SAN DIEGO — Patients with advanced chronic obstructive pulmonary disease (COPD) may not be getting effective treatment for dyspnea toward the end of life, researchers reported here.

A retrospective review of administrative claims data showed that patients with advanced COPD were significantly less likely to receive morphine in the last three months of life than those with terminal lung cancer (OR 2.36, 95% CI 1.52 to 3.67), according to Donna Goodridge, PhD, of the University of Saskatchewan in Saskatoon.

They were also less likely to receive palliative care at home (2.8% versus 37.4%, P<0.005), and palliative care itself was associated with an increased likelihood of receiving morphine in the months before death (OR 2.64, 95% CI 1.72 to 4.06), Goodridge said at the American College of Chest Physicians meeting.

She said the findings underscore the need for further research.

“We need to explore the efficacy and safety of opioid use for relief of dyspnea at the end of life in persons with COPD,” she said. “And we also need to assess patient, family, and clinician experiences with opioid use for dyspnea at the end of life for those people dying of COPD.”

Dyspnea is the most burdensome symptom and a source of disability in end-stage COPD, Goodridge said, and it doesn’t respond to conventional therapies in 56% to 98% of patients.

Opioids are commonly used to treat dyspnea in patients with terminal cancer, but Goodridge said she was surprised to see that there wasn’t a very good management strategy in COPD.

Low doses of opioids could relieve dyspnea in COPD patients by reducing total ventilation, increasing ventilatory efficiency with exercise, reducing responses to hypoxia/hypercapnia, and reducing the drive to breathe, Joanne Young, a registered respiratory therapist at Dalhousie University in Halifax, Nova Scotia, and colleagues noted in a separate presentation at the meeting.

The drugs might also affect bronchoconstriction, they said in a poster session.

A 2002 meta-analysis in Thorax found that both oral and parenteral opioids had a positive effect on breathlessness (P=0.0008) in all patient groups, including those with COPD. But how often patients with COPD are treated with opioids has not been well studied.

So Goodridge and her colleagues examined administrative data from the Saskatchewan Health Ministry on all patients who died during 2004 of lung cancer (433 patients) or COPD (602 patients).

Patients with COPD were less likely to die in the hospital and more likely to die in a long-term care facility (P<0.05).

In the last three months of life, more patients with lung cancer received a prescription for morphine (31% versus 9%).

The strongest predictor of receiving morphine was palliative care at home, which, though more frequent in patients with lung cancer, was surprisingly underused in both groups, Goodridge said.

“This is something that I think we may need to explore further,” she said.

The study by Young and colleagues explored possible reasons at the clinical level for the infrequent use of opioids in patients with advanced COPD.

The researchers interviewed 10 family physicians and eight respiratory therapists in the province of New Brunswick about their attitudes toward prescribing the medications for the relief of dyspnea.

Although the clinicians all agreed that the control of dyspnea was the biggest challenge in treating patients with end-stage COPD, there was reluctance in using opioids unless death was imminent.

They cited concerns about respiratory depression, as well as about a lack of education and guidance from professional societies.

Two younger family physicians who received training in palliative care during their residencies expressed more comfort in using opioids for these patients.

Like Goodridge, Young and colleagues called for further research regarding the use of opioids for relieving dyspnea at the end of life in patients with COPD.

The study by Young and colleagues received funding from the Atlantic Health Sciences Corporation Health Promotion and Research Fund.

None of the authors of either of the studies reported any conflicts of interest.

STIRLING, England, Jan. 23 — To the surprise of few, consumption of cranberry products has been found by a systematic review to be protective against urinary tract infections.

Ten randomized controlled trials included in the review determined that cranberry products reduced the annual incidence of UTIs by 39% in women with a history of recurrence, Ruth Jepson, of the University of Stirling, and Jonathan Craig, M.D., of the University of Sydney in Australia, reported in a Cochrane review.

For these women, cranberries demonstrated clear-cut infection-fighting, the investigators reported. The benefits in other groups were less certain.

“Overall, the evidence ??¦ indicates that cranberry products can be effective in reducing UTIs,” the authors concluded. “However, it may only be effective in certain subpopulations.”

“Furthermore, there is no clear evidence as to the amount and concentration that needs to be consumed, and the length of time for the intervention to be most effective,” they added.

Moreover, most studies using cranberry juice had high dropout rates, suggesting that drinking considerable amounts of cranberry juice over a long period may not be acceptable. For this reason, the authors suggest that “further studies of cranberry capsules/tablets or other cranberry products, therefore, are also needed.”

Cranberry products, usually juice, have been used for years as a nonprescription approach to prevention of urinary tract infections. Though almost 90% water, cranberries also contain quinic acid, malic acid, and citric acid, as well as glucose and fructose.

No definitive mechanism of action has been identified to explain cranberries’ potential to ward off UTIs. The most common explanation is that cranberries prevent bacteria from adhering to the uroepithelium of the bladder, thereby blocking the ability of Escherichia coli to infect the urinary mucosa.

In an effort to clarify cranberry products’ potential to prevent UTIs, the authors conducted a literature search to identify all randomized controlled trials of cranberry juice or other cranberry-containing products versus placebo, no treatment, or any other treatment. The search yielded 10 studies involving 1,049 participants.

In seven of the 10 studies, cranberry or cranberry/lingonberry juice was compared with placebo juice or water. Four studies evaluated cranberry tablets versus placebo (including one study that evaluated cranberry juice and tablets).

Overall, cranberry-derived products significantly reduced the 12-month incidence of UTIs versus placebo or control (relative risk: 0.65, 95% CI: 0.46 to 0.90). Cranberry products reduced the risk of UTI by 39% in women with a history of recurrent UTI (95% CI: 0.40 to 0.91). Studies of older men and women demonstrated a trend toward a beneficial effect, but the result did not achieve statistical significance (RR: 0.51, 95% CI: 0.21 to 1.22).

In patients with neuropathic bladder, cranberry treatment arms had a slight increase in the risk of UTI, but the difference was not significant (RR: 1.06, 95% CI: 0.51 to 2.21).

The study was supported by the Nuffield Trust.

The authors declared no conflicts.

Primary source: Cochrane Database of Systematic Reviews

Source reference:

Jepson RG, Craig JC, “Cranberries for preventing urinary tract infections (review)” Cochrane Database Syst Rev 2008, Issue 1. Art. No.: CD001321. DOI: 10.1002/14651858.CD001321.pub4.

Drivers with hemianopia may be more likely to hit pedestrians than those who can see both halves of their visual field, road simulation tests affirmed.

Detection of pedestrians on the blind side ranged from a low of 6%, largely among older drivers, to a high of 100%, found Alex R. Bowers, PhD, of Schepens Eye Research Institute at Harvard, and colleagues.

The overall results were not encouraging for a return to driving with homonymous hemianopia — loss of half the field of vision on the same side in each eye — typically after a stroke or other trauma to the visual pathways, Bowers’ group reported in the November issue of Investigative Ophthalmology & Visual Science.

But an individual approach to revoking driver’s licenses is warranted, given the wide variability in ability to compensate for visual field loss, they said.

One participant in the road simulator study detected 86% of deep blind-side pedestrians along the roadway, a level similar to drivers with normal vision that “may represent compensation ability consistent with safe driving,” the researchers noted.

Although her detection rates for pedestrians in intersections was only 50% overall, specific training in scanning at intersections could allow this 31-year-old stroke patient to return to driving, Bowers’ group said.

“Intersections are challenging, even for drivers with a full field of vision,” but those with hemianopia need to learn how far into their blind side they need to scan by moving their eye far enough for the remaining field of vision to see all areas, they noted.

The pedestrian detection results suggested that drivers with hemianopia need training to scan at least 90° to the blind side and to check the more central areas of the intersection before making a turn, the authors wrote.

“Our results underscore the importance of assessing fitness to drive of people with homonymous hemianopia on an individual basis, either on-road or in a driving simulator, using a test route that includes sufficient opportunities for the evaluation of reactions to potential blind-side hazards,” they added.

In 22 states, people with hemianopia are prohibited from driving, a practice that limits independence, employment, and quality of life, the authors noted. Some European countries have begun licensing of those who can successfully complete a specialized road test, but recent studies based on these tests have produced conflicting results.

So Bowers’ group used a driving simulator to assess performance of 12 people with complete homonymous hemianopia but no cognitive decline or visual neglect, comparing them to 12 controls with normal vision and matched for age, sex, and years of driving experience.

After 120 minutes of city and rural highway “driving,” detection of pedestrians along the roadway was significantly lower in hemianopia patients on their blind side than it was with controls (P<0.001 at both large and small eccentricities).

Detection of blind side pedestrians in intersections ranged from 8% to 55%, with averages that were significantly lower than controls for left-hand turns (P≤0.01) though not for right-hand turns.

Highway driving produced poorer blind-side detection rates in drivers with hemianopia, supporting license restrictions that prohibit visually-impaired people from driving on highways, the researchers said.

Older age was the only predictor of detection performance. Older drivers had poorer detection of blind-side pedestrians in the roadway (small eccentricity P=0.009 and large eccentricity P=0.025), and pedestrians in the roadway on either side among those with normal vision (pooled P=0.006).

Overall, the blind-side response times were two standard deviations longer than average for drivers with normal vision (P<0.001). However, all but two hemianopia-affected drivers fell within the 2.5-second minimum between perception and braking recommended by the American Association of State Highway and Transportation Officials.

“Longer response times may compromise safety, but it is the failure to detect that is the more critical safety issue when evaluating fitness to drive,” the researchers noted.

One limitation of the study was use of pedestrians in intersections as a surrogate for vehicle detection, which may have underestimated detection rates compared with a moving car, they said.

The study was supported by grants from the National Institutes of Health. The researchers reported no conflicts of interest.

EDMONTON, Alberta, Feb. 5 — A mixture of helium and oxygen allowed patients with chronic obstructive pulmonary disease to increase their exercise capacity, found researchers here.

In a randomized crossover study, a mixture of 40% oxygen and 60% helium improved exercise capacity by a factor of nearly 2.5 compared with air, reported Neil Eves, Ph.D., of the University of Edmonton, and colleagues, in the February issue of the American Journal of Respiratory and Critical Care Medicine

The mixture, dubbed helium-hyperoxia, also improved exercise capacity compared to two other gas mixtures — hyperoxia (40% oxygen and 60% nitrogen) and normoxic helium (21% oxygen and 79% helium) — that are known to be beneficial in COPD, Dr. Eves.

“If patients were to breathe helium-hyperoxia in a rehabilitation setting, they could potentially perform a lot more exercise,” Dr. Eves said in a statement, “which might improve their exercise capacity, fitness level and as a result, quality of life.”

The improvement arises, the researchers said, because of a reduction in the dynamic hyperinflation of the lung, characteristic of COPD, in which the patients is unable to empty the lung completely before beginning the next breath, resulting in dyspnea.

Dr. Eves and colleagues enrolled 10 men with moderate to severe but clinically stable COPD, excluding patients dependent on supplemental oxygen, with cardiovascular disease, or musculoskeletal abnormalities.

The volunteers made three visits to the clinic, the first of which was designed to confirm the extent of COPD and the absence of cardiovascular contraindications to exercise.

On each subsequent visit, they underwent exercise testing with two of the four gases — air, hyperoxia, normoxic helium, and helium-hyperoxia — in a random order.

They were asked not to speak during the tests, in order to disguise the characteristic squeaky voice associated with breathing helium.

The exercise test consisted of constant-load cycling at 60% of the maximal work load, limited by the onset of symptoms such as shortness of breath or leg discomfort.

The researchers found:

Volunteers were able to exercise for 9.4 minutes on average while breathing air, compared with 17.8 minutes for hyperoxia and 16.7 minutes for normoxic helium.
By contrast, average exercise time with helium-hyperoxia was 26.3 minutes, significantly greater compared with air than with either hyperoxia or normoxic helium (at P=0.019 and P=0.007, respectively).
Exercise capacity on helium-hyperoxia improved by a factor of 2.45 compared with air, and by 56% and 92% when compared with hyperoxia and normoxic helium, respectively.
When the total work of breathing per minute was calculated, only helium-hyperoxia was significantly lower than with air, at P=0.008.

When breathing air, the researchers noted, shortness of breath was the main symptom that limited exercise. But when breathing helium-hyperoxia, the main symptom that prevented further exercise was leg discomfort.

That finding suggested that helium-hyperoxia “decreases the ventilatory constraints associated with COPD to an extent that skeletal muscle function becomes more of a limiting factor,” the researchers said.

The researchers said they had no potential conflicts.

Primary source: American Journal of Respiratory and Critical Care Medicine

Source reference:

Eves ND et al. “Helium-Hyperoxia, Exercise, and Respiratory Mechanics in Chronic Obstructive Pulmonary Disease.” Am J Respir Crit Care Med 2006;174:763-771.

SAN FRANCISCO, Jan. 20 — Chemotherapy-refractory pancreatic neuroendocrine tumors had durable responses and stable disease in patients treated with the mTOR inhibitor RAD001, an open-label study showed.

Median progression-free survival was 9.3 months in patients given RAD001 alone and 12.9 months in those who given the mTOR inhibitor along with octreotide (Sandostatin), James C. Yao, M.D., of the University of Texas M.D. Anderson Cancer Center, reported at the Gastrointestinal Cancers Symposium here.

The progression-free survival with RAD001 represented a two- to threefold increase compared with results from previous studies involving gefitinib (Iressa) and somatostatin analogs. Median overall survival has yet to be reached.

“The progression-free survival and overall survival support the efficacy of RAD001 in patients with chemotherapy-refractory pancreatic neuroendocrine tumors,” Dr. Yao concluded. “RAD001 was well tolerated and had a positive risk-benefit ratio.”

Steve Jobs, the Apple CEO, recently announced the need for a medical leave of absence because of apparent complications from treatment for a pancreatic neuroendocrine tumor. Jobs, however, was treated with surgery — a modified Whipple. (See: Steve Jobs Takes Medical Leave from Apple)

The new findings came from a study of 160 patients with advanced neuroendocrine tumors. Though slow growing, the tumors generally are incurable when they reach an advanced stage, said Dr. Yao. Median overall survival is about two years.

RAD001 is an oral agent that has demonstrated broad antitumor activity. Preliminary clinical evaluation in patients with neuroendocrine tumors showed “promising antitumor activity” when the agent was given in combination with octreotide, said Dr. Yao.

The 160-patient study included 115 patients who had not received octreotide in the 60 days prior to enrollment (stratum one) and 45 who had received the somatostatin analog for three months or longer (stratum two). All patients received RAD001 at a dose of 10 mg/d, and those patients on octreotide continued the drug.

The primary endpoint was overall response rate in stratum-one patients. Secondary endpoints included response rate in stratum two, response duration, safety, progression-free survival, and overall survival.

Dr. Yao reported that nine patients in stratum one had partial responses, resulting in a response rate of 7.8%. An additional 79 patients had stable disease. Combining patients who had objective responses and stable disease resulted in an overall clinical benefit of 76.5%.

In the second stratum, two patients had partial responses and 35 had stable disease, resulting in a total clinical benefit of 82.2%.

By central radiology review, patients in stratum one had a six-month PFS of 65.4%, nine-month PFS of 51.2%, and 12-month progression-free survival of 40.9%. Corresponding rates for stratum two were 70.6% at six and nine months and 58.9% at 12 months.

Stratum one had a 12-month survival of 74% and a 15-month survival of 52.6%. In stratum two, 90.3% of patients were alive at nine, 12, and 15 months.

A majority of patients had abnormal baseline levels of chromogranin A, which is generally considered to be a biomarker for neuroendocrine tumors, said Dr. Yao. Among patients who had at least a 30% decrease from baseline (responders), median progression-free survival was 13.3 months compared with 7.5 months for nonresponders (P=0.0004).

Adverse events were common, as headache, nausea, fatigue, diarrhea, rash, and stomatitis occurred in 20% or more of stratum one. However, grade 3-4 adverse events were uncommon, including only one grade 4 event (anemia).

Putting the results into context, Dr. Yao noted that in the previous studies of gefitinib and somatostatin analogs, no patient had an objective response, six-month progression-free survival was 28%, and median progression-free survival was four months.

The study was supported by Novartis.

One or more investigators in the study disclosed financial relationships with Novartis.

Primary source: Gastrointestinal Cancers Symposium

Source reference:
Yao JC, et al “A phase II trial of daily oral RAD001 (everolimus) in patients with metastatic pancreatic neuroendocrine tumors (NET) after failure of cytotoxic chemotherapy” ASCO GI 2009; Abstract 122.

Defects in a pathway with a misleading name may underlie some cases of schizophrenia, according to researchers conducting a genetic study.

Genomic variants known as microduplications in or near the gene for the vasoactive intestinal peptide (VIP) receptor were 14 times as common in a sample of patients with schizophrenia relative to normal controls, reported Jonathan Sebat, PhD, of the University of California San Diego, and colleagues, in the Feb. 24 issue of Nature.

VIP is actually a multifunctional protein that is produced throughout the body and is active in a host of body systems. In addition to playing multiple roles in the intestinal tract and circulatory systems, VIP helps regulate vaginal secretions, prolactin release, and circadian rhythms.

This last function is located in the brain, and previous studies have linked circadian rhythm disturbances with schizophrenia.

Sebat and colleagues did not set out to analyze the VIP pathway genome — that’s merely what was found from their genome-wide scan for copy number gains.

They undertook the study because earlier studies had identified copy number gains involving large DNA sequences (more than 500,000 bases) that were more common in schizophrenic patients, and wondered if replication of shorter sequences might also be linked to the disorder.

The researchers conducted the scans in a two-stage study. They first searched for copy number variants in 802 schizophrenia patients and 742 controls, which yielded positive findings in 114 genomic “regions of interest.”

In the second stage, Sebat and colleagues looked more closely at these regions in samples from 7,488 patients and 6,689 controls.

They found that microduplications within a 362-kilobase region at chromosomal location 7q36.3 — in or near the VIP receptor gene known as VIPR2 — were significantly more common in the patients, with an odds ratio of 14.1 (95% CI 3.5 to 123.9).

These were still rare — among all patients in both stages, only 29 had the microduplications at location 7q36.3 (0.35%). But this compared with just two individuals in the control groups (0.03%) with duplications there (P=5.7 x 10-7).

Despite low rate of copy number variations associated with the VIP receptor gene in the study, Sebat and colleagues suggested that the pathway could be worth pursuing as a diagnostic and therapeutic target.

“While duplications of VIPR2 account for a small percentage of patients, the rapidly growing list of rare copy number variants that are implicated in schizophrenia suggests that this psychiatric disorder is, in part, a constellation of multiple rare diseases,” the researchers wrote. “This knowledge, along with a growing interest in the development of drugs targeting rare disorders, provides an avenue for the development of new treatments for schizophrenia.”

Sebat and colleagues suggested that the precise pathological mechanism related to the variants involves cyclic adenosine monophosphate (cAMP) signaling. The cAMP molecule is important in a wide range of neural and cognitive functions.

To test the hypothesis, they took cell lines with and without sequence duplications or triplications in the 7q36.3 region and treated them with agents that stimulate the VIP pathway. Higher cAMP accumulation was seen in the cells with the multiple sequence copies, supporting the researchers’ hunch.

The study was funded by the National Institutes of Health and individual and foundation grants to the authors.

The authors declared they had no relevant financial interests.

SAN ANTONIO, Dec. 12 — Breast tumors that develop resistance to aromatase inhibitors may reacquire sensitivity with low-dose estradiol, according to a small study reported here.

About 30% of a small group with an aromatase inhibitor-resistant-malignancy developed stable disease or better responses with low-dose estradiol, found Matthew Ellis, MB, Ph.D., of Washington University in St. Louis.

Several patients then responded to retreatment with an aromatase inhibitor, Dr. Ellis said at the San Antonio Breast Cancer Symposium.

Calling the retreatment findings “the most exciting aspect of this work,” Dr. Ellis nonetheless cautioned that “retreatment obviously is the next area we need to [address], along with mechanistic studies to try to understand the paradoxes of this therapy.”

For more than 60 years, clinicians and researchers have puzzled over estrogen’s seemingly paradoxical effects on cell biology, which can be growth promoting in some circumstances and growth inhibiting in others. Dr. Ellis reported findings from one of the first controlled clinical trials designed to test whether estrogen might have therapeutic potential in advanced breast cancer.

His study involved patients with metastatic, hormone-receptor-positive breast tumors that had acquired resistance to aromatase inhibitors during therapy. Thirty-two patients were randomized to estradiol at 30 mg (10 mg tid) and 34 to 6 mg (2 mg tid).

Treatment continued until disease progression. Patients who had stable disease or better responses had the option to resume treatment with an aromatase inhibitor.

The primary objective was total clinical benefit (complete and partial responses plus stable disease). Secondary objectives included comparisons of progression-free survival, time to treatment failure, and overall survival; quality of life; frequency of response to retreatment with an aromatase inhibitor; change in insulin-like growth factor 1 (IGF-1); and association (if any) between changes in PET tracer uptake and response to therapy.

The two arms differed substantially in toxicity. The low dose of estradiol caused minimal side effects, whereas the high dose was associated with more nausea and vomiting, hyponatremia, and pleural effusion. Dr. Ellis reported that 21 (66%) patients in the high-dose arm had no serious adverse effects versus 30 (88%) in the low-dose arm (P=0.02).

High-dose estradiol led to one partial response, and eight patients had stable disease, resulting in a total clinical benefit of 28%. In the low-dose arm three patients had partial responses and seven had stable disease, for a total clinical benefit of 29%.

The groups did not differ significantly in progression-free survival, time to treatment failure, or in overall survival.

“Both groups had quite consistent disease control on estradiol therapy,” said Dr. Ellis. “Time to treatment failure trended toward being worse in the 30-mg arm, because of early discontinuation due to side effects.”

Tumor uptake of estrogen, as assessed by PET FDG imaging, proved to be a strong predictor of treatment response. PET flare, defined as a 12% increase in standard uptake values, occurred in all patients who had partial responses and in nine of 13 who had stable disease. In contrast, only three patients with progressive disease had PET flare (P

RICHMOND, Va., Jan. 14 — Patients with sickle cell disease endure pain that is more frequent and more severe than commonly appreciated by clinicians, investigators here found.

In a study of 232 patients ages 16 and older, recruited throughout Virginia, more than half the patients reported having pain more than half the time, Wally R. Smith, M.D., of Virginia Commonwealth University, and colleagues reported in the Jan. 15 issue of Annals of Internal Medicine.

Almost 30% of the patients said they were in pain virtually every day, the survey found.

Yet most pain days did not correlate with sickle cell crises or health care utilization, a traditional proxy for pain and underlying vascular occlusion.

“Our findings suggest a vast, mostly submerged iceberg of sickle cell pain that is not seen by most professionals, but rather is managed outside of medical facilities,” the authors stated. “The extremely low proportion of sickle cell disease pain that is managed within medical facilities explains why treating physicians might believe that sickle cell pain is the exception rather than the rule.”

Patients with sickle cell disease may have severe and disabling pain that typically occurs in the long bones, joints, back, abdomen, and chest, the authors said. Vaso-occlusive pain accounts for most medical contacts with sickle cell patients. The frequently episodic nature of contacts may lead to the conclusion that patients do not have pain on most days.

Caregivers traditionally have used the term “crisis” to describe sickle cell patients’ medical contacts and have used the term chronic pain syndrome to describe pain associated with sickle cell disease complications, such as ankle ulcers or avascular necrosis. However, the relationship among sickle disease pain, crises, and health care utilization had not been examined in a large-scale longitudinal epidemiologic study, according to the authors.

In the Pain in Sickle Cell Epidemiology Study (PiSCES), patients completed daily diaries for as long as six months, recording maximum pain (on a scale of 0-9), crises, and use of hospital, emergency, or unscheduled ambulatory care for pain.

Overall, 54.5% of patients reported pain on more than half (?‰?51%) of 31,017 patient-days. On 38.3% of days, patients described their pain as being at less than crisis level and not requiring unplanned health care utilization. They reported crisis-level pain on 12.7% of days, but managed the pain at home. The patients reported unplanned health care utilization on 3.5% of days. Inclusion of scheduled visits increased utilization to only 5.1% of days.

The investigators found that 29.3% of participants reported having pain on more than 95% of diary days, whereas 14.2% reported pain on no more than 5% of diary days.

Home opiate use independently predicted pain, crises, and utilization. Mean pain intensity increased with the percentage of pain days (P

LITTLE FALLS, N.J., July 30 — When it comes to nutrition, there’s no difference whether patients consume organic or conventionally produced foods, researchers say.

A review of more than 50 studies found no difference in nutrient content — including vitamin C, calcium, potassium, and zinc — between the types of food, Alan Dangour, PhD, of the London School of Hygiene & Topical Medicine, and colleagues reported.

The study appears in the September 2009 issue of the American Journal of Clinical Nutrition.

Marion Nestle, PhD, MPH, an expert on nutrition and food studies at New York University, disputed the scope of the findings.

“Plenty of studies have shown organics to have higher levels of nutrients,” she said. “Nutrient levels ought to be higher in plants grown on better soils.”

The “organic” label is reserved for farms that limit pesticide and herbicide use in crops and drug use in livestock.

Organic foods are typically more expensive, but sales have been booming because of the perception that they’re healthier than conventionally produced foods.

So, to determine whether there is a difference in nutritional benefits, the researchers conducted a review of 55 studies published between Jan. 1, 1958 and Feb. 29, 2008.

They evaluated foods’ nutrient content, including vitamin C, phenolic compounds, magnesium, potassium, calcium, zinc, copper, and total soluble solids.

They found no evidence of a difference between organic and conventional crops in terms of eight of those nutrient categories.

Conventional crops contained more nitrogen, while organics had more phosphorus and greater acidity.

The researchers said the differences were likely due to differences in fertilizer use and ripeness of fruits and vegetables at harvest.

But they said it’s “unlikely that consumption of these nutrients at the levels reported in organic foods in this study provide any health benefit.”

Nor did the researchers find nutritional differences with regard to animal-source foods — although they noted that there were far fewer studies on these foods compared with produce. That made analysis was more limited, they said.

Also, the researchers did not include an analysis of contaminants or chemical residues used in the food products.

Chemical fertilizer, herbicides, and pesticides may also affect the chemical content of foods, they said, and the organic foods may have an advantage because of their controlled use of chemicals and medicines. That warrants further study, the researchers said.

Niyati Parekh, PhD, professor of nutrition at New York University who was not involved in the study, said the findings regarding nutritional content are not surprising. The larger concern with organic versus nonorganic foods is chemical content.

“The person who spends the extra $5 to buy organic is not doing it for the nutrients,” Dr. Parekh said. “They’re concerned with the chemicals.”

She said there is not a large body of literature on the chemical content of organic versus nonorganic food because organic labeling is still a “gray area.”

“No one has defined what organic is,” Dr. Parekh said. “Until we do that, it’s hard to study.”

Maria Romano, MS, RD, clinical nutritionist for adult oncology at Montefiore Medical Center in New York, said that even though they’re difficult to design and execute, studies comparing organic and nonorganic products are important.

“We know pesticides pose a risk to human health even in small doses, or those considered safe by industry,” she said. “They can have toxic effects and in the long term can contribute to cancer.”

Meanwhile, Dr. Nestle emphasized that “organics aren’t about nutrients. They are about cleaner and more sustainable production methods,” including “lower levels of pesticides and herbicides, which seems like a good idea.”

The authors noted the possibility of reporting bias, which is a potential limitation of systematic reviews.

The study was supported by the UK Food Standards Agency.

The researchers reported no conflicts of interest.

Primary source: American Journal of Clinical Nutrition

Source reference:

Dangour AD, et al “Nutritional quality of organic foods: A systematic review” Am J Clin Nutr 2009; DOI: 10.3945/ajcn.2009.28041.

STANFORD, Calif., Sept. 15 — Half of the Asian women who carry BRCA1/2 cancer mutations may fall through the statistical cracks of two widely used prediction models, investigators here concluded.

Both the BRCAPRO and Myriad II programs predicted 50% fewer Asian carriers than were actually observed, Allison W. Kurian, M.D., of Stanford, and colleagues reported online in the Journal of Clinical Oncology.

In contrast, both programs’ predictions for white mutation carriers were virtually identical to the observed number of carriers.

“Both models’ two-fold underprediction of the total number of Asian BRCA1/2 mutation carriers argues for caution in their use to guide clinical testing in patients of Asian descent,” the authors concluded.

Breast cancer epidemiology differs between Asian and white populations, but knowledge about hereditary breast cancer in Asians is lacking, the researchers said.

More Asians are being tested for BRCA1/2 mutations, they continued, but the predictive accuracy of models used to guide testing had not been determined in Asians.

To evaluate the BRCAPRO and Myriad II models, the investigators recruited 200 Asian women and a control group of white women. All participants underwent testing for BRCA1/2 mutations at four cancer genetics clinics.

In the white control population, genetic testing identified 25 mutation carriers. The BRCAPRO model predicted 24, and the Myriad II predicted 25.

Genetic testing identified 49 mutation carriers in the Asian participants. However, BRCAPRO predicted only 25, and Myriad II predicted 26.

The ethnic difference with BRCAPRO reflected substantial underestimation of BRCA2 in the Asian participants, as testing identified 26 carriers but the model predicted only four. Separate mutation predictions were not available for Myriad II.

Comparison of area under the receiver operating characteristic curves for both models revealed a trend toward lower curves in the Asian participants compared with the white participants, suggesting less accurate discrimination between carriers and noncarriers in the Asian group.

The two prediction models are available as part of a free software package that can be downloaded from the Internet, the authors noted. Additionally, the models are updated regularly.

“Given their availability and their generally superior performance on validation, BRCAPRO and Myriad II are by far the most widely used models to guide BRCA1/2 mutation testing in the United States,” the authors said. “Consequently, their performance in Asian-Americans has high clinical relevance, which guided our selection of these two models for the study.”

The study was supported by the Susan G. Komen Breast Cancer Research Foundation. The authors reported no potential conflicts of interest.

Primary source: Journal of Clinical Oncology

Source reference:

Kurian AW, et al “Performance of BRCA1/2 mutation prediction models in Asian Americans” J Clin Oncol 2008; 26: DOI: 10.1200/JCO.2008.16.8310.