Can the salivary urea and stimulated saliva concentration be a marker of periodontal diseases in opioid users? A case-control study.

Introduction: & Aim: Microbial plaque is the primary cause of periodontal diseases, and smoking and opioid addiction can accelerate microbial plaque formation and disease progression. Adequate saliva flow and salivary urea concentration are important parameters for a healthy periodontium. In this study, the relationship between Periodontal Diseases and the History of opioid addiction was investigated by measuring the Salivary Urea and Stimulated Saliva Concentration. Materials & methods: This case-control study was conducted on 240 patients (120 cases and 120 controls) in 2021 referred to addiction treatment centers and the dental clinic in Iran, Birjand. The control and case groups were matched in terms of age. Demographic, base data, and clinical examination results were collected by a checklist. Data were analyzed using SPSS 19 and one-way ANOVA and chi-square tests. P-value <0.05 was considered as the significance level. Results: Periodontitis severity was significantly higher in the case group than in the control group (P-value = 0/000). Salivary urea concentration significantly increased in both case and control groups with an increase in periodontitis severity (P-value = 0/003 in the case group and P-value = 0/000 in the control group), but there was no significant relationship between the stimulated saliva flow rate and the severity of periodontitis in these two groups (P-value>0.05). Conclusion: Following the use of opioids, the flow of saliva decreases, and with the exacerbation of the periodontal disease, the concentration of urea in saliva increases. Therefore, it seems that the analysis of saliva parameters, including urea concentration, can be useful for the diagnosis of periodontal disease, and saliva urea concentration is not directly related to opioid use.

Performance of two educational approaches in increasing knowledge of high-school students about COVID-19 during the first wave of pandemic.

OBJECTIVES: The coronavirus disease (COVID-19) pandemic has greatly altered peoples' daily lives. Teachers and students were found quite unprepared for the emergence of the first COVID-19 wave. So, improving the knowledge of students about COVID-19 is an important issue. METHODS: In this study, 240 high students attended. Two interventions with the same contents, but in different ways, were delivered. A structured questionnaire was utilized to collect data on demographic information, and information about the behavioral intention toward COVID-19 before and after the educational interventions as well as a control group that received no educational intervention. RESULTS: students in all arms had similar baseline knowledge of COVID-19. The results of the post-analysis showed the efficiency of educational techniques in increasing students' knowledge about COVID-19. So the audio-visual training method performed significantly better than the visual training method (p = 0.03). Both approaches achieved better scores than the control group (P < 0.001). CONCLUSION: During the outbreak of COVID-19, multimedia-based learning is a more effective educational approach and can improve the learning outcomes related to COVID-19 and achieve learning goals without close contact than written materials.

Survival Evaluation of Hospitalized COVID-19 Patients with Cox Frailty Approach.

INTRODUCTION: The survival cox analysis is becoming more popular in time-to-event data analysis. When there are unobserved /unmeasured individual factors, then the results of this model may not be dependable. Hence, this study aimed to determine the factors associated with Covid-19 patients' survival time with considering frailty factor. METHODS: This study was conducted at 1 of the hospitals in Iran, so that hospitalized patients with COVID-19 were included. Epidemiological, clinical, laboratory, and outcome data on admission were extracted from electronic medical records. Gamma-frailty Cox model was used to identify the effects of the risk factors. RESULTS: A total of 360 patients with COVID-19 enrolled in the study. The median age was 74 years (IQR 61 - 83), 903 (57·7%) were men, and 661 (42·3%) were women; the mortality rate was 17%. The Cox frailty model showed that there is at least a latent factor in the model (P = 0.005). Age and platelet count were negatively associated with the length of stay, while red blood cell count was positively associated with the length of stay of patients. CONCLUSION: The Cox frailty model indicates that in addition to age, the frailty factor is a useful predictor of survival in Covid-19 patients.

Dentistry during COVID-19: patients' knowledge and satisfaction toward health protocols COVID-19 during dental treatment.

BACKGROUND: Coronavirus disease 2019 (COVID-19) as an infectious disease primarily spreading through droplet infection in dental treatment. Patient satisfaction is an indicator of healthcare quality service. Quality of healthcare service and patient satisfaction has been affected by the COVID­19 pandemic. This study aims to assess the knowledge and satisfaction toward health protocols COVID-19 during dental treatment among dental patients. METHODS: An institutional-based cross-sectional study was conducted on 270 dental patients using a self­designed questionnaire consisting of knowledge and satisfaction about health protocols COVID-19 during dental treatment through a random sampling technique. Data were imported to SPSS version 21 for analysis. Descriptive and analytical statistics were used to identify the factors associated with their knowledge and satisfaction. A p value < 0.05 was considered statistical significance. RESULTS: Totally, 270 dental patients with mean age of 37.6 ± 6.7 years participated in the study. The mean knowledge score was 36.7 ± 3.5, as considerable number of participants were unaware about the risk associated with dental treatment as well as restrictions imposed on dental procedures. About 18% of participants experienced one or other form of dental complaints during the lockdown period. The overall level of patient satisfaction was 44.6%. CONCLUSION: It can be concluded that, public knowledge is to be improved about risk of virus transmission that can be related with dental treatment and also people should be encouraged to use virtual facilities, such as teledentistry, so that no dental emergencies is left untreated during the pandemic time. In addition, the level of satisfaction was in a medium level for dental patients in the study area. Specifically, we deduced from the results that social/physical distancing measures are one of the mechanisms to decrease the fear of exposure to the COVID-19.

Clinical characteristics and risk factors for mortality in COVID-19 inpatients in Birjand, Iran: a single-center retrospective study.

BACKGROUND: The coronavirus disease 2019(COVID-19) has affected mortality worldwide. The Cox proportional hazard (CPH) model is becoming more popular in time-to-event data analysis. This study aimed to evaluate the clinical characteristics in COVID-19 inpatients including (survivor and non-survivor); thus helping clinicians give the right treatment and assess prognosis and guide the treatment. METHODS: This single-center study was conducted at Hospital for COVID-19 patients in Birjand. Inpatients with confirmed COVID-19 were included. Patients were classified as the discharged or survivor group and the death or non-survivor group based on their outcome (improvement or death). Clinical, epidemiological characteristics, as well as laboratory parameters, were extracted from electronic medical records. Independent sample T test and the Chi-square test or Fisher's exact test were used to evaluate the association of interested variables. The CPH model was used for survival analysis in the COVID-19 death patients. Significant level was set as 0.05 in all analyses. RESULTS: The results showed that the mortality rate was about (17.4%). So that, 62(17%) patients had died due to COVID-19, and 298 (83.6%) patients had recovered and discharged. Clinical parameters and comorbidities such as oxygen saturation, lymphocyte and platelet counts, hemoglobin levels, C-reactive protein, and liver and kidney function, were statistically significant between both studied groups. The results of the CPH model showed that comorbidities, hypertension, lymphocyte counts, platelet count, and C-reactive protein level, may increase the risk of death due to the COVID-19 as risk factors in inpatients cases. CONCLUSIONS: Patients with, lower lymphocyte counts in hemogram, platelet count and serum albumin, and high C-reactive protein level, and also patients with comorbidities may have more risk for death. So, it should be given more attention to risk management in the progression of COVID-19 disease.

Prognostic Factors Associated with Curing in Patients with Breast Cancer: A Joint Frailty Model.

BACKGROUND: Recurrent event data arise frequently in longitudinal medical studies. In many situations, there are a large portion of patients without any recurrences, manifesting the "zero-inflated" nature of the data. Moreover, there often exists a terminal event which may be correlated with the recurrent events. The goal of this study is to extend the application of joint frailty model to identify the prognostic factors associated with curing in patients with breast cancer. METHODS: As a prospective study, medical records of women who had been attended to Cancer Research Center, Shahid Beheshti University of Medical Sciences from January 1998 to February 2016 were reviewed. Finally, after an initial review of medical records, 711 patients were included in the study and analyzed. A checklist that included items drawn from the demographic background of patients was provided in the study. Two joint frailty models for zero-inflated recurrent events, combining a logistic model for "structural zero" status (Yes/No) and a joint frailty proportional hazards model for recurrent and terminal event times were performed to identify factors associated with BCS. RESULTS: The mean age of patients was 38.2 years. The numbers of subjects with 1, 2, 3, and 4 recurrent events were 392, 207, 97, and 15, respectively. The median follow-up time was 6.87 years. There were 137 (19.2%) deaths from cancer during the follow-up. Among the 574 patients who were censored, 418 had no tumor recurrence. Thus, there may exist a large portion of "cured" subjects. We can see that the radiation (OR = 6.02, CI = (3.87, 8.61)) and tumor size interaction with radiation (OR = 1.065, CI = (1.002-1.26)) were significant in the cure model (P < 0.05) which means that patients with smaller tumor sizes were more likely to be cured by radiation therapy. CONCLUSIONS: Our proposed models can help investigators to evaluate which treatment will result in a higher fraction of cured subjects. This is usually an important research question in biomedical studies.

Fitting logistic regression models to assess vitamin D deficiency with clinical parameters in chronic hepatitis B patients.

Statistical models provide a quantitative structure with which clinicians can evaluate their hypotheses to explain patterns in observed data and generate forecasts. In contrast, vitamin D is an important immune modulator that plays an emerging role in liver diseases such as chronic hepatitis B (CHB). Therefore, we quantified 25(OH)D3 serum levels in 292 CHB patients tested for their association with clinical parameters. Of 292 patients, 69 (63%), 95 (47%), and 39 (19%) had severe vitamin D deficiency (25(OH)D3 < 10 ng/mL), vitamin D insufficiency (25(OH)D310 and < 20 ng/mL), or adequate vitamin D serum levels (25(OH)D3 20 ng/mL), respectively. In both univariate and multivariate analyses, zinc serum level was a strong predictor of low 25(OH)D3 serum levels (P < 0.001). Results of fitted models showed that lower vitamin D levels were significantly associated with: younger age, lower uric acid levels, HBeAg-positive status, lower calcium levels (p < 0.05). Vitamin D deficiency (<20 ng/ml) or severe deficiency (<10 ng/ml) was observed more frequently among HBV patients (52%). Vitamin D deficiency was observed in most CHB patients. Generally, our results recommend that substitution of vitamin D can be a substitution method in the treatment of patients with HBV-associated disorders.

Knowledge, attitude, and practice of dentists regarding periodontal tissue health in Birjand, Northeast Iran.

Background: Determining what dentists know and believe about periodontal tissue properties is important to establish prevention practices. The present study aimed to investigate the knowledge, attitude, and practice of general dental practitioners about the properties of periodontal tissue around retainable teeth in Birjand, Northeast Iran. Methods: The knowledge, practice, and attitude of 91 dentists about periodontal tissue properties around retainable teeth were assessed by a validated researcher-made questionnaire. Results: The results showed that the mean score of dentists' attitude, knowledge, and practice were 70.7, 88.2, and 77, respectively. The mean score of the attitude of male dentists was higher than females significantly (P=0.014). Conclusion: It is highly recommended that continuing courses should be held to improve their knowledge.

Evaluation of gum health status in hemophilia patients in Birjand (a case-control study).

BACKGROUND: Gum bleeding in the absence of trauma or injury in adults with haemophilia is often reported. So hemophilic patients require special care and attention in various dentistry practices. The purpose of this study was to evaluate the gingival health status in patients with hemophilia in Birjand in 2018-2019. METHODS: Sampling was used in this case-control study to recruit cases (89 patients with hemophilia) and 89 individuals as control group recruited randomly from the general population, which were matched with cases based on gender, age and place of residence. Clinical examinations included dental health and salivary assessments. After taking informed consent from cases who had the inclusion criteria for the study, information including demographic characterizes, family history, viral infections, coagulation history, and the time of onset treatment was recorded. Oral examination was done by catheter and dental mirror. MGI (Modified gingival index) and Periodontal Index (PI) were determined for each subject. RESULTS: In this study, 84.3% of the hemophilia patients were males and 76.4% of them had a family history of hemophilia. The results show that difference between the mean of MGI and PI in hemophilic patients and healthy subjects is not statistically significant (P>0.05) while, it is higher in hemophilic patients than healthy subjects, but this difference is not statistically significant (P>0.05). Also, with increasing age, MGI and PI showed a significant increase (P<0.05). CONCLUSION: Although the higher MGI and PI index in hemophilia patients, attention to oral health and frequent control in hemophiliac is necessary. Also, to prevent dental problems and further bleeding play an important role.

Kernel and regression spline smoothing techniques to estimate coefficient in rates model and its application in psoriasis.

Background: Data types are recurrent events in studies in which each person may experience an event at different times. One of the most popular approaches to analyze recurrent event data is obtaining an estimate of the means/rate of events at different times. In this context, determining the variability over time can help better understand the effect of factor on the response. In this study, we applied smoothing methods to estimate coefficients in time-dependent rate model, and we also showed its application in data of psoriasis patients. Methods: In the present study, psoriasis patients who experienced relapse that led to hospitalization during 2005 and 2014 in the Dermatology Department of Imam Khomeini hospital in Tehran were examined. To investigate the rate of relapse during a year, time-dependent rate model was used and variability of the effects was assessed using Wald test. Both b-spline and kernel methods were used to estimate time varying coefficients in rates model. Finally, results from methods were compared based on the obtained estimates. Results: Based on the results of the Wald test, the effect of season on the occurrence of psoriasis was significantly different (p<0.01). Also according to the estimated coefficients from both b-spline and kernel methods, there was little difference between them. Conclusion: In situations in which the effect of a variable is different at different times, using time-dependent coefficients rate model can lead to a better estimate of the effect of variable on the response. On the other hand, smoothing methods can smooth the effects of the variables that vary over time.

Analysis Of Risk Factors For Nonalcoholic Fatty-Liver Disease In Hepatitis B Virus Infection: A Case-Control Study.

BACKGROUND: Nonalcoholic fatty-liver disease (NAFLD) is the most common cause of chronic liver disease worldwide. Although NAFLD has been studied extensively, potential risk factors for NAFLD among chronic hepatitis B (CHB) patients and their comparison with healthy individuals have remained understudied in Iran. As such, we examined the association between HBV infection and the development of NAFLD in two groups. METHODS: A case-control study was done on 376 CHB patients and 447 healthy subjects randomly selected from Birjand, South Khorasan province, Iran. We used logistic regression to estimate adjusted ORs with 95% CIs for incidence of NAFLD. Potential risk factors for NAFLD were evaluated while adjusting for age, sex, marital status, and educational level. Also, χ 2 was used to compare demographic characteristics between the two groups. RESULTS: A total of 373 CHB patients (mean age 40.1±12.9 years) versus 447 individuals in the control group (mean age 39.8±13.9 years) were included in this study (p=0.337). Liver characteristics were found to be significantly different in CHB and healthy groups (p<0.05). According to the results obtained from logistic regression, the adjusted OR (95% CI) for NAFLD incidence of comparing HBsAg-positive to HBsAg-negative participants was 0.62 (0.45-0.84). CONCLUSION: The results suggested that HBsAg seropositivity was associated with lower risk of developing NAFLD. This study also revealed that mild cases of fatty liver in carriers of hepatitis B are more common than in healthy subjects. However, moderate and severe cases of this condition are more common in healthy people than in hepatitis B carriers.

Prognostic factors associated with locoronal relapses, metastatic relapses, and death among women with breast cancer. Population-based cohort study.

BACKGROUND: This study was designed to identify the prognostic factors associated with two types of relapses of breast neoplasms. The aim of this study was to evaluate the association between two possible relapses for the increased incidence of distant metastases observed in patients with local relapses injuries, using multivariate statistical models. DESIGN: And Setting: A population-based cohort study that was designed as a single center: the cancer research center, Shahid Beheshti University of medical sciences. METHODS: This study was conducted on 1815 patients with breast cancer having age of 22 or more. This study considers the analysis of recurrence and survival by joint modeling of three correlated outcomes: local recurrence, distant recurrence (metastasis) and death. The goals are to find out the effects of treatments on recurrences and death, the effects of relapses on death and the correlation between local and distant recurrences. RESULTS: According to obtained results of the fitted models, the risk of local and metastatic relapses or death increased for patients with at least one positive lymph node (N+) or for patients with a grade greater than I. Also, the variable HR+ was significantly associated with the hazards of locoronal, metastatic recurrence and the death for both reduced and proposed models (P < 0.05). CONCLUSIONS: We concluded that if the association between these outcomes are not taken into account, we may lose important information. Given the small number of recurrent events, these results should be considered with caution.

Association between Multiple Recurrent Events with Multivariate Modeling: A Retrospective Cohort Study.

BACKGROUND: Recurrent event data are often encountered in biomedical research, for example, recurrent infections or recurrent hospitalizations for patients after renal transplant. In many studies, there are more than one type of events of interest. We aimed to identify the association between two types of events using multivariate joint modeling and then apply this statistical method in the clinical data set. STUDY DESIGN: A retrospective cohort study. METHODS: Overall, 342 subjects with breast cancer whose records were registered for follow-up in a Cancer Research Center at Shohadaye Tajrish Hospital, Tehran, Iran from 2006 to 2015 were investigated. These patients were monitored for at least 6 months after diagnosis and their latest status were recorded. Joint frailty model was used for modeling the relationship between two types of recurrences with Frailty package in R software. RESULTS: When the terminal event was considered as death, three-year and five-year survival rates for the patients were 0.79 and 0.68, respectively. Given the results obtained from a fitted joint frailty model, the risk of multiple recurrences (local and metastases) increased for the patients with tumor grades greater than I. CONCLUSION: With regard to the significant variance of the frailty component of the metastases event, it can be inferred that patients with the same predictive variables are prone to different levels of metastases risk and, on the other hand, given the low frequency of types of recurrences, caution should be exercised when considering the obtained results.