Iranian Journal of

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Background & Objectives: Multiple Sclerosis (MS) is the most prevalent autoimmune disease of the nervous system in young adults. There are currently more than 30000 cases in Iran and the number is increasing everyday.The objective of this study was to measure the amount of vitamin and mineral intake in MS patients and to compare it with reference values.
Methods: We randomly selected 108 relapsing-remitting MS patients from the Iranian MS society in Tehran in 2005. Two questionnaires- covering personal information and medical data- were filled for each patient. Food intake was assessed by three 24-hour recalls and a quantitative food frequency questionnaire for the year preceding the study. The food intake recorded on the original questionnaire was changed to values in grams using “Manual for Household Measures” and then converted to corresponding amounts of nutrient ingredients by the “Nutritionist 3” program. Data analysis was performed by the SPSS software package. We calculated means and standard deviations for intake levels and applied t tests to compare the results with reference values.
Results: Women with MS took excessive amounts of vitamin A and vitamin C, while their daily intake of folate, vitamin E, vitamin D, magnesium, iron, zinc, iodine and calcium was below reference values. Male patients had higher-than-recommended intake of vitamin A, phosphorous, manganese and iron. Their ingestion of folate, Vitamin D and E, magnesium, zinc, calcium and selenium was shown to be below the recommended amount.
Conclusions: In view of these results, higher intake of vitamin D and calcium is recommended. Women should be encouraged to take more iron and folate as many symptoms of anemia mimics MS symptoms. Considering the well-known role of oxidative stress in the pathogenesis of MS, men should be urged to increase their ingestion of antioxidant-rich foods. It appears that nutritional assessment, dietary counseling and education are necessary for Iranian MS patients.

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Background & Objectives: Typhoid fever has been endemic in Iran throughout its history. This Study was conducted in response to the rising number of cases reported from Rasht (capital of Gilan province in northern Iran).
Methods: we performed a descriptive study on 2031 suspected cases referred to city's diagnostic laboratories in 2002 and 2003. A "definite" diagnosis was defined as Vidal test titers rising 80-fold or more over a period of one week, or a positive bacteriologic test. We completed questionnaires for the definite cases, and used the EPI-INFO computer package to analyze the data.
Results: The serologic prevalence was 3.94%, and 25% of the seropositive individuals had positive bacterial cultures. The geometric mean of the reciprocal titers (GMRT) was 1: 180. The prevalence was the same in both sexes and among all age groups. Factors showing a statistically significant relationship with prevalence include occupation (the greatest frequency was seen in housewives), education level, place of residence, and source of drinking water.
Conclusions: We conclude that high prevalence rates coupled with the ecological conditions in this area could favor the occurrence of salmonellosis outbreaks: the issue requires more extensive research for further clarification.

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Background and objectives: There is growing interest in assessing gene-environment interaction in the course of case-control studies. Difficulties related to the sampling of controls have led to the development of a range of non-traditional methods that do not require controls for estimating gene-environment interaction. One of these new modalities is the case-only approach, in which the assessment of gene-environment interaction is based on information from the cases only. The present article describes the application of this approach to data from breast cancer patients and compares its efficacy with that of a traditional case-control analysis.
Methods: We used age at first pregnancy, number of live birth, menopause and the total number of post-menopausal years as the "environment" factors and family history of breast cancer as the "gene" factor. We computed standard errors, 95% confidence intervals and (-2 log likelihood) to compare efficiency between case-control and case-only analyses.
Results: We observed significant interaction between menopause and family history of breast cancer by both methods (OR=4.32 CI: 1.10-16.90 for case-control analysis & OR=3.40 CI: 1.17-9.87 for case-only analysis). There was also a significant interaction effect between total years after menopause and family history of breast cancer (OR=1.07 CI: 0.98-1.16 in case-control analysis & OR=1.07 CI: 1.01-1.12 in case-only analysis). The case-only approach yielded narrower confidence intervals for the odds ratio, and the (-2 log likelihood) values computed by this method were correspondingly smaller.
Conclusions: Comparison of confidence intervals and (-2 log likelihood) values shows that the estimation of gene-environment interaction in breast cancer would be more efficient with the case-only approach than with the traditional case-control analysis.

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The term "health inequalities" is not a descriptive one: it refers to discrepancies in morbidity and mortality, life expectancy, disability life adjusted years, etc that are due to differences in such factors as socioeconomic status, gender and race/ethnicity. Socio-economic inequalities are the differences in health status (e.g. disease prevalence and incidence rates) across various socio-economic groups. In Europe, measuring socio-economic health inequalities has long been a major research topic. However, there have been relatively few experimental studies in Asia, especially in developing countries. In the social context, measurement of socio-economic status is based on income, educational level and employment status. Stratifying the socio-economic groups based on a hierarchy identifies the pattern of morbidity and mortality in each socio-economic stratum. It also shows the exact relationship between socio-economic status and health. The main data sources for determination of population health status and measuring health inequalities are registries and cross-sectional surveys. It seems that monitoring, prevention and evaluation of health inequalities, especially with a focus on socio-economic level has been neglected in developing countries, including Iran. Due to the lack of formal registries on population health status in these countries, designing cross-sectional and population-based studies would be a useful approach in the prevention and monitoring of health inequalities.

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Background & Objectives: Iron is a major essential micronutrient during pregnancy and has an important role in intrauterine fetal growth and safe delivery. This survey was designed to study the status of anemia, iron deficiency and iron deficiency anemia in pregnant Iranian women. The results can help health policy-makers with the design and implementation of targeted strategies to overcome these problems.
Methods: This cross-sectional study involved 4368 women at gestational ages ranging from 6 to 9 months. Subjects were drawn through cluster sampling from 11 different regions of the country. Hemoglobin (Hb), hematocrit (Hct), mean corpuscular volume (MCV) and serum ferritin levels were measured and the prevalence of anemia, iron deficiency and iron deficiency anemia (IDA) was determined both nationwide and separately in each region.
Results: Overall, 21.5% of the women suffered from anemia 42.7% were iron deficient and the prevalence of IDA was found to be 10.4%. The prevalence of anemia s was significantly greater in rural areas than in urban settings (22.2- 27.8% compared to 17.1 -21.6%, 95%CI). The highest prevalence of anemia and low Hct was seen in the women of region 5 (including Sistan and Baluchistan, South Kerman and South Khorasan with rates of 44.2% and 40.5% respectively). Region 6 (covering Isfahan, Yazd, Kohkilooyeh-Boyerahmad and North Kerman) had the lowest prevalence of anemia and low Hct (9% and 10.8% respectively). Use of iron supplements (even irregular) had a positive effect in reducing anemia. It affected Hct levels only when taken regularly.
Conclusions: Anemia is still a major health issue for pregnant Iranian women. Although supplementation should be continued, there is a need for more comprehensive interventions addressing all target groups, especially women of child-bearing age.

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Background & Objectives: Multiple Sclerosis (MS) is the most prevalent autoimmune disease of nervous system in young adults. The current number of diagnosed cases in Iran is above 40000 and is steadily increasing The objective of this study was to assess the daily macronutrient intake of MS patients and to compare this with reference values.
Methods: We randomly selected 108 relapsing-remitting patients were randomly from the Iranian MS society in 2005. Two questionnaires containing personal and medical information were filled for each patient. We assessed food intake by three 24-hour recalls and a semi-quantitative food frequency questionnaire dealing with intake over the past year. Using the Manual for Household Measures, the data were changed to values in grams and then turned to nutrient ingredients by applying Nutritionist-3. Data analysis was done using the SPSS package: m mean and standard deviation were computed for each nutrient and t tests were run to compare the figures with reference values.
Results: MS patients living in Tehran had a dietary intake of total fat, saturated fat and protein higher than recommended, while their intake of fibers was below the reference values. The body mass index was subnormal in 14.8% of the patients and above normal in 38%.
Conclusions: In light of the current pattern of macronutrient ingestion in MS patients in Tehran, a lower intake of total and saturated fat, consumption of vegetable proteins instead of animal protein and more dietary fiber are recommended. To meet this goal, vegetables, fruit, whole grains and beans are good suggestions. It seems that Iranian MS patients need nutritional assessment, counseling and education to improve their diet.

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Background & Objectives: For those with a chronic illness, suffering may result not only from physical limitations, but also from the psychosocial consequences of having a chronic condition. Therefore, simply measuring physical health is not enough anymore. It is necessary to evaluate quality of life as an important clinical outcome in these patients. We conducted the present study to measure quality of life (QoL) in multiple sclerosis (MS) patients and its predictors in comparison with the general population in Tehran, using a generic and overall QoL instrument, the WHOQOL-BREF (World Health Organization Quality of Life-BREIF). This questionnaire comprises four domains including physical health, mental health, social relationships, and environmental health. For each domain, scores range from 4 to 20, higher scores corresponding to a more favorable QOL.
Methods: This study was of cross-sectional type and involved 145 selected systematically patients registered in the Iranian Multiple Sclerosis Society. The WHOQOL-Questionnaire was filled in for these patients through telephone interviews. The results were compared with quality of life scores from the general population obtained from a population-based study in Tehran. Multiple regression was used for data analysis.
Results: The response rate was 97% 73.8% of participants were female, the mean age of participants was 36.5 (SD = 10.4) years, and the mean years of their formal education was 12.5 (SD=3.6). Mean scores for physical health, psychological health, social relationship and environmental health were 11.5 (SD=3.2), 11.8 (SD=3.2), 12.7 (SD=3.1), and 11.5 (SD=2.7), respectively. In comparison with the general population, the patients' scores in all domains were significantly lower than in the general population. Severity of disease and education level had a relationship with domain scores in regression analysis.
Conclusions: The WHOQOL-BREF questionnaire can discriminate between these patients’ quality of life and that of the general population and show the effect of disease severity and demographic variables on quality of life. Therefore the questionnaire can be used in this group of patients, although it may be necessary to add some specific questions to make the tool more sensitive in evaluating quality of life from a clinical perspective. Educational interventions are recommended to improve quality of life in this group of patients.

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Background & Objectives: The widely differing casualty rates in earthquakes of similar magnitude indicate a need for assessing the factors that determine the extent of damage to life and property. The present study looks at the structural factors and individual characteristics that had an effect on the risk of death and injury directly caused by the December 2003 earthquake in Bam.
Methods: The study population consisted of the residents of Bam on the 19th and 20th days after the earthquake of December 25, 2003. Using a cluster sampling method based on geographic location, we selected 420 households for study and asked them for information on the family members who were inside their houses at the time of the quake. The information covered the following range of items: occurrence of death or injury leading to ambulatory treatment or hospitalization, and characteristics of the building. We used logistic regression and the software package Stata 8.0 for data analysis.
Results: A total of 2089 individuals, including 1089 men (52.1%) and 1000 women (47.9%) took part in this study. There were 369 cases of death (17.7%, 95%CI=12.6-17.8%), 122 injuries needing hospitalization (5.8%, 95%CI=4.5-7.1%), and 319 cases of injury treated on an ambulatory basis (15.3%, 95%CI=12.6-17.8%), all as a direct result of the earthquake. Factors associated with increased risk of death were building destruction (OR=6.34, 95%CI=3.56-11.29), living in adobe structures (OR=1.87, 95%CI =1.03-3.4), age under 6 years (OR=3.93, 95%CI=2.17-7.11) and age 56-65 years (OR=2.52, 95%CI=1.23-5.15). Risk factors for injuries were the same as for death, with the notable exception of the building material.
Conclusions: This was the first analytic study of the risk factors for earthquake-related deaths in Iran. It revealed that total building destruction, residing in houses built with non-resistant materials, and extremes of age are significant risk factors for death in an earthquake. As for injuries, the risk factors were total building destruction and extremes of age.

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Background & Objectives: To determine the prevalence of HBV infection in the Golestan Province (southeastern part of the Caspian littoral, Iran).
Methods: A single cluster study was conducted in 2005, based on a sample of households, representative of the population aged 25-65 years in Golestan. All participants were invited for face-to-face interviews to gather demographic data. Blood samples were drawn and analyzed for serum markers of HBV infection such as HBsAg and HBcAb by the ELISA method. Factors associated with hepatitis B seroprevalence were analyzed using SPSS13 and STATA /8.
Results: A total of 1850 subjects were screened. The age- & sex-standardized prevalence for HBsAg positivity was 9.7% (95%CI=0.07-0.11). Rates were higher in males than in females (10.8% vs. 8.6%) (OR=1.28 95% CI=0.9-1.7). HBV seroprevalence in unmarried individuals was significantly higher than in those who were married (OR=2.13 95%CI=1.29-3.5). HBsAg(+) status was more frequent in urban areas (OR=1.46 95% CI=0.9-2.3). Thirty-six percent of population was HBcAb positive. HBcAb(+) prevalence was significantly higher in females (OR=1.46 95% CI=1.19-1.8) and married people (OR=1.58 95%CI=1.02-2.45), and also in urban areas (OR=1.34 95% CI=1.09-1.6).
Conclusions: This study shows that the prevalence of HBsAg(+) status in the Iranian province of Golestan is at a level regarded as "high" by the World Health Organization. It is higher than reported by pervious studies in Iran so it is important- especially for health providers and policy makers- to recognize risk factors and design appropriate prevention programs.

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Background & Objectives: Job stress is common among different groups of professionals. It might be regarded as a defensive reaction allowing the individuals to cope with negative inputs and risk factors. Because of the rise in the mass production of motor vehicles in Iran over the last 2 decades, many managers in the car industry describe their jobs as highly stressful. However, there have not been any studies in Iran on the pattern of job stress in these managers. The aim of this study was to outline the epidemiologic pattern of job stress among managers of car companies in Iran.
Methods: This study was carried out among 496 managers of car industry in Iran. Using 12 different instruments the job stress of subjects was assessed. The main domains employed to assess job stress were time pressure, scheduling and timing, management at work, decision-making at work, organizational roles, development and structure, communication at work, work condition, and interaction between work and home duties.
Results: The mean age of subjects was 43.6 years with 12.1 years of job experience (SD=7.7). All subjects were males and 95% were married. The prevalence rate of job stress among subjects was 49.5%. The top four stressors were from decision-making at work (99.1%), time pressure (97.3%), time-table and scheduling (73.5%), and management at work place (50.5%). The prevalence of job stress was more common among the managers of lower level, and the younger ones (P<0.001). However, there was no significant difference by marital status and educational attainments.
Conclusions: This study showed that the Iranian managers working at car manufacture companies are at a higher risk of job stress and its effects compared to other managers in developed countries. Job stress may play a part in making them vulnerable to illness. It should be recognize as a priority of occupational health in this community. Stress management and appropriate interventions needs to be employed to control the negative effects of job stress among this group of managers.

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Background & Objectives: Pediculosis is a ubiquitous and contagious parasitic dermatosis. Throughout the world, infestation by the head louse (Pediculus humanus capitis) is more common among schoolchildren, especially in those aged 6-11 years. This descriptive/analytical study was carried out in 2003 to determine the prevalence of pediculosis capitis and risk factors involved in the epidemiology of pediculosis in primary school pupils in Amlash, Gilan province.
Methods: The children were selected by cluster random sampling of schools and classes, and then examined for head lice using hair conditioners and a fine-toothed head lice comb. We screened a total of 4244 pupils from 95 primary schools. We used a comprehensive questionnaire to evaluate the effects of school type and location, education level, parent job, regular baths, number of persons sharing the same bed, combing frequency, host sensitivity, family size, hairstyle, gender, and hair length.
Results: Statistical analysis using χ2 tests showed that school type, school location, parent job, regular baths, number of person who share the same bed, frequency of combing, gender, host sensitivity, family size, and hairstyle are significantly associated with infestation. Infestation rate showed no correlations with hair color, season, age, or education level. Results showed that pediculosis is more prevalent in rural than in urban areas. The average rate of infestation for the area was 9.2%, indicating an epidemic situation by standard criteria.
Conclusions: The high prevalence of P. capitis infestation among these children was probably due to poor environmental hygiene and scarcity of water. Hygienic controls of schoolchildren by nurses are important for elimination of Pediculus humanus capitis. This is the first community-based study describing in detail the epidemiology of head louse infestation in the Amlash district of Gilan province in Iran and confirms that Pediculosis capitis is still a problem in many environments, particularly those with low life standards and poor health care.

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Background & Objectives: There are near two million people from around the world have planning to journey for Hadje ceremony. Old age, Crowding dormitory, close contact, poor sanitation, poor health services, different community pattern, high temperature and other factors cause the infectious diseases particularly respiratory infection more than ever Influenza occur more common and cause more discomfort during this ceremony. This study in 1381 Clear the effect of influenza vaccine compare with placebo in this group of population Pilgrimage group.
Methods: This study had interventional randomize clinical design on 156 pilgrims in Abhar City. The pattern of the cases selection for reducing of bias effect was every other pilgrim for vaccine injection. All of the cases before, during and three week after return back from this ceremony had close health services. All the pilgrims had private document for recording the events.
Results: About 147 of pilgrims experienced had pulmonary infection (93% in case and 96% in control). There was no difference in either cases or control groups
Conclusions: There is no benefit for using influenza vaccine other than its indications in the patients but it needs additional studies.

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Background & Objectives: Tobacco smoking is known to cause a huge burden of disease throughout the world: smoking is responsible for 4 million deaths per year. This study is performed in order to fill the existing gaps in information regarding current trends for lifestyle and tobacco-related disease in Iran.
Methods: This was a cross-sectional study performed with the help of a questionnaire and using a multi-stage cluster sampling method. The final sample size, after the screening of the data, was 84706 out of 89457 records.
Results: From a total of 84706 people in this study, 49.7% were men, 52% were uneducated and 64.8% cane from urban areas 79.9% did not smoke, 15.3% smoked actively, 2.1% were non-active smokers and 2.7% were ex-smokers. The prevalence of smoking was higher in people aged 35 to 64 years (P<0.001). Quitting rates increased with age, especially in women (P<0.001). Smoking was more prevalent in men (P<0.001) and in rural areas (P<0.001). The average number of cigarettes smoked per day was 14.69. Smoking prevalence was lower among adults with higher levels of education compared to those with lower education levels (P<0.001).
Conclusions: This nationwide survey provides a baseline for future longitudinal studies of smoking in Iran. There is a need for effective smoking prevention and cessation programs with a focus on the young population.

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Background & Objectives: Early detection can improve the outcome of visual impairment in children, and one method for early detection could be screening of pre-school children with visual acuity tests. The aim of this study was to determine the validity of these tests when they are used on children entering grade school.
Methods: For this cross-sectional study we drew 39 random clusters, comprising a total of 5721 school children. We then used 2158 student files to extract data on tests of vision performed by school health officers and compared these data with data generated by optometrists. Measurement of uncorrected visual acuity was done with the E Chart by both teachers and optometrists.
Results: The sensitivity and specificity of teacher-administered tests were 25.0% and 96.6%, yielding positive and negative predictive values of 13.4% and 98.4%, respectively. Sensitivity and specificity rates did not show any significant difference between male and female populations (P=0.356, P=0.258), but the difference between specificity in urban and rural areas was significant (P<0.001).
Conclusions: Screening tests for visual impairment did not attain the desired level of sensitivity or specificity for case detection in school children. More accurate procedures are required to minimize the number of false negative results.

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Background & Objectives: Cancer has been traditionally regarded as a fatal disease it is a major public health problem in many countries throughout the world. In recent years, cancer morbidity and mortality has increased in our country and notably stomach cancer now ranks second or third among all cancers types with regard to morbidity.
Methods: Our study included all gastric cancer patients registered in the cancer registry of Fars province. The patients' survival status was followed using phone calls and death records from hospitals, other medical centers, and the city's cemetery. Data analysis involved the use of the nonparametric Kaplan-Meier and Cox proportional hazards models and was performed with the software package SPSS V.13.
Results: Of the 442 patients with gastric cancer, 303 cases (68.6 percents) were male, and the mean age of patients was 58.41 years (SD=14.46). In univariate analysis with the KM method, a statistically significant association was found between survival rates and the following factors: age at diagnosis (P<0.001), tumor grade (P=0.009), presence of metastases (P<0.001), and type of the initial treatment (P=<0.001). Factors without a significant relationship with the survival rate included sex, ethnicity, weight, BMI, tobacco use, history of cancer in close or distant relatives, place of residence, number of children, marital status, occupation, and income. In Cox regression, only age at diagnosis, tumor grade, and the presence of metastases showed a significant association with survival rates.
Conclusions: Our results imply that early detection of cancer at a lower age and in lower tumor grades could be important for increasing the patients' life expectancy.

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Background & Objectives: Although Cox regression is commonly used to detect relationships between patient survival and demographic/clinical variables, there are situations where parametric models can yield more accurate results. The objective of this study was to compare two survival regression methods, namely Cox regression and parametric models, in patients with gastric carcinoma registered at Taleghani Hospital, Tehran.
Methods: Using data from 746 patients who had received care at Taleghani Hospital from February 2003 through January 2007, we compared survival rates between different patient groups with both parametric methods and Cox regression models. The former group included Weibull, exponential and log-normal regression we used the Akaike Information Criterion (AIC) and standardized parameter estimates to compare the efficiency of various models. All the analyses were performed with the SAS software and the level of significance was set at P< 0.05.
Results: The results showed a significantly higher chance of survival in the following subgroups: those with age at diagnosis < 35 years, lower tumor size and those without metastases (P< 0.05). According to AIC, Cox and exponentials model are similar in multivariate analysis but in univariate analysis parametric models are more efficient than Cox, except in the case of tumor size. Log-normal appears to be the best model.
Conclusions: Cox and exponential models have similar performance in multivariate analysis. However, it seems that there is no single model that performs substantially better than others in univariate analysis. The data strongly supported the log-normal regression among parametric models it can give more precise results and can be used as an alternative for Cox in survival analysis of patients with gastric cancer.

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Background & Objectives: To determine the risk factors for acute diarrhea disease in children.
Methods: This study involved 220 cases and 220 controls in Dr. Sheykh Hospital, a specialzed pediatric hospital in Mashhad. Cases were children seen in the emergency department with loose watery feces, diagnosed as acute diarrhea by the physician. The controls were selected from the same setting as the cases and included children with traumas, burns, acute respiratory complaints and other diseases.
Results: In univariate logistic regression, variables having a significant relationship with acute diarrhea disease included formula feeding in the first 6 months of life, antibiotic therapy over the preceding 15 days, mother's employment, mother's acquaintance with oral rehydration solutions, place of residence, and disruption in the water supply in the week before illness. We performed multiple logistic regression to examine the role of these variables as independent risk factors for acute diarrhea. Use of formulas before 6 months of age (OR=3.21, 95%CI: 1.77-5.79), and type of residence (OR=1.83, 95%CI: 1.24-2.71), and mother's employment (OR=2.48, 95%CI: 1.2-5.06) were the factors that remained in the multiple logistic model and had a significant relationship with the disease.
Conclusions: This study identified some environmental risk factors for acute diarrhea disease. High-risk groups and mothers of children under 5 years of age should be aware of these risk factors in order to prevent disease in their children. Prevention of acute diarrhea in children can significantly reduce the current burden on the health system.

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Background & Objectives: There is little doubt about the importance of accurate statistics and reliable information in the promoting community health and optimizing health care. Therefore, the existence of a correct, accurate and up to date database is an absolute necessity. Accurate identification of the cause in death certificates can make an invaluable contribution to the development of such a database. The purpose of this research was to assess the current defects and shortcomings in death certificates and to evaluate the degree of agreement between the diagnoses recorded in hospital files those figuring on death certificates.
Methods: This was an analytic cross-sectional study. In this survey of 659 medical records of dead patients in Loghman Hospital, during 2005, 290 medical records were selected using a systematic sampling method. The selection of these records were based on record numbers in the archives and involved the extraction of the following data: the physician's field of specialty, the patient's identity, code for the main diagnosis, the code for the external cause on the admission form, and the code for the cause of death on the death (as defined in ICD-10) was recorded. The agreement between primary and final diagnoses and also the agreement between final diagnosis and the cause of death were assessed in relation with the physician's specialty using Fisher's Exact Test. Overall agreement between different diagnoses was measured using the kappa statistic.
Results: The degree of agreement between primary and final diagnosis was very good (k = 0.83) and agreement between final diagnosis and cause of death was excellent (k = 0.95). Fisher's exact test showed that agreement between primary and final diagnoses and between final diagnoses and cause of death doesn't depend on the physician's specialty (in both cases p>0.01). In 62% percent of the cases death had occurred without interference from an external cause. Among the 38% in which there was an external cause, 21% involved poisoning with suicidal intent, 12% were due to accidental poisoning, 4% were motor accidents, and 1% were due to other reasons.
Conclusions: There was a high degree of agreement between different diagnoses in some specialties, while didn't observe such agreement in other specialties. Since accurate diagnosis helps in identifying the cause of death and death information is an important indicator of health at community level, we recommend that physicians pay greater attention to accurate recording of the cause of death. This will make it possible to draw meaningful comparisons between the causes of death in Iran and those in other countries.

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Background & Objectives: The summer of 2005 witnessed an outbreak of cholera in Iran due to V. cholera, Inaba serotype. During the outbreak, there were 16 registered cases in Markazi Province. The aim of this study was to determine the risk factors for cholera outbreak in this part of the country.
Methods: This was a case-control study in which cases were matched to controls on age and sex. All of the reported cases were compared with controls from the same neighborhood, with 2 controls selected for each case. We used paired odds ratios and conditional logistic regression to show the effect of each putative risk factor, and p values of < 0.05 were considered as statistically significant. Results: Multivariate results from 16 cases and 32 controls showed significant associations between the cholera outbreak and the following set of factors: eating raw vegetable (OR=9, 95%CI: 2.25-35.98), proper warming of refrigerated food (OR=0.12, 95%CI: 0.015-1.022), inadequate washing of fruits and vegetables (OR=4.29, 95% CI: 0.88-21.06) , and eating non-pasteurized ice creams (OR=4.96, 95%CI: 0.99-24.83).
Conclusions: Although the number of reported cases was small in Markazi Province, the results show that education in personal hygiene is important in the prevention of a cholera outbreak.

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Background & Objectives: Recent evidence suggests that long-term exposure to air pollution contributes to progression of atherosclerosis and the risk of cardiac morbidity and mortality short-term exposure may also lead to thrombosis and acute ischemic events. To evaluate the relation between the levels of major air pollutants (CO and PM10) and hospital admission for acute coronary syndrome (ACS) in Tehran, we performed a case-crossover design and checked whether individual characteristics act as effect modifiers.
Methods: We selected 250 Tehran residents who had been hospitalized with an acute coronary syndrome from 4th of April to 10th of June, 2007. The following individual data were gathered: sex, age, date of hospitalization, and coexisting illnesses (hypertension, diabetes). Daily air pollution data were taken from the Air Quality Control Center. Temperature, humidity, stress, physical activity and weekend days were treated as confounding variables, and a conditional logistic regression model was used for statistical analysis.
Results: We found a positive association between ACS and average 24-hour CO levels. The OR for each unit increase of the average 24-hour CO was 1.18 (95%CI: 1.03-1.34). The relation between ACS and 24-hour average PM10 did not reach statistical significance (OR for average 24-hour PM10 was 1.005, 95%CI: 0.99-1.01). The association between ACS and 24-hour average CO tended to be stronger in women (OR=1.68 for each unit increase, 95%CI: 1.25-2.26). The relation between 24-hour average PM10 and ACS did not change across the layers of the effect modifiers.
Conclusions: The results suggest that an increase in average 24-hour CO levels will augment the risk of ACS, and the effect is stronger in females. On the other hand, we were unable to document an association between ACS and average 24-hour PM10 levels.