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3 Risk Factors for Cardiovascular Disease
Over 300 risk factors have been identified for CVD. In order to be classified as a
major risk factor, however, an exposure or behaviour must meet three criteria: (1) an
independent association with CVD; (2) a high prevalence in many populations; and
(3) its treatment and control can result in reduced risk. The contribution of individ-
ual risk factors may vary depending on the socioeconomic status of the country and
the prevailing forms of CVD. In Britain, around 80% of CHD events in middle-aged
men are thought to be explained by total cholesterol, blood pressure and cigarette
smoking [ 6 ]. High blood pressure presents a greater risk for ischaemic stroke, while
high cholesterol is a stronger predictor of CHD risk. Herein, we discuss ‘traditional’
and ‘novel’ risk factors because 20–50% of CHD events are not explained by tradi-
tional risk factors [ 6 ].
3.1 Non-modifiable CVD Risk Factors
Risk factors that cannot be modified include age, male gender, and a family history
of premature CVD. Advancing age is one of the most powerful risk factors for
CVD; for example, the risk of stroke doubles every decade past the age of 55 years.
Cardiovascular disease is not inevitable, but age is a surrogate measure of exposure
to all other risk factors. Historically, men experience a higher rate of CVD than
women at a younger age, and prior to menopause women have better cardiovascular
risk profiles than men [ 7 ]. For example, pre-menopausal women demonstrate lower
levels of blood pressure and LDL-C and higher levels of high-density lipoprotein
cholesterol (LDL-C). Given that risk profiles of women and men become similar
following the menopause, the cardio-protective effects of female sex hormones may
partly explain the gender difference in CVD risk. Postmenopausal women appear to
be at a distinct disadvantage because diabetes carries a significantly greater risk of
CVD and systolic hypertension becomes more frequent in older women.
3.2 Physical Inactivity and Other Modifiable CVD Risk
Factors
Some of the major CVD risk factors are modifiable, in that they can be prevented,
treated and controlled. The World Health Organisation highlights seven major mod-
ifiable CVD risk factors, which include raised blood pressure, abnormal blood lip-
ids, tobacco use, physical inactivity, obesity, unhealthy diet, and diabetes mellitus.
Physical inactivity has been defined as an activity level insufficient to meet the
World Health Organisation recommendation of at least 150 min per week of
moderate- intensity aerobic activity, or at least 75 min per week of vigorous- intensity
1 Physical Inactivity and the Economic and Health Burdens Due to Cardiovascular...