Iranian Journal of Epidemiology

Estimation of the Attributable Burden of Colorectal Cancer in Iran in 2008

P Yavari

Background and Objectives: Colorectal cancer, as the third common cancer, is one of the main health problems in Iran. We assessed the burden of colorectal cancer, as one of the high-priority indices, in this cross-sectional study in Iran in 2008.

Methods: CANMOD software was used for calculation. The input data included the population of Iran, all-cause and colorectal cancer mortality rates, and incidence rate of colorectal cancer, which were all obtained from the Iran Statistic Center, Mortality Registry System, and Cancer Registry System.

Results: The total burden of colorectal cancer according to DALY in Iran in 2008 was 52534 years in the total population. Years of lost life (YLL) amongst males and females were 26455 and 19887 years, respectively. Years lived with disability (YLD) were 3473 and 2719 years for males and females, respectively. The burden of colorectal cancer per 1000 population was 75.4 years for males and 65.7 years for females. The peak age of colorectal cancer burden rate was in the age group 45-79 years.

Conclusion: The burden of the colorectal cancer in Iran has increased compared to the last study (2003) which is due to the increase in its incidence and the related mortality during this period. Due to the possibility of prevention and effective intervention, this cancer should be a priority in the health care system. However, the final judgment should be made after calculation of the burden of other cancers, diseases, and damages at the country level and their respective rankings.

The Risk of Chronic Kidney Disease and Metabolic Syndrome in the Incidence of Coronary Heart Disease: Tehran Lipid and Glucose Study

P Yavari

Background & Objectives: We studied the risk of Chronic Kidney Disease (CKD), Metabolic Syndrome (MetS), and their interaction on the incidence of Coronary Heart Disease (CHD).
Methods: A population of 6568 participants (43.4% male) with a mean age of 48.4 years for males and 46.7 years for females and a median follow-up of 10.1 years was investigated. They were divided into 4 groups at baseline: CKD-/MetS-, CKD+/MetS-, CKD-/MetS+, CKD+/MetS+. Hazard Ratios (HRs) were calculated for each group and were compared to the first group using multivariate Cox regression analysis adjusted for age, education, smoking, total cholesterol, and the family history of cardiovascular diseases.
Results: Men with CKD (without MetS) showed an HR of 1.74 (CI 95%: 1.16-2.60) for CHD events. The measured value was 2.34 (1.77-3.08) for men with MetS (without CKD). The respective results were in women 1.18 (0.64-2.19) and 2.59 (1.73-3.88). CKD and MetS had a significant negative interaction with CHD events (HR=0.40, 0.24-0.66). The interaction was not significant in women (P value=0.48).
Conclusion: The results of this study indicated that CKD without MetS was a risk factor for coronary heart disease in men but not in women.

Comparison of the Results of Case-Cohort Study with Cohort Study on Assessing the Relationship between Diabetes and Cardiovascular Diseases: Tehran Lipid and Glucose Study

B Eshrati

Background & Objectives: The case-cohort study is one of the youngest designs in epidemiology and some methodological aspects of it are still in debate. This study aimed at comparing the estimated hazard ratio, standard error, and interaction hazard ratio between the case-cohort and cohort studies for assessing the relationship between diabetes and cardiovascular diseases.

Methods: A total of 1701 men and 2253 women aged between 40 and 75 years were considered as the main cohort. Subcohort sampling was performed using simple random sampling with a sampling fraction of 0.3%. The hazard ratio of the cohort study was calculated using Cox regression model and the 3 methods of Prentice, Self-Prentice, and Barlow were used for calculating the hazard ratio of the case-cohort study. The mentioned regression models were used to assess the interactions.

Results: The results of the two studies were similar in populations with higher incidence (cohort of men) and lower incidence (the cohort of women) when frequency percent of exposure variable was greater than 10%. When the sample size of the initial cohort was less than 1250 subjects, discrepancies were observed between the results of the two studies. In addition, the standard error of the case-cohort study was higher than the cohort study. The results of both studies were similar in assessing the considered interactions.

Conclusion: The results are similar when the initial cohort sample sizes are sufficient. Meanwhile, unlike the percentage of exposure frequency, the outcome incidence has a negligible impact on the discrepancy between the results while the effect of the relative frequency of the exposure levels on the results discrepancy is noticeable.

Comparison of the Period Prevalence of Urban Cutaneous Leishmaniasis (CL) in Bam in Two Time Periods of 1990-1992 and 2010-2012

MR Aflatoonian

Background & Objectives: Bam is one of the old CL centers and this study aimed to determine and compare the period prevalence among its population and housing units in two periods of 1990-92 and 2010-2012.
Methods: In this descriptive–analytical study, data were collected in the questionnaires through door-to-door visits environmental hygiene, and inquiring the history of the CL disease. A questionnaire was completed for each household, the data were analyzed using SPSS software and t- and X2 tests. P<0.05 was considered significant.
Results: The prevalence rates in the periods 1998-1999 and 2010-2012 were 10.3% and 2.1%, in the study population and 33.6% and 5.5% in the residential units in the period of the last 3 years, respectively with a very significant difference (P<0.0001). The environmental hygiene of the houses in terms of vector breeding was significantly lower in the period 1990-1992 than 2010-2012 (P<0.0001). The mean score of environmental hygiene was 11.5 and 16.6 out of 20 during the two periods, respectively.
Conclusion: According to the results of this study, urban CL is extremely reflective of the environmental changes and probably the best preventive measure is to improve the environmental hygienic conditions in and around the households. Public participation and commitment of the health authorities in this regard could be an important measure for planning preventive programs.

Epidemiology of Tuberculosis in Lorestan between 2002 and 2008

J Yazdani Cherati

Background & Objectives: Tuberculosis (TB) is one of the major infectious diseases in Iran and has pulmonary and extra-pulmonary manifestations. Considering the differences in the distribution of the cases across different regions, we decided to study the geographical distribution, epidemiologic characteristics, and disease pattern in Lorestan.

Methods: This ecologic (descriptive analytical) survey was done in Lorestan between 2002 and 2008. The data was collected from the Health Department of Lorestan University of Medical Sciences and included the history of 1481 patients suffering from TB. The study variables were sex, disease type, residential location, age, and year. The data were analyzed using statistical package SAS 9.2 and descriptive and inferential statistics were applied.

Results: From 1481 registered patients 58.4% were male and 41.6% were female among which 68.74% and 29.98% lived in urban and rural areas and 1.28% were nomads. The mean age of the patients was 41.87. The highest and lowest incidence rates were observed in Khoram Abad (19.38 per 100000) and Azna (7.04 per 100000), respectively. Using Poisson regression, it was observed that the effects of age structure and residency on the incidence rate were significant.

Conclusion: The percentage of nomads was identified as the most important demographic factor in the incidence rate of TB in Lorestan. Allocation of better resources and appropriate training can be effective in controlling and preventing the disease.

Smoking and its Correlates in Male Students in South Khorasan in 2008

AA Ramazani

Background & Objectives: Smoking is a global problem and is the most important cause of death due to non- communicable diseases. This study was conducted to evaluate smoking and its correlates in male students in South Khorasan.

Methods: This descriptive-analytical study was undertaken in South Khorasan on high school male students. A sample of 2371 cases was selected through cluster multi stage sampling. The data was collected through a structured questionnaire and analyzed by SPSS software using chi-square and logistic regression tests.

Results: The prevalence of smoking was 12.3 per cent (285 cases).The most important motivating factors for smoking for the first time were curiosity, joy. The most important predictors of smoking were hookah consumption, the presence of a smoker in or outside the living place, and a negative attitude to smoking. Working father and education regarding smoking risks were preventive factors.

Conclusion: Special education and public awareness about the risks of smoking and establishment of consultation centers for adolescents can be major steps toward the prevention and control of smoking among students.

Identification of the Impact of Major Causes of Death on Life Expectancy in Fars Using the Multiple Decrement Life Table Method

M Sasani Pour

Background & Objectives: The recent researches on mortality in Iran in the past 3 decades have obviously emphasized cardiovascular diseases, unintentional injuries, and neoplasms as the most important causes of shortening Iranian’s lives. We investigated the role of these major causes on the mortality patterns in Fars in 2006.
Methods: The number of registered deaths by age and sex and the distribution of death by cause in Fars in 2006 were derived from the Death Register System of Ministry of Health (MoH). We used the 2006 census to obtain the information on the population exposed to death. The mortality of the people over 5 years of age was estimated and corrected using the Brass Growth Balance method. The mortality rate of the children under the age of 5 was estimated by indirect methods and the data were analyzed using the multi-decrement life table.
Results: Life expectancy was 70.3 years in Fars, about 69 years in males and 72 years in females, in 2006. The results showed that 3 main causes of death were responsible for reducing life expectancy of about 11 years in men and women in Fars. Detailed results revealed that cardiovascular diseases and unintentional injuries played more important roles in the decrease. Unintentional injuries plays more major role in decreasing life expectancy in males than females.
Conclusion: Special attention should be paid to the risk factors of cardiovascular diseases in both genders and unintentional injuries in males in Fars to reduce the mortality level and increase the life expectancy.

The Quality of Life and Its Effective Factors in the Elderly Living Population of Azerbaijan District, Tehran, Iran

s Zaeri

Background & Objectives: The world population is growing old. The rising proportion of the elderly is creating new health care challenges in the current century. This study aimed to determine the quality of life and the associated factors in the elderly population of Azerbaijan district in the city of Tehran, Iran.

Methods: This cross-sectional study was conducted on 287 elderly persons aged 60 and older. Participants were selected through systemic random sampling. The WHOQOL-BREF questionnaire, the Activities of Daily Living (ADL) questionnaire, and a questionnaire for demographic characteristics were used for data collection. Each domain was given a score between 0 to100 based on the WHO manual. The final variables were determined in a multivariate linear regression model using SPSS16.

Results: The mean score of the 4 domains of quality of life (physical, psychological, environmental, and social health) of the elderly population living in Azerbaijan district was 58.41, 53.13, 59.53, and 42.82, respectively.

Conclusion: A variety of correlates affect the quality of life of the elderly. Recognizing and considering these factors are important for planning more effective programs for the elderly and empowering them.

Evaluation of the Factors Associated with Overweight and Obesity in 30- to 50-year-old Women of Sabzevar

T Amiri Parsa

Background & Objectives: Obesity is associated with increased resistance to insulin, hypertension, hyperlipidemia, hyperinsulinemia, and cardiovascular diseases. The purpose of this study was to investigate some factors associated with overweight and obesity among normal, overweight, and obese women aged 30 to 50 years from Sabzevar.
Methods: A questionnaire with 56 questions was prepared. The Beck questionnaire was used to measure the physical activity level. Weight, height, and waist circumference of the participants were measured using standard methods. Overweight (BMI ≥25 kg/m2), obesity (BMI ≥30 kg/m) and abdominal obesity (WHR ≥0.85) were also evaluated. MANOVA, Tukey post-hoc test, Pearson and Spearman correlation coefficients, Kruskal-Wallis and chi-square test were used for the statistical analysis of test variables. P ≤0.05 was considered significant.
Results: The results showed that 22.5% of women had normal weight, 42.4 percent were overweight, 31.6 percent were obese, and only 3.5 percent of women were underweight.
Conclusion: Our results showed that the prevalence of overweight and obesity was 74% in women living in Sabzevar, indicating the necessity of using educational methods to familiarize people, especially women, with weight control issues and prevention of obesity. The findings revealed that age, number of children, number of pregnancies, age at menarche, number of family members, working with the computer, and high-fat meals may increase the risk of obesity. Lifestyle modification and physical activity, as the most affordable and safest methods of preventing obesity, require more attention.

The Residential Segregation Indices in Hormozgan Province Using 2006 Iranian Census Data

K Holakouie Naieni

Background & Objectives: One of the major questions in epidemiological and social science researches is studying the relationship of the living place with social and health outcomes. In this study, we measured segregation indices for a number of important socioeconomic indices using the 2006 Iranian census data to find out whether residential segregation is correlated with the available differences in the health level in the subgroups of certain variables.

Methods: Twenty percent of the 2006 national census data was used for measuring segregation indices. Residential segregation indices were measured once for Hormozgan Province among its eleven cities and then for each city among theirs sections. Six segregation indices were measured. We used the common cut points for interpreting the values of dissimilarity index and information theory index.

Results: According to the dissimilarity and information theory index, the segregation of most of the variables in the province fell within the category of mild segregation. Segregation of the variables in some cities fell within the category of moderate, severe, and even extreme. Conclusion: The results indicated improper distribution of some of these variables in geographic units in some of the cities of Hormozgan Province. This information can help the authorities who are committed to implementing the health equity and social justice.