There have been no trials in healthcare settings of genetic susceptibility feedback in relation to alcohol consumption. The purpose of this study was to determine the feasibility and acceptability of conducting a full-scale randomised trial estimating the effect of personalised genetic susceptibility feedback on alcohol consumption in hospital outpatients with risky drinking.
In the study, outpatients ≥18 years of age who reported drinking more than 14 standard drinks in the past week or in a typical week were asked to provide a saliva sample for genetic testing. Genetic susceptibility feedback was posted to participants 6 months after recruitment. The co-primary outcomes were the proportion of participants who (i) provided a saliva sample that could be genotyped, and (ii) spoke with a genetic counsellor. Secondary outcomes included changes in patients’ weekly alcohol consumption; scores on scales measuring readiness to change, importance of changing and confidence in ability to change drinking habits; knowledge about which cancers are alcohol-attributable; and acceptability of the saliva collection procedure and the genetic-feedback intervention. McNemar’s test and paired t-tests were used to test for differences between baseline and follow-up in proportions and means, respectively.
Of 100 participants who provided a saliva sample, 93 had adequate DNA for at least one genotyping assay. Three participants spoke to a genetic counsellor. Patients’ readiness to change their drinking, their views on the importance of changing and their stated confidence in their ability to change increased between baseline and follow-up. There was no increase in patients’ knowledge about alcohol-attributable cancers nor any reduction in how much alcohol they drank 4 months after receiving the feedback. Most participants (80%) were somewhat comfortable or very comfortable with the process used to collect saliva, 84% understood the genetic feedback, 54% found it useful, 10% had sought support to reduce their drinking after receiving the feedback, and 37% reported that the feedback would affect how much they drink in the future.
The researchers concluded that the results of this study suggested it would be feasible to conduct a methodologically robust trial estimating the effect of genetic susceptibility feedback on alcohol consumption in hospital outpatients with risky drinking.