Background
The Framingham Heart Study (FHS) began in 1948 and was conducted by the National Heart, Lung and Blood Institute. This study was influenced by the uptake in mortality rates caused by cardiovascular disease (CVD). The purpose of the FHS was to identify risk factors for cardiovascular disease in a cohort design. CVD risk factors have since become an integral piece to modern medicine including treatment and preventative strategies (Cupples et al., 2003, p.1). In this Data Analysis Project, we will analyze a random sample of a 500 individual data set pulled from the FHS. We will test the claim that most individuals that participated in the study were smokers at baseline at the time of examination and to conclude whether or not those who are overweight have increased risk for developing CVD.
Key study question(s)
Is there a correlation between weight and use of cigarettes?
Are those who are overweight more likely to develop cardiovascular disease?
Methods
5,209 participants were recruited for the Framingham Heart Study, 2336 men and 2873 women, between the ages of 30-60 based in Framingham, Massachusetts. This specific town was selected at the time as it was believed to have a relatively stable population that was thought to reflect many communities. The participants had not experienced any symptoms of CVD or cardiovascular health concern. Eligible participants completed a baseline evaluation and interview and undergo a screening every two years. When ten years have passed the participant will have a medical evaluation to determine if any development of CVD has taken place (Cupples, et al., 2003).
A one-way frequency table was developed using a 95% confidence interval and the variable “current smoker.” An asymptomatic binomial test was also included in this chart in order to test the hypothesis that over 50% of participants reported smoking during their entrance interview. The p-value was calculated as 1-0.3942 and compared to the alpha value of 0.05 it can be determined that there is enough evidence to support the alternative hypothesis of those who were smokers is greater than 0.50. This is based on the null hypothesis of p=0.50 and the alternative, p > 0.50.
The variable BMI was used in testing the hypothesis that a risk factor for coronary heart disease is being overweight. This was determined by conducting a one sample t-test using the alternative hypothesis of BMI>25 and a significance level of 0.05.
Findings
After a random sample of 500 participants were selected from the study, it was determined whether or not most participants were smokers at the time of the entrance interview. Next, it was determined whether or not being overweight is a risk of developing cardiovascular disease by using the Center for Disease Controls and Preventions guideline of BMI > 25.
Public health significance
“Overweight, obesity and smoking are well-established risk independent factors for cardiovascular diseases. The combination of overweight or obesity with smoking may modify other cardiovascular disease risk factors.”
Akbartabartoori M, Lean ME, Hankey CR. Smoking combined with overweight or obesity markedly elevates cardiovascular risk factors. Eur J Cardiovasc Prev Rehabil. 2006 Dec;13(6):938-46. doi: 10.1097/01.hjr.0000214613.29608.f5. PMID: 17143126.