Behavioural risk factors
The risk factors for CHD can be understood and predicted by examining an individual’s health beliefs. Psychology’s role is to both understand and attempt to change these behavioural risk factors.
Smoking is estimated to be the cause of one in four deaths from CHD. Smoking more than 20 cigarettes a day increases the risk of CHD in middle-age threefold. Giving up smoking can halve the risk of another heart attack in those who have already had one.
Diet and exercise (especially cholesterol levels) have also been implicated in CHD. It has been suggested that the 20 per cent of a population with the highest cholesterol levels are three times more likely to die of heart disease than the 20 per cent with the lowest levels. We can reduce cholesterol by cutting down total fats and saturated fats in our diet, and increasing polyunsaturated fats and dietary fibre. Other risk factors include excess coffee and alcohol and lack of exercise.
High blood pressure is another risk factor – the higher the blood pressure, the greater the risk. Even a small decrease in the average blood pressure of a population could reduce the mortality from CHD by 30 per cent. Blood pressure appears to be related to a multitude of factors, such as genetics, obesity, alcohol intake and salt consumption.
Type A behaviour is probably the most extensively studied risk factor for CHD. Friedman and Rosenman (1959) initially defined type A behaviour as excessive competitiveness, impatience, hostility and vigorous speech. In 1978, using a semi-structured interview, they identified two types of type A behaviour. Type A1 is characterized by vigour, energy, alertness, confidence, loud speaking, rapid speaking, tense clipped speech, impatience, hostility, interrupting,frequent use of the word ‘never’ and frequent use of the word ‘absolutely’. Type A2 was defined as being similar to type A1, but not as extreme, and Type B behaviour was regarded as relaxed (for example, showing no interruptions of others’ speech) and quieter.
Stress has also been extensively studied as a predictor of CHD. In the 1980s Karasek developed a job demand/job control model of stress. He proposed the ‘job demand control hypothesis’, which includes the concept of job strain (see chapter 20). According to Karasek and colleagues (e.g. Karasek & Theorell, 1990), there are two aspects of job strain: i) job demands (which reflect conditions that affect performance) and ii) job autonomy (which reflects theperson’s control over the speed or the nature of decisions made within the job). Karasek’s hypothesis suggests that high job demands and low job autonomy predict CHD. More recently, Karasek developed the hypothesis further to include the concept of social support. This is deemed to be beneficial for CHD, and is defined in terms of emotional support (i.e. trust between co-workers and social cohesion) and instrumental social support (i.e. the provision of extra resources and assistance).
Rehabilitation programmes
Modifying exercise – Most rehabilitation programmes emphasize exercise as the best route to physical recovery, on the assumption that this will in turn promote psychological and social recovery, too. But whether, more generally, these programmes influence risk factors other than exercise (such as smoking, diet and Type A behaviour) is questionable. Modifying type A behaviour – The recurrent coronary prevention project was developed by Friedman et al. (1986) in an attempt to modify type A behaviour. It is based on the following questions: ‘Can type A behaviour be modified?’ and ‘Could such modification reduce the chances of a recurrence?’ The study involved a five-year intervention and1000 participants who had all suffered a heart attack. They were allocated to one of three groups: (i) cardiology counselling, (ii) type A behaviour modification, or (iii) no treatment. Type A behaviour modification involved: discussions of beliefs, values and ways to reduce work demands and increase relaxation, and education about changing the individual’s cognitive framework. At five years, the type A modification group showed a reduced recurrence of heart attacks, suggesting that such intervention programmes may reduce the probability of reinfarction in ‘at risk’ individuals.Modifying general lifestyle factors Other rehabilitation programmes have focused on modifying risk factors such as smoking and diet. For example, van Elderen, Maes and van den Broek (1994) developed a health education and counselling programme for patients with cardiovascular disease after discharge from hospital, with weekly follow-ups by telephone. Although this study involved only a small number of patients, the results seemed to provide some support for including health education in CHD rehabilitation programmes.
The risk factors for CHD can be understood and predicted by examining an individual’s health beliefs. Psychology’s role is to both understand and attempt to change these behavioural risk factors.
Smoking is estimated to be the cause of one in four deaths from CHD. Smoking more than 20 cigarettes a day increases the risk of CHD in middle-age threefold. Giving up smoking can halve the risk of another heart attack in those who have already had one.
Diet and exercise (especially cholesterol levels) have also been implicated in CHD. It has been suggested that the 20 per cent of a population with the highest cholesterol levels are three times more likely to die of heart disease than the 20 per cent with the lowest levels. We can reduce cholesterol by cutting down total fats and saturated fats in our diet, and increasing polyunsaturated fats and dietary fibre. Other risk factors include excess coffee and alcohol and lack of exercise.
High blood pressure is another risk factor – the higher the blood pressure, the greater the risk. Even a small decrease in the average blood pressure of a population could reduce the mortality from CHD by 30 per cent. Blood pressure appears to be related to a multitude of factors, such as genetics, obesity, alcohol intake and salt consumption.
Type A behaviour is probably the most extensively studied risk factor for CHD. Friedman and Rosenman (1959) initially defined type A behaviour as excessive competitiveness, impatience, hostility and vigorous speech. In 1978, using a semi-structured interview, they identified two types of type A behaviour. Type A1 is characterized by vigour, energy, alertness, confidence, loud speaking, rapid speaking, tense clipped speech, impatience, hostility, interrupting,frequent use of the word ‘never’ and frequent use of the word ‘absolutely’. Type A2 was defined as being similar to type A1, but not as extreme, and Type B behaviour was regarded as relaxed (for example, showing no interruptions of others’ speech) and quieter.
Stress has also been extensively studied as a predictor of CHD. In the 1980s Karasek developed a job demand/job control model of stress. He proposed the ‘job demand control hypothesis’, which includes the concept of job strain (see chapter 20). According to Karasek and colleagues (e.g. Karasek & Theorell, 1990), there are two aspects of job strain: i) job demands (which reflect conditions that affect performance) and ii) job autonomy (which reflects theperson’s control over the speed or the nature of decisions made within the job). Karasek’s hypothesis suggests that high job demands and low job autonomy predict CHD. More recently, Karasek developed the hypothesis further to include the concept of social support. This is deemed to be beneficial for CHD, and is defined in terms of emotional support (i.e. trust between co-workers and social cohesion) and instrumental social support (i.e. the provision of extra resources and assistance).
Rehabilitation programmes
Modifying exercise – Most rehabilitation programmes emphasize exercise as the best route to physical recovery, on the assumption that this will in turn promote psychological and social recovery, too. But whether, more generally, these programmes influence risk factors other than exercise (such as smoking, diet and Type A behaviour) is questionable. Modifying type A behaviour – The recurrent coronary prevention project was developed by Friedman et al. (1986) in an attempt to modify type A behaviour. It is based on the following questions: ‘Can type A behaviour be modified?’ and ‘Could such modification reduce the chances of a recurrence?’ The study involved a five-year intervention and1000 participants who had all suffered a heart attack. They were allocated to one of three groups: (i) cardiology counselling, (ii) type A behaviour modification, or (iii) no treatment. Type A behaviour modification involved: discussions of beliefs, values and ways to reduce work demands and increase relaxation, and education about changing the individual’s cognitive framework. At five years, the type A modification group showed a reduced recurrence of heart attacks, suggesting that such intervention programmes may reduce the probability of reinfarction in ‘at risk’ individuals.Modifying general lifestyle factors Other rehabilitation programmes have focused on modifying risk factors such as smoking and diet. For example, van Elderen, Maes and van den Broek (1994) developed a health education and counselling programme for patients with cardiovascular disease after discharge from hospital, with weekly follow-ups by telephone. Although this study involved only a small number of patients, the results seemed to provide some support for including health education in CHD rehabilitation programmes.
No comments:
Post a Comment