Iranian Journal of

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Background and Objectives: Hepatitis B virus (HBV) infection is a major public health problem worldwide. Islamic Republic of Iran is located in mesoendemic region (prevalence 2%-7%). The aim of this study was to assess prevalence of chronic HBV in Iran according to demographic characteristics.
Methods: Medline, Embase, Science Citation Index Expanded, Ovid, Google Scholar, IranMedex, SID, Magiran and The Scientific Journal of Iran Blood Transfusion Organization (SJIBT) from 2000 till May 2008 were searched. Cross-sectional studies concerning prevalence of hepatitis B infection in Iran were included irrespective of language and date. The outcome of interest was prevalence of chronic HBV infection detected by blood specimen positive for HBsAg.
Results: We icluded 34 studies. The prevalence of chronic HBV infection was estimated about 1.7% or lower in general population 0.8% (95% CI: 0.6%-0.9%) in blood donors and 3.2% (95% CI: 2.3% - 4.1%) in intravenous drug users. Prevalence of chronic HBV infection in beta thalassemic patients varied from zero to 1.5%. Prevalence of chronic HBV infection was higher in middle aged and elders than children, adolescent and youth and was 25% higher in males than females.
Conclusions: Since mass vaccination of hepatitis B in 1993, prevalence of chronic HBV infection has being reduced among children and adolescents. These age groups comprise a large proportion of general population and reduction of HBV infection in this age group may impact on total prevalence of hepatitis B infection, so that now Iran may be considered a hypoendemic region for HBV infection.

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Background & Objectives: The aim of the study was to determine age, period, and cohort effects on trend of alcohol and drug use in the students of Tehran University of Medical Sciences from 2006 to 2009.

Methods: Between 2006 and 2009, the students of Tehran University of Medical Sciences were surveyed annually using a structured self-administered and anonymous questionnaire. Intrinsic estimator, which is a new method for resolving linear dependency between age, period, and cohort in linear regression models, was used for data analysis.

Results: In the present study, in the descriptive method, the prevalence of alcohol consumption increased in males and females with an increase in age. The prevalence of illicit drug use was higher in 2007 in comparison with other periods for males and females. In the analytical method (intrinsic estimator), there were no age, period and cohort effects for alcohol and drug use for females. For males, the age effect exhibited an increasing-decreasing-increasing trend and period and cohort effects showed a decreasing trend for alcohol use. As for drug use, the age effect exhibited gradual increases. The period effect displayed an increasing-decreasing trend and the cohort effect exhibited an increasing-decreasing-increasing trend.

Conclusion: The IE method showed no age, period and cohort effects for alcohol and drug use in females. The prevalence of drug and alcohol use increased with an increase in age in males. The high prevalence of drug use could be due to easy accessibility and low price of drugs.