Tuesday, December 1, 2015

SPRINT trial redefines blood pressure targets


More than 70 million people in the United States suffer from hypertension – which presently is defined by a systolic blood pressure of higher than 140 mm Hg and a diastolic of higher than 90 mm Hg.  A landmark study called SPRINT (Systolic Blood Pressure Intervention Trial) challenges the accepted guidelines of optimum level for systolic blood pressure and provided information about benefits and shortcomings of intensive pharmacotherapy. The study was published in NEJM was interrupted nearly two years early, when it became apparent that lower blood pressure for most people over 50 prevented heart problems and deaths.

In the SPRINT trial, 14,692 patients were assessed for eligibility, and 9361 individuals with a systolic blood pressure of 130 mm Hg or higher and an increased cardiovascular risk, but without diabetes, were randomly assigned in two groups; a systolic blood-pressure target group of less than 120 mm Hg (intensive treatment) or a target group of less than 140 mm Hg (standard treatment).

The primary outcomes were myocardial infarction, other acute coronary syndromes, stroke, heart failure, or death from cardiovascular causes.
At 1 year, the mean systolic blood pressure was 121.4 mm Hg in the intensive-treatment group and 136.2 mm Hg in the standard-treatment group. The mean number of blood-pressure medications was 2.8 in the intensive-treatment group and 1.8 in the standard-treatment group.  The intervention was stopped early after a median follow-up of 3.26 years owing to a significantly lower rate of the primary composite outcome in the intensive-treatment group than in the standard-treatment group (1.65% per year vs. 2.19% per year; hazard ratio with intensive treatment, 0.75; 95% confidence interval [CI], 0.64 to 0.89; P<0.001). All-cause mortality was also significantly lower in the intensive-treatment group (hazard ratio, 0.73; 95% CI, 0.60 to 0.90; P=0.003).
Investigators found that there were 27% fewer deaths (155 compared with 210) and 38% fewer cases of heart failure (62 compared with 100) among patients who achieved the systolic pressure target of 120 mm Hg than among those who achieved the current 140 mm Hg target.
The lower relative risk of major cardiovascular events observed across subgroups defined according to age, sex, race, medical history, and baseline blood pressure among patients who achieved the systolic pressure target of 120 mm Hg in comparison to those who achieved the currently recommended level of 140 mm Hg.
Rates of serious adverse events of hypotension, syncope were 67% and 33% higher in the intensive therapy group.   Electrolyte abnormalities, and acute kidney failure were noted but injuries due to falls surprisingly were not more common, as had been feared among the elderly in the intensive-treatment group.

The research indicated that among patients over 50 at high risk for cardiovascular events who are not diabetics, targeting a systolic blood pressure below the current guidelines of 140 or 150 mm Hg to less than 120 mm Hg, prevented heart disease and strokes and thus save lives.


DOI: 10.1056/NEJMoa1511939

Sunday, November 1, 2015

Breast Cancer Screening for Women at Average Risk



Breast cancer is a leading cause of mortality among US women.  About 200,000 women are being diagnosed every year in the US with breast cancer and 40,000 women die from the disease.
Despite the interest and research on breast cancer screening, there is uncertainty about mammography’s benefits versus potential harms from false positives and overdiagnosis.  Thus recommendations on the frequency of its use are wide-ranging.  Different countries and professional societies have guidelines recommending from annual to biennial to triennial or no screening at all.   

In 2003, the American Cancer Society (ACS) recommended annual mammography screening for all women starting at age 40 years and continuing as long as a woman remained in good health.  The ACS also recommended clinical breast examination (CBE) periodically for women in their 20s and 30s and annually for women 40 years and older.
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The ACS has revised its guidelines regarding when and how often women at average risk should receive screenings for breast cancer.

The ACS commissioned a systematic evidence review in 2015 of the breast cancer screening literature and a supplemental analysis of mammography registry data to address questions related to the screening interval.

 Formulation of recommendations was based on the quality of the evidence and judgment about the balance of benefits and harms such as biopsies resulting from false positive mammograms.

Screening mammography in women aged 40 to 69 years is associated with a reduction in breast cancer deaths to as much as 30 percent, and inferential evidence supports breast cancer screening for women 70 years and older that are in good health.  Evidence does not support routine clinical breast examination as a screening method for women at average risk.

Oeffinger et al review and analysis are described in their paper in JAMA and form the basis of the new ACS recommendations that are:

·      - Women with an average risk of breast cancer should undergo regular screening mammography starting at age 45 years (strong recommendation).

·      - Women aged 45 to 54 years should be screened annually (qualified recommendation).

·     -  Women 55 years and older should transition to biennial screening (strong recommendation).

·     -  Women should have the opportunity to begin annual screening between the ages of 40 and 44 years (qualified recommendation).

·     -  Women should continue screening mammography as long as their overall health is good and they have a life expectancy of 10 years or longer (qualified recommendation).


The ACS does not recommend clinical breast examination for breast cancer screening among average-risk women at any age (qualified recommendation).

These updated ACS recommendations bring it closer to the draft guidelines released on April 20, 2015, by the U.S. Preventive Services Task Force (USPSTF) for breast cancer screening which are:


·      For women at average risk for breast cancer, most of the benefit of mammography will result from biennial screening during ages 50 to 74 years.

·      Of all age groups, women ages 60 to 69 years are most likely to avoid a breast cancer death through mammography screening.

·      Screening mammography in women ages 40 to 49 years may reduce the risk of dying of breast cancer, but the number of deaths averted is much smaller than in older women and the number of false-positive tests and unnecessary biopsies are larger.

·      Women with a parent, sibling, or child with breast cancer may benefit more than average-risk women from beginning screening between the ages of 40 and 49 years.


·      The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of screening mammography in women age 75 years and older.

·      The USPSTF concludes that the current evidence is insufficient to assess the benefits and harms of tomosynthesis (3-D mammography) as a screening modality for breast cancer.

The ACS and USPSTF guidelines are now more consistent and state that the decision to start screening mammography prior to age 50 years should be an individual one. Both guidelines agree that for average-risk women younger than 45 years, the harms from false positive screening mammograms outweigh the benefits. For women older than 55 years, biennial mammography is likely to provide the most benefits while limiting the harms. The new ACS recommendation to stop screening for older women with life expectancies of less than 10 years is consistent with the emphasis on functional versus chronologic age.  ACS is also recommending ending physical for screening purposes by doctors entirely.

These recommendations do not apply to women age 40 years and older who are at high risk because pre-existing breast cancer or a previously diagnosed high-risk breast lesion and who are known to have underlying genetic mutation (such as a BRCA mutation or other familial breast cancer syndrome) or a history of chest radiation at a young age.  Women at high risk for developing breast cancer will require a more personalized screening than the vast majority of women who are at average risk.

There will be many professional societies and well meaning doctors who will disagree with the new guidelines from ACS and USPSTF but until and when a well designed prospective randomized study provides findings that differ with the above mentioned recommendations they will likely stand.

Sunday, October 4, 2015

Mediterranean Diet may Reduce Breast Cancer Risk - The PREDIMED Trial

 

A paper by Toledo et al published in JAMAInternal Medicine suggests that women could reduce their breast cancer risk by following a version of the Mediterranean diet that goes heavy on extra virgin olive oil.

The study was conducted within the frame of PREDIMED trial a 1:1:1 randomized, single-blind, controlled field trial from 2003 to 2009, on 4282 women aged 60 to 80 years who were at high cardiovascular disease risk.

Participants were randomly allocated to a Mediterranean diet (MeDiet) that was supplemented with extra-virgin olive oil (EVOO), a Mediterranean diet supplemented with mixed nuts, or a control diet (advice to reduce dietary fat).

After a median follow-up of 4.8 years, they identified 35 confirmed cases of breast cancer.  The observed rates (per 1000 person-years) were 1.1 for the Mediterranean diet with extra-virgin olive oil group, 1.8 for the Mediterranean diet with nuts group, and 2.9 for the control group. The multivariable-adjusted hazard ratios versus the control group were 0.32 (95% CI, 0.13-0.79) for the Mediterranean diet with extra-virgin olive oil group and 0.59 (95% CI, 0.26-1.35) for the Mediterranean diet with nuts group. When both MeDiet groups were merged together, they observed a 51% relative risk reduction (95% CI, 0.25-0.94). When they excluded women who were diagnosed with breast cancer during the first year after enrollment, the results remained unchanged.  The information that was collected in this study was on invasive breast cancers only therefore noninvasive tumors such as DCIS, in situ cancers, were not included or analyzed in this trial.

The data from the PREDIMED trial, suggest a significant inverse association between consumption of a MeDiet supplemented with EVOO and breast cancer incidence. A high consumption of EVOO (≥15% of total energy intake) seems to be instrumental in obtaining this significant protection. A non-significant risk reduction was observed with the MeDiet supplemented with nuts.

In a different trial, the Lyon Diet Heart Study, which was also a randomized trial, a protective effect of a Mediterranean-type diet against overall cancer incidence was observed, supporting the hypothesis of an anticancer effect of the MeDiet.

The low rate of breast cancer among women in the PREDIMED trial should not be surprising. If the MeDiet is actually protective against breast cancer, a low incidence is to be expected in a study with these characteristics, especially when overall adherence to such diet was good already at baseline. 

Several biological mechanisms could explain the anti-carcinogenic properties of EVOO. All types of olive oil provide a high supply of monounsaturated fatty acids, mainly oleic acid, as well as squalene, but EVOO also contains additional biologically active compounds as polyphenols.
These compounds are known to have a likely role in breast cancer prevention due to inhibition of tumor growth and proliferation, migration, and invasiveness of breast cancer cells in both in vitro or in vivo breast cancer models.  Olive oil has been associated with increased apoptosis of cultured breast cancer cells. It has also been reported to reduce intracellular reactive oxygen processes and to prevent oxidative DNA damage in both human breast epithelial cells and human breast cancer cells.

The authors conclude that the findings of their trial suggest a beneficial effect of the Mediterranean diet supplemented with extra-virgin olive oil as a primary prevention of breast cancer.  The authors also state that their findings need to be confirmed with longer-term and larger studies, as breast cancer in addition to being the most prevalent cancer in women worldwide, with 1.7 million new cases diagnosed in 2012 while its incidence is has increased by 20% due to growth and aging of the population.


JAMA Intern Med. published online September 14, 2015.


Tuesday, September 1, 2015

Physical Activity Promotes Higher Cognition in Older Adults


Burzynska et al from the Lifelong Brain and Cognition Lab at the University of Illinois at Urbana report in an article at PLoS One that by looking at functional and structural MRI data found that higher cardiorespiratory fitness (CRF) and physical activity (PA) in old age were associated with greater brain structural and functional integrity, and higher cognitive functioning.

As we age, the physical make up of our brains changes. This includes changes in neural processing in grey matter, but also in the deterioration of structural connections within, which allow communication between distinct brain regions, so that the brain is able to work as a well-wired interconnected network. 

In recent years, researchers have observed that variability in the blood oxygenation as determined by the signal obtained in the BOLD sequence from fMRIs is dependent on functional integrity in certain regions of the brain and is linked to younger age and better cognitive performance..

The researchers collected resting-state fMRI and diffusion images as well as well-normed laboratory measures of fluid intelligence, perceptual speed, episodic memory, and vocabulary from 104 healthy participants (60–80 years).  Because some participants did not complete all tasks in the cognitive battery, a final sample of 91 aging non-demented participants was included in their study.

They also measured CRF as oxygen consumption during a maximal exercise test and measured PA in those healthy but low active older adults with an accelerometer that was worn for 7 days. They modeled the relationships between CRF, PA, and brain functional integrity using multivariate partial least squares analysis. 

As an index of functional brain integrity they used moment-to-moment variability in the blood oxygenation level-dependent signal (SDBOLD), known to be associated with better cognitive functioning. 

The researchers found that older adults who engaged more in light or moderate-to-vigorous physical activities had greater SDBOLD in brain regions such as precuneus, hippocampus, medial and lateral prefrontal, and temporal cortices that play a role in integrating segregated functional domains in the brain.

Their findings suggest that engaging in higher intensity physical activity may have protective effects on neural processing in aging. Finally, they demonstrated that older adults with greater overall white matter microstructure were those in whom their cardiovascular and respiratory systems were functioning optimally and they engaged in physical activities. They concluded that greater blood oxygenation as determined by SDBOLD is a promising correlate of functional brain health and may reflect more flexible or adaptive information processing in older adults. 

PLoS One. 2015 Aug 5;10(8):e0134819

Saturday, August 1, 2015

Risks associated with non-steroidal anti-inflammatory drugs (NSAIDs)



On July 14, 2015 the Food and Drug Administration issued a warning that plans on asking manufacturers of non-steroidal anti-inflammatory drugs (NSAIDs) to change labels to reflect evidence of increased risk of heart attacks and strokes. 

Most NSAIDs inhibit the activity of cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2), and thereby, the synthesis of prostaglandins and thromboxanes.  It is thought that inhibiting COX-2 leads to the anti-inflammatory, analgesic and antipyretic effects and that those NSAIDs that inhibit COX-1, particularly aspirin, may cause gastrointestinal bleeding and ulcers. 

Non-steroidal anti-inflammatory drugs are widely used all over the world for their analgesic and antipyretic qualities and include Motrin IB, Aleve and Celebrex but not aspirin.  In 2001, NSAIDs accounted for 70 million prescriptions and 30 billion over-the-counter doses annually in the United States.

Experts suggest that the warning reflected new evidence that there was risk even in small amounts and that everyone taking them should use them sparingly and for brief periods. 

The FDA said that the drugs increased the risk of a heart attack and/or stroke soon after patients first started taking them, and that while the risk was higher for people with heart disease, it occurs even for people who had never had heart problems.

A meta-analysis of 280 trials of NSAIDs versus placebo (124 513 participants, 68 342 person-years) and 474 trials of one NSAID versus another NSAID (229 296 participants, 165 456 person-years) was published at Lancet in 2013. 

Major vascular events were increased by about a third by a coxib or diclofenac, chiefly due to an increase in major coronary events.  Ibuprofen also significantly increased major coronary events, but not major vascular events
Compared with placebo, of 1000 patients allocated to a coxib or diclofenac for a year, three more had major vascular events, one of which was fatal. Naproxen did not significantly increase major vascular events. 

Vascular death increased significantly by coxibs and diclofenac, non-significantly by ibuprofen but not by naproxen. The proportional effects on major vascular events were independent of baseline characteristics, including vascular risk. 

Heart failure risk was roughly doubled by all NSAIDs. All NSAID regimens increased upper gastrointestinal complications.

The data from these randomized trials suggest that vascular risks of high-dose diclofenac (Voltaren), and possibly ibuprofen (Advil, Motrin), are comparable to coxibs (Celebrex), whereas high-dose naproxen (Aleve) is associated with less vascular risk than other NSAIDs. 

A conclusive answer could come from a large randomized trial, called Precision, that is comparing the rate of heart problems among patients with high cardiovascular risk for ibuprofen (Motrin IB), naproxen (Aleve) and celecoxib (Celebrex).

Patients who use over-the-counter medications, which have the lowest doses, should be aware that they probably increase their risk of a cardiovascular event by about 10 percent. Low-dose prescription medications were likely to increase the risk by about 20 percent and higher-level dose prescription medications by about 50 percent with significant variability in each estimate.