Evaluating the psychological effects of genetic testing in symptomatic patients: a systematic review.

Most research on the effects of genetic testing is performed in individuals at increased risk for a specific disease (presymptomatic subjects) but not in patients already affected by disease. If results of these studies in presymptomatic subjects can be applied to patients is unclear. We performed a systematic review to evaluate the effects of genetic testing in patients and describe the methodological instruments used. About 2611 articles were retrieved and 16 studies included. Studies reported great variety in designs, methods, and patient outcomes. In total, 2868 participants enrolled of which 62% were patients. Patients appeared to have a lower perceived general health and higher levels of anxiety and depression than presymptomatic subjects before genetic testing. In the long term no psychological impairment was shown. We conclude that patients differ from presymptomatic subjects and may be more vulnerable to negative effects of genetic testing. Conclusions from earlier research on presymptomatic genetic testing cannot be generalized to patients, and more standardized research is needed.