HHAL MEDICAL NEWS JULY 2011
Vegetarian, High-Fiber
Diets Linked to Lower Risk for Diverticular Disease
Vegetarian
and high-fiber diets are each associated with lower risk for hospitalization or death from diverticular disease, according
to a prospective study in BMJ.
Some
47,000 "generally health conscious" adults in the U.K. completed dietary and lifestyle questionnaires and then were
followed for nearly 12 years. About one third of participants said they were vegetarian.
During
follow-up, there were 806 hospital admissions and 6 deaths from diverticular disease. After multivariable adjustment, vegetarians had a roughly 30% lower risk for diverticular disease compared with meat eaters,
and participants in the highest quintile of fiber intake had about a 40% reduced risk compared with those in the lowest quintile.
The
authors note that vegetarianism and high fiber intake are "correlated with rapid bowel transit times and increased frequency
of bowel movements, which could be the biological mechanism" underlying the lower risk for diverticular disease observed
here.
BMJ article (Free)
An
Endorsement for Nitrofurantoin in UTI
Prevalent
resistance to other drugs makes this old standby a cost-effective alternative for urinary tract infections.
Uncomplicated urinary tract infection (UTI) has become surprisingly complicated
to treat in recent years because of growing prevalence of microbial resistance to trimethoprim-sulfamethoxazole (TMP-SMX)
and quinolones. Many experts now propose resurrection of the venerable antibiotic nitrofurantoin as a first-line treatment
for uncomplicated cystitis.
Mayo Clinic researchers constructed a decision tree to analyze
the costs of common empirical antibiotic choices for uncomplicated UTI at different community levels of drug resistance. The
model included costs of the drugs and of complications such as requisite retreatment, development of pyelonephritis, and development
of vaginal candidiasis.
When 3-day courses of TMP-SMX or a fluoroquinolone
were compared with a standard 5-day course of nitrofurantoin, the model indicated that nitrofurantoin became the most cost-effective
option when the community's level of TMP-SMX resistance exceeded 17% and its quinolone resistance exceeded 12%. (Below
these levels, the 3-day drug with the least resistance was favored.) Recent surveys indicate that TMP-SMX resistance exceeds
15% everywhere in the U.S. and exceeds 40% in some areas; fluoroquinolone resistance is as high as 20% in some regions.
Medline abstract (Free)
Does the HbA1c Criterion for Prediabetes Predict Incident
Diabetes?
Measuring both fasting glucose and glycosylated hemoglobin levels might be the best method.
The American Diabetes Association recently added a new
criterion for diagnosis of prediabetes — glycosylated hemoglobin (HbA1c) level of 5.7% to 6.4%. To evaluate this new criterion, Japanese investigators studied 6241 people who had five or six consecutive
annual health examinations that included measurements of fasting glucose and HbA1c levels.
At
their baseline examinations, 2092 patients were identified as prediabetic: 60% by impaired fasting glucose (IFG; 100–125
mg/dL) alone, 20% by HbA1c alone, and 20% by both tests. During
a mean 4.7-year follow-up, 338 patients progressed to diabetes, of whom 292 (86%) had been identified as prediabetic at baseline:
32% by IFG alone, 9% by HbA1c alone, and 46% by both tests. Both
IFG alone and HbA1c alone predicted incident diabetes equally strongly,
with multivariate-adjusted hazard ratios of about 6, compared with that for baseline normoglycemia. Patients who were prediabetic
by both criteria at baseline were 32 times more likely to progress to diabetes than those who were normoglycemic.
Adding Exercise to Diet in Early
Type 2 Diabetes
Brisk walking, added to intensive dietary intervention, did not result in additional lowering of glycosylated
hemoglobin.
Andrews RC et al. Lancet 2011 Jun 25;
Hu FB. Lancet 2011 Jun 25;
Sodium
and Potassium Intake and Mortality Among US Adults
Prospective Data From the Third National Health and Nutrition Examination Survey
Quanhe Yang, PhD; Tiebin
Liu, MSPH; Elena V. Kuklina, MD, PhD; W.
Dana Flanders, MD, ScD; Yuling Hong, MD, PhD; Cathleen
Gillespie, MS; Man-Huei Chang, MPH; Marta
Gwinn, MD; Nicole Dowling, PhD; Muin
J. Khoury, MD, PhD;Frank B. Hu, MD, PhD
Arch Intern Med. 2011;171(13):1183-1191. doi:10.1001/archinternmed.2011.257
Background Several epidemiologic studies suggested
that higher sodium and lower potassium intakes were associated
with increased risk of cardiovascular diseases (CVD). Few studies have examined joint effects of dietary sodium and potassium intake
on risk of mortality.
Methods To investigate estimated usual intakes of sodium and
potassium as well as their ratio in relation to risk of all-cause
and CVD mortality, the Third National Health and Nutrition Examination
Survey Linked Mortality File (1988-2006), a prospective cohort
study of a nationally representative sample of 12 267 US adults,
studied all-cause, cardiovascular, and ischemic heart (IHD) diseases
mortality.
Results During a mean follow-up period of 14.8 years, we documented
a total of 2270 deaths, including 825 CVD deaths and 443 IHD deaths.
After multivariable adjustment, higher sodium intake was associated
with increased all-cause mortality (hazard ratio [HR], 1.20; 95%
confidence interval [CI], 1.03-1.41 per 1000 mg/d), whereas higher potassium intake was associated with lower
mortality risk (HR, 0.80; 95% CI, 0.67-0.94 per 1000 mg/d). For
sodium-potassium ratio, the adjusted HRs comparing the highest quartile
with the lowest quartile were HR, 1.46 (95% CI, 1.27-1.67) for
all-cause mortality; HR, 1.46 (95% CI, 1.11-1.92) for CVD mortality;
and HR, 2.15 (95% CI, 1.48-3.12) for IHD mortality. These
findings did not differ significantly by sex, race/ethnicity, body
mass index, hypertension status, education levels, or physical activity.
Conclusion: Our findings suggest
that a higher sodium-potassium ratio is associated with significantly
increased risk of CVD and all-cause mortality, and higher sodium intake is associated with increased
total mortality in the general US population.
Salt Restriction: Updated Analysis
Finds No Definite Proof of Benefit
Reductions
in dietary salt are not followed by reductions in all-cause mortality or cardiovascular events, according to an updated Cochrane
meta-analysis in the American Journal of Hypertension.
Researchers
examined seven randomized, controlled trials encompassing some 6300 participants who either restricted salt intake or acted
as controls. Studies included normotensives, hypertensives, mixed populations, and patients with heart failure.
Salt reduction was associated with a mean decrease in systolic blood pressure between 1 and 4 mm Hg.
Rates of mortality and cardiovascular events were not significantly lowered among normotensives or hypertensives. Patients with heart failure showed an increased risk for all-cause mortality after salt restriction.
Although
the authors say their findings are not inconsistent with "the belief that salt reduction is beneficial in normotensive
and hypertensive people," they admit that their conclusions are hampered by the small amount of evidence. They call for
rigorous research "capable of definitively demonstrating the [cardiovascular] benefit of dietary salt reduction."
[Editor's note: The American Journal of Hypertension has not yet
posted this article online, although the embargo has passed. We've linked to the journal's advance online publication
page, where the article should appear shortly.]
American
Journal of Hypertension advance online publication page (Free)
Smoking
During Pregnancy Linked to Increased Risk for Birth Defects
Maternal
smoking during pregnancy is associated with increased risks for a wide variety of birth defects, according to a meta-analysis
in Human Reproduction Update.
Researchers
examined some 100 studies comprising nearly 175,000 birth defect cases and more than 11.5 million unaffected controls. They
found that maternal smoking was tied to significantly increased risks for certain types of birth defects, including:
·
Limb
reduction, odds ratio, 1.26
·
Clubfoot,
1.28
·
Eye,
1.25
·
Oral
clefts, 1.28
·
Gastroschisis,
1.50
·
Hernia,
1.40
The authors conclude: "These specific defects should be included in ... educational
information to encourage more women to quit smoking before or early on in pregnancy, and to particularly target younger women
and those from lower socioeconomic groups, in which smoking prevalence is greatest."
Human
Reproduction Update article (Free)
Chantix Linked to Cardiovascular Events in Patients Free of CVD
The smoking-cessation drug varenicline (Chantix) is associated
with an increased risk for adverse cardiovascular events among smokers free of cardiovascular disease at baseline, according
to a meta-analysis in the Canadian Medical Association Journal.
Researchers
analyzed data from 14 clinical trials comparing varenicline with placebo among some 8200 tobacco users. Varenicline users had a 72% increased risk for any ischemic or arrhythmic adverse cardiovascular event, compared
with placebo users (absolute risk: 1.06% vs. 0.82%). The authors cite a published finding that 10 people would need
to be treated with varenicline for one additional person to quit smoking, and they estimate that 28 would need to be treated
for one person to experience a cardiovascular event.
The article's senior author
told the New York Times that
varenicline should be pulled from the shelves: "I don't see how the FDA can leave Chantix on the market." The
FDA had recently warned about increased cardiovascular risk among patients with existing cardiovascular disease.
CMAJ article (Free PDF)
New
York Times story
Intensified Early Treatment of Subclinical Diabetes: No Benefit at 5 Years
Longer follow-up might reveal benefit.
Clinicians
often diagnose type 2 diabetes by screening asymptomatic patients, but how intensively patients should be managed at this
early stage of disease is unclear.
Researchers in the U.K., Denmark, and the Netherlands randomized 343 primary care practices to provide either routine care or intensive
multifactorial treatment to 3057 patients with early diabetes that was diagnosed through routine screening. Physicians and
nurses in the intensive intervention received education on targets, algorithms, and lifestyle advice for managing hyperglycemia,
blood pressure, and lipids; in some areas, patients also met periodically with diabetes nurses.
After
a mean follow-up of 5.3 years, mean declines in levels of glycosylated hemoglobin (HbA1c), total and LDL cholesterol,
and blood pressure were slightly but significantly greater in patients in the intensive treatment practices than in those
receiving routine care. The incidence of the primary composite endpoint (cardiovascular death, nonfatal myocardial infarction
or stroke, or revascularization), each of its components, and all-cause death was lower in the intensive treatment group.
However, none of these differences in clinical outcomes reached significance (hazard ratio for composite endpoint, 0.83; P=0.12).
Griffin SJ et al. Effect of
early intensive multifactorial therapy on 5-year cardiovascular outcomes in individuals with type 2 diabetes detected by screening
(ADDITION-Europe): A cluster-randomised trial.Lancet 2011 Jul 9;
378:156. (http://dx.doi.org/10.1016/S0140-6736(11)60698-3)
Medline abstract (Free)
Preiss
D and Sattar N. The case for diabetes screening: ADDITION-Europe. Lancet 2011 Jul 9; 378:106. (http://dx.doi.org/10.1016/S0140-6736(11)60819-2)
Medline abstract (Free)
Use of NSAIDs and COX-2 Inhibitors Raises Risk
for AF
Risk for atrial fibrillation
was especially elevated among new users of nonsteroidal anti-inflammatory drugs and cyclooxygenase-2 inhibitors.
Use of nonselective nonsteroidal anti-inflammatory drugs (NSAIDs) or selective
cyclooxygenase (COX)-2 inhibitors has been associated with elevated risk for chronic atrial fibrillation (Arch Intern Med 2010; 170:1450). In this population-based case-control study from Denmark, investigators assessed risk for atrial fibrillation (AF) or flutter associated with these
drugs.
Nearly 33,000 patients (median age, 75) with first diagnoses of AF were matched with
326,000 age- and sex-matched controls. After adjustments for multiple variables including AF risk factors, NSAID or COX-2
inhibitor use was associated with significantly elevated risk for AF (incident rate ratios, 1.2 and 1.3 for current use of
NSAIDs and COX-2 inhibitors, respectively, and 1.5 and 1.7 for new use of NSAIDs and COX-2 inhibitors, respectively). Results
were similar for individual NSAIDs and COX-2 inhibitors.
Comment: In this study, NSAIDs and COX-2 inhibitors were associated with elevated risk for AF, especially among new users. As
an editorialist noted, these findings have important public health implications because these drugs are used widely and because
AF prevalence increases with age. Although the results could be influenced by confounding (e.g., the investigators lacked
body-mass index data; obesity is strongly associated with arthritis — a common indication for these drugs — and
a risk factor for AF), the findings are plausible: These drugs can exacerbate hypertension and heart failure and, therefore,
might precipitate AF or flutter.
Journal Watch General Medicine July 26, 2011
Magnesium
deficiency could affect cardiovascular function
Magnesium is one of the most essential minerals
in the human body. It is involved in a multitude of biochemical reactions and supports cardiovascular function. In particular,
it is responsible for regulating blood pressure as well as pacing heart rhythm.
Because magnesium is plentiful in Western diets, it seems unlikely that deficiencies
would be caused by insufficient dietary intake. Therefore, investigators in Berlin sought out alternative mechanisms to explain
its occurrence, including genetic factors. When a depletion in the mineral does occur, it most commonly manifests itself as
fatigue and muscle weakness when symptoms first appear, and may escalate to life-threatening
events such as seizures or disturbances in heart rhythm.
The study conducted at the Charite Universitatsmedizin
in Berlin, Germany has provided evidence that such deficiencies may be the result of a genetic mutation. When altered, the
gene called Cnnm2 may directly affect the ability of a protein to attach to intestinal and kidney membranes in order to allow
magnesium to be absorbed into the blood stream.
If the blood level of magnesium falls, less of it reaches the heart.
The heart rhythm may be detrimentally affected by lowered levels of the mineral in two ways - the altered heartbeat may undermine
its main function of pumping blood throughout the body, and the quality of blood could be compromised with lower nutrient
content.
Milk and soy protein may help patients lower blood pressure
Physicians who prefer to recommend lifestyle changes to
improve conditions like high blood pressure may want to take note of a new study that was recently published in Circulation:
Journal of the American Heart Association.
Researchers at Tulane University School of Public Health and Tropical
Medicine found in a randomized, controlled study that individuals who were given a pill containing simple carbohydrates were
less successful at lowering their blood pressure when compared to participants who were given soy or milk protein pills.
"Some previous observational research on eating carbohydrates inconsistently suggested that a high carbohydrate
diet might help reduce blood pressure," said lead researcher Jiang He, M.D., Ph.D. "In contrast, our clinical trial
directly compares soy protein with milk protein on blood pressure, and shows they both lower blood pressure better than carbohydrates."
Participants in the study were given 40 grams daily of either milk or soy protein for eight weeks. The supplements
were shown to lower systolic blood pressure by 2 mmHg, which researchers noted may result in 6 percent fewer deaths from stroke,
a 4 percent reduction in deaths stemming from cardiovascular complications.
Authors of the study noted that the
protein supplements had no significant effect on diastolic blood pressure levels.
Stress cardiomyopathy may affect more demographics than
previously thought
A team of researchers at the University of Leipzig in Germany conducted
a study to better understand the risk factors that may contribute to stress cardiomyopathy (SC).
Their results,
published in the most recent issue of the Journal of the American Medical Association, revealed that more patients may be
affected by the condition than previously reported.
While the medical community has generally associated SC with
postmenopausal women, the team of scientists found that an estimated 11 percent of individuals with the condition are men
and 8 percent are younger than 50, based on a study of 256 patients.
Additionally, it has traditionally been thought
that the vast majority of SC is induced by a stressful event, but within the study's population, just two-thirds had reported
a preceding stressor.
The researchers also found that cardiovascular magnetic resonance imaging may be an accurate
diagnostic tool for SC.
"The combination of typical regional wall motion abnormalities, the presence of reversible
myocardial injury and the absence of significant irreversible tissue injury may serve as a very useful set of diagnostic criteria
and should be prospectively tested," study authors said.
Changes in blood pressure may be relative to age
In a study of 30,372 individuals aged 7 to 80, a team of
researchers from the University College London found that increases and decreases in blood pressure may be related to a patient's
age.
The scientists found that blood pressure rises rapidly throughout adolescence, makes a slower incline
in early adulthood, rises slightly more in middle age, then increases once more in late life before it begins to decline.
"Whilst our study is unable to identify the key determinants of age-related increases in [blood pressure], further
research should try to understand which factors affect this trajectory and when in the life course such factors exhibit most
influence," said study authors.
The study also revealed that, on average, the working population has lower
blood pressure than the general population. The correlation supported the idea that a lower body mass index and higher socioeconomic
status contributed to lower blood pressure levels.
While women in early adulthood tended to have lower levels when
compared to men, blood pressure measurements leveled out later in life, possibly due to physical changes during menopause.
Declining Kidney Function Linked to Higher
AF Risk
In combination with albuminuria,
chronic kidney disease predicted atrial fibrillation.
Alonso A et al. Circulation 2011 Jun 28; 123:2946
Group Therapy After Weight Loss Helps Maintain
Improvements in Obstructive Sleep Apnea
At 1 year, half of patients
no longer required continuous positive airway pressure.
Children: Stay Asleep and Stay Lean
In the first longitudinal study
to measure sleep objectively, reduced sleep duration during early childhood increased risk for becoming overweight.
Carter
PJ et al. BMJ 2011
May 26; 342:d2712
Cappuccio FP and Miller MA. BMJ 2011
May 26; 342:d3306
What's the new -- and independent -- predictor for heart disease?
These results
confirm previous associations between preβ-1 HDL and CHD in a large well-characterized clinical cohort. Also, this is
the first study in which preβ-1 HDL was identified as a novel and independent predictor of myocardial infarction above and beyond traditional coronary heart disease risk factors. The American Journal of Cardiology (8/1/2011)
Aspirin: Sometimes a wonder drug
This updated meta-analysis of randomized controlled
trials found that aspirin prevents deaths, myocardial infarction and ischemic stroke, but increases hemorrhagic stroke and
major bleeding when used in the primary prevention of cardiovascular disease. The American Journal of Medicine (7/2011)
Discontinuing Low-Dose Aspirin After Cardiovascular Events Adds Risk, Study Finds
Patients with cardiovascular disease who stop taking daily
low-dose aspirin show an increased risk for nonfatal MI,
according to a nested case-control study in BMJ.
Researchers
followed a U.K. cohort of some 40,000 patients who'd been prescribed aspirin for secondary prevention of cardio- or cerebrovascular
events. Cases were patients who had the combined outcome of nonfatal MI or death from coronary heart disease during roughly
3 years' follow-up. Controls were randomly selected from the cohort.
When patients
were evaluated according to their adherence to aspirin, those who had recently discontinued use were at higher risk than current
users both for the combined outcome (rate ratio, 1.43) and its nonfatal MI component (RR, 1.63), but not for coronary death
alone.
Editorialists say that patients on aspirin for secondary prevention "should be
advised that unless severe bleeding ensues or an informed colleague explicitly says so, aspirin should never be discontinued."
BMJ article (Free
Study:
Stopping aspirin regimen raises heart attack risk
Patients with heart disease who stopped taking low-dose prescription
aspirin within one to six months were 63% more likely to suffer a nonfatal heart attack than those who stayed on the medication,
a study in the British Medical Journal found. The findings underscore the importance of taking daily doses of aspirin to prevent
future incidences of heart attack, experts said. Los Angeles Times/Booster Shots blog (7/21), WBAY-TV (Green Bay, Wis.) (7/22
Good news for familial hypercholesterolemia patientsThis study concluded
that advances in drug therapy over the last three decades has led to substantial reductions in LDL levels and appears to diminish
cardiovascular risk in familial hypercholesterolemia patients. The American Journal of Cardiology (7/15/2011)
Cervical cancer: When screening fails, and why
Half of the women with cervical cancer were never
screened because of the limited target age range or nonattendance. Twenty-one percent had
a normal smear within five years preceding the diagnosis, caused by interpretation and/or sampling errors. American Journal of Obstetrics & Gynecology (7/2011)
Persistent organic pollutant raises arthritis risk in study
People
whose blood exhibited the highest levels of perfluorooctanoate (PFOA-Teflon component) -- an organic pollutant used in nonstick and stain-resistant coatings -- had
a 40% higher risk of arthritis compared with those who had lower levels, according to a
study in the American Journal of Epidemiology. Meanwhile, those who had the highest levels of perfluorooctane
sulfonate, another chemical used in the coatings, had a 25% lower risk of arthritis than those with the lowest levels,
which researchers said could be due to some inflammation-reducing effect of the chemical. Reuters(7/13)
Obesity vs. cardiorespiratory fitness
These data suggest that obesity may offset
the benefits of physical activity on achieved cardiorespiratory fitness, even among a healthy
population of men and women. The American Journal of Cardiology(7/1/2011
Salicylic Acid Is as Effective as Cryotherapy
for Plantar Warts
And costs were lower for home-administered
salicylic acid treatment.
Cockayne S et al. BMJ 2011 Jun 7; 342:d3271
Guidelines for Delirium Prevention in At-Risk Adults Free!
U.K.
national guidelines provide 13 specific recommendations for a multidisciplinary intervention.
O'Mahony
R et al. Ann Intern Med 2011
Jun 7; 154:746
Risk for Sudden Cardiac Death in Women
Most risk was attributed to four lifestyle factors.
Chiuve
SE et al. JAMA 2011
Jul 6; 306:62
Triage for Transient Ischemic Attack in
the Emergency Department
Outcomes after TIA were comparable for people managed as outpatients and those managed
as inpatients, after triage with the ABCD2 risk-stratification
score.
Olivot J-M et al. Stroke 2011 Jul 42:1839
Triglycerides and Cardiovascular Disease:
The Experts Speak Free!
Experts redefine
an optimal triglyceride level and stress that lifestyle changes are required to reach it.
Miller
M et al. Circulation 2011
May 24; 123:2292
Don't Miss the New AHA Recommendations
on Triglycerides Free!
A new scientific statement raises the threshold for pharmacologic treatment
of hypertriglyceridemia.
Multifaceted Podiatry
Treatment of Foot Pain Prevents Falls in Elders
Intervention patients received appropriate footwear and
a home-based foot and ankle exercise program.
Among elders, foot problems are associated
with falling, which is a major risk factor for fracture. In this randomized controlled trial, Australian investigators compared
the effectiveness of a multifaceted podiatry intervention versus routine podiatric care in preventing falls in 305 community-dwelling
elders (mean age, 74; 69% women) who had chronic foot pain, were receiving podiatric care, and were at elevated risk for falls.
Both control and intervention
groups continued with the podiatric care they were currently receiving. The intervention group also received a multifaceted
treatment package consisting of prefabricated full-length foot orthotics, advice on and provision of appropriate footwear,
a home-based foot and ankle exercise program, and education in fall prevention. The control group received podiatric care
only. At 1-year follow-up, number of falls was significantly lower in the intervention group than in the control group (103
vs. 161 falls). The intervention group experienced one fracture, and the control group suffered seven fractures — a
not-quite-significant result (P=0.07) that likely reflected an underpowered study.
Original article
Medline abstract (Free)
Low Dietary Calcium Intake Raises Risk for Fracture and Osteoporosis
During 19 years, first fracture of any type was significantly more common among
women with low daily dietary calcium intake ( 750 mg).
Observational studies and randomized trials of dietary or supplemental calcium to prevent
fractures have yielded inconsistent results. In this prospective observational study, investigators determined the associations
between dietary calcium intake and risk for any fracture among a population-based cohort of 61,000 Swedish women; risk for
osteoporosis was evaluated in a randomly selected subcohort of 5000 women.
During a median 19-year
follow-up, 24% of women experienced first fractures of any type, 6% suffered first hip fractures, and 20% developed osteoporosis.
After adjustment for multiple variables, risk for first fracture of any type was significantly higher among women in the lowest
dietary calcium–intake quintile ( 750 mg/day; hazard ratio, 1.2) than among women in the third (middle) quintile (882–996 mg/day).
Similar results for the lowest versus the middle quintile were found for first hip fracture (HR, 1.3) and osteoporosis (HR,
1.5). Low vitamin D intake was associated with excess fracture risk. In contrast, women in the middle and highest (>1137
mg/day) quintiles had similar risks for fracture of any type and similar risks for osteoporosis, but those in the highest
quintile exhibited excess risk for hip fracture (HR, 1.2). Of note, results were similar when total calcium intake (i.e.,
including supplements) instead of dietary calcium intake was evaluated.
Warensjö E et al. Dietary calcium intake and
risk of fracture and osteoporosis: Prospective longitudinal cohort study. BMJ 2011 May 24; 342:d1473. (http://dx.doi.org/10.1136/bmj.d1473)
Original article
Medline abstract (Free)
Inactivity Increases Women's Risk for Thromboembolism
Time spent sitting during a typical day, as a proxy for physical inactivity,
is associated with a woman's risk for idiopathic pulmonary embolism, according to Nurses' Health Study data reported
in BMJ.
Nearly 70,000 women reported
their daily sitting times (as well as measures of physical activity) in the late 1980s. These were compared with reports of
idiopathic pulmonary embolism over the ensuing 18 years of follow-up. Those subjects reporting the most hours per day sitting
were over twice as likely as those with the least seated time to experience a pulmonary embolism (hazard ratio after multivariable
adjustment, 2.34). On the other hand, there was no association between measures of physical activity (walking, running, etc.)
and embolism risk.
Editorialists point out the relatively small absolute risk — roughly
7 additional cases per 10,000 person-years in the most sedentary group — a risk only slightly higher than that observed
among oral contraceptive users.
BMJ article (Free PDF)
Measuring Blood Pressure: Once Is Not Enough
The optimal number of readings
was four or five.
Although patients
often use home blood pressure (BP) monitors, hypertension treatment decisions generally are based on BP measurements obtained
in our offices. One goal of this study was to determine the optimal setting for, and optimal number of, BP measurements for
clinical decision making. Researchers compared systolic BP measurements obtained repeatedly during 18 months for 444 patients
(92% men) at a Veterans Affairs medical center; readings were obtained concurrently in three ways: during routine outpatient
clinic visits, from electronic home monitors, and as part of a research protocol (obtained by research staff) at 6-month intervals.
Systolic BP was deemed controlled if clinic or research-based readings were <140 mm Hg a nd if home-based readings were
<135 mm Hg.
The proportion of patients whose systolic BP was identified as controlled
in the first 30 days varied by measurement type: 28% for clinic readings, 47% for home readings, and 68% for research-based
readings. Regardless of the setting, averaging the measurements from multiple readings decreased within-patient variability;
the optimal number of readings was approximately four to five. The intervals between
readings differed for each group: three times weekly for home monitoring readings, two readings
every 6 months for the research readings, and variable intervals for outpatient routine clinic visits.
Powers BJ et al. Measuring blood pressure for decision making and quality reporting: Where and how many measures? Ann Intern Med 2011 Jun
21; 154:781.
Medline abstract (Free)
