Comparison of Two Different Ozone Injection Sites for Knee Osteoarthritis, Tibio-femoral Joint versus Supra-patellar Recess: An Open Randomized Clinical Trial

Background:The aim of this study was to compare the efficacy of ozone injection at Tibio-femoral joint with Supra-patellar recess on knee osteoarthritis (OA).Methods: In this randomized, controlled clinical trial, 99 patients with symptomatic knee OA were randomized into two groups. 47 patients selected to receive 7-8 ml ozone (20 μg/ml) through Tibio-femoral joint injection, and 49 patients received 10 ml ozone (20μg/ml) through supra-patellar recess injection by using in-plane ultrasound-guided. The primary outcome was the change from baseline in the visual analogue scale (VAS)(0-100 mm) pain score during 3 months after injection. Secondary outcome measures included the Western Ontario and McMaster universities OA Index (WOMAC), Lequesne index, time “Up and Go” (TUG) test, single-limb stance (SLS) tests, patient satisfaction, and adverse effects. All of these measurements were evaluated at the base time, 48 hours, 2 weeks, 1 month, 2 months, and 3 months after injection.Results:Both groups had significantly improvement in the primary and secondary outcome measures. VAS pain score except at the 3–month follow-up (16.8±13.3 versus 18.1±16.6, 95% CI, -7.33 to 4.73, p =0.6), WOMAC pain score, WOMAC stiffness score at all evaluated times, and WOMAC total score at 48 hours after injection (95% CI, -19.4 to -4.9) were significantly better among Tibio-femoral ozone injection compare to Supra-patellar recess injection (95% CI, -20.68 to -6.51,p<0.001)). In both groups satisfaction, TUG and SLS times were improved, but no significant difference was seen between groups (p>0.05). At the 3-month follow-up, WOMAC pain and total scores for only Tibio-femoral joint injection group as well as WOMAC function, TUG and SLS times for both groups were gradually coming back to the baseline.Conclusion:Ozone injection in both groups was associated withpain relief, functional improvement, and quality of life in patient with knee OA. Pain and stiffness of joint were improved better in Supra-patellar recess ozone injection

Effect of demographic and clinicopathologic factors on prognosis of early gastric cancer in Iran.

BACKGROUND: The aim of this study was to estimate some prognostic factors that affect on overall survival of patients with early gastric cancer. METHODS: A retrospective study had been done on patients diagnosed with early gastric cancer who registered in cancer registry center, Tehran, Iran, between December 21, 2001 and December 21, 2006 and all patients were followed by telephone contacts. The Kaplan-Meier method was performed to describe survival curves and log-rank test to compare the survival rate in subgroups. Cox regression was used to determine the prognosis factors. RESULTS: The mean age was 57.9 years and 72.6% of patients were male. Tumor size (>35 mm) and lymph node metastasis were established as significant factors for survival of patients with EGC in both univariate and multivariate analysis. CONCLUSION: The findings of this study indicate that lymph node metastasis and tumor size are the most independent prognostic factors in these patients.

Relation between demographic factors and type of gastrointestinal cancer using probit and logit regression.

BACKGROUND: Approximately 50,000 new cases of cancer occur each year in the Iranian population of 70.4 million. The organ system involved with more than 38% of all cancers is the gastrointestinal (GI) tract. The objective of this study was to investigate the relation between demographic factors and type of gastrointestinal cancer using probit and logit models. METHODS: This study was designed as a cross-sectional survey including all consecutive GI cancer patients admitted over a one year period in a randomly selected hospital group located in Tehran in 2006. RESULTS: The largest number of cases were colorectal cancers (40.0%), followed by gastric cancers (34.5%) and esophagus cancers (17.1%). There was a significant gender effect in the colorectal, gastric and esophagus cancer also there was a significant association between age and gastrointestinal cancers in both logit and probit regression. The factor of duration was not significant in gastric cancer. CONCLUSION: Men are more likely have colorectal cancer than women. Older people are more likely to have gastric cancer than younger people. For esophagus cancer all factors were significant. Results from probit and logit models were similar, indicating that probit analysis can be employed as a logit model to analyze relationships between demographic factors and cancer type.

Statistical comparison of survival models for analysis of cancer data.

BACKGROUND: The Cox Proportional Hazard model is the most popular technique to analysis the effects of covariates on survival time but under certain circumstances parametric models may offer advantages over Cox's model. In this study we use Cox regression and alternative parametric models such as: Weibull, Exponential and Lognormal models to evaluate prognostic factors affecting survival of patients with stomach cancer. Comparisons were made to find the best model. METHODS: To determine independent prognostic factors reducing survival time for stomach cancer, we compared parametric and semi-parametric methods applied to patients who registered in one cancer registry center located in southern Iran using the Akaike Information Criterion. RESULTS: Of a total of 442 patients, 266 (60.2%) died. The results of data analysis using Cox and parametric models were approximately similar. Patients with ages 60-75 and >75 years at diagnosis had an increased risk for death followed by those with poor differentiated grade and presence of distant metastasis (P<0.05). CONCLUSION: Although the Hazard Ratios in the Cox model and parametric ones are approximately similar, according to Akaike Information Criterion, the Weibull and Exponential models are the most favorable for survival analysis.

Quality of life in breast cancer patients--a quantile regression analysis.

BACKGROUND: Quality of life study has an important role in health care especially in chronic diseases, in clinical judgment and in medical resources supplying. Statistical tools like linear regression are widely used to assess the predictors of quality of life. But when the response is not normal the results are misleading. The aim of this study is to determine the predictors of quality of life in breast cancer patients, using quantile regression model and compare to linear regression. METHODS: A cross-sectional study conducted on 119 breast cancer patients that admitted and treated in chemotherapy ward of Namazi hospital in Shiraz. We used QLQ-C30 questionnaire to assessment quality of life in these patients. A quantile regression was employed to assess the assocciated factors and the results were compared to linear regression. All analysis carried out using SAS. RESULTS: The mean score for the global health status for breast cancer patients was 64.92+/-11.42. Linear regression showed that only grade of tumor, occupational status, menopausal status, financial difficulties and dyspnea were statistically significant. In spite of linear regression, financial difficulties were not significant in quantile regression analysis and dyspnea was only significant for first quartile. Also emotion functioning and duration of disease statistically predicted the QOL score in the third quartile. CONCLUSION: The results have demonstrated that using quantile regression leads to better interpretation and richer inference about predictors of the breast cancer patient quality of life.

Gastro-esophageal reflux symptoms and body mass index: no relation among the Iranian population.

An association between obesity and symptoms of gastro-esophageal reflux disease (GERD) has been frequently reported in western societies. A recent study indicated a consistent association between abdominal diameter and reflux-type symptoms in the white population, but no consistent association in the black population or Asians. It is unclear whether an association persists after adjusting for known risk factors of GERD among Asian populations. We did a population-based, cross-sectional interview study to estimate the strength of association between body mass and symptoms of reflux. During interviews, participants completed a valid gastro-esophageal reflux questionnaire. Odds ratio (OR) with 95% confidence interval (CI), calculated by logistic regression with multivariate adjustments for covariates, were the measures of association. Symptoms of reflux at least once a week over the past 3 months were reported by 522 (9.1%) of the 5733 interviewees. Among those who were overweight or obese (BMI> 25 kg/m2), the OR of having symptoms of reflux was 0.88 (95% CI: 0.66-1.16) compared with those who were not overweight or obese. Thus, among Asians, symptoms of GERD occur independently of body mass index.

Association between risk of breast cancer and fertility factors--a latent variable approach.

BACKGROUND: Breast cancer is the most common malignant tumor in females. Many studies have been carried out in order to assess the reproductive risk factors. Particular attention has focused on information regarding fertility, including breastfeeding, age at first birth and number of live births. These factors are highly correlated with each other. The objective of this study was to employ latent variables to reduce the confounding effect of this correlation with a logistic regression analysis. METHODS: The investigation drew upon results from a dataset belonged to a hospital based case-control study covering 303 breast cancer patients and 303 hospital controls. Data were collected through interview and reproductive variables included age at first full-term pregnancy and live birth, number of pregnancies and live births, and total length of breast feeding. Latent variables were generated using factor analysis and principal components analysis. RESULTS: The study revealed that for both latent variable approaches the odds ratios of two latent variables significantly indicated a protective impact of number of pregnancy and live birth and breastfeeding and a prognostic relation with age at first pregnancy or live birth. CONCLUSION: The findings suggest that breastfeeding and decreasing age at first live birth have protective influences on breast cancer risk. Also using statistical model with latent variables in the presence of collinear data leads to reliable results.

Socioeconomic factors association with knowledge and practice of breast self-examination among Iranian women.

BACKGROUND: Breast cancer is the leading type of cancer in women and is one of the most frequent cancers among Iranian women. Delay in diagnosis and treatment of breast cancer diminishes a women's chance of survival. Breast self- examination (BSE) may be effective in early detection. The purpose of this study was to identify the relationship between Iranian women's socioeconomic status and their knowledge and practice of BSE. METHODS: Data were from a hospital-based case-control study among women diagnosed with breast cancer. Control subjects were matched to patients on age. 303 breast cancer patients and 303 control women were interviewed. Socioeconomic status and information including knowledge and practices of breast self examination and clinical breast examination were recorded and compared. RESULTS: The mean +/- SD age of cases and controls was 48.2 +/- 9.8 and 50.2 +/- 11.1 (range 24-84 years), respectively. The study revealed that there were significant relationships between education level and knowledge and practices of breast self examination in both cases and controls, increase in usage being observed with the level of education (P<0.05). CONCLUSION: The findings suggest that the knowledge and practices of women toward breast cancer early detection are inadequate in women with a lower level of education. Mass media cancer education should promote widespread access to information about early detection behavior.

Comparing Cox regression and parametric models for survival of patients with gastric carcinoma.

BACKGROUND: Researchers in medical sciences often tend to prefer Cox semi-parametric instead of parametric models for survival analysis because of fewer assumptions but under certain circumstances, parametric models give more precise estimates. The objective of this study was to compare two survival regression methods - Cox regression and parametric models - in patients with gastric adenocarcinomas who registered at Taleghani hospital, Tehran. METHODS: We retrospectively studied 746 cases from February 2003 through January 2007. Gender, age at diagnosis, family history of cancer, tumor size and pathologic distant of metastasis were selected as potential prognostic factors and entered into the parametric and semi parametric models. Weibull, exponential and lognormal regression were performed as parametric models with the Akaike Information Criterion (AIC) and standardized of parameter estimates to compare the efficiency of models. RESULTS: The survival results from both Cox and Parametric models showed that patients who were older than 45 years at diagnosis had an increased risk for death, followed by greater tumor size and presence of pathologic distant metastasis. CONCLUSION: In multivariate analysis Cox and Exponential are similar. Although it seems that there may not be a single model that is substantially better than others, in univariate analysis the data strongly supported the log normal regression among parametric models and it can be lead to more precise results as an alternative to Cox.