Ghodratollah Roshanaei, Azam Komijani, Abdolazim Sadighi Pashaki, Javad Fardmal,
Volume 16, Issue 11 (2-2014)
Abstract
Background: It can be used different models such as nonparametric, semi-parametric and parametric to estimation of survival. Depending on the nature of the data, some methods may be more appropriate. Using of appropriate model result more accuracy estimation of survival and it's affected. so the aim of this study estimation of survival and determination of its related risk factor. Materials and Methods: In this study, 169 patients with colorectal cancer who had treated in Hamadan MRI Center from March 2005 to Jun 2013 were evaluated. Survival time of patients is considered from diagnosis time to death or end of study. The effect of Demographic and clinical risk factors on survival is assessed by parametric model. follow up of patient Data were analyzed using Spss16 and R statistical software.
Results: The median survival was 4.3±40 months. Univariate analysis showed that the effect of staging of tumor, tumor grade, histology type of tumor, metastasis and relapse on survival were significant but in multivariate model histology type of tumor and metastasis were significant.
Conclusion: using of appropriate statistical model for detection of affected risk factor on patient with colorectal cancer can be prevented progression of disease and increased of survival of them.
Nasim Karimi, Maliheh Safari, Ghodratollah Roshanaei, Jalal Poorolajal,
Volume 21, Issue 6 (12-2018)
Abstract
Background and Aim: Acquired immunodeficiency syndrome is caused by body contamination with human immunodeficiency virus. Several factors affect the survival of people with AIDS, which are often examined using Cox regression models. The default is to use the Cox model as a proportionate hazard, which in case of a violation, this model does not have the required performance. Therefore, the aim of this study was to determine the effective factors on survival of AIDS patients using the developed Cox model.
Materials and Methods: In this cohort study, 1050 patients with AIDS who referred to Imam Khomeini and Zamzam Behavioral Counseling Centers in Tehran Province during the years 2004 to 2014 were studied. The effect of clinical and demographic factors on survival of patients has been investigated using extended Cox model.
Findings: 79% of patients were men. The mean age of the patients was 34.84 ± 10. 21 years old. The mean of the diagnosis time to AIDS was 23.64 ± 15.53 months. 76% of patients were cencored. Age at diagnosis, transmission modes, ART, CD4 count, and time to diagnosis of AIDS in univariate and multivariate analysis were significant
(p <0.05).
Conclusion: Several clinical factors have implications for the survival of AIDS patients. The most important of these factors is the use of ART and early detection of the disease, which greatly increases the chance of survival of the affected population. Therefore, it seems necessary to provide screening and treatment services for high-risk individuals.
Rasoul Najafi, Fatemeh Amiri, Ghodratoalleh Roshanaei, Mohammad Abbasi,
Volume 22, Issue 2 (6-2019)
Abstract
Background and Aim: Colon cancer is one of the most common cancers in the gastrointestinal tract. Colon cancer is the third death cause among cancers. The aim of this study was to estimate the survival rate and determine the effective factors in colon cancer patients.
Materials and Methods: In this study, 193 colon cancer patients referring to Hamadan Imam Khomeini Clinic during the years 2003-2017 in a retrospective cohort study were used. Follow up of all patients was done by referral and phone call up to 2017. The Kaplan -Meyer model was used to estimate the survival of patients. Also, the effect of prognostic factors on the survival of patients was obtained by Cox regression model. The software used to analyze the data was STATA 11 and the significance level was 0.05.
Ethical Considerations: This study with research ethics code IR.UMSHA.REC.1396.144 was approved in Research Ethics Committee of Hamadan University of medical sciences, Iran.
Findings: The mean age of the patients at diagnosis was 57.09 ± 12.9 years. The probability of survival of one-, three- and five-year was 0.82, 0.61 and 0.48 percent, respectively. Also, the cancer stage has a significant effect on survival time of the patients.
Conclusion: Based on the Cox model, only the stage of cancer was effective on the survival time of patients with colon cancer. Therefore, timely diagnosis also helps prevent disease progression, as well as increase the survival time of the patient, especially at an advanced age.
Fatemeh Amiri, Ghodrat Roshanaei, Meysam Olfati Far, Rasoul Najafi, Jalal Poorolajal,
Volume 24, Issue 2 (June & July 2021)
Abstract
Background and Aim: Acquired Immunodeficiency Syndrome (AIDS) caused by Human Immunodeficiency Virus (HIV), is a chronic and potentially life-threatening disease. Numerous factors affect its development and progression. Therefore, the present study attempted to identify characteristics impacting the prognosis and progression of AIDS using multistate models.
Methods & Materials: The present retrospective study consisted of 2185 patients affected with HIV referring to Behavioral Disease Counseling Centers in Tehran City, Iran, from 2004 to 2013. We considered multiple states of AIDS, tuberculosis, and tuberculosis/AIDS in the natural history of the disease (from the onset of HIV disease until death occurred). Then, we applied the multistate models, to examine the effect of contextual demographic and clinical variables on survival time; subsequently, the transition probabilities of HIV.
Ethical Considerations: This study was approved by the Research Ethics Committee of Hamadan University of Medical Sciences (Code: IR.UMSHA.REC.1396.117).
Results: HIV-Related deaths in individuals with an incarnation history were 2.40 times higher than in those without the prison history. Death risk was also 1.70 and 1.80 times higher in those aged 25-44 and 44 years, respectively, compared to the individuals aged less than 25 years. An inverse relationship was also found between CD4 levels and the risk of death in our participants.
Conclusion: Antiretroviral therapy, CD4 count, age, and history of imprisonment were the main factors in the progression of the disease and subsequent death in HIV patients. Thus, preventing the further spread of the disease to the community and controlling the disease in the patients requires targeted educational and therapeutic interventions; accordingly, the community will be familiarized with transmission routes and the preventing principle of disease. Furthermore, we can encourage patients to visit the healthcare centers early.