Opioid medication use and blood DNA methylation: epigenome-wide association meta-analysis.

To identify differential methylation related to prescribed opioid use. This study examined whether blood DNA methylation, measured using Illumina arrays, differs by recent opioid medication use in four population-based cohorts. We meta-analyzed results (282 users; 10,560 nonusers) using inverse-variance weighting. Differential methylation (false discovery rate <0.05) was observed at six CpGs annotated to the following genes: , , , , and . Integrative epigenomic analyses linked implicated loci to regulatory elements in blood and/or brain. Additionally, 74 CpGs were differentially methylated in males or females. Methylation at significant CpGs correlated with gene expression in blood and/or brain. This study identified DNA methylation related to opioid medication use in general populations. The results could inform the development of blood methylation biomarkers of opioid use.