Sunday, November 22, 2009

Management of Vitamin D Deficiency Reviewed

From Medscape Medical News CME

News Author: Laurie Barclay, MD
CME Author: Laurie Barclay, MD

November 9, 2009 — Best practices for recognition, prevention, and management of vitamin D deficiency in the family practice setting are reviewed in the October 15 issue of American Family Physician. Vitamin D is essential for optimal skeletal development, maintenance of bone health, and neuromuscular function. In addition, vitamin D may play important roles in guarding against cardiovascular disease, depression, and colon cancer.

"In the 19th century, vitamin D deficiency was identified as the cause of the rickets epidemic in children living in industrialized cities," write Paula Bordelon, DO; Maria V. Ghetu, MD; and Robert Langan, MD, from St. Luke's Family Medicine Residency Program in Bethlehem, Pennsylvania. "This discovery led to the fortification of various foods, and the resolution of a major health problem associated with vitamin D deficiency. However, recent studies have shown that vitamin D deficiency and insufficiency are associated with other pathologic conditions in persons of all ages."

The diagnosis of vitamin D deficiency is often missed and the condition untreated because the signs and symptoms develop slowly or are nonspecific. These may include symmetric low back pain in women; proximal muscle weakness; muscle aches; and throbbing bone pain in the low back, pelvis, or lower extremities, or when pressure is applied to the sternum or tibia. Vitamin D deficiency may also be recognized in patients who have increased risk for falls and impaired physical function.

Risk factors for vitamin D deficiency include age older than 65 years, exclusive breast-feeding without vitamin D supplementation; dark skin; insufficient exposure to sunlight; sedentary lifestyle; and obesity, defined as body mass index greater than 30 kg/m2. In addition, use of anticonvulsants, glucocorticoids, or other medications that affect vitamin D metabolism may give rise to deficiency.

Diagnosis of suspected vitamin D deficiency is confirmed with a 25-hydroxyvitamin D level of less than 20 ng/mL (50 nmol/L). Vitamin D insufficiency is defined as a serum 25-hydroxyvitamin D level of 20 to 30 ng/mL (50 - 75 nmol/L).

Supplementation Recommendations

The American Academy of Pediatrics recommends that infants and children have vitamin D intake of at least 400 IU/day from diet and supplements to prevent vitamin D deficiency.

Supplementation of 400 IU/day is recommended for all breast-fed infants until they are ingesting at least 1 L/day (33.8 fl oz) of vitamin D–fortified formula or milk and for all infants who are not breast-fed but who are consuming less than 1 L/day of vitamin D–fortified formula or milk.

In addition, supplementation of 400 IU/day is recommended for all children and adolescents who do not get regular sunlight exposure, who do not consume at least 1 L/day of vitamin D–fortified formula or milk, or who do not take a daily multivitamin supplement containing at least 400 IU of vitamin D.

Studies in adults suggest that vitamin D supplementation of at least 700 to 800 IU per day is associated with lower rates of falls and fractures. Contraindications to vitamin D supplementation include tuberculosis or other granulomatous diseases, metastatic bone disease, sarcoidosis, or Williams syndrome.

When vitamin D deficiency or insufficiency is present, the goal of treatment is to normalize vitamin D levels to alleviate symptoms and lessen the risk for fractures, falls, and other adverse health outcomes. Oral ergocalciferol (vitamin D2), 50,000 IU per week for 8 weeks, may be effective treatment in patients with vitamin D deficiency.

Serum 25-hydroxyvitamin D levels should be checked when this 8-week course is completed, and if values have not reached or exceeded the minimal level, the patient should receive a second 8-week course of ergocalciferol.

"The optimal time for rechecking the serum levels after repletion has not been clearly defined, but the goal is to achieve a minimum level of 30 ng per mL," the review authors write. "If the serum 25-hydroxyvitamin D levels still have not risen, the most likely cause is nonadherence to therapy or malabsorption. If malabsorption is suspected, consultation with a gastroenterologist should be considered."

Once vitamin D levels normalize in patients who were deficient, they should receive maintenance dosages of cholecalciferol (vitamin D3), 800 to 1000 IU per day from dietary sources and/or supplements.

Because vitamin D is fat soluble and can be stored in fat, there are concerns regarding toxicity from excessive supplementation. Signs and symptoms of vitamin D toxicity may include headache, metallic taste, nephrocalcinosis or vascular calcinosis, pancreatitis, nausea, and/or vomiting.

Clinical Recommendations

Key clinical recommendations for practice, and their accompanying level of evidence rating, are as follows:

In older adults, vitamin D supplementation of 700 to 800 IU per day is associated with a lower risk for falls (level of evidence, B).
In older adults, vitamin D supplementation of 700 to 800 IU per day is associated with a lower risk for fractures (level of evidence, A).
To prevent vitamin D deficiency, infants and children with inadequate sun exposure should have vitamin D intake of 400 IU/day (level of evidence, C).
To prevent vitamin D deficiency, adults with inadequate sun exposure should have vitamin D intake of 400 to 600 IU per day (level of evidence, C).
Adults with vitamin D deficiency, except for those with malabsorption syndromes, should receive maintenance dosages of 800 to 1000 IU of vitamin D per day (level of evidence, C).
The review authors have disclosed no relevant financial relationships.

Am Fam Physician. 2009;80:841-846. Abstract

Severe Asthma Attacks in Kids Averted by Fluticasone/salmeterol Combo

From Reuters Health Information

NEW YORK (Reuters Health) Nov 11 - In asthmatic children, treatment with fluticasone plus salmeterol is associated with fewer serious exacerbations and lower medical costs compared to the use of an inhaled corticosteroid (ICS) plus montelukast.

That's according to a retrospective study of insurance claims data presented by Dr. Richard Stanford, from GlaxoSmithKline in Research Triangle Park, North Carolina, at the annual scientific meeting of the American College of Allergy, Asthma and Immunology in Miami Beach, Florida.

Clinical trials in adults have shown that combining ICS with a long-acting beta-agonist such as salmeterol produces greater lung function improvements than combining the ICS with the leukotriene antagonist montelukast, Dr. Stanford told Reuters Health.

He added, "NIH asthma treatment guidelines recommend ICS plus a long-acting beta-agonist as one of two preferred therapies for children 4 to 11 years of age requiring medications greater than ICS monotherapy; the other preferred therapy is doubling the dose of ICS. ICS plus montelukast is an alternative therapy."

Using data from 2000 to 2008, Dr. Stanford and his colleagues identified 747 pairs of children, ages 4 to 11, on the two drug regimens. Pairs were matched in pre-index-date oral and inhaled corticosteroid use and respiratory-related hospitalizations and emergency department visits.

Results showed that, per 100 person-years, patients who started fluticasone/salmeterol had a significantly lower rate of asthma-related hospital inpatient visits (0.29 vs 33.91, adjusted hazard ratio 0.039) compared with the ICS/montelukast group. The corresponding rates of asthma-related emergency department plus inpatient events were 13.02 vs 56.84 (adjusted HR 0.44; p < 0.02 for both).

Average monthly costs for asthma treatment were $151 less in the fluticasone/salmeterol group than in the ICS/montelukast group.

"These data showed that fluticasone/salmeterol combination was associated with lower asthma-related serious exacerbations compared to ICS/montelukast in patients 4 to 11 years of age in a managed care setting," Dr. Stanford concluded.

GlaxoSmithKline markets the combination of fluticasone/salmeterol internationally under several trade names, including Advair in the United States.

No Adverse Events Reported So Far With H1N1 Influenza Vaccine

From Medscape Medical News

Fran Lowry

November 19, 2009 — No adverse events have been reported as yet from the H1N1 influenza vaccine, according to experts who are tracking the vaccine's safety through several postmarketing surveillance programs.

"So far we have no signals of concern in H1N1 vaccines nationally or internationally," Hector Izurieta, MD, MPH, from the US Food and Drug Administration Center for Biologics Evaluation and Research in Rockville, Maryland, told members of the FDA's Vaccines and Related Biological Products Advisory Committee yesterday.

Dr. Izurieta said concerns about the H1N1 vaccine's safety have prompted several passive and real-time safety surveillance enhancements to be put in place. This has resulted in stronger collaboration and communication among government agencies in the United States and worldwide, including Centers for Medicare & Medicaid Services, the Veterans Administration, Indian Health Services, and the World Health Organization.

Claudia Vellozzi, MD, MPH, from the Centers for Disease Control and Prevention (CDC)'s epidemiology and surveillance division in Atlanta, Georgia, reported that a total of 327,093 doses of H1N1 vaccine have been administered, according to CDC records, but that no potential association with signals have been identified.

No Signals, but Data Insufficient to Assess Safety

However, she added, "The 2009 H1N1 influenza vaccines have only recently begun to be administered, and the data are insufficient to assess safety of the vaccine to date, but there have been no signals."

Similar safety results are being seen with more than 2 million doses of seasonal influenza vaccine.

The US Department of Defense (DOD) has put into place 3 surveillance programs, said LTC Patrick Garman, PharmD, PhD, deputy director for scientific affairs, Military Vaccine Agency, Bethesda, Maryland.

These include enhanced surveillance of H1N1 vaccine safety in real time, or as close to real time as possible, among approximately 1.5 million military personnel who will be vaccinated during the 2009 to 2010 vaccination period.

"We just started this program November 2. We run through our database on Mondays, do the analysis, share the information with the vaccine safety data link with people at the CDC, they do a review, and we get the results back on Tuesday with statistical information attached," Dr. Garman explained to the committee.

A second program will compare International Statistical Classification of Diseases and Related Health Problems, Ninth Edition, codes to check for any unanticipated adverse effects that might not have been thought of earlier, he said.

The DOD is also monitoring the safety effects of the H1N1 vaccine in pregnancy.

So far, "at 2 weeks and counting," more than 30,000 vaccinations have been administered to military personnel throughout the world, including Iraq, Afghanistan, South Korea, Europe, Kosovo, and Japan, and more than 500,000 doses have been distributed within the DOD.
No high-priority outcomes such as Guillain-Barré syndrome have been identified.

The H1N1 vaccine is also being administered to DOD beneficiaries and to civilians who work for the DOD.

"I think we will end up vaccinating up to 3 million individuals in this program," Dr. Garman said. "So far, there have been no cases of adverse events to review, but the initial military vaccinees have not reached the end of their risk window."

Health Plans to Help With Surveillance

A novel H1N1 surveillance program is enlisting the help of large, national health plans to help track the safety of the vaccine.

The Post-Licensure Rapid Immunization Safety Monitoring (PRISM) system was described by Richard Platt, MD, from Harvard Pilgrim Health Care and Harvard Medical School, Boston, Massachusetts.

"Many H1N1 vaccine doses may be given by public providers and not captured in health plan data," he told the committee. "We are trying to develop the capability of linking state immunization registry exposure data to health plans membership data, which can provide us outcome data."

Participating health plans, which include Aetna, CIGNA, Humana, HealthCore, and WellPoint plans in California, New York, and Colorado, and Blue Cross Blue Shield in Michigan, will provide data on some 25 million people.

The state registries that are participating in PRISM are from Arizona, Florida, Georgia, Michigan, Minnesota, New York (as well as New York City), Pennsylvania, and Wisconsin, and these will provide data on an additional 14 million people.

The exchange of data between health plans and registries is a new experience for everyone, Dr. Platt noted.

To ensure that data sharing protects patient confidentiality, PRISM has been classified as a public health practice, not as research, "so there is no [internal review board] approval that is governing this," he said.

The various health plans and states are encouraged to use the Health Insurance Portability and Accountability Act public health exemption for exchange of protected health information. All person-level data will remain at the health plans after transformation to a standard format.

"This is a very robust and reassuring way to extract the information that is needed to support public health purposes while ensuring the privacy of the health information," he said.

PRISM started in September, and the first data should become available within 2 weeks, around early December, Dr. Pratt said.

"PRISM is enhancing vaccine safety by framing safety surveillance as a public health activity, by creating public–private collaborations for public health, by implementing methods for rapid analysis of data, and by developing methods for responding to findings," he concluded.

Saturday, November 21, 2009

Tamiflu

http://pediatrics.about.com/od/drugprofiles/p/05_tamiflu.htm

Tamiflu is a prescription antiviral medication that can be used to treat influenza infections (the flu) in children and adults, if their symptoms have started within the last day or two before starting to take Tamiflu. It can also be used to prevent the flu in children, teens and adults who have been exposed to the influenza virus.

What Tamiflu Is Used For:
Tamiflu is approved to treat the flu in adults and children over age 12 months.
It is also indicated as prophylaxis, or a preventative, against the flu for adults and children over age 12 months.

Tamiflu Facts:

the trade name for Tamiflu is oseltamivir phosphate
unlike other antiviral flu medications, such as Flumadine and Symmetrel, Tamiflu is effective against both type A and B strains of flu
Tamiflu helps to reduce your time with flu symptoms by about 1.3 days
Tamiflu is a neuraminidase inhibitor
there is no generic version of Tamiflu available yet and 10 capsules can cost over $80 if you have to pay full price

Other facts about Tamiflu:

Tamiflu is available as 75mg capsules and as a 12mg/ml tutti-frutti flavored Oral Suspension for children who can't swallow pills


some parents warn that the Oral Suspension is not a very good tasting medicine, so you might add extra flavoring, especially if your child does not take medicine easily
Tamiflu may be taken either with or without food


Tamiflu does not treat other flu-like viral infections, such as the stomach flu, colds, or RSV


Dosage of Tamiflu::
Treatment of Flu (all twice a day for 5 days)
Adults and teens over 13 take 75mg
The dosage for younger children who are 1 year and older depends on their weight:
<33lbs - 30mg - need 1 bottle
>33 to 51lbs - 45mg - need 2 bottles
>51 to 88lbs - 60mg - need 2 bottles
>88lbs - 75mg - need 3 bottles

Prevention of Flu
Adults and teens take 75mg once a day for 10 days
Children over age 1 take the same dose they would for treatment of the flu, but take it just once a day for 10 days

Tamiflu Side Effects:
The most common side effects in pediatric patients taking Tamiflu for the treatment of the flu include vomiting, abdominal pain, epistaxis (nosebleeds), ear disorders, and conjunctivitis (pinkeye).

Tamiflu is being investigated under the Best Pharmaceuticals for Children Act, because in a safety review, 'unusual neurologic or psychiatric events such as delirium, hallucinations,
However, the reports were almost all from children in Japan, where there were 12 deaths in pediatric patients, although the FDA 'can not conclude that there is a causal relationship between Tamiflu and the reported pediatric deaths.'

What You Need To Know:
Tamiflu should be started as soon as possible after a child develops flu symptoms, and at least within two days, or as soon as possible after you have been exposed to someone with the flu, if you have not had a flu shot.

Other important information:

Tamiflu is thought to be effective against the Bird Flu, leading some countries and individuals to create stockpiles of Tamiflu
A flu test can help to determine if your child's symptoms are caused by the flu, so that you can determine if Tamiflu will even be helpful.
Several shipments of fake or counterfeit Tamiflu pills have been seized recently, so if ordering Tamiflu on the internet, only buy Tamiflu from a reputable online pharmacy.


Sources:
Tamiflu Complete Product Information Sheet. Revised December 2005.
FDA Tamiflu Pediatric Adverse Events: Questions and Answers

Thursday, November 19, 2009

FDA Panel Recommends Prevnar 13 Vaccine for Approval

From Medscape Medical News

Fran Lowry

November 19, 2009 — The US Food and Drug Administration (FDA) advisory committee on vaccines and related biological products has given a near-unanimous endorsement of the pneumococcal vaccine Prevnar 13, saying it believes the new vaccine is effective and safe for the active immunization of children against serious systemic infection with Streptococcus pneumoniae.

Ten panel members voted yes, 1 voted no, and 1 abstained when asked whether the available data presented by Pfizer, the vaccine's sponsor, were adequate to support the effectiveness of Prevnar 13 when administered to infants and toddlers at ages 2, 4, 6, and 12 to 15 months to prevent invasive pneumococcal disease caused by serotypes in the vaccine.

The vaccine is to be given in 4 doses as an intramuscular injection.

Panel member Pamela McInnes, DDS, from the National Institute of Dental and Craniofacial Research, the National Institutes of Health, Bethesda, Maryland, said she thought the data that Pfizer presented were very convincing about the vaccine's efficacy. "I think we have to look at what I think are quite compelling data in terms of functional antibodies. I am very persuaded by that."

The panel also gave a near-unanimous thumbs up to the FDA's second question about whether they thought the evidence for the vaccine's safety was adequate.

However, Patricia Ferrieri, MD, professor of pediatrics and infectious diseases at the University of Minnesota Medical Center in Minneapolis, reminded the panel that they were inferring safety about Prevnar 13 from their experience with Prevnar 7. "I just want that on the record," she said.

The panel member who voted no, Vicky Debold, PhD, director of patient safety at the National Vaccine Information Center in Vienna, Virginia, and the consumer representative on the panel, said she was not convinced about the new vaccine's safety.

"I am concerned that we are discussing whether safety has been demonstrated here, when in fact the safety data are not complete. We're not looking at the full complement of data, and it is disconcerting to me to see that, as the number of doses increase, we were seeing an increase in the severity and frequency of adverse reactions," she said.

Prevnar 13 is composed of capsular polysaccharides derived from the 7 pneumococcal serotypes contained in Prevnar 7 (4, 6B, 9V, 14, 18C, 19F, and 23F) and from 6 additional pneumococcal serotypes (1, 3, 5, gA, 7F, and 19A).

Each capsular polysaccharide is individually conjugated to diphtheria CRM197 protein, and this prompted 1 panel member to ask about the potential for hyperimmunization.

Robert Munford, MD, from the National Institutes of Health, commented that today's children may be getting hyperimmunized with diphtheria toxin. "These kids are getting so much of this, and Prevnar 13 has twice the dose of CRM. Hyperimmunization can lead to autoimmune phenomena. Is the company planning to watch for such events in its postmarketing surveillance?"

The sponsor said that the company was planning to look for autoimmune diseases in its postmarketing surveillance.

The committee was also asked to discuss — but not to vote on — whether the data presented by the sponsor supported the effectiveness of Prevnar 13 for the prevention of otitis media. Despite arguments by Wyeth that the effect of its predecessor, Prevnar 7, was substantial, some panel members were not convinced.

"This is where I get mired," said Jose Romero, MD, professor of pediatrics at University of Arkansas, Little Rock. "There is no real correlate with protection for otitis media. You can't really extrapolate from the data you have given that you get a good antibody response that would predict that you're not going to have otitis media if you get this vaccine. This is more of a black-box issue."

Pablo Sanchez, MD, from the University of Texas Southwestern Medical Center in Dallas, agreed. "We are being asked to say that this vaccine is efficacious for otitis media based on other data, and we have to extrapolate here. I would like to see more data on this."