Effect of periodontitis on diabetes: a review of cohort studies / 口腔疾病防治

@#Periodontitis is an inflammation that occurs in the supporting tissues around teeth with plaque biofilm as the starting factor. Periodontitis is closely related to many systemic diseases, among which the relationship between periodontitis and diabetes is the most widely reported. A cohort study is an essential clinical research method to explore the etiology. Large, well-conducted prospective cohort studies have high power, which can provide important clinical evidence for the impact of periodontitis on blood sugar control, incidence rate and complications of diabetes mellitus. Periodontitis is associated with the deterioration of glycemic control. At present, there is moderate evidence that nonsurgical periodontal treatment can significantly improve the blood sugar level of diabetes patients with periodontitis compared with no periodontal treatment. Studies on the impact of periodontitis on the incidence rate of diabetes lack consistent conclusions because of different population backgrounds. The evidence regarding whether periodontitis affects the incidence rate of diabetes complications is relatively limited. Therefore, well-designed cohort studies are needed to provide high-quality clinical evidence.

Sensitivity analysis method for unmeasured confounding interference in observational study / 中华流行病学杂志

Objective@#To introduce the methods for sensitivity analysis, discuss and compare the advantages and disadvantages of different methods.@*Methods@#The difference between confounding function method and bounding factor method in accuracy of identifying unmeasured confounding factors in observational studies through simulation trials and actual clinical data was compared.@*Results@#The results of simulation trials and actual clinical data showed that when there was unmeasured confounding between exposure (X) and outcome (Y), the results of confounding function and the bounding factor analysis were similar in terms of the effect of unmeasured confounding factor to lead to the complete change of the magnitude and direction of the observed effect value. However, the confounding function method needed smaller confounding effect to fully interpret the observed effect value than the bounding factor needed. In addition, the bounding factor method needed to analyze two confounding parameters, while only one parameter was needed in the confounding function method. The confounding function method was simpler and more sensitive than the bounding factor method.@*Conclusion@#For real-world observational data, the sensitivity analysis process is essential in analyzing the causal effects between exposure (X) and outcome (Y). In terms of the calculation process and result interpretation the sensitivity analysis method of confounding function is worth to recommend.

The relationship between knowledge of HIV, self-perceived vulnerability and sexual risk behavior among community clinic workers in Chile / Relación entre conocimientos sobre VIH, percepción de vulnerabilidad y conductas sexuales de riesgo en trabajadores de salud primaria en Chile

Objective Testing the hypothesis of an association between knowledge and sexual risk behaviour (SRB) amongst community-clinic workers in Chile, explained by the confounding effect of self-perceived vulnerability to HIV. Methods A cross-sectional survey was analyzed; it was nested within a quasiexperimental study of 720 community-clinic workers in Santiago. The SRB score combined the number of sexual partners and condom use (coded as "high"/"low" SRB). Knowledge of HIV (a 25-item index) was coded as "inadequate"/"adequate" knowledge. Self-perceived vulnerability to HIV was categorised as being "high"/ "moderate"/"low". Control variables included socio-demographics, religiousness and educational level. Percentages/averages, Chi-square tests and logistic regression (OR-estimations) were used for descriptive, association and confounding analysis. Results Respondents were 78.2 percent female, 46.8 percent married and 67.6 percent Catholic. Mean age was 38.9 (10.5 SD) and 69 percent had university/diploma level. Self-perceived HIV vulnerability was "low" in 71.5 percent cases. A negative association between knowledge and SRB was found (OR=0.55;CI=0.35-0.86), but self-perceived vulnerability did not have a confounding effect on this relationship. This relationship also persisted after being adjusted for multiple control variables (e.g. age, sex, type of primary centre, educational level, and religiousness). Conclusions Some community-clinic workers had inaccurate knowledge of HIV, which was associated with SRB. Self-perceived vulnerability did not have a confounding effect; however, future studies should further analyze occupational risk of HIV as a possible driving factor in health workers' perception of their risk. Focused training programmes should be developed to enhance basic knowledge of HIV in this group.

Objetivo Probar la asociación entre conductas sexuales de riesgo (CSR) y conocimiento de VIH en trabajadores de salud primaria en Chile, y el posible efecto de confusión de auto-percepción de vulnerabilidad hacia VIH en dicha relación. Métodos Estudio transversal anidado en estudio cuasi-experimental de 720 trabajadores de salud de Santiago. Score de CSR combinó número de parejas sexuales y uso de condón. Conocimiento de VIH fue medido mediante índice de 25 preguntas. Percepción de vulnerabilidad hacia VIH fue medida como "alta"/"moderada"/ "baja". Variables socio-demográficas, religiosidad y nivel educativo sirvieron de control. Análisis descriptivo, de asociación y confusión fueron desarrollados mediante estimación de proporciones/medias, prueba de Chi-cuadrado y regresión logística. Resultados El 78,2 por ciento de encuestados era mujer, el 46,8 por ciento estaba casado y el 67,6 por ciento era católico. Promedio de edad de 38,9 años (DS=10,5) y el 69 por ciento tenía formación universitaria/técnica. La auto-percepción de vulnerabilidad fue "baja" en el 71,5 por ciento de los trabajadores. Se observó una asociación negativa entre conocimiento y CSR (OR=0,55, IC=0,35-0,86) y la vulnerabilidad percibida no fue factor de confusión. La asociación se mantuvo tras ajustar por edad, sexo, tipo de centro primario, educación y religiosidad. Conclusiones Algunos trabajadores de salud comunitaria tenían conocimiento inadecuado de VIH, que se asoció a CSR. La auto-percepción de vulnerabilidad no fue factor de confusión, pero estudios futuros podrían analizar riesgos laborales de VIH como posible mediador en la percepción de riesgo. Programas de entrenamiento en conocimientos básicos de VIH y CSR debieran implementarse en trabajadores de salud primaria.

Application of Structural Equation Model in the Study of Therapeutic Effect of Chinese Medicine / 中国卫生统计

Objective The questionaires of the ONFH aegers who were hospitalized in Kanggu hospital,during 2005-2008 ,were collect-ed to evaluate the therapeutic effects of acupotomy by proper statistical methods. Methods Four indexes according to the criteria of Therapeutic effect of adult ONFH recovery and reconstruction (ZHAO Dewei, 1996) were measured to evaluate the effect of the treatment. Results Monofac-torial analysis showed that the treatrnent was effective,but some phenomena could not be correctly explined in specialized field. This problem was re-solved appropriately by structural equation model(SEM). Conclusion By the method of SEM, the confounding factors could be better controlled and the evaluation was more reliable.

The Relationship between Spa Visit and Quality of Life-Investigating as a confounding factor to health effects of spa- / 日本温泉気候物理医学会雑誌

Spa could have direct effects for physical and mental health but also non-daily pleasure with a visit to spa itself and surroundings. Therefore, the visit should be strongly related with quality of life (QOL) as well as general health status. First of all, this study was conducted to clarify these relationships. Secondly, the QOL was investigated as a confounding factor to health effects of spa. Subjects of this study are about all 6, 000 citizens older than 40 years of age living in Japanese J-town. Self-administrated questionnaires were distributed to the subjects at once and collected for the analysis (Response rate; 94.5%). With regard to the spa visit, (1) no visit at all recently in two or three years, (2) once a year, (3) twice or three times a year and (4) once a month, (5) twice or three times a month were classified.<br>With regard to QOL (Quality of Life), a questionnaire of WHO-QOL was used. The present study demonstrated the visitors to spa have significantly higher WHO-QOL for each subcategory; physical health, psychological status, social relationship, and environment status compared with non-visitors. Therefore, the visitors have had higher total scores of WHO-QOL compared with non-visters. With regard to past history of fracture, the visitors have had significantly lower it's prevalence compared with non-visitors. However, the significance of prevalence was cancelled in adjusting the WHO-QOL. WHO-QOL relating to the frequency of spa visit as well as the prevalence of fracture was identified as a confounding factor to health effects of spa.