Environmental extreme temperature and daily preterm birth in Sabzevar, Iran: a time-series analysis

OBJECTIVES@#Most of the studies on the effect of heat stress on preterm birth (PTB) are conducted in temperate climates. Evidence on this effect in hot and arid countries with low and middle income is limited. This paper describes the short-term effect of exposure to the hot and cold environment on a daily number of PTB in Iran.@*METHODS@#The daily number of PTB was obtained from all hospitals of the city. Meteorological and air pollution data from 2011 to 2017 were obtained from a metrological station in the city. A semi-parametric generalized additive model following a quasi-Poisson distribution with the distributed lag non-linear model was selected as a modeling framework for time-series analysis to simultaneously model the short-term and lagged effect of heat stress on PTB in the Sabzevar city.@*RESULTS@#The minimum and maximum daily temperature were - 11.2 and 45.4 °C respectively. The highest risk estimate at extreme cold temperature was found for apparent temperature (relative risk (RR) 1.83; 95% CI 1.61: 2.09). This pattern was seen for both models. For extreme hot temperatures, the model with mean temperature showed the highest risk increase for both the main model and air pollution adjusted model (RR 1.36; 95% CI 1.25: 1.49). The lowest risk estimate in extremely cold conditions was found in the model with mean temperature. However, for extremely hot temperature conditions, the lowest risk estimate was found for both maximum and apparent temperature.@*CONCLUSION@#Obstetricians working in semi-arid areas should be aware of the influence of environmental extreme temperature on the incidence of PTB.

Predictors of Hepatitis B Preventive Behavioral Intentions in Healthcare Workers

BACKGROUND: Healthcare workers' practices regarding hepatitis B have an important effect on the control of this problem in workplaces. METHODS: A questionnaire-based cross-sectional study was used to investigate the role of knowledge, cues to action, and risk perceptions as predictors of preventive behavioral intentions for hepatitis B among healthcare works in Broujen, Iran (n = 150). History of hepatitis B vaccination, hepatitis B surface antigen test, and demographic characteristics were investigated. The psychometric properties of the questionnaire were established. RESULTS: Those who had a history of hepatitis B surface antigen test had a statistically significant higher level of risk perceptions (30.89 +/- 4.08 vs. 28.41 +/- 3.93, p < 0.01) and preventive behavioral intentions (5.05 +/- 1.43 vs. 4.45 +/- 1.29, p < 0.01). The mean score of cues to action was significantly correlated with age and work history (r = 0.20, p = 0.02 and r = 0.19, p = 0.02). Preventive behavioral intentions were significantly correlated with cues to action and risk perceptions but not with knowledge level. Cognitional factors were responsible for a 17% change in observed variance of preventive behavioral intentions, which was statistically significant. CONCLUSION: Risk perceptions were the most important determinant of preventive behavioral intentions for hepatitis B among health personnel; thus, emphasizing risk perceptions is recommended in educational programs aimed at increasing health personnel's practices regarding hepatitis B.

Cancer risk assessment in welder's under different exposure scenarios

Welders exposure to nickel and hexavalent chromium in welding fumes is associated with increase of cancer risk in welders. In this study we calculated cancer risk due to exposure to these compounds in welders. The role of exposure parameters in welders on derived incremental lifetime cancer risk were determined by stochastic modeling of cancer risk. Input parameters were determined by field investigation in Iranian welders in 2013 and literature review. The 90% upper band cancer risk due to hexavalent chromium and nickel exposure was in the range of 6.03E-03 to 2.12E-02 and 7.18E-03 to 2.61E-02 respectively. Scenario analysis showed that asthmatic and project welders are significantly at higher cancer risk in comparison with other welders [P<0.05]. Shift duration was responsible for 37% and 33% of variances for hexavalent chromium and nickel respectively. Welders are at high and unacceptable risk of cancer. Control measures according to scenario analysis findings are advisable