Exercise for Cardiovascular Disease Prevention and Treatment From Molecular to Clinical, Part 1

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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...

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