EAL

DLM: Homocysteine, Folate, B-12 (2001)

Citation:

Study Design:

Class:

- Click here for explanation of classification scheme.

Quality Rating:

Research Purpose:

To summarize "the non-hematologic manifestations of folate deficiency (neural tube defects, cardiovascular disease, colon cancer) and their implications for clinical practice"
Dietary sources of folate are provided as well as suggested focus areas for future research.

Inclusion Criteria:

None described.

Exclusion Criteria:

None described.

Description of Study Protocol:

The authors provide a review of "seminal studies in the clinical applications of folate metabolism."

Data Collection Summary:

Study selection criteria were not described.

Description of Actual Data Sample:

The authors list five seminal studies related to folate research and have a total of 19 references encompassing the relationship between folate and neural tube defects, cardiovascular disease and colon cancer.

Summary of Results:

Neural tube defects: Four controlled intervention trials demonstrated that higher intakes of folate during the first six weeks of pregnancy could lower the incidence of birth defects by ~80%; mechanism unknown
Cardiovascular disease: Blood homocysteine levels can be decreased by increased intake of folate. However, it has not been demonstrated that decreasing homocysteine levels will result in a decreased incidence of cardiovascular events.
Colon cancer: More than15 epidemiologic studies indicate an inverse relationship between the risk of colorectal neoplasia and dietary intakes of folate; mechanism unknown
Sources of folate: Fortified cereals, lentils, chickpeas, black beans, beef liber, spinach, asparagus

Author Conclusion:

Folate has transformed itself from a vitamin formerly thought of just interms of prevention of anemia into a compound that has major implication as in regard to some of the most important public health problems (i.e., congenital birth defects, cardiovascular disease and cancer).

Funding Source:

University/Hospital:

Tuffs University

Reviewer Comments:

Methods of study selection are not described
No indicators of precision of findings is provided.

Quality Criteria Checklist: Review Articles
Relevance Questions
	1.	Will the answer if true, have a direct bearing on the health of patients?	Yes
	2.	Is the outcome or topic something that patients/clients/population groups would care about?	Yes
	3.	Is the problem addressed in the review one that is relevant to dietetics practice?	Yes
	4.	Will the information, if true, require a change in practice?	Yes

Validity Questions
	1.	Was the question for the review clearly focused and appropriate?	No
	2.	Was the search strategy used to locate relevant studies comprehensive? Were the databases searched and the search termsused described?	No
	3.	Were explicit methods used to select studies to include in the review? Were inclusion/exclusion criteria specified andappropriate? Wereselectionmethods unbiased?	No
	4.	Was there an appraisal of the quality and validity of studies included in the review? Were appraisal methodsspecified,appropriate, andreproducible?	No
	5.	Were specific treatments/interventions/exposures described? Were treatments similar enough to be combined?	No
	6.	Was the outcome of interest clearly indicated? Were other potential harms and benefits considered?	Yes
	7.	Were processes for data abstraction, synthesis, and analysis described? Were they applied consistently acrossstudies and groups? Was thereappropriate use of qualitative and/or quantitative synthesis? Was variation in findings among studies analyzed? Were heterogeneity issued considered? If data from studies were aggregated for meta-analysis, was the procedure described?	No
	8.	Are the results clearly presented in narrative and/or quantitative terms? If summary statistics are used, are levels ofsignificance and/or confidence intervals included?	No
	9.	Are conclusions supported by results with biases and limitations taken into consideration? Are limitations ofthe review identified anddiscussed?	No
	10.	Was bias due to the review's funding or sponsorship unlikely?	???