CLINICAL
NEWS
American College of Cardiology Extended Learning
Cardiorespiratory Fitness as a Vital Sign
Yes, but how?
I
s weight loss the optimal target for obesityrelated cardiovascular disease risk reduction?
Probably not. That’s based on the life’s work
of several pioneers in this field, including Robert
Ross, PhD, a professor of exercise physiology at the
School of Kinesiology and Health Studies, Queen’s
University, Kingston, Ontario.
Sure, weight loss is associated with substantial
reduction in obesity-related CVD risk and certainly is a desired outcome. However, Dr. Ross and
others have established that increasing physical
activity is associated with marked reduction in
waist circumference, visceral fat, and cardiometabolic risk factors, concurrent with an increase in
cardiorespiratory fitness (CRF)—despite minimal
or no change in body weight.
Consider the 2004 paper Dr. Ross published
with Steven N. Blair, PhD, a professor at the Arnold School of Public Health, University of South
Carolina, Columbia, SC, and another pioneer in
exercise and CRF.1 Cardiorespiratory fitness is associated with lower abdominal fat independent of
body mass index (BMI). Specifically, in comparing
men with high CRF (n = 169) with men showing
low CRF (n = 124), they demonstrated that for a
given BMI, men in the high CRF group had significantly lower waist circumference (p < 0.001) as
well as lower total abdominal tissue (p < 0.001),
visceral adipose tissue (p < 0.001), and abdominal
subcutaneous adipose tissue (p < 0.001) compared
with men in the low CRF group.
Subsequently, a much larger study was performed providing compelling evidence that waste
circumference explains both diabetes and CVD
risk beyond that explained by BMI alone. The
IDEA study (International
Day for Evaluation of Abdominal Obesity) involved 6,407
randomly chosen primary
care physicians in 63 countries, who evaluated 168,159
patients ages 18 to 80 years.2
To listen to the
There was a graded
interview with Robert
increase in the frequency of
Ross, PhD, on the
topic of implementing
CVD and diabetes mellitus
CRF measurement in
with both BMI and waist
clinical practice, visit
circumference but there was a
the CSWN YouTube
channel channel by
stronger relationship for waist
scanning the QR code
circumference than for BMI
below. The interview
across regions for both sexes.
was conducted by
Christopher M.
Shortly thereafter, Ross and
Kramer, MD.
colleagues demonstrated that
waist circumference predicts
diabetes risk beyond BMI and
other commonly measured
cardiometabolic risk factors,
such as smoking, dyslipidemia
and blood pressure.3
26 CardioSource WorldNews
The data are summarized in a paper published
by Dr. Ross and Peter M Janiszewski, MSc.4 Together, the evidence underscored the importance of
waist circumference as a routine measure in clinical
practice that should be a primary treatment target
for strategies designed to reduce obesity-related
CVD risk. Indeed, Dr. Ross and others think that
exercise should be viewed as a cost-effective medication for all patients with or at-risk for CVD.
HOW DO YOU THAT?
It’s not easy—as most clinicians probably try this
approach regularly (usually feeling as if their efforts just don’t work)—but there are suggestions
that Dr. Ross and colleagues promote5 that can be
highly beneficial.
Motivating exercise in the physician office
or clinical environment: If physicians, physical
therapists, dietitians, and other health professionals
all consistently assess and promote physical activity
as a routine component of every clinical encounter,
they note “it is likely that we would start to see
changes in patient self-reported physical activity.”
Think realistically: Dr. Ross noted recently, “The
clinical reality for most in patient care disciplines
is that our patients are mostly sedentary and have
been that way for their entire adult lives. The expectation that they will suddenly become someone
who performs 30 minutes of exercise on most
days of the week is simply unrealistic.
Key to promoting cardiorespiratory fitness in
the clinical setting is the use of a physical activity
vital sign in which every patient’s exercise habits
are assessed and recorded in their medical record.
Those not meeting the guideline-recommended
150 minutes per week of moderate intensity physical activity should be encouraged to increase their
physical activity levels with a proper exercise prescription. According to Dr. Ross: “If you maintain
that 150 minutes of activity most weeks, you will
improve your cardiorespiratory fitness and you
will reduce morbidity and mortality substantially.
They write, “We can improve compliance by
assessing our patient’s barriers to being more active and employing new and evolving technology
like accelerometers and smart phones applications,
along with various websites and programs that
have proven efficacy.”5
Manage realistically: Help patients access and
manage their exercise and physical activity; you
can only manage what you measure. Encourage
patients to keep track of their adherence to exercise and track their daily activity. This can be done
on paper, or increasingly, with a myriad of digital
devices and smart phone applications.
Practice what you preach: “Each and every
health care professional involved with helping
patients manage chronic disease conditions that
may benefit from increased adherence to exercise and physical activity must be aware that our
patients often ask what we do. If we do not adhere
to exercise therapies, then they may be less likely
to themselves,” he emphasized.
According to Dr. Ross, physical inactivity is the
major public health problem of our time. While
obesity is most often publicized, its adverse effects
on health are largely mitigated by engaging in regular physical activity.
Physicians cannot do it alone: Everyone on the
health care team, from the front desk receptionist
to the medical assistant, nursing staff, dietitians,
physical therapists, etc., needs to be on the same
page: actively promoting regular physical activity
as a key to improved health outcomes. Likewise,
the expanded use of technology to track activity
can help support the achievement of step goals.
According to Dr. Ross, ultimately, to succeed,
“we need to leverage all the tools in our toolbox
and continue to investigate and add new tools in
our efforts to help our patients, our families, and
our communities move more.” ■
REFERENCES:
1. Wong SL, Katzmarzyk P, Nichaman MZ, et al. Med Sci
Sports Exerc. 2004;36:286-91.
2. Balkau B, Deanfield JE, Despres JP, et al. Circulation.
2007;116:1942-51.
3. Janiszewski PM, Janssen I, Ross R. Diabetes Care.
2007;30:3105-9.
4. Ross R, Janiszewski PM. Can J Card iol. 2008;24(Suppl
D):25D-31D.
5. Sallis R, Franklin B, Joy L, et al. Prog Cardiovasc Dis.
2015;57:375-86.
Take-aways
• The connection between physical activity and
health has been clearly established, and exercise
should be viewed as a cost-effective medication
for all patients with or at risk for CVD.
• Physicians cannot do it alone but must be joined
by the entire team—from receptionist to all other
staff and associates who meet patients—who
should be on the same page promoting physical
activity.
• The expanded use of technology to track
a patient’s activity can help support the
achievement of step goals.
• Ultimately clinicians will need to leverage all the
tools in their toolbox and continue to investigate
and add new tools so that patients, their families,
and our communities move more.
June 2016