Polytomous regression did not outperform dichotomous logistic regression in diagnosing serious bacterial infections in febrile children

OBJECTIVE: To compare polytomous and dichotomous logistic regression analyses in diagnosing serious bacterial infections (SBIs) in children with fever without apparent source (FWS). STUDY DESIGN AND SETTING: We analyzed data of 595 children aged 1-36 months, who attended the emergency department with fever without source. Outcome categories were SBI, subdivided in pneumonia and other-SBI (OSBI), and non-SBI. Potential predictors were selected based on previous studies and literature. Four models were developed: a polytomous model, estimating probabilities for three diagnostic categories simultaneously; two sequential dichotomous models, which differed in variable selection, discriminating SBI and non-SBI in step 1, and pneumonia and OSBI in step 2; and model 4, where each outcome category was opposed to the other two. The models were compared with respect to the area under the receiver-operating characteristic curve (AUC) for each of the three outcome categories and to the variable selection. RESULTS: Small differences were found in the variables that were selected in the polytomous and dichotomous models. The AUCs of the three outcome categories were similar for each modeling strategy. CONCLUSION: A polytomous logistic regression analysis did not outperform sequential and single application of dichotomous logistic regression analyses in diagnosing SBIs in children with FWS.     

The influence of health and lifestyle characteristics on the relation of serum 25-hydroxyvitamin D with risk of colorectal and breast cancer in postmenopausal women

The authors' objective was to discern whether lifestyle or health-related factors were confounders, effect modifiers, or irrelevant with regard to understanding observational associations of serum 25-hydroxyvitamin D (25(OH)D) with colorectal and breast cancer. The authors conducted nested case-control studies of colorectal cancer (310 cases, 310 controls) and breast cancer (1,080 cases, 1,080 controls) in the Women's Health Initiative Calcium and Vitamin D Clinical Trial (1994-2005). Case-control matching factors included age, latitude, race/ethnicity, and blood collection date. Serum 25(OH)D was assayed in baseline fasting blood. Conditional logistic regression was used to estimate odds ratios for each cancer by serum 25(OH)D concentration, comparing the relative effects of successively adding body mass index, physical activity, and other health and lifestyle characteristics particular to each cancer. In models with matching factors only, low (vs. high) serum 25(OH)D was associated with a colorectal cancer odds ratio of 2.72 (95% confidence interval (CI): 1.55, 4.77) and a breast cancer odds ratio of 1.33 (95% CI: 1.02, 1.72). In multivariate-adjusted models for colorectal cancer, the association strengthened (OR = 4.45, 95% CI: 1.96, 10.10). However, in multivariate-adjusted breast cancer models, associations were no longer significant (OR = 1.06, 95% CI: 0.78, 1.43). Adjusting for health and lifestyle characteristics has differential effects depending on the cancer site; when modeling such relations, investigators should take these factors into account.     

Maternal cigarette smoking and the risk of pregnancy-induced hypertension and eclampsia

BACKGROUND: Although previous studies have found that maternal smoking decreases the risk of pregnancy-induced hypertension (PIH), the difference of this effect between primiparous and multiparous women has not been well studied and the results of the exposure-response relationships between maternal smoking and PIH are inconsistent. No previous study has specifically examined the relationship between maternal smoking and eclampsia. METHODS: We analysed data from a population-based retrospective cohort study of 3 153 944 singleton pregnancies in the US. The data were derived from the national linked birth/infant mortality database for 1998. Multiple logistic regressions were used to describe the relationship between cigarette smoking and PIH and eclampsia. RESULTS: The adjusted odds ratios (ORs) [95% confidence intervals (95% CIs)] for PIH were 0.80 (0.77-0.83) for primiparous women and 0.81 (0.78-0.83) for multiparous women among smokers compared with non-smokers. The corresponding adjusted ORs (95% CIs) for eclampsia were 0.74 (0.66-0.82) and 0.75 (0.68-0.83), respectively. For PIH, the adjusted OR (95% CI) for smokers vs non-smokers were 0.82 (0.79-0.86), 0.81 (0.78-0.83), 0.80 (0.77-0.83), and 0.88 (0.79-0.98), respectively, for 1-5, 6-10, 11-20, and >20 cigarettes per day (test for trend: P = 0.86). The corresponding figures for eclampsia were 0.85 (0.75-0.95), 0.74 (0.66-0.82), 0.68 (0.58-0.78), and 0.73 (0.49-1.04), respectively (test for trend: P = 0.02). CONCLUSION: Maternal cigarette smoking decreases the risk of PIH and eclampsia, with a significant inverse exposure-response relationship apparent for eclampsia.     

Simple dichotomous updating methods improved the validity of polytomous prediction models

ObjectivesPrediction models may perform poorly in a new setting. We aimed to determine which model updating methods should be applied for models predicting polytomous outcomes, which often suffer from one or more categories with low prevalence.Study Design and SettingWe used case studies on testicular and ovarian tumors. The original regression models were based on 502 and 2,037 patients and validated on 273 and 1,107 patients, respectively. The polytomous models combined dichotomous models for category A vs. B + C and B vs. C (sequential dichotomous modeling). Simple recalibration, revision, and redevelopment methods were considered. To assess discrimination (using dichotomous and polytomous c-statistics) and calibration (by comparing observed and expected prevalences) of these methods, the validation data were divided into updating and test parts. Five hundred such divisions were randomly generated, and the average test set results reported.ResultsNone of the updating methods could improve discrimination of the original models, but recalibration, revision, and redevelopment strongly improved calibration. Redevelopment was unstable with respect to overfitting and performance.ConclusionSimple dichotomous updating methods behaved well when applied to polytomous models. Our results suggest that recalibration is preferred, but larger validation sets may make revision or redevelopment a sensible alternative.     

Prehypertension in the Ashanti region of Ghana, West Africa: an opportunity for early prevention of clinical hypertension

OBJECTIVE: To assess prehypertension among Ghanaian adults in the Ashanti region of Ghana, West Africa. DESIGN: Cross-sectional study. PARTICIPANTS: There were 1431 participants aged 18 years or more. Prehypertension was defined as blood pressure of 120-139/80-89 mmHg. MAIN OUTCOME MEASURES: Prehypertension. RESULTS: Overall, 31% of the study population were normotensive, 40% were prehypertensive and 29% were hypertensive. Prehypertension was more common in non-hypertensive males than non-hypertensive females (66% vs 49%, P<0.001). Prehypertension was also more common in those aged 35 years compared with those aged <35 years (P<0.001), and in overweight and obese people compared with people of normal weight (P=0.03). In a multivariate logistic regression model, male sex [odds ratio (OR) 2.36; 95% confidence interval (CI) 1.77-3.15; P<0.001], age 35-49 years (OR 1.56; 95% CI 1.12-2.18; P<0.01) and 50 years (OR 2.13; 95% CI 1.33-3.42; P=0.002)], overweight (OR 1.61; 95% CI 1.09-2.36; P=0.02) and obesity (OR 2.71; 95% CI 1.40-5.24; P=0.003) were independently associated with higher odds of prehypertension, whilst current smoking (OR 0.36; 95% CI 0.16-0.81; P=0.01) was associated with lower odds of prehypertension. CONCLUSION: Prehypertension is very common among non-hypertensive subjects in the Ashanti region of Ghana. As a large proportion of people with prehypertension will progress to clinical hypertension, targeting these people early with lifestyle modifications such as weight reduction may provide important long-term benefits.     

Parenteral nutrition as a risk factor for central venous catheter-related infection

BACKGROUND: The role of parenteral nutrition (PN) therapy as an independent risk factor for central venous catheter (CVC)-related infection in nonselected adult patients is not well established. The aim of this study was to evaluate PN as a risk factor for central venous catheter-related infection in nonselected adult patients in a general university hospital. METHODS: Patients using central venous catheters, exposed or nonexposed to PN, were prospectively followed for development of central venous catheter-related infection. RESULTS: One hundred fifty-three patients were studied; 28 developed central venous catheter-related infection. Patients with central venous catheter-related infection presented higher frequency of PN use than patients without infection (60.7 vs 34.4%; p = .010). Multivariate Cox analysis showed that PN (relative risk (RR) = 3.30; 95% confidence interval [CI], 1.30-8.34; p = .012) was the only risk factor for central venous catheter-related infection. Malnutrition (RR = 0.45; 95% CI, 0.15-1.34; p = .152), days of hospitalization before central venous catheter insertion (RR = 1.00; 95% CI, 0.98-1.02; p = .801), and sustained hyperglycemia (RR = 0.49; 95% CI, 0.98-1.21; p = .091) were not significant in the model. Multiple logistic regression revealed that mal-nutrition (odds ratio [OR] = 8.05; 95% CI, 1.85-35.03; p = .005), central venous catheter indication for surgical-related pathology (OR = 7.26; 95% CI, 2.51-21.04; p < .001), sustained hyperglycemia (OR = 4.34; 95% CI, 1.79-10.52; p = .001), and days of hospitalization before central venous catheter insertion (OR = 1.04; 95% CI, 1.01-1.07; p = .004) were associated with PN use after adjustment for Assessment Score Intervention System score (OR = 0.33; 95% CI, 0.14-0.80; p = .014). CONCLUSIONS: PN therapy is an independent risk factor for central venous catheter-related infection in nonselected hospitalized adult patients.     

Work-related assault injuries among nurses.

Work-related violence is a major public health problem; however, there is a serious deficiency in the knowledge of risk factors for this problem. The purpose of this case-control study was to identify risk factors for work-related assault injuries among nurses. We used unconditional logistic regression to model the dependence of work-related assault injuries on each exposure of interest and the respective confounders. We found a decreased rate for the presence of security personnel (RR = 0.40; 95% CI = 0.19-0.82). We found increased rates for the following factors: the perception that administrators considered assault to be part of the job (RR = 8.14; 95% CI = 3.76-17.60); having received assault prevention training in the current workplace (RR = 4.64; 95% CI = 2.33-9.23); a high (>5) vs. low (<2) patient/personnel ratio (RR = 2.54; 95% CI = 1.13-5.70); working predominantly with patients with mental illness (RR = 3.5; 95% CI = 1.41-8.85); and working with patients who had more than 1- to 4-week and more than 4-week lengths of stay in the institution vs. <1 day (RR = 8.85; 95% CI = 1.58-49.52 and 4.25; 95% CI = 1.17-15.39, respectively).     

Alcohol drinking frequency in relation to subsequent changes in waist circumference

BACKGROUND: Cross-sectional studies have reported a lower prevalence of abdominal obese persons among frequent drinkers than among nonfrequent drinkers. OBJECTIVE: We tested the hypothesis that drinking frequency is associated with subsequent changes in waist circumference. DESIGN: Data come from a prospective cohort study conducted in 1993-1997 (baseline) and 1999-2002 (follow-up) and included 43 543 men and women. Baseline information on alcohol drinking frequency was related to 1) change in waist circumference by linear regression and 2) major gain and major loss in waist circumference (defined as waist change in the lowest or highest quintile of waist changes) by polytomous logistic regression, also taking into account amount of alcohol intake. RESULTS: Drinking frequency was inversely associated with changes in waist circumference in women and was unassociated with changes in waist circumference in men. Drinking frequency was unassociated with major waist loss but was inversely associated with major waist gain: odds ratios among men were 0.97 (95% CI: 0.73, 1.28), 0.95 (95% CI: 0.81, 1.12), 0.88 (95% CI: 0.77, 0.99), 0.82 (95% CI: 0.71, -0.95), and 0.79 (95% CI: 0.69, 0.9) for never drinking, drinking on 1, 2-4, 5-6, and 7 d/wk, respectively, compared with men who drank alcohol on <1 d/wk (P for trend < 0.0001). Results for women were similar. Adjustment for the amount of alcohol intake or total energy intake did not affect results considerably. CONCLUSIONS: Drinking pattern may be associated with development of abdominal obesity; in this prospective study, drinking frequency was inversely associated with major waist gain and was unassociated with major waist loss.     

咖啡摄入量与心血管死亡率关系的剂量-反应Meta分析

目的 探讨咖啡每日摄入量与心血管死亡率的关系。方法 计算机检索PubMed、EMbase、The Cochrane、CBM、WanFang Data和CNKI 数据库,搜集有关咖啡摄入量与心血管疾病的相关研究,检索时限均从建库至2020年4月。由两名研究者独立筛选文献、提取文献并评价纳入研究的偏倚风险后,采用Stata 14.0进行剂量反应meta分析,并对纳入的文献进行方法学质量评价。结果 共纳入26篇队列研究,包括2 046 690例受试者。剂量-反应meta分析结果显示,咖啡摄入量每天每增加1杯心血管死亡率下降约3%（RR = 0.97,95%CI:0.96～0.98）,差异具有统计学意义,且存在一种非线性剂量反应关系（P for non - linearity:＜0.01）。与不喝咖啡的人群相比,每天喝1～8杯咖啡的人群相对死亡率分别为（RR = 0.90,95%CI:0.87～0.92）、（RR = 0.84,95%CI:0.81～0.87)、（RR = 0.82,95%CI:0.79～0.84）、（RR = 0.81,95%CI:0.78～0.84）、（RR = 0.81,95%CI:0.78～0.84）、（RR = 0.81,95%CI:0.78～0.84）、（RR = 0.82,95%CI:0.79～0.85）、（RR = 0.83,95%CI:0.80～0.87）。与不喝咖啡人群相比,meta分析结果显示喝咖啡人群的相对死亡率平均为（RR = 0.83,95%CI:0.81～0.85）,可以降低17%的死亡率,差异具有统计学意义。结论 饮用咖啡可以降低心血管死亡率,每日饮用2～4杯最佳。     

Diet diversity and colorectal cancer

BACKGROUND: Food diversity has been recommended to achieve a healthy diet and prevent cancer. The relation between diet diversity and the risk of colorectal cancer was investigated using data from a multicenter case-control study carried out between 1992 and 1996 in Italy. METHODS: The study included 1225 subjects with cancer of the colon (688 men and 537 women), 728 with cancer of the rectum (437 men and 291 women), and 4154 controls (2073 men and 2081 women) residing in the same geographical areas. Odds ratios (ORs) of colon and rectal cancer and the corresponding 95% confidence intervals (CI) according to food diversity were derived from unconditional multiple logistic regression equations. RESULTS: For colon cancer, an inverse association for total diversity was found in males (adjusted OR of 0.65 for the highest vs the lowest quintile of total diversity; 95% CI: 0.46-0.93) and in females (OR = 0.85; 95% CI: 0.57-1.26). With respect to specific food groups, there was an inverse association only with diversity within vegetables (OR = 0.66; 95% CI: 0.54-0.81 in colon cancer and OR = 0.71; 95% CI: 0.55-0.91 in rectal cancer). CONCLUSIONS: This study suggests that total diversity is moderately related to a decreased risk of colorectal cancer risk. A better understanding of the potential influence of dietary patterns on colorectal cancer is needed.     

Food groups as predictors for short-term weight changes in men and women of the EPIC-Potsdam cohort

This study examined the effect of food group intake on subsequent 2-y weight change. Food-frequency questionnaire-based food intake data of 17,369 nonsmoking subjects of the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam cohort were examined in their relation to a subsequent weight change. Dietary data, collected from 1994 to 1998, were grouped into 24 food groups. Weight change per year follow-up was the outcome of interest; large weight gain was defined as > or =2 kg; small weight gain as > or =1 kg to <2 kg; large weight loss as < or = -2 kg; small weight loss as < or = -1 kg to > -2 kg and weight maintenance as +/- 1 kg. For each food group, a separate polytomous logistic regression model with stable weight as the reference group was constructed, controlling for age, body mass index, previous weight change, and behavioral and lifestyle factors. Odds ratios (OR) and 95% confidence intervals (CI) estimated the increase in risk associated with each 100 g/d increment in food group intake. In women, consumption of high energy, high fat food groups significantly predicted large weight gain, e.g., fats (OR = 1.75; 95% CI, 1.01-3.06), sauces (OR = 2.12; 95% CI, 1.17-3.82) and meat (OR = 1.36; 95% CI, 1.04-1.79), and the consumption of cereals predicted large weight loss (OR = 1.43; 95% CI, 1.09-1.88). In men, intake of high energy, high sugar foods, i.e., sweets, was significantly predictive of large weight gain (OR = 1.48; 95% CI, 1.03-2.13). Our data show that a diet rich in high fat and high energy foods predicts short-term weight gain even if controlled for many potential confounding factors.     

Dietary Intakes of Selected Nutrients and Food Groups and Risk of Cervical Cancer

We investigated the relationships between intakes of selected dietary nutrients and food groups and risk of cervical cancer in a hospital-based, case-control study including 239 cases diagnosed with squamous cell carcinoma of the cervix and 979 hospital patients with nonneoplastic diagnoses who completed a self-administered questionnaire between 1982 and 1998 at Roswell Park Cancer Institute. Odds ratios (OR) and 95% confidence intervals (CI) were estimated by unconditional logistic regression adjusting for age, education, smoking status, use of oral contraceptives, barrier contraceptives and spermicides, family history of cervical cancer, year questionnaire completed, and energy intake. Significant reductions in risk of approximately 40–60% were observed for women in the highest vs. lowest tertiles of dietary fiber (OR = 0.59, 95% CI = 0.37–0.94), vitamin C (OR = 0.52, 95% CI = 0.33–0.80), vitamin E (OR = 0.44, 95% CI = 0.27–0.72), vitamin A (OR = 0.47, 95% CI = 0.30–0.73), α -carotene (OR = 0.41, 95% CI = 0.27–0.63), β -carotene (OR = 0.44, 95% CI = 0.29–0.68), lutein (OR = 0.51, 95% CI = 0.33–0.79), folate (OR = 0.55, 95% CI = 0.34–0.88), and total fruit and vegetable intake (OR = 0.52, 95% CI = 0.34–0.77). Our findings suggest that a diet rich in plant-based nutrients may be important in reducing the risk of cervical cancer.     

不孕不育特征与夫妻双方高血压患病风险的关联研究

目的 了解不孕不育夫妇高血压患病现况,探讨不孕不育特征与两性高血压患病风险的关联。方法 本研究依托不孕不育队列开展。不孕不育特征包括是否患不孕不育、不孕不育类型、原因及年限。采用多因素logistic回归模型,分性别分析不孕不育特征与高血压的关联。结果 1 312对不孕不育夫妇中,不孕症女性和不育症男性高血压患病率均显著高于同性别对照组（女:18.6% vs. 13.2%;男:21.5% vs. 14.3%）。女性不孕（OR＝1.64,95％CI:1.13～2.38）、双方共同原因不孕症（OR＝2.15,95％CI:1.11～4.15）、继发性不孕（OR＝1.58,95％CI:1.17～2.13）和不孕年限≥3年（OR＝1.96,95％CI:1.29～2.97）会显著增加女方高血压患病风险;男性不育（OR＝1.79,95％CI:1.29～2.48）、双方共同原因不育症（OR＝1.69,95％CI:1.12～2.56）、继发性不育（OR＝1.52,95％CI:1.00～2.39）和不育年限≥3年（OR＝1.97,95％CI:1.23～3.14）会显著增加男方高血压患病风险。结论 确诊不孕不育、继发性不孕不育、双方共同原因不孕不育及长不孕不育年限是不孕不育夫妇患高血压的风险因素。     

Effect of dietary intake of phytoestrogens on estrogen receptor status in premenopausal women with breast cancer

Although many dietary studies have focused on breast cancer risk, few have examined dietary influence on tumor characteristics such as estrogen receptor (ER) status. Because phytoestrogens may modulate hormone levels and ER expression, we analyzed ER status and phytoestrogen intake in a case-case study of 124 premenopausal breast cancer patients. We assessed intake with a food-frequency questionnaire and obtained ER status from medical records. Rather than focusing on risk, we evaluated whether low intakes were more strongly associated with ER-negative tumors than with ER-positive disease. In logistic regression adjusting for potential confounders, threefold greater risks of ER-negative tumors relative to ER-positive tumors were associated with low intake of the isoflavones genistein (odds ratio, OR=3.50; 95% confidence interval, CI=1.43-8.58) and daidzein (OR=3.10; 95% CI=1.31-7.30). Low intake of the flavonoid kaempferol (OR=0.36; 95% CI=0.16-0.83), the trace element boron (OR=0.33; 95% CI=0.13-0.83), and the phytosterol beta-sitosterol (OR=0.42; 95% CI=0.18-0.98) were associated with decreased risk of ER-negative tumors relative to ER-positive disease. Other phytoestrogens were not significantly associated with ER status. Thus, in premenopausal patients, some phytoestrogens may affect breast carcinogenesis by influencing ER status. Such findings suggest new directions for mechanistic research on dietary factors in breast carcinogenesis that may have relevance for prevention and clinical treatment.     

Soy and isoflavone intake are associated with reduced risk of ovarian cancer in southeast china

To investigate whether intake of soy and isoflavones has an inverse association with ovarian cancer risk, a case-control study was conducted in Hangzhou, China. Cases were 254 patients with histologically confirmed epithelial ovarian cancer. The 652 controls comprised 340 hospital visitors, 261 non-neoplastic hospital outpatients, and 51 women recruited from the community. Habitual dietary intakes including 9 soy foods were measured by face-to-face interview using a validated and reliable food-frequency questionnaire. Unconditional logistic regression analyses were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) accounting for age, demographic characteristics, hormonal factors, and total energy intake. Intake of soy and isoflavones was inversely related to the risk of ovarian cancer. Compared with the highest versus the lowest quartile intake, the ORs were 0.50 (95% CI = 0.31-0.82) for total soy foods and 0.51 (95% CI = 0.31-0.85) for isoflavones. Among subgroups of soy foods and isoflavones, the ORs for soybeans, bean curd, daidzein, genistein, and glycitein were 0.35 (95% CI = 0.22-0.58), 0.49 (95% CI = 0.29-0.81), 0.52 (95% CI = 0.31-0.87), 0.50 (95% CI = 0.30-0.84), and 0.59 (95% CI = 0.35-0.97), respectively.     

Inactivated influenza vaccine effectiveness in children under 6 years of age during the 2002-2003 season

This study was carried out to investigate the effectiveness of influenza vaccine among 2913 children (1512 vaccinees and 1401 nonvaccinees) under 6 years of age during the 2002-2003 season. Study subjects were recruited from 54 paediatric clinics, located in eight areas in Japan. Maximum body temperatures were obtained weekly from parents between 2002 December 16 and 2003 April 13. Influenza-like illness (ILI) was defined as an acute febrile illness (> or =38.0 degrees C) during the peak epidemic period in each study area. The vaccine antigens included were A/New Caledonia/20/99(H1N1), A/Panama/2007/99(H3N2) and B/Shandong/7/97. Vaccine effectiveness was analyzed by comparing the frequencies of ILI between vaccinees and nonvaccinees. The adjusted odds ratio (OR) and its 95% confidence interval (95% CI) were calculated by the proportional odds model using logistic regression with three-level outcome variables (<38.0/38.0-38.9/> or =39.0 degrees C). A significantly decreased OR of vaccination was observed (OR: 0.76; 95% CI: 0.66-0.88), corresponding to a vaccine effectiveness (1-OR) of 24% (95% CI: 12%-34%). When the analysis was confined to those aged > or =2 years, a more pronounced OR (0.67, 0.56-0.79) was obtained with a vaccine effectiveness of 33% (21%-44%). On the other hand, no significant vaccine effectiveness was detected among very young children; the ORs were 1.84 (0.81-4.19) for those <1 year of age and 0.99 (0.72-1.36) for those 1.0-1.9 years of age and 1.07 (0.80-1.44) when these two age groups were combined. Thus, among very young children vaccine effectiveness could not be demonstrated.     

Diagnostic value of oral prednisolone test for chronic obstructive pulmonary disorders

PURPOSE We wanted to determine the diagnostic value of an oral prednisolone test for chronic obstructive pulmonary disorders.METHODS Two hundred thirty-three patients with cough for longer than 14 days, without known chronic obstructive pulmonary disease (COPD) or asthma, participated in a diagnostic study in Dutch primary care between 2006 and 2009. These patients used a 14-day prednisolone test of 30 mg/d and recorded before-after bronchodilator measurements of forced expiratory volume in 1 second (FEV₁). An expert panel determined the presence or absence of COPD and asthma based on an extensive diagnostic workup. The proportion of responders to the prednisolone test (increased FEV₁ exceeding 200 mL or 12% of baseline) per diagnosis group was compared, and the diagnostic value of the test was quantified by logistic regression and analysis of the area under the receiver operating characteristic curve (ROC area).RESULTS In patients with COPD, 23% (14 of 61) responded to the test; in patients with asthma 4% (1 of 25) responded; in patients with asthma and COPD, 7% (1 of 14) responded; and in those without asthma or COPD, 11% (14 of 133) responded. Being a responder was, unexpectedly, associated with COPD (OR = 2.4; 95% confidence interval [CI], 1.1–5.2). After multivariate analysis, adjusting for age, sex, and smoking, the OR = 2.0 (95% CI, 0.8–5.0) and the ROC area did not increase (0.78; 95% CI, 0.72–0.85 vs 0.79; 95% CI, 0.72–0.85).CONCLUSION A response to a prednisolone test was suggestive of COPD, but added no diagnostic value to more easily obtainable characteristics.     

Decline of ambient air pollution levels and improved respiratory health in Swiss children

The causality of observed associations between air pollution and respiratory health in children is still subject to debate. If reduced air pollution exposure resulted in improved respiratory health of children, this would argue in favor of a causal relation. We investigated whether a rather moderate decline of air pollution levels in the 1990s in Switzerland was associated with a reduction in respiratory symptoms and diseases in school children. In nine Swiss communities, 9,591 children participated in cross-sectional health assessments between 1992 and 2001. Their parents completed identical questionnaires on health status and covariates. We assigned to each child an estimate of regional particles with an aerodynamic diameter < 10 microg/m3 (PM10) and determined change in PM10 since the first survey. Adjusted for socioeconomic, health-related, and indoor factors, declining PM10 was associated in logistic regression models with declining prevalence of chronic cough [odds ratio (OR) per 10-microg/m3 decline = 0.65, 95% confidence interval (CI), 0.54-0.79], bronchitis (OR = 0.66; 95% CI, 0.55-0.80), common cold (OR = 0.78; 95% CI, 0.68-0.89), nocturnal dry cough (OR = 0.70; 95% CI, 0.60-0.83), and conjunctivitis symptoms (OR = 0.81; 95% CI, 0.70-0.95). Changes in prevalence of sneezing during pollen season, asthma, and hay fever were not associated with the PM10 reduction. Our findings show that the reduction of air pollution exposures contributes to improved respiratory health in children. No threshold of adverse effects of PM10 was apparent because we observed the beneficial effects for relatively small changes of rather moderate air pollution levels. Current air pollution levels in Switzerland still exceed limit values of the Swiss Clean Air Act; thus, children's health can be improved further.     

Physical violence and associated factors: a population-based study in Southern Brazil

OBJECTIVE: To estimate the prevalence of physical violence and its association with sociodemographic aspects, stressful life events, and the use of health services due to emotional problems. METHODS: A cross-sectional population-based study was conducted with a sample of 1,954 14-year-old or older inhabitants of the city of Canoas (Southern Brazil). They were selected by means of conglomerate sampling according to a pre-established system. Data were obtained in visits to households by means of a confidential semi-structured questionnaire. A bivariate analysis was carried out through multinomial logistic regression, and the multivariate analysis by polytomous logistic regression, categorizing the outcome by age group. RESULTS: The findings show a prevalence of 9.7% (CI 95%: 8.37;11.03) and association with: women 20 years old and older (OR=2.74; CI 95%: 1.52;4.94); higher schooling rate (p<0.03); higher experience of stressful life events at 20 years of age or more (OR=6.61; CI 95%: 2.71;16.1); and doctors' appointments due to emotional problems as of 10 years of age (p>0.001). CONCLUSIONS: The prevalence of physical violence in the population was significant, resulting in important emotional consequences and impact on health services, requiring capacity building of the professionals in the field.