Predicting and changing behavioural risk factors for CHD
CHD is strongly linked with a range of behavioural risk factors. Some research has
addressed whether these risk factors can be changed.1 Smoking. One in four deaths from CHD is thought to be caused by smoking. Smoking
more than 20 cigarettes a day increases the risk of CHD in middle age threefold. In
addition, stopping smoking can halve the risk of another heart attack in those who
have already had one. Smoking cessation is discussed in Chapter 5.
2 Diet. Diet, in particular cholesterol levels, has 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. Cholesterol levels may be determined by the amount of saturated fat consumed
(derived mainly from animal fats). Cholesterol reduction can be achieved through a
reduction in total fats and saturated fats, an increase in polyunsaturated fats and an
increase in dietary fibre. Dietary change is discussed in Chapter 6 and under the
dietary section.
3 High blood pressure. High blood pressure is also a risk factor for CHD – the higher
the blood pressure the greater the risk. It has been suggested that a 10 mmHg
decrease in a population’s average blood pressure could reduce the mortality attri-
butable to heart disease by 30 per cent. Blood pressure appears to be related to a
multitude of factors such as genetics, obesity, alcohol intake and salt consumption.
Other possible behavioural risk factors include exercise, coffee, alcohol and soft
water consumption. The risk factors for CHD can be understood and possibly changed
by examining and modifying an individual’s health beliefs (see Chapters 2, 6, 7 and 9).
4 Type A behaviour and hostility. Type A behaviour and its associated characteristic,
hostility is probably the most extensively studied risk factor for coronary heart disease
(see Chapter 11 for details). Support for a relationship between type A behaviour and
CHD has been reported by a number studies (Rosenman et al. 1975; Jenkins et al.
1979; Haynes et al. 1980). However, research has also reported no relationship
between type A behaviour and CHD (e.g. Johnston et al. 1987). Recent research has
focused on more on hostility which has been shown to predict stress reactivity and to
be linked to the development of CHD (e.g. Williams and Barefoot 1988; Houston
1994; Miller et al. 1996).
5 Stress. Stress has also been studied extensively as a predictor of CHD and research
has shown links between stress reactivity and CHD, life events and CHD and job stress
and CHD (see Chapters 10 and 11). Stress management is used to reduce stress in
people already diagnosed with CHD (see below). However, interventions have also
been developed to reduce stress in non patient samples. For example, Jones and John-
ston (2000) developed and evaluated a stress management intervention to reduce
distress in 79 student nurses who had previously reported significant distress. Sub-
sequent changes were compared to a waiting list control group. The results showed
that the intervention produce significant reductions in anxiety, depression and
domestic satisfaction. In addition, the nurses showed an increase in direct coping. In
line with this latter finding, some interventions have directly challenged how people376 HEALTH PSYCHOLOGY