A study was conducted for an association between endogenous

A study was conducted for an association between endogenous catecholamine level (CAT) and subsequent seven-year incidence of coronary heart disease (CHD) among a group of 609 white males. The endogenous catecholamine level was classified into high and low categories. The data are given below: Identify the risk factor for the above study. What is the relative risk of developing CHD for the high CAT group to the low CAT group Interpret the result you obtained in part b). Is the risk factor protective Why or why not

Solution

a) Risk factors are variables that increase the likelihood of the outcome in question

Here variable High CAT is the risk factor since there is a higher probability of CHD being developed

b) Probability of developing CHD for the HIGH CAT group = No of people who have developed CHD/No of people who have High CAT = 27/122

Probability of developing CHD for the Low CAT group = No of people who have developed CHD/No of people who have Low CAT = 44/487

Relative risk of developing CHD for the High CAT group to the low CAT group = Probability of developing CHD for the HIGH CAT group / Probability of developing CHD for the Low CAT group

                             = (27/122) / (44/487)

                             = 2.45

c) A subject with High CAT has 57% the chance of developing CHD as a subject with Low CAT

d) The risk factor High CAT is not protective as it does not reduce the probability of CHD being developed