Exposure to the carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) in smokers from 3 populations with different risks of lung cancer.

Native Hawaiian smokers are at higher risk and Japanese-American smokers at lower risk of lung cancer (LC), compared with white smokers, even after accounting for smoking history. Because variation in carcinogen exposure/metabolism may occur separately of smoking amount, we compared urinary biomarkers of uptake and detoxification of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-a potent lung carcinogen-among 578 smokers in these ethnic/racial groups in Hawaii. We measured the NNK metabolite 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) and its glucuronide (NNAL-Gluc) and examined total NNAL (NNAL + NNAL-Gluc) and the NNAL detoxification ratio (NNAL-Gluc:NNAL). Native Hawaiians and Japanese-Americans had lower age- and sex-adjusted mean total NNAL, compared with whites. When further adjusting for urinary nicotine equivalents (the sum of nicotine, cotinine, trans-3'-hydroxycotinine and their respective glucuronides), only the difference between Japanese-Americans and whites was eliminated. Therefore, consistent with their lower LC risk, a lower cigarette smoke exposure explains the lower NNK dose of Japanese-Americans, but it does not explain that of Native Hawaiians. The mean detoxification ratio was also lower in Native Hawaiians and Japanese-Americans, compared with whites, even after adjusting for nicotine equivalents (p < 0.0001). Lower NNAL glucuronidation in Native Hawaiians might contribute to their increased LC risk; however, this is inconsistent with the low glucuronidation ratio similarly observed in the low-risk Japanese-American group and because Native Hawaiians had lower total NNAL levels. Thus, exposure and detoxification of NNK are unlikely to explain, by themselves, the differences in LC risk among the 3 populations studied.

Nicotine metabolism in three ethnic/racial groups with different risks of lung cancer.

Previously, we documented that smoking-associated lung cancer risk is greater in Hawaiians and lower in Japanese compared with Whites. Nicotine metabolism by cytochrome P450 2A6 (CYP2A6) varies across ethnicity/race and is hypothesized to affect smoking behavior. We investigated whether higher CYP2A6 activity results in the smoker extracting more nicotine (adjusting for cigarettes per day) and being exposed to higher levels of tobacco-specific nitrosamine [4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)] and pyrene, a representative polycyclic aromatic hydrocarbon. We conducted a cross-sectional study of 585 smokers among the three main ethnic/racial groups in Hawaii and examined whether differences in CYP2A6 activity correlate with the ethnic/racial differences in lung cancer risk. We assessed CYP2A6 activity by nicotine metabolite ratio (total trans-3-hydroxycotinine/total cotinine) and caffeine metabolite ratio (1,7-dimethyl uric acid/1,7-dimethylxanthine) in 12 h urine. We also measured urinary nicotine equivalents (sum of nicotine, cotinine, and trans-3-hydroxycotinine and their respective glucuronides), a marker of nicotine dose, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol and its glucuronide, markers of NNK exposure, and 1-hydroxypyrene, a marker of pyrene exposure. The nicotine metabolite ratio was higher in Whites than in Japanese and intermediate in Hawaiians (P values < 0.05). Cigarettes per day-adjusted nicotine equivalents were lower in Japanese compared with Hawaiians or Whites (P = 0.005 and P < 0.0001, respectively) and greater in men than women (P < 0.0001). Nicotine equivalents and total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol increased with CYP2A6 activity, indicating that smokers with greater nicotine metabolism smoke more extensively and have a higher internal NNK dose. The particularly low nicotine metabolism of Japanese smokers may contribute to their previously described decreased lung cancer risk.

Hospitalizations and deaths caused by diarrhea in children five years old and younger at four hospitals in Haiti, 2010-2012.

Worldwide, diarrhea is a major contributor to morbidity and mortality in children; however, there are few data on the burden of diarrheal disease in Haiti. We conducted a retrospective review of hospital discharge registries from 2010 to 2012 in the pediatric wards of four Haitian hospitals and recorded the number of all-cause hospitalizations and deaths as well as diarrheal hospitalizations and deaths by age (≤ 2 and 3-5 years) and epidemiological week. Diarrhea was associated with 3,582 (33.7%) of 10,621 hospitalizations and 62 (11.5%) of 540 in-hospital deaths in children ≤ 5 years old. Of these children, 88.5% and 96.8%, respectively, were among children ≤ 2 years old. The highest proportions of diarrhea-associated hospitalizations occurred from January to April. At four Haitian hospitals over a 3-year period, during which time a major epidemic of cholera occurred, diarrheal disease in children ≤ 5 years was a major contributor to pediatric hospitalizations and mortality.

A proposed model curriculum in global child health for pediatric residents.

OBJECTIVE: In response to the increasing engagement in global health (GH) among pediatric residents and faculty, academic GH training opportunities are growing rapidly in scale and number. However, consensus to guide residency programs regarding best practice guidelines or model curricula has not been established. We aimed to highlight critical components of well-established GH tracks and develop a model curriculum in GH for pediatric residency programs. METHODS: We identified 43 existing formal GH curricula offered by U.S. pediatric residency programs in April 2011 and selected 8 programs with GH tracks on the basis of our inclusion criteria. A working group composed of the directors of these GH tracks, medical educators, and trainees and faculty with GH experience collaborated to develop a consensus model curriculum, which included GH core topics, learning modalities, and approaches to evaluation within the framework of the competencies for residency education outlined by the Accreditation Council for Graduate Medical Education. RESULTS: Common curricular components among the identified GH tracks included didactics in various topics of global child health, domestic and international field experiences, completion of a scholarly project, and mentorship. The proposed model curriculum identifies strengths of established pediatric GH tracks and uses competency-based learning objectives. CONCLUSIONS: This proposed pediatric GH curriculum based on lessons learned by directors of established GH residency tracks will support residency programs in creating and sustaining successful programs in GH education. The curriculum can be adapted to fit the needs of various programs, depending on their resources and focus areas. Evaluation outcomes need to be standardized so that the impact of this curriculum can be effectively measured.

Two cases of restavek-related illness: clinical implications of foster neglect in Haiti.

Restaveks, or indentured foster children, are a poorly understood, vulnerable subclass of Haitian society. From 2001 to the present, a partnership between multiple US academic medical centers and Project Medishare for Haiti has held an ongoing series of mobile clinics in rural Haiti. Multiple cases of restavek-related illness were identified. At a recent pair of mobile clinics, the authors identified two restavek cases that were significantly worse off than their communal peer groups and required immediate care. Given the lack of a robust legal support to protect orphaned children in Haiti, clinicians have an important role in advocating for restaveks at the bedside. The plight of Haiti's restaveks is widely reported in the human rights literature but is not publicly recognized as an issue for community health and wellbeing among physicians. To address these health disparities, the health consequences of an entire class of neglected children must be further explored.

Smokers with the CHRNA lung cancer-associated variants are exposed to higher levels of nicotine equivalents and a carcinogenic tobacco-specific nitrosamine.

A locus at 15q24/15q25.1, which includes the nicotinic acetylcholine receptor A subunits 3 and 5 (CHRNA3 and CHRNA5) genes, has recently been associated with lung cancer risk, self-reported number of cigarettes smoked per day, and a nicotine dependence scale. It is not clear whether the association with lung cancer is direct or mediated through differences in smoking behavior. We used urinary biomarkers to test whether two linked lung cancer risk variants in CHRNA3 (rs1051730) and CHRNA5 (rs16969968) are associated with intensity of smoking and exposure to a tobacco-specific carcinogenic nitrosamine per cigarette dose. We studied 819 smokers and found that carriers of these variants extract a greater amount of nicotine (P = 0.003) and are exposed to a higher internal dose of 4-(methylnitrosamino)-I-(3-pyridyl)-1-butanone (P = 0.03) per cigarette than noncarriers. Thus, smokers who carry the CHRNA3 and CHRNA5 variants are expected to be at increased risk for lung cancer compared with smokers who do not carry these alleles even if they smoked the same number of cigarettes. Number of cigarettes per day, even if it could be accurately assessed, is not an adequate measure of smoking dose.