Direct-to-consumer genetic testing is becoming more and more apparent even though its clinical validity and utility are pretty questionable regarding medical decisions. Eric Topol and his team now studied over 2000 patients who had genomic tests (Navigenics) and reported if there was any changes in symptoms of anxiety, intake of dietary fat, and exercise behavior. The results are not surprising therefore they raise the question whether these tests can be used for anything at all. The study was published in NEJM.
From a cohort of 3639 enrolled subjects, 2037 completed follow-up. Primary analyses showed no significant differences between baseline and follow-up in anxiety symptoms (P=0.80), dietary fat intake (P=0.89), or exercise behavior (P=0.61). Secondary analyses revealed that test-related distress was positively correlated with the average estimated lifetime risk among all the assessed conditions (β=0.117, P<0.001). However, 90.3% of subjects who completed follow-up had scores indicating no test-related distress. There was no significant increase in the rate of use of screening tests associated with genomewide profiling, most of which are not considered appropriate for screening asymptomatic persons in any case.
In a selected sample of subjects who completed follow-up after undergoing consumer genomewide testing, such testing did not result in any measurable short-term changes in psychological health, diet or exercise behavior, or use of screening tests. Potential effects of this type of genetic testing on the population at large are not known.
(Hat tip: Medgadget)