Early onset of substances use disorders (SUD) has been related to some personality characteristics and a higher prevalence of social, psychiatric and organic problems.

To describe personality differences in early onset of alcohol use (EO, age≤ 15) subjects and late onset of alcohol use (LO, age≥16), both affected of acute non-substance use psychiatric disorders (Non-SUD) and alcohol related substance use disorders (alcohol SUD).

Data on sociodemographic and clinical factors were gathered among subjects meeting DSM-IV criteria of alcohol SUD. Psychometric characteristics were explored with TCI-R.

The whole sample (N = 188; age 36,8 ± 9,2; 71,4% male) showed mainly hallucinations/delusions (37,7%) at admittance and personality disorders (50,3%) as a most prevalent non-SUD. Most common comorbid SUD were alcohol (59,5%).

EO subjects (N = 103) had more prevalence of legal problems (51,4% vs. 15,9%), sedatives misuse (73,8% vs. 54,1%), polydrug abuse (2 ± 1,1 vs. 1,6 ± 1,0) and higher score in ASI psychopathology (5,8 ± 1,3 vs. 4,8 ± 1,8). Most frequent dual diagnosis in EO subjects were psychosis+cannabis SUD (8,7%).

EO group was characterized by higher impulsiveness (102,9 ± 16,4 vs 97,0 ± 14,5), disorderliness (127,6 ± 19,2 vs. 117,4 ± 21,7), harm avoidance (30,7 ± 4,9 vs. 28 ± 7,6), eagerness of effort (34,7 ± 7,5 vs. 31,6 ± 8,0), ambitious (19,2 ± 4,6 vs. 17,9 ± 3,1), perfectionist (29,8 ± 5,9 vs. 27,8 ± 6,2), responsibility (30,5 ± 6,9 vs. 27,9 ± 7,7), resourcefulness (25,9 ± 6,3 vs. 23,2 ± 6,8), enlightened second nature (17,7 ± 3,9 vs. 13,9 ± 4,6), social acceptance (32,0 ± 5,8 vs. 29,4 ± 7,1) and lower anticipatory worry (71,7 ± 18,5 vs. 79,8 ± 17,9), dependence (54,5 ± 12,4 vs. 59,2 ± 14,9).

EO was characterized by higher scores in impulsiveness, disorderliness, and self-directedness and showed more severity on social, psychopathologic and substance problems.