In utero opioid exposure and birth outcomes: a systematic review and meta-analysis

Background

The nonmedical use of opioids during pregnancy, either those prescribed or obtained illegally, is a worldwide public health issue. Opioids pass through the placental barrier, which can expose the fetus to maternal opioid use; opioid-exposed babies may experience Neonatal Abstinence Syndrome (or Neonatal Opioid Withdrawal). We conducted a systematic review and meta-analysis to investigate how maternal opioid use during pregnancy may impact infants' birth outcomes.

Methods

We searched PubMed, Embase, PsycInfo, and the Web of Science, and identified 90 articles that met our inclusion criteria. Cohort, case-control and cross-sectional studies comparing birth outcomes of any opioid-exposed group (prescribed or obtained illegally) and a non-exposed comparison group were eligible for our systematic review. An adapted version of the Newcastle-Ottawa-Scale was used for quality assessment of the studies. Due to high heterogeneity between studies, we used random effects models to estimate pooled effects.

Results

In meta-analyses, opioid-exposed infants had lower birthweight (mean difference (MD):-405.9 grams, 95%CI: -472.26,-339.54, N = 37 studies), smaller head circumference (MD:-1.19 cm, 95%CI:-1.41, -0.96,N=22 studies), shorter gestational age (MD:-0.93 weeks, 95%CI: -1.20, -0.66,N= 34 studies), and shorter birth length (MD:-0.97 cm, 95%CI: -1.20, -0.74, N = 15 studies). The pooled relative risk of fatal outcomes was higher among the exposed infants: (RR:2.64, 95%CI: 1.06,6.59). Almost half of the studies were rated as poor, based on the Newcastle Ottawa Scale.

Conclusions

Our meta-analysis provides evidence of a link between opioid use during pregnancy and multiple adverse infant birth outcomes. Efforts should focus on increasing awareness about risks associated with opioid use and provide access to harm reduction measures for people who use opioids preconceptionally and in pregnancy.

Key messages

This meta-analysis provides insight into the magnitude of effects of in-utero opioid exposure on birth outcomes among the included studies. The findings highlight the importance of access to harm reduction measures in the periconceptional period and during pregnancy for people who use opioids.

Prognostic profiles and the effectiveness of assisted conception: secondary analyses of individual patient data

BACKGROUND

At present, it is unclear which treatment strategy is best for couples with unexplained or mild male subfertility. We hypothesized that the prognostic profile influences the effectiveness of assisted conception. We addressed this issue by analysing individual patient data (IPD) from randomized controlled trials (RCTs).

METHODS

We performed an IPD analysis of published RCTs on treatment strategies for subfertile couples. Eligible studies were identified from Cochrane systematic reviews and we also searched Medline and EMBASE. The authors of RCTs that compared expectant management (EM), intracervical insemination (ICI), intrauterine insemination (IUI), all three with or without controlled ovarian stimulation (COS) and IVF in couples with unexplained or male subfertility, and had reported live birth or ongoing pregnancy as an outcome measure, were invited to share their data. For each individual patient the chance of natural conception was calculated with a validated prognostic model. We constructed prognosis-by-treatment curves and tested whether there was a significant interaction between treatment and prognosis.

RESULTS

We acquired data from 8 RCTs, including 2550 couples. In three studies (n = 954) the more invasive treatment strategies tended to be less effective in couples with a high chance of natural conception but this difference did not reach statistical significance (P-value for interaction between prognosis and treatment outcome were 0.71, 0.31 and 0.19). In one study (n = 932 couples) the strategies with COS (ICI and IUI) led to higher pregnancy rates than unstimulated strategies (ICI 8% versus 15%, IUI 13% versus 22%), regardless of prognosis (P-value for interaction in all comparisons >0.5), but at the expense of a high twin rate in the COS strategies (ICI 6% versus 23% and IUI 3% versus 30%, respectively). In two studies (n = 373 couples), the more invasive treatment strategies tended to be more effective in couples with a good prognosis but this difference did not reach statistical significance (P-value for interaction: 0.38 and 0.68). In one study (n = 253 couples) the differential effect of prognosis on treatment effect was limited (P-value for interaction 0.52), perhaps because prognosis was incorporated in the inclusion criteria. The only study that compared EM with IVF included 38 couples, too small for a precise estimate.

CONCLUSIONS

In this IPD analysis of couples with unexplained or male subfertility, we did not find a large differential effect of prognosis on the effectiveness of fertility treatment with IUI, COS or IVF.

The Early Determinants of Adult Health Study

This issue of the Journal features collaborative follow-up studies of two unique pregnancy cohorts recruited during 1959-1966 in the United States. Here we introduce the Early Determinants of Adult Health (EDAH) study. EDAH was designed to compare health outcomes in midlife (age 40s) for same-sex siblings discordant on birthweight for gestational age. A sufficient sample of discordant siblings could only be obtained by combining these two cohorts in a single follow-up study. All of the subsequent six papers are either based upon the EDAH sample or are related to it in various ways. For example, three papers report results from studies that significantly extended the 'core' EDAH sample to address specific questions. We first present the overall design of and rationale for the EDAH study. Then we offer a synopsis of past work with the two cohorts to provide a context for both EDAH and the related studies. Next, we describe the recruitment and assessment procedures for the core EDAH sample. This includes the process of sampling and recruitment of potential participants; a comparison of those who were assessed and not assessed based on archived data; the methods used in the adult follow-up assessment; and the characteristics at follow-up of those who were assessed. We provide online supplementary tables with much further detail. Finally, we note further work in progress on EDAH and related studies, and draw attention to the broader implications of this endeavor.

Hydroxylated PCB metabolites (OH-PCBs) in archived serum from 1950-60s California mothers: a pilot study

We are studying participants selected from the Child Health and Development Studies (CHDS), a longitudinal birth cohort of over 20,000 California pregnancies between 1959 and 1967, for associations between maternal body burden of organochlorine contaminants and thyroid function. We designed a pilot study using 30 samples selected among samples with high and low PCB concentrations to evaluate the feasibility of measuring OH-PCBs in the larger study population. GC-ECD and GC-NCI/MS were used to determine PCBs and OH-PCBs as methyl derivatives, respectively. Maternal serum levels of Sigma11PCBs and Sigma8OH-PCB metabolites varied from 0.74 to 7.99 ng/mL wet wt. with a median of 3.05 ng/mL, and from 0.12 to 0.98 ng/mL wet wt. with a median of 0.39 ng/mL, respectively. Average concentrations of Sigma8OH-PCB metabolites in the high PCB group were significantly higher than those in the low PCB group (p < 0.05). The levels of OH-PCB metabolites were dependent on PCB levels (r = 0.58, p < 0.05) but approximately an order of magnitude lower (p < 0.05). The average ratio of Sigma8OH-PCBs to Sigma11PCBs was 0.14 +/- 0.08. The primary metabolite was 4-OH-CB187 followed by 4-OH-CB107. Both of these metabolites interfere with the thyroid system in in vitro, animal, and human studies. OH-PCBs were detectable in all archived sera analyzed, supporting the feasibility to measure OH-PCB metabolites in the entire cohort.

Blood harmane concentrations and dietary protein consumption in essential tremor

BACKGROUND

Beta-carboline alkaloids (e.g., harmane) are highly tremorogenic chemicals. Animal protein (meat) is the major dietary source of these alkaloids. The authors previously demonstrated that blood harmane concentrations were elevated in patients with essential tremor (ET) vs controls. Whether this difference is due to greater animal protein consumption by patients or their failure to metabolize harmane is unknown.

OBJECTIVE

The aim of this study was to determine whether patients with ET and controls differ with regard to 1) daily animal protein consumption and 2) the correlation between animal protein consumption and blood harmane concentration.

METHODS

Data on current diet were collected with a semiquantitative food frequency questionnaire and daily calories and consumption of animal protein and other food types was calculated. Blood harmane concentrations were log-transformed (logHA).

RESULTS

The mean logHA was higher in 106 patients than 161 controls (0.61 +/- 0.67 vs 0.43 +/- 0.72 g(-10)/mL, p = 0.035). Patients and controls consumed similar amounts of animal protein (50.2 +/- 19.6 vs 49.4 +/- 19.1 g/day, p = 0.74) and other food types (animal fat, carbohydrates, vegetable fat) and had similar caloric intakes. In controls, logHA was correlated with daily consumption of animal protein (r = 0.24, p = 0.003); in patients, there was no such correlation (r = -0.003, p = 0.98).

CONCLUSIONS

The similarity between patients and controls in daily animal protein consumption and the absence of the normal correlation between daily animal protein consumption and logHA in patients suggests that another factor (e.g., a metabolic defect) may be increasing blood harmane concentration in patients.

Essential tremor: Occupational exposures to manganese and organic solvents

Occupational exposures to manganese and organic solvents cause parkinsonism as well as prominent action tremor, resembling essential tremor (ET), yet their association with ET has not been studied. These chemicals cause cerebellar pathology. Cerebellar changes have been linked with ET. Using lifetime occupational histories, the authors demonstrated that occupational exposures were similar in cases and controls, which does not support an etiologic link between occupational exposures to these chemicals and ET.

Elevation of blood beta-carboline alkaloids in essential tremor

BACKGROUND

beta-Carboline alkaloids are normal body constituents but are also potent tremor-producing chemicals that are naturally present in the food chain.

OBJECTIVE

To explore the hypothesis that high concentrations of beta-carboline alkaloids are associated with essential tremor (ET).

METHODS

One hundred cases and 100 controls were frequency matched on age, sex, and ethnicity. Blood concentrations of harmane and harmine were quantified by high-performance liquid chromatography, blinded to clinical information.

RESULTS

The mean log blood concentration of harmane was higher in cases than controls (0.72 +/- 0.53 vs 0.51 +/- 0.64 g(-10)/mL; p = 0.01). A nonparametric test on nontransformed data (median harmane = 5.21 g(-10)/mL in cases and 2.28 g(-10)/mL in controls) confirmed this difference (p = 0.005). The mean log blood concentration of harmine was 0.20 +/- 0.48 g(-10)/mL in cases and 0.10 +/- 0.65 g (-10)/mL in controls (p = 0.20). Log harmane concentrations were stratified based on the median value; 62% of cases vs 39% of controls had a high log harmane concentration (p = 0.001). Mean log harmane concentration was similar in the cases with (0.74 +/- 0.58 g(-10)/mL) and without (0.71 +/- 0.50 g(-10)/mL) an affected relative (p = 0.83).

CONCLUSIONS

Blood concentrations of harmane were measured in ET cases compared with controls. Concentrations were elevated in cases with and without a family history of ET.

Use of complementary and alternative medicine among women in New York City: a pilot study

OBJECTIVE

This study documents the use of complementary and alternative medicine (CAM), among White, African American, and Hispanic/Latina women living in New York City. A pilot to a national survey of CAM use among American women, this study explores women's use of categories of CAM and various CAM practitioners, racial and ethnic differences in CAM use, and women's perceptions regarding the effectiveness of CAM. DESIGN AND LOCATION: Data were collected from women residing in New York City using random digit dialing/computer-assisted telephone interviewing (CATI). The sample of 300 had equal numbers of women (n = 100) who self-identified as White, Hispanic/Latina, and African American, equally stratified by age (below and above age 40).

SUBJECTS

Eligibility requirements included self-identification as Anglo/white, African American, or Hispanic/Latina and between ages 18 and 80.

MEASURES

Three distinct categories of CAM were explored: (1) medicinal teas, homeopathic remedies, herbs, vitamins; (2) yoga, meditation, spiritual practices; and (3) manual therapies including chiropractic, massage, acupressure. Health concerns of interest were those frequently described in prior focus groups, and included reproductive health issues (e.g., pregnancy, menstruation, menopause) as well as other common women's health problems (e.g., heart disease, high blood pressure, headaches).

RESULTS

More than half the sample has used a CAM treatment or remedy, and 40% have visited a CAM practitioner. Among users, half have used only one of the CAM categories, approximately one third have used two, and 16% used all three. The category of CAM used most often was medicinal tea/herbs/vitamins; the practitioners visited most frequently were chiropractors (18%) and nutritionists (17%). Racial and ethnic differences in CAM use were minimal, and approximately one third of all treatments used were rated "very effective" by users.

CONCLUSIONS

Substantial utilization of CAM remedies and treatments for a variety of women's health concerns is observed. Further inquiry with larger samples of women is recommended.

Sperm morphology, motility, and concentration in fertile and infertile men

BACKGROUND

Although semen analysis is routinely used to evaluate the male partner in infertile couples, sperm measurements that discriminate between fertile and infertile men are not well defined.

METHODS

We evaluated two semen specimens from each of the male partners in 765 infertile couples and 696 fertile couples at nine sites. The female partners in the infertile couples had normal results on fertility evaluation. The sperm concentration and motility were determined at the sites; semen smears were stained at the sites and shipped to a central laboratory for an assessment of morphologic features of sperm with the use of strict criteria. We used classification-and-regression-tree analysis to estimate threshold values for subfertility and fertility with respect to the sperm concentration, motility, and morphology. We also used an analysis of receiver-operating-characteristic curves to assess the relative value of these sperm measurements in discriminating between fertile and infertile men.

RESULTS

The subfertile ranges were a sperm concentration of less than 13.5 x 10(6) per milliliter, less than 32 percent of sperm with motility, and less than 9 percent with normal morphologic features. The fertile ranges were a concentration of more than 48.0 x 10(6) per milliliter, greater than 63 percent motility, and greater than 12 percent normal morphologic features. Values between these ranges indicated indeterminate fertility. There was extensive overlap between the fertile and the infertile men within both the subfertile and the fertile ranges for all three measurements. Although each of the sperm measurements helped to distinguish between fertile and infertile men, none was a powerful discriminator. The percentage of sperm with normal morphologic features had the greatest discriminatory power.

CONCLUSIONS

Threshold values for sperm concentration, motility, and morphology can be used to classify men as subfertile, of indeterminate fertility, or fertile. None of the measures, however, are diagnostic of infertility.

Methodology, inference and causation: environmental lead exposure and childhood intelligence

Kaufman's critique of the literature on the associations between lead exposure and child intelligence raises important methodological and inferential points. We address the concerns he raises regarding measuring known and unknown confounders, statistical modeling, reverse causality and quality control. Mismeasurement of potential confounders of the lead-IQ relationship, such as parenting skills, parental intelligence, maternal smoking during pregnancy, or otitis media can either strengthen or weaken the estimated association between exposure and child intelligence. Despite some variability in design and measurement, a series of comprehensive prospective investigations in varied populations, by different sets of investigators, provided consistent replication; taken together these studies point to the conclusion that lead exposure has adverse consequences for child development, and that the deficits are likely to be small in comparison to the contribution of measured social factors.

The Yugoslavia Prospective Lead Study: contributions of prenatal and postnatal lead exposure to early intelligence

To investigate associations between the timing of lead (Pb) exposure on early intelligence, we examined the results of psychometric evaluations at ages 3, 4, 5, and 7 years, from 442 children whose mothers were recruited during pregnancy from a smelter town and a non-lead-exposed town in Yugoslavia. We compared the relative contribution of prenatal blood lead (BPb) with that of relative increases in BPb in either the early (0-2 years) or the later (from 2 years on) postnatal period to child intelligence measured longitudinally at ages 3 and 4 (McCarthy GCI), 5 (Wechsler Preschool and Primary Scale of Intelligence-Revised, WPPSI-R IQ), and 7 (Wechsler Intelligence Scale for Children-version III, WISC-III IQ), controlling for: Home Observation for Measurement of the Environment (HOME) quality; maternal age, intelligence, education, and ethnicity; and birthweight and gender. Elevations in both prenatal and postnatal BPb were associated with small decrements in young children's intelligence.

Lead exposure and motor functioning in 4(1/2)-year-old children: the Yugoslavia prospective study

OBJECTIVE

To investigate associations between lead exposure and early motor development.

STUDY DESIGN

We conducted standardized assessments of motor function (Bruininks-Oseretsky Test of Motor Proficiency and Beery Developmental Test of Visual-Motor Integration) at age 54 months in 283 children whose mothers were recruited in pregnancy from a smelter town and a non-lead-exposed town in Yugoslavia and who have been monitored twice yearly since birth. Blood lead concentration (BPb) was summarized in a measure reflecting the average of the child's semiannual serial log BPbs through 54 months.

RESULTS

Multiple regression showed that taken together, anthropometric measures (birth weight, body mass index) and markers of a stimulating and organized home life (HOME scale, parental education and intelligence, availability of siblings) explained a significant 10% to 18% of the variance in motor functioning. Beyond these contributions, BPb was significantly associated with poorer fine motor and visual motor function but was unrelated to gross motor coordination.

CONCLUSIONS

Modest associations between early lead exposure and fine motor and visual motor functioning appear even after statistical adjustment is done for other contributors to motor development. Associations with BPb are specific to these areas of motor skill; gross motor development was unaffected.

Use of complementary and alternative medicine among African-American and Hispanic women in New York City: a pilot study

OBJECTIVE

To explore the use of complementary and alternative medicine (CAM) among African-American and Hispanic women residing in New York City, including use of specific treatments and practitioners, perceived effectiveness of CAM, and culturally specific words or expressions for CAM.

METHODS

Focus groups were conducted with two groups of African-American and two groups of Hispanic women (age 18-40 and 41-80) as preparation for the development of a quantitative instrument to assess the prevalence and determinants of CAM use among women of various ethnic backgrounds. Participants were recruited using a standard random digit dial procedure.

RESULTS

The most commonly used CAM remedies were teas and herbs, vitamins and nutritional supplements, prayer and spiritual healing, meditation and relaxation techniques. Practitioners most frequently seen were chiropractors, herbalists, and acupuncturists. Use of alternative remedies and practitioners, particularly the latter, was most common among older women in both groups. Younger Hispanic women reported the most skepticism toward CAM, especially when it was used by relatives as a substitute for conventional medical care. Overall, these African-American and Hispanic women used CAM for a wide range of health conditions and for prevention. Few racial and ethnic differences emerged in patterns of CAM use for either self-care or treatment by practitioners, but there was a distinct age variation, especially in attitudes toward CAM.

Efficacy of superovulation and intrauterine insemination in the treatment of infertility. National Cooperative Reproductive Medicine Network

BACKGROUND

Induction of superovulation with gonadotropins and intrauterine insemination are frequently used to treat infertility. We conducted a large, randomized, controlled clinical trial of these treatments.

METHODS

We studied 932 couples in which the woman had no identifiable infertility factor and the man had motile sperm. The couples were randomly assigned to receive intracervical insemination, intrauterine insemination, superovulation and intracervical insemination, or superovulation and intrauterine insemination. Treatment continued for four cycles unless pregnancy was achieved.

RESULTS

The 231 couples in the group treated with superovulation and intrauterine insemination had a higher rate of pregnancy (33 percent) than the 234 couples in the intrauterine-insemination group (18 percent), the 234 couples in the group treated with superovulation and intracervical insemination (19 percent), or the 233 couples in the intracervical-insemination group (10 percent). Stratified, discrete-time Cox proportional-hazards analysis showed that the couples in the group treated with superovulation and intrauterine insemination were 3.2 times as likely to become pregnant as those in the intracervical-insemination group (95 percent confidence interval, 2.0 to 5.3) and 1.7 times as likely as those in the intrauterine-insemination group (95 percent confidence interval, 1.2 to 2.6). The couples in the intrauterine-insemination group and in the group treated with superovulation and intracervical insemination were nearly twice as likely to conceive as those in the intracervical-insemination group.

CONCLUSIONS

Among infertile couples, treatment with induction of superovulation and intrauterine insemination is three times as likely to result in pregnancy as is intracervical insemination and twice as likely to result in pregnancy as is treatment with either superovulation and intracervical insemination or intrauterine insemination alone.

The Yugoslavia Prospective Study of environmental lead exposure

The Yugoslavia Prospective Study of environmental lead exposure has studied the associations between exposure to lead and pregnancy outcomes; childhood neuropsychological, behavioral, and physical development; and hematologic, renal, and cardiovascular function. The cohort comprises 577 children born to women recruited at midpregnancy in two towns in Kosovo, Yugoslavia; one town is the site of a lead smelter, refinery, and battery plant and the other is 25 miles away and relatively unexposed. A sample of these children has been followed at 6-month intervals through 7.5 years of age. Blood lead concentrations ranged from 1 to 70 microg/dl. Exposure to lead was not associated with adverse pregnancy outcomes. Exposure was associated with modest decrements in intelligence, small increases in blood pressure, higher risks of proteinuria, small increases in behavior problems, and perturbed hematopoiesis. Only at low level exposures (i.e., <16 microg/dl) were small associations with decreased height found. We discuss methodological problems that may hinder causal interpretation of these data, namely, use of blood lead concentration as an exposure measure, confounding, and town-specific associations. We conclude that while reported associations are small, collectively they lend support to the notion that lead is a toxicant with numerous adverse health effects.

Hyperproduction of erythropoietin in nonanemic lead-exposed children

Lead (Pb) poisoning has numerous effects on the erythropoietic system, but the precise mechanism whereby high dose exposure causes anemia is not entirely clear. We previously reported that Pb exposure is associated with depressed serum erythropoietin (EPO) in pregnant women residing in a Pb mining town and in a nonexposed town in Kosovo, Yugoslavia. In a prospective study, we tested the hypothesis that blood Pb concentration (BPb) may be associated with depressed EPO in children. BPb, hemoglobin (Hgb), and serum EPO were measured at ages 4.5, 6.5, and 9.5 years in 211, 178, and 234 children, respectively. At 4.5 years of age, mean BPbs were 38.9 and 9.0 microg/dl in the exposed and nonexposed towns, respectively; BPbs gradually declined to 28.2 and 6.5 microg/dl, respectively, by age 9.5 years. No differences were found in Hgb at any age. At age 4. 5 years, a positive association between BPb and EPO (beta = 0.21; p = 0.0001), controlled for Hgb, was found. The magnitude of this association declined to 0.11 at age 6.5 years (p = 0.0103) and 0.03 at age 9.5 years (p = 0.39). These results were confirmed using repeated measures analyses. We concluded that in Pb-exposed children, the maintenance of normal Hgb requires hyperproduction of EPO. With advancing age (and continuing exposure), this compensatory mechanism appears to be failing, suggesting a gradual loss of renal endocrine function due to Pb exposure.

Lead exposure and intelligence in 7-year-old children: the Yugoslavia Prospective Study

For a prospective study of lead exposure and early development, we recruited pregnant women from a lead smelter town and from an unexposed town in Yugoslavia and followed their children through 7 years of age. In this paper we consider associations between lifetime lead exposure, estimated by the area under the blood lead (BPb) versus time curve (AUC7), and intelligence, with particular concern for identifying lead's behavioral signature. The Wechsler Intelligence Scales for Children-Version III (WISC-III) was administered to 309 7-year-old children, 261 of whom had complete data on intelligence, blood lead, and relevant sociodemographic covariates (i.e., Home Observation for the Measurement of the Environment (HOME), birth weight, gender, sibship size, and maternal age, ethnicity, intelligence, and education). These showed anticipated associations with 7-year intelligence, explaining 41-4% of the variance in Full Scale, Performance, and Verbal IQ. Before covariate adjustment, AUC7 was unrelated to intelligence; after adjustment, AUC7 explained a significant 2.8%-4.2% of the variance in IQ. After adjustment, a change in lifetime BPb from 10 to 30 micro/dl related to an estimated decrease of 4.3 Full Scale IQ points; estimated decreases for Verbal and Performance IQ were 3.4 and 4.5 points, respectively. AUC7 was significantly and negatively related to three WISC-III factor scores: Freedom from Distractibility, Perceptual Organization, and Verbal Comprehension; the association with Perceptual Organization was the strongest. Consistent with previous studies, the IQ/lead association is small relative to more powerful social factors. Findings offer support for lead's behavioral signature; perceptual-motor skills are significantly more sensitive to lead exposure than are the language-related aspects of intelligence.

Blood lead and blood pressure in young children

We examined associations between blood lead concentration (BPb) and blood pressure in 282 children age 5.5 years, residing in an exposed or unexposed town in Kosovo, Yugoslavia. Mean BPb in the exposed town was 37.3 micrograms per dl (standard deviation = 12.0 micrograms per dl) and in the unexposed town was 8.7 micrograms per dl (standard deviation = 2.8 micrograms per dl). After adjustment, a 10 micrograms per dl increase in BPb was associated with a 0.5 (95% CL = -0.2, 1.3) mmHg increase in systolic and a 0.4 (95%, CL = -0.1, 0.9) mmHg increase in diastolic blood pressure. These associations, although compatible with no relation, are similar to those observed in adults; and the data are most consistent with a small association between BPb and blood pressure.

Biological monitoring of workers' exposure to bromine

The use of serum bromine concentration (SeBr) as a measure of exposure was examined in an occupational cohort. Associations with work site, department type, chemical handling, and occupation, as proxy measures of exposure, were studied. SeBr was associated with all of these measures. SeBr was also associated with various demographic characteristics (age, country of origin, and education) in men. In women, there was no association between SeBr and age, country of origin, or education. The use of SeBr as a measure of exposure is discussed. The conclusion is that the exposure to bromine can be assessed by regular monitoring of SeBr.

Fracture after cardiac transplantation: a prospective longitudinal study

Cardiac transplantation is associated with increased prevalence of vertebral fractures, but the natural history of and risk factors for fracture after this life-saving procedure are unclear. We evaluated 47 patients (34 men and 13 postmenopausal women) before transplantation with spinal radiographs, determination of bone density by dual energy x-ray absorptiometry, and measurement of biochemical indexes of mineral metabolism. During the first year after transplantation, incident fractures were documented radiographically. Associations among demographic characteristics, bone density, biochemistries, and fracture risk were evaluated with logistic regression analysis. Despite supplementation with elemental calcium (1000 mg/day) and vitamin D (400 IU/day), 17 patients (7 women and 10 men) sustained a total of 34 fractures. Most fractures involved the spine, and 85% of the patients who experienced fracture did so within 6 months of transplantation. Fifty-four percent of the women and 29% of the men experienced fracture. Femoral neck bone mineral density was significantly lower in women who experienced fracture than in those who did not (0.604 +/- 0.11 vs. 0.760 +/- 0.12 g/cm2; P < 0.04), but did not differ in men according to fracture outcome. The amount of bone loss at the femoral neck by 6 months after transplantation was significantly greater in men with fracture than in men without fracture (12.0 +/- 6.4% vs. 6.8 +/- 5.3%; P < 0.04), but did not differ in women according to fracture outcome. Pretransplant 1,25-dihydroxyvitamin D levels were significantly lower (25 +/- 9 vs. 39 +/- 17 pg/mL; P < 0.007) and intact PTH levels tended to be higher in men who did not experience fracture (37 +/- 15 vs. 69 +/- 46 pg/mL; P < 0.06). Individual pretransplant bone density measurements demonstrated substantial overlap between patients who did and did not experience fracture, and normal bone density did not necessarily protect against fracture after transplantation. We conclude that fractures are a common and early complication of cardiac transplantation. No pretransplant measurement has yet been identified that reliably predicts fracture after transplantation in the individual patient.

Consequences of lead exposure and iron supplementation on childhood development at age 4 years

For a prospective study of lead exposure and early development, we recruited pregnant women from a smelter town and a nonlead-exposed town in Yugoslavia and followed them and their children through age 4. For 332 children seen at age 4, mean scores on the McCarthy Scales General Cognitive Index (GCI) in the exposed and nonexposed towns were 81.3 and 86.6, respectively; geometric mean blood lead concentrations (BPb) were 39.9 and 9.6 micrograms/dl, respectively. Potential confounders included the quality of the HOME environment; maternal age, intelligence, education, and language; birthweight and gender. These showed predictable associations with 4-year intelligence, accounting for 42.7% of the variance in GCI. Following adjustment for these variables and for concurrent Hgb, we found significant independent adverse associations between GCI and BPb's, measured at 6-month intervals since birth. At age 4, BPb accounted for an incremental 3.5% of the variance in GCI, such that the estimated loss in GCI associated with an increase in BPb from 10-25 micrograms/dl was 3.8 points. The Perceptual-Performance subscale of the McCarthy was most sensitive to Pb exposure, a result consistent with findings from prospective studies in Boston and Port Pirie.

Increased risk of proteinuria among a cohort of lead-exposed pregnant women

Long-term exposure to high concentrations of lead results in renal dysfunction. During a prospective study of environmental lead and pregnancy outcomes in 1502 women residing in two towns in Yugoslavia, we explored whether moderate exposure to lead results in increased rates of proteinuria. The geometric mean blood lead concentrations (BPb) were 17.1 and 5.1 micrograms/dl in the smelter and nonexposed towns, respectively. Increases in BPb were associated with increased odds ratios for both trace and > or = 1+ proteinuria, measured using a urinary dipstick. Comparing the women in the upper 10th percentile of exposure to those in the lowest 10th percentile, the adjusted odds ratio for > or = 1+ proteinuria was 4.5 (95% CI 1.5, 13.6). Similarly, the adjusted odds ratio for trace proteinuria was 2.3 (95% CI 1.3, 4.1). Similar to other studies showing associations between chronic exposure to lead and renal dysfunction, our data suggest that long-term exposure to environmental lead may be associated with proteinuria.

Independent effects of lead exposure and iron deficiency anemia on developmental outcome at age 2 years

For a prospective study of lead exposure, iron status, and infant development, we recruited infants living in a smelter town and a non-lead-exposed town in Kosovo, Yugoslavia. Among 392 infants assessed at age 2 years, the mean Mental Development Index (MDI), Bayley Scales of Infant Development, was 105.2. At age 2 years, geometric mean blood lead concentrations were 35.5 and 8.4 micrograms/dl, respectively, among infants from the exposed and nonexposed towns. After controlling for variables associated with MDI, we found significant independent associations for both blood lead and hemoglobin concentrations. For example, a rise in blood lead concentration at age 2 years from 10 to 30 micrograms/dl was associated with an estimated 2.5 point decrement in MDI (p = 0.03); statistically nonsignificant decrements were associated with blood lead levels measured at birth and at 6, 12, and 18 months of age. A decrease in hemoglobin concentration at 18 months of age from 12 to 10 gm/dl was associated with an estimated 3.4 point decrement in MDI (p = 0.02); the latter association was present in both towns, suggesting that it was due to iron deficiency anemia independent of lead exposure. The findings suggest that the brain is vulnerable to the effects of both lead exposure and anemia before 2 years of age. On a global basis, the developmental consequences of anemia may exceed those of lead exposure.

Depressed serum erythropoietin in pregnant women with elevated blood lead

During the course of a prospective study of lead exposure and pregnancy outcome in 1,502 women, we tested the hypothesis that environmental lead exposure is associated with depressed serum erythropoietin concentration. At mid-pregnancy and at delivery, blood samples were stratified by hemoglobin concentration; within each hemoglobin stratum, sera of women with the lowest and highest whole blood lead concentrations were selected for serum erythropoietin analysis. Analysis of variance revealed that women with higher blood lead levels had inappropriately low serum erythropoietin at both mid-pregnancy and at delivery. Thus, depressed serum erythropoietin appears to indicate lead nephrotoxicity, and it may also be responsible for the anemia associated with lead poisoning.

A prospective study of birthweight and length of gestation in a population surrounding a lead smelter in Kosovo, Yugoslavia

This paper tests the hypothesis that exposure to lead during pregnancy is associated with reduced intrauterine growth and an increase in preterm delivery. The sample comprises women, recruited at mid-pregnancy, residing in Titova Mitrovica, a lead smelter town, or in Pristina, a non-exposed town 25 miles away. Both towns are in the province of Kosovo, Yugoslavia. Mean blood lead concentrations (BPb's) at mid-pregnancy were 0.92 mumol/L (+/- 0.38, N = 401) in the exposed town and 0.27 mumol/L (+/- 0.09, N = 506) in the comparison town. No differences were found between towns for either birthweight or length of gestation. Mean birthweight was 3308 (+/- 566) grams in Titova Mitrovica and 3361 (+/- 525) grams in Pristina. Mean length of gestation was 274 (+/- 18.8) days in Titova Mitrovica and 275 (+/- 15.6) days in Pristina. After adjustment for the effects of potential confounders, no significant relationships were found between maternal BPb measured at mid-pregnancy, at delivery or in the umbilical cord and either birthweight, length of gestation, or preterm delivery (less than 37 weeks). We conclude that exposure to environmental lead does not impair fetal growth or influence length of gestation.

Determinants of elevated blood lead during pregnancy in a population surrounding a lead smelter in Kosovo, Yugoslavia

We are prospectively examining the relation between environmental lead exposure and pregnancy outcome in cohorts of women exposed to a wide range of air lead concentrations. Titova Mitrovica, Yugoslavia, is the site of a large lead smelter, refinery, and battery factory. At midpregnancy, 602 women in T. Mitrovica and 900 women in Pristina, a non-lead-exposed control town, were interviewed. Blood was obtained for blood lead (PbB), hemoglobin, erythrocyte protoporphyrin, and serum ferritin measurements. Women were seen again at delivery, at which time maternal and umbilical cord blood samples were obtained. While many demographic and social characteristics were similar across the two towns, women in Pristina were more likely to report employment outside the home, cigarette smoking, and alcohol use during pregnancy. As expected, PbB levels were substantially higher in the smelter town. At midpregnancy, PbB geometric means were 17.1 micrograms/dL in T. Mitrovica and 5.1 micrograms/dL in Pristina; 86% of the pregnant women in T. Mitrovica, compared to 3.4% of those in Pristina, had PbB levels greater than 10 micrograms/dL. Within T. Mitrovica, distance between the home and the smelter was the most important predictor of PbB at mid-pregnancy and delivery. Husband's employment in the lead industry was associated with a significant increase in maternal PbB levels independent of place of residence. Higher maternal serum ferritin concentrations were associated with lower PbB levels, suggesting that dietary iron inhibits lead absorption. Overall, the placenta was a poor barrier to lead; the relationship between maternal PbB and umbilical cord PbB was linear across a wide range of PbB levels.

Procedure-specific costs and savings in a mandatory program for second opinion on surgery

Initial examination of the surgery experience of participants in a large employer-sponsored second opinion program revealed minimal savings in medical resource costs. But closer examination of relative savings for specific procedure categories showed that the greatest savings are for high-cost procedures: hysterectomy, prostatectomy, back surgery, and hip replacement. Furthermore, a nonconfirming second opinion does not dissuade patients from some procedures. Decisions about which procedures to include in a mandatory program should consider volume, costs, and effects of nonconfirmation, as well as the advantages of a mandatory second opinion for skeptical patients, or for patients for whom a controversial procedure has been recommended.

Past pregnancy outcomes among women living in the vicinity of a lead smelter in Kosovo, Yugoslavia

This analysis compares the rates of spontaneous abortion among women living in the vicinity of a lead smelter with those of women living in a town where blood lead levels were low. Data derive from the obstetric histories of both groups of women obtained while seeking prenatal care for a later pregnancy. A total of 639 women (304 exposed, 335 unexposed) had at least one previous pregnancy and lived at the same address since their first pregnancy. The geometric mean blood lead concentrations in the sample at the time of the interviews were 0.77 mumol/L in the exposed town and 0.25 mumol/L in the unexposed town. The rates of spontaneous abortions in first pregnancies were similar, with 16.4 percent of women in the exposed town and 14.0 percent in the unexposed town reporting loss. The adjusted odds ratio relating town of residence to spontaneous abortion was 1.1 (95% CI = 0.9, 1.4). This analysis represents the first systematic attempt to seek an association between environmental lead exposure and spontaneous abortion. As such, the failure to find a positive association strongly suggests that at the levels of exposure represented in our sample, such an association does not exist.