limitations identified and discussed?	Yes
10.	Is bias due to study's funding or sponsorship unlikely?		Yes
	10.1.	Were sources of funding and investigators' affiliations described?	Yes
	10.2.	Was the study free from apparent conflict of interest?	Yes