The concept of risk factors constitutes a major advance for developing strategies to prevent CVD. The Framingham H e a t Study played a vital role in defining the contribution of risk factors to CAD occurrence in the general population. CAD is almost always caused by atherosclerosis of the coronaq arteries, There are certain factors or characteristics that increase the chance or possibility of getting coronary artery disease. These factors by their presence or association predispose, cause, accelerate and/or aggravate the atherosclerotic process or increase the chance of getting CVD. The term risk factor describes those characteristics found in healthy
individuals, which are independently related to the subsequent occurrence of CAD.Risk factors of CAD &e conventionally classified as causal, conditional or predisposing factors. Causal factors are directly responsible for promoting atherosclerosis. High blood cholesterol is one of them. Conditional factors are associated with an increased risk of CAD but their role in atherogenesis is mostly contributory and not a causal one - for example high'aiglycelide level in the blood.
The predisposing risk factors like age and sex influence CAD by intensifying the action of major causal factors and also affuting the conditional factors.The risk factors can again be classified as major or minor factors. The major factors are those conditions, which even if present singly c~an promote atherosclerosis. On the other hand two or more minor factors are required to exert significant effect on the pathological process.
However from the preventive point of view the important way of classifying thein is to group them as modifiable or non-modifiable factors. Modifiable factors can be controlled or modified by silnple measures whereas non-modifiable risk factors cannot be changed or modified. The non-modifiable factors are the personal characteristics like age, sex, heredity, and family histo~y of early-onset CAD, none of which can be cl~anged. On the other hand h e illodiriable factors are mostly the lifestyles and biochelnical and physiological characteristics, which are runellable to control, modification, elimination and treatment - and so are the main focuses of action in prevention of CAD.
individuals, which are independently related to the subsequent occurrence of CAD.Risk factors of CAD &e conventionally classified as causal, conditional or predisposing factors. Causal factors are directly responsible for promoting atherosclerosis. High blood cholesterol is one of them. Conditional factors are associated with an increased risk of CAD but their role in atherogenesis is mostly contributory and not a causal one - for example high'aiglycelide level in the blood.
The predisposing risk factors like age and sex influence CAD by intensifying the action of major causal factors and also affuting the conditional factors.The risk factors can again be classified as major or minor factors. The major factors are those conditions, which even if present singly c~an promote atherosclerosis. On the other hand two or more minor factors are required to exert significant effect on the pathological process.
However from the preventive point of view the important way of classifying thein is to group them as modifiable or non-modifiable factors. Modifiable factors can be controlled or modified by silnple measures whereas non-modifiable risk factors cannot be changed or modified. The non-modifiable factors are the personal characteristics like age, sex, heredity, and family histo~y of early-onset CAD, none of which can be cl~anged. On the other hand h e illodiriable factors are mostly the lifestyles and biochelnical and physiological characteristics, which are runellable to control, modification, elimination and treatment - and so are the main focuses of action in prevention of CAD.
Personal Risk Factors
The personal risk factors are the factors that are specific and chmacteristic lor a particular individual and are non-modifiable in nat~~re.Age, gender, and faillily history are the variables in the personal segment.
Age
Age is a risk factor in the sense that the atherosclerotic process, which starts early in life, progresses over the years as a functioil of time. The total plaque burden and incidence of coronary artery disease (and also of stroke) increases wit11 age,becoming more prevalent in the elderly age groups. In men aged 30-39 years,ninety-eight per cent have the 10-year risk of CAD less than 10 per cent. But this rises to more than 20 per cent risk in 10 years in almost half of the men in the agegroup of 70-79 years. Similarly in women, while none have :I I0 ye:ll- rislc of 10 per cent iii the age group below 40, about 22 per cent will have a risk of 10 per cent or more in the age group 70-79 years.
Gender
In every age group, men sul'fel- more than wornen from athcrosclerosi~ ant1 coronary artery disease; women are to a great extent psotected by the female sex hormones. However, this advantage, nlost pronlinent in reproductive years,diminishes after menopause and women at six111 :und seventh decades have almost the same incidence as their male counlel-patts, Thc recent trend in the increasing incidence of CAD even in premenopausal years may be related to Ihe stressli~l lire situations, rise in smoking habits and use of oral contlaceptives in women. The mortality is also high among wornen al'ler a heart attack. Middlc-aged women who have heart attacks are more likely than men to die withill two years. US I'liysicians studying medical records of 6800 peoplc trcutctl I'oI. heart uctnclcs in hospit:lls in Worcester, Massachusetts, between 1975 and 1995, round that wolllcn uncler 60 were almost 40 per cent more lilcely lo clic tli~ui men of Ihcir own age. The comparative risk for death was highest fi)r younger women, alid tl~ose unclcr 50 had nearly 50 pcr cent more risk of' clyirlg than their male coimterpa~.ts. It is only among the very elderly heart altnck patienls that womcn huvc Inwcr mortality rates. Again, after coronary bypass surgery, wonicn havc as much as clirce linles higher risk of dying cluring or shorlly al'lcr thc surgery, even though their coronary atlierosclerosis may be less extc~lsivc and their hc;ut ~,unlping i~clion may be Ixttcl;as reported by a US study.
Family History
History of corollary artery discasc in closc relatives like parc~~ls or siblings indicates the hcrhdit;~;y predisposilion to tlic coro~iiuy t1isc;lsc. Fiuliily history of CAD or other atherosclerotic vnscul;ir discnsc :I[ ill] early age ( i l l 1ile11 < 55 ycars,in wolnen < 65 years) in I'irst degrcc relatives lihc parcnts tuld sihli~igs i~icreascs the risk of CAD. Sibling CVD uppcars Lo conks more risk than pclrcnt:~l prcmatul.eCVD and represents a more l~scfi~l markel ol' I't11nili;ll vl~lnerahility lo C'VD cvcnts.The true nature of the genetic susccptihility has not ye[ heco I'nlly undcrstoocl, But it ]nay be related to the nggrcgnlio~i 01' Lhc major risk f:~clors liltc tlii~betcs,Hypertension, lipid abnormalities or obesity. C11iItl1.cn bonl to r:ui~ilies with n high prevalence of these risk filcto~.s are also a1 risk for develop~ilcnt of CAI).Includes people with diabetes but not coronary heart disease.
The personal risk factors are the factors that are specific and chmacteristic lor a particular individual and are non-modifiable in nat~~re.Age, gender, and faillily history are the variables in the personal segment.
Age
Age is a risk factor in the sense that the atherosclerotic process, which starts early in life, progresses over the years as a functioil of time. The total plaque burden and incidence of coronary artery disease (and also of stroke) increases wit11 age,becoming more prevalent in the elderly age groups. In men aged 30-39 years,ninety-eight per cent have the 10-year risk of CAD less than 10 per cent. But this rises to more than 20 per cent risk in 10 years in almost half of the men in the agegroup of 70-79 years. Similarly in women, while none have :I I0 ye:ll- rislc of 10 per cent iii the age group below 40, about 22 per cent will have a risk of 10 per cent or more in the age group 70-79 years.
Gender
In every age group, men sul'fel- more than wornen from athcrosclerosi~ ant1 coronary artery disease; women are to a great extent psotected by the female sex hormones. However, this advantage, nlost pronlinent in reproductive years,diminishes after menopause and women at six111 :und seventh decades have almost the same incidence as their male counlel-patts, Thc recent trend in the increasing incidence of CAD even in premenopausal years may be related to Ihe stressli~l lire situations, rise in smoking habits and use of oral contlaceptives in women. The mortality is also high among wornen al'ler a heart attack. Middlc-aged women who have heart attacks are more likely than men to die withill two years. US I'liysicians studying medical records of 6800 peoplc trcutctl I'oI. heart uctnclcs in hospit:lls in Worcester, Massachusetts, between 1975 and 1995, round that wolllcn uncler 60 were almost 40 per cent more lilcely lo clic tli~ui men of Ihcir own age. The comparative risk for death was highest fi)r younger women, alid tl~ose unclcr 50 had nearly 50 pcr cent more risk of' clyirlg than their male coimterpa~.ts. It is only among the very elderly heart altnck patienls that womcn huvc Inwcr mortality rates. Again, after coronary bypass surgery, wonicn havc as much as clirce linles higher risk of dying cluring or shorlly al'lcr thc surgery, even though their coronary atlierosclerosis may be less extc~lsivc and their hc;ut ~,unlping i~clion may be Ixttcl;as reported by a US study.
Family History
History of corollary artery discasc in closc relatives like parc~~ls or siblings indicates the hcrhdit;~;y predisposilion to tlic coro~iiuy t1isc;lsc. Fiuliily history of CAD or other atherosclerotic vnscul;ir discnsc :I[ ill] early age ( i l l 1ile11 < 55 ycars,in wolnen < 65 years) in I'irst degrcc relatives lihc parcnts tuld sihli~igs i~icreascs the risk of CAD. Sibling CVD uppcars Lo conks more risk than pclrcnt:~l prcmatul.eCVD and represents a more l~scfi~l markel ol' I't11nili;ll vl~lnerahility lo C'VD cvcnts.The true nature of the genetic susccptihility has not ye[ heco I'nlly undcrstoocl, But it ]nay be related to the nggrcgnlio~i 01' Lhc major risk f:~clors liltc tlii~betcs,Hypertension, lipid abnormalities or obesity. C11iItl1.cn bonl to r:ui~ilies with n high prevalence of these risk filcto~.s are also a1 risk for develop~ilcnt of CAI).Includes people with diabetes but not coronary heart disease.
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