Variability in physician referral decisions

BACKGROUND: Because it is possible that part of the variability in frequency of interventions and even in outcomes results from the variability in referral patterns of primary care physicians, our objectives were to examine primary care physician decision making about referrals for several common adult and childhood conditions. METHODS: One hundred thirty-six family physicians in 80 office-based practices recorded reasons for referral to the most common types of specialists and the expectation of the specialist for conditions with at least seven referrals to each specialist. RESULTS: By far the most referrals were expected to be short-term (< 12 months); for more than 50%, the referrals were for consultation only (rather than direct intervention). For most of the 10 types of conditions, there were no apparent differences in reason for or expectation of the referral that would explain the choice of different types of specialists for referral. Expectations for shared care were generally more common in referrals to nonphysicians than to physicians. CONCLUSIONS: This study revealed unexplained variability among family physicians in the specialists to whom patients are referred for specific conditions. Why some patients with the same condition are referred to surgeons and others to medical specialists is unclear, at least in the context of expectations for referral as being long-term vs short-term or consultative vs referral for definitive management. The impact of this variability on costs and outcome could be considerable and deserves more intensive study.     

Characteristics of maternal employment during pregnancy: effects on low birthweight.

BACKGROUND: Although maternal employment is considered a risk factor for low birthweight (LBW), the manner in which employment might affect birthweight is poorly understood. In this analysis, selected characteristics of employment during pregnancy were examined for effects on pregnancy outcomes. METHODS: Work characteristics included the number of hours per week, physical activities, and environmental conditions. The outcomes of interest were fetal growth retardation (less than 2500 grams at term) and preterm delivery (less than 37 weeks). The study population consisted of 2711 non-Black, married mothers who participated in the 1980 National Natality Survey (NNS). The NNS data were merged with data from the 1977 revision of The Dictionary of Occupational Titles (DOT) from which measures of occupational physical activities and environmental exposures were obtained. Logistic regression was used in the analysis. RESULTS: Those who worked 40 or more hours per week were more likely than women who worked fewer hours to have a low birthweight delivery at greater than or equal to 37 weeks. No physical or environmental characterics of work were associated with low birthweight or preterm delivery. CONCLUSIONS: Non-Black married American women may face a risk of delivering low-birthweight babies at or near term only if they work 40 or more hours each week. However, the lack of risk associated with other characteristics of work may be a function of measurement error in the DOT data source or of low levels of exposure in the analysis population.     

Variability and predictors of changes in water use during pregnancy

Disinfection by-products in tap water have been found in some studies to be associated with adverse pregnancy outcomes, but little is known about how water use and consumption might change during early pregnancy. Estimating water-related activities only at one time during pregnancy could easily lead to exposure misclassification. To evaluate changes in water use among pregnant women, we used data from a large epidemiologic study in which 1990 women were interviewed around 9 and 20 weeks' gestation. The water variables that were examined included ingestion of cold and hot tap water as well as of bottled water, showering and bathing. Changes were detected between early and mid-pregnancy for ingested cold tap water and showering. Thirty-three percent of the subjects changed cold-water ingestion by > or =1.0 liters/day and 44% changed their time showering by > or =35 min per week during this period. Increases in cold tap water intake were associated with age >35 years, income < $40,000, and non-Hispanic white ethnicity. We also found that the proportion of the total variation due to within-subject variability was 62% for hot tap water ingestion but only 35% for showering and approximately 50% for cold tap water, bottled water and bathing. Limited resources in epidemiologic studies often require a decision between collecting data for a large number of people or collecting multiple measurements for a smaller number of people. The results in this study will be useful to researchers who need to determine where to invest their effort when assessing water-related exposures and should help in evaluation of previously performed studies.     

Variability and predictors of urinary bisphenol A concentrations during pregnancy

Background

Prenatal bisphenol A (BPA) exposure may be associated with developmental toxicity, but few studies have examined the variability and predictors of urinary BPA concentrations during pregnancy.

Objective

Our goal was to estimate the variability and predictors of serial urinary BPA concentrations taken during pregnancy.

Methods

We measured BPA concentrations during pregnancy and at birth in three spot urine samples from 389 women. We calculated the intraclass correlation coefficient (ICC) to assess BPA variability and estimated associations between log₁₀-transformed urinary BPA concentrations and demographic, occupational, dietary, and environmental factors, using mixed models.

Results

Geometric mean (GM) creatinine-standardized concentrations (micrograms per gram) were 1.7 (16 weeks), 2.0 (26 weeks), and 2.0 (birth). Creatinine-standardized BPA concentrations exhibited low reproducibility (ICC = 0.11). By occupation, cashiers had the highest BPA concentrations (GM: 2.8 μg/g). Consuming canned vegetables at least once a day was associated with higher BPA concentrations (GM = 2.3 μg/g) compared with those consuming no canned vegetables (GM = 1.6 μg/g). BPA concentrations did not vary by consumption of fresh fruits and vegetables, canned fruit, or store-bought fresh and frozen fish. Urinary high-molecular-weight phthalate and serum tobacco smoke metabolite concentrations were positively associated with BPA concentrations.

Conclusions

These results suggest numerous sources of BPA exposure during pregnancy. Etiological studies may need to measure urinary BPA concentrations more than once during pregnancy and adjust for phthalates and tobacco smoke exposures.     

Mental retardation in ten-year-old children in relation to their mothers' employment during pregnancy

We conducted a case-control study to examine relationships between potential risk factors in women's prenatal occupational histories and subsequent mental retardation in their 10-year-old children. Children with mental retardation (intelligence quotient less than 71) were identified from special education records maintained by the public school systems in the metropolitan Atlanta area and from records of various medical and social service agencies serving children with special needs. Control children were chosen from the rosters of 10-year-olds who were enrolled in regular education classes in the local public school systems. To obtain occupational histories, sociodemographic data, and other information, we interviewed 352 natural mothers (67%) of 525 case children and 408 natural mothers (64%) of 636 control children. We computed odds ratios for each of 25 selected occupation, industry, and agent categories controlling for maternal education, birth order, and race. Most comparisons yielded odds ratios that were not indicative of unusual risks, but we did find lower than expected risks among children of teachers and health-care professionals. We also found a strong, positive association between mental retardation and maternal employment in the textile and apparel industries. The findings are useful for planning the direction of future studies of childhood cognitive ability to focus on specific parental occupations or industries. © 1993 Wiley-Liss, Inc.

1 This article is a US Government work and, as such, is in the public domain in the United States of America.

     

孕期管理对妊娠期糖尿病产妇的妊娠结局影响分析

目的:探讨孕期管理对妊娠期糖尿病产妇的妊娠结局影响。方法:选择妊娠期糖尿病的患者90例,随机分为干预组和对照组各45例,干预组实施孕期管理,对照组未实施孕期管理,比较两组产妇的妊娠结局。结果:干预组产妇在妊高征、羊水过多、产后出血及生殖道感染方面显著少于对照组(P<0.05);且干预组的新生儿在各种并发疾病方面显著少于对照组(P<0.05)。结论:妊娠期糖尿病孕期管理对产妇妊娠期控制好产妇的血糖、血脂,改善妊娠结局,减少并发症的发生有积极意义。     

Relationships between physician advice and tobacco and alcohol use during pregnancy

INTRODUCTION: We sought to examine relationships between physician advice and use of tobacco and alcohol during pregnancy among 683 women in the upper Midwest. METHODS: Data on risk of substance use during pregnancy were analyzed using logistic regression analysis. RESULTS: A higher proportion of women used tobacco (34%) than alcohol (25%) during their most recent pregnancy. Women who received advice from a physician to abstain from alcohol reported a lower risk of smoking and drinking during pregnancy than women who did not receive such advice. Risk of smoking and drinking during pregnancy was also common among women who reported early onset of alcohol use. CONCLUSIONS: Results suggest that physician advice regarding alcohol use during pregnancy is protective against maternal smoking and drinking during pregnancy.     

Guidelines for corporate covenants and physician employment agreements

Failure to set forth an appropriate framework for collaboration and employment between physicians can be the source of much distress and acrimony. This article details some guidelines based on the author's consulting practice that will help physicians structure corporate or partnership agreements and terms of employment that are fair and clear.     

Paternal employment in solvent related occupations and adverse pregnancy outcomes.

Washington State birth certificates were examined for associations between adverse pregnancy outcomes and paternal employment in solvent exposed occupations. Four cohorts defined by live, singleton births to fathers usually employed as auto body shop workers, painters (construction and maintenance), printers, or fibreglass workers were compared retrospectively with both a systematically selected control cohort and a low solvent exposed, occupationally defined control cohort (paternal electricians). The effects of maternal race and medical illness were controlled by sample restriction; maternal age and gravidity by stratified analysis. There was evidence of increased risk of low birth weight for infants born to fathers employed as body shop workers (relative risk = 1.6; 95% confidence interval = 1.1-2.4) or painters (RR = 1.4; CI = 0.9-2.1) when compared with the systematically selected controls but not with the electrician controls. The excess risk appeared stronger when only term infants were analysed suggesting a mechanism of growth retardation rather than prematurity. There was no evidence of increased risk among the other exposed cohorts or for other adverse pregnancy outcomes. Several design features limit the interpretation of the findings and confirmation by other studies is needed.     

Congenital anomalies in the offspring of nurses: association with area of employment during pregnancy

The purpose of this study was to determine whether registered nurses in specific areas of employment during pregnancy had a higher risk for congenital anomalies in their offspring. An offspring cohort (n = 22,611) was created through linkage of the British Columbia Vital Statistics Agency live and stillbirth records from 1986 to 2000, to a female cohort database of registered nurses. Of these, 16,005 (70.8%) were registered in a specific area of employment when pregnant. Odds ratios were calculated using generalized estimating equations (GEE), binary logistic regression with adjustment for sex, mother's age, and year of birth. Elevated risks of congenital anomalies were found for the singleton offspring of nurses employed in the following areas: operating rooms and pediatric nursing units (heart anomalies); maternal newborn units (integument); emergency room (respiratory system); and psychiatry (upper alimentary tract). Further research is needed to determine whether these are chance or consistent findings and whether exposure patterns might provide biological plausibility.     

The management of asthma and rhinitis during pregnancy

Asthma and rhinitis frequently complicate pregnancy. The course of asthma may be adversely altered by gestation, placing the mother and fetus at risk. Therefore, pregnant patients with persistent asthma require an aggressive asthma management plan that includes environmental control measures and the use of long-term controller medications. Inhaled corticosteroids (ICSs) are the preferred long-term controller medication for persistent asthma, based on efficacy. However, safety concerns regarding corticosteroids may cause physicians or patients to seek an alternate, less effective treatment during pregnancy. The Food and Drug Administration's pregnancy category ratings are based on animal and human safety data. Because ICSs were previously rated pregnancy category C (i.e., with human studies lacking and animal studies either lacking or positive for fetal risk), other asthma controllers, such as cromolyn and nedocromil, that carry a pregnancy category B rating (i.e., showing no evidence of fetal risk in humans or animal studies negative for fetal risk) appeared to be more desirable for use during pregnancy. One ICS, budesonide, was reclassified as pregnancy category B based on human data supporting its use during pregnancy. In moderate and severe persistent asthma, add-on therapy may be considered, including long-acting beta2-adrenergic agonists, leukotriene receptor antagonists, and theophylline. Because rhinitis may adversely affect quality of life and the course of asthma, recommendations for aggressive management also apply.     

Variability of urinary phthalate metabolite and bisphenol A concentrations before and during pregnancy

Background: Gestational phthalate and bisphenol A (BPA) exposure may increase the risk of adverse maternal/child health outcomes, but there are few data on the variability of urinary biomarkers before and during pregnancy.Objective: We characterized the variability of urinary phthalate metabolite and BPA concentrations before and during pregnancy and the ability of a single spot urine sample to classify average gestational exposure.Methods: We collected 1,001 urine samples before and during pregnancy from 137 women who were partners in couples attending a Boston fertility clinic and who had a live birth. Women provided spot urine samples before (n ≥ 2) and during (n ≥ 2) pregnancy. We measured urinary concentrations of monoethyl phthalate (MEP), mono-n-butyl phthalate (MBP), mono-iso-butyl phthalate, monobenzyl phthalate (MBzP), four metabolites of di-(2-ethylhexyl) phthalate (DEHP), and BPA. After adjusting for specific gravity, we characterized biomarker variability using intraclass correlation coefficients (ICCs) and conducted several surrogate category analyses to determine whether a single spot urine sample could adequately classify average gestational exposure.Results: Absolute concentrations of phthalate metabolites and BPA were similar before and during pregnancy. Variability was higher during pregnancy than before pregnancy for BPA and MBzP, but similar during and before pregnancy for MBP, MEP, and ΣDEHP. During pregnancy, MEP (ICC = 0.50) and MBP (ICC = 0.45) were less variable than BPA (ICC = 0.12), MBzP (ICC = 0.25), and ΣDEHP metabolites (ICC = 0.08). Surrogate analyses suggested that a single spot urine sample may reasonably classify MEP and MBP concentrations during pregnancy, but more than one sample may be necessary for MBzP, DEHP, and BPA.Conclusions: Urinary phthalate metabolites and BPA concentrations were variable before and during pregnancy, but the magnitude of variability was biomarker specific. A single spot urine sample adequately classified MBP and MEP concentrations during pregnancy. The present results may be related to unique features of the women studied, and replication in other pregnancy cohorts is recommended.