Investigating societal determinants of oral health—Opportunities and challenges in multilevel studies

The high prevalence of oral diseases and the persistent nature of socioeconomic inequalities in oral health outcomes across societies presents a significant challenge for public health globally. A debate exists in epidemiology on the merits of investigating population variations in health and its determinants over studying individual health and its individual risk factors. The choice of analytical unit for health outcomes at the population level has policy implications and consequences for the causal understanding of population‐level variations in health/disease. There is a lack of discussion in oral epidemiology on the relevance of studying population variations in oral health. Evidence on the role of societal factors in shaping variations in oral health at both the individual level and the population level is also mounting. Multilevel studies are increasingly applied in social epidemiology to address hypotheses generated at different levels of social organization, but the opportunities offered by multilevel approaches are less applied for studying determinants of oral health at the societal level. Multilevel studies are complex as they aim to examine hypotheses generated at multiple levels of social organization and require attention to a range of theoretical and methodological aspects from the stage of design to analysis and interpretation. This discussion study aimed to highlight the value in studying population variations in oral health. It discusses the opportunities provided by multilevel approaches to study societal determinants of oral health. Finally, it reviews the key methodological aspects related to operationalizing multilevel studies of societal determinants of oral health.     

Morphological study of the changes after sagittal split ramus osteotomy in patients with facial asymmetry: measurements of 3-dimensional modelling

The effects of bilateral sagittal split ramus osteotomy (BSSRO) on the temporomandibular joint (TMJ) are still not well understood. The aim of this study was to compare the morphological differences among unaffected subjects on the one hand, and patients with facial asymmetry before and after BSSRO on the other. Ten Chinese patients (preoperative and postoperative groups, mean (SD) age 25 (5) years) diagnosed with facial asymmetry and 10 unaffected subjects (control group, mean (SD) age 27 (5) years) were recruited prospectively. The 3-dimensional morphological measurements made on 3-dimensional models in each group were assessed by analysis-of-variance (ANOVA) and Student’s t test, and probabilities of <0.05 were accepted as significant. The horizontal condylar angle (HCA), coronal condylar angle (CCA), sagittal ramus angle (SRA), medial joint space (MJS), lateral joint space (LJS), and superior joint space (SJS) differed significantly between the preoperative and control groups (HCA: p = 0.000, CCA: p = 0.000, SRA(left/undeviated side): p = 0.002, MJS(left/undeviated side): p = 0.000, MJS(right/deviated side): p = 0.007, LJS(right/deviated side): p = 0.000, SJS(left/undeviated side): p = 0.000, SJS(right/deviated side): p = 0.000). The SRA, MJS, LJS, and SJS differed significantly between the preoperative and postoperative groups (SRA(left/undeviated side): p = 0.012, MJS(left/undeviated side): p = 0.002, LJS(right/deviated side): p = 0.021, SJS(left/undeviated side): p = 0.000, SJS(right/deviated side): p = 0.001), And the SRA, MJS, and LJS in the preoperative group differed significantly between the deviated and undeviated side (SRA: p = 0.006; MJS: p = 0.003; LJS: p = 0.011). However, there were no significant differences in the postoperative and control groups between the deviated and undeviated sides. BSSRO improved the asymmetrical morphology of the TMJ and alleviated the symptoms.     

Cancer Incidence in the Kurdistan Region of Iraq: Results of a Seven-Year Cancer Registration in Erbil and Duhok Governorates

Introduction: There are limited published data regarding the recent incidence trends of cancer in Iraqi Kurdistan. Methods: The present study assessed the epidemiological estimates of cancer incidence, as well providing a projection of future cancer trends in the upcoming decade by analysing the population-based cancer registry between 2013 and 2019, in both the Erbil and Duhok governorates. A retrospective analysis was performed on data retrieved from the Medical Statistics Department at the Ministry of Health, Kurdistan Regional Government (KRG). Results: The total number of female cancer patients was higher in both governorates, and the total incidence of patients with cancer increased by over 2x between 2013 and 2019 in Erbil and Duhok, from 73 to 174 patients/100,000 individuals for women, and 36 to 85 patients/100,000 individuals for men. Analysis indicated that the percentage of patients with cancer is projected to increase by >2x in the current decade, from 3,457 cases to 4,547 and 4,449 cases in the Erbil governorate; and from 1,365 to 2,633 and 2,737 cases in 2028 based on LSTM and bi-LTSM analysis in the Duhok governorate. Lung cancer (LC) and female breast cancer (BC) were the most prominent types of cancers diagnosed since 2013 in both the Erbil and Duhok governorates. Conclusion: The striking pattern of trends for both present and future cancer incidence rates require urgent solutions and comprehensive efforts to control risk factors that promote the increasing incidence of cancer in these two KRG governorates.     

Corrected and Republished from: Socioeconomic Predictors of Trends in Cancer Mortality Among Municipalities in Japan, 2010–2019

Background: A study investigating associations between various socioeconomic factors and standardized mortality ratios (SMR) of each type of cancer among municipalities in Japan has not been conducted using the data of the past decade. Herein, we investigated the predictors of a recent trend of municipal SMRs of cancer using the Vital Statistics in Japan and revealed the change in the SMRs depending on the identified predictors. Methods: Data on cancer mortality for each municipality in 2010 and 2019 were used. We calculated empirical Bayes SMR (EBSMR) for each municipality by type of cancer and sex and then fitted a multiple linear regression model using possible predictors in 2010 as explanatory variables and the EBSMR in 2019 as the outcome variable. We also classified municipalities into quintiles based on the values of an identified predictor in 2010, and SMRs of each type of cancer in 2010 and 2019 were calculated for each quintile. Results: The population was positively associated with EMSMRs of multiple cancer types, whereas educational level was negatively associated with EMSMRs of multiple cancer types. In addition, SMRs of municipalities with the lowest educational level deteriorated from 2010 to 2019 for many cancer types among men and women, and the difference between municipalities with the highest and lowest educational level for the SMR of cancer in all sites widened in 2019 for men. On the other hand, the SMR of municipalities with the highest educational level or the largest population tended to be higher than municipalities with lower counterparts in both 2010 and 2019 for women. Conclusion: There was a difference in the trend of the SMRs of multiple types of cancer depending on municipal educational level, whereas municipalities with larger population or educational level continued to have higher SMRs of cancer in all sites for women.     

陕西省神木县2012-2015年肿瘤发病分析

目的:分析中国西北陕西省神木县2012至2015年间癌症发病的流行特点.方法:收集2012至2015年就诊于神木县医院或外出就医返回医保机构报销例的2 752新发癌症患者,分析影响癌症发病的高危因素及年龄、性别、地域分布等流行病学特征.结果:2012至2015年4年间神木县癌症新发病例2 752例,其中男性 1 495 例(54%),女性1 257 例(46%),男女比约为1.2∶1.2012年新发555例,2013年新发593例,2014年新发673例,2015年新发931例,发病率呈逐年上升趋势.发病率居前五位的癌症分别是胃癌、肺癌、宫颈癌、食管癌和肝癌,总计新发病例1 845例,男性1 124例(61%),女性721例(39%).城镇和农村、男性和女性癌症谱有明显的差异.农村男女胃癌均明显高发于城镇,城镇男性肺癌显著高于农村男性,城镇女性乳腺癌高于农村女性.主要发病地区为神木镇、高家堡、锦界、乔岔滩、万镇.61~70岁为癌症高发年龄段.县医院就诊和外出就诊的住院天数及总花费的均数比较,都具有显著性差异.结论:神木县消化道肿瘤发病仍处于高发水平,恶性肿瘤是神木县地区威胁居民健康的重要疾病.