Differences in the associations between psychoactive substance use and alexithymia: A series of meta-analyses  

The present meta-analytic study examined the association between alexithymia and psychoactive substance use. Studies published from 1988 to August 20, 2022 were identified by a systematic search and 168 eligible studies were included in five meta-analyses. Results showed that (1) the correlation between substance use and alexithymia is small but significant (r = 0.177); (2) substance users have substantially higher alexithymia than nonusers (g = 0.545); (3) alexithymic participants have significantly but slightly higher levels of substance use than non-alexithymics (g = 0.242); (4) substance users are significantly but only slightly more likely to be alexithymic than nonusers (OR = 2.392); and (5) alexithymic individuals are not more likely to be substance users than non-alexithymics. Larger effects were observed among samples diagnosed with substance use disorder (SUD), and the use of depressants, alcohol, opiates, and illicit stimulants had stronger relation to alexithymia. We found a tendency for a larger association with problematic use as compared to other indicators (e.g., frequency and duration) of substance use. Among the components of alexithymia, difficulties in identifying feelings has the strongest association with substance use. Our findings support clinical practice by suggesting the improvement of emotion regulation in SUD.