Years of life lost due to gastric cancer is increased after Bayesian correcting for misclassification in Iranian population

Aim: To estimate the change in years of life lost [YLL] due to gastric cancer mortality after correcting formisclassification in registering causes of death using the Bayesian method

Background: For evaluating the health status of a country and determining priority of risk factors, some epidemiologicindicators are needed. Due to premature death, YLL is one of the most widely used indicators. To have an exact estimate ofYLL, an accurate death registry data is needed, but the Iranian death registry is subject to misclassification error

Material and methods: Gastric cancer mortality data from 2006 to 2010 for Iran were extracted from national deathstatistics. The rate of misclassification in registered causes of deaths was estimated, using Bayesian method for eachyear. Then YLL of gastric cancer is estimated for different age-sex categories before and after implementing Bayesianmethod

Results: Using Bayesian method, the estimated misclassification rate for gastric cancer in cancer without label group were 5%,3%, 3%, 7% and 7% respectively from 2006 to 2010. Estimated Years of life lost due to gastric cancer before correctingmisclassification were respectively 111684.93, 114957.31, 112391.93, 112250.53 and 113300.92 person-years for years 2006to 2010. After correcting misclassification, the total YLL of gastric cancer increased to 1535.19, 921.11, 908.39, 2566.39 and2507.00 person-years, respectively from 2006 to 2010

Conclusion: If health policy makers ignore the existence of misclassification in registered causes of death, they mayunderestimate the burden of some causes of death and overestimate some others

Evaluation of parametric models by the prediction error in colorectal cancer survival analysis

The aim of this study is to determine the factors influencing predicted survival time for patients with colorectal cancer [CRC] using parametric models and select the best model by predicting error's technique. Survival models are statistical techniques to estimate or predict the overall time up to specific events. Prediction is important in medical science and the accuracy of prediction is determined by a measurement, generally based on loss functions, called prediction error. A total of 600 colorectal cancer patients who admitted to the Cancer Registry Center of Gastroenterology and Liver Disease Research Center, Taleghani Hospital, Tehran, were followed at least for 5 years and have completed selected information for this study. Body Mass Index [BMI], Sex, family history of CRC, tumor site, stage of disease and histology of tumor included in the analysis. The survival time was compared by the Log-rank test and multivariate analysis was carried out using parametric models including Log normal, Weibull and Log logistic regression. For selecting the best model, the prediction error by apparent loss was used. Log rank test showed a better survival for females, BMI more than 25, patients with early stage at diagnosis and patients with colon tumor site. Prediction error by apparent loss was estimated and indicated that Weibull model was the best one for multivariate analysis. BMI and Stage were independent prognostic factors, according to Weibull model. In this study, according to prediction error Weibull regression showed a better fit. Prediction error would be a criterion to select the best model with the ability to make predictions of prognostic factors in survival analysis

Burden of gastrointestinal cancer in Asia; an overview

The cancers in the digestive system including gastric cancer, colorectal cancer, liver cancer, esophageal cancer and pancreatic cancer are one of the most common cancers in Asia. The burden of GI cancer is increasing in Asia because of aging, growth of the population and the risk factors including smoking, obesity, changing lifestyle and high prevalence of H pylori, HBV and HCV. In most Asian countries, cancer control programs or early detection and treatment services are limited despite this increase. There are many people in the developing countries inside Asia who have no health insurance and many of them are too poor to go for screening tests, early detection or medical treatments. Therefore, it is important for the health organizations and governments in each country to recognize these groups and reduce the incidence and mortality of gastrointestinal cancers, using simple and economic screening test, vaccination and changing risk factors such as smoking, diet and lifestyle by education programs

[Comparison of energy-restricted high protein [HP] with standard-protein [SP] diets in women with polycystic ovary syndrome]

Some researchers administer a diet with a higher ratio of protein to carbohydrates [HP] in patients with polycystic ovary syndrome [PCOS], but there is a limited number of dietary interventions compared the effects of an HP diet with a standard protein [SP] diet. Therefore, the aim of this review was to compare the effects of energy-restricted HP diets with those of iso-calorically prescribed SP diets on anthropometric, metabolic, hormonal, and reproductive outcomes in women with PCOS. Searches for English-language studies published between 2000 and 2014 were conducted using PubMed, Science Direct, and Scopus databases to identify all randomized controlled trials that compared HP diet with SP diet. There was no difference in anthropometric outcomes between two different diets. There was no difference in reproductive outcomes between the two dietary treatments. Weight loss decreased testosterone, free testosterone, or FAI [Free Androgen Index] and increased SHBG, independent of prescribed diet. There was no difference in metabolic outcomes between the two dietary treatments. A standard-protein weight-loss diet reduced HDL- cholesterol, while no changes occurred for a high protein weight-loss diet. The high-protein diet reduced total cholesterol to HDL-C ratio. Weight loss, independent of diet composition, decreased fasting insulin, insulin resistance and Improvements in lipid profiles. High protein diet caused subtle and inconsistent changes in metabolic variables, and weight loss results in clinical benefit, regardless of diet composition, in women with PCOS

Prognostic factors in birth time: a survival analysis

The waiting time between children births are called tempo. This phenomenon plays a crucial role in the child and mother health. The purpose of the present study is determination of factors which influence this variable of interest. A significance level of 5% and power of 80% considered to calculate the required sample size for this cross sectional study. The sample size of 124 women determined using PASS software [ver. 11.0.4]. These women randomly selected of married women between 15-45 years old with at least two children, living in Irin village. We consider the waiting time between the first and the second birth in women randomly sampled from Irin village of Tehran province of Iran. The selected mothers had 364 children at the time of study. The average and standard error for the number of children were 2.940 and 1.102 respectively. 59% of the children were girl and the rest were boy. Tempo variable as an index estimated using Toki method. The lowest tempo is for 5th to 6th births [28.5] and highest is for 6th to 7th [60]. Cox regression model was used to determine the significant explanatory factors. Birth of child was considered as an event and time between the first and the second event was considered as outcome in this model. According to the fitted Cox regression model, only maternal education and father's occupation were statistically significant at 5% on time to second birth

Leukemia cancer mortality trend in Iran, from 1995 to 2004

Cancer is the third most common cause of death in Iran, the leukemia cancer is one of the most important causes of cancer mortality. Regarding cancer mortality, data would be important to monitor the program screening effects, earlier diagnosis, demographic data and other prognostic factors. The aim of this study was mortality rates evaluating, then leukemia cancer trends among the Iranian population within almost a period of a decade, i.e. from 1995 to 2004. National death Statistic Reported by Ministry of Health and Medical Education [MOH and ME] from 1995 to 2004, stratified by age group, sex, and cause of death, have included in this study. Leukemia cancer has expressed as the annual mortality rates/100,000, in general, and/or per gender, and age group. The general mortality rate of leukemia cancer has slightly increased within the mentioned study period, from 0.44 to 2.54, then leukemia cancer mortality has often seen in men more than women. The mortality rate of leukemia has significantly increased throughout Iran. Associated risk factors with leukemia have headmost identified for their prevention and control. So, future studies to reveal leukemia risk factors among the Iranian population would be crucial in order to control its burden

effects of wrist orthosis on Hmax to Mmax ratio, spasticity, Grip and pinch strength and wrist and elbow range of motion of spastic children

Upper limb dysfunction is a common and disabling consequence of cerebral palsy. Instrumental evaluations, based on electromyography or biomechanical techniques, may objectively quantify various clinical characteristics associated with spasticity and should be considered as an adjunct to clinical evaluation. The purpose of this study was to determine the effects of wrist orthosis on Hmax to Mmax ratio, spasticity, Grip and pinch strength and wrist and elbow range of motion of 7 to 12 years old spastic children. The design of this study was clinical trial and before after. Twenty four 7 to 12 spastic cerebral palsy children that have the inclusion criteria of study were selected from rehabilitation clinics of Tehran. The patients used a wrist orthosis [10 degree of wrist extension, full extension of fingers and abduction and opposition of thumb] for 2 mounts [2 hours during day and 4 to 6 hours at night]. In this study the H-reflex was recorded using an electromyography, by an experienced physiotherapist who was blind to the clinical examination results. Spasticity of the upper limb was clinically assessed using the Modified Ashworth Scale. MIE used to evaluate Grip and Pinch strength and Goniometric measurements of elbow and wrist extension were obtained in degrees to calculate the passive range of motion. The results of this study showed significant reduction in Hmax to Mmax ratio [P 0/002], wrist spasticity and elbow spasticity [P 0/001] and significant increase in Grip [P 0/002] and Pinch [P 0/001] strength and wrist range of motion [P 0/003]. The data did not show any significance in elbow range of motion [P 0/328]. Our findings suggested that 2 months using of wrist orthosis in children with spastic cerebral palsy can reduce Hmax to Mmax ratio and wrist spasticity and increase Grip and Pinch strength and wrist range of motion

How to control confounding effects by statistical analysis

A Confounder is a variable whose presence affects the variables being studied so that the results do not reflect the actual relationship. There are various ways to exclude or control confounding variables including Randomization, Restriction and Matching. But all these methods are applicable at the time of study design. When experimental designs are premature, impractical, or impossible, researchers must rely on statistical methods to adjust for potentially confounding effects. These Statistical models [especially regression models] are flexible to eliminate the effects of confounders

[Prognostic factor for patients with gastric cancer using the Aalen's additive hazards model]

Gastric cancer is the second leading cause of cancer death worldwide and is the most common type of cancer in Iran. The objectives of this study were to assess the effects of prognostic factors on survival of patients with gastric cancer using the Aalen additive hazards model, and to illustrate the advantage of Aalen's plot. Information of total of 213 patients with gastric cancer who underwent surgery in the gastroenterology ward of Taleghani hospital in Tehran between 2003 and 2008 were included in this historical cohort study. Age at diagnosis, sex, presence of metastasis, tumor size, histology type, lymph node metastasis, and pathologic stages were entered into analysis using the Aalen additive hazard model. To visualize a covariate effect over time, the estimated cumulative regression function by the Aalen's model is examined. The univariate and multivariate analysis identified that age at diagnosis, tumor size and pathologic stage were independent prognostic factors for the survival of patients with gastric cancer [p<0.05]. Moreover, pathologic stage has a late or delayed effect according to the Aalen's plot. Other clinicopathological characteristics were not statistically significant [p>0.05]. In spite of using Cox model in survival analysis by many researchers, Aalen's model may yield new insights in prognostic studies of survival time of patients with gastric cancer over time. Our results suggest that early detection of patients in younger age and in primary stages is important to increase survival from gastric cancer

[Application of Bayes method in determining of the risk factors on the survival rate of gastric cancer patients]

Gastric cancer is one of the most common cancers in the world. The classical methods such as Cox regression and parametric models are used in most medical researches that their aims is the survival distribution survey, although the Bayes models have some advantages in compared with the classical models. The present study was performed to analyze the survival rate of patients who had gastric cancer and were under treatment in the gastroenterology ward of Taleghani hospital, in Tehran using Bayes models. Weibull distribution was used for modeling in the study. This study was a cohort study and performed in the gastroenterology ward of Taleghani hospital by using gastric cancer patient's data from January 2003 to December 2007. 178 patients were enrolled to the study and their information was collected through telephone contacts. The survival rate of patients were analyzed using Bayes Weibull models by considering variables such as age of diagnosis, gender, tumor size, metastasis of other lymph. For determining of the risk factors on the survival of patients, was used Weibull model in the case that interval censoring. Data analysis was carried out using Winbugs software and significant levels were considered 0.05. The results showed survival rate are dependent on the age of diagnosis and tumor size. Those patients who had early diagnosis, the rate of survival was greater. In addition, the patients who had smaller tumor size, their survival rate was greater. Considering to classical models are based on normal approximation and applicable for big samples, Bayes methods are emphasized for small to medium samples. The results of this study showed that the Bayesian Weibull model is a suitable model. This study also showed that age of diagnosis and tumor size of patients is important factors in regard to the survival rate of these patients. As a result, if gastric cancer is diagnosed early, the relative risk of death would reduce

Dexamethasone as a supplement for exogenous gonadotropin to improve ovarian response of women over 35 years undergoing IVF/ICSI cycles

With aging, the ovarian reserve is decreased and that is a major contributor to poor ovarian response to exogenous gonadotropins. The aim of the present study is to evaluate the role of Dexamethasone on ovarian response in infertile patients aged over 35 years undergoing IVF/ICSI cycles. In this triple blind placbo-control clinical trial study, a total of 72 infertile women over age 35, undergoing IVF/ICSI cycles, referred to Royan Institute from May 2000 to May 2002 were selected. Dexamethasone co-treatment [1mgld] was started on the 21st of their preceding menstrual cycle and it was continued until oocyte aspiration. The main outcome measures were number of retrieved oocytes, number of fertilized and transferred embryos, number of used HMG, serum E2 level on HCG injection day, and pregnancy rate. There was no significant statistical difference in age, duration of infertility, Body mass index, hormonal tests, number of retrieved oocytes and transferred embryos. However, the number of used HMG was significantly lower in Dexamethasone group compared to placebo group [30.6 +/- 13.39 versus 41.64 +/- 18.34] [p<0.05]. The addition of dexamethasone 1mgld to standard long protocol decreased the number of itme used in patients over 35 years who hold known risk of low ovarian response

comparative study of GnRH antagonist and GnRH agonist in PCO patients undergoing IVF/ICSI cycles

Polycystic ovarian syndrome [PCOS] patients are prone to premature LH surge and ovarian hyperstimulation syndrome [OHSS]. Long GnRH analogue protocol and GnRH antagonist protocol are two methods utilized for induction ovulation in patients undergoing IVF/ICSI. The aim of this study was to compare the effects of GnRH agonists and antagonists in PCOS patients. A total of 60 PCOS patients under 35 years old were enrolled in this study. The patients have no history of thyroid disorder and hyperprolactinemia. All patients received OCP [LD] before starting the treatment. Then patients randomly divided into two groups. The agonist group underwent st and ard long GnRH analogue protocol. In antagonist group, HMG [150 IU/day] was started from third day of cycle. Then GnRH antagonist [0.25mg] was administered from 6th day after HMG initiation [LH /= 18mm, serum estradiol level on 6[th] day of HMG initiation and HCG injection time, fertilization and pregnancy rate between two groups. However there were significant differences regarding duration of treatment, duration of HMG usage, LH level at the initiation of HMG, OHSS rate and number of Metaphase II oocytes between two groups [p<0.05]. Usage of the GnRH antagonist may have more advantages such as the shorter duration of treatment and less gonadotrophin requirement. Furthermore, the incidence of OHSS can be reduced in GnRH antagonist comparing to agonist. For decreasing the risk of OHSS and abortion rate, we recommend long term use of OCP before starting the treatment

Experimental model of pulmonary allergic inflammation induced by latex in Balb/c

The prevalence of allergic airway diseases has dramatically increased in recent years all over the world. Murine models of allergic airway inflammation have provided helpful information about treatment and cellular and molecular mechanisms of the disease. Previous published works using murine models to investigate latex allergy did not introduce a complete characteristic eosinophilic allergic airway inflammation. Latex allergy is important due to serious health impacts and widespread use of its products. Thus, the aim of this study was to establish a new mouse model of latex allergic airway inflammation using aerosol inhalation. Initially, four groups of mice were injected intraperitoneally [IP] with 0, 10, 50, or 200 mg of latex extract and their serum anti-latex IgE titers were compared using ELISA to find out the optimum dose for IP injection. In the second stage, a standard protocol of inhalation was designed and three doses of latex extract solutions including 1%, 0.1%, and 0.01% were used to induce allergic airway inflammation. Characteristics of this model were shown by studying different parameters including bronchoalveolar lavage [BAL], cytokines [Interleukin-5 [IL-5] and interleukin-13 [IL-13]] and serum anti-latex IgE and IgG1 titers by ELISA, specific histologic changes in the lung and eosinophilia of the bone marrow, peripheral blood, BAL, and lung inflammatory foci. The aerosol inhalation of 1% latex allergens solution and pre-sensitization with 50 mg of latex in this study resulted in the development of characteristic allergic airway inflammation in BALB/c mice. These features included elevated allergen specific IgE and IgG1, peripheral blood, BAL and bone marrow eosinophilia and characteristic inflammatory response in lung with eosinophil infiltration. Elevated levels of IL-5 and IL-13 can be a sign of this type of inflammation. This paper describes a latex aerosol inhalational challenge model of eosinophilic airway inflammation in latex pre-sensitized BALB/c mice