مجله اپیدمیولوژی ایران
سال پنجم شماره 3 (پیاپی 15، پاییز 1388)

Numerous studies have reported beneficial effects of smoking cessation in terms of decreased cardiovascular mortality in patients with coronary heart disease. This paper aimed to determine a valid estimate for the relative risk of mortality in subjects who quit smoking compared to those continued smoking. All relevant prospective cohort studies of chronic heart disease published during 1975 to 2008 were considered. Studies with at least two years follow-up were eligible for analysis. The qualities of studies were assessed independently by two reviewers. In addition, to obtain a precise estimate, we used the sample size and the follow-up duration of each study as the covariates in the Bayesian meta-analysis model. The Winbugs and Boa softwares were utilized for fitting the Bayesian meta-analysis model. The estimate of relative risk of mortality for those who quit smoking compared to those continued smoking was 0.64 (95%CI: 0.57-0.70). We also did not find any significant relationship between the estimate of risk reduction and the described covariates. Using this Bayesian meta-analysis, a 36% reduction in relative risk of mortality was found for those who quit smoking compared to those continued smoking, after eliminating the effects of study sample size and follow-up duration.

Road traffic injuries (RTIs) are the leading cause of burden of disease in Iran. Determination of road safety situation as a complex issue can reduce injury and death rates on roads. This study aimed to determine the effective indicators of road safety and introduce approaches to combine different indicators for implementation index to assess the road safety situation of Iran. In this analytical and comparative study eleven indicators which have been categorized in nine dimensions were employed. Indicators normalized with maximum and minimum measures and three approaches were used to calculate the index. In order to put index into practice, data collected from eleven Association of Southeast Asian Nations (ASEAN) countries. Comparison was performed by al-Haji index which has been development for ASEAN countries in 2007. The findings indicated that weighted index results based on previous experience are similar to al-Haji index and correlations between them are statistically significant (r=0.997). This study showed a remarkable difference between some selected countries. Singapore and Brunei have the best index records, Malaysia, Thailand, Philippines have the medium index records, Iran (with score 36.81), Indonesia, Myanmar, Cambodia, Vietnam and Laos have the least index records. Findings of study indicate that Iran needs implementation composed index of risk factors to prevent RTIs and to assess better performance on road safety. The road safety in our country is still far from the desired condition; therefore, more attention is necessary to be done to reduce injury and mortality rates in Iran.

oxygen free radicals have been implicated as mediators of tissue damage in RA patients. This study was aimed to find the effects of vitamin A, C and zinc supplementations on oxidant–antioxidant, inflammatory and clinical indices in inactive RA patients.

We designed a randomized controlled trial. Forty nine (49) patients were randomly allocated in two groups; group I received their conventional treatment plus 300 mg vitamin C, 5 mg Zinc daily and 25000 IU vitamin A every other day for 12 weeks, group II received their conventional treatment only for the same duration. Disease activity (using the rheumatoid arthritis disease activity index (RADAI) score), biochemical indices [malondialdehyde (MDA), total antioxidant capacity (TAC)] and inflammatory markers [erythrocyte sedimentation rate (ESR), c-reactive protein (CRP)] was evaluated before and after 12 weeks.

Serum concentration of MDA and RADAI score (P<0.0001) and ESR (P=0.033) were significantly decreased and TAC levels (P<0.0001) were significantly increased in the first group in comparison to second group after 12 weeks. However, there were no statistically significant differences in serum CRP concentration of two groups (P>0.05).

This study indicates that adding antioxidants as supplementations with conventional medications in inactive RA patients plays an important role in improving oxidative stress and decreasing disease activity and inflammatory status.

A growing body of literature suggests that healthy and well-nourished women can safely participate in most forms of physical activity during pregnancy. The objective of this study was to determine the performance of pregnant women about exercise during pregnancy in Tehran.

we performed an analytical cross-sectional study on 400 pregnant women referred to prenatal care units in Imam Khomeini hospital. Information was obtained through a questionnaire designed to measure practice. Data analysis was performed by the Spss v 13.5 software package. We calculated means and standard deviation for practice in terms of independent variable and applied ANOVA test and regression model for detection of association between variables.

The mean of practice scale was (14.23+/- 1.76). We observed significant association between performance of pregnant women regarding exercise and their occupation, education status and education status of their husbands (P<0.001).Education status of husbands had a significant predictive effect in regression model (p<0.001).

It seems that the majority of pregnant women, who exercise during pregnancy, do not follow the principles correctly therefore their performance is not adequate almost in all domains.

The trend of stunting indicates of long term health status and the efficacy of different health interventions for chronic malnutrition in children. The objective of this study was to investigate the trends of stunting prevalence in preschool children living in rural area of Robat-Karim. The method of Age-Period-Cohort analysis was utilized. Existing height data of all children whom registered in health houses of Robat-Karim health network were converted to Standard Deviation Scores (SDS) using Anthro2005 software; The SDS≤ -2 for height-for-age was defined to be the moderate/severe forms of stunting. Age-Period-Cohort analysis was done with two graphical and statistical methods. The statistical method was based on logistic regression modeling in which stunting was assumed to be the dependent variable and age, birth cohort and time period were independent variables. Growth data of 970 (51.9%) boys and 898 (48.1%) girls were analyzed. The overall stunting prevalence was estimated 8.0%. This estimation by Logistic regression models (P<0.001) and graphical analyses were similar and showed that the prevalence of stunting has a decreasing trend in different birth cohorts and time periods. The prevalence of stunting was higher in the 2nd and 5th-6th years of life. The stunting prevalence was significantly higher in boys (9.3%) and non-Iranian children (9.5%) (P<0.001). The prevalence of stunting appears to be decreasing in the investigated population. Appropriate interventions is thought to be essential for reducing stunting of 2nd and 5th-6th years of life, boys, and non-Iranian children.

Work-related Musculoskeletal Disorders (WMSDs) seen more in workers of manufacturing industry than others. This study was, therefore, conducted to determine prevalence rate of WMSDs symptoms among workers of a metal manufacturing industry in Shiraz. In this study, nearly 50% of workers of the production units were randomly selected from corresponding list of each unit. Totally, 156 workers participated in this study. A self-administrated questionnaire was used to collect required data. T-test and Chi-square tests were used to analyze the data. The results showed that WMSDs occurred in considerable rate among the workers such that 76.9% of the workers studied suffered from some kind of symptoms during the last 12 months. The highest prevalence was reported in the lower back (54.5%) and knees (42.9%). Machine operators and welders reported the highest rate of symptoms. Statistical analyses revealed significant association between age, height, work tenure, weekly work hours, smoking, shift work and the symptoms (P<0.05). WMSDs symptoms occurrence was prevalent among workers of this industry. To prevent WMSDs symptoms, more attention should be paid to working conditions of the machine operators and the welders, and risk factors for back and knee regions should be reduced.

Cigarette smoking is the one of unhealthy behaviors in human societies which it’s over increasing prevalence, particularly among students, has produced many concerns. The present study seeks to describe the scale of cigarette smoking attitude (CSA) and its correlation with social determinants among high school students in the Ghaemshahr city. This cross-sectional study is conducted via survey method and data has been collected through a self-administered questionnaire. The subjects of the study were 400 third-grade students of Ghaemshahr city’s high schools who have been selected randomly on the basis of proportional stratified random sampling method. A self-administered questionnaire with 32-items including cognitive, emotional, and behavioral aspects of CSA applied. 82.6 percent of students reported negative CSA (anti-smoking), while 5.6 percent of them declared positive CSA. Descriptive results showed that students’ awareness about negative effects of cigarette smoking was relatively low and insufficient. Furthermore, the results of the Analysis of Variance (ANOVA) showed that there were significant correlations between having positive CSA and subject of the study in high school, level of father’s education, social class of the family, and especially having smoker friends and parents. It is concluded that students had low awareness and information about negative effects of cigarette smoking therefore more educational interventions should be implemented in high schools to increases the awareness and change their attitudes, Moreover, it should be emphasized that social environment, especially family and peer group (friends), play vital role in the formation of positive CSA and finally cigarette smoking.