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High fibre diet linked to lower risk of knee osteoarthritis

Combined findings from two long term studies indicate an association between a fibre-rich diet and a lower risk of painful knee osteoarthritis (OA). Dietary fibre is known to reduce body weight and inflammation, both of which are linked with knee OA. Researchers from Tufts University in Massachusetts mined data from two US studies to determine whether dietary fibre modifies the risks of x-ray evidence of knee OA, symptomatic knee OA (x-ray evidence and symptoms, such as pain and stiffness), and worsening knee pain. Data were taken from the Osteoarthritis Initiative (OAI; 4796 participants) and the Framingham Offspring Osteoarthritis Study (1268 participants). In both studies, dietary fibre intake was assessed at baseline with the Food Frequency Questionnaire. Information on symptoms and x-ray evidence were collected annually for 4 years (OAI) or assessed after 9 years (Framingham). Data were also gathered on potentially relevant factors, such as knee injury or surgery, medication and lifestyle, including tobacco and alcohol use and physical exercise. Of the 4051 participants in the OAI with complete data on dietary fibre intake, 869 knees were symptomatic, 152 had x-ray evidence of OA, and pain had worsened in 1964 after 4 years. In the Framingham study, of 971 participants with complete dietary fibre data, 143 knees were symptomatic and 175 displayed x-ray evidence of OA after an average 9 years. Patients with the lowest fibre intake (bottom 25% of participants) had a 30% lower risk of painful knee OA than those with the highest fibre intake (top 25%) in the OAI, and a 61% lower risk in the Framingham study. But fibre intake did not affect x-ray evidence of knee OA. In addition, the OAI found that eating more fibre in general and a high cereal fibre intake were each associated with a significantly lower risk of worsening knee pain. This was an observational study, so no firm conclusions can be drawn about cause and effect. The findings were published in the Annals of the Rheumatic Diseases.

http://dx.doi.org/10.1136/annrheumdis-2016-210810

Brain images reveal roots of kids’ increasing cognitive control

As children grow into adolescence and young adulthood, they show dramatic improvements in executive functions — the ability to control impulses, stay organised and make decisions — which are key factors in determining many outcomes, including educational success, drug use and psychiatric illness. Researchers from the University of Pennsylvania have now mapped the changes in the network organisation of the brain that underlie these improvements in executive function. The study, published in Current Biology, found that the maturing brain becomes increasingly segregated into distinct network modules for greater efficiency. The findings show that the degree to which executive function improves with age depends on the degree to which the well defined modular network structure emerges. The researchers used data from a sample of 882 people aged 8–22 years who completed diffusion imaging as part of the Philadelphia Neurodevelopmental Cohort, a community-based study of brain development that includes rich neuroimaging and cognitive data. As expected, executive function improved markedly with age. An analysis of the brain images revealed an increasingly specialised and modular structure that was nonetheless fully integrated. The findings suggest that modular brain architecture is critical for the development of complex cognition and behaviour. They may also lead to the identification of biomarkers of abnormal brain development that could predict risk for psychosis and major mood disorders, the researchers say. They suggest that a globally integrated network architecture may be critical for supporting specialised processing and reducing interference between brain systems. At the same time, the increase in global integration may allow specialised systems to work together in a coordinated fashion. The researchers also found a relationship between the emergence of modular structures and a person’s performance on tests of executive function.

http://dx.doi.org/10.1016/j.cub.2017.04.051