Use of Family History in Clinical Guidelines for Diabetes and Colorectal Cancer

Background Family history is a risk factor for many chronic diseases and as such is often incorporated into clinical practice guidelines. Purpose To assess the consistency of the use of family history in selected guidelines for colorectal cancer (CRC) and type 2 diabetes mellitus (T2DM) and to examine how these definitions influence their screening recommendations. Methods Using a web-based search, guidelines issued between 2001 and 2011 from Australia, Canada, the United Kingdom, the U.S., and the WHO were reviewed. In total, 21 guidelines were found that included family history information (14 for CRC and seven for T2DM). For each guideline, the definition of family history and the way this definition influenced screening recommendations was recorded. Analyses were completed on May 2011. Results Family history was defined most often as the presence of affected first-degree relatives; the number of such relatives and their ages at diagnosis were considered sometimes in making specific recommendations. The definition of family history and its impact on recommendations varied substantially, even for the same disease. Conclusions Despite the importance of family history as a risk factor for CRC and T2DM, its use in screening recommendations is inconsistent among guidelines from major organizations; however, differences do not appear large enough to prevent achieving consensus among the guidelines for each disease. More standardized recommendations for use of family history in CRC and T2DM screening guidelines could enhance their utility for prevention.