<?xml version="1.0" encoding="utf-8"?>
<recommendedContent xmlns="http://api.mspoke.com">
    <recommendedItem id="20100101_19_473"
                     title="AAN: High Intake of Vitamin D Linked to Lower MS Risk (CME/CE)"
                     score="0.012"
                     href="http://www.medpagetoday.com/MeetingCoverage/AAN/tb/18406?impressionId=1265817563480"
                     
      &lt;p&gt;TORONTO  --  Women whose mothers consumed high levels of vitamin D during pregnancy have a lower risk of developing multiple sclerosis, a large, observational study confirmed.&lt;/p&gt;
&lt;p&gt;Mothers who reported the highest intake during pregnancy were 45% less likely to have a daughter who subsequently developed the disease than those who consumed the least vitamin D (RR 0.55, 95% CI 0.35 to 0.88), according to Fariba Mirzaei, MD, MPH, a doctoral student at the Harvard School of Public Health.&lt;/p&gt;
&lt;p&gt;Mirzaei is scheduled to report the findings at the American Academy of Neurology (AAN) meeting in April.&lt;/p&gt;
&lt;p&gt;Lily Jung, MD, a neurologist at Swedish Medical Center in Seattle, said in an interview that the study &quot;adds more fuel to the fire that low vitamin D is important in the genesis of MS,&quot; which has been demonstrated in previous studies. (See &lt;a href=&quot;http://www.medpagetoday.com/Neurology/MultipleSclerosis/4738&quot; mce_href=&quot;http://www.medpagetoday.com/Neurology/MultipleSclerosis/4738&quot; target=&quot;_blank&quot;&gt;High Blood Levels of Vitamin D May Lower MS Risk&lt;/a&gt;)&lt;/p&gt;
&lt;p&gt;She said it&apos;s unclear why vitamin D is associated with risk of multiple sclerosis.&lt;/p&gt;
&lt;p&gt;&quot;There&apos;s an idea that perhaps there might be receptors that are turned on by vitamin D levels that give some form of protection, but that is very preliminary information and we&apos;re still learning a lot about that,&quot; said Jung, who is also a spokeswoman for the AAN.&lt;/p&gt;
&lt;p&gt;Although the link between vitamin D and risk of multiple sclerosis has been demonstrated before, gestational exposure to the vitamin has not been studied.&lt;/p&gt;
&lt;p&gt;To fill that gap, Mirzaei analyzed data from the Nurses&apos; Mothers&apos; Study, which includes a subcohort of the two Nurses&apos; Health Studies that was restricted to nurses whose biological mothers completed a questionnaire in 2001 about their diet during pregnancy.&lt;/p&gt;
&lt;p&gt;The current analysis included 35,794 nurse-mother pairs.&lt;/p&gt;
&lt;p&gt;During the 16-year study period, 199 of the nurses were diagnosed with multiple sclerosis.&lt;/p&gt;
&lt;p&gt;In addition to a lower risk of disease among those whose mothers consumed the largest amounts of vitamin D, those whose mothers had the highest predicted serum 25-hydroxyvitamin D levels also had a reduced risk of having a daughter with the disease (RR 0.58, 95% CI 0.37 to 0.90).&lt;/p&gt;
&lt;p&gt;In an analysis of milk drinking alone, mothers who drank at least four glasses a day had a nonsignificant reduced risk of having a daughter who would develop multiple sclerosis compared with those who drank less than three glasses a month (RR 0.44, 95% CI 0.16 to 1.23).&lt;/p&gt;
&lt;p&gt;However, there was a significant trend for lower risk of multiple sclerosis with increasing milk consumption (&lt;em&gt;P&lt;/em&gt;=0.001).&lt;/p&gt;
&lt;p&gt;Jung noted that the study was limited by the use of questionnaires decades after a pregnancy to determine dietary intake of vitamin D.&lt;/p&gt;
&lt;p&gt;Nevertheless, she said, &quot;this is very consistent with what we&apos;re seeing elsewhere in terms of vitamin D in moms and the risk of MS in kids.&quot;&lt;/p&gt;
&lt;div style=&quot;float:left;border-style:solid;border-width:1px;border-color:#8dabbc;font-family:arial;font-size:12px;background-color:#DBE9F2;padding:5px;&quot;&gt;&lt;p&gt;Mirzaei did not make any financial disclosures.&lt;/p&gt;&lt;/div&gt;&lt;div style=&quot;clear:both;&quot;&gt;&lt;/div&gt;
    </recommendedItem>
    <recommendedItem id="20100101_19_444"
                     title="Huntington Drug Produces Slight Benefit (CME/CE)"
                     score="0.012"
                     href="http://www.medpagetoday.com/Neurology/GeneralNeurology/tb/18363?impressionId=1265817563480"
                     
      &lt;p&gt;An investigational drug that protects mitochondria in nerve cells helped restore some cognitive function in patients with Huntington&apos;s disease, researchers said.&lt;/p&gt;
&lt;p&gt;Patients receiving three months of treatment with latrepirdine (Dimebon), formerly known as dimebolin, showed a mean increase of 0.86 points (SD 0.31) on the Mini-Mental State Exam (MMSE), compared to an average decline of 0.12 points (SD 0.31,&lt;em&gt; P&lt;/em&gt;=0.03) in a placebo group, Karl Kieburtz, MD, MPH, at the University of Rochester in Rochester, N.Y., and colleagues reported in the February &lt;em&gt;Archives of Neurology&lt;/em&gt;.&lt;/p&gt;
&lt;p&gt;The treatment was also well tolerated in the 91-patient randomized trial, though no differences from placebo were seen in other measures of efficacy, including the Unified Huntington&apos;s Disease Rating Scale and the cognition component of the Alzheimer&apos;s Disease Assessment Scale.&lt;/p&gt;
&lt;p&gt;Kieburtz and colleagues concluded that latrepirdine &quot;may have a beneficial effect on cognition&quot; in Huntington&apos;s disease patients and that additional trials are warranted.&lt;/p&gt;
&lt;p&gt;Latrepirdine stabilizes the mitochondrial membrane in neurons. Disruption in the membrane leads to neuronal apoptosis and appears to play a role in neuron death associated with several neurodegenerative syndromes, including Huntington&apos;s and Alzheimer&apos;s diseases, the authors noted.&lt;/p&gt;
&lt;p&gt;&quot;Nonclinical data available to date suggest that the mechanism of action of latrepirdine is to enhance mitochondrial function in the setting of cellular stress,&quot; Kieburtz and colleagues explained in the report.&lt;/p&gt;
&lt;p&gt;A phase III study of latrepirdine in Alzheimer&apos;s disease, &lt;a href=&quot;http://www.medpagetoday.com/Geriatrics/AlzheimersDisease/10174&quot; mce_href=&quot;http://www.medpagetoday.com/Geriatrics/AlzheimersDisease/10174&quot; target=&quot;_blank&quot;&gt;reported in 2008&lt;/a&gt;, produced modest benefits. Two additional phase III trials were started late last year, according to the drug&apos;s co-developers, Medivation and Pfizer.&lt;/p&gt;
&lt;p&gt;The drug was once sold in Russia as a nasal decongestant, but is no longer available anywhere.&lt;/p&gt;
&lt;p&gt;The drug&apos;s generic name was originally dimebolin but the companies requested the change to latrepirdine last year.&lt;/p&gt;
&lt;p&gt;In the current study, designed primarily as a safety assessment, Kieburtz and colleagues randomized middle-age patients with mild to moderate Huntington&apos;s disease symptoms to either placebo or 20 mg of latrepirdine three times daily.&lt;/p&gt;
&lt;p&gt;Adverse events of various types were reported in 70% of the latrepirdine patients and 80% of the placebo group. Falls, headache, dizziness, nausea, and chorea were the most common in both groups, with no significant differences in rates between the drug and placebo.&lt;/p&gt;
&lt;p&gt;Headache (three cases) and somnolence (three cases) were somewhat more common with latrepirdine than with placebo ( three cases and one case, respectively).&lt;/p&gt;
&lt;p&gt;On none of the 11 motor or cognitive components of the Unified Huntington&apos;s Disease Rating Scale did patients receiving latrepirdine show a significant difference from the placebo group.&lt;/p&gt;
&lt;p&gt;Patients showed similar declines in mean scores on the Alzheimer&apos;s Disease Assessment Scale&apos;s cognitive component, both decreasing about one point from a mean at baseline of 20.&lt;/p&gt;
&lt;p&gt;Mean baseline scores on the MMSE were 25.3. The 0.97-point advantage of latrepirdine over placebo in this measure after 90 days was statistically significant (95% CI 0.10 to 1.85), although the clinical change was relatively small.&lt;/p&gt;
&lt;p&gt;However, Kieburtz and colleagues expressed surprise at finding any significant difference in this measure, &quot;given that the MMSE is generally considered a relatively insensitive measure of cognitive function.&quot;&lt;/p&gt;
&lt;p&gt;They indicated that the MMSE provides a broader measure of cognitive function than either the Huntington- or Alzheimer-specific instruments. The Unified Huntington&apos;s Disease Rating Scale is intended for monitoring long-term changes in function, rather than the effects of a short-term intervention such as this one, the researchers argued.&lt;/p&gt;
&lt;p&gt;They added that the Alzheimer assessment may not fully capture the cognitive domains most affected in Huntington&apos;s disease.&lt;/p&gt;
&lt;p&gt;Kieburtz and colleagues also pointed out that the improvements seen with latrepirdine were similar to those found in the earlier trial in Alzheimer&apos;s disease.&lt;/p&gt;
&lt;p&gt;The small number of patients and the relatively short treatment duration were limitations of the study.&lt;/p&gt;
&lt;div style=&quot;float:left;border-style:solid;border-width:1px;border-color:#8dabbc;font-family:arial;font-size:12px;background-color:#DBE9F2;padding:5px;&quot;&gt;&lt;p&gt;The study was funded by Medivation.&lt;/p&gt;&lt;p&gt;Study authors reported relationships other than research support with Medivation, Abbott Laboratories, Biogen Idec, Ceregene, EMD Serono, FoldRx, Impax, Ipsen, Eli Lilly, Lundbeck, Merz, NeuroSearch, Novartis, Orion Health, Prestwick Pharmaceuticals, Schering-Plough, Solvay SA, Teva, UCB Pharma, Pfizer, and the Welding Rod Litigation defendants.&lt;/p&gt;&lt;p&gt;Two co-authors were employees of Medivation.&lt;/p&gt;&lt;/div&gt;&lt;div style=&quot;clear:both;&quot;&gt;&lt;/div&gt;
    </recommendedItem>
    <recommendedItem id="20100101_19_430"
                     title="HRT Linked to Asthma Risk (CME/CE)"
                     score="0.012"
                     href="http://www.medpagetoday.com/Endocrinology/Menopause/tb/18342?impressionId=1265817563480"
                     
      &lt;p&gt;Estrogen-only hormone replacement therapy is associated with an increased risk of asthma in postmenopausal women, a large prospective observational cohort study showed.&lt;/p&gt;
&lt;p&gt;Recent and current users of estrogen had a 54% increase in the risk of being diagnosed with asthma, according to Isabelle Romieu, MD, ScD, of the National Institute of Public Health in Cuernavaca, Mexico, and colleagues.&lt;/p&gt;
&lt;p&gt;The risk was even higher in nonsmokers or those who reported an allergic disease before they developed asthma, the researchers reported online in &lt;em&gt;Thorax&lt;/em&gt;.&lt;/p&gt;
&lt;p&gt;Epidemiological studies suggest that an endocrine mechanism  --  perhaps endogenous estrogen synthesis  --  is involved in asthma in women and girls, the researchers wrote.&lt;/p&gt;
&lt;p&gt;It&apos;s plausible that hormone replacement therapy &quot;might therefore play a role in asthma onset,&quot; they theorized in the journal.&lt;/p&gt;
&lt;p&gt;To delve into the question, Romieu and colleagues turned to the E3N cohort study, which is the French component of the continuing European Prospective Investigation into Cancer and Nutrition (EPIC) study.&lt;/p&gt;
&lt;p&gt;The study started in 1990 and includes 98,995 French women born between 1925 and 1950. The participants complete self-administered questionnaires every two years, giving details of their medical history, menopausal status, and a variety of lifestyle characteristics.&lt;/p&gt;
&lt;p&gt;Women were deemed to have a new case of asthma if  --  after being free of the disease at baseline  --  they later reported both that they had suffered asthma attacks and that the diagnosis had been confirmed by a physician.&lt;/p&gt;
&lt;p&gt;Among the participants, Romieu and colleagues found 57,664 women who were free of asthma at menopause. In that group, the researchers found, there were 569 incident cases of asthma during a total of 495,448 years of follow-up.&lt;/p&gt;
&lt;p&gt;Analysis showed that hormone replacement therapy in general was related to an increased risk of asthma onset among recent users, with a hazard ratio of 1.20. But the 95% confidence interval ranged from 0.98 to 1.46, so the finding was not statistically significant.&lt;/p&gt;
&lt;p&gt;Instead, the researchers found, the association only reached significance among women reporting the use of estrogen alone, where the hazard ratio was 1.54, with a 95% confidence interval from 1.13 to 2.09.&lt;/p&gt;
&lt;p&gt;The risk was particularly great in estrogen-using women who had never smoked or who had reported allergic disease before the asthma onset. Those hazard ratios were 1.80 and 1.84, respectively, and both reached significance.&lt;/p&gt;
&lt;p&gt;The increased risk among never smokers might reflect an anti-estrogen effect of tobacco smoke, the researchers speculated, or difficulty isolating the additional effect of the therapy in smokers.&lt;/p&gt;
&lt;p&gt;The strengths of the study include its large size, prospective design, and relatively low loss to follow-up of 3.8%, Romieu and colleagues said.&lt;/p&gt;
&lt;p&gt;They added that the results might be biased if users of hormone replacement therapy reported more asthma attacks or were diagnosed more often because of more frequent visits to the doctor.&lt;/p&gt;
&lt;p&gt;Indeed, hormone therapy users had more mammograms than nonusers, they noted, but added that the participants all had free medical care and &quot;there is no reason to believe&quot; that hormone users had more medical visits for non-gynecological reasons than nonusers.&lt;/p&gt;
&lt;p&gt;Hormone therapy has been controversial  --  and on the decline  --  since the landmark Women&apos;s Health Initiative study was stopped in 2002 when the researchers found that participants taking estrogen plus progestin had a greater incidence of coronary heart disease, breast cancer, stroke, and pulmonary embolism than those receiving placebo.&lt;/p&gt;
&lt;p&gt;In the current study, the combination hormone therapy was not associated with an increase in asthma incidence.&lt;/p&gt;
&lt;div style=&quot;float:left;border-style:solid;border-width:1px;border-color:#8dabbc;font-family:arial;font-size:12px;background-color:#DBE9F2;padding:5px;&quot;&gt;&lt;p&gt;The study and researchers had support from Mutuelle G&amp;#233;n&amp;#233;rale de l&apos;Education Nationale, the Institut de Canc&amp;#233;rologie Gustave Roussy, the Institut National de la Sant&amp;#233; et de la Recherche M&amp;#233;dicale, the CDC, the Canc&amp;#233;rop&amp;#244;le R&amp;#233;gion Ile de France, and the GA&lt;sup&gt;2&lt;/sup&gt;LEN project.&lt;/p&gt;&lt;p&gt;The authors did not report any potential conflicts.&lt;/p&gt;&lt;/div&gt;&lt;div style=&quot;clear:both;&quot;&gt;&lt;/div&gt;
    </recommendedItem>
    <recommendedItem id="20100101_19_390"
                     title="Vegetative State May Still Harbor Consciousness (CME/CE)"
                     score="0.01"
                     href="http://www.medpagetoday.com/Neurology/GeneralNeurology/tb/18283?impressionId=1265817563480"
                     
      Researchers in England are reporting they have been able to establish limited communication with a man in a persistent vegetative state by using functional magnetic resonance imaging (fMRI).&lt;br&gt;
&lt;br&gt;The 34-year-old man was able to answer simple Yes or No questions by imagining different types of activity, which caused changes in brain activity that could be seen in the machine, according to Martin Monti, PhD, of the Medical Research Council Cognition and Brain Sciences Unit in Cambridge, England, and colleagues.&lt;br&gt;
&lt;br&gt;The finding shows that at least some patients who are otherwise unresponsive may have some residual awareness, the researchers reported online in the &lt;em&gt;New England Journal of Medicine&lt;/em&gt;.&lt;br&gt;
&lt;br&gt;&quot;The incredible thing is that we could never do something like that at the bedside,&quot; Monti told &lt;em&gt;MedPage Today&lt;/em&gt;. Outside of the fMRI machine, he said, the patient remained unresponsive to standard tests.&lt;br&gt;
&lt;br&gt;The study is likely to arouse controversy, Monti conceded, especially in the light of such high-profile cases as that of Terry Schiavo, which eventually went to the U.S. Supreme Court.&lt;p&gt;&lt;/p&gt;
&lt;p&gt;In the Schiavo case, relatives were bitterly divided on whether to withdraw&lt;strong&gt; &lt;/strong&gt;life support for the woman, who had been in a persistent vegetative state for several years.&lt;/p&gt;
&lt;p&gt;&quot;People will have a tendency to overinterpret this,&quot; Monti said, adding &quot;this finding in one patient does not imply that all patients may or may not have the ability to do this.&quot;&lt;/p&gt;
&lt;p&gt;Indeed, the researchers tested 54 people and found only five who could apparently respond to direction by imagining either motor or spatial activity. Imagining those activities uses different parts of the brain and their activation can be seen by the fMRI scan.&lt;/p&gt;
&lt;p&gt;Several of the responders were already what is called &quot;minimally responsive,&quot; meaning that occasionally they were able to react to external stimuli.&lt;/p&gt;
&lt;p&gt;Of those five, the researchers only tried to communicate with one  --  the man in a persistent vegetative state  --  using his ability to reliably activate different brain areas when asked to imagine either playing tennis or looking around a room in his house.&lt;/p&gt;
&lt;p&gt;While in the machine, he was asked simple questions, such whether his father&apos;s name was Alexander. To answer Yes, he was to imagine playing tennis, while for No he was to imagine looking around the room.&lt;/p&gt;
&lt;p&gt;He was able to answer five out of six questions, the researchers reported, adding it was unclear why he was unable to answer the sixth but no brain activity was seen in response to the question.&lt;/p&gt;
&lt;p&gt;Outside experts also cautioned against overinterpreting the results.&lt;/p&gt;
&lt;p&gt;&quot;The percentage of patients showing a response was low, and longer-term follow-up studies are needed to determine whether such fMRI findings by themselves have meaningful predictive value,&quot; argued Alan Faden, MD, of the University of Maryland School of Medicine in Baltimore.&lt;/p&gt;
&lt;p&gt;&quot;This study may well raise questions for some with regard to medical or legal decisions based upon state of consciousness,&quot; Faden said in an e-mail, &quot;but the findings primarily underscore the limitations of current categorizations for diminished states of consciousness.&quot;&lt;/p&gt;
&lt;p&gt;He said that as technology gets better, it will likely mean that doctors will have to modify their diagnostic categories for what he called &quot;states of diminished consciousness.&quot;&lt;/p&gt;
&lt;p&gt;In an accompanying editorial in the journal, Allan Ropper, MD, of Brigham and Women&apos;s Hospital in Boston, wrote that such research is &quot;easily subject to overinterpretation and sensationalism.&quot;&lt;/p&gt;
&lt;p&gt;He cautioned that brain activation was seen only in a few patients and only in those with a traumatic brain injury, rather than global ischemia and anoxia.&lt;/p&gt;
&lt;p&gt;And, he wrote, the brain activity seen in the patients is not evidence of such things as memory, self-awareness, anxiety, or despair. &quot;We cannot be certain whether we are interacting with a sentient, much less a competent, person&quot; Ropper wrote.&lt;/p&gt;
&lt;p&gt;Despite such caveats, the research is &quot;critically important,&quot; according to Michael DeGeorgia, MD, of University Hospitals Case Medical Center in Cleveland.&lt;/p&gt;
&lt;p&gt;It &quot;illustrates both the complexities of this area and the limitations of our bedside clinical examination,&quot; he said in an e-mail, adding that more research will be needed to figure out how to use the technology and how to interpret the results.&lt;/p&gt;
&lt;p&gt;The research &quot;does raise difficult medical and legal questions,&quot; DeGeorgia said.&lt;/p&gt;
&lt;p&gt;&quot;We always need to be upfront and honest with families about what we know for certain and what we do not know for certain,&quot; he said. &quot;In many of these cases, the honest answer is that we cannot be absolutely 100% certain that their loved one isn&apos;t &apos;in there somewhere.&apos;&quot;&lt;/p&gt;
&lt;div style=&quot;float:left;border-style:solid;border-width:1px;border-color:#8dabbc;font-family:arial;font-size:12px;background-color:#DBE9F2;padding:5px;&quot;&gt;&lt;p&gt;The study had support from the Medical Research Council, the European Commission, Fonds de la Recherche Scientifique, the James S. McDonnell Foundation, the Mind Science Foundation, the Reine Elisabeth Medical Foundation, the Belgian French-Speaking Community Concerted Research Action, University Hospital of Liege, the University of Liege, and the National Institute for Health Research Biomedical Research Centre.&lt;/p&gt;&lt;p&gt;The researchers said they had no potential conflicts.&lt;/p&gt;&lt;p&gt;Hopper did not report any conflicts.&lt;/p&gt;&lt;/div&gt;&lt;div style=&quot;clear:both;&quot;&gt;&lt;/div&gt;&lt;p&gt;&lt;em&gt;This article was developed in collaboration with ABC News. &lt;/em&gt;&lt;img src=&quot;http://www.medpagetoday.com/upload/2009/10/1/14357_1.jpg&quot; mce_src=&quot;http://www.medpagetoday.com/upload/2009/10/1/14357_1.jpg&quot; alt=&quot;&quot;&gt;&lt;/p&gt;
    </recommendedItem>
    <recommendedItem id="20100101_19_372"
                     title="Low Serotonin Eyed as Mechanism for SIDS (CME/CE)"
                     score="0.009"
                     href="http://www.medpagetoday.com/Neurology/GeneralNeurology/tb/18262?impressionId=1265817563480"
                     
      Low brainstem levels of serotonin and the enzyme that makes it could underlie sudden infant death syndrome (SIDS), researchers suggested.&lt;br&gt;
&lt;br&gt;In an autopsy study, SIDS cases showed 26% lower serotonin levels in two major components of the medulla&apos;s serotonin system  --  the raph&amp;#233; obscurus (&lt;em&gt;P&lt;/em&gt;=0.05) and paragigantocellularis lateralis (&lt;em&gt;P&lt;/em&gt;=0.04)  --  compared with age-adjusted controls who died from known causes.&lt;br&gt;
&lt;br&gt;These brainstem circuits control breathing, blood pressure, and heart rate during sleep, Hannah C. Kinney, MD, of Children&apos;s Hospital Boston, and colleagues reported in the Feb. 3 issue of the &lt;em&gt;Journal of the American Medical Association&lt;/em&gt;.&lt;br&gt;
&lt;br&gt;A baby with an abnormality in control of these systems might not be able to respond to a life-threatening challenge like asphyxia by rousing from sleep or turning its head the researchers explained.&lt;p&gt;&lt;/p&gt;
&lt;p&gt;SIDS occurs in the &quot;critical first year of life, when homeostatic systems are still maturing,&quot; they noted.&lt;/p&gt;
&lt;p&gt;Mary McClain, RN, MS, of Boston University Medical Center, who counsels families that have lost a baby to SIDS, commented that these findings help establish the biological basis for urging parents to place their babies on their backs to sleep.&lt;/p&gt;
&lt;p&gt;The researchers obtained tissue samples from autopsies of 41 children who died from SIDS, seven who died acutely from known causes (including a car accident, drowning, pneumonia, and unsuspected congenital heart disease), and five who died in the hospital with chronic conditions causing hypoxia-ischemia.&lt;/p&gt;
&lt;p&gt;SIDS cases had mean serotonin levels of 31.4 pmol/mg of protein in the paragigantocellularis lateralis, compared with 40.0 pmol/mg among the controls who died acutely (&lt;em&gt;P&lt;/em&gt;=0.04).&lt;/p&gt;
&lt;p&gt;Levels averaged 55.4 versus 75.5 pmol/mg of protein, respectively, in the raph&amp;#233; obscurus (&lt;em&gt;P&lt;/em&gt;=0.05).&lt;/p&gt;
&lt;p&gt;These abnormalities in the medulla did not appear to involve the catecholamine system. Catecholamine levels were similar between SIDS cases and controls.&lt;/p&gt;
&lt;p&gt;Nor was there evidence for excessive degradation of dopamine or neurotransmitter turnover in SIDS cases, supporting the idea that the key abnormality is reduced synthesis of serotonin, the researchers said.&lt;/p&gt;
&lt;p&gt;Another marker of serotonin function  --  tryptophan hydroxylase (TPH2), the key enzyme involved in synthesis of serotonin  --  also supported this conclusion, with 22% lower levels in the raph&amp;#233; obscurus in SIDS than in controls (&lt;em&gt;P&lt;/em&gt;=0.03).&lt;/p&gt;
&lt;p&gt;Serotonin receptor binding was 29% to 55% lower in three medullary nuclei that receive serotonin projections, notable for a decrease in binding with older age in SIDS cases, but not controls, the researchers noted.&lt;/p&gt;
&lt;p&gt;Given similar findings in three previous investigations, this &quot;may reflect a progressive decrease with age in those infants with the &apos;SIDS abnormality,&apos;&quot; they wrote. Or it&apos;s possible that those with a &quot;stronger abnormality take longer to outgrow the risk period for SIDS and continue to die at older ages,&quot; Kinney&apos;s group wrote.&lt;/p&gt;
&lt;p&gt;Likewise, serotonin receptor binding in infants who died from SIDS was significantly lower in those without known risk factors for SIDS, such as &lt;a href=&quot;http://www.medpagetoday.com/Pediatrics/GeneralPediatrics/17365&quot; mce_href=&quot;http://www.medpagetoday.com/Pediatrics/GeneralPediatrics/17365&quot; target=&quot;_blank&quot;&gt;sleeping face down&lt;/a&gt;, &quot;suggesting that additional risk factors are necessary to precipitate death when the medullary serotonin system is less compromised,&quot; they added.&lt;/p&gt;
&lt;p&gt;Although repetitive apnea and agonal &lt;a href=&quot;http://www.medpagetoday.com/Pulmonology/SleepDisorders/2817&quot; mce_href=&quot;http://www.medpagetoday.com/Pulmonology/SleepDisorders/2817&quot; target=&quot;_blank&quot;&gt;impaired gasping&lt;/a&gt; before death have been reported in some SIDS cases, chronic impaired oxygenation in the hospitalized children in the study produced a very different serotonin pattern than that seen in SIDS.&lt;/p&gt;
&lt;p&gt;Children who died with chronic hypoxia conditions had 55% higher serotonin levels in the raph&amp;#233; obscurus (&lt;em&gt;P&lt;/em&gt;=0.02) and 126% higher levels in the paragigantocellularis lateralis (&lt;em&gt;P&lt;/em&gt;=0.002) than the SIDS cases.&lt;/p&gt;
&lt;p&gt;They also had 640% higher dopamine levels in the raph&amp;#233; obscurus than the SIDS cases (&lt;em&gt;P&lt;/em&gt;=0.006).&lt;/p&gt;
&lt;p&gt;This suggested &quot;that the primary mechanisms underlying serotonin abnormalities in SIDS are not mediated by chronic hypoxia-ischemia,&quot; Kinney&apos;s group wrote.&lt;/p&gt;
&lt;p&gt;The researchers cautioned that their neurotransmitter measurements may have been off somewhat due to prolonged postmortem intervals.&lt;/p&gt;
&lt;p&gt;They also warned that the study was limited by inability to perform these measurements at the synapse in postmortem tissues and by the small sample of controls.&lt;/p&gt;
&lt;div style=&quot;float:left;border-style:solid;border-width:1px;border-color:#8dabbc;font-family:arial;font-size:12px;background-color:#DBE9F2;padding:5px;&quot;&gt;&lt;p&gt;The study was supported by the First Candle/SIDS Alliance, CJ Martin Overseas Fellowship (National Health and Medical Research Council of Australia), CJ Murphy Foundation for Solving the Puzzle of SIDS, CJ Foundation for SIDS, National Institute of Child Health and Development, and the Developmental Disabilities Research Center at Children&apos;s Hospital Boston.&lt;/p&gt;&lt;p&gt;The researchers reported no conflicts of interest.&lt;/p&gt;&lt;p&gt;McClain provided no information on conflicts of interest.&lt;/p&gt;&lt;/div&gt;&lt;div style=&quot;clear:both;&quot;&gt;&lt;/div&gt;
    </recommendedItem>
</recommendedContent>
