In treating malaria in schoolchildren in Africa, the use of intermittent preventive treatment (IPT) not only lowers the prevalence of anemia but also improves attention span in the children. These conclusions, published in an Article released on July 11, 2008 in The Lancet, could help guide future interventions in this and similar settings. Malaria, a major cause of death and disease around the world often affects children, but its consequences on health and education during the school age years is poorly understood. Historically, standard treatments and chemical prevention methods have been effective, and are associated with lower rates of malarial parasite infection, severe anemia (a major symptom of malaria) and malaria related deaths. This results in reduced school absenteeism. Though these therapies and methods might largely be effective, they may be too expensive to effectively implement in sub-Saharan Africa. Additionally, subclinical infections are common in the population, making directed therapies difficult. An alternative therapy, intermittent preventive treatment involves mass distribution of a full course of anti-malarial treatment, regardless of the infection status of each individual. To investigate the effects of IPT on the biological and educational effects of malaria, Dr. Sian Clarke, London School of Hygiene and Tropical Medicine (LSHTM), UK, and colleagues performed a randomized controlled trial on children between the ages of 5 and 18 years from 30 primary schools in an area of Western Kenya with high malaria transmission rates. IPT was administered to 2,604 children, composed of three treatments of sulfadoxine-pyrimethamine in combination with amodiaquine at four month intervals. Meanwhile, a group of 2,302 students received a placebo. The children were evaluated for anemia, defined as a hemoglobin concentration below 110g/L. A reduction in malaria occurrence was associated with IPT after 12 months. That is, prevalence of parasite presence was <5% in the IPT group in comparison with 39.7% in the placebo group. Additionally, anemia levels decreased, and the prevalence of anemia was 6.3% in the IPT group in comparison with 12.6% in the placebo group. Finally, in classroom-based tests of sustained attention, IPT group participants showed significant improvement in comparison with students in the placebo group. This effect, however, showed no effect on educational achievement or hyperactive-compulsive behaviors. The authors conclude with a statement about the potential benefits of this new treatment if used in new policy in these areas. "The pronounced effects of the IPT intervention on anemia and malaria parasitemia, and the effect on sustained attention, highlight the issue of the continued, and often unrecognized, malaria burden among school-aged children in Africa and the potential of school-based programs for tackling the problem. Our findings also illustrate the possible gains of integrating malaria control into broader school health programs." View Source
A new study published in the Annals of the Rheumatic Diseases finds that compared to females born with average birth weight, those born with heavy birth weight are two times as likely to develop rheumatoid arthritis when they become adults. Rheumatoid arthritis is a condition that occurs when the immune system attacks the joints, lungs or skin and results in inflammation, pain, and loss of functioning mobility. Researcher L. A. Mandl (Division of Rheumatology, Hospital for Special Surgery, Weill Cornell Medical College) and colleagues argue that these findings support the fetal origin of disease theory. That is, factors that occur during pregnancy program an individual to be more prone to certain diseases and conditions in adult life. For example, previous research has linked low birth weight to conditions such as diabetes, coronary heart disease, and high blood pressure, and high birth weight has been associated with an increased risk of breast cancer and leukemia. These new findings on rheumatoid arthritis development come from a survey of more than 87,000 women, age 30 to 55, who took part in the US Nurses' Health Study from 1976 and 2002. In two year intervals, the women responded to questions about their health, lifestyle, and family illness. In 1992, researchers asked them questions about birth weight. Between 1976 and 2002, 619 women received their first diagnosis of rheumatoid arthritis. The average birth weight was between 3.2 to 3.85 kg, and women who weighed over 4.45 kg at birth were found to be twice as likely to develop the autoimmune disease known as rheumatoid arthritis. These findings held after the researchers statistically controlled for factors that may influence birth weight such as socioeconomic status, parental smoking, maternal diabetes, age at first period, use of oral contraceptives or hormone replacement therapy, breastfeeding and weight. Though the authors do not have a clear biological explanation for their results, they do note that abnormal hormone regulation - a process thought to affect a baby while in the womb - is prevalent in adults with rheumatoid arthritis. The authors conclude that: "The biology underlying this association is speculative, and the relative importance of fetal nutrition versus genotype is unknown. However, if fetal nutrition has an impact on future risk of RA [rheumatoid arthritis], this could be a potentially modifiable risk factor. Further study of our observation that high birth weight is associated with an increased risk of RA could provide insight into the pathogenesis of RA. These data also provide further evidence for the importance of fetal environment as a crucible for future adult diseases." View Source
A previously healthy man died after inhaling fungal spores from dead plant material while gardening in May 2007, and is discussed in a Case Report released on June 13, 2008 in The Lancet. The man, 47 years old, was considered in good health, though he was a professional welder and smoked approximately ten cigarettes per day. He was admitted after one week presenting a sputum-producing cough, chest pain, and worsening shortness of breath. Running a fever of 100.4°F (38°C,) he had a low lymphocyte and neutrophil count. He also had coarse crackles in his lungs, and his chest radiography showed irregular nodules. Assumed to have community-acquired pneumonia, he was treated with intravenous co-amoxiclav and clarithromycin, but when his symptoms worsened, a third antibiotic, flucloxacillin, was administered. In the next day, he became so short of breath that even with supplementary oxygen he needed to be transferred to the intensive care unit (ICU.) In the ICU, it became clear from blood gas measurements that despite intubation and ventilation, adequate gas exchange was not being provided in his tissues. Additionally, he showed signs of serious sepsis. At this point, an HIV test was negative. However, two sputum samples cultured the fungus Asperillus fumigatus. According to the authors, "On closer questioning, the patient's partner revealed that his symptoms had started less than 24h after he had dispersed rotting tree and plant mulch in the garden, where clouds of dust had engulfed him." Treatment with intravenous liposomal amphotericin B was started. The man was subsequently transferred to another unit for extracorporeal membrane oxygenation (ECMO,) which is similar to being supported by a heart-lung machine. Upon his arrival, despite the ECMO treatment, his blood pressure remained too low and he developed kidney failure. Although a continuous dialysis was initiated, as his condition worsened, escalation of treatment was considered inappropriate. After 72 hours, ECMO was terminated and he died soon after. The diagnosis of aspergillosis was confirmed through a laboratory analysis of blood samples. Spores of aspergillus are often found on decaying plant matter, and inhalation of these spores can cause several different types of aspergillosis. These can range from acute and invasive, like in the aforementioned patient, to chronic and necrotizing. The authors conclude with a statement regarding how this patient was an unusual example of aspergillosis, and that his case may have been influenced by immunosuppression. "Unlike most patients with acute, invasive, aspergillosis, our patient did not seem to be immunosuppressed; however, smoking and welding could have damaged his lungs, increasing his vulnerability. Since he died so quickly, we cannot exclude the possibility that he had an undetected immunodeficiency. Acute aspergillosis after contact with decayed plant matter is rare, but may be considered an occupational hazard for gardeners," they say. Additionally, they add, immediate antifungal treatment is essential in these cases: "Although liposomal amphotericin B has been used in such cases, and was the recommended treatment of choice within our hospital trust at the time of this case, more recent guidelines suggest voriconazole may currently be the optimum empirical therapy." See Full Article
A Seminar released on June 13, 2008 in The Lancet discusses nicotine addiction, and the potential for reducing its disease burden and death toll by improving public knowledge and using treatments individual to patients. This includes the potential creation of an antinicotine vaccine. Nicotine is a stimulant classically found in tobacco, and its chronic addiction is primary cause of habitual smoking. According to the seminar, there are approximately 1.2 billion smokers and approximately half of them will die from diseases directly caused by smoking. Currently, about five million smokers die each year, and if present trends continue this could increase to ten million each year by 2025. More of these smokers are men than women, necessitating separate studies by gender. For instance, of the world's male population, 92% of them live in countries where more than 25% of all males smoke. In contrast, in the world's female population, 10% live in countries where female smoking frequency is above 24%. In the United Kingdom and the United States, between 25-35% of all males smoke. In the female population, however, there is some discrepancy, as in the USA 14-24% of women smoke but more than 24% smoke in the UK. The distribution of smokers varies by country, ranging from as little to 5% of the population to over 55%. Some countries where male smoking prevalence is above 55% include Russia and Kenya. The female smoking frequencies are above 24% in Brazil, Germany, Spain, and the UK. Terminating an addiction to smoking is often recognized as a significant challenge. In the USA, over 70% of the smoking population want to quit every year and 45% attempt it. However, less than 5% of the general population is successful in this endeavor. Even simple advice from a health care professional can help improve these rates. Following guidelines set forward recently in the US, the Seminar first examines the role of counseling in quitting smoking, addressing topics including problem solving, coping, and motivational skills. According to the Seminar, this rate of termination can be enhanced by treatment for nicotine addiction itself. "Pharmacotherapies for nicotine dependence can enhance quit rates by about two-three fold," state the authors. They discuss and evaluate a number of nicotine-replacement therapies (NRTs) such as patches or nicotine gum, non-nicotine products based on efficacy, side effects, and precautions for each. Additionally, they examine improved rates of success with combinations of the nicotine patch and other products such as nicotine gum. The authors of the Seminar examine not just the characteristics of termination, but also the limited benefits of cigarette reduction, which is also achieved with higher frequency with the use of NRTs. They say, however, that these effects are counteracted by changes in the habits of the smokers: "Smokers engage in substantial compensatory smoking - deeper inhalation per cigarette - so that a reduction of cigarette consumption of 50% or more results only in a 30% decrease in biomarkers for toxicant exposure." Cigarette reduction's primary benefit, therefore, may be that it acts as an intermediate step towards quitting. There are some new treatments in development. One example is a nicotine vaccine which prompts the body's immune system to develop antibodies against the substance, and for which preliminary trials are in progress. Another is the drug rimonabant, which selectively blocks a specific cannabinoid receptor, for which large, randomized trials are being performed. Finally, pharmacogenetics, a field in which treatment is matched to the patient based on his genetic profile, is examined. The authors conclude with comments about nicotine addiction: "Nicotine or tobacco addiction should be treated as a chronic disorder. Treatment can need persistent efforts to try to assist tobacco users in their attempts at quitting. Relapse should be seen as a probable event... Treatment can improve these outcomes... The most crucial component of care is the actual delivery of such treatments." Dr. Kenneth Warner of School of Public Health, Ann Arbor, MI, USA, and Dr. Judith Longstaff Mackay, Bloomberg Initiative to Reduce Tobacco Use, Hong Kong, China, contributed an accompanying Comment in which they state the importance of The Framework Convention on Tobacco Control (FCTC,) which has presently been ratified by 154 countries. They indicate that the medical community should make a higher priority of treatment of tobacco dependence, especially in every day practice, and that they should lobby governments, who may have conflicts of interest due to tobacco lobbies, to put this legislation into effect. "Here is something simple, achievable, and unequivocally good that would relieve the suffering of literally millions of human beings," they say. See Full Article
A paper published in The Lancet Oncology has concluded that women smokers are not at a greater risk of developing lung cancer than male smokers. However, among those who have never smoked, women appear to be more likely to develop the disease than men. In the United States, the medical and health community mostly agrees that cigarette smoking is responsible for about 90% of lung cancers. One point of contention among researchers and scientists, however, deals with how cigarette smoking affects men and women differently. Existing research has not been able to provide conclusive evidence that smoking makes women more or less susceptible to lung cancer than men. Further investigating this issue, Neal Freedman (National Cancer Institute, Rockville, MD, USA) and colleagues studied a data set of almost 500,000 American men and women that contained information on smoking habits, diet, physical exercise, and incidence of lung cancer. Regarding smoking, the 279,214 men and 184,623 women (all 50 to 71 years old) were asked if they currently smoked, if they had ever smoked, and how many cigarettes per day they had smoked. Key results from the study include: * Lung cancer incidence rates were 1.47% for men and 1.21% for women. * Compared to men who never smoked, women who had never smoked were still 1.3 times more likely to develop lung cancer. * The correlation between smoking and cancer risk was strong in both men and women. * Smoking two packs of cigarettes per day makes you 50 times more likely to develop lung cancer than never smoking at all. * Compared to male smokers, women smokers were only slightly less likely (0.9 times) to develop lung cancer. Lung cancer comes in several different forms. Rates of small cell, squamous, and undifferentiated tumors were about the same for both men and women who had never smoked. Adenocarcinomas, however, were more common in women than in men. Male smokers were twice as likely as female smokers to develop squamous tumors and about as likely as female smokers to develop the other tumors. "Our findings suggest that women are not more susceptible than men to the carcinogenic effects of cigarette smoking in the lung. Vigorous efforts should continue to be directed at eliminating smoking in both sexes," conclude the authors. See Full Article
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