Avosentan Reduces Urinary Protein Loss but May Cause Serious Side Effects, Says Study

The drug avosentan substantially reduces urinary protein loss in people with type 2 diabetes and kidney disease, but the drug causes serious side effects, according to a study appearing in an upcoming issue of the Journal of the American Society Nephrology (JASN). The results suggest that lower doses of avosentan may have a more favorable risk/benefit ratio for patients.

Despite aggressive treatments, individuals with kidney disease often experience proteinuria, or excessive loss of protein in the urine, which increases kidney damage. A key factor in the development of proteinuria is endothelin, which by constricting blood vessels and raising blood pressure, causes the kidney’s filtering function to deteriorate. Researchers suspect that blocking the endothelin peptide could be a promising new treatment strategy for patients who develop proteinuria. Endothelin antagonists such as oral avosentan are already available and are prescribed for patients with cardiovascular conditions.

Johannes Mann, MD (Schwabing General Hospital and KfH Kidney Centre, in Munchen, Germany) and his colleagues examined the effects of avosentan on proteinuria and kidney function in patients with type 2 diabetes and kidney disease through a multicenter, multinational, double-blind, controlled trial. The Avosentan ASCEND study enrolled 1392 patients already being treated for kidney disease and randomized them to receive avosentan 25 mg, avosentan 50 mg, or placebo.

While avosentan at either dose lowered patients’ urinary protein excretion by 40%-50% (compared with less than 10% in patients taking placebo), individuals taking the drug experienced a high incidence of serious, sometimes life-threatening side effects. These included complications of fluid overload such as pulmonary edema, as well as congestive heart failure. In addition, there were more deaths in the groups taking avosentan (21 and 17) than in the group taking placebo (12).

Dr. Mann noted that the findings from the ASCEND trial highlight the risks and potential benefits of endothelin antagonists in kidney disease patients with proteinuria and will help investigators design future studies to test the drugs’ potential. Specifically, lower doses of avosentan may generate more positive results.

Speedel Pharma Ltd, Switzerland, sponsored the study and appointed the contract research organization Quintiles Ltd for study set-up, initiation, management, and analysis. (Disclosures: Susan Kuranoff and Thomas Littke were employees of the sponsor, and all other authors have consulting funds from Speedel Pharma Ltd.

Source: Journal of the American Society Nephrology, “Avosentan for Overt Diabetic Nephropathy,” online ed. (February 18, 2010, doi 10.1681/ASN.2009060593); American Society of Nephrology (ASN).

Rituxan Approved to Treat Chronic Lymphocytic Leukemia

The U.S. Food and Drug Administration (FDA) has approved Rituxan (rituximab) to treat certain patients with chronic lymphocytic leukemia (CLL), a slowly progressing blood and bone marrow cancer.

Rituxan, an anti-cancer drug, is intended for patients with CLL who are beginning chemotherapy for the first time and for those who have not responded to other cancer drugs for CLL. Rituxan is administered with two other chemotherapy drugs, fludarabine and cyclophosphamide.

CLL primarily affects people older than 50 and arises from a group of white blood cells known as B-cells—part of the body’s immune system. Each year, about 16,000 people are diagnosed with and 4,400 die from CLL.

“Rituxan is the third drug approved for the treatment of CLL since 2008 and underscores FDA’s commitment to expediting the development and approval of drugs for patients with serious and life-threatening diseases,” said Richard Pazdur, M.D., director, Office of Oncology Drug Products in the FDA’s Center for Drug Evaluation and Research.

FDA approved Arzerra (ofatumumab) in October 2009 for patients whose cancer is no longer being controlled by other forms of chemotherapy and Treanda (bendamustine) in March 2008 for patients with CLL who had not received prior treatment.

Rituxan is a monoclonal antibody. It is manufactured through biotechnology methods rather than by the human body’s own immune system. The drug binds to the surface of cancer cells, making it easier for the patient’s immune system to attack the cancer cell as if it were a foreign pathogen.

The safety and effectiveness of Rituxan was evaluated in two studies that measured progression-free survival, defined as the time a patient in the study lived without the cancer progressing.

In one study of 817 patients who had not received any prior chemotherapy, progression-free survival was eight months longer for those receiving Rituxan plus chemotherapy than for those who received chemotherapy alone. In another study of 522 persons whose cancer had progressed following other chemotherapy drugs, progression-free survival was five months longer for those who received Rituxan plus chemotherapy.

The FDA analyzed the data on patients 70 years of age and older who had received Rituxan and found no evidence that adding the drug to chemotherapy benefitted elderly patients compared to receiving chemotherapy alone. However, there was also no evidence that Rituxan was harmful to elderly patients.

Rituxan carries a Boxed Warning for infusion reactions, which can occur during infusion or within 24 hours afterwards. Some 59 percent of patients treated with Rituxan for CLL experienced an infusion reaction that resembled an allergic reaction (e.g., hives, low blood pressure, chills, fever, and nausea).

A decrease in infection-fighting, normal white blood cells was also commonly observed in patients enrolled in the Rituxan clinical trials.

Other Boxed Warnings for Rituxan include rashes and sores in the skin and mouth; progressive multifocal leukoencephalopathy (PML), a brain infection that is generally fatal; and tumor lysis syndrome, which results from the death of a large number of tumor cells in a short period of time. When the tumor cells are killed by the drug, they release toxins into the bloodstream that can cause acute kidney injury and increase the levels of potassium and phosphate in the blood.

Rituxan is manufactured by San Francisco based-Genentech, a member of the Roche Group.

Source: FDA (2/18/2010)

Robotic Surgery Faster in Repairing Kidney Blockages

A comparison of two types of minimally invasive surgery to repair kidney blockages that prevent urine from draining normally to the bladder found that robot-assisted surgery was faster and resulted in less blood loss and shorter hospital stays.

Reporting in the Canadian Journal of Urology, Ashok Hemal, M.D., a urologic surgeon from Wake Forest University Baptist Medical Center, compared laparoscopic and robot-assisted surgery for repairing the blockage, known as uretero-pelvic junction obstruction. Following the patients for 18 months showed that both options were equally successful, but the robot-assisted technique had several advantages.

On average, robot-assisted surgery was 50 percent faster (98-minute versus 145-minute average), resulted in 60 percent less blood loss (40ml versus 101ml average), and required a two-day hospital stay, versus 3.5 days for laparoscopic surgery.

“This was one of the first studies where a single surgeon at one center performed both types of surgery and compared the results,” said Hemal, director of the Robotic and Minimally Invasive Urologic Surgery Program at Wake Forest Baptist. “It allows for a more accurate comparison of surgical options than multiple physicians performing the surgeries. The results showed that robot-assisted surgery had significant advantages for this condition. It is also generally easier for surgeons to learn.”

All 60 patients had a procedure known as pyeloplasty that involves reconstructing the narrow area where part of the kidney meets the ureter, the tube that carries the urine from the renal pelvis into the bladder. Blockages in this area can be the result of birth defects or, in adults, from injury, previous surgery or disorders that can cause inflammation of the upper urinary tract.

Previously the repair required a large incision. New technology led to minimally invasive approaches that require only small incisions — laparoscopic surgery, in which the surgeon directly manipulates a viewing device and operating instruments inserted into the abdomen, and robot-assisted surgery, in which the surgeon sits at a console and uses hand and finger movements to control centimeter-size instruments while viewing the surgical site on a screen.

Various studies have reported on the results of the options, but this is one of the first studies in which a surgeon with expertise in both options compared them. Hemal treated 30 patients with laparoscopic surgery and 30 with robot-assisted surgery.

“The evolution of laparoscopic surgery in urology has been limited because it is technically challenging and requires the surgeon to be proficient in advanced suturing,” said Hemal. “Robot-assisted surgery offers a way of overcoming some of the major impediments of laparoscopic surgery. This study shows the two options are equally effective and that robot-assisted surgery has several advantages.”

Hemal’s colleagues on the report are Satyadip Mukherjee, M.D., and Kaku Singh, M.D., both with the All India Institute of Medical Sciences in New Delhi, where the surgeries were performed.

Source: Canadian Journal of Uroloygy, Wake Forest University Baptist Medical Center (2/18/2010)

Natural Compound Sceptrin Reduces Cancer Cell Motility

Scientists have discovered that the natural compound sceptrin, which is found in marine sponges, reduces cancer cell motility (movement) and has very low toxicity. Metastasis is one of the deadliest aspects of cancer, so restricting aberrant cell movement is an important step towards advancing treatments. The research was was conducted by investigators at Sanford-Burnham Medical Research Institute (Sanford-Burnham, formerly Burnham Institute for Medical Research) led by Kristiina Vuori, M.D., Ph.D., and published online in ACS Chemical Biology, in collaboration with Phil S. Baran, Ph.D., of The Scripps Research Institute.

The team tested sceptrin in multiple tumor cell types, including cervical, breast and lung cancers. Sceptrin restricted motility in all cell lines. Further tests showed the compound works by limiting the cells’ ability to contract, a critical function for cell motility. The researchers also found that sceptrin synthesized in the laboratory was just as effective at combating motility as the naturally-derived compound.

Given the recently achieved synthesis of sceptrin in multi-gram quantities by the Baran laboratory, sceptrin could prove to be an attractive lead molecule for further preclinical testing and development for therapeutic purposes,” said Dr. Vuori. It may also prove to be a useful research tool in order to elucidate the mechanisms involved in cell motility.”

The researchers cultured growing cancer cells with growth factor to encourage motility. These cells were treated with varying amounts of sceptrin, which was found to be more effective at increased concentrations. Subsequently, the team conducted apoptosis and cell proliferation studies to determine whether these mechanisms accounted for the decrease in motility of sceptrin-treated cells. Other assays determined that sceptrin limits motility by reducing cell contractility.

Souce: ACS Chemical Biology, Sanford-Burnham Medical Research Institute (2/18/2010)

Elderly with Untreated Vision Problem More Likely to Develop Alzheimer’s

Elderly people with visual disorders that are left untreated are significantly more likely to develop Alzheimer’s disease — the most common form of dementia, according to a University of Michigan Health System study.

The study used Medicare data and shows that those with poor vision who visited an ophthalmologist at least once for an examination were 64 percent less likely to develop dementia.

The study appears online ahead of print in the American Journal of Epidemiology and may draw a new picture of poor vision as predictor of dementia rather than as a symptom after the diagnosis.

“Visual problems can have serious consequences and are very common among the elderly, but many of them are not seeking treatment,” says lead author Mary A.M. Rogers, Ph.D, research assistant professor of internal medicine at the U-M Medical School and research director of the Patient Safety Enhancement Program at the U-M Health System and the Ann Arbor VA Medical Center.

For the study, Rogers and her colleague Kenneth M. Langa, M.D., Ph.D., professor of internal medicine at U-M Medical School, analyzed data from the nationally representative Health and Retirement Study and records from Centers for Medicare and Medicaid Services.

”Our results indicate that it is important for elderly individuals with visual problems to seek medical attention so that the causes of the problems can be identified and treated,” Rogers says.

The types of vision treatment that were helpful in lowering the risk of dementia were surgery to correct cataracts and treatments for glaucoma, retinal disorders and other eye-related problems.

Proper vision is a requirement for many of the activities that previously have been found to lower the risk of Alzheimer’s disease. These include reading, playing board games, other mentally stimulating activities, social networking, as well as physical activity such as walking and routine exercising. A visual disorder may interfere with normal mobility and may also hinder a person’s ability to participate in such activities.

“Many elderly Americans do not have adequate health coverage for vision, and Medicare does not cover preventative vision screenings for most beneficiaries,” Rogers says. “So it’s not unusual that the elderly receive vision treatment only after a problem is severe enough to warrant a visit to the doctor when the problem is more advanced.”

According to a survey conducted by the National Eye Health Education Program, less than 11 percent of respondents understood that there are no early warning signs for eye problems such as glaucoma and diabetic retinopathy.

However, vision problems and blindness are among the top 10 disabilities among adults and can result in a greater tendency to experience other health conditions or even to die prematurely.

“While heart disease and cancer death rates are continuing to decline, mortality rates for Alzheimer’s disease are on the rise,” says Rogers. “So if we can delay the onset of dementia, we can save individuals and their families from the stress, cost and burden that are associated with Alzheimer’s disease.”

The study was based on the surveys and medical information from 625 people compiled from 1992-2005. Only 10 percent of Medicare beneficiaries who developed dementia had excellent vision at the beginning of the study, while 30 percent of those who maintained normal cognition had excellent vision at the onset of the study.

One in five Americans who are over age 50 report experiencing a visual impairment, according to the U.S. Centers for Disease Control and Prevention. Approximately 5 million Americans have Alzheimer’s disease and the number has doubled since 1980. It is expected to be as high as 13 million by 2050.

Source: American Journal of Epidemiology,/em> 2010 Feb. 11; doi:10.1093; University of Michigan

Combination Hormone Therapy (CHT) Poses Heart Disease Risk for Postmenopausal Women

New analyses from the Women’s Health Initiative (WHI) confirm that combination hormone therapy increases the risk of heart disease in healthy postmenopausal women. Researchers report a trend toward an increased risk of heart disease during the first two years of hormone therapy among women who began therapy within 10 years of menopause, and a more marked elevation of risk among women who began hormone therapy more than 10 years after menopause. Analyses indicate that overall a woman’s risk of heart disease more than doubles within the first two years of taking combination HT.

The difference in the initial level of risk does not appear related to age, based on findings that the increased risk of heart disease was similar between women in their 50s on combination hormone therapy and women in their 60s.

“Today, most women who take hormone therapy for menopausal symptoms begin therapy shortly after menopause. Based on today’s report, even these women appear to be at increased risk of heart disease for several years after starting combination hormone therapy,” noted Susan B. Shurin, M.D., NHLBI acting director. “It is clearer than ever that women who are considering postmenopausal hormone therapy for menopausal symptoms should discuss their risk of heart disease and other risks – such as breast cancer, stroke, and dangerous blood clots – with their doctors before starting therapy.”

Jacques E. Rossouw, M.D., chief of the NHLBI Women’s Health Initiative Branch and a coauthor of the paper, added, “Although the number of recently menopausal women who would be expected to suffer a heart attack during the first years of combination hormone therapy is small, the risk is likely to be real. Our findings continue to support FDA recommendations that postmenopausal hormone therapy should not be used for the prevention of heart disease.”

Combination hormone therapy includes progestin in combination with estrogen. Adding progestin is known to prevent endometrial cancer in women with a uterus. Today’s findings do not apply to women who have had a hysterectomy and take estrogen-only hormone therapy. Similar analyses on the results of the clinical trial of estrogen only therapy are planned.

Researchers from the Harvard School of Public Health and the NHLBI reanalyzed data from the landmark WHI clinical trial of the effects of combination hormone therapy in 16,608 postmenopausal women with an intact uterus, ages 50 to 79 years (average age of 63) at enrollment.

In the new analyses, the researchers compared the effects of hormone therapy on heart disease risk among women who began hormone therapy within 10 years of menopause and women who began therapy more than 10 years after menopause. The researchers used models that adjusted for adherence, or the actual amount of medication that participants took during the study. They also studied the effects of hormone therapy on heart disease over time (up to eight years). In addition, they compared the findings with similar analyses of 34,575 women in the Nurses Health Study, an observational study with an average follow-up of 9.3 years. The researchers report similar effects of hormone therapy from both studies.

In the WHI clinical trial of estrogen-plus-progestin, 8,506 participants were randomly assigned to receive a combination of estrogen (0.625 milligrams of conjugated equine estrogens per day) plus progestin (2.5 mg of medroxyprogesterone acetate), and 8,102 women were given placebo (inactive pill). The study was stopped in 2002 after an average of 5.6 years of treatment due to an increase in breast cancer in the women on hormone therapy. Compared to women on placebo, women on combination hormone therapy were also at increased risk of stroke, dangerous blood clots, and heart disease, while their risk of colorectal cancer and hip fractures was lower.

Overall, among the 8,506 women assigned to combination hormone therapy during the study, there were 188 cases of coronary heart disease (80 in the first two years), compared to 147 heart disease cases (51 in the first two years) among the 8,102 women on placebo. When adjusted for adherence, the analysis shows that women on combination hormone therapy were about 2.4 times more likely to develop heart disease in the first two years. At eight years, the women on combination hormone therapy were 69 percent more likely to develop heart disease.

The new analyses also showed:

Women who were within 10 years of menopause had a trend toward an increased risk of heart disease, with a 29 percent higher risk at two years from the start of hormone therapy. Although the increased risk of heart disease was not statistically significant, this finding is consistent with a similar analysis of data from the larger Nurses Health Study.

Women who started combination hormone therapy less than 10 years after menopause remained at increased risk of heart disease on average for about six years, after which those in the treatment group appeared to have a lower risk of heart disease compared to similar women who were not on combination hormone therapy. In the nurses study, the initially increased risk on combination hormone therapy changed toward lower risk of heart disease after about three years.

In contrast, women who started hormone therapy 10 years or more after menopause were nearly 3 times more likely to develop heart disease within the first two years of treatment compared to women on placebo. These women continued to be at increased risk of heart disease throughout the 8 years of follow-up.

It is not clear why the heart disease risk appears to be higher in women who start combination hormone therapy a decade after menopause than in women who begin combination hormone therapy within 10 years after menopause. According to Sengwee Toh, Sc.D., lead author of the paper and now an instructor in the Department of Population Medicine, Harvard Medical School, “This study suggests that the risk of heart disease may depend on when women start their combination hormone therapy and how long they are on this treatment. Future investigations should consider both of these aspects.”

The WHI is a major 15-year research program designed to address the most frequent causes of death, disability, and poor quality of life in postmenopausal women: cardiovascular disease, cancer, and osteoporosis. The principal findings from the two WHI hormone therapy trials, which studied 27,347 postmenopausal women on estrogen plus progestin, estrogen-alone, or placebo, found that the overall risks of long-term use of hormone therapy outweigh the benefits. Both of these trials were stopped early because of increased health risks and failure to prevent heart disease, a key question of the studies.

The NHLBI collaborates on the WHI with the National Cancer Institute, the National Institute of Arthritis and Musculoskeletal and Skin Diseases, the National Institute on Aging, and the Office of Research on Women’s Health, all parts of the NIH. Wyeth-Ayerst Research provided the medication and placebo for the hormone study.

Source: em>Annals of Internal Medicine (2/16/2010); National Institutes of Health (2/15/2010)

Knee and Hip Replacement Pain: A New Approach to Pain Management

Patients undergoing knee or hip replacements recover more quickly when treated with targeted pain-blocking medications that may eliminate the need for general anesthesia during surgery and intravenous narcotics drugs after surgery.

A decade ago, patients undergoing hip or knee replacements were almost exclusively given general anesthesia during surgery and intravenous narcotic pain medications afterward. This approach works for most people and still is commonly practiced. But both general anesthesia and intravenous narcotic drugs can cause nausea, vomiting, grogginess, decreased bowel function and other side effects.

In the early 2000s, Mayo Clinic anesthesiologists began developing new anesthesia protocols for joint replacement surgery that used known anesthetic and pain relief techniques in new combinations. Their goal was to eliminate the need for general anesthesia and intravenous narcotics and the resulting side effects.

The new procedures may vary but typically involve:

A choice: Even with the new protocols, patients may choose regional anesthesia, where the lower half of the body is numbed, or general anesthesia.

Oral pain medications early on: A combination of oral narcotic pain medications are given prior to surgery. Oral narcotics have fewer side effects than narcotics given intravenously. This technique is helpful for recovery whether general or regional anesthesia is used.

Sedation: Sedative drugs given before surgery help patients using regional anesthesia nap during the procedure, but not lose consciousness.

Nerve blocks: Through a catheter, a continuous infusion of numbing medicine is pumped near the surgery site for 48 hours. Nerve blocks are performed in conjunction with general or regional anesthesia.

Oral pain medications after surgery: For more than 95 percent of patients, pain that occurs after the nerve blocks are removed can be managed with oral pain medications such as acetaminophen (Tylenol, others), tramadol (Ultram, others) or oxycodone. Intravenous narcotic medications are used as a last resort.

Patients who receive regional anesthesia report significantly less pain after surgery than those receiving general anesthesia and intravenous narcotics. These patients are out of bed sooner, begin physical therapy sooner and leave the hospital one to two days before patients who were given general anesthesia and intravenous narcotics. With the newer protocols, patients may still experience typical side effects including nausea and vomiting, but to a lesser degree than with the older anesthesia methods.

Another benefit is that regional anesthesia protocols make surgery an option for older adults with more complicated conditions. A decade ago, older adults often were not considered candidates for surgery because they would have fared poorly with older anesthesia techniques.

Doctors report few downsides to these newer pain management approaches. Nerve injury is a rare potential complication. For most people, the regional anesthesia protocols are a change for the better, resulting in less pain, fewer complications and a quicker recovery.

Source: Mayo Clinic (2/10/2010)

Barriers to Screening May Increase Colorectal Cancer Deaths

Colorectal cancer is the second leading cause of cancer-related deaths in the United States. Despite evidence and guidelines supporting the value of screening for this disease, rates of screening for colorectal cancer are consistently lower than those for other types of cancer, particularly breast and cervical. Although the screening rates in the target population of adults over age 50, have increased from 20-30 percent in 1997 to nearly 55 percent in 2008 — the rates are still too low. An NIH state-of-the-science panel was convened this week to identify ways to further increase the use and quality of colorectal cancer screening in the United States.

“We recognize that some may find colorectal cancer screening tests to be unpleasant and time-consuming. However, we also know that recommended screening strategies reduce colorectal cancer deaths,” said Dr. Donald Steinwachs, panel chair, and professor and director of the Health Services Research and Development Center at the Johns Hopkins University. “We need to find ways to encourage more people to get these important tests.”

The panel found that the most important factors associated with being screened are having insurance coverage and access to a regular health care provider. Their recommendations highlighted the need to remove out-of-pocket costs for screening tests.

Given the variety of tests available, the panel emphasized that informed decisions incorporating personal preferences may help reluctant individuals determine which test’s combined attributes — invasiveness, frequency, and required preparation — are preferable to them, helping them identify and obtain the most palatable test. For example, an individual may choose a more invasive test requiring less frequent follow-up or a less invasive test requiring more frequent follow-up.

Noting differences in screening rates across racial and ethnic groups, socioeconomic status, and geographic location, the panel emphasized the need for targeted strategies for specific subgroups. Compared with non-Hispanic whites, Hispanics are less likely to be screened.

The panel also noted that if efforts to increase utilization are successful, there will be a greater demand for colorectal cancer screening services. Available capacity involves not only facilities and appropriately trained providers, but also support for informed decision making, resources to coordinate screening services and communicate results effectively, and enhanced monitoring practices to ensure that positive results are followed up with colonoscopy. Depending on the scale of increases in screening rates, there may be a need to increase local and national capacity.

In addition to increasing first-time screening rates, the panel also identified the need to ensure that individuals return for subsequent testing at the recommended intervals. A variety of colorectal cancer screening tests are available and different guidelines recommend them at different intervals.

The conference was sponsored by the NIH Office of Medical Applications of Research and the National Cancer Institute along with other NIH and Department of Health and Human Services components. This conference was conducted under the NIH Consensus Development Program, which convenes conferences to assess the available scientific evidence and develop objective statements on controversial medical issues.

The 13–member conference panel included experts in the fields of cancer surveillance, health services research, community-based research, informed decision-making, access to care, health care policy, health communication, health economics, health disparities, epidemiology, statistics, thoracic radiology, internal medicine, gastroenterology, public health, end-of-life care, and a public representative. A complete listing of the panel members and their institutional affiliations is included in the draft conference statement.

In addition to the material presented at the conference by speakers and the comments of conference participants presented during discussion periods, the panel considered pertinent research from the published literature and the results of a systematic review of the literature. The systematic review was prepared through the Agency for Healthcare Research and Quality Evidence-based Practice Centers (EPC) program, by the RTI International-University of the North Carolina Evidence-based Practice Center. The EPCs develop evidence reports and technology assessments based on rigorous, comprehensive syntheses and analyses of the scientific literature, emphasizing explicit and detailed documentation of methods, rationale, and assumptions.

Source: National Institutes of Health (Feb. 4, 2010)

NIH Clinical Center Devices Will Automatically Record Radiation Exposure

Radiology and Imaging Sciences at the National Institutes of Health Clinical Center has taken a significant step to further safeguard clinical research patients at the NIH Clinical Center who are exposed to radiation during certain imaging tests. Computed tomography (CT) and positron emission tomography (PET)/CT equipment purchased by the Clinical Center will now be required to routinely record radiation dose exposure in a patient’s hospital-based electronic medical record.

“When a hospital or clinic patient receives a medication or a treatment, it is routinely recorded in the patient’s medical record,” said John I. Gallin, M.D., director of the Clinical Center, NIH’s clinical research hospital in Bethesda, Md. “The Clinical Center’s approach is an important first step in making it possible to more easily document and track information about a patient’s exposure to radiation.”

Today, electronic radiology information systems in hospitals generally do not collect or report radiation exposures. “CT and PET/ CT scanners do not currently forward data on radiation dose to our radiology information systems,” said Dr. David A. Bluemke, M.D., Ph.D. Bluemke is director of Radiology and Imaging Sciences at the Clinical Center.

The risk of exposure to low doses of medical radiation from diagnostic medical-imaging tests isn’t known, but very high radiation doses have the potential to cause cancer. The ability to keep track of an individual’s exposure to radiation through routine imaging tests is needed so that researchers can begin to determine if these exposures pose a health risk.

“The National Council on Radiation Protection and Measurements reported recently that Americans received seven times more radiation exposure from medical tests in 2006 than was the case in the 1980s,” said Ronald Neumann, M.D., chief of nuclear medicine and deputy associate director for imaging sciences at the Clinical Center. “CT and cardiac nuclear medicine studies accounted for much of this increased medical radiation exposure.”

Ultimately, radiation dosage could become a standard element of a universal electronic medical record used to assess radiation risk from life-long medical testing, the Clinical Center radiologists said. “Recording radiation dose is technically possible and an ethical imperative, ” Neumann said.

“The NIH Clinical Center also will require that newly purchased equipment allows patients to record their radiation dose exposure in their own personal health record,” Bluemke added. Online resources to help individuals organize their health information as a personal medical record are becoming more prevalent. Currently, patients can easily receive their diagnostic imaging studies records on CD-ROM, Bluemke said. The NIH Clinical Center’s imaging program will work with vendors who supply Clinical Center imaging equipment to develop software tools to extract the examination type, date, and radiation dose exposure from the CD-ROM, for uploading to a personal health record. As both the American College of Radiology and the Radiological Society of North America have recommended, patients should keep a record of their X-ray history.

About 25,000 CT and 1,250 PET/CT scans are performed at the Clinical Center each year as part of NIH research protocols. The clinical research hospital currently houses five CT scanners, and two PET/CT scanners.

Source: NIH, August 17, 2009