HHAL MEDICAL NEWS NOVEMBER 2010
Diet High in Protein, Low on Glycemic Index
Helps Prevent Weight Regain
A
diet high in protein and low on the glycemic index appears to be optimal for weight control following significant weight loss,
according to an international study in the New
England Journal of Medicine.
Researchers randomized some 770 overweight or obese adults
— who had recently lost at least 8% of their body mass — to one of five maintenance diets: high-protein/low-glycemic-index,
high-protein/high-glycemic-index, low-protein/low-glycemic-index, low-protein/high-glycemic-index, or following their country's dietary guidelines.
At 6 months, the high-protein/low-glycemic-index diet group had lost additional weight (-0.38 kg), while the low-protein/high-glycemic-index diet regained the most weight (1.67 kg). Diets that were high
in protein and low on the glycemic index had higher rates of study completion.
The authors conclude
that a high-protein/low-glycemic-index diet "appears to be ideal for the prevention of weight regain."
http://www.nejm.org/doi/full/10.1056/NEJMoa1007137
Metformin Linked to Lower Mortality in Diabetics with Atherothrombosis
Metformin use is associated with reduced all-cause mortality
among diabetic patients with atherothrombotic disease, according to an international, observational study in the Archives of Internal Medicine.
Researchers studied
nearly 20,000 patients with diabetes and a history of coronary
artery disease, cerebrovascular disease, or peripheral arterial disease; slightly more than a third were using metformin at
baseline. During 2 years' follow-up, mortality was lower among metformin users than nonusers
(6% vs. 10%). The difference was observed across numerous subgroups, including patients older than 65, those with histories
of congestive heart failure, and those withchronic kidney disease.
The authors note that metformin
primarily treats hepatic insulin resistance,
which may be an independent cardiovascular risk factor.
They call for a randomized clinical trial to confirm their findings but conclude: "Metformin
use may decrease mortality among patients with diabetes when used as a means of secondary prevention, including subsets of
patients in whom metformin use is not now recommended."
http://archinte.ama-assn.org/cgi/content/short/170/21/1892
ARBs plus ACE Inhibitors,
Used in Combination, Seem to Heighten Cancer Risk
Patients
taking angiotensin-receptor blockers along with angiotensin-converting–enzyme inhibitors — but not ARBs alone — have
a modestly increased risk for cancer, according to a Lancet Oncology meta-analysis.
Researchers, investigating
the reported association between antihypertensive
drugs and cancer, examined data from 70 randomized trials encompassing over 300,000 participants
with a mean follow-up of 3.5 years. Their analysis found no added risk for cancer from ARBs,
beta-blockers, ACE inhibitors, calcium-channel blockers, or diuretics, when compared with placebo. However, the combination of ACE inhibitors and ARBs posed a 14% relative
risk increase.
Commentators say
the finding of no increased risk with most antihypertensives is "hardly surprising," given the short follow-up period.
They also point out that the ACE inhibitor/ARB combination is often used in patients with severe heart failure, who have lower life expectancies.
Lancet
Oncology article
With Vitamin E
Supplements, Risk Is Lower for Ischemic Stroke but Higher for Hemorrhagic Stroke
Widespread use of vitamin E supplements is not recommended.
A plausible theory exists that
vitamin E, an antioxidant, would prevent cardiovascular
disease. The results of prospective randomized
trials, however, have been mostly negative, and some have suggested harm, including excess risk for hemorrhagic stroke (JW Gen Med Nov 13 2008, JW Gen Med Sep 27 2007, and JW Gen Med Aug 2 2005). In this meta-analysis of nine randomized placebo-controlled trials with nearly
119,000 participants, investigators evaluated the effect of vitamin E supplementation on
risk for overall, ischemic, and hemorrhagic strokes.
Seven
trials provided information on overall stroke, and five trials each provided information on ischemic stroke and hemorrhagic stroke. Vitamin E had no effect on risk for overall stroke. Risk for ischemic stroke was 10% lower and risk for hemorrhagic
stroke was 22% higher in vitamin E recipients than in placebo recipients; these differences were significant. Absolute
risk differences, however, were small; 476 people would need to take vitamin E for at least 1 year to prevent one ischemic
stroke, and 1250 people would need to take vitamin E to cause one hemorrhagic stroke.
Medline abstract
Predicting Which
Children Will Become More or Less Overweight or Obese
Most obesity-related behavior
change is not associated with changes in BMI z-scores
in the short term.
Pediatricians
try to identify behaviors in overweight and obese patients that, if modified, might help these patients become less overweight
or obese. Researchers prospectively examined whether obesity-related risk factors and behaviors predict future body-mass
index (BMI) z-scores in 168 overweight and 441 obese children (mean age, 10 years; 75% Latino)
at an urban community health center in Connecticut. At each visit, patients' obesity-related risk behaviors (including
consumption of sugar-sweetened drinks, fast-food meals, high-calorie snacks, fruits and vegetables, breakfast meals, and amount
of television viewing and exercise) were ass essed by patient or parent report, and clinicians encouraged patients to reduce
obesity-related risk behaviors.
At 1 year after initial assessment, BMI z-scores
increased in 41% and 29% of overweight and obese patients, respectively, and decreased in 26% and 38%, respectively. Most
patients reported increases in risk behaviors; 20%–30% reported decreases. The only behavior change significantly associated
with a decrease in BMI z-score was a reduction in the number of meals
eaten out of the house. Presence of Acanthosis
nigricans and obesity in first- and second-degree relatives were
associated with increased
http://www.ncbi.nlm.nih.gov/pubmed/20542293?dopt=Abstract
Fructose Consumption and Risk for Gout
in Women
One daily fructose-sweetened soft drink raised risk for gout by 74%.
Choi
HK et al. JAMA 2010
Nov 10;
Invasive Dental Treatment and Risk for Stroke or MI
Risk for ischemic stroke or myocardial infarction was transiently increased during the first 4 weeks
after treatment.
Studies have suggested
that intensive periodontal treatment leads to endothelial
dysfunction and elevated markers of inflammation. Whether these changes
raise risk for vascular events is not known. Using U.S. Medicaid claims data, researchers evaluated risk for adverse vascular
events during the 24 weeks after invasive dental work. Individual patients served as their own controls (rates of vascular
events were assessed during periods with and without exposure to invasive dental procedures). The final sample consisted of
1152 patients (41% with histories of coronary artery
disease [CAD]) who were hospitalized for ischemic stroke or myocardial
infarction (MI) and had undergone invasive dental procedures.
Risk for ischemic stroke
or MI was transiently increased during the first 4 weeks after an invasive dental procedure (incidence ratio, 1.5) but not
during weeks 5 through 24, relative to baseline (periods more than 24 weeks after any invasive dental procedure). In sensitivity
analyses, the findings did not change when analysis was limited to patients with no histories of having filled antiplatelet
drug prescriptions, or when patients with recently diagnosed diabetes or CAD were excluded.
Vytorin Reduces Vascular Events in Patients with Chronic
Kidney Disease
Ezetimibe/simvastatin
(marketed as Vytorin) lowers the risk for major vascular events in patients with chronic kidney disease, according to an industry-funded, multicenter study presented over the weekend at the American Society of Nephrology's
annual meeting.
The SHARP study, which enrolled nearly 9500 adults with chronic kidney
disease, found that the incidence of myocardial infarction,
cardiac death, stroke, or revascularization over roughly 5 years' follow-up was significantly lower in patients randomized
to ezetimibe/simvastatin than in those assigned to placebo (absolute difference between the groups, 3%). The difference was
driven mainly by reductions in nonhemorrhagic stroke and revascularization procedures.
Ezetimibe/simvastatin
did not increase the risk for cancer or cancer-related mortality, a concern raised in previous studies.
Manufacturer's press release
Statins Safely Reduce CV Risk
in Patients with Abnormal Liver Tests
Statins safely reduce cardiovascular events in patients with moderately abnormal liver enzymes, according to a post hoc analysis from the GREACE study published
in the Lancet.
In GREACE, 1600
adults with coronary heart disease and
dyslipidemia were randomized to atorvastatin therapy or usual care (which could include a statin) for 3 years. Among some
440 participants with moderately abnormal liver function at enrollment (less than three times the upper limit of normal),
those using statins were less likely than nonusers to experience cardiovascular events (10% vs. 30%). Statins were more beneficial
in patients with abnormal than with normal liver enzymes.
Patients with abnormal
liver function who received statins had improvements in liver enzymes. Of all statin recipients, less than 1% had statin-related
adverse liver effects.
The authors say the risk-benefit profile favors statin therapy
"even for patients with moderately abnormal liver tests." A commentator is confident that prospective research will
confirm the benefits.
http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(10)61272-X/fulltext
The
more intensive the statin treatment, the better the results
Further reductions in LDL cholesterol
safely produce definite further reductions in the incidence of heart attack, of revascularisation, and of ischaemic stroke,
with each 1•0 mmol/L reduction reducing the annual rate of these major vascular events
by just over a fifth. There was no evidence of any threshold within the cholesterol range studied, suggesting that reduction
of LDL cholesterol by 2 to 3 mmol/L would reduce risk by about 40% to 50%.
http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(10)61350-5/abstract
Regular Alcohol Use Associated with Less CV Risk Than Binge Drinking
A
comparison of the very different drinking behaviors between Belfast,
Northern Ireland, and three French cities suggests that binge drinking carries more cardiovascular risk than the same
amount of alcohol consumed over a longer period. The study appears in BMJ.
Researchers
studied some 10,000 middle-aged men, taking histories of their drinking habits at baseline and following them for 10 years.
Binge
drinking (five drinks, or 50 g of ethanol, at least one day a week) was nearly 20-fold more prevalent in Belfast than in France,
where daily drinking was more common than in Belfast. The annual incidence of the primary outcome — myocardial infarction or coronary death —
was 5.6 per 1000 participants in Belfast, versus 2.8 in France. The amount of alcohol consumed weekly, however, was almost
the same.
In the entire cohort, after adjustment for cardiovascular risk factors, the hazard
ratio for the primary outcome was 1.97 for binge drinkers relative
to regular drinkers
http://www.bmj.com/content/341/bmj.c6077.full
Dual Antiplatelet Therapy and ED Visits
The risk for hemorrhage associated with dual antiplatelet therapy is "substantial," according to an Archives
of Internal Medicine study.
To measure the
risk, researchers analyzed national data from U.S. emergency
department visitsover 3 years; ED visits for hemorrhagic and other adverse events attributable to clopidogrel plus aspirin were compared with visits attributable to warfarin use.
After
adjusting for prescribing frequency, the rate of ED visits for hemorrhage-related adverse events was higher among patients
receiving warfarin than those receiving clopidogrel plus aspirin (3.7 vs. 1.2 visits per 1000 outpatient prescription visits).
The risk for hospitalization for acute hemorrhage was similar between treatment groups. Roughly 60% of the visits for dual antiplatelet therapy were for minor hemorrhages,
such as nosebleeds, bruising, or small cuts.
The authors conclude: "The high frequency
of minor hemorrhages with clopidogrel plus aspirin suggests that efforts targeted at educating patients to anticipate and
recognize such events so as to optimize patient adherence to therapy will be important."
http://archinte.ama-assn.org/cgi/content/abstract/170/21/1926
FDA Requests Withdrawal of Darvon, Darvocet from U.S. Market
The FDA is
requesting that manufacturers of the painkiller propoxyphene pull the drug from the market because of concerns over cardiotoxicity. (Propoxyphene is marketed alone as Darvon and combined with acetaminophen as Darvocet.)
The
agency's request is based on data showing that, even when taken at therapeutic doses, the drug can lead to potentially dangerous changes in the heart's electrical activity, including prolonged PR and QT intervals and widened QRS complex.
The
FDA advises clinicians to stop prescribing propoxyphene and to ask current users to discontinue the drug.
http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm234389.htm
Tricyclics Lighten Headache Burden in Patients with Migraine and Tension Headaches
Tricyclics are more effective than selective serotonin
reuptake inhibitors.
For decades, clinicians
have prescribed tricyclic antidepressant drugs for patients with migraine and tension headaches. In this meta-analysis of 37 randomized trials (average duration, 10 weeks) involving
nearly 3200 patients (73% women; mean age, 40), investigators compared the efficacy of tricyclics with that of placebo, selective serotonin reuptake inhibitors (SSRIs), and β-blockers in the treatment of migraine and tension headaches. Amitriptyline and clomipramine were the most common tricyclics in the trials.
Tricyclics
were compared with placebo in 20 trials. Tricyclics were significantly more effective than placebo in reducing the burden
of both headache types: Tricyclics reduced the mean number of headaches monthly by 1.4 for migraine (from a baseline of 4.7)
and by 6.9 for tension headache (from
a baseline of 16.9). For both headache types, tricyclics were more likely to result in at least 50% improvement in patients'
headaches and to result in fewer doses of analgesics. Furthermore, the beneficial effect of tricyclics strengthened with time.
In
the eight trials in which tricyclics were compared with SSRIs, tricyclics were more likely to result in at least 50% improvement
in both migraine and tension headaches. Three trials compared tricyclics and β-blockers for migraine; both classes of
drugs were similarly effective. Although patients taking tricyclics experienced more side effects (e.g., dry mouth) than patients
taking placebo or SSRIs, side effects did not result in increased dropout
rates.
http://www.ncbi.nlm.nih.gov/pubmed/20961988?dopt=Abstract
Inhaled corticosteroid use: A diabetes risk
In patients with respiratory disease, inhaled corticosteroid use
is associated with modest increases in the risks of diabetes onset and diabetes progression.
The risks are more pronounced at the higher doses currently prescribed in the treatment of chronic obstructive pulmonary disease. The American Journal of Medicine
How much warfarin for patients with impaired kidney function?
Warfarin is the most commonly prescribed oral
anticoagulant. This study shows that patients with moderate to severe kidney impairment require
significantly less of the drug than those with minimal or no kidney impairment and offers dosing recommendations by
kidney function level. Since chronic kidney disease is not uncommon in patients with cardiovascular morbidity, dosing adjustments
may apply to many long-term warfarin users. (Full-text access is time-limited.) American Journal of Kidney Diseases
Rivastigmine: Don't use it in critical care
Rivastigmine did not decrease duration of delirium and might have
increased mortality. These authors therefore recommend against the use of rivastigmine to treat delirium in critically ill
patients. (Free registration required.) The Lancet
When memantine is discontinued
In this retrospective chart review, nursing home residents who
had been taking memantine for Alzheimer's disease symptoms or who had been discontinued
from taking it for 60+ days were identified. Symptoms showed worsening of mood and cognition in the discontinued group.
Journal of the American Medical Directors Association
Stress takes a toll on Americans' daily lives, survey shows
A Harris Interactive survey of
1,134 Americans found that 76% of them cited money as a source of stress in 2010 compared with 71% in 2009. Respondents
also said that stress had influenced their daily lives in the previous month, with 31% skipping
meals, 40% overeating or eating unhealthy foods, and 44% losing sleep. USA TODAY
Obesity in childhood may persist later in life, study says
A study in The Journal of the American Medical Association found
that obese teenagers are 16 times more likely to become severely obese in their 30s compared with adolescents who were normal-weight
or overweight. The risk of developing severe obesity in adulthood was highest among black female adolescents, the study found. WebMD
CONCLUSIONS
In patients
requiring stenting of large coronary arteries, no significant differences were found among
sirolimus-eluting, everolimus-eluting, and bare-metal stents with respect to the rate of death or myocardial infarction.
With the two drug-eluting stents, similar reductions in rates of target-vessel revascularization were seen. (Funded by the
Basel Cardiovascular Research Foundation and the Swiss National Foundation for Research; Current Controlled Trials number,
ISRCTN72444640.)
http://www.nejm.org/doi/full/10.1056/NEJMoa1009406?query=OF
Vitamin
B Supplementation and Cognition
In older men, supplementation did not affect cognition.
Because high plasma
homocysteine levels are associated with cognitive impairment in epidemiologic
studies, in multiple clinical trials researchers have examined whethervitamin B supplementation — which lowers homocysteine levels — improves cognition
or delays onset of cognitive impairment in older adults; results have been mostly negative. In a new study, Australian researchers
randomized 299 community-dwelling hypertensive men (age, 75) without dementia to receive either placebo or a
combination of vitamin B6,vitamin B12, and folic acid.
During 2 years of treatment, no differences between groups were noted on several measures of cognition. Even in subgroups in which benefit seemed likely — men with
high baseline homocysteine levels ( 15 µmol/L) and men with mild
cognitive impairment at baseline — the investigators found no
benefit from vitamin B supplementation.
Medline abstract
Omega-3 Supplements Do Not Slow Cognitive Decline in Alzheimer Disease
Contrary to epidemiological studies suggesting that docosahexaenoic acid
(DHA) might lower risk for Alzheimer disease,
a randomized trial in JAMA has found that DHA
does not slow cognitive decline in patients with AD.
Researchers randomized some 400
adults with mild-to-moderate AD to receive DHA (2 g daily) or placebo for 18 months. At the end of treatment, there was no
difference between the groups in the rate of cognitive decline, as measured by the Alzheimer's Disease Assessment Scale and the Clinical Dementia Rating sum
of boxes.
Given their findings, the authors conclude that "there is no basis
for recommending DHA supplementation" for patients with AD.
JAMA article
Vapor Rub May Improve Children's
Overnight Cold Symptoms
Vapor rub may
help relieve some overnight cold symptoms in children and improve their sleep, according to an industry-funded study in Pediatrics.
Researchers randomized
nearly 140 children (aged 2 to 11 years) with upper
respiratory infections to have parents rub their chests and necks with
vapor rub, petrolatum ointment, or nothing for one night. According to parent surveys completed the following morning, all
groups showed improvement, but children treated with vapor rub had the greatest improvement in sleep, cough, and congestion,
relative to the prior night. Rhinorrhea severity after treatment did not differ among the groups. Nearly half of the vapor
rub group reported a mild adverse event, such as burning of the skin, eyes, or nose.
The authors say
vapor rub "helps to fill the therapeutic void" for safe and effective pediatric cold remedies.
Pediatrics article
Habitual
Chocolate Intake and Vascular Disease: A Prospective Study of Clinical Outcomes in Older Women
Arch Intern Med. 2010;170(20):1857-1858.
doi:10.1001/archinternmed.2010.396
Cocoa, the principal ingredient of chocolate, is a rich source of
flavonoids. Higher flavonoid intakes are associated with a
lower risk of cardiovascular disease, and flavonoid-rich cocoa and
chocolate can reduce blood pressure and improve endothelial function.1 Interest in the potential of cocoa and chocolate to
prevent cardiovascular disease has been stimulated by recent prospective
cohort studies in which consuming more than 2.25 g/d of cocoa (average,
4.2 g/d) was associated with a 50% lower risk of cardiovascular
mortality.2-3 Our objective was to investigate the
relationship between chocolate consumption and atherosclerotic vascular
disease (ASVD) events in a prospective study of older women followed
up for 9.5 years
http://archinte.ama-assn.org/cgi/content/extract/170/20/1857?ct
Annual Low-Dose CT Screening Better Than Chest X-Ray for Reducing Lung
Cancer Mortality
Annual low-dose
computed tomography cuts more lung cancer deaths than chest radiography among high-risk patients, according to early, as-yet unpublished
findings from the National Lung Screening Trial released by the National
Cancer Institute.
More than 53,000 current or former heavy smokers (aged 55
to 74) without signs or symptoms of lung cancer were randomized to undergo low-dose CT or chest radiography at baseline and then
annually for 2 years. During follow-up, lung cancer mortality was 20% lower with CT than with radiography. (Based on this
finding, the trial's data and safety monitoring
board recommended stopping the study.)
The
NCI's Dr. Christine Berg said: "This is the first time that we have seen clear evidence of a significant reduction
in lung cancer mortality with a screening test in a randomized
controlled trial. The fact that low-dose helical CT provides a decided benefit is a result that will have implications
for the screening and management of lung cancer for many years to come."
National Cancer Institute news release
Which Inflammatory Marker Should We Measure? ESR, CRP, or Both?
C-reactive protein testing should be
given preference over erythrocyte sedimentation rate for most hospitalized
patients.
Colombet I et al. Am J Med 2010 Sep 123:863.e7
Memantine for Parkinson Disease Dementia
and Lewy Body Dementia
A randomized trial shows a marginal benefit for LBD and has no effect
for PDD.
Emre M et al. Lancet
Neurol 2010 Oct 9:969
Measures of Physical Capability Predict
Early Mortality
Grip strength, walking speed, and chair rising were markers in elders.
Cooper R et al. BMJ 2010 Sep 9; 341:c4467
