RÉSUMÉ
Background & objectives: The patterns of abused psychoactive substances change over time, and it is important to document such changes. The present retrospective study was carried out to document these changes in patients registered in a de-addiction centre in north India over three decades. Methods: Case notes of all patients registered in the centre from September 1978 till December 31, 2008 were reviewed. Comparisons were made among three decades (1978-1988, 1989-1998, and 1999-2008). Results: The number of registered subjects increased eight-fold over the decades, and age of the subjects presenting for the treatment decreased. The percentages of subjects presenting for the treatment with opioid dependence were 36.8 per cent (n=204), 42.9 per cent (n=809) and 53.2 per cent (n=2219), respectively for the three decades (P<0.001). The proportion of subjects using natural opioids decreased over the three decades (47.4, 26.5 and 18.3%; P<0.001), with a concomitant emergence and/or increase of newer and prescription opioids such as buprenorphine, codeine and dextropropoxyphene. Dependence on tobacco and sedative-hypnotics also increased, and inhalant abuse was reported especially in the third decade. Polysubstance dependence increased significantly over the decades (P<0.001). Interpretation & conclusions: Our results showed major shifts in the patterns of substance abuse in clinic-attending patients in north India over the three decades from 1978 till 2008. These have important implications for all the stakeholders concerned with combating the challenge of psychoactive substance abuse in our society.