Does Exposure To Household and Ambient Air Pollution Pose a Risk To Cardiovascular Health? - A Cross-Sectional Study in Nepal

Over half the world’s population is exposed daily to very high levels of household air pollutants arising from burning biomass fuels; however the effects of these pollutants on cardiovascular health have not been fully established. This study aimed to compare the relationship between household indoor and outdoor air pollution with cardiovascular health in biomass and non-biomass exposed group. To compare the relationship between household indoor and outdoor air pollution with cardiovascular health in biomass and non-biomass exposed group. This cross-sectional study compared parameters of cardiovascular health in populations exposed to household indoor pollutants from biomass burning and non-biomass respectively among adults in Nepal. Data using an interviewer administered questionnaire including chest pain, blood pressure measurements and real-time measurements of household and ambient airborne particulate (PM2.5) concentrations were collected. Rural dwellers cooking with biomass fuels reported significantly more chest pain on exertion compared with non-biomass fuel users. 24-hour direct PM2.5 and CO measurements were not associated with changes in blood pressure as was the case for other measures of airborne particulate exposure except outdoor PM2.5 with men in non-biomass using households. Ambient temperature and seasonality was negatively associated with increase in blood pressure. The prevalence of both systolic (21% vs. 6%, p<0.001) and diastolic (32% vs. 7%, p<0.001) hypertension was higher amongst non-biomass fuel users compared with biomass users. There was no association between 24-hour real-time airborne pollutants data from biomass smoke and cardiovascular health effects but significantly more chest pain on exertion was found in those exposed to smoke from biomass fuel burning. Urban dwellers in Nepal were found to have higher blood pressure compared to rural dwellers, which was associated with their higher BMI levels and seasonality.

Does aspiration of saliva trigger nocturnal asthma?

Five adult asthmatics with nocturnal symptoms [mean FEV[1] 2.31 1;2 mean PD[20] histamine 1.5 unmoles], 5 asthmatics with no nocturnal symptoms [mean FEV[1] 1 2.97 1; mean PD[20] Histamine 3.7 umoles] and 5 non-asthmatic control subjects [mean FEV[1] 3.63 1; mean PD[20] histamine 78 umoles] were challenged with nebulised solutions of their own saliva or isotonic saline in a double blind crossover study to investigate whether the inhalation of saliva during sleep could cause nocturnal asthma. The maximum percent fall in FEV[1] with saliva was -26.6, -6.5 and -4.1 for the nocturnal, non-nocturnal and control groups respectively. The corresponding values for the maximum percent fall in FEV[1] with saline was -12.4, -5.5 and -3.6. The difference in maximum percent fall in FEV[1] with both saliva and saline was significant [p<0.01] for the nocturnal asthmatics when compared to the non-nocturnal asthmatics. These results lend support to the hypothesis that nocturnal symptoms in asthmatic patients may be triggered by inhalation of saliva during sleep