Associations Between Dust Storms and Intensive Care Unit Admissions in the United States, 2000-2015

Anthropogenic climate change is influencing the incidence of dust storms and associated human exposure to coarse particulate matter (PM2.5-10) in the United States. Studies have found adverse health consequences related to dust exposure. These consequences include respiratory disease exacerbations and premature mortality, resulting in increased health care utilization. However, the impact of dust storms on critical care demand has not been studied in the United States. We seek to quantify the relationship between dust storms and surges in critical care demand by investigating the association between dust storms and intensive care unit (ICU) admissions at nearby hospitals from 2000 to 2015. ICU data were acquired from Premier, Inc. and encompass 15-20% of all ICU admissions in the United States. Dust storm, meteorology, and air pollutant data were downloaded from the U.S. National Weather Service, the U.S. National Climatic Data Center, and the U.S. Environmental Protection Agency websites, respectively. Associations between ICU admission and dust storms, controlling for temperature, dew point temperature, ambient PM2.5 and ozone, as well as seasonally varying confounders, were estimated using a distributed lag conditional Poisson model with overdispersion. We found a 4.8% (95% CI: 0.4, 9.4; p = 0.033) increase in total ICU admissions on the day of the dust storm (Lag 0) and a 9.2% (95% CI: 1.8, 17.0; p = 0.013) and 7.5% (95% CI: 0.3, 15.2; p = 0.040) increase in respiratory admissions at Lags 0 and 5. North American dust storms are associated with increases in same day and lagged demand for critical care services at nearby hospitals.

Emotional Accessibility Is More Important Than Sexual Accessibility in Evaluating Romantic Relationships - Especially for Women: A Conjoint Analysis

Prior research examining mate expulsion indicates that women are more likely to expel a mate due to deficits in emotional access while men are more likely to expel a mate due to deficits in sexual access. Prior research highlights the importance of accounting for measurement limitations (e.g., the use of incremental vs. forced-choice measures) when assessing attitudes toward sexual and emotional infidelity, Sagarin et al., 2012, Wade and Brown, 2012). The present research uses conjoint analysis, a novel methodology for controlling several limitations of using continuous self-report measures in mate expulsion research. Participants (N = 181, 128 women) recruited from Bucknell University and several psychology recruitment listservs in the United States rated nine profiles that varied in three potential levels of emotional and sexual accessibility. Men were more likely to want to break up with a partner due to sexual accessibility deficits, whereas women were more likely to want to break up due to emotional accessibility deficits. However, regardless of sex, emotional inaccessibility was more likely to produce mate expulsion. These findings are consistent with prior theory and highlight the need to disentangle emotional accessibility into its constituent in-pair benefits. This research also illustrates the utility of conjoint analysis as a statistical tool for studying how humans resolve trade-offs among competing outcomes during romantic decision-making.

Cardiovascular risk factors and anthropometric measurements of adolescent body composition: a cross-sectional analysis of the Third National Health and Nutrition Examination Survey

OBJECTIVE

To assess the association between certain cardiovascular risk factors that are commonly clustered among individuals with insulin resistance syndrome (IRS) and adolescents' body composition measurements.

METHODS

We examined a total of 1068 adolescents aged 12-16 years from the Third National Health and Nutrition Examination Survey. The sex-specific third tertiles of glucose, triglycerides, systolic blood pressure and first tertile of high-density-lipoprotein (HDL) cholesterol were used to classify the presence of each IRS component. We compared adolescents with none, one, two and three/four IRS components across a series of body composition measurements and lipid profile.

RESULTS

About 18% of the adolescents had three or four IRS components. Overall, IRS among adolescents is more likely to be associated with body weight and measurements related to body girths and less likely to be associated with the measurements related to body lengths. Multivariate analysis results showed that the odds of being at increased risk of obesity (body mass index z-score> 0.85) were significantly greater among those with two (odds ratio (OR)=4.5; 95% CI 2.5-8.2) and three/four (OR=8.9, 95% CI 4.5-17.5) IRS components compared to those without any IRS components. Across sex, the level of non-HDL cholesterol was significantly higher among adolescents with more IRS components (P for trends <0.05).

CONCLUSIONS

The clustered cardiovascular risk factors are strongly associated with an increased risk of obesity and higher levels of non-HDL cholesterol among adolescents.

Associations between water-treatment methods and diarrhoea in HIV-positive individuals

This manuscript extends our previously published work (based on data from one clinic) on the association between three drinking water-treatment modalities (boiling, filtering, and bottling) and diarrhoeal disease in HIV-positive persons by incorporating data from two additional clinics collected in the following year. We conducted a cross-sectional survey of drinking water patterns, medication usage, and episodes of diarrhoea among HIV-positive persons attending clinics associated with the San Francisco Community Consortium. We present combined results from our previously published work in one clinic (n = 226) with data from these two additional clinics (n = 458). In this combined analysis we employed logistic regression and marginal structural modelling of the data. The relative risk of diarrhoea for 'always' vs. 'never' drinking boiled water was 0.68 (95% CI 0.45-1.04) and for 'always' vs. 'never' drinking bottled water was 1.22 (95 % CI 0.82-1.82). Drinking filtered water was unrelated to diarrhoea (1.03 (95% CI 0.78, 1.35) for 'always' vs. 'never' drinking filtered water]. Adjustment for confounding did not have any notable effect on the point estimates (0.61, 1.35 and 0.98 for boiled, bottled, and filtered water respectively, as defined above). The risk of diarrhoea was lower among those consuming boiled water but this finding was not statistically significant. Because of these findings, the importance of diarrhoea in immunocompromised individuals, and the limitations of cross-sectional data further prospective investigations of water consumption and diarrhoea among HIV-positive individuals are needed.

Risk factors in HIV-associated diarrhoeal disease: the role of drinking water, medication and immune status

In a cross-sectional survey of 226 HIV-infected men, we examined the occurrence of diarrhoea and its relationship to drinking water consumption patterns, risk behaviours, immune status and medication use. Diarrhoea was reported by 47% of the respondents. Neither drinking boiled nor filtered water was significantly associated with diarrhoea (OR = 0.5 [0.2, 1.6], 1.2 [0.6, 2.5] respectively), whereas those that drank bottled water were at risk for diarrhoea (OR = 3.0 [1.1, 7.8]). Overall, 47% always or often used at least one water treatment. Of the 37% who were very concerned about drinking water, 62% had diarrhoea, 70% always or often used at least one water treatment. An increase in CD4 count was protective only for those with a low risk of diarrhoea associated with medication (OR = 0.6 [0.5, 0.9]). A 30% attributable risk to diarrhoea was estimated for those with high medication risk compared to those with low medication risk. The significant association between concern with drinking water and diarrhoea as well as between concern with drinking water and water treatment suggests awareness that drinking water is a potential transmission pathway for diarrhoeal disease. At the same time we found that a significant portion of diarrhoea was associated with other sources not related to drinking water such as medication usage.

Beyond biology: the social context of prenatal behaviour and birth outcomes

OBJECTIVES

In this study we examine the factors that are associated with adverse birth outcomes using a representative national sample. In our analysis we take into account factors which are related to the mother's behaviour during pregnancy and also consider the socio-economic circumstances of the family.

METHODS

A series of logistic regression models are used to determine the increased risks of low birth weight, preterm, and small for gestational age births associated with maternal smoking, alcohol consumption and high blood pressure in relation to socio-economic factors, such as family dysfunction, social support, income adequacy, age, and education.

RESULTS

All socio-economic factors showed gradients of maternal smoking during pregnancy while only mother's education and socio-economic status demonstrated gradients of alcohol use and high blood pressure. Maternal smoking, high blood pressure, higher levels of family dysfunction, and lower levels of mother's education were found to significantly increase the risk of an adverse birth outcome.

CONCLUSIONS

Interventions designed to mitigate the hazards of adverse birth outcomes should be designed to reflect the gradients of risky prenatal maternal behaviours associated with age, education, income, and family dysfunction.

Revisiting student self-rated physical health

There has been little research as to the development of self-rated health among adolescents. In this paper, we present a replication of a model of student self-rated health initially proposed by Vingilis, Wade and Adlaf (1998) using data from 1993 Ontario Student Drug Use Survey (n=840). The data for this replication come from the first wave of the US National Longitudinal Study of Adolescent Health (public release data, n=5673). The original model is tested by a series of nested regression equations and path analysis. The results add support for the original model and are notable given that many items used to build the underlying constructs differ across the two datasets.

Major depressive disorder and marital transition among mothers: results from a national panel study

This analysis employs a national panel study to examine the relationship between marital transition and depression among mothers within the framework of selection and causation processes. The data come from the two-wave, longitudinal National Population Health Survey (NPHS) by Statistics Canada collected in 1994 and again in 1996 focusing on women between 20 and 65 years of age with children living at home (N = 2169). Compared with mothers who remain married, mothers making the transition into single-parenthood had a significantly higher rate of major depression at Time 1, which increased, but not significantly, at Time 2. This suggests that a selection effect may explain the elevated levels of depression among mothers experiencing a marital disruption. Rates of depression among single-parent mothers making the transition into a marital relationship did not decrease significantly between waves nor did the rate differ significantly from stable single-parent mothers at Time 1 or Time 2, suggesting that movement into marriage is not a protective factor.

The relationship between physical exercise and distress in a national sample of Canadians

This paper presents an empirical examination of the relationship between physical exercise and generalized distress within a stress process framework by examining how chronic strains, self-esteem, mastery, and social support influence this relationship. The analysis employed the 1994 wave of the National Population Health Survey consisting of a sample of 12,636 Canadians between 20 and 64 years of age. Findings suggest that physical exercise is a significant predictor of generalized distress independent of chronic strain, self-esteem and social support. However, mastery mediated the association between physical exercise and distress. Moreover, mastery moderated the relationship indicating that it is a more important resource for people who are inactive.

The effect of sociodemographics, social stressors, health status and psychosocial resources on the age-depression relationship

This study examines how an extensive set of covariates identified in previous research--sociodemographics, social stressors, health status and psychosocial resources--influence the age-depression relationship. The analyses were based on data collected for the 1994 National Population Health Survey (N = 16,291) by Statistics Canada. Analyses were conducted using OLS regression for generalized distress and logistic regression for major depressive episode. The relationship between age and both outcomes was linear and negative after controlling for sociodemographics. Controlling for social stress reduced levels of depression among younger cohorts while controlling for poor health status reduced levels of depression among the elderly. Controlling for psychosocial resources generally reduced the level of depression among older cohorts, however, the results were mixed across outcomes. The inclusion of all covariates appears to negate the effects of one another in that the fully adjusted relationships between age and depression across both outcomes were not significantly different from their bivariate relationships.

The clustering of severe behavioural, health and educational deficits in Canadian children: preliminary evidence from the National Longitudinal Survey of Children and Youth

This study identifies a high-risk subpopulation of children with a markedly antisocial behavioural profile in a national sample of Canadian children. We examine a broad array of environmental and child factors that may be associated with this high-risk group. The data are for 18,135 two to eleven year olds in the National Longitudinal Survey of Children and Youth. A cluster analysis was performed to identify children possessing extreme antisocial behaviour across five dimensions: aggression, hyperactivity, prosocial behaviour, emotional difficulties and misconduct. Clusters were compared across structural, family, school, neighbourhood, and health covariates. Membership in this severe cluster is associated with material disadvantage across the range of environmental factors as well as significant deficits in child health and education.

The clustering of severe behavioural, health and educational deficits in Canadian children: preliminary evidence from the National Longitudinal Survey of Children and Youth

This study identifies a high-risk subpopulation of children with a markedly antisocial behavioural profile in a national sample of Canadian children. We examine a broad array of environmental and child factors that may be associated with this high-risk group. The data are for 18,135 two to eleven year olds in the National Longitudinal Survey of Children and Youth. A cluster analysis was performed to identify children possessing extreme antisocial behaviour across five dimensions: aggression, hyperactivity, prosocial behaviour, emotional difficulties and misconduct. Clusters were compared across structural, family, school, neighbourhood, and health covariates. Membership in this severe cluster is associated with material disadvantage across the range of environmental factors as well as significant deficits in child health and education.

Analysis of breast milk to assess exposure to chlorinated contaminants in Kazakhstan: sources of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposures in an agricultural region of southern Kazakhstan

High levels of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD; up to 208 pg/g fat) were measured in samples of breast milk collected in 1997 from 64 donors [41 first-time mothers (primiparae)] living on state farms in southern Kazakhstan. TCDD was the major contributor (70%) to the toxic equivalents, matching the congener patterns found in breast milk and serum samples collected in 1994 and 1996 from donors in nearby villages. The highest TCDD levels were found in state farms adjacent to a reservoir (zone A), which receives agricultural runoff from cotton fields. TCDD levels in zone A were significantly higher than levels in a region more distant (zone B; > 10 miles) from the reservoir (zone A: mean 53 pg/g, n = 17; zone B: mean 21 pg/g, n = 24; p = 0.0017). Levels of TCDD in breast milk and animal-derived foodstuffs were 10 times U.S. levels. Body burden and dietary data suggest that exposures to TCDD are chronic, environmental, and long term and may be related to the use of chemicals in cotton agriculture. The data suggest that the most likely source is the use of cotton defoliants contaminated with TCDD, and the most likely pathway for human exposure is via the consumption of contaminated foodstuffs.

The development of self-rated health during adolescence: an exploration of inter- and intra-cohort effects

Self-rated health is a commonly used measure of physical health status. While the development of one's perception of self-rated health likely occurs during childhood and adolescence, its development has been largely unexplored. This study addresses this issue by examining the relationship between adolescent self-rated health and personal (sex, age) and situation (family structure, family income) factors at five different time intervals to identify inter- and intra-cohort effects as well as concomitant changes in adolescent health compromising behaviour, specifically substance use. Five waves between 1989 and 1997 of the biennial Ontario Student Drug Use Survey (OSDUS) by the Addiction Research Foundation (ARF) consisting of 19,512 cases were examined. The results indicate the presence of both inter- and intra-cohort effects on self-rated health. In addition, health-compromising behaviours had a varied effect on self-rated health across grade. This analysis confirms some previous findings but also presents contradictory evidence by identifying the complexity of relationships among these factors and self-rated health.

Analysis of breast milk to assess exposure to chlorinated contaminants in Kazakstan: high levels of 2,3,7, 8-tetrachlorodibenzo-p-dioxin (TCDD) in agricultural villages of southern Kazakstan

To assess levels of chlorinated contaminants in breast milk, we measured organochlorine pesticides, polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs) in breast milk samples collected in 1994 according to the World Health Organization protocol from 92 donors that were representative of regional populations in southern Kazakstan. High levels (10-120 pg/g fat) of 2,3,7, 8-tetrachlorodibenzo-p-dioxin (TCDD), the most toxic of the PCDD/PCDF congeners, were found in breast milk samples from an agricultural region. TCDD was the major contributor (75%) to the international toxicity equivalents of these samples. The same distinctive PCDD/PCDF congener pattern was found in 15 breast milk samples and 4 serum samples collected in 1996 in a follow-up study, and has now been confirmed by three analytical laboratories.

Reducing economic disparity to achieve better health: modelling the effect of adjustments to income adequacy on self-reported morbidity among the elderly in Canada

Class differentials in health have been documented extensively in the sociological literature of the past two decades. Although sociologists have been concerned with analyzing the relationship between social class and health, less attention has been paid to modelling the effects of minimizing social disparities on health outcomes. From a sub-sample (N = 1,943) of elderly respondents aged 65 and over, four logistic regression equations where income adequacy was shown to be correlated with morbidity were selected. By adjusting the scores on the income adequacy variable, we were able to model the effect of shifting individuals from lower to higher income groups. The most dramatic results were obtained after all respondents were shifted into the highest income adequacy classification. A more realistic hypothetical model, the transfer of individuals from the lowest income group to the next category, produced the least attractive reduction in morbidity. Obviously, income adjustment alone is insufficient. Findings are discussed in terms of interventions to prevent economic disparity in old age.

Correlates of body weight in the 1994 National Population Health Survey

OBJECTIVE

This study examines three specific questions about obesity and overweight, using a nationally representative sample of Canadians. Are sociodemographic and lifestyle behaviors associated with body weight? Is body weight correlated with specific health outcomes? Has the prevalence of obesity in Canada changed since 1978?

METHODS

Secondary data analysis of a cross-sectional survey.

SAMPLE

This study uses the 1994 National Population Health Survey (NPHS) by Statistics Canada. It is a stratified random sample of 19600 Canadians across all provinces.

RESULTS

The results show that age, gender, education, birth place and region, are significantly associated with obesity. When a lower criterion is used for overweight and obesity (body mass index, BMI > or = 25), dummy variables for marital status and occupation are also significant. Second, obesity is associated with poorer self-rated health, high blood pressure, heart disease, diabetes, arthritis, respiratory and stomach problems. For those respondents who have a BMI score of 25 or greater, there is also an association with stroke. Finally, it is unclear whether the prevalence of obesity has changed. However, there appears to be a systematic difference between studies using actual height and weight measurements (anthropometric) vs self-reported measurements.

CONCLUSIONS

Weight can be considered a modifiable risk factor and reductions in the prevalence of obesity should reduce the risk of specific chronic conditions. Provincial variations in the prevalence of obesity (BMI > or = 27) and overweight and obesity (BMI > or = 25) suggest that collapsing provinces into regions may obscure important inter-provincial differences in body weight. More research is required to assess whether or not obesity is decreasing in Canada. Some of the limitations of self-reported data are discussed.

What factors predict student self-rated physical health?

Data from a randomly selected sample of 840 Ontario students were used to examine factors that affect self-rated physical health. Analyses focused on demographics, family structure, family financial situation, child-parent relationship, school achievement, self-esteem, alcohol, tobacco and cannabis use as factors which directly and indirectly influence self-rated health. Specifically, higher income, good child-parent relationship, higher interest and achievement in school, high self-esteem, not smoking, and being male were all positively and directly associated with higher self-ratings of health. Family structure was mediated by income, and school achievement and child-parent relationship were mediated by tobacco use and self-esteem. Our analyses suggest that student perceptions of physical health are affected by demographic, economic, social, psychological and competency factors.

Age and depression in a nationally representative sample of Canadians: a preliminary look at the National Population Health Survey

There are considerable inconsistencies in the literature concerning the relationship between age and depression. Recently, however, two independent studies in the U.S. have shown that the distribution is U-shaped with the lowest reported levels of depression at ages 45-49. Three reasons for past inconsistencies are identified and addressed using the 1994 National Population Health Survey by Statistics Canada. Using both a distress scale and a diagnostic measure, a substantially different relationship was found. The prevalence of distress decreased steadily with age until about 65, with only a slight increase afterwards for both males and females. After the introduction of several sociodemographic covariates, however, this relationship was clearly negative. These findings are discussed in terms of future research questions.

Age and depression in a nationally representative sample of Canadians: a preliminary look at the National Population Health Survey

There are considerable inconsistencies in the literature concerning the relationship between age and depression. Recently, however, two independent studies in the U.S. have shown that the distribution is U-shaped with the lowest reported levels of depression at ages 45-49. Three reasons for past inconsistencies are identified and addressed using the 1994 National Population Health Survey by Statistics Canada. Using both a distress scale and a diagnostic measure, a substantially different relationship was found. The prevalence of distress decreased steadily with age until about 65, with only a slight increase afterwards for both males and females. After the introduction of several sociodemographic covariates, however, this relationship was clearly negative. These findings are discussed in terms of future research questions.

Characterization of ten species of mycobacteria by reaction-gas-liquid chromatography

The methanolic tetramethylammonium hydroxide whole-cell lysates of nine species of mycobacteria and the "rhodochrous complex" were examined by gas-liquid chromatography. The gas chromatographic patterns produced 10 characteristic chromatographic groups that corresponded to the 10 species studied. The gas chromatograms of Mycobacterium tuberculosis were very easily distinguished from the other mycobacterial strains by high levels of a component that eluted much later than the other components. The remaining nine species could be distinguished on the basis of characteristic components and by different amounts of components common to more than one species. This study demonstrated that direct gas-liquid chromatographic characterization of M. tuberculosis and other myobacterial species was not only feasible but practical in the clinical laboratory.

New gas chromatographic characterization procedure: preliminary studies on some Pseudomonas species

Strains of saccharolytic and nonsaccharolytic Pseudomonas species were examined by a new single-step gas chromatographic characterization procedure. Cells were digested in a methanolic solution of tetramethylammonium hydroxide pentahydrate, and the digestates were subjected to gas-liquid chromatographic analysis. The chromatograms were examined for similarities and differences in their overall patterns. A single component was defined for use as an internal qualitative and quantitative standardizing component in order to develop relative retention time-relative peak height profiles of each organism. Comparison of these profiles enabled the characterization of strains of Pseudomonas aeruginosa, P. putida, P. cepacia, P. pseudomallei, P. stutzeri, P. pseudoalcaligenes, P. alcaligenes, P. diminuta, P. denitrificans, and P. acidovorans. The P. maltophilia and P. putrefaciens digestates showed chromatograms which were superficially similar yet easily distinguished as belonging to different species. The chromatograms of these two organisms were very different from those of other pseudomonads.