Family History for Public Health and Preventive Medicine: Developing a Research Agenda Paula Yoon, ScD, MPH Office of Genomics & Disease Prevention CDC

Could disease information about a person’s close relatives be used to predict their own risk for specific diseases? Why this workshop -- Would individuals who may be at above average risk benefit from targeted interventions beyond what is recommended for the population at large ?

Purpose of the workshop -- Discuss the potential of family history for disease prevention and determine what information is needed in order to assess the validity and utility of this approach.

Workshop goals --  Identify diseases and selection criteria  Describe specifications for a FH tool  Identify knowledge gaps in AV, CV, CU  Describe ethical, legal and social implications  Describe studies needed to fill knowledge gap  Identify potential sources of existing data  Describe new studies that may be needed

What is family history?  reflects the consequences of genetic susceptibilities, shared environment, and common behaviors  ranges from knowing whether a parent or sibling had a specific disease to a very detailed pedigree analysis

Family history for public health and preventive medicine  simple, easily applied, inexpensive  can identify people at high and moderate risk  can be used in combination with other risk factors  useful for targeting interventions  positively influences healthy behaviors

Family history for public health and preventive medicine  population-based uses of FH  e.g., Behavioral Risk Factor Surveillance System  stratify risk factors by FH  target interventions  evaluate trends over time

Prevalence and relative risk estimates due to family history for chronic diseases CVD58 mill2.0 – 5.4 Breast cancer3 mill wom2.1 – 3.9 Colorectalincid = 130, – 4.9 Prostateincid = 200, – 11.0 Melanoma200, – 4.3 Type II diabetes13 mill2.4 – 4.0 Osteoporosis8 mill wom2.0 – mill men Asthma17 mill3.0 – 7.0

Risk estimates for colorectal cancer for 3 family history risk groups Average Moderate High (no FH) (one 1° relat) (>one 1° relat) FH preval9/101/101/ /8,000 Absolute ~1 Relativeref ~30 Attributable

Evaluation framework

Analytic validity -- How accurately and reliably does the FH tool identify disease among a person’s relatives? FH tool “gold standard” A B - C D analytic sensitivity = A / (A+C) analytic specificity = D / (B+D)

Clinical validity -- How accurate and reliable is FH for stratifying disease risk and predicting future disease? FH Future disease A B - C D clin sensitivity = A / (A+C) clin specificity = D / (B+D) PPV = A / (A+B) NPV = D / (C+D)

Clinical utility -- What are the benefits and risks accruing from both negative and positive family history?  will targeted interventions based on FH prevent disease?  is FH useful for changing behavior?  is the approach cost-effective?  are there risks associated with collecting and using FH?

Ethical, legal and social implications --  stigma associated with above average risk  psychological impact of risk label  discrimination or adverse effects on personal and family life  informed consent requirements  safeguards to protect privacy and confidentiality

Evaluation framework

Potential of family history Jim Fixx