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1.  The Association Between Obstructive Sleep Apnea and Depression in Older Adults 
Nursing and Midwifery Studies  2016;5(2):e32585.
Depression is the most frequent psychiatric disorder among the elderly. Obstructive sleep apnea (OSA) is a chronic and prevalent disease that has an ambiguous role in triggering depression. Several researches with contradictory findings have been performed about the association between OSA and depression.
This study aimed to investigate the association between OSA and depression among elderly.
Patients and Methods
A total of 350 home residing elderly took part in this case-control study. The participants were selected using clustering method. All cases were divided into two groups of depressed and non-depressed using the geriatric depression scale (GDS). Then they were matched in age, gender, education and body mass index (BMI). Berlin questionnaire (BQ) was used to diagnose OSA. Data analysis was performed using Mann-Whitney U test, t-test, Chi-square and Fisher’s exact tests and odds ratio.
Totally, 60.6 % of depressed group and 18.9 % of non-depressed group were in high risk for OSA. A significant association was found between OSA and depression (P < 0.001, OR = 6.61, CI 95 % = 4.1 - 10.7). In addition, a significant association was found between gender and OSA (P = 0.008).
OSA was associated with depression among the elderly patients. Given the high prevalence of OSA in older adults, implementation of screening methods is necessary to identify people at high risk of OSA.
PMCID: PMC5002089  PMID: 27579333
Obstructive Sleep Apnea; Depression; Elderly
2.  Malignant Mesothelioma Versus Metastatic Carcinoma of the Pleura: A CT Challenge 
Iranian Journal of Radiology  2016;13(1):e10949.
Malignant pleural mesothelioma (MPM) is a rare malignant neoplasm of the pleura that typically affects individuals occupationally exposed to asbestos through a variety of industries. MPM presents with several CT features similar to more common pleural diseases such as metastatic pleural malignancy.
The aim of this study is to differentiate malignant pleural mesothelioma from metastatic carcinoma of the pleura by pathological and radiological assessment in order to investigate accuracy of CT scan in this regard and to compare CT features of these two malignancies.
Patients and Methods:
Chest CT scans of 55 pleural malignancy patients including MPM and metastatic pleural malignancy were evaluated in this retrospective study. The pathologist made the definite diagnosis based on immunohistochemistry. A chest radiologist unaware of the pathology diagnosis observed all CT scans. Several parameters including pleural thickening, pleural effusion, thickening of inter lobar fissure, contralateral extension, contraction of involved hemithorax, parenchymal involvement (infiltration, nodules, fibrosis), pleural mediastinal involvement, lymphadenopathy, extrapleural invasion (hepatic, chest wall, diaphragm, intraperitoneal), and pericardial involvement were checked. Data analysis was carried out using SPSS version 16, and the ability of CT scan to differentiate malignant pleural mesothelioma and metastatic pleural diseases was investigated.
Totally 29 males and 26 females were assessed in this study. Based on pathology, 17 MPM and 38 metastatic pleural malignancies were diagnosed. According to CT study, about 82% of the patients with MPM and about 79% of the patients with metastatic pleural diseases were correctly diagnosed by a radiologist. The most common findings suggestive of MPM were pleural thickening (88.2%), loculated effusion (58.8%), and thickening of the interlobar fissure (47.1%). Whereas free pleural effusion (71.7%), parenchymal infiltration (65.8%) and pleural thickening (63.2%) were most prevalent parameters among metastatic cases.
CT scan is highly accurate in differentiating malignant pleural mesothelioma and metastatic pleural diseases. Pleural thickening and thickening of interlobar fissure lead us to the diagnosis of MPM and massive free pleural effusion is more commonly seen in metastatic pleural malignancy.
PMCID: PMC4837229  PMID: 27110327
Pleural Diseases; Malignant Mesothelioma; Tomography; X-Ray Computed; Neoplasm Metastasis
3.  Incidence Trends and Geographical Distribution of Nasopharyngeal Carcinoma in Iran 
Nasopharyngeal carcinoma (NPC) has known as a highly distinct kind of head and neck cancer. This distinction has been due to its clinical presentation, epidemiology, outcome, and treatment. There have not been any reports of epidemiological analysis of NPC in Iran. This study has evaluated the incidence rates and trends of nasopharyngeal carcinoma in the Iranian population during 2004 to 2009.
The data have collected from the Iranian national cancer data system registry. All the cases of nasopharyngeal carcinoma (with the topography code 11 and histology of carcinoma) have retrieved and analyzed from an overall cancer database during a 6-year period. The data have analyzed by using the SPSS, version 16.
To determine the current incidence of NPC in Iran, we have examined the NPC cases from 2004 to 2009. A total of 1431 cases (981 male and 450 female NPC patients) have analyzed epidemiologically in this study. The mean age of the patients was 47.1 years. The incidence was 0.33 per 100000 persons. The overall incidence rate have increased annually (p<0.05). The incidence of NPC gradually increased with age. Prefectures that bordering the Caspian Sea have proved to have a higher incidence than the other studied areas.
Our study has indicated an increasing trend in the incidence of nasopharyngeal carcinoma. Therefore; attempts should be precipitated for prevention.
PMCID: PMC4571825  PMID: 26396710
Incidence; Nasopharyngeal carcinoma; NPC; Trend
4.  Recent Trends and Geographical Distribution of Thyroid Cancer in Iran from 2004 to 2009 
To prevent and control the cancers in Iran, the Iranian Department of Health has released the cancer rates data of the country. As the report has suggested, the incidence rate of thyroid cancer would be the most rapidly increasing among all the cancers. The study has aimed to carry out a qualitative assessment of thyroid cancer in Iran, during the 2004 to 2009, in a cross-sectional setting.
The incidence rates, the trend of individual provinces, the mean age at which the disease occurred, the correlation between incidence rate and median urinary iodine concentration were the parameters evaluated in our study.
The average annual incidence rate during these six years was 2.17 per 100000. Chaharmahal-o-bakhtiari, had the highest incidence rate, but the East Azerbaijan provinces had the lowest incidence rates respectively. The age of diagnosis was the lowest in Ardebil but the highest in West Azerbaijan. In our study, we have found the positive correlation between thyroid cancer incidences with low urinary iodine concentration among all provinces (p-value=0.025).
Presently, the only recognized measure procedure for reducing thyroid cancer risk would be perhaps the correction of median urinary iodine concentration. Further researches have seemed to be required for investigation the other factors, in order to introduce preventive measures in Iran.
PMCID: PMC4571982  PMID: 26396709
Thyroid cancer (TC); Incidence rate; Cancer registry; Urinary iodine concentration; Iran
5.  Clinicopathologic and Survival Characteristics of Malignant Pleural Mesothelioma Registered in Hospital Cancer Registry 
Tanaffos  2014;13(2):6-12.
Malignant pleural mesothelioma (MPM) is a rare but fatal thoracic tumor, which in the majority of patients is caused by prolonged exposure to asbestos fibers. We aimed at presenting clinicopathological and treatment outcomes of 60 patients of MPM registered in our hospital cancer registry.
Materials and Methods
Demographic characteristics of patients, exposure to asbestos, smoking habit, their clinicopathologic characteristics and survival analysis were described.
Sixty patients had MPM. Forty patients (66.7%) were men. The mean age of patients was 55.8±11 years. Chest pain and dyspnea were the most prevalent symptoms (31.7%, and 30%, respectively). Thirty-six (61.7%) patients reported asbestos exposure. The median survival and Progression free survival (PFS) were 10.5 months (0.95CI=9.22-11.78) and 7.57 months (0.95CI=5.68-9.45), respectively. In multivariate analysis, exposure to asbestos and epithelioid subtype significantly extended the survival time. Bilateral involvement, high blood level of LDH and platelet count ≥400,000 significantly shortened the overall survival.
MPM is still an important health problem in Iran. Given the aforementioned results, developing a national program to eliminate asbestos-related diseases according to the world health organization (WHO) recommendation is necessary.
PMCID: PMC4260067  PMID: 25506370
Cancer registry; Malignant pleural mesothelioma; Survival
6.  Development, Validity and Reliability of Sexual Health Measures for Spinal Cord Injured Patients in Iran 
This study developed and validated a questionnaire to measure the sexual health of patients with spinal cord injuries (SCI).
Materials and Methods:
This was a cross-sectional study conducted at the Brain and Spinal Injury Research Center (BASIR), Tehran, Iran. Extensive review of literature, expert opinions, and encounters with SCI patients were used to develop and validate the questionnaires. There were 40 (32 males, 8 females) patients with SCI that presented for treatment at BASIR who enrolled in the study. Participants completed the questionnaires while they were admitted for medical care and during treatment follow-up visits. Participants completed the questionnaires twice, at a 2-4 week interval. Reliability testing for each measure was performed separately. Cronbach’s alpha was used for internal consistency and test-retest was used for reliability.
An expert committee approved the face and content validities of the questionnaires, Internal consistency of our questionnaires, was acceptable according to Cronbach’s alpha that ranged from 0.73 for the sexual activity measure to 0.90 for the sexual adjustment measure. Test-retest reliability was satisfactory. Intraclass Correlation Coefficient (ICC) of measures ranged from 0.65 for sexual function to 0.84 for sexual activity.
The sexual health measures has provided a valid assessment of sexualityrelated matters in this sample of patients with SCI, which suggests that evaluation of sexual well-being may be useful in clinical trials and practice settings. Overall, the sexual health measures shows good internal consistency and test-retest reliability.
PMCID: PMC3850335  PMID: 24520468
Spinal Cord Injury; Sexual Health; Validity; Reliability
7.  Epidemiology of multiple sclerosis in Qom: Demographic study in Iran 
Iranian Journal of Neurology  2013;12(4):136-143.
Recent studies have demonstrated controversial results and somewhat increased frequency of multiple sclerosis (MS). We reevaluated the files of MS patients from Qom Province of Iran in order to investigate the epidemiology of the disease.
Demographic and clinical records of 592 MS patients were reviewed, which included; age, sex, date of birth, marital and occupation status, presenting symptoms, time of onset, type and family history of MS, and history of autoimmune or other diseases.
At the time of our study, 11 patients had died, and 581 were alive with a total female-to-male ratio of 3.4. The mean age of onset of the disease was 34.25 ± 9.01 for all the patients. 11.2% of patients had positive family history of MS. The majority of patients (80.1%) showed relapsing-remitting (RR) pattern. The prevalence of MS was calculated as 50.4/100000 for Qom.
Qom is located within a high risk zone of MS. Although we found evidences about the role of environmental factors, geographical distribution, and etcetera, many more studies need to be performed in this respect.
PMCID: PMC3829303  PMID: 24250923
Demography; Epidemiology; Iran; Multiple Sclerosis; Prevalence
8.  Specific count model for investing the related factors of cost of GERD and functional dyspepsia 
The purpose of this study is to analyze the cost of GERD and functional dyspepsia for investing its related factors.
Gastro-oesophageal reflux disease GERD and dyspepsia are the most common symptoms of gastrointestinal disorders. Recent studies showed high prevalence and variety of clinical presentation of these two symptoms imposed enormous economic burden to the society.
Cost data that related to economics burden have specific characteristics. So this kind of data needs to specific models. Poisson regression (PR) and negative binomial regression (NB) are the models that were used for analyzing cost data in this paper.
Patients and methods
This study designed as a cross-sectional household survey from May 2006 to December 2007 on a random sample of individual in the Tehran province, Iran to find the prevalence of gastrointestinal symptoms and disorders and its related factors. The Cost in each item was counted. PR and NB were carried out to the data respectively. Likelihood ratio test was performed for comparison between models. Also Log likelihood, Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC) were used to compare performance of the models.
According to Likelihood ratio test and all three criterions that we used to compare performance of the models, NB was the best model for analyzing this cost data. Sex, age and insurance statues were being significant.
PR and NB models were carried out for this data and according the results improved fit of the NB model over PR, it clearly indicates that over-dispersion is involved due to unobserved heterogeneity and/or clustering. NB model in cost data more appropriate fit than PR.
PMCID: PMC4017531  PMID: 24834282
GERD; Dyspepsia; Cost; Count models; Zero inflated models
9.  Random effect model for identifying related factors to virological response in HCV patients 
This study aims to employ random effect model to evaluate prognostic factors of hepatitis C.
In recent years, Hepatitis C virus (HCV) infection has been a major cause of liver diseases worldwide and represents a major public health problem. Evaluation of risk factors and a community intervention in order to decrease the problem is one of the solutions which help protect people from the infection.
Patients and methods
The data was collected from a longitudinal study during 2005-2010. The response variable in this study was the viral load of each HCV patient during the treatment, immediately after the treatment and 3 to 4 months after the end of the treatment. The outcome variable of interest is the viral load of HCV patients. For analyzing repeated measure viral load of HCV patients, random effect models were used.
The results obtained from random effect model showed that treatment protocol and time statistically significant. The variance component was statistically differing with zero.
According to the results time had a positive effect on rate of viral load of patient. Combination therapy of Peg-interferon plus Ribavirin increased the rate of virological response.
PMCID: PMC4017535  PMID: 24834290
HCV; Viral load; Random effect; Longitudinal data

Results 1-9 (9)