ABSTRACT
Background: Falls, and more specifically, fall-related injuries, are costly to the healthcare system and can harm one's autonomy. Objectives: To study the impact of sedentary behaviour associated with fall-related injuries and how a change in sedentary behaviour may impact the risk of a fall-related injury. Design: From baseline to the first follow-up, cross-sectional and longitudinal data analysis from the Canadian Longitudinal Study of Aging (CLSA) cohort. Participants: CLSA data from 43,558 Canadians aged 45-85 were included in this study. Measurements: At baseline and follow-up, sedentary behaviour time was categorized as low (<1,080 minutes/week), moderate (1,080-1,440), or high (>1,440). Sedentary behaviour was estimated via the Physical Activity Scale for the Elderly (PASE). At follow-up, participants were dichotomized as either increased or decreased/no change in sedentary behaviour according to their categorical change between time points. Results: Sedentary behaviour was associated with fall-related injuries independently of age, sex, number of chronic conditions, and total physical activity levels OR (95%CI) 1.10 (1.05-1.15). In contrast, a change in sedentary behaviour was not associated with the risk of fall-related injury 1.00 (0.92-1.01). Conclusion: A higher level of sedentary behaviour is associated with injurious falls for people between 40 and 80 years old. However, a short-term change in sedentary behaviour does not influence the risk of injury-related falls. Despite the results, a more precise measure of sedentary behaviour is needed for epidemiology studies to capture changes over time better.
ABSTRACT
The use of phenylboronic acid (PBA) solid-phase extraction cartridges for the extraction of a range of beta-blockers from aqueous buffer and plasma has been investigated and compared with other phases commonly used for solid-phase extraction. PBA was found to provide an efficient means for the extraction of this class of compound from simple aqueous buffer systems. Extraction from buffers was pH-dependent and gave optimum results at approximately pH 8. Extraction from plasma was less efficient for some of the test compounds; this matrix effect was probably due to protein binding. Chromatography showed that plasma extracts were free of major sources of interference.