The role of farm operational and rural environments as potential risk factors for pediatric asthma in rural Saskatchewan.

BACKGROUND: Researchers have historically reported that farm children have a lower prevalence of asthma compared to more urban children. Potential explanations include theories surrounding differences in personal factors, access to health care, engagement in health risk behaviors, and differences in the environment. OBJECTIVE: The aims of this study were to: (1) confirm whether the prevalence of asthma varies between farm and small town status among children living in Saskatchewan; (2) identify risk and protective factors for asthma, and use this information to infer which of the above theories is most explanatory for any observed geographic variations in pediatric asthma. METHODS: Rural students (N = 2383, 42% participation rate) from the province of Saskatchewan participated in a 2011 cross-sectional study. Parents completed a survey that included questions about location of residence, respiratory symptoms, potential risk factors for respiratory disease, and exposures to farm activities. Multiple logistic regression was used to examine relations between respiratory outcomes (asthma, wheeze) with farm type and farm activities, while accounting for factors that may underlie such relations. RESULTS: Asthma and wheeze prevalence did not differ by residential status. Living on a grain farm (OR = 0.64, 95% CI = 0.43-0.96), cleaning or playing in pens (OR = 0.69, 95% CI = 0.46-1.02), filling grain bins (OR = 0.56, 95% CI = 0.32-0.96), and riding horses (OR = 0.65, 95% CI = 0.40-1.05) were protective factors for ever diagnosis with asthma. CONCLUSIONS: We identified a number of risk and protective factors for asthma and associated wheeze. This suggests the need to focus on specific environmental explanations to better understand previously observed associations between farm residential status and asthma.

Factors contributing to risks for pediatric asthma in rural Saskatchewan.

BACKGROUND: Rural children have lower reported rates of asthma compared with urban children. Although reasons for these differences remain unclear, 3 possible explanations exist: (1) environmental differences, (2) variations in health care access, and (3) variations in health risk behaviors. OBJECTIVE: We investigated asthma among children living on farms and in small towns and its potential determinants, including personal, behavioral, and environmental factors. METHODS: School children (n = 842, ages 6-13; participation rate = 72.0%) were involved in a 2003 cross-sectional study. Their parents completed a lung health survey that included questions about asthma, asthma-like symptoms, and potential determinants of asthma (demographic, environmental, health risk behaviors). Participating children were classified into farm dwellers (live on farm or acreage) and small town dwellers. Multiple logistic regression was used to investigate the association between asthma and wheeze with demographic, environmental, and behavioral exposures with simultaneous adjustment for confounders. RESULTS: Asthma and wheeze prevalence was not significantly different between farm and small town areas (current asthma: 16% vs 13%, respectively; current wheeze: 27% vs 21%, respectively) and followed consistent patterns. Factors associated with diagnosed asthma were dampness (odds ratio [OR] = 1.85; 95% confidence interval [CI] = 1.08-3.17), with enrollment in daycare found to be protective (OR = 0.53; 95% CI = 0.33-0.85). Being obese or overweight was associated with wheeze (OR = 1.77; 95% CI = 1.06-2.97). CONCLUSION: Given the differences between areas and the associations between environmental risk factors and obesity with asthma and wheeze, the study findings support environment and health risk behavior explanations for the observed geographic variations.

Probabilistic classification and gambling in patients with schizophrenia receiving medication: comparison of risperidone, olanzapine, clozapine and typical antipsychotics.

RATIONALE: We have previously shown that patients with schizophrenia treated with typical antipsychotics were impaired on the weather prediction probabilistic classification learning (PCL) task that relies on striatal function, and that similar patients treated with atypical antipsychotics were impaired on the Iowa gambling task (IGT) that depends on medial prefrontocortical function. OBJECTIVES: We tested the hypothesis that test performance of patients treated with risperidone will be more similar to those treated with typical rather than atypical antipsychotics. RESULTS: Groups of schizophrenia patients treated with risperidone, olanzapine, clozapine or typical antipsychotics did not differ on the Positive and Negative Syndrome Scale or the Mini Mental State Exam (MMSE) but scored lower than controls on the MMSE. For the PCL task, patients treated with clozapine improved over trials while those treated with typical antipsychotics, olanzapine, or risperidone did not. For the IGT, patients treated with typical antipsychotics or risperidone improved over trials while those treated with clozapine or olanzapine did not. CONCLUSIONS: Results generally supported the hypothesis that patients treated with risperidone perform more like those treated with typical antipsychotics than those treated with other atypical antipsychotics.