Donald Harrington

Maternal PUFA Status but Not Prenatal Methylmercury Exposure Is Associated with Children’s Language Functions at Age Five Years in the Seychelles

Evidence from the Seychelles Child Development Nutrition Study suggests that maternal nutritional status can modulate the relationship between prenatal methylmercury (MeHg) exposure and developmental outcomes in children. The aim of this study was to investigate whether maternal PUFA status was a confounding factor in any possible associations between prenatal MeHg exposure and developmental outcomes at 5 y of age in the Republic of Seychelles. Maternal status of (n-3) and (n-6) PUFA were measured in serum collected at 28 wk gestation and delivery. Prenatal MeHg exposure was determined in maternal hair collected at delivery. At 5 y of age, the children completed a comprehensive range of sensitive developmental assessments. Complete data from 225 mothers and their children were available for analysis. Multiple linear regression analyses revealed Preschool Language Scale scores of the children improved with increasing maternal serum DHA [22:6(n-3)] concentrations and decreased with increasing arachidonic acid [20:4(n-6)] concentrations, albeit verbal intelligence improved with increasing (n-6) PUFA concentrations in maternal serum. There were no adverse associations between MeHg exposure and developmental outcomes. These findings suggest that higher fish consumption, resulting in higher maternal (n-3) PUFA status, during pregnancy is associated with beneficial developmental effects rather than detrimental effects resulting from the higher concomitant exposures of the fetus to MeHg. The association of maternal (n-3) PUFA status with improved child language development may partially explain the authors previous finding of improving language scores, as prenatal MeHg exposure increased in an earlier mother-child cohort in the Seychelles where maternal PUFA status was not measured.

Prenatal exposure to methyl mercury from fish consumption and polyunsaturated fatty acids: associations with child development at 20 mo of age in an observational study in the Republic of Seychelles

BACKGROUNDnFish is a rich source of n-3 polyunsaturated fatty acids (PUFAs) but also contains the neurotoxicant methyl mercury (MeHg). PUFAs may modify the relation between prenatal MeHg exposure and child development either directly by enhancing neurodevelopment or indirectly through the inflammatory milieu.nnnOBJECTIVEnThe objective was to investigate the associations of prenatal MeHg exposure and maternal PUFA status with child development at 20 mo of age.nnnDESIGNnThe Seychelles Child Development Study Nutrition Cohort 2 is an observational study in the Republic of Seychelles, a high-fish-eating population. Mothers were enrolled during pregnancy and their children evaluated at 20 mo of age by using the Bayley Scales of Infant Development II (BSID-II), the MacArthur Bates Communicative Development Inventories (CDI), and the Infant Behavior Questionnaire-Revised. There were 1265 mother-child pairs with complete data.nnnRESULTSnPrenatal MeHg exposure had no direct associations with neurodevelopmental outcomes. Significant interactions were found between MeHg and PUFAs on the Psychomotor Developmental Index (PDI) of the BSID-II. Increasing MeHg was associated with lower PDI but only in children of mothers with higher n-6/n-3. Among mothers with higher n-3 PUFAs, increasing MeHg was associated with improved PDI. Higher maternal docosahexaenoic acid (DHA) was associated with improved CDI total gestures (language development) but was significantly adversely associated with the Mental Development Index (MDI), both with and without MeHg adjustment. Higher n-6:n-3 ratios were associated with poorer scores on all 3 CDI outcomes.nnnCONCLUSIONSnWe found no overall adverse association between prenatal MeHg exposure and neurodevelopmental outcomes. However, maternal PUFA status as a putative marker of the inflammatory milieu appeared to modify the associations of prenatal MeHg exposure with the PDI. Increasing DHA status was positively associated with language development yet negatively associated with the MDI. These findings may indicate the existence of an optimal DHA balance with respect to arachidonic acid for different aspects of neurodevelopment.

Combined use of heat and oxidants for controlling adult zebra mussels

Abstract The results of an experimental study are presented that demonstrate the use of chlorine or ozone to control zebra mussels at temperatures from 30 to 36°C. Control studies were conducted with no oxidant present. Three acclimation temperature ranges were tested: 0–5, 10–15, and 20–25°C. Chlorine was tested at 0.1 and 0.5 mg/L; ozone at 0.5 mg/L. Mortality was described by a cumulative normal distribution, from which times to 95% mortality were estimated and used as a dependent variable for hypothesis testing. Study results showed that the addition of chlorine or ozone was more effective than heat alone at test temperatures above 30°C. Compared to heat alone, the combined use of heat and oxidants decreased the time to 95% mortality by more than 95% at 30°C. Above 30°C, the benefits of the combined treatment strategy decreased with increasing test temperature. At 36°C, the benefits of the combined treatment strategy over heat alone were minimal. Acclimation temperature was important only for heat alone and for mussels acclimated at 0–5°C. The addition of chlorine or ozone at elevated temperatures can reduce mortality times by as much as three orders of magnitude compared to oxidant addition at ambient temperatures. The results of the study should be of significance to power plants or industries where excess heat is available to raise water temperatures.

Neurodevelopmental outcomes at 5 years in children exposed prenatally to maternal dental amalgam: the Seychelles Child Development Nutrition Study.

Limited human data are available to assess the association between prenatal mercury vapor (Hg⁰)) exposure from maternal dental amalgam restorations and neurodevelopment of children. We evaluated the association between maternal dental amalgam status during gestation and childrens neurodevelopmental outcomes at 5 years in the Seychelles Child Development Nutrition Study (SCDNS). Maternal amalgam status was determined prospectively in a longitudinal cohort study examining the associations of prenatal exposure to nutrients and methylmercury (MeHg) with neurodevelopment. A total of 236 mother-child pairs initially enrolled in the SCDNS in 2001 were eligible to participate. Maternal amalgam status was measured as number of amalgam surfaces (the primary metric) and number of occlusal points. The neurodevelopmental assessment battery was comprised of age-appropriate tests of cognitive, language, and perceptual functions, and scholastic achievement. Linear regression analysis controlled for MeHg exposure, maternal fatty acid status, and other covariates relevant to child development. Maternal amalgam status evaluation yielded an average of 7.0 surfaces (range 0-28) and 11.0 occlusal points (range 0-40) during pregnancy. Neither the number of maternal amalgam surfaces nor occlusal points were associated with any outcome. Our findings do not provide evidence to support a relationship between prenatal exposure to Hg⁰ from maternal dental amalgam and neurodevelopmental outcomes in children at 5 years of age.

Methyl mercury exposure and neurodevelopmental outcomes in the Seychelles Child Development Study Main cohort at age 22 and 24years.

BACKGROUNDnAll fish contain methyl mercury (MeHg), a known neurotoxicant at adequate dosage. There is still substantial scientific uncertainty about the consequences, if any, of mothers consuming fish with naturally-acquired levels of MeHg contamination. In 1989-1990, we recruited the Main Cohort of the Seychelles Child Development Study to assess the potential developmental effects of prenatal MeHg exposure. We report here on associations with neurodevelopmental outcomes obtained at 22 and 24years of age.nnnMETHODSnNeurodevelopmental tests at 22years included the Boston Naming Test, Cambridge Neuropsychological Test Automated Battery (CANTAB), and the Profile of Mood States. At 24years, we administered the Stroop Word-Color Test, the Barkley Adult ADHD Rating Scale, the Test of Variables of Attention, and the Finger Tapping test. We also administered a healthy behaviors survey at both ages. Primary analyses examined covariate-adjusted associations in multiple linear regression models with prenatal MeHg exposure. In secondary analyses we also examined associations with recent postnatal MeHg exposure.nnnRESULTSnWe did not observe adverse associations between prenatal MeHg exposure and any of the measured endpoints. Some measures of attention, executive function, and delayed recall showed improved performance with increasing exposure. Secondary analysis did not show consistent patterns of association with postnatal exposure.nnnCONCLUSIONSnOur cohort has been examined at ten different ages over 24years of follow-up. Findings suggest that prenatal and recent postnatal MeHg exposure from ocean fish consumption is not adversely associated with neurobehavioral development at levels that are about ten times higher than typical U.S. exposures.

Prenatal exposure to methylmercury and LCPUFA in relation to birth weight

BACKGROUNDnEpidemiologic studies have been inconclusive regarding the impact of coexposure to long chain polyunsaturated fatty acids (LCPUFA) and methylmercury (MeHg) from fish consumption during pregnancy on measures of fetal development.nnnOBJECTIVESnWe evaluated the association between birth weight and prenatal maternal LCPUFA status and MeHg exposure in the Republic of Seychelles.nnnMETHODSnWe measured LCPUFA in maternal whole blood collected at 28xa0weeks of gestation and following delivery and MeHg in maternal hair obtained at delivery. There were 230 births with complete data on birth weight and covariates. Multiple linear regression models controlled for infant sex, gestational age, maternal age, smoking during pregnancy, intrapartum weight gain, prepregnancy body mass index, maternal socioeconomic status, parity, gestational diabetes, and alcohol use during pregnancy.nnnRESULTSnThe average birth weight was 3252xa0g (range 1654-4450) and the average gestational age was 39xa0weeks (range 34-41). Prenatal MeHg exposure and maternal LCPUFA status were not associated with birth weight. Infant sex and length of gestation were the only predictors, with male sex and increased gestational age consistently associated with greater birth weight.nnnCONCLUSIONSnThese findings do not support a relationship between prenatal exposure to LCPUFA and/or MeHg from fish consumption and birth weight.

Cognitive factors predict medication adherence and asthma control in urban adolescents with asthma

Purpose Adolescents with asthma often report poor medication adherence and asthma control. Cognitive factors embedded in the social cognitive theory including self-efficacy, outcome expectations, and barrier perceptions may explain poor asthma outcomes in this population. This study was performed to examine the extent to which these cognitive factors are intercorrelated and explain medication adherence and asthma control in urban adolescents. Patients and methods A total of 373 urban adolescents (12–20 years) with asthma completed questionnaires measuring asthma-related self-efficacy, outcome expectations, barrier perceptions, medication adherence, and asthma control. Multiple linear regression was conducted to examine the extent to which the three cognitive factors predicted medication adherence and asthma control after controlling for covariates including age, sex, household income, and age at diagnosis. Results Participants’ ages were on average 14.68 (±1.94) years; 50% were female, and most (78.6%) were African American. Higher self-efficacy associated with lower barrier perceptions and higher outcome expectations (r=0.50, p<0.001; r=−0.26, p<0.001, respectively). Self-efficacy predicted better asthma control (B=−0.098, p=0.004) and adherence (B=0.426, p=0.011), whereas barrier perceptions predicted poorer asthma control (B=0.13, p<0.001) and adherence (B=−0.568, p<0.001). Self-efficacy independently predicted fewer missed doses (B=−0.621, p=0.006), and barrier perception independently predicted asthma control (B=0.12, p<0.001) and adherence (B=−0.519, p<0.001). Conclusion Improving medication adherence and asthma control among adolescents may require a multifaceted approach. Interventions focused on increasing self-efficacy and addressing barriers, actual or potential, to medication adherence could ameliorate asthma disparities in urban adolescents.

Readmission Patterns During Long-Term Follow-Up After Left Ventricular Assist Device Implantation

As more patients are supported for longer periods by a left ventricular assist device (LVAD), hospital readmission is becoming a growing problem. However, data about temporal changes in readmission rates and causes for patients with prolonged LVAD support are limited. We aimed to evaluate rates, causes, and predictors of any and long-term readmission after LVAD placement at our institution. We followed 177 HeartMate II LVAD patients for a mean of 1.90 ± 1.33 years post initial discharge after implantation. A marginal rate model was used to evaluate readmission rates, accounting for mortality. During the first year, the readmission rate was 1.79 (95% confidence interval 1.51 to 2.10) readmissions per year. The readmission rate was 1.54 (95% confidence interval 1.07 to 1.93) 2 to 3 years after initial discharge. There was a further decrease in readmission rate in the 3- to 4-year interval. The most common causes of readmission during the first year and even after 3 to 4 years of LVAD support were bleeding (excluding intracranial bleeding) and infection. Female gender was associated with an increased risk of readmission in multivariable analyses, while blood urea nitrogen was predictive of long-term readmissions. In conclusion, readmission after LVAD implantation is common, but readmission rates decrease during long-term follow-up. Bleeding and infection remain leading causes of readmission during longer follow-up and strategies to decrease these complications may reduce readmission rates. Female patients and patients with renal dysfunction have increased risk of readmission and further studies are needed to improve outcomes in these groups.

A Randomized Controlled Trial of the Rochester Forensic Assertive Community Treatment Model

OBJECTIVEnForensic assertive community treatment (FACT) is an adaptation of the assertive community treatment model and is designed to serve justice-involved adults with serious mental illness. This study compared the effectiveness of a standardized FACT model and enhanced treatment as usual in reducing jail and hospital use and in promoting engagement in outpatient mental health services.nnnMETHODSnSeventy adults with psychotic disorders who were arrested for misdemeanor crimes and who were eligible for conditional discharge were recruited from the Monroe County, New York, court system. Participants were randomly assigned to receive either FACT (N=35) or enhanced treatment as usual (N=35) for one year. Criminal justice and mental health service utilization outcomes were measured by using state and county databases.nnnRESULTSnForty-nine participants (70%) completed the full one-year intervention period. Nineteen (27%) were removed early by judicial order, one was removed by county health authorities, and one died of a medical illness. Intent-to-treat analysis for all 70 participants showed that those receiving the FACT intervention had fewer mean±SD convictions (.4±.7 versus .9±1.3, p=.023), fewer mean days in jail (21.5±25.9 versus 43.5±59.2, p=.025), fewer mean days in the hospital (4.4±15.1 versus 23.8±64.2, p=.025), and more mean days in outpatient mental health treatment (305.5±92.1 versus 169.4±139.6, p<.001) compared with participants who received treatment as usual.nnnCONCLUSIONSnThe Rochester FACT model was associated with fewer convictions for new crimes, less time in jail and hospitals, and more time in outpatient treatment among justice-involved adults with psychotic disorders compared with treatment as usual.