Samir Rafla. top 10 misconceptions about the new prevention guidelines
Top 10 Misconceptions About the New Prevention Guidelines
Michael Blaha, MD, MPH (Disclosure)
Nathan D. Wong, PHD, F.A.C.C. (Disclosure)
February 05, 2014
1. The new lifestyle guidelines do not endorse a particular diet.
While the new lifestyle guidelines do not identify one diet as clearly superior to the
others, the statements clearly endorse a pattern of eating consistent with the
Mediterranean Diet or the DASH diet (Dietary Approaches to Stop Hypertension). Most
importantly, the new guidelines do not endorse the traditional low-fat diet approach.
2. The new lifestyle guidelines do not strongly endorse reduction in sodium intake.
While the new guidelines did not find strong evidence for targeting a particular level of
sodium intake (advice to restrict sodium intake to 2400 mg/day or furthering lowering to
1500 mg/day is described as "desirable" and given level of evidence B [moderate]), the
guidelines strongly recommend an overall reduction in sodium intake (level of evidence
A [strong]). A good goal mentioned in the guidelines is a reduction of 1000 mg/day
which is achievable by most persons and if implemented in a population can have a
dramatic impact on reducing CVD events.
1. The definition of overweight has changed.
The new obesity guidelines did not change the definition of overweight, which
continues to be characterized by a BMI of >25.0 – 29.9 kg/m2. However, in the past
clinicians were advised to begin treating the overweight condition when two or more
comorbidities were additionally present. This requirement has now been reduced to
just one other comorbidity, and this comorbidity can be a concomitantly elevated waist
circumference (indicating visceral adiposity). The cutoff for waist circumference is 40
inches (102 m) or more for a man and 35 (88.9 m) inches or greater for a woman,
identical to the definition of the metabolic syndrome. However, the clinician must
remember that certain ethnic groups have lower cutoff points, for example South and
East Asians. Importantly, the new guidelines recommend regular (at least annually)
assessment of waist circumference in overweight and obese individuals.
2. Select patients are candidates for short courses of intensive behavioral therapy.
On the contrary, the new guidelines recommend more widespread use of intensive
behavioral interventions (ideally consisting of at least 14 sessions within a six month
period) for overweight and obese patients. The best therapy for helping patients lose
weight is behavioral counseling providing advice on how to increase physical activity
and reduce calorie intake for at least six months or longer as part of an on-site, highintensity program with a qualified healthcare provider. This can be accomplished in
either a group session or in individual sessions. The Centers for Medicare & Medicaid
Services (CMS) has indicated that Medicare/Medicaid will reimburse for intensive
behavioral therapy for obesity. For continued weight loss maintenance, the guidelines
recommend a high-intensity weight loss program for at least 1 year.
1. All patients with a 10-year CVD risk of 7.5% or higher, and most patients with 10-year
CVD risk of 5.0% or higher, should be treated with a statin.
The new cholesterol guidelines represent a clear shift away from a treat-to-cholesterol
approach to a treat-to-risk approach. Under the new guidelines, patients with a
calculated 10-year CVD risk of ≥7.5% should be closely considered for statin therapy.
Those with a 10-year CVD risk of ≥5.0% and at least one other additional risk condition
should also be considered for statin therapy. However, in various media outlets it has
been reported that all such patients should be treated with statins. This was not the
intention of the guideline committee. We recommend readers closely examine figure 4
in the cholesterol guidelines, which should be considered the key figure from the
guidelines (not the commonly presented figure 2). Patients meeting the above criteria
should engage in a so-called "risk discussion" with their physicians and make a
personalized decision about starting statins. Many patients who have an elevated risk
based on their age alone will decide (in concert with counseling from the physicians)
not to start a statin. The risk calculator is useful for identifying patients where there is
net clinical benefit for use of a statin; however, it is not the risk calculator, but the
physician who prescribes the statin.
2. There is no longer a role for rechecking lipids values in patients on statin therapy.
While the new guidelines dispensed with lipid targets, there is still a role of rechecking
lipid panels on statins. This is commonly misunderstood. Multiple studies have shown
poor compliance with chronic medications like statins, with poor adherence to therapy
associated with poor outcomes. A lipid panel should be rechecked in 4-12 weeks after
initiating therapy, with additional checks at three to 12 month intervals "as clinically
indicated". The goal of these rechecks to assess for the "anticipated therapeutic
response" to statin therapy. An insufficient therapeutic response (<30% LDL-C
reduction on a moderate intensity or <50% LDL-C reduction on a high intensity statin)
is reason to review barriers the patient may have for achieving adequate adherence, or
if adherence is optimal or tolerability a reason for insufficient response, consideration
of possible non-statin therapies (as discussed below).
3. There is no role for non-statin therapy at any level of LDL-C.
The new guidelines clearly — and appropriately — decreased the role of non-statin
therapy in primary prevention given the lack of proven clinical benefit beyond statin
therapy. The new cholesterol guidelines are for the most part statin guidelines, and
most patients will achieve an LDL <100 mg/dL with appropriately intensive statin
therapy. However, there continues to be a role for add-on non-statin therapy in patients
with presumed familial hyperlipidemia identified by a baseline LDL >190 mg/dL and in
high-risk patients (those with established CVD and in patients with diabetes) who do
not have the anticipated therapeutic response to statins (either statin intolerance or
<50% LDL-C reduction on statins). Clearly the prescription of a non-statin therapy is an
issue where clinical judgment is particularly important and expectations (or lack
thereof) should be clearly discussed with the patient.
1. The new risk algorithm overhauls the Framingham Risk Score, incorporating new risk
markers into the calculation of 10-year CVD risk.
After years of anticipation, and voluminous research in novel areas of risk prediction,
the new risk calculator arrived looking much like the Framingham Risk Score. The
exact same traditional risk factors are included. Obesity, family history, and other novel
biomarkers are not included. What did change? Instead of reliance exclusively on the
Framingham Heart Study, four cohorts encompassing a much larger sample size to
ensure greater precision of estimates were used to derive this new calculator. There is
now a separate equation for African-American patients. In addition, nonfatal and fatal
stroke is added to nonfatal and fatal myocardial infarction to encompass overall
atherosclerotic cardiovascular disease (ASCVD), which is a more clinically relevant
composite outcome than past risk scores which focused on coronary heart disease risk
alone. Finally, the new risk algorithm also allows for calculation of lifetime ASCVD risk,
particularly recommended in younger and middle-aged persons where short-term risk
may be low, but lifetime risk high; this would presumably be a potent motivator for the
patient to improve adherence to lifestyle modifications. It remains to be seen if this new
risk score has improved discrimination and calibration compared to prior risk scores. It
is also unclear if this risk algorithm will lead to more personalized — or via a smaller
intermediate risk group — less personalized risk predictions.
1. Older patients ≥60 years old with treated systolic blood pressure <150 mmHg should
have the intensity of anti-hypertensive therapy reduced.
The new hypertension guidelines have loosened the blood pressure target for older
patients >60 years old to <150/90. However, this does not mean that older adults who
presently have blood pressure <140/90 on multiple agents need a reduction in therapy.
The guidelines specifically include a corollary recommendation that states that "if
pharmacologic treatment for high BP results in lower SBP (eg, <140 mmHg) and
treatment is well tolerated and without adverse effects on health or quality of life,
treatment does not need to be adjusted."
2. The new JNC8 hypertension guidelines represent consensus recommendations, and are
endorsed by major cardiology organizations.
The Joint National Committee 8 (JNC 8) was originally commissioned by the
NIH/NHLBI to produce new hypertension guidelines. However, the NHLBI passed this
responsibility to the AHA and the ACC in 2013. The JNC 8 writing committee did not
wish to wait for AHA/ACC approval, and in fact believe hypertension to be more of a
primary care issue rather than a cardiology issue, and pushed ahead with the recent
publication of their long-awaited guidelines. It is clear that not all members of the JNC8
committee are fully pleased with the final document. A minority report pointed out
concerns regarding the newly recommended higher threshold for BP treatment
initiation, as this could potentially result in poorer blood pressure control overall and
even a possible reversal of the gains in recent decades made in CVD risk reduction.
Moreover, the same week the American Society of Hypertension (ASH) jointly with the
International Society of Hypertension (ISH) released their new guidelines upholding the
prior recommendations for a goal and treatment initiation level of blood pressure in
those <80 years of age of 140/90 mmHg, consistent with the most recent guidelines of
the European Society of Hypertension. The AHA and the ACC have issued a "scientific
advisory" on the treatment of hypertension, and likely will produce their own
hypertension guideline in the future.