Incidence of side effects of antituberculosis drugs and their related factors in northern Iran: a retrospective cohort study.

Background: Antituberculosis drugs may cause mild, moderate or severe adverse drug reactions (ADR) leading to poor compliance. Description of the pattern of ADR and their related factors can help tuberculosis (TB) control program as part of the WHO programs. This study aims to investigate the incidence of ADR and associated factors among TB patients in northern Iran. Methods: This is a retrospective cohort study. The required information, including year of diagnosis, age, gender, residence area, nationality, HIV co-morbidity, history of anti TB treatment and ADR, was obtained from the Deputy of Health, Mazandaran University of Medical Sciences, Iran. All data were analyzed using SPSS version 21 software. Results: Out of 3903 TB patients, 136 (3.5%) experienced major ADR. The incidence of ADR for men and women as well as for those with and without previous treatment history were 3.9% vs. 3.3% and 5.3% vs. 3.4%, respectively (p>0.05). Multiple logistic regression models showed a higher chance of ADR among those aged over 59 compared with those aged under 29 (OR=2.63, 95% confidence interval: 1.54-4.49). Conclusions: Age over 59 can be considered a risk factor for ADR with anti-TB drug administration.

Relationship between smoking and tuberculosis recurrence: A systematic review and meta-analysis.

INTRODUCTION: Of the problems in tuberculosis (TB) control program is the recurrence of this disease. In some studies, smoking has been reported as the most important risk factor. Therefore, the present study aimed at examining the association between smoking and tuberculosis recurrence using meta-analysis. METHODS: To report the findings of this meta-analysis, we used PRISMA. The protocol of this study has been recorded in PROSPERO. The research question has been formulated based on PICO, and the search was performed using both MeSH and non-MeSH keywords. After screening and selecting the articles and evaluating their quality using the NOS checklist, the overall estimate of the odds ratio of tuberculosis recurrence in smokers was assessed with a 95% confidence interval. RESULTS: Fourteen studies met the inclusion criteria. The total number of samples in the group of patients with tuberculosis recurrence was 1988 with 855 (43%) smokers, and in the group of patients affected by tuberculosis without recurrence, it was 27,226 with 7503 (27.56%) smokers. In 13 studies, the odds ratio of tuberculosis recurrence was higher in smokers; this difference was statistically significant in 12 of them. Combining the results of these 14 studies, the odds ratio of tuberculosis recurrence in smokers was 2.10 times higher, using the random effects model (95% CI:1.69, 2.61). CONCLUSION: Based on the results of study present, smoking increases the risk of tuberculosis recurrence. Therefore, to eradicate tuberculosis by 2030, more serious interventions should be taken to quit smoking, which in turn reduces the incidence of tuberculosis.

The impact of diabetics and smoking on gender differences of smear positive pulmonary tuberculosis incidence.

BACKGROUND: Several determinants are responsible for different incidences of smear positive pulmonary tuberculosis (TB). The main determinants are cigarette smoking and diabetes mellitus. The aim of this study is to determine the effect of these risk factors effect modifiers in TB/gender association. METHODOLOGY: In this retrospective cohort, relative risk of gender in developing smear positive TB as well as its interaction with smoking and diabetes mellitus were investigated. RESULTS: Of 1243 smear positive TB cases, 63.2% were male. Prevalences of diabetes mellitus among men and women TB cases were 9.2% and 22.9% respectively (p<0.001). Frequency of cigarette smoking among men was significantly higher than that in women (61.7% vs. 7.6% respectively, p<0.001). Male gender, increased the risk of developing smear positive TB as of 98% and 5% in smokers and non-smokers respectively (p=0.001), indicating an interaction between gender and smoking in the effect on TB. In addition, male gender increased the risk of TB as of 13% and 34% in patients with and without diabetes mellitus respectively (p=0.300) indicating no interaction between gender and diabetes mellitus on TB incidence. CONCLUSION: Our study showed that cigarette smoking is a determinant factor for gender differences in TB incidence but diabetes mellitus does not affect the association between TB and gender.

Determinant factors for mortality during treatment among tuberculosis patients: Cox proportional hazards model.

BACKGROUND: Investigating the survival of tuberculosis (TB) patients is one of the main parts of the TB control program. It can be related to many factors. This study aimed to estimate the survival experience and its associated factors among these patients. METHODOLOGY: All TB patients detected during March 2005 to 31 September 2014 were entered into this prospective cohort. Each patient was investigated from the diagnosis date and followed until the last available information during treatment. Data analysis was performed using Kaplan Meier and multivariate Cox regression models. RESULTS: The survival experience of 2493 TB patients was investigated 73.7% of which were pulmonary type. Mean and median survival time were 6.5 and 6.2 months respectively. The incidence rate of death among patients during the treatment courses was 0.99 (95% confidence interval: 0.84-1.1) per 100 person-months. Controlling the confounders, the incidence (95% confidence interval) of death was significantly higher among men (HR=1.8; 1.2-2.6), diabetic patients (HR=1.7; 1.2-2.6), cancerous patients (HR=4.8; 2.6-8.8) and HIV positive patients (HR=22.1; 7.3-66.4). CONCLUSION: This study showed that male gender, TB/HIV co-infection and concurrent development of TB and cancer were determinant factors of death during the treatment period of TB.

Estimating the Survival of Patients With Lung Cancer: What Is the Best Statistical Model?

OBJECTIVES: Investigating the survival of patients with cancer is vitally necessary for controlling the disease and for assessing treatment methods. This study aimed to compare various statistical models of survival and to determine the survival rate and its related factors among patients suffering from lung cancer. METHODS: In this retrospective cohort, the cumulative survival rate, median survival time, and factors associated with the survival of lung cancer patients were estimated using Cox, Weibull, exponential, and Gompertz regression models. Kaplan-Meier tables and the log-rank test were also used to analyze the survival of patients in different subgroups. RESULTS: Of 102 patients with lung cancer, 74.5% were male. During the follow-up period, 80.4% died. The incidence rate of death among patients was estimated as 3.9 (95% confidence [CI], 3.1 to 4.8) per 100 person-months. The 5-year survival rate for all patients, males, females, patients with non-small cell lung carcinoma (NSCLC), and patients with small cell lung carcinoma (SCLC) was 17%, 13%, 29%, 21%, and 0%, respectively. The median survival time for all patients, males, females, those with NSCLC, and those with SCLC was 12.7 months, 12.0 months, 16.0 months, 16.0 months, and 6.0 months, respectively. Multivariate analyses indicated that the hazard ratios (95% CIs) for male sex, age, and SCLC were 0.56 (0.33 to 0.93), 1.03 (1.01 to 1.05), and 2.91 (1.71 to 4.95), respectively. CONCLUSIONS: Our results showed that the exponential model was the most precise. This model identified age, sex, and type of cancer as factors that predicted survival in patients with lung cancer.

Estimating Tuberculin Skin Test Reactions among Children and Teenagers Who Received the Bacillus Calmette-Guerin Vaccination at Birth: A Meta-analysis.

OBJECTIVES: Tuberculin skin reaction size is one indicator of bacillus Calmette-Guérin (BCG) vaccine efficacy and a way to diagnose latent infection. Several primary studies have examined this issue. Combining the results of these studies using a meta-analysis will provide reliable evidence regarding this indicator for policymakers. This study aimed to estimate the total frequency of different tuberculin skin test reactions among Iranian children and teenagers who received the BCG vaccination at birth. METHODS: National and international databanks were searched using relevant keywords. After the search strategy was restricted and duplicates were excluded, the titles and abstracts of the remaining papers were screened. All included studies included healthy children who received the BCG vaccine without confirmed tuberculosis exposure. Heterogeneity of the results was assessed using the Cochrane test and I2 index showed the random effects model as the best model for estimating the pooled results. RESULTS: We combined the results of 14 primary studies including purified protein derivative reaction test measures of 26,281 Iranian children. The frequencies (95% confidence intervals) of the reactions were 8.5% (6.2-10.8) for patients with a reaction size ≥ 10 mm, 29.9% (22.3-37.4) for a reaction size of 5-9 mm, and 60% (48.9-71.1) for a reaction size < 5 mm. CONCLUSION: Our study showed that large numbers of Iranian children and teens have no positive BCG vaccine reaction and a considerable number of children have been exposed to Mycobacterium tuberculosis.

Decline in lung function among cement production workers: a meta-analysis.

BACKGROUND: Several studies with different results have been performed regarding cement dust exposure and its pathogenic outcomes during the previous years. This study aims to combine these results to obtain a reliable estimate of the effect of exposure to cement dust. METHODS: PubMed and other data banks were searched to identify required electronic articles. The search was extended interviewing with relevant experts and research centers. Point and pooled estimates of outcome with 95% confidence intervals were estimated. RESULTS: Participants were 5371 exposed and 2650 unexposed persons. Total mean differences (95% confidence intervals) were estimated as of -0.48 (-0.71 to -0.25) L for forced vital capacity (FVC), -0.7 (-0.92 to -0.47) L for forced expiratory volume in the first second (FEV1), -0.43 (-0.68 to -0.19) L for FEV1/FVC%, -0.73 (-1.15 to -0.30) L/min for PEFR and -0.36 (-0.51 to -0.21) L/s for FEF25-75. CONCLUSION: Our meta-analysis showed that cement dust has significant impact on lung function and reduces the indicators of FVC, FEV1, FEV1/FVC, PEFR and FEF25-75.

Estimating the prevalence of Positive Tuberculin Skin Test Reactions in General Population and High-risk Groups: A Meta-analysis.

Results of tuberculin skin test (TST) surveys among different populations have been reported in many studies as a method for detecting primary Mycobacterium tuberculosis infection. Combining these results provides reliable estimates of primary latent tuberculosis (TB) infection for health policymakers. This study aims to estimate the prevalence of latent TB infection in general and high-risk populations in Iran. National and international databanks were searched using specific keywords. After restricting the search strategy, duplicates exclusion, reviewing titles, abstracts and full texts, and quality assessment, eligible papers were selected. The heterogeneity between the results was assessed according to Cochrane and I-squared indices. The prevalence of positive TST reactions was estimated using fixed and random effect models. Totally, 33 papers were entered into the meta-analysis reporting the TST results in 12693 people aged over 18. The prevalence (95% confidence intervals) of positive TST reactions in all groups, general population, health staff, medical students, household close contacts, patients with TB, immunocompromised patients, HIV/AIDS patients, and those with risky behaviors was 26.2% (19.6-32.8), 25.4% (4.8-46.1), 38.9% (27.4-50.9), 13.4% (9.9-16.7), 35.9% (16.4-55.5), 13.7% (8.4-18.9), 29.4% (21.2-37.7), and 14.6% (3.9-25.3), respectively. Our study showed great varieties of positive TST results among different Iranian subpopulations. Furthermore, the prevalence of latent TB infection among health professionals and family members of TB patients was considerably different from that of the other subgroup. Since TB control programs such as active case finding are routinely conducted among household close contacts and HIV/AIDS cases, other high-risk groups including health-care workers and immunocompromised patients should be taken into consideration in these preventive programs.