School-based programs that require mandatory physical activity do not improve the body mass index (BMI) of children who participate. However, the British Columbia researchers who made this finding stress that such programs do have other beneficial health effects, such as improving bone mass, blood pressure and aerobic capacity. The analysis involved 18 scientific studies that tested the impact of exercise programs in grades three to six, during schools hours and lasting at least six months. The findings indicate that BMI did not improve as a result of these programs. The researchers speculate this could be because the amount of exercise was insufficient to change body mass or because participants did not complete the required amount of activity. Dr. Louise Baur, an expert in child health and activity from the University of Sydney in Australia, said the results “should not negatate the importance of promoting physical activity in schools.” Baur urged implementation of community-based, long-term strategies working at multiple levels to help deal with the increase in obesity in children.

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The Internet is proving to be a powerful new tool for gathering information about the outbreak of epidemics. And the use of freely available web-based sources of information could potentially allow earlier detection of disease outbreaks at lower cost than traditional methods. This is the conclusion reached by Drs. Kumanan Wilson and John Brownstein (PhD) from the Ottawa Health Research Institute and Harvard Medical School, respectively. In reviewing the impact of the Internet on disease surveillance, Wilson and Brownstein note that Canada was a pioneer in using the Web to track disease outbreaks in the 1990s. They point to the recent listeriosis outbreak as an example of where there were clear indications on the Internet of concern about this issue before the official federal announcement.

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New mothers in British Columbia who participated in an innovative program about infant crying and shaken baby syndrome became ­significantly more knowledgeable about crying than mothers who did not participate in this pro­gram. The study was headed by researchers from the Centre for Community Child Health Research at the University of British Columbia. In the study, 1279 mothers with healthy infants were randomly assigned two weeks after they gave birth to either receiving information from the Period of PURPLE Crying ­program or standard information for parents from various societies and programs. When evaluated two months after giving birth, those who received the Period of PURPLE Crying materials scored ­higher on knowledge about infant crying and on some behaviours considered to be important in ­preventing infant shaking.

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Smoking both tobacco and marijuana seems to have a cumulative effect of increasing the risk of respiratory symptoms and chronic obstructive pulmonary disease (COPD) in adults 40 years of age and older. However, smoking marijuana alone does not seem to lead to an increased risk of respiratory symptoms or COPD. These conclusions, reached by researchers primarily based at the iCapture Centre for Cardiovascular and Pulmonary Research in Vancouver, BC, come from a survey of 878 randomly selected Vancouver residents. About half of the subjects had a history of smoking either tobacco or marijuana, or both, and 14% were current smokers. Almost one in five of the study subjects had some degree of COPD. Smokers who reported using both marijuana and tobacco were almost three times more likely than nonsmokers to have COPD.

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A comprehensive analysis of the 204 avalanche deaths that occurred in British Columbia and Alberta between 1984 and 2005 showed that traumatic injury took a heavy toll. Although asphyxia (suffocation) was responsible for three-quarters of all deaths, the research team — headed by Dr. Jeff Boyd from the department of emergency medicine, Mineral Springs Hospital, Banff — found that severe trauma was the immediate single cause of death in 24% of cases and was also present in many of the asphyxia cases. The research also found that snowmobiling and heli-skiing were involved in many of the fatal cases. Boyd and colleagues comment that the high number of head trauma cases seen in this study supports the recommendation that helmets be worn in avalanche terrain.

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