GENEVA — Repeat scuba dives appear to harm the endothelium, particularly when breathing the mix of gases popular with recreational divers, according to a small study.
With the low-nitrogen air mix called nitrox, endothelial function as measured by flow mediated dilation dropped significantly after each dive — and didn’t fully recover between dives, Emeline Van Craenenbroeck, MD, PhD, of Antwerp University Hospital in Antwerp, Belgium, and colleagues reported.
Endothelial repair mechanisms appeared activated as well in their study of 10 divers, presented here at the European Society of Cardiology’s EuroPRevent meeting.

Based on the results of this small study, Van Craenenbroeck told MedPage Today that in his opinion the use of regular compressed air was safer for vessels.

Nitrox is popular because its lower nitrogen content allows divers to stay down longer and return to the surface faster with less decompression time needed, she explained.

But in the study, each dive with standard air reduced endothelial function by roughly 2 percentage points from around 5% flow mediated dilation at baseline (P=NS), whereas it dropped roughly 4 percentage points on the initial dive with nitrox and then, without returning to baseline, fell more than 2 percentage points on a subsequent dive two days later (both P<0.05).

“We already knew diving was bad for the endothelium,” Van Craenenbroeck told MedPage Today, noting that one prior study suggested that endothelial function didn’t return to baseline more than six days after just a single dive.

What effect these repeated dings to blood vessels function and repair mechanisms for frequent divers, such as military and professional divers, have on cardiovascular outcomes isn’t known.

“There’s no data on it,” Van Craenenbroeck cautioned.

But she noted that it might be expected to lead to more atherosclerosis and coronary artery disease.

Still, divers have a choice in the gas mix they use and could attempt to protect their vessels by a preconditioning jog before going down into the water, since this method boosts oxygenation in soccer players and stimulates endothelial progenitor cells in healthy individuals, she suggested.

Her group studied a group of 10 experienced military divers who dove in the open sea with regular compressed air once a day for three days with measurements immediately before and after the dives on day one and three, and then repeated the experiment with nitrox after 15 days of rest.

All the dives were to a depth of 18 m (59 feet) with 47 minutes spent at the bottom. No cases of decompression sickness occurred.

The acute effect of a single dive pooled across the 36 dives was a decrease in endothelial progenitor cells (which differentiate into endothelial cells) circulating in the peripheral blood and an increase in circulating angiogenic cells (which contribute to re-endothelialization by stimulating mature endothelial cells to proliferate).

Together, the two factors seem to indicate an uptick in endothelial repair, the researchers suggested.

But the effects were significant only with nitrox use, they noted.

“Diving with nitrox generates less bubbles during decompression, but elicits more hyperoxia,” she told attendees. “We know that the hyperoxia during diving elicits oxidative stress and subsequent endothelial dysfunction.”

Van Craenenbroeck reported having no conflicts of interest to disclose.

WASHINGTON, June 27 — Medicare payments will be cut by 10.6% for physicians as of July 1, the upshot of an 11th-hour rescue effort that was blocked by Senate Republicans.

In an unusually blunt condemnation of an action by the GOP, AMA president Nancy H. Nielsen, M.D., a Buffalo, N.Y., internist, accused the Senate Republicans of following the “direction of the Bush administration” by voting to “protect health insurance companies at the expense of America’s seniors, disabled, and military families.”

The Bush administration opposed the Medicare fix, approved by the House in a vote of 355 to 59, which would have barred the pay cut. The Senate needed 60 votes to make the bill filibuster-proof, but could only muster 59.

“Today, thanks to some senators, we stand at the brink of a Medicare meltdown,” she said.

The AMA’s comment was echoed by Rep. John D. Dingell (D-Mich.), chairman of the House Energy and Commerce Committee, who commented that “Republican senators were wrong to block legislation that helps beneficiaries and doctors so that they could protect payments to the insurance companies that are scamming our seniors.”

Dingell said the overwhelming bipartisan vote in the House had represented “an effort to improve Medicare’s preventive and mental health benefits, help low-income beneficiaries and rural communities, and ensure that seniors and disabled Americans can continue to see the doctors they know and trust.”

He added, “It’s unfortunate that Senate Republicans have joined the administration in looking out for insurance industry profits instead of patients. I urge Senate Republicans to reconsider their misguided position.”

The AMA has long argued that physicians would respond to any cut in physician reimbursements by limiting the number of the Medicare patients they accept in their practices.

Over the past decade that argument has resonated with Congress, as, year after year, it took last-minute action to block automatic cutbacks in physician payment dictated by the program’s formula.

That’s what happened in December, but the legislation carried the reprieve only until July 1. And this week, there was no agreement on a fix.

So the cut will take place as scheduled, because the senators will be leaving tonight for the Fourth of July break.

An AMA spokesperson said the group would be pressing for relief when Congress returns in about 10 days, but meanwhile the fee cut will affect billings as of July 1.

Asked whether there could be a retrospective fix, the spokesperson did not know.

“The Senate must return from their recess and make seniors’ health care their top priority,” said Dr. Nielsen. “For doctors, this is not a partisan issue — it’s a patient- access issue.”

Having a medical home was associated with improved healthcare utilization among a large, nationally representative sample of children without special medical needs, researchers found.

Children who received care in a medical home were more likely to have had a preventive care visit within the previous year, with an adjusted odds ratio of 1.32 (95% CI 1.22 to 1.43, P<0.05), according to Webb E. Long, MD, and colleagues from Boston University.

They also were less likely to have outpatient visits because of illness (OR 0.71, 95% CI 0.66 to 0.76) and visits to the emergency department (OR 0.70, 95% CI 0.65 to 0.76, P<0.05 for both), the researchers reported online in Pediatrics.

The American Academy of Pediatrics advocates the medical home model, described as “accessible, family-centered, continuous, comprehensive, coordinated, compassionate, and culturally effective,” as the principal source of healthcare for all U.S. children.

The medical home was initially implemented for children with special healthcare needs and showed improved outcomes such as reducing hospitalizations.

To see if the wider pediatric population could benefit as well, Long and colleagues did a secondary analysis of data from the 2003 National Survey of Children’s Health.

Among the 70,007 children without special healthcare needs in the study sample, 58.1% had a medical home.

Children with medical homes were more likely to be white and younger; to speak English; live with two parents; to have parents with at least a high-school education; and to have health insurance.

They were more likely to be rated by their parents as having excellent or very good health (OR 1.29, 95% CI 1.15 to 1.45) rather than good, fair, or poor health.

Behaviors that are considered health-promoting also were more common in children with a medical home: Being read to daily, OR 1.46, 95% CI 1.13 to 1.89 (P<0.05) Having sufficient sleep each day, OR 1.56, 95% CI 1.20 to 2.04 (P<0.05) Always wearing a helmet when appropriate, OR 1.18, 95% CI 1.03 to 1.34 (P<0.05) Having less than two hours screen time daily, OR 1.12, 95% CI 1.02 to 1.22 (P<0.05)

When the researchers looked at the data according to age, they found that children younger than one year had a strong association between having a medical home and having had preventive care (OR 1.67, 95% CI 1.08 to 2.57, P<0.05).

Children in this youngest age group who had medical homes also had strong associations with having global health ratings of excellent or very good (OR 1.44, 95% CI 1.02 to 2.04, P<0.05).

For children ages six to 11, the association with the medical home was strongest for having fewer visits to the emergency department (OR 0.64, 95% CI 0.55 to 0.74, P<0.05).

And for adolescents, the association was strongest for having fewer outpatient visits (OR 0.67, 95% CI 0.59 to 0.75, P<0.05).

“The AAP has long promoted the medical home for all children, and the Affordable Care Act of 2009 promotes the patient-centered medical home; this study provides further evidence supporting these policies,” Long and colleagues wrote.

Wide use of the medical home model should result in substantial cost reductions, such as cutting down on expensive emergency department visits, and should broaden access to healthcare for the underserved.

Limitations of the study were lack of validation of the definition of medical home, absence of data on continuity of care, cross-sectional design, and parental reporting of data. Also, unmeasured variables may have exerted an influence, although the results were adjusted to account for racial and socioeconomic disparities.

The authors reported no financial disclosures.

ABERDEEN, Scotland, May 5 ??” Excess folate was associated with an increased rate of twin births after in-vitro transfer of two embryos, researchers here reported.

With the British considering a proposal to fortify flour with folic acid, a study in the May 6 issue of The Lancet illustrated the added effect folate fortification might have on twin births after fertilization with more than one embryo.

Fortification of flour with folic acid in the U.S. in 1998 was linked to an 11% to 13% increase in the rate of multiple gestations after fertility treatment, and similar results could be expected in the Britain, according to Paul Haggarty, M.D., of Aberdeen University here and colleagues.

Dr. Haggerty and colleagues emphasized that the need to increase the intake of folic acid to reduce the rate of neural-tube defects is not in doubt, but the associated risk of multiple births after IVF needs to be addressed.

In a prospective cohort study of 602 women undergoing fertility treatment at the Aberdeen Reproduction Unit, the likelihood of twin births rose with increased concentrations of plasma folate (1.52, 1.01-2.28 P=0.032) and red-cell folate (1.28, 1.00-1.65; P=0.039).

However, high folate status did not increase the chance of a successful pregnancy after IVF, the researchers said, and folate supplementation did not increase twinning in a separate cohort of women who became pregnant naturally.

Of the women who recorded their supplement use, 73% (374) took the recommended dose of folic acid (400 ??g daily); of the rest, 9% (44) took less, and of these 3% (15) did not take any.

On the other hand, 19% (95) took more than the recommended amount and 3% of these (14) exceeded 1 mg daily, the researchers reported.

Folate and vitamin B12 intake were assessed with a questionnaire, while plasma and red-blood-cell concentrations were measured by radioimmunoassay.

The plasma-derived folate intake produced an odds ratio for twin births of 1.27 for a 100 ??g per day change in the intake of folate. This is similar to the odds ratio of 1.22 noted for the directly measured folate intake, the researchers noted.

High levels of vitamin B12 in the plasma were also related to the likelihood of twin birth, although this finding might be a secondary effect, the authors stated. The likelihood of a twin birth was also related to younger age, they wrote.

In an attempt to assess genetic factors that might influence the success of in-vitro fertilization, the investigators also measured six B-vitamin-related gene variants in the women given IVF treatment and in 932 women who conceived naturally.

Women who were homozygous for the 1298 CC variant of methylenetetrahydrofolate reductase (MTHFR), rather than the AA variant, were less likely to have a live birth after IVF (0.24, 0.08-0.71; P=0.003 or to have had a previous pregnancy (0.42, 0.21-0.81; P=0.008), the researchers reported.

This finding suggested, Dr. Haggarty said, that the MTHFR genotype is linked to a woman’s potential to produce healthy embryos, possibly through interaction with genes related to DNA methylation. The AA genotype may be able to overcome the genetic factors that predispose to infertility.

The researchers hypothesized that a genotype that increases the likelihood of conception after IVF is more likely to be passed on to the offspring. Fertility is thought to be heritable, but the identification of even one genetic variant linked to IVF outcome raises the prospect that reproductive technologies could alter the usual selection pressures.

“The genetic and epigenetic consequences of reproductive technologies should, therefore, be carefully monitored,” Dr. Haggarty and colleagues said.

They added, “Our results suggest that the high incidence of twin births could be reduced, while maintaining live birth rates, by encouraging women not to exceed recommended doses of folic acid and by identifying those at high risk of twins after double embryo transfer on the basis of their plasma folate concentrations and age,” Dr. Haggerty wrote.

In an editorial in the same Lancet issue, Gary Steinman, M.D., of Long Island Jewish Medical Center in New York, wrote that multiple gestations arise in as many as one-third of women having in-vitro fertilization. However, he said, the Haggarty study did not find an underlying mechanism to explain this trend.

One possible mechanism, he said, involves the role of calcium-dependent uvomorulin (E-cadherin) in intercellular bonding of embryo blastomeres. In a low-calcium environment, he wrote, blastomeres detach from one another, increasing the likelihood of a multiple pregnancy. “Indeed,” he wrote, “the addition of edetic acid (a calcium chelator) to the incubation media used in IVF increases the chances of monozygotic multifetal pregnancies.”

In a broader discussion of the effect of diet on twinning around the world, Dr. Steinman mentioned the role of insulin-like growth factor (IGF) in various foods such as milk or yams. IGF, he noted, enhances ovarian follicle recruitment in twinning and decreases ovum apoptosis.

Understanding nutritional factors that can affect reproductive physiology may improve gestational outcomes, he concluded.

Primary source: The Lancet

Source reference:
Paul Haggarty, et al “Effect of B vitamins and genetics on success of in-vitro fertilization: prospective cohort study,” The Lancet 2006; 367: 1513-1519.

Additional source: The Lancet

Source reference:
Gary Steinman, “Can the chance of having twins be modified by diet?” The Lancet 2006; 367: 1461-1462.

Obstructive sleep apnea may be the underlying cause of awakening and urination in men with enlarged prostates, a new study suggests.

The study included men aged 55 to 75 who were diagnosed with benign prostate enlargement (BPE) and reported nighttime urination (nocturia) at least once nightly. They were compared to a control group of same-age men who had no BPE and one or no nocturia episodes per night.

The Israeli researchers found that 57.8 percent of the men with BPE may have obstructive sleep apnea and that the sleep disorder may be the actual cause of the sleep awakenings the men believe are caused by the need to urinate. Obstructive sleep apnea is characterized by snoring, pauses in a person’s breathing that cause awakenings, and also daytime sleepiness.

The study, by the team at Ben-Gurion University of the Negev, is published in the March/April issue of the Journal of the American Board of Family Medicine.

“If nocturia severity in BPE patients is actually a pre-existing sleep disorder, this can now be treated and help improve patients’ quality of life,” Dr. Howard Tandeter, a researcher in the family medicine department, said in a university news release.

If patients with BPE report frequent nighttime awakenings to urinate, doctors should suspect obstructive sleep apnea as a possible cause and treat accordingly, Tandeter recommended.

“Even among those patients with well-defined medical reasons for nocturia, sleep disorders may still be found as the source of most awakenings,” he said. “Therefore, the diagnosis of a sleep disorder should be seriously considered whenever a patient reports frequent awakenings from sleep to urinate since the problem is treatable.”

More information

The U.S. National Institute of Diabetes and Digestive and Kidney Diseases has more about enlarged prostate.

VANCOUVER — A deadly fungal infection that surprised researchers by popping up in a nontropical climate is spreading across the Pacific Northwest.

In a pair of reports presented at the annual meeting of the Infectious Diseases Society of America, researchers said that Cryptococcus gattii was first identified on Vancouver Island, then in British Columbia — and has now emerged in the U.S. as well.

Researchers reported 263 C. gattii infections since 1999 in British Columbia and 70 infections in the U.S. since 2004.

“C. gattii is an emerging and serious infection in the Pacific Northwest,” said Julie Harris, PhD, MPH, a staff epidemiologist at the CDC who discussed the fungal disease during a press briefing.

Human infections with C. gattii were first reported on Vancouver Island where the province capital of Victoria is located and then in British Columbia where the city of Vancouver is located. Since being reported in the U.S., infections with C. gattii have been found in Washington, Oregon, Idaho, and California.

Since its first emergence in British Columbia, about 24 cases of C. gattii infections are reported each year. About 9% of patients infected with the fungus have died, said Eleni Galanis, MD, MPH, a physician-epidemiologist at the British Columbia Centre for Disease Control in Vancouver.

In the U.S., the CDC’s Harris said the fatality rate for C. gattii cases is about 32%. She said doctors are not sure why the fatality rate is higher in the U.S. compared with Canada, but underlying conditions of the infected patients may play a role in the higher U.S. death rate.

While nontropical C. gattii exposure appears to be limited to the Pacific Northwest, the fungus shows up throughout the environment in the affected area. C. gattii is believed to prefer rotting wood or hollow of trees. Galanis told MedPage Today that researchers believe the fungus will remain localized in that general area.

“This study emphasized the importance of physicians taking a travel history when evaluating their patients,” said James Hughes, MD, professor of medicine and public health at Emory University, Atlanta, and president-elect of the IDSA. Hughes moderated the press briefing.

Galanis said that C. gattii was believed to be endemic to tropical areas, affecting only subtropical parts of Australia and South America, until it appeared in patients in British Columbia.

“The reasons why it emerged and where it came from are still unclear,” she said.

“People get infected by breathing in the fungus and usually get an infection in the lungs, presenting as pneumonia or lung nodules,” Galanis explained. “Symptoms include cough, shortness of breath, and fever. The infection can spread beyond the lungs and enter the central nervous system or the brain where it can cause meningitis, and these patients present with headache and fever,” she added.

“A large percentage — 40% of those infected — are immunocompromised by either HIV infection, cancer, organ transplant, or have been on corticosteroid therapy. People also at risk of C. gattii infection include people over the age of 50, people with chronic lung diseases, and people who smoke,” she said.

Harris said that most of the 70 infections in the U.S have occurred in Washington and Oregon. “The number of infections in the U.S. is still increasing,” she said. Cases have also been found in Idaho, California, Alaska, Hawaii, and Arizona. Harris said the Alaska and Idaho cases are likely travel-associated.

“Treatment for C. gattii is lengthy, lasting six to 18 months and involves use of amphotericin and fluconazole,” Harris told MedPage Today. “About one-third of the patients develop fungal masses in the lungs or brain which can make the disease more difficult to treat.

About 90% of the patients have been hospitalized for their infections. Having an underlying medical problem appears to be a risk factor. Although 75% of the patients have an underlying health problem, 25% of the infected patients were healthy before encountering the fungus, Harris said.

“The patients who were previously healthy appear to have a more serious disease than those who had an underlying disease when infected. It should be noted that these infections are still rare,” she added.

Galanis disclosed financial relationships with Astellas Pharma Canada and Pfizer Canada.

Harris and co-authors had no disclosures.

WASHINGTON, Sept. 21-Three out of every four men wash their hands after a trip to a public restroom, but the rest seem to be incorrigible, microbiologists reported today. Fewer women fall into that category.

Overall, 82% of more than 6,300 men and women observed leaving restrooms washed their hands in 2005 compared with 78% in 2003, said the American Society of Microbiology and the Soap and Detergent Association.

But women accounted for nearly all of that improvement, the groups said, from 83% to 90%.

Men, however, remained the great unwashed, with a negligible soap-and-water improvement to 75% in 2005 from 74% in 2003.

The groups also reported in a separate survey a suggestion that neither men nor women are all that truthful about their bathroom hygiene. When asked in a telephone survey whether they washed their hands after using a public restroom, 91% said yes, a contrast with the observational survey’s finding of 82%.

“Our message is clear: One of the most effective tools in preventing the spread of infection is literally at our fingertips,” said Judy Daly, Ph.D., the ASM’s secretary and a professor of pathology at the University of Utah School of Medicine in Salt Lake City. “Just 20 seconds of water, soap and rubbing can really cause an extremely wonderful intervention,” said Dr. Daly, who presented the survey findings at a press conference here.

In the telephone survey, 1,013 American adults were questioned in August 2005 about their hand-hygiene habits, including using public restrooms and hand-washing at home. Among the survey’s findings:

91% said they washed their hands after using a public restroom.
83% said they washed after using the bathroom at home.
77% said they washed before handling or eating food.
73% said they washed after changing a dirty diaper.
42% said they washed after petting a dog or cat.
21% said they washed after handling money.
32% said they washed after coughing and sneezing, a figure that concerned researchers.

Hand-washing after coughing and sneezing could reduce the spread of infection, including respiratory diseases, Dr. Daly said. “For two hours, many things can stay alive on the hands. The drier the environment, the more likely the organisms are going to die.”

The telephone interview also found younger adults more likely to wash especially when it came to petting animals, coughing and sneezing, using a public restroom or changing a diaper. Older adults were better at wash-up after handling money and food, or using the bathroom at home.

In the observational survey, the investigators watched 6,336 men and women at six public bathrooms in four major cities. The sites included Atlanta’s Turner Field, Chicago’s Museum of Science and Industry and the Shedd Aquarium, New York’s Penn and Grand Central train stations, and San Francisco’s Ferry Terminal Farmers Market. The researchers were asked to rotate the public bathrooms they studied so they didn’t double-count someone.

Among the findings:

Sports fans, especially men, scored with some of the dirtiest hands; overall, 26% of those observed at Atlanta’s Turner Field did not wash. Sixteen percent of the women and 37% of the men did not wash.
The biggest disparities between men and women were observed in New York’s Penn Station. Ninety-two percent of the women washed their hands compared with only 64% of the men.
San Franciscans appeared to have the best hand hygiene habits. Overall, 88% of those observed at the Ferry Terminal Farmers Market washed — 85% of the men and 91% of the women washed their hands.

The findings show that public health experts need to emphasize the importance of hand washing even more often, especially with men, Dr. Daly said.

The researchers pointed out that there has been no evidence to indicate that the popularity of antibacterial household items such as soap and cleaning products have contributed to antibiotic resistance.

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ROME — Even with treatment, women with rheumatoid arthritis (RA) still feel its negative effects on their lives and seek new sources of relief from pain and disability, a researcher said here.

A computer-based survey of nearly 2,000 women with rheumatoid arthritis in seven affluent Western countries found that 63% reported “pain on a daily basis,” according to Vibeke Strand, MD, of Stanford University in Palo Alto, Calif.

And 49% said they wanted additional ways to obtain relief beyond medications they were already taking.

The latter finding “was very much an eye-opener to me,” Strand told attendees at the European League Against Rheumatism meeting.

She added that, although biologic drugs had clearly made RA treatment more effective, “they are not doing as good a job as we’d like to think they could do.”

The survey was carried out in August 2009 and was made available to more than 27,000 women participating in an online research panel; 1,958 completed the questionnaire.

Their mean age was 46 and three-quarters had been diagnosed with RA at least one year before.

Countries represented were the U.S., Canada, France, Italy, Germany, Spain, and Great Britain, with some 300 individuals from each nation except Canada, which contributed 155.

Respondents were asked to rate the impact of arthritis-related pain and disability on their ability to work and manage activities of daily living, to engage in hobbies, social activities, and intimate relationships.

The researchers found that: 87% of respondents regularly discussed ongoing pain with their healthcare providers 49% found at least some activities more difficult or impossible to do 23% had stopped working because of the disease 71% of those still working said they were less productive at work 24% reported difficulty sleeping 56% said their disease was emotionally distressing 40% reported feeling depressed much of the time 40% of single respondents said the disease made it more difficult to find a partner 22% of separated or divorced respondents said the disease played a role in the failure of the relationship

Strand noted that many of these effects are interrelated. For example, she said, sleep difficulties lead to increased fatigue, which in turn lowers pain thresholds.

She cautioned that the survey had several important limitations, including the potential for recruitment bias, the small sample size, and reliance on participants’ report of the RA diagnosis.

On the other hand, Strand said, the findings were consistent across respondents from all the countries included in the sample. She added that similar results were scheduled to be presented here later in the meeting from a separate survey in Germany.

All in all, she said, “this has touched the tip of a very large iceberg.”

Session co-moderator David Magnusson, vice chairman of the Swedish Rheumatism Association, commented that the findings weren’t surprising.

“But I think it’s important for this to get out because people don’t think like that,” he said.

Magnusson, who was not involved with the research, agreed that the potential for recruitment bias in the survey was real — that patients with poorer symptom control might have been more inclined to participate than those whose treatment was more successful.

But he added that many patients also under-report the severity of symptoms.

On balance, Magnusson said, the findings reported by Strand probably reflect the average of patient experience fairly well.

“The research highlights the complexity of the management of RA, and the pain associated with RA, over and above basic symptom control,” said Paul Emery, MD, president of EULAR and a rheumatologist at the University of Leeds in Britain, in a EULAR press release.

It is “of huge importance” to reduce pain, improve work productivity, and manage the social impact in patients with the disease, added Emery, who was a co-author of the study.

UCB Pharma supported the study.

Strand reported relationships with Abbott Immunology, Alder, Almirall, Amgen Corporation, AstraZeneca, BiogenIdec, CanFite, Centocor, Chelsea, Crescendo, Cypress Biosciences, Eurodiagnostica, Fibrogen, Forest Laboratories, Genentech, Human Genome Sciences, Idera, Incyte, Jazz Pharmaceuticals, Lexicon Genetics, Logical Therapeutics, Lux Biosciences, Novartis Pharmaceuticals, NovoNordisk, Nuon, Ono Pharmaceuticals, Pfizer, Rigel, Roche, sanofi-aventis, Savient, Schering-Plough, SKK, and UCB.

Emery reported relationships with UCB.

Magnusson reported no conflicts of interest.

DENVER — Aminophylline is safe and feasible with the newer generation vasodilator regadenoson (Lexiscan) in patients undergoing myocardial perfusion imaging (MPI), a new study demonstrated.
Aminophylline is a bronchodilator often used with adenosine and dipyridamole to blunt gastrointestinal side effects during stress perfusion imaging,
Compared with placebo, intravenous aminophylline significantly reduced the primary endpoint of diarrhea or abdominal discomfort (17.7% versus 8.9%, P=0.04), Raysa Morales Demori, MD, from Rush University Medical Center in Chicago, and colleagues reported.

The aminophylline group also had significantly less diarrhea than the placebo group (3.2% versus 10.5%, P=0.02), according to the group’s work presented here at the American Society of Nuclear Cardiology meeting.

Regadenoson, a selective A2a adenosine receptor agonist, has gained widespread use since its FDA approval in 2008 “owing to its simple use,” which includes administration in a single bolus and the same dose for everybody rather than a weight-based dose, Morales said.

In the ADVANCE-MPI trial, regadenoson, compared with adenosine, was associated with fewer side effects of flushing, dyspnea, and chest pain but more frequent adverse effects of headache, dizziness, and abdominal discomfort, Morales said.

She noted that the ADVANCE-MPI trial did not separate out diarrhea and since regadenoson’s approval, “there has been increased appreciation of diarrhea and fecal incontinence as a side effect, which occasionally occurs during the stress-SPECT acquisition.”

A survey at Rush University of 100 consecutive regadenoson-stress myocardial perfusion imaging patients found that 22% had abdominal discomfort and 3% reported diarrhea (all of whom also had abdominal discomfort).

The “strong association” between diarrhea and abdominal discomfort “suggested to us that abdominal discomfort is a surrogate or precursor of diarrhea,” Morales said.

Intravenous aminophylline has been used to attenuate the side effects of adenosine and dipyridamole, but whether its routine administration with regadenoson can reduce the frequency and severity of side effects was not known.

Researchers therefore initiated the ASSUAGE study, a single-center randomized, double-blinded, placebo-controlled clinical trial.

There are challenges to standardizing aminophylline use with stress MPI including timing and dosage, Morales reported. “The drug has to be administered after achieving maximal radioisotope uptake, which is typically 90 seconds, and a minimal effective dose should be used to avoid aminophylline adverse effects.”

In the trial, researchers randomly assigned 248 patients undergoing regadenoson-stress SPECT MPI to receive either 75 mg of intravenous aminophylline or a matching placebo, each administered two minutes after regadenoson injection.

The two groups (124 in each) had similar baseline characteristics. The average age was 62, and 45% were women. Following SPECT imaging, researchers also noted no statistically significant difference in ischemic burden between the two arms.

The use of aminophylline was associated with a reduction in diarrhea or abdominal discomfort (OR 0.45, 95% CI 0.21 to 0.97, P=0.04) and in the incidence of diarrhea (OR 0.29, 95% CI 0.09 to 0.9, P=0.024) compared with placebo.

Overall, the use of aminophylline was also significantly associated with a reduction in the secondary endpoints of flushing, feeling hot, dyspnea, chest pain, headache, dizziness, nausea, abdominal discomfort, and diarrhea (44.4% versus 66.9%, OR 0.39, 95% CI 0.24 to 0.66, P<0.001).

Patients in the aminophylline group indicated a higher comfort level, on a scale of 1 to 4, compared with the placebo group (P=0.004).

Specifically, the severity of diarrhea in patients in the aminophylline group was significantly less, on the basis of a severity score between 0 and 3 (0.04 versus 0.17, P=0.001), reported lead author Rami Doukky, MD.

“The more objective Bristol Stool Consistency Scale also indicated that the stool was looser in the placebo group with mean score of 1.02 versus 0.31 in the aminophylline group [P=0.001],” Doukky said, which translated into fewer trips to the bathroom for patients in the intervention arm (0.09 versus 0.33, P<0.001).

Interestingly, researchers found that a subgroup of patients with severe chronic kidney disease received greater benefit from aminophylline (P=0.04), even though regadenoson is cleared by the kidneys and was expected to be associated with more adverse events in patients with chronic kidney disease.

The study had its limitations: It was not adequately powered to detect the minimal impact of aminophylline use on the sensitivity of regadenoson-stress MPI, Doukky reported. He said that a “crossover design, where patients serve as their own controls, would have been optimal to answer this question, but at an added substantial cost and radiation exposure.”

Doukky receives research grant support from Astellas Pharma. All other authors reported no conflicts of interest.

Cutting back on TV viewing — the predominant culprit in adults’ sedentary behavior — could contribute slightly to the national weight loss effort, a small randomized trial suggested.

Among subjects who cut their TV time in half, energy expenditure increased by 119 kcal/day during a three-week intervention (95% CI 23 to 215), while energy decreased by 95 kcal/day among controls (95% CI 254 to 65, P=0.02), according to Jennifer J. Otten, PhD, of Stanford University, and colleagues.

However, there was no significant difference between the intervention and control groups in energy intake, energy balance, or body mass index (BMI), the researchers reported in the December 14/28 Archives of Internal Medicine.

Public health efforts to combat obesity in adults have focused primarily on diet and physical activity, but interest also has increased in strategies to limit sedentary behavior, which is associated with heightened risk of obesity and metabolic syndrome, independent of physical activity.

Studies show that TV couch potatoes expend even even less energy than people engaged in other sedentary behaviors such as reading, writing, or talking on the telephone, and U.S. adults currently average five hours of TV a day.

Previous studies have also demonstrated that limiting TV improved body weight and body composition among children. So, to see if the same would happen with obese adults, Otten and colleagues recruited 36 subjects whose BMI was 25 to 50.

Participants’ mean age was 42 years, 70% were women, and mean baseline BMI was 32.

During the first three weeks of the study (phase 1) all participants’ television viewing was monitored by an electronic device. During week three they wore armbands that measured physiologic and movement parameters that reflected energy expenditure.

The subjects also kept dietary and sleep logs.

After the observational phase, the participants were randomized into two groups.

Phased 2 viewers in the intervention group were allowed to watch only 50% as much TV as they formerly watched. When they reached the maximum time, their TVs were locked off until the following week.

Participants in the control group continued to watch as much TV as they pleased, with screen time monitored electronically.

In Phase 2, daily TV viewing decreased in both groups, from a mean of 4.8 hours to 1.8 hours (P<0.001) in the intervention group and from a mean of 5.3 hours to 4.5 hours (P<0.001) in the control group.

Both groups also reduced their caloric intake, though the difference between them was not significant (P=0.52): Intervention group, −125 kcal/day (95% CI −303 to 52) Control group, −38 kcal/day (95% CI −265 to 190)

The intervention group had a negative energy balance between phase 1 and 2 (−244 kcal/day, 95% CI −459 to −30), which corresponded to a weight loss of approximately 1.5 lb, while controls showed a positive energy balance between the two phases (57 kcal/day, 95% CI −216 to 330, P=0.7).

BMI reductions were greater, although not significantly so, in the intervention group (−0.25 kg/m2, 95% CI −0.45 to −0.05) than in the control group (−0.06 mg/m2, 95% CI −0.43 to 0.31, P=0.33).

There were no changes within or between groups in sleep parameters, which had been included as a secondary outcome because chronic sleep deprivation has been linked with obesity.

These results differed from those seen in studies of children, which “suggests that adults may differ from children in how they respond to reductions in sedentary behaviors,” the investigators wrote.

For example, children may be more susceptible to “advertisement-triggered food demand” stimuli, while routine eating habits are more firmly established and less likely to change quickly in adults.

Limitations of the study included its short duration and the lack of data on whether computer time increased as TV time decreased.

In conclusion, the researchers wrote, decreasing television viewing increased energy expenditure and resulted in a trend toward a negative energy balance, findings that warrant further exploration of this type of intervention to control and prevent obesity in adults.

The study was supported by USDA Hatch Act Funds and by grants from the National Institutes of Health.

No financial disclosures were reported.