Research News
October 2010
Melatonin and sleep-related problems in children with intractable epilepsy
Sleep disturbances are common in epilepsy. To investigate the effect of melatonin on children who suffer from seizures, 23 children with intractable epilepsy and 14 children with controlled seizures were evaluated by psychometric sleep assessment and assay of diurnal and nocturnal melatonin levels. Children with intractable epilepsy received oral melatonin before bedtime and were reassessed after 3 months. Children with intractable epilepsy had higher scores for each category of sleep walking, forcible teeth grinding, and sleep apnea. At the end of therapeutic trial, patients with intractable epilepsy exhibited significant improvement in bedtime resistance, sleep duration, sleep latency, frequent nocturnal arousal, sleep walking, excessive daytime sleepiness, nocturnal enuresis, forcible teeth grinding, sleep apnea, and Epworth sleepiness scores. There was also a significant reduction in seizure severity. The use of melatonin in patients with intractable seizures was associated with improvement of many sleep-related phenomena and the severity of seizures. (Pediatr Neurol. 2010 Apr;42(4):249-54.)
Research News
November/December 2010
Low glomerular filtration rate and risk of stroke: A meta-analysis
A systematic review and meta-analysis assessed studies from 1947 to 2009, for a total of 284,672 participants (follow-up 3.2-15 years) with 7863 stroke events. Incident stroke risk increased among participants with an eGFR <60 ml/min/1.73 m2 (RR1.43, 95% CI 1.31 to 1.57; P<0.001) but not among those with an eGFR of 60-90 ml/min/1.73 m2 (1.07, 0.98 to 1.17; P=0.15). In subgroup analyses among participants with an eGFR <60 ml/min/1.73 m2, heterogeneity was significant in Asians compared with non-Asians (1.96, 1.73 to 2.23 v 1.25, 1.16 to 1.35; P<0.001). A baseline eGFR <60 ml/min/1.73 m2 was independently related to incident stroke across a variety of participants and study designs. Prompt and appropriate implementation of established strategies for reduction of vascular risk in people with known renal insufficiency may prevent future strokes. (Lee et al. BMJ. 2010 Sep 30;341:c4249.)
Research News
February/March 2011
Enteric-coated peppermint oil for irritable bowel syndrome
Peppermint is a herb with spasmolytic, carminitive properties; the active constituent, menthol, has been shown to relax smooth muscle by blocking Ca2+ channels in the gut. This was a randomized double-blind placebo-controlled study of 90 patients with irritable bowel syndrome (IBS). Subjects took one enteric coated capsule containing 0.2 ml of peppermint oil (Colpermin) or placebo three times daily 30 minutes before each meal for 8 weeks. Patients’ symptoms and quality of life were assessed after the first, fourth, and eighth weeks. The number of patients who were free from abdominal pain or discomfort changed 0 at baseline to 14 (42.5%) at week 8 in the peppermint oil group, compared to from 0 to 6 (22.2%) in the control group (P < 0.001). The severity of abdominal pain was also significantly reduced in the peppermint oil group as compared to controls (p<0.001). Peppermint oil significantly improved patients’ quality of life. There were no significant adverse reactions. The peppermint oil preparation Colpermin is safe and effective in reducing abdominal pain or discomfort in patients with IBS. (Dig Dis Sci. 2010 May;55(5):1385-90.) PMID: 19507027
Research News
Issue: April/May 2011
L-theanine in patients with schizophrenia and schizoaffective disorder
A total of 60 patients with DSM-IV schizophrenia or schizoaffective disorder participated in an 8-week, double-blind, randomized, placebo-controlled study: 400 mg/d of L-theanine was added to ongoing antipsychotic treatment from Feb 2006 until Oct 2008. Outcome measures were the Positive and Negative Syndrome Scale (PANSS), the Hamilton Anxiety Rating Scale (HARS), the Cambridge Neuropsychological Test Automated Battery (CANTAB) for neurocognitive functioning, and additional measures of general functioning, side effects, and quality of life. 40 of the 60 patients completed the study protocol. Compared to placebo, L-theanine augmentation was associated with reduction of anxiety (P = .015; measured by the HARS scale) and positive (P = .009) and general psychopathology (P < .001) scores (measured by the PANSS 3-dimensional model). According to the 5-dimension model of psychopathology, L-theanine produced significant reductions on PANSS positive (P = .004) and activation factor (P = .006) scores compared to placebo. PANSS negative and CANTAB task scores, general functioning, side effect, and quality of life measures were not affected. L-theanine augmentation of antipsychotic therapy can ameliorate positive, activation, and anxiety symptoms in schizophrenia and schizoaffective disorder patients. J Clin Psychiatry. 2011 Jan;72(1):34-42. PMID: 21208586
Research News
Issue: June/July 2011
Selenium supplementation for Hashimoto’s thyroiditis: A meta-analysis
This systematic review and meta analysis of randomized, placebo-controlled, blinded trials summarized the evidence on selenium’s effect on thyroid autoantibody titers, requirement for LT₄ replacement therapy, ultrasonographic thyroid morphology, and mood in patients with HT under LT₄ treatment. The meta analysis included 4 studies. Patients with HT assigned to Se supplementation for 3 months demonstrated significantly lower thyroid peroxidase autoantibodies (TPOab) titers (four studies, random effects weighted mean difference: −271.09, 95% CI: −421.98 to −120.19, p< 10-⁴) overall and for selenomethionine 200mcg/d, but not sodium selenite; and a significantly higher chance of reporting an improvement in well-being and/or mood (three studies, random effects risk ratio: 2.79, 95% CI: 1.21-6.47, p= 0.016) when compared with controls. Demands in LT₄ replacement therapy and ultrasonographic thyroid morphology were found either unaltered or underreported. The evidence suggests a different pattern of response to Se supplementation in HT relative to baseline TPOab titers, with a larger response in those with higher antibody levels; if confirmed, this could be used to identify which patients would benefit most from treatment. Further study is required to demonstrate an improvement in thyroid function and morphology. (Thyroid. 2010 Oct;20(10):1163-73.) PMID: 20883174
Research News
Issue: August/September 2011
High intakes of thiamine and riboflavin reduce the risk of PMS
Thiamine, riboflavin, niacin, vitamin B6, folate, and vitamin B12 are required to synthesize neurotransmitters that are potentially involved in the pathophysiology of premenstrual syndrome (PMS). A case-control study nested within the Nurses’ Health Study II cohort was conducted to evaluate whether B vitamin intake is associated with the initial development of PMS. Participants were free of PMS at baseline and after 10 years of follow up, 1057 women were confirmed as cases and 1968 were confirmed as controls. Dietary information was collected by using food-frequency questionnaires and intakes of thiamine and riboflavin from food sources were each inversely associated with incident PMS. Women in the highest quintile of riboflavin intake 2–4 years before the diagnosis year had a 35% lower risk of developing PMS than did those in the lowest quintile (P = 0.02). No significant associations between incident PMS and dietary intakes of niacin, vitamin B6, folate, vitamin B12, or vitamin B supplements were observed. The authors concluded that a significantly lower risk of PMS was noted in women with high intakes of thiamine and riboflavin from food sources only. Am J Clin Nutr. 2011 May;93(5):1080-6. PMID: 21346091
Research News
Issue: October 2011
Dose-response relation found between physical activity and cognitive function
A cross-sectional analysis examined the dose−response association between physical activity and cognitive function in Chinese subjects. A total of 27,651 participants aged 50 to 85 years were recruited from 2003 to 2008 and cognitive function was assessed by the delayed 10-word recall test (DWRT). Information on potential confounders, including demographic and anthropometric characteristics, socioeconomic position, lifestyle, and disease history, was collected by standardized interview and procedures. Most participants were classified as physically active (53.1%), with 42.4% moderately active and 4.5% physically inactive. Significant dose−response relations were found across quintiles of metabolic equivalent value (METs) with DWRT score in participants with or without good self-rated health (all p for trend < 0.001). In participants with poor self-rated heath, those in the fifth quintile of METs compared to the first quintile had a significantly reduced risk of mild cognitive impairment by 28% (p < .01; p for trend = .006). The association between physical activity and DWRT score remained significant after adjustment for depression. The authors concluded that a significant dose−response relationship between physical activity and cognitive function was found and that the association was more pronounced in participants with poor self-rated health. Ann Epidemiol. 2011 Jul 22. PMID: 21784658