Delivery of genomic medicine for common chronic adult diseases: a systematic review

Abstract

Context: The greatest public health benefit of advances in understanding the human genome may be realized for common chronic diseases such as cardiovascular disease, diabetes mellitus, and cancer. Attempts to integrate such knowledge into clinical practice are still in the early stages, and as a result, many questions surround the current state of this translation.

Objective: To synthesize current information on genetic health services for common adult-onset conditions by examining studies that have addressed the outcomes, consumer information needs, delivery, and challenges in integrating these services.

Data sources: MEDLINE articles published between January 2000 and February 2008.

Study selection: Original research articles and systematic reviews dealing with common chronic adult-onset conditions were reviewed. A total of 3371 citations were reviewed, 170 articles retrieved, and 68 articles included in the analysis.

Data extraction: Data were independently extracted by one reviewer and checked by another with disagreement resolved by consensus. Variables assessed included study design and 4 key areas: outcomes of genomic medicine, consumer information needs, delivery of genomic medicine, and challenges and barriers to integration of genomic medicine.

Data synthesis: Sixty-eight articles contributed data to the synthesis: 5 systematic reviews, 8 experimental studies, 35 surveys, 7 pre/post studies, 3 observational studies, and 10 qualitative reports. Three systematic reviews, 4 experimental studies, and 9 additional studies reported on outcomes of genetic services. Generally there were modest positive effects on psychological outcomes such as worry and anxiety, behavioral outcomes have shown mixed results, and clinical outcomes were less well studied. One systematic review, 1 randomized controlled trial, and 14 other studies assessed consumer information needs and found in general that genetics knowledge was reported to be low but that attitudes were generally positive. Three randomized controlled trials and 13 other studies assessed how genomic medicine is delivered and newer models of delivery. One systematic review and 19 other studies assessed barriers; the most consistent finding was the self-assessed inadequacy of the primary care workforce to deliver genetic services. Additional identified barriers included lack of oversight of genetic testing and concerns about privacy and discrimination.

Conclusion: Many gaps in knowledge about organization, clinician, and patient needs must be filled to translate basic and clinical science advances in genomics of common chronic diseases into practice.