The earlier the neurological disorder multiple sclerosis is diagnosed, the better – even though there is as yet no cure.
By JUDY SIEGEL-ITZKOVICH
The earlier the neurological disorder multiple sclerosis is diagnosed, the better – even though there is as yet no cure. Researchers at Tel Aviv University have found that muscle endurance tests can detect abnormalities in the early stages of the autoimmune disease, which causes periodic attacks of limb weakness and mobility defects.While MS patients’ walking abilities and muscle strength are examined on a regular basis, doctors have yet to determine when the lower limb muscles begin to deteriorate. That’s important because with earlier identification of mobility problems, doctors would be able to implement early intervention programs. Dr. Alon Kalron and his fellow researchers from TAU’s Sackler Faculty of Medicine have discovered that specific laboratory tests for leg muscle endurance and gait – the pattern of movement while walking or running – are highly effective in identifying mobility deficits at the initial stage of MS. These deficits are difficult to discover during standard neurological testing.According to Kalron, patients in the early stages of MS had 40 percent less muscle endurance compared to their healthy counterparts. Additionally, distinct abnormalities were observed in their walking patterns. The study, which was recently published in the Journal of Neurologic Physiotherapy, could help researchers understand the mechanisms underlying the evolution of MS, and improve the management of patients afflicted with the disease, the team said.Reduced muscle endurance may be one of the earliest signs of MS and is a common complaint among patients, but it is hard to detect, said Kalron. To quantify muscle fatigue, the researchers conducted a study that included 52 patients in the early stage of MS and a control group of 28 healthy subjects.Participants, examined using a special instrument for measuring lower limb muscle strength and endurance, called an isokinetic dynamometer, were asked to attempt to bend or straighten a knee exerting maximum effort. Then they had to maintain this position for 30 seconds. Muscle fatigue was calculated by measuring the decline in muscle strength during that period. On average, those in the early stages of MS were not able to maintain their strength; they showed 40% less endurance compared to the healthy control group. In addition, patients’ gaits were observed for factors such as how far a patient spreads his legs while walking, the length of their steps and symmetry of movement. By examining walking patterns, the researchers discovered specific abnormalities in the MS group. Patients in the early stages of MS “tend to walk with a wider base, because walking with your legs further apart helps to improve stability. It’s probably a compensation strategy due to the lower muscle endurance,” explained Kalron. The participants in the MS group also walked more slowly, in an asymmetrical pattern with shorter steps.Clinicians should be more aware of possible gait and lower limb muscle deficits very early in the disease process, especially because minor impairments are difficult to detect with regular neurological examinations, he said. “The downside of detecting such deficits using advanced instruments is offset by the positive potential of early intervention programs,” suggested Kalron. “If we find the abnormalities earlier, then we can start intervention programs when they have a chance to benefit the most.”Programs based around physical therapy and fitness can help MS patients maintain higher levels of muscle endurance and improve balance, holding off the fatigue that typically accompanies the disease.OBESITY AND SHAMPOO? An association has been found by New York researchers between exposure to the chemical group known as phthalates and obesity in young children. This effect includes increased body mass index (BMI) and waist circumference.The scientists at Mount Sinai Medical Center’s children’s environmental health center studied phthalates, which are man-made, endocrine-disrupting chemicals that can mimic the body’s natural hormones. They are commonly used in shampoos, lotions, cosmetics, plastic flooring and wall coverings, food processing materials and medical devices. While poor nutrition and physical inactivity are known to contribute to obesity, a growing body of research suggests that environmental chemicals – including phthalates – could play a role in rising childhood obesity rates.
This study, published in the journal Environmental Research, was the first to examine the relationship between phthalate exposure and measurements used to identify obesity in children.“Research has shown that exposure to these everyday chemicals may impair childhood neurodevelopment, but this is the first evidence demonstrating that they may contribute to childhood obesity,” said the study’s lead author and preventive medicine expert Prof. Susan Teitelbaum. “This study also further emphasizes the importance of reducing exposure to these chemicals where possible.”The researchers measured phthalate concentrations in the urine of 387 black and Hispanic children in New York City, and recorded body measurements including BMI, height and waist circumference one year later. The urine tests revealed that over 97 percent of study participants had been exposed to phthalates typically found in personal care products, varnishes and medication or nutritional supplement coatings. The phthalates included monoethyl phthalate (MEP) and other low molecular-weight phthalates.The team also found an association between concentrations of these phthalates with BMI and waist circumference among overweight children. BMI in overweight girls with the highest exposure to MEP, for example, was 10% higher than those with the lowest MEP exposure.The percentage of obese children ages six to 11 in the US has grown from 7% in 1980 to more than 40% in 2008, according to the US Centers for Disease Control and Prevention. More than 15% of American children between the ages six and 19 are obese. In New York public schools, over one in five children in public schools are obese.