Blue Cross of Idaho Logo

Express Sign-on

Thank you for registering with Blue Cross of Idaho

If you are an Individual or Family Member under age 65, please register here.

If you are an Medicare or Medicare Supplement member, please register here.

New Options for Affordable Health Insurance


MP 8.01.02 Chelation Therapy

Medical Policy    
Original Policy Date
Last Review Status/Date
Reviewed with literature search/6:2013
  Return to Medical Policy Index


Our medical policies are designed for informational purposes only and are not an authorization, or an explanation of benefits, or a contract.  Receipt of benefits is subject to satisfaction of all terms and conditions of the coverage.  Medical technology is constantly changing, and we reserve the right to review and update our policies periodically. 


Chelation therapy, an established treatment for treating heavy metal toxicities, has been investigated for a variety of other applications including treatment of atherosclerosis, Alzheimer’s disease, and autism.


Chelation therapy is an established treatment for the removal of metal toxins by converting them to a chemically inert form that can be excreted in the urine. Chelation therapy consists of the intravenous or oral administration of chelating agents that remove metal ions such as lead, aluminum, mercury, arsenic, zinc, iron, copper, and calcium from the body.

Specific chelating agents are used for particular heavy metal toxicities. For example, desferroxamine is used for patients with iron toxicity, and calcium-ethylenediaminetetraacetic acid (-EDTA) is used for patients with lead poisoning. Note that disodium-EDTA is not recommended for acute lead poisoning due to the increased risk of death from hypocalcemia. (1) Another class of chelating agents, called metal protein attenuating compounds (MPACs), is under investigation for the treatment of Alzheimer’s disease, which is associated with the disequilibrium of cerebral metals. Unlike traditional systemic chelators that bind and remove metals from tissues systemically, MPACs have subtle effects on metal homeostasis and abnormal metal interactions. In animal models of Alzheimer’s disease, they promote the solubilization and clearance of Aβ-amyloid protein by binding its metal-ion complex and also inhibit redox reactions that generate neurotoxic free radicals. MPACs therefore interrupt two putative pathogenic processes of Alzheimer’s disease. However, no MPACs have received U.S. Food and Drug Administration (FDA) approval for the treatment of Alzheimer’s disease. Chelation therapy has also been discussed as a treatment for other indications including atherosclerosis and autism. For example, EDTA chelation therapy has been proposed in patients with atherosclerosis as a method of decreasing obstruction in the arteries.

Regulatory Status

Calcium-EDTA was approved by the FDA for lowering blood lead levels among patients with lead poisoning. Disodium-EDTA was approved by the FDA for use in selected patients with hypercalcemia and for use in patients with heart rhythm problems due to intoxication with the drug, digitalis. In 2008, the FDA withdrew approval of disodium-EDTA due to safety concerns and recommended that other forms of chelation therapy be used. (2)

Several iron chelating agents have received FDA approval. Deferoxamine for subcutaneous, intramuscular, or intravenous injections was approved for treating acute iron intoxication and chronic iron overload due to transfusion-dependent anemia. Deferasirox, approved in 2005, is available as a tablet for oral suspension and is indicated for the treatment of chronic iron overload due to blood transfusions in patients age 2 years and older. Under the accelerated approval program, the FDA expanded approval of deferasirox in 2013 to include the treatment of patients age 10 and older with chronic iron overload due to nontransfusion-dependent thalassemia (NTDT). In 2011, the FDA approved the iron chelator deferiprone for the treatment of patients with transfusional overload due to thalassemia syndromes when other chelation therapy is inadequate. Deferiprone is available in tablet form for oral use.


Chelation therapy may be considered medically necessary in the treatment of each of the following conditions:

  • control of ventricular arrhythmias or heart block associated with digitalis toxicity;
  • emergency treatment of hypercalcemia;
  • extreme conditions of metal toxicity;
  • treatment of chronic iron overload due to blood transfusions (transfusional hemosiderosis) and due to nontransfusion-dependent thalassemia (NDTD);
  • Wilson's disease (hepatolenticular degeneration); and
  • lead poisoning.

Other applications of chelation therapy are considered investigational, including, but not limited to:

  • atherosclerosis (.. e.g., coronary artery disease, secondary prevention in patients with myocardial infarction, or peripheral vascular disease);
  • multiple sclerosis;
  • arthritis (includes rheumatoid arthritis);
  • hypoglycemia;
  • autism;
  • Alzheimer’s disease; and
  • diabetes

Policy Guidelines



Benefit Application
BlueCard/National Account Issues

No applicable information 


The policy was created in 1995 with a search of the MEDLINE database. The policy was updated regularly with literature searches using MEDLINE, most recently the literature was searched from the period February 2012 through April 24, 2013.

Chelation therapy is an established treatment for the indications listed in the medically necessary policy statement, particularly for the treatment of metal toxicity and transfusional hemosiderosis. Thus, literature searches have focused on the use of chelation therapy for other conditions including, but not limited to, atherosclerosis, autism, Alzheimer’s disease, multiple sclerosis, and diabetes.


In 2002, a Cochrane review was published evaluating studies on ethylenediaminetetraacetic acid (EDTA) chelation therapy for treating patients with atherosclerotic cardiovascular disease. (3) Five placebo-controlled randomized-controlled trials (RCTs) were identified, none of which reported mortality, non-fatal events, and cerebrovascular vascular events. Four of the 5 studies (total n=250) found no significant benefits of EDTA chelation therapy on outcomes reported including direct or indirect measurement of disease severity and subjective measures of improvement. The fifth study, which included only 10 patients, was apparently stopped early due to benefit, but relevant outcome data were not available. The Cochrane reviewers concluded that there was insufficient evidence to draw conclusions of the efficacy of chelation therapy for treating atherosclerosis; additional RCTs that report health outcomes including mortality and cerebrovascular events were needed.

Among the published randomized controlled trials (RCTs), Knudtson and colleagues randomized 84 patients with coronary artery disease and a positive treadmill test to receive EDTA chelation therapy or placebo, 3 hours per treatment twice weekly for 15 weeks, and once per month for an additional 3 months. (4) The main outcome measures included change in time to ischemia, functional reserve for exercise, and quality of life. There was no significant difference between the two groups. Another double-blind, randomized controlled study of EDTA chelation or placebo showed no change in short- or long-term improvement in vasomotor response to EDTA when compared to placebo. (5) Two small randomized trials have also reported no benefit of chelation therapy as a treatment of peripheral arterial disease. (6, 7)

Section summary: Several RCTs have been published on chelation therapy for treating atherosclerosis; these have generally reported intermediate outcomes and have not found EDTA chelation therapy to be more effective than placebo. Additional RCTs that report health outcomes are needed to establish the efficacy of this treatment.


Based on similarities between mercury poisoning and autism spectrum disorder symptoms, Bernard and colleagues hypothesized a link between environmental mercury and autism. (8) This theory was rejected by Nelson and Bauman, who found that many of the characteristics of mercury poisoning such as ataxia, constricted visual fields, peripheral neuropathy, hypertension, skin eruption, and thrombocytopenia, are never seen in autistic children. (9) In 2007, a systematic review by Ng and colleagues concluded that there was no association between mercury poisoning and autism. (10)

In 2009, Rossignol published a systematic review of novel and emerging treatments for autism and did not identify any studies that included a control group. (11) The author stated the case series suggest that chelation might be a viable form of treatment in some autistic individuals with known elevated heavy metal levels and that this possibility needs to be further investigated in controlled studies.

Section summary: There is a lack of controlled studies on the effect of chelation therapy on health outcomes in patients with autism.

Alzheimer’s Disease

A 2008 Cochrane Review evaluated metal protein attenuating compounds (MPAC) for treating Alzheimer’s disease (12) The review identified one placebo-controlled RCT. This study, by Richie and colleagues, was published in 2003. Patients were treated with PBT1, an MPAC also known as clioquinol, an anti-fungal medication that crosses the blood-brain barrier. (13) Clioquinol was withdrawn for oral use in 1970 because of its association with subacute myelo-optic neuropathy. In the study, oral clioquinol was administered in doses increasing to 375 mg twice daily to 16 Alzheimer’s disease patients, and the effects were compared to 16 matched controls who received placebo. At 36 weeks, there was no statistically significant between-group difference in cognition measured by the Alzheimer’s Disease Assessment Scale – Cognitive (ADAS-Cog scale). One patient in the treatment group developed impaired visual acuity and color vision during weeks 31 to 36 while she was receiving clioquinol, 375 mg twice daily. Her symptoms resolved on treatment cessation.

Further studies of PBT1 have been abandoned in favor of a successor compound, PBT2. Lannfelt and colleagues completed a double-blind, placebo-controlled RCT in which 78 Alzheimer’s disease patients were treated for 12 weeks with 50 mg PBT2 (n=20), 250 mg PBT2 (n=29), or placebo (n=29). (14) There was no statistically significant difference in ADAS-Cog scale or Mini-Mental Status Exam scores among groups in this short-term study. The most common adverse event was headache. Two serious adverse events (urosepsis and transient ischemic event) were reported, both by patients receiving placebo.

Ongoing investigations in chelation therapy for the treatment of Alzheimer’s disease and other neurodegenerative diseases include linking a carbohydrate moiety to drug molecules to enhance drug delivery across the blood-brain barrier; this strategy may solve the potential problem of premature and indiscriminate metal binding. In addition, multi-function drugs that not only bind metal but also have significant antioxidant capacity are in development. (15)

Section summary: There is insufficient evidence on the safety and efficacy of chelation therapy for treating patients with Alzheimer’s disease. The few published RCTs did not find that the treatment was superior to placebo for improving health outcomes.


Cardiovascular disease in patients with diabetes

A 2009 trial by Cooper and colleagues in New Zealand evaluated the effect of copper chelation using oral trientine on left-ventricular hypertrophy in 30 patients with type 2 diabetes. (16) A total of 21/30 (70%) of the participants completed the 12-month follow-up. At 12 months, there was a significantly greater change in left ventricular mass indexed to body surface area (LVM) in the group receiving active treatment compared to placebo (-10.6 g/m2 vs. -0.1 g/m2, p=0.01). The study was limited by the small sample size and high drop-out rate.

Diabetic nephropathy

Chen and colleagues in China investigated the effect of chelation therapy on the progression of diabetic nephropathy in patients with high-normal lead levels. Their 2012 single-blind study included 50 patients with diabetes, high-normal body lead burden (80-6,000 ug) and serum creatinine 3.8 mg/dL or lower. (17) At baseline, the mean blood lead level was 6.3 ug/dL in the treatment group and 7.1 ug/dL in the control group and the mean body lead burden was 151 ug for patients in the treatment group and 142 ug for patients in the control group. According to the U.S. Occupational and Health Safety Administration (OSHA), the maximum acceptable blood lead level in adults is 40 ug/dL. (18) Patients were randomized to 3 months of calcium disodium EDTA or placebo. During the following 24 months, patients in the chelation group received additional chelation treatments as needed (i.e., if serum creatinine level exceeded pre-treatment levels or body lead burden was >60 ug) and patients in the placebo group continued to receive placebo medication. All patients completed the 27-month study. The primary outcome was change in estimated glomerular filtration rate (eGFR). The yearly rate of decrease in eGFR was 5.6 mL/min/173 m2 (standard deviation [SD]: 5.0) in the chelation group and 9.2 mL/min/173 m2 (SD: 3.6) in the control group. The difference between groups was statistically significant, p=0.04. The secondary endpoint was the number of patients in whom the baseline serum creatinine doubled or who required renal replacement therapy. A total of 9 patients (36%) in the treatment group and 17 (68%) in the control group attainted the secondary endpoint; the difference between groups was statistically significant (p=0.02). There were no reported side effects of chelation therapy during the 27-month study period.

Section summary: Two small RCTs with limitations represent insufficient evidence that chelation therapy is effective for treating cardiovascular disease in patients with diabetes. One small single-blind RCT is insufficient evidence that chelation therapy is effective for treating diabetic nephropathy in patients with high-normal lead levels. Additional RCTs with larger numbers of patients and that report health outcomes such as cardiovascular events, end-stage renal disease and mortality are needed.

Myocardial infarction (MI)

In 2013, findings of the randomized double-blind multicenter Trial to Assess Chelation Therapy (TACT) study were published. (19) The study included 1,708 individuals, age 50 or older, who had a history of a myocardial infarction at least 6 weeks previous and a serum creatinine level of 2.0 mg/dL or less. Patients were randomized to receive 40 infusions of disodium EDTA (n=839) or placebo (n=869). The first 30 infusions were given weekly, and the remaining 10 infusions were given 2 to 8 weeks apart. The primary endpoint was a composite outcome that included death from any cause, reinfarction, stroke, coronary revascularization or hospitalization for angina at 5 years. A total of 361 patients in the chelation group (43%) and 464 patients in the placebo group (57%) discontinued treatment after starting it, withdrew consent during follow-up or were lost to follow-up. The Kaplan-Meier 5-year estimates for the primary endpoint were 32.8% (95% confidence interval [CI]: 29.1% to 36.5%) in the chelation group and 38.5% (95% CI: 34.6% to 42.3%) in the control group. The difference between groups was statistically significant; the p value was 0.035, which was below the significance threshold required due to multiple (11) interim analyses, 0.036. The most common individual clinical endpoint was coronary revascularization, which occurred in 130 of 839 patients (15%) in the chelation group and 157 of 869 patients (18%) in the control group, p value=0.08. The next most frequent endpoint was death. This occurred in 87 of 839 (10%) of patients in the chelation group and 93 of 869 (11%) of patients in the placebo group, p value=0.64. None of the individual components of the primary outcome differed significantly between groups; however, the study was not powered to detect difference in individual components. Four severe adverse events occurred that were definitely or possibly related to study therapy. There were 2 events each in the treatment and control group, including 1 death in each group.

The study is limited by the low follow-up rate, including a greater number of patients who withdrew consent in the placebo group compared to the treatment group. The primary endpoint included components of varying clinical significance, with most of the difference between groups occurring for revascularization events. The primary endpoint barely met the significance threshold and if more patients had been retained in the study and experienced events, results could have differed. Moreover, as noted in an editorial accompanying the publication, 60% of patients were enrolled at centers described as complementary and alternative medicine sites, and this may have resulted in a population that is not generalizable to that seen in clinical care. (20)

Section summary: One RCT with limitations, including high dropout with differential drop-out between groups, reported that cardiovascular events are reduced in patients treated with chelation therapy. However, this was not a high-quality trial and therefore the results could have arisen from bias. Further trials that are of high quality are needed to corroborate whether chelation therapy improves outcomes in patients with prior MI.

Other potential indications

No RCTs or other controlled studies were identified that evaluated the safety and efficacy of chelation therapy for other conditions such as multiple sclerosis or arthritis.


Chelation therapy is an established treatment for the medically necessary indications listed in the policy statement, such as treatment of metal toxicity and transfusional hemosiderosis. There is insufficient evidence that chelation therapy improves health outcomes for patients with other conditions including, but not limited to, atherosclerosis, autism, Alzheimer’s disease, diabetes and arthritis. Thus, chelation therapy for these other applications is considered investigational.

Practice Guidelines and Position Statements

In 2012, the American College of Physicians, American College of Cardiology Foundation, American Heart Association, American Association for Thoracic Surgery, Preventive Cardiovascular Nurses Association and Society of Thoracic Surgeons published a clinical practice guideline on management of stable ischemic heart disease (IHD). (21) The organizations recommended that “chelation therapy should not be used with the intent of improving symptoms or reducing cardiovascular risk in patients with stable IHD. (Grade: strong recommendation; low-quality evidence)”

A 2004 clinical practice guideline from the American College of Physicians (22) states that chelation “should not be used to prevent myocardial infarction or death or to reduce symptoms in patients with symptomatic chronic stable angina. (Level of evidence B: Based on evidence from a limited number of randomized trials with small numbers of patients, careful analyses of nonrandomized studies, or observational registries.)”

In 2005, the American College of Cardiology (23) stated that chelation “is not indicated for treatment of intermittent claudication and may have harmful adverse effects. (Level of Evidence A: Data derived from multiple randomized clinical trials or meta-analyses.)”


  1. Centers for Disease Control and Prevention. Deaths associated with hypocalcemia from chelation therapy--Texas, Pennsylvania, and Oregon, 2003-2005. MMWR Morb Mortal Wkly Rep 2006; 55(8):204-7.
  2. Food and Drug Adminstration. Hospira, Inc., et al.; Withdrawal of Approval of One New Drug Application and Two Abbreviated New Drug Application. Available online at: Last accessed May, 2013.
  3. Villarruz MV, Dans A, Tan F. Chelation therapy for atherosclerotic cardiovascular disease. Cochrane Database Syst Rev 2002; (4):CD002785.
  4. Knudtson ML, Wyse DG, Galbraith PD et al. Chelation therapy for ischemic heart disease: a randomized controlled trial. JAMA 2002; 287(4):481-6.
  5. Anderson TJ, Hubacek J, Wyse DG et al. Effect of chelation therapy on endothelial function in patients with coronary artery disease: PATCH substudy. J Am Coll Cardiol 2003; 41(3):420-5.
  6. Guldager B, Jelnes R, Jorgensen SJ et al. EDTA treatment of intermittent claudication--a double-blind placebo-controlled study. J Intern Med 1992; 231(3):261-7.
  7. Van Rij A. M., Solomon C, Packer SG et al. Chelation therapy for intermittent claudication: A double-blind, randomized, controlled trial. Circulation 1994; 90(3):1194-9.
  8. Bernard S, Enayati A, Redwood L et al. Autism: a novel form of mercury poisoning. Med Hypotheses 2001; 56(4):462-71.
  9. Nelson KB, Bauman ML. Thimerosal and autism? Pediatrics 2003; 111(3):674-9.
  10. Ng DK, Chan CH, Soo MT et al. Low-level chronic mercury exposure in children and adolescents: meta-analysis. Pediatr Int 2007; 49(1):80-7.
  11. Rossignol DA. Novel and emerging treatments for autism spectrum disorders: A systematic review. Ann Clin Psychiatry 2009; 21(4-Jan):213-36.
  12. Sampson E, Jenagaratnam L, McShane R. Metal protein attenuating compounds for the treatment of Alzheimer’s disease. Cochrane Database Syst Rev 2008; (1):CD005380.
  13. Ritchie CW, Bush AI, Mackinnon A et al. Metal-protein attenuation with Iodochlorhydroxyquin (clioquinol) targeting Aß amyloid deposition and toxicity in Alzheimer disease: a pilot phase 2 clinical trial. Arch Neurol 2003; 60(12):1685-91.
  14. Lannfelt L, Blennow K, Zetterberg H et al. Safety, efficacy, and biomarker findings of PBT2 in targeting Abeta as a modifying therapy for Alzheimer's disease: a phase IIa, double-blind, randomised, placebo-controlled trial. Lancet Neurol 2008; 7(9):779-86.
  15. Cavalli A, Bolognesi ML, Minarini A et al. Multi-target-directed ligands to combat neurodegenerative diseases. J Med Chem 2008; 51(3):347-72.
  16. Cooper GJ, Young AA, Gamble GD et al. A copper(II)-selective chelator ameliorates left-ventricular hypertrophy in type 2 diabetic patients: a randomized placebo-controlled study. Diabetologia 2009; 52(4):715-22.
  17. Chen KH, Lin JL, Lin-Tan DT et al. Effect of chelation therapy on progressive diabetic nephropathy in patients with type 2 diabetes and high-normal body lead burdens. Am J Kidney Dis 2012; 60(4):530-8.
  18. U.S. Department of Labor Occupational Health and Safety Adminstration (OSHA). Safety and Health Regulations for Construction. Available online at: Last accessed May, 2013.
  19. Lamas GA, Goertz C, Boineau R et al. Effect of disodium EDTA chelation regimen on cardiovascular events in patients with previous myocardial infarction: the TACT randomized trial. JAMA 2013; 309(12):1241-50.
  20. Nissen SE. Concerns about reliability in the Trial to Assess Chelation Therapy (TACT). JAMA 2013; 309(12):1293-4.
  21. American College of Physicians/American College of Cardiology Foundation/American Heart Association/American Association for Thoracic Surgery/Preventive Cardiovascular Nurses Association/Society of Thoracic Surgeons. Management of stable ischemic heart disease. Available online at: Last accessed May, 2013.
  22. Snow V, Barry P, Fihn SD et al. Primary care management of chronic stable angina and asymptomatic suspected or known coronary artery disease: a clinical practice guideline from the American College of Physicians. Ann Intern Med 2004; 141(7):562-7.
  23. Hirsch AT, Haskal ZJ, Hertzer NR et al. ACC/AHA 2005 Practice Guidelines for the management of patients with peripheral arterial disease (lower extremity, renal, mesenteric, and abdominal aortic): a collaborative report from the American Association for Vascular Surgery/Society for Vascular Surgery, Society for Cardiovascular Angiography and Interventions, Society for Vascular Medicine and Biology, Society of Interventional Radiology, and the ACC/AHA Task Force on Practice Guidelines (Writing Committee to Develop Guidelines for the Management of Patients With Peripheral Arterial Disease): endorsed by the American Association of Cardiovascular and Pulmonary Rehabilitation; National Heart, Lung, and Blood Institute; Society for Vascular Nursing; TransAtlantic Inter-Society Consensus; and Vascular Disease Foundation. Circulation 2006; 113(11):e463-654.  




CPT  96365  Intravenous infusion, for therapy, prophylaxis, or diagnosis (specify substance or drug); initial, up to 1 hour  
  96366 each additional hour (list separately in addition to code for primary procedure) 
  96374 Therapeutic, prophylactic, or diagnostic injection (specify substance or drug); intravenous push, single or initial substance/drug 
ICD-9 Procedure  99.16  Injection of antidote (heavy metal antagonist) 
ICD-9 Diagnosis  275.1   
  275.4  Hypercalcemia 
  282.4  Thalassemia intermedia 
  427.9  Arrhythmia 
  984–984.9  Lead poisoning code range 
  440  Atherosclerosis (code range) 
  999.8, 999.89 Other infusion and trasnfusion reaction not elsewhere classified
HCPCS  M0300  IV chelation therapy (chemical endarterectomy) 
  J0470  Injection, dimercaprol, per 100 mg 
  J0600  Injection, edetate calcium disodium, up to 1000 mg 
  J3520  Edetate disodium, per 150 mg 
  S9355 Home infusion therapy, chelation therapy; administrative services, professional pharmacy services, care coordination, and all necessary supplies and equipment (drugs and nursing visits coded separately), per diem
ICD-10-CM (effective 10/1/14) D56.0-D56.9 Thalassemia code range
  E83.01 Wilson's disease
   E83.52 Hypercalcemia
   M10.1-M19 Lead induced gout code range
   T46.0x1A – T46.0x6S Poisoning by, adverse effect of and underdosing of cardiac-stimulant glycosides and drugs of similar action code range (7th character indicates initial encounter [A], subsequent encounter [D] or sequel [S])
   T56.0x1A – T56.94xS Toxic effects of metal code range (7th character indicates initial encounter [A], subsequent encounter [D] or sequel [S])
   T80.89 Other complications following infusion, transfusion and therapeutic injection (includes transfusionalhemosiderosis)
ICD-10-PCS (effective 10/1/14)    ICD-10-PCS codes are only used for inpatient services.
   3E030GC, 3E033GC Introduction, therapeutic substance, peripheral vein, code by approach (open or percutaneous)
   3E040GC, 3E043GC Introduction, therapeutic substance, central vein, code by approach (open or percutaneous)
   3E050GC, 3E053GC Introduction, therapeutic substance, peripheral artery, code by approach (open or percutaneous)
   3E060GC, 3E063GC Introduction, therapeutic substance, central artery, code by approach (open or percutaneous)
Type of Service  Injection 



Chelation therapy
Chemical endarterectomy

Policy History
Date Action Reason
12/1/95 Add to Surgery section New policy
07/12/02 Replace policy Policy reviewed; policy statement unchanged, rationale, references added
10/09/03 Replace policy Policy reviewed by consensus without literature review; no changes in policy; no further review scheduled
12/14/05 Replace policy – coding update only CPT coding updated
12/11/08 Replace policy  Policy returned to “active review” status. Policy updated with literature review; policy statements revised to indicate that chelation therapy may be considered medically necessary in the treatment of iron overload due to transfusional hemosiderosis and considered investigational in the treatment of autism and Alzheimer’s disease. Other policy statements are unchanged. Reference numbers 1-3,5, 10-13 added 
01/14/10 Replace policy Policy updated with literature review; references 14-23 added; policy statements unchanged. “Includes rheumatoid arthritis” was added to the investigational policy statement for arthritis.
4/14/11 Replace policy Policy updated with literature review; reference numbers 2 and 21 added; other references renumbered. No change to policy statements.
04/12/12 Replace policy Policy updated with literature review. Rationale re-written. References 16 and 17 added; other references renumbered or removed.
6/13/13 Replace policy Policy updated with literature review through April 24, 2013. References 17-21; other references renumbered or removed. Chronic iron overload due to nontransfusion-dependent thalassemia (NDTD) added to medically necessary statement based on new FDA approval. Secondary prevention in patients with myocardial infarction added to bullet point in investigational statement on atherosclerosis; in that bullet point, “i.e.” changed to “e.g.”