Framingham Heart Study

As the longest standing heart health study in the world, Framingham Heart Study, at Framingham, Massachusetts, continues to mine vast data for the last sixty years regarding the cause of heart trouble and care. The Framingham heart study has played a major role in identifying key risk factors for cardiovascular disease.

The first round of extensive physical examinations and lifestyle studies was conducted on 5,209 men and women who were healthy and ranging in ages 30 to 62 in the 1948. Since then, every two years, detailed medical history, physical examinations and diagnostic tests are carried out on the identified men and women folks. Participants in the study has been tracked using standardized biennial cardiovascular examination, daily surveillance of hospital admissions, information pertaining to death and information obtained from the physicians and sources outside the clinic.

In 1971, a second generation of 5,124 original participants' adult children and spouses were enrolled for similar examinations. Again in year 2002, enrollment of third generation participants, the grandchildren of the original cohort had begun. This is considered as a vital step to increase the understanding of heart disease and stroke and how these affect families. This third generation study was completed in July 2005 and it involved 4,095 participants.

Recently, the study has integrated new diagnostic technologies such as echocardiography, carotid artery ultrasound, magnetic resonance imaging of heart and brain, CT scans of the heart and bone densitometry into the past and ongoing protocols. Framingham heart study, after decades of careful monitoring of the population has led to identification of major Cardiovascular Disease risk factors namely:

• High blood pressure
  
• Cholesterol
  
• Smoking
  
• Obesity
  
• Diabetes
  
• Physical inactivity
  
• Factors such as blood triglycerides, HDL cholesterol levels, age and gender.

The Framingham heart study risk score was primarily designed to predict a 10-year risk for Coronary Heart Disease but subsequent analysis has revealed that the risk score is very effective in predicting the short term cumulative risk for CHD. This is also applicable in the context of competing risk of death from non coronary causes.

However, there are criticisms that the study's risk model does not perform well in predicting life time risk score in younger subjects. This is attributed to changes in risk factor status that occur over time. Rates of hypertension and diabetes seem to increase sharply with age and this may alter the long time risk of younger patients in an unpredictable manner.