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[check mark] Vitamin D and CKD


[check mark] St. Johns wort not as effective as thought


[check mark] 4 Worsening life expectancy reported


Vitamin D Linked to Reduced Mortality Rate in Chronic Kidney Disease

A new study suggests that for patients with moderate to severe chronic kidney disease (CKD), treatment with activated vitamin D may reduce the risk of death by approximately one-fourth. Many patients with advanced CKD take the drug calcitriol, an oral form of activated vitamin D, to treat their increased levels of parathyroid hormone. Although activated vitamin D is known to influence many biological processes, until now, its effects were thought to be primarily on bone.


The new study included 1,418 patients with CKD who were in stage 3 (moderately) or stage 4 (severely) reduced kidney function. All patients also had high parathyroid hormone levels (hyperparathyroidism), which can contribute to weakening of the bones in CKD. The researchers identified one group of patients who were being treated with calcitriol to lower their parathyroid hormone levels and another group who were not receiving calcitriol. During a 2-year follow-up period, mortality rates were compared for patients who were and were not taking calcitriol. In the adjusted analysis, the overall risk of death was about 26% lower for patients taking calcitriol. Patients on calcitriol were also less likely to develop end-stage renal disease, requiring dialysis to replace lost kidney function. Overall, treatment with calcitriol was associated with a 20% reduction in the risk of either death or dialysis. The reduction in mortality with calcitriol was unrelated to its effect on parathyroid hormone levels. Thus, treatment with oral activated vitamin D may also improve survival in patients with CKD who do not yet require dialysis. The study has some important limitations, however, including lack of randomization and lack of data on other factors that may have affected survival in patients taking calcitriol. Also, because the study included mainly older, white men, the results may not apply to younger, more ethnically diverse populations who also develop CKD.


Source: Journal of the American Society of Nephrology


St. John's Wort is Not Effective for Children With Attention-Deficit/Hyperactivity Disorder

Results from a new clinical trial conducted on 54 children and adolescents (aged 6-17 years) with attention-deficit/hyperactivity disorder to determine if St. John's wort (SJW) is effective in treating their condition show that it may not be as effective at all for this purpose. The 8-week randomized, double-blind, placebo-controlled trial used the standard dose of 3 capsules per day, each containing 300 mg of SJW extract standardized to 0.3% hypericin. Although researchers concluded that SJW was no more effective than placebo in treating attention-deficit/hyperactivity disorder, they urge that more work should be done to confirm or refute these findings.


Source: JAMA


Eating Frequently is Not the Way to Weight Loss

Eating more often than 3 meals a day does not assist with weight loss, new Australian research suggests. The study found no difference in weight, waist measurement, body fat percentage, or blood sugar levels between people who ate 3 meals a day and those who ate 3 meals and 3 snacks while trying to lose weight. Many people find it hard enough to stick to a healthy eating plan to lose weight, let alone worrying about any suggested benefits of snacking or not snacking. The study involved 179 obese men and women who were all on a standard calorie-reduced diet, but with differing eating patterns. About 56% of Australians eat between 2 and 4 times a day, whereas 37% eat 5 to 7 times daily. The take-home message from these researchers was that dieters need to focus on eating fewer calories, especially when it came to snack choices, and that portion control was the key.


Source: Dieticians Association of Australia


Life Expectancy Worsening or Stagnating for Large Segment of the US Population

The US health system aims to improve the health of all people, particularly those segments of the population at greater risk of health disparities who may be unable to help themselves. The good news is that between 1960 and 2000, overall life expectancy in the United States increased by more than 7 years for men and more than 6 years for women. Now, a new, long-term study of mortality trends in selected US counties over the same 4 decades reports that these gains are not reaching many parts of the country, and in some places, life expectancy is stagnating or actually declining.


Researchers found that 4% of the male population and 19% of the female population in these counties or nationwide experienced either decline or stagnation in mortality beginning in the 1980s.


Most of the counties that had the worst downward swings in life expectancy were in the deep South, along the Mississippi River, extending into the southern portion of the Midwest and Texas and in Appalachia. The researchers analyzed mortality data from the National Center for Health Statistics and population data from the US Census Bureau that had been collected between 1959 and 2001, stopping then only because the National Center for Health Statistics stopped providing data at the county level after 2001.


The results showed that between 1961 and 1999, average life expectancy in the United States increased from 66.9 to 74.1 years for men and from 73.5 to 79.6 years for women. Looking at individual counties, however, the researchers found that beginning in the 1980s, the best-off counties continued to improve, but there was a stagnation or worsening of life expectancy in the worst-off counties-what the researchers refer to as "the reversal of fortunes." As a result, while men in the best-off counties lived 9.0 years longer than those in the worst-off counties in 1983, by 1999, that gap had increased to 11.0 years; for women, the 1983 life expectancy gap of 6.7 years increased to 7.5 years by 1999. Over the past few decades, life expectancy in high-income countries around the world has also gradually risen, with few exceptions.


The researchers also analyzed data on deaths from different diseases and found that the stagnation and worsening mortality were primarily a result of an increase in diabetes, cancers, and chronic obstructive pulmonary disease, combined with a slowdown or halt in improvements in cardiovascular mortality. The diseases that are responsible for this troubling trend seem to be most related to smoking, high blood pressure, and obesity. An increase in HIV/AIDS and homicides also played a role for men, but not for women.


Source: PLoS Medicine. April 2008, volume 5, issue 4.


No Clear Evidence for the Efficacy of Gluten- and Casein-Free Diets for Autistic Spectrum Disorder

High rates of use of complementary and alternative therapies, including gluten- and/or casein-exclusion diets, exist for children with autism. Current evidence for the efficacy of these diets is poor, however, and large-scale, good-quality randomized controlled trials (RCTs) are needed.


It has been suggested that excessive opioid activity caused by peptides from gluten and casein may have a role in causing some types of autism, based on abnormal levels of peptides in the urine and cerebrospinal fluid of some individuals with autism.


A meta-analysis was done after a search of 8 electronic databases and an examination of references in reviews on the topic. All RCTs involving programs that eliminated gluten, casein, or both gluten and casein from the diets of individuals diagnosed with an autistic spectrum disorder were examined. Because only 2 small RCTs (with <35 subjects) were identified, no meta-analysis was possible. In those 2 studies, both by the same first author, there were 3 significant treatment effects in favor of the diet intervention in regard to overall autistic traits, social isolation, and overall ability to communicate and interact. Three other outcomes were not different between the treatment and control groups, and for 10 other outcomes, the investigators could not calculate the mean differences between the 2 groups because the data were skewed. No adverse effects or harms were reported. Clearly, larger, more rigorous studies are needed of these diets before they are adopted for use.


Source: Gluten- and casein-free diets for autistic spectrum disorder [Review]. The Cochrane Collaboration


Being Overweight Does Not Decrease Sperm Production

Overweight men are not more likely to be infertile, as past research has shown is true in obese women, according to a new study. Nearly 292 very overweight men with body mass indices of 28 kg/m2, on average (which is considered quite overweight), and aged 18 to 50 years gave semen samples at fertility clinics. Impaired sperm production is the cause of infertility in 90% of infertile men, and about 6% of reproductive-age men are infertile. Greater body weight was not associated with lesser sperm production or sperm motility. Increasing body weight was linked to lower testosterone in 31 men who gave testosterone samples, although having lower testosterone levels causes infertility only if the level is very low or occurs in morbidly obese men.


Source: The Endocrine Society's Annual Meeting