martes, 18 de diciembre de 2012

Daily Doses of a New Probiotic Reduces 'Bad' and Total Cholesterol

Two daily doses of a probiotic lowered key cholesterol-bearing molecules in the blood as well as "bad" and total cholesterol, in a study presented at the American Heart Association's Scientific Sessions 2012.

Probiotics are live microorganisms (naturally occurring bacteria in the gut) thought to have beneficial effects; common sources are yogurt or dietary supplements.
In previous studies, a formulation of the bacteria, known as Lactobacillus reuteri NCIMB 30242, has lowered blood levels of LDL or "bad" cholesterol.
Such treatments are drawing increasing medical attention as researchers unravel how supplementing gut bacteria (microbiome) with probiotics can play a role in health and certain chronic diseases such as heart disease, said Mitchell L. Jones, M.D., Ph.D., lead author of the study and a research assistant in the Faculty of Medicine at McGill University in Montreal.
Researchers investigated whether the same probiotic could lower LDL and reduce blood levels of cholesterol esters -- molecules of cholesterol attached to fatty acids, a combination that accounts for most total blood cholesterol and has been tied to cardiovascular disease risk.
Researchers tracked cholesterol esters bound to saturated fat, which have been linked to dangerous arterial plaque buildup and occur at higher levels in coronary artery disease patients.
The study involved 127 adult patients with high cholesterol. About half the participants took L. reuteriNCIMB 30242 twice a day, while the rest were given placebo capsules.
Those taking the probiotic had LDL levels 11.6 percent lower than those on placebo after nine weeks. Furthermore, cholesterol esters were reduced by 6.3 percent and cholesterol ester saturated fatty acids by 8.8 percent, compared with the placebo group.
For the first time, research shows that the probiotic formulation can reduce cholesterol esters "and in particular reduce the cholesterol esters associated with 'bad' saturated fatty acids in the blood," said Jones, co-founder and chief science officer of Micropharma, the company that formulated the probiotic.
Furthermore, people taking the probiotic had total cholesterol reduced by 9.1 percent. HDL "good" cholesterol and blood triglycerides, a dangerous form of fat in the blood, were unchanged.
Scientists have proposed that Lactobacillus bacteria alone may impact cholesterol levels in several ways, including breaking apart molecules known as bile salts. L. reuteri NCIMB 30242 was fermented and formulated to optimize its effect on cholesterol and bile salts.
Based on correlations between LDL reduction and bile measurements in the gut, the study results suggest the probiotic broke up bile salts, leading to reduced cholesterol absorption in the gut and less LDL.
The probiotic worked at doses of just 200 milligrams a day, far lower than those for soluble fiber or other natural products used to reduce cholesterol.
"Most dietary cholesterol management products require consumption between 2 to 25 grams a day," Jones said.
Patients appear to tolerate the probiotic well and the probiotic strain L. reuteri has a long history of safe use, he said.
Because of the small number of patients involved in the study, researchers aren't sure if the impact of the probiotic differs between men and women or among ethnic groups.
American Heart Association. "Daily doses of a new probiotic reduces 'bad' and total cholesterol." ScienceDaily, 5 Nov. 2012. Web. 18 Dec. 2012.

Multivitamins Fail, But Novel Lipid Tx Promising


 Day two at the American Heart Association meeting featured the latest findings from researchers for the Physicians' Health Study II and promising, but very early results, from a study of an investigational lipid-lowering antibody treatment, a pair of findings highlighted in this exclusive InFocus video report.
Harvard's Elliott Antman, MD, who chaired the scientific program here, said it is not surprising that daily vitamin therapy did not reduce the risk of cardiovascular events in a population of healthy men, who also happen to be physicians. And, he noted, that the same researchers recently reported that the daily vitamins did slightly reduce the risk for developing cancer.
More promising findings came from studies of an investigational antibody treatment for dyslipidemia -- a PCSK9 inhibitor known now as AMG 145 -- that achieved significant reductions in LDL among patients who can't tolerate statin therapy and those with heterozygous familial hypercholesterolemia. The antibody treatment is given subcutaneously and that may present a challenge, Antman told Peggy Peck, MedPage Today Editor-in-Chief.
From the American Heart Association:

Daily Multivitamin Use Among Men Does Not Reduce Risk of Major Cardiovascular Events, Study Suggests

In a randomized study that included nearly 15,000 male physicians who were middle-aged or older, daily multivitamin use for more than 10 years of treatment and follow-up did not result in a reduction of major cardiovascular events, heart attack, stroke, or death from cardiovascular disease, according to a study appearing in November 7 issue of JAMA, a theme issue on cardiovascular disease.

"Despite uncertainty regarding the long-term health benefits of vitamins, many U.S. adults take vitamin supplements to prevent chronic diseases or for general health and well-being," according to background information in the article. Individuals who believe they are deriving benefits from supplements may be less likely to engage in other preventive health behaviors. "Although multivitamins are used prevent vitamin and mineral deficiency, there is a perception that multivitamins may prevent cardiovascular disease (CVD). Observational studies have shown inconsistent associations between regular multivitamin use and CVD, with no long-term clinical trials of multivitamin use."
Howard D. Sesso, Sc.D., M.P.H., of Brigham and Women's Hospital and Harvard Medical School, Boston, and colleagues analyzed data regarding multivitamin use and major cardiovascular events from the Physicians' Health Study (PHS) II, a large-scale trial testing the effects of long-term use of a common multivitamin on the risk of major cardiovascular events and cancer. The Physicians' Health Study II is a randomized, placebo-controlled trial that began in 1997 with continued treatment and follow-up through June 1, 2011. A total of 14,641 male U.S. physicians initially 50 years of age or older (average, 64 years), including 754 men with a history of CVD at randomization, were enrolled. This analysis measured the composite end point of major cardiovascular events, including nonfatal myocardial infarction (MI; heart attack), nonfatal stroke, and death from CVD. Secondary outcomes included heart attack and stroke individually. Participants were randomized to multivitamin (n = 7,317) or placebo (n = 7,324).
During a median (midpoint) follow-up of 11.2 years, 1,732 men had major cardiovascular events, including 652 cases (first events) of heart attack and 643 cases of stroke, and 829 men had cardiovascular death, with some men experiencing multiple events. A total of 2,757 (18.8 percent) men died during follow-up (multivitamin, n = 1,345; placebo, n = 1,412). In an analysis of the rate of events for men in each group, the researchers found that there was no significant effect of a daily multivitamin on major cardiovascular events, or total MI or total stroke. Taking a daily multivitamin was not significantly associated with a reduction in CVD mortality. There were fewer total deaths among multivitamin users, but this difference was not statistically significant.
The authors also found no significant effect of a daily multivitamin on rates of congestive heart failure, angina, and coronary revascularization. Also, the effect of a daily multivitamin on total MI, total stroke, and other cardiovascular end points did not differ between men with and without CVD at the beginning of the study.
"The PHS II represents to our knowledge the only large-scale, randomized, double-blind, placebo-controlled trial testing the long-term effects of a commonly available multivitamin in the prevention of chronic disease," the authors write. "These data do not support multivitamin use to prevent CVD, demonstrating the importance of long-term clinical trials of commonly used nutritional supplements. Whether to take a daily multivitamin requires consideration of an individual's nutritional status, because the aim of supplementation is to prevent vitamin and mineral deficiency, plus consideration of other potential effects, including a modest reduction in cancer and other important outcomes in PHS II that will be reported separately."
Editorial: Multivitamins in Prevention of Cardiovascular Disease
In an accompanying editorial, Eva M. Lonn, M.D., M.Sc., of McMaster University and Hamilton General Hospital, Hamilton, Ontario, Canada, writes that "robust data from multiple trials clearly confirm that CVD cannot be prevented or treated with vitamins."
"Nonetheless, many people with heart disease risk factors or previous CVD events lead sedentary lifestyles, eat processed or fast foods, continue to smoke, and stop taking lifesaving prescribed medications, but purchase and regularly use vitamins and other dietary supplements, in the hope that this approach will prevent a future myocardial infarction or stroke. This distraction from effective CVD prevention is the main hazard of using vitamins and other unproven supplements. The message needs to remain simple and focused: CVD is largely preventable, and this can be achieved by eating healthy foods, exercising regularly, avoiding tobacco products, and, for those with high risk factor levels or previous CVD events, taking proven, safe, and effective medications."
JAMA and Archives Journals. "Daily multivitamin use among men does not reduce risk of major cardiovascular events, study suggests." ScienceDaily, 5 Nov. 2012. Web. 18 Dec. 2012.

miércoles, 5 de diciembre de 2012

Aromatherapy: Two Hours Is Too Much


Aromatherapy can help patients relax by initially reducing heart rate and blood pressure significantly, but those benefits may be reversed if exposure lasts more than an hour, researchers found.
Presence of essential oil vapor -- the vapor from aromatherapy -- was significantly associated with reduced blood pressure and heart rate from 15 minutes to 60 minutes after exposure (P<0 .05=".05" a="a" according="according" among="among" and="and" chuang="chuang" colleagues.="colleagues." healthy="healthy" in="in" kai-jen="kai-jen" medical="medical" of="of" p="p" phd="phd" sample="sample" spa="spa" taipei="taipei" taiwan="taiwan" to="to" university="university" workers="workers">
However, exposure to the oil vapor for periods of 90 to 120 minutes was significantly associated with increased blood pressure and heart rate (P<0 .05=".05" em="em" in="in" online="online" style="border: 0px; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;" the="the" they="they" wrote="wrote">European Journal of Preventive Cardiology
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"The inhalation of air pollutants has been reported to induce pulmonary oxidative stress, inflammation, and autonomic dysfunction," they noted, adding that those "biological processes may also be applied to the adverse effects of the total volatile organic compound exposure on cardiovascular health."
The researchers analyzed associations between heart and blood pressure with oil vapors generated by an aromatherapy machine known as an ultrasonic atomizer in 100 healthy, nonsmoking Taiwanese spa workers. Participants were mostly female (51%); younger (average age 22.5); and had an average heart rate of 71.2 beats/minute, an average systolic blood pressure of 123.5 mmHg, and an average diastolic blood pressure of 84.1 mmHg.
Each participant received a baseline screening and was exposed to essential oil vapor for 2 hours at three study site visits. During the 2-hour exposures, participant blood pressure and heart rate were recorded at 15-minute intervals. The researchers also measured levels of volatile organic compound -- the aromatherapy oils -- in the environment during the 2-hour period at 1-minute intervals.
Average levels of volatile organic compounds were 82.2 parts per billion, and levels of aromatherapy oils, blood pressure, heart rate, and study room humidity and temperature did not vary significantly between visits.
Mean declines in blood pressure and heart rate were greatest at 45 minutes into the aromatherapy sessions, with systolic blood pressure lowered by an average 2.10 mmHg (95% CI -1.40 to -2.80), diastolic blood pressure lowered by an average 1.30 mmHg (95% CI -0.70 to -1.90), and heart rate lowered by an average 2.21 beats/minute (95% CI -1.61 to -2.81), which were significant at P<0 .05.=".05." p="p">
Declines in systolic blood pressure and heart rate were smallest at 15 minutes, while diastolic blood pressure declines were smallest at 60 minutes.
At 90 minutes to 120 minutes, heart rate and blood pressure were significantly higher (P<0 --="--" .05=".05" 0.66="0.66" 0.79="0.79" 0.93="0.93" 1.70="1.70" 1.79="1.79" 120="120" 2.19="2.19" 2.47="2.47" 2.86="2.86" 3.59="3.59" all="all" and="and" at="at" beats="beats" blood="blood" by="by" ci="ci" diastolic="diastolic" elevated="elevated" heart="heart" highest="highest" mean="mean" minute="minute" minutes="minutes" mmhg="mmhg" p="p" pressure="pressure" raised="raised" rate="rate" systolic="systolic" to="to" was="was" were="were">
They concluded that 1-hour aromatherapy exposure "could be a useful method of stress relief," but that prolonged exposure for over an hour "may be harmful to cardiovascular health in young, healthy subjects."
They added that future studies could measure long-term cardiopulmonary and psychological outcomes of vaporized essential oil exposure.
The authors noted that the study was limited by missing measures for other possible environmental air pollutants, limited intra-individual measures, additional unmeasured confounders, relevance of short-term heart rate and blood pressure effects on long-term outcomes, and limited numbers of measures from participants.
Tomado de Medpagetoday.com  : Chuang KJ, et al "The effect of essential oil on heart rate and blood pressure among solus por aqua workers" Eur J Prev Cardiol 2012; DOI: 10.1177/2047487312469474.

Sleep Duration Affects Hunger Differently in Men and Women

A new study suggests that increasing the amount of sleep that adults get could lead to reduced food intake, but the hormonal process differs between men and women.


"Restricting sleep in healthy, normal weight participants has limited effects on metabolic risk factors and may affect food intake regulating hormones differently in men and women," said Marie-Pierre St-Onge, PhD, FAHA, the study's principal investigator. "We were surprised by the lack of a significant effect of sleep on glucose and insulin, leptin, and sex differences in the hunger-stimulating hormone ghrelin and the satiety hormone GLP-1."
The study, appearing in the November issue of the journal Sleep, tracked the sleep duration, glucose dysregulation, and hormonal regulation of appetite in 27 normal weight, 30- to 45-year-old men and women. Participants provided fasting blood draws, and they were studied under two sleep conditions: Short (4 hours) or habitual (9 hours). Short sleep increased total ghrelin levels in men but not women and reduced GLP-1 levels in women but not in men, a sex difference that has not been reported before. The results suggest that the common susceptibility to overeat during short sleep is related to increased appetite in men and reduced feelings of fullness in women.
"Our results point to the complexity of the relationship between sleep duration and energy balance regulation," St-Onge said. "The state of energy balance, whether someone is in a period of weight loss or weight gain, may be critical in the metabolic and hormonal responses to sleep restriction."
According to the authors, this is the largest controlled clinical investigation of the effects of sleep reduction on hormonal regulation of food intake. The results support a causal role of sleep duration on energy intake and weight control.
American Academy of Sleep Medicine (AASM). "Sleep duration affects hunger differently in men and women." ScienceDaily, 29 Nov. 2012. Web. 5 Dec. 2012.