Special CME Issue - West Virginia State Medical Association

Figure 1.
The 30 year History of Prostate Cancer in West Virginia. The figure shows a significant
reduction in percent relative mortality since 1996.
ADT may induce a significant loss
of skeletal muscle with an increase
in fat mass, a decrease in bone
mineral density with an increased
risk of fracture, 10 reduced upper and
lower body muscle strength, and
impaired physical and functional
musculoskeletal performance. 11
Patients receiving ADT have been
reported to have 24% less muscular
strength, 7% less aerobic fitness, and
20-27% less functional performance
ability in repeated chair rise and
walking tests compared with agematched
controls. 12 Most men who
develop prostate cancer and require
treatment are over the age of 65.
This has led to the concern that may
cause an early onset of sarcopenia,
frailty, and osteoporosis. 13 Men
undergoing ADT are also at an
increased risk of developing insulin
resistance, hyperlipidemia, obesity
and cardiovascular disease. 8,14-15
The above effects contribute to
a loss of independence, further
reducing quality of life.
Clearly, a primary focus for
health care providers should be
addressing preventive measures
of prostate cancer and improving
the quality of life of their patients
with the disease. Since this disease
is so common, it is imperative that
effective interventions be developed
which could modify risk factors and
also lessen the side effects associated
with standard treatment. Exercise/
physical activity has been proposed
to be one such intervention.
A literature review search
for publications was conducted
through the PubMed database
using the search criteria “Exercise
and Prostate Cancer.” Search
results were reviewed for
relevance by the contributing
authors to this manuscript.
Effect of Exercise on
Preventing Prostate Cancer
Evaluation of the epidemiological
evidence regarding the association
between exercise and prostate cancer
development has been difficult as
studies show inconsistent findings.
There have been a few studies
indicating that regular exercise
reduces the risk of developing
prostate cancer, although the
magnitude of this reduction is
reportedly low. Many cancers,
including prostate cancer, have been
associated with being overweight
and obese, and there is growing
evidence linking excessive body fat
to cancer risk. 16 Life-long vigorous
physical activity has clearly been
shown to reduce adiposity and
the chances of developing obesity.
Whether or not the potential inverse
relationship between vigorous
life-long exercise and prostate
cancer risk occurs as a result of a
long-term low body fat percentage
has yet to be fully determined.
Currently there is no definitive
opinion on the degree of impact that
the amount of exercise and physical
activity have on prostate cancer
incidence or progression. A landmark
paper by Giovannucci 17 tried to
answer that very question. The
relationship of physical activity to
prostate cancer incidence, mortality,
and Gleason histologic grade was
assessed. The authors evaluated
the number of cases of incident,
advanced (seminal vesicle invasion,
metastatic, or fatal), fatal, and high
grade prostate cancer in 47,620 US
male health professionals taking part
in the Health Professionals Follow-up
Study. After 14 years of follow-up,
they documented 2892 new cases
of prostate cancer, including 482
advanced cases (280 of which were
fatal). In regards to the overall cases
of prostate cancer, no association
was observed in regards to the level
of activity. Men aged 65 years or
older exhibited the lowest risk in the
highest category of vigorous activity
for advanced and fatal prostate
cancers. Patients with high levels of
physical activity who were diagnosed
with prostate cancer were less
likely to be diagnosed with poorlydifferentiated
cancers (Gleason grade
7 or greater). The authors state that
their findings suggest that regular
THE ART, SCIENCE AND ETHICS OF PREVENTION | Vol. 108 43