Passive smoking linked to behavioural disorders; ADHD stress shortens lives
French researchers find an association between tobacco exposure and the risk of emotional and conduct disorders in children exposed to passive smoking in the womb and in life.
Early exposure to tobacco as a cause of behavioural problems
Passive smoking has well-known effects on health, and a new study has found it could also cause behavioural disorders in children. Researchers from Inserm and Pierre and Marie Curie University, in collaboration with the university hospitals of six French cities, analysed data on pre- and postnatal exposure to tobacco in the homes of 5,200 primary-school children. Behavioural disorders were assessed via the Strengths and Difficulties Questionnaire used to assess the behavioural and psychosocial functioning of the children, which was also completed by the parents. The researchers found an association between tobacco exposure and the risk of emotional and conduct disorders in children. The association exists in cases of prenatal or postnatal exposure alone, but is stronger with exposure during both periods. During pregnancy, nicotine in tobacco smoke stimulates acetylcholine receptors, and causes structural changes in the brain. In the first months of life, exposure to tobacco smoke generates a protein imbalance that leads to altered neuronal growth, the researchers explain.
ADHD may shorten lives of children and their mothers
Hyperactive children and their mothers are more likely to have chromosome changes associated with an increased risk for chronic diseases and conditions such as diabetes, obesity and cancer, according to a new study by Brazilian scientists. The study assessed the length of telomeres - the caps at the ends of chromosomes that act as protection against the loss of protein-coding DNA during cell division - in 61 children, aged between six and 16, who were diagnosed with attention deficit hyperactivity disorder (ADHD) and in their parents. Telomeres shorten naturally with ageing, but the process is accelerated by psychological and biological stress. The shorter the telomeres, the shorter one's life expectancy. The children in the study were found to have shorter telomeres than those that would be expected for their ages. Although mothers' telomeres were also shorter, they did not find any alteration in the fathers' telomere length. The researchers believe the phenomenon is due to the stress that ADHD symptoms generate for the children and their mothers.
Walk around office can reverse effects of hours at a computer
Have you been sitting down at your desk for most of your working day? Get up and walk around for 10 minutes. It is known that prolonged sitting can have a negative impact on heart health, but a new study shows even a walk this short is enough to reverse the detrimental consequences. Researchers from the University of Missouri's school of medicine compared the vascular function of 11 healthy young men before and after an extended period of sitting and found that blood flow in the popliteal - an artery in the lower leg - was greatly reduced after sitting at a desk for six hours. "When you have decreased blood flow, the friction of the flowing blood on the artery wall, called shear stress, is also reduced," says Jaume Padilla, the study's lead author. "Moderate levels of shear stress are good for arterial health, whereas low levels of shear stress appear to be detrimental and reduce the ability of the artery to dilate. Dilation is a sign of vascular health. The more the artery can dilate and respond to stimuli, the healthier it is."