title: Substance dependence: Decades apart in a teaching hospital.
abstract: OBJECTIVE
  The present study was done to understand the changing trends in substance dependence across decades.
  
  
  METHODS
  It is a retrospective study done in Department of Psychiatry in a Teaching Hospital setting. The data of patients who attended the OPD for substance dependence during the months January to December in the years 1985 & 1986, 1995 & 1996 and 2005 & 2006 were collected and analysed.
  
  
  METHODS
  A total of 839 new patients with substance dependence identified according to International Classification of Diseases (ICD) (n = 839) was analysed in the present report. Study variables taken into account are alcohol dependence, polysubstance dependence which also includes alcohol, age, sex, age of initiation of substance use, duration of use, and comorbidity.
  
  
  METHODS
  Z-test, Chi-square test, mean, percentages, standard deviation.
  
  
  RESULTS
  Substance dependence constituted 5.32% in 1985 and 1986, 5.02% in 1995 and 1996, and 4.05% in 2005 and 2006 of the newly registered total psychiatric patients. The variation in incidence figures across the years is statistically not significant (P > 0.05). Among the substance dependents 2% in 1985 & 1986, 1% in 1995 & 1996 and 1% in 2005 & 2006 were females. Majority of the patients were alcohol dependent (87.2% in 1985 and 1986, 89.4% in 1995 and 1996, and 79.6% in 2005 and 2006). Polysubstance dependence showed an increasing trend and it was statistically significant. Comparison of the years 1985 and 1986 with 2005 and 2006 gives Z = 2.4, P < 0.05 (statistically significant). Comparison of the years 1995 and 1996 with 2005 and 2006 gives Z = 3, P < 0.01 (significant statistically). Number of people getting initiated to substance use in early age (viz. 10-19 years) showed an increasing trend. People with positive family history of substance dependence started using substances early in life. (Chi-square value: 164.7, P < 0.0001, significant statistically). In polysubstance dependence comorbidity was more (Z = 4.1, P < 0.001, significant statistically).
  
  
  CONCLUSIONS
  Incidence of substance dependence remained the same across the two decades. But incidence of polysubstance dependence is increasing over the years. People start using substances earlier and are becoming dependent earlier in their lives in the present decade. Polysubstance dependence is correlated with greater comorbidity. Early recognition of comorbidity and its management is essential for better prognosis. Substance dependence is exclusively a male diagnosis in our population.
authors.affiliation: Department of Psychiatry, Thanjavur Medical College, Thanjavur, Tamilnadu, India.
authors.forename: J
authors.initials: J
authors.lastname: Venkatesan
authors.forename: Stelina S D
authors.initials: SS
authors.lastname: Suresh