Theisen-Toupal J, Horowitz G, Breu A. Low Yield of Outpatient Serum Folate TestingEleven Years of Experience. JAMA Intern Med. 2014;174(10):1696-1697. doi:10.1001/jamainternmed.2014.3593
Since the United States began folic acid fortification in 1998, the prevalence of folate deficiency in the general population has decreased.1 Despite this, folate testing continues to be recommended for the evaluation of macrocytic anemia2,3 and is commonly performed to evaluate macrocytosis without anemia, normocytic anemia, dementia, delirium, and peripheral neuropathy.4- 6 We aimed to determine the utility of serum folate testing in an outpatient population.
We conducted a retrospective review of all outpatient serum folate tests performed at a large academic medical center in Boston, Massachusetts, from January 1, 2003, through December 31, 2013. The study was reviewed by the Beth Israel Deaconess Medical Center Institutional Review Board and was determined to be exempt. No informed consent was required because this study was retrospective and observational (and thus did not affect patient care in any way). Serum folate values were determined using a chemiluminescent competitive binding protein assay on an E170 analyzer as prescribed by the manufacturer (Roche Diagnostics Corporation). Serum folate levels were defined as deficient (<3.0 ng/mL; to convert to nanomoles per liter, multiply by 2.266), low-normal (3.0-3.9 ng/mL), normal (4.0-19.9 ng/mL), or high (>19.9 ng/mL).4,6 To determine whether changes in the number of serum folate tests ordered were specific to folate or were reflective of a general trend in overall ordering of laboratory tests, we compared the number of serum folate tests performed with the number of serum creatinine tests performed as a function of time. In addition, we performed cost, reimbursement, and charge analyses of serum folate testing based on 2014 institutional cost and charge figures (<$2.00 per test and $128.00 per test, respectively) and the 2014 Massachusetts Medicare fee schedule figure ($20.02 per test). Descriptive statistics were used to analyze the data.
From January 1, 2003, through December 31, 2013, a total of 84 187 serum folate levels were measured in 77 627 individuals. There were 47 deficient (0.056%), 166 low-normal (0.197%), 57 411 normal (68.195%), and 26 563 high (31.552%) levels (Table 1). The mean (SE) slope of folate to creatinine by year was −0.000474 (0.000305), with t9= −1.554 and P = .15, which indicates that year does not have a significant effect on the ratio of serum folate to serum creatinine levels performed. Cost, charge, and reimbursement analyses are given in Table 2.
In this retrospective review, we determined the rate of serum folate deficiency to be exceedingly low in the outpatient population because only 0.056% of serum folate levels measured were in the deficient range. This finding likely represents the significant reduction in folate deficiency since folic acid fortification began in 1998, in addition to an extreme overuse of serum folate testing. Despite the low rate of serum folate deficiency, there has been no change in ordering habits relative to routinely ordered tests, such as creatinine. We also performed cost, charge, and reimbursement analyses. From January 1, 2003, through December 31, 2013, the overall costs, charges, and reimbursements were $168 374, $10 775 936, and $1 685 424, respectively. This amount represents a net surplus of $1 517 050 ($137 913 per year) for the medical center.
The low rate of deficiency, high rate of overuse, and favorable payment status of serum folate testing present an interesting financial dilemma to the medical center. Every physician and medical center should aim to provide high-value care. In the case of serum folate, this would mean a significant reduction, or perhaps elimination, of testing, which in fee-for-service payment models would result in a significant loss in revenue to the medical center. The weakness of this report is that it is a retrospective study from a single institution. The results may not be generalizable to other institutions or populations.
In summary, serum folate testing is overused and deficiency is rare in the outpatient setting. Although this test generates revenue for medical centers, the goal of providing high-value patient care suggests that serum folate testing should be significantly reduced or even eliminated in the outpatient setting.
Accepted for Publication: June 4, 2014.
Corresponding Author: Jesse Theisen-Toupal, MD, Beth Israel Deaconess Medical Center, 330 Brookline Ave, Span 2, Boston, MA 02215 (firstname.lastname@example.org).
Published Online: August 11, 2014. doi:10.1001/jamainternmed.2014.3593.
Author Contributions: Drs Theisen-Toupal and Horowitz had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: Theisen-Toupal, Breu.
Acquisition, analysis, or interpretation of data: All authors.
Drafting of the manuscript: Theisen-Toupal.
Critical revision of the manuscript for important intellectual content: All authors.
Statistical analysis: Theisen-Toupal, Horowitz.
Study supervision: Breu.
Conflict of Interest Disclosures: None reported.