Background: Several lines of evidence suggest that the multisystem disease seen in drug addicts may reflect acceleration of underlying degenerative or ageing processes. Patients presenting for management of their clinical opiate substance use disorder (SUD) were therefore compared with general medical non-SUD (N-SUD) patients.
Methods: Differences in dental, psychiatric and hair graying indices at both temple and vertex were studied and combined with principal component (PC) analysis. Arcsinh transformation of the data were considered, as this improved the normality of the parameter distributions.
Results: 95 opiate dependent SUD and 32 N-SUD patients were studied. The mean (±SD) ages were 33.47±7.98 vs 57.81±17.13 years and sex was 75.8% and 63.6% male (p - n.s.) in the SUD and N-SUD groups respectively. The addicted population was more severe as a function of age on all indices (p<0.05). The arcsinh transformation of PC1+PC2 was significantly different by addiction status both as a category on its own and after interaction with age (both p<0.0005), and was associated with a calculated 22.3% age advancement at 60 years of age. Interactions between age, and PC's of opiate and inhaled intoxicant dose and duration of exposure were highly significant (p<0.01). Tobacco, cannabis, heroin and methadone dose and/or duration of exposure were significantly related to the identified physiological deficit both alone, and as interactions with each other and with age (most interactions p<0.01).
Conclusions: These findings have implications for understanding the pathophysiology of drug addiction and imply that the high rate of morbidity seen in drug dependent patients may be related to underlying subclinical ager related changes, choice of opiate pharmacotherapeutic agent, considerations of duration of treatment, and conversely for the pathophysiology of the development of age related disease.