2-hour Insulin

Insulin was measured on EDTA plasma, which was collected via blood draw two hours after an oral glucose challenge. Specimens were stored at -80 until testing. Assays were performed in the Mass General Hospital, Diabetes Laboratory, using an RIA method (Linco Research, Inc).

In 1948, researchers recruited men and women from the town of Framingham, Massachusetts, beginning the first round of extensive physical examinations and lifestyle interviews that would later be analyzed for common patterns related to CVD development.

Initially, the Framingham Heart Study enrolled 5209 men and women from the Framingham area who were between the ages of 28 and 62 years. Beginning in 1971, the Framingham Heart Study enrolled 5,124 men and women, who were either offspring of the original cohort or spouses of those offspring. In 2002, 4095 third generation participants (men and women) were enrolled.

During each clinic exam cycle, the participants undergo a detailed examination including physical examination, medical history, laboratory testing, and electrocardiogram. Over the years, other tests (that may not be performed at every exam cycle) have included pulmonary function, lifestyle, physical function, cognitive function questionnaires, and various noninvasive cardiovascular tests including echocardiograms. The content of each exam cycle differs for Original, Offspring and Generation 3 cohorts and can be found in the Exam Cycle Protocol Manuals.

• Study Weblinks:
  • The Framingham Heart Study
• Study Design:
  • Prospective Longitudinal Cohort
• Study Type:
  • Longitudinal
• Total number of consented subjects: 1107
• Subject Sample Telemetry Report (SSTR)

An oral 75 gram glucose tolerance test was administered to select participants at the seventh examination cycle using the following criteria from the fifth examination cycle:

1. all participants with impaired fasting glucose (FBS = 110-125 mg/100ml) or impaired glucose tolerance (2 hour post-challenge BS = 140-199 mg/100ml)
2. a subset of subjects with normal fasting glucose (FBS < 110 mg/100ml) were block-randomly selected from quintiles of fasting blood sugar

The Original cohort began Exam 1 in 1948 (9/1948 - 4/1953) and has continued with biennial examinations to the present.

The Offspring cohort began Exam 1 in 1971 (8/1971 - 9/1975) and has on average been examined every 3 to 4 years since enrollment. However, there was an eight year window between exam 1 and exam 2. Exam 7 was performed from 9/1998 - 10/2001.

The Generation 3 cohort Exam 1 was performed 4/2002 - 7/2005.

Examinations continue to be performed.

• Primary Phenotype: Cardiovascular System

• Investigators
  • Peter Wilson, MD. Emory University, Atlanta, GA, USA.
  • James Meigs, MD. Massachusetts General Hospital, Boston, MA, USA.
• Institutions
  • The National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
  • Boston University, Boston, MA, USA.