of the comorbid disorder is a plausible confounding factor, since individuals with an early onset of mental disorders exhibit early alcohol consumption and usually have an early age at interview. Therefore, the fact that social phobia is the sole mental disorder associated with an early alcohol dependence could be related to the observation that specific phobia is the mental disorder with the earliest age at onset. Furthermore, the temporal sequencing of specific phobia and alcohol dependence is unusual among anxiety and mood disorders, since specific phobia, like social phobia, often precedes alcohol dependence whereas alcohol dependence is temporally primary to all other disorders, including panic disorder, general anxiety disorder, dysthymia, major depression, and mania/hypomania. Other axis I disorders, including mood and anxiety disorders were not associated with an early age at onset of alcohol dependence. This finding is consistent with the fact that most historical and contemporary classifications of alcohol dependence do not include psychiatric disorders.
