Howard J. Hoffman

Medical, psychosocial, and behavioral risk factors do not explain the increased risk for low birth weight among black women☆☆☆★★★

OBJECTIVE Our purpose was to determine whether various demographic, behavioral, housing, psychosocial, or medical characteristics explain the difference in pregnancy outcome between black and white women. STUDY DESIGN A sample of 1491 multiparous women with singleton pregnancies, 69% of whom were black and 31% of whom were white and who enrolled for care between Oct. 1, 1985, and March 30, 1988, participated in the study. The frequencies of various demographic, medical environmental, and psychosocial risk factors among black and white women were determined. The outcome measures were birth weight, gestational age, fetal growth restriction, preterm delivery and low birth weight. RESULTS White infants were heavier and born later than black infants. The white women in this sample smoked more cigarettes, moved more frequently, and had worse psychosocial scores. The black women had lower incomes, were less likely to be married, and had more hypertension, anemia, and diabetes. Besides race, only maternal height, weight, blood pressure, diabetes, and smoking had a consistent impact on outcome and did not explain the difference in outcome between the two groups. CONCLUSION In this low-income population, many of the risk factors for low birth weight were more common among white women than black women. Nevertheless, black women had more infants born preterm, with growth restriction, and with low birth weight than did white women. The various maternal characteristics studied did not explain these differences.

Intrauterine growth retardation and preterm delivery: prenatal risk factors in an indigent population

Prenatally ascertained risk factors for low birth weight were evaluated in a population of 17,000 indigent women for their specific effect on intrauterine growth retardation and on the rate of preterm delivery. In a univariate analysis, intrauterine growth retardation occurred more frequently in women who were black, single, primiparous, less than 17 or greater than 30 years old, short, thin, had a previous preterm delivery, consumed alcohol, took drugs, or gained limited weight. Preterm delivery occurred significantly more frequently in women who were black, single, thin, less than 17 or greater than 30 years old, had less than a twelfth grade education, or gained limited weight. In logistic regression analyses, race, parity, maternal age, a history of preterm delivery, smoking, short stature, low weight, and low weight gain remained significant risk factors of intrauterine growth retardation. Of these factors, smoking, short stature, low weight, and low weight gain showed the greatest correlation. Factors significantly related to preterm delivery included black race, single marital status, younger or older ages, previous preterm delivery, smoking, low weight, and very low or high weight gain. A previous preterm delivery and very low maternal weight had the greatest correlation. Identification of specific risk factors of both intrauterine growth retardation and preterm delivery should aid in the development of strategies to reduce the prevalence of these conditions.

Smoking, maternal age, fetal growth, and gestational age at delivery

The relationship between smoking and maternal age and their combined effects on birth weight, intrauterine growth retardation, and preterm delivery were studied. Smoking lowers birth weight both by decreasing fetal growth and by lowering gestational age at delivery. However, the effect of smoking on both fetal growth and gestational age is significantly greater as maternal age advances. In a multiple logistic regression model adjusting for race, parity, marital status, maternal weight, weight gain, and alcohol use, smoking was associated with a fivefold increased risk of growth retardation in women older than 35 but less than a twofold increased risk in women younger than 17. Smoking reduced birth weight by 134 gm in young women but 301 gm in women older than 35. Smoking in older women also was associated with more instances of preterm delivery and a lower mean gestational age when compared to women 25 or younger.

The Effect of Cigarette Smoking on Neonatal Anthropometric Measurements

Objective To estimate the effect of maternal cigarette smoking on birth weight, crown-heel length, and ten other neonatal anthropometric measurements. Methods Data are from a cohort study on risk factors for fetal growth retardation (FGR) in multiparous women conducted from December 1985 through October 1988. Information on smoking status was collected four times during pregnancy. Data analysis included 1205 singleton infants of women delivering at term. Neonatal anthropometric measurements were obtained within 48 hours of birth, including birth weight, crown-heel length, ponderal index, head and abdominal circumferences, arm length and circumference, femur length and thigh circumference, and triceps, thigh, and subscapular skinfold measurements. Analysis of covariance models were used to assess the independent effect of smoking on each neonatal measurement. Results Neonates born to women who reported smoking during the first trimester had a 0.6–1.9% reduction in most neonatal anthropometric measurements, resulting in an overall reduction of birth weight of 130 g (4%). Neonates born to women who continued to smoke throughout pregnancy had an average adjusted reduction in birth weight of 189 g (5.9%), compared with a 55 g (1.7%) reduction for neonates born to women who stopped smoking after the first trimester. For women who continued to smoke throughout pregnancy, an increased number of cigarettes smoked was associated with increased reductions in birth weight and neonatal chest and abdominal circumferences. For women who stopped smoking after the first trimester, stopping was a better predictor of neonatal anthropometric measurements than the number of cigarettes smoked early in pregnancy. Conclusions Except for the ponderal index, all neonatal anthropometric measurements studied showed some negative effect of maternal cigarette smoking. Head circumference is the measurement least reduced. Smoking cessation is a better predictor of infant size than the number of cigarettes smoked in the first trimester.

Intrauterine growth retardation: Standards for diagnosis

Abstract An intrauterine growth-retarded infant is commonly defined as one weighing less than the 10th percentile in birth weight for its gestational age. However, because there is no standard population from which to derive these percentiles, the birth weights that serve as the cutoff point in various published studies may differ by several hundred grams at any gestational age. For this reason, we examined the studies from which the currently used 10th-percentile standards are derived to determine which factors may be responsible for the variation. In addition to obvious differences in the populations and geographic areas on which they were based, studies differed in how gestational age was determined, whether the gestational age was “rounded” or given in completed weeks, which types of infants were excluded, whether the studies were hospital or population based, and whether they were controlled for sex of the infant and race and parity of the mother. These differences in study methodology may be as or more important than the population differences in defining the 10th percentile cutoffs. A single national standard for intrauterine growth retardation would allow comparison between studies of risk factors, diagnostic tests, management, and long-term follow-up status of fetuses and infants with intrauterine growth retardation.

Pre-pregnancy risk factors of small-for-gestational age births among parous women in Scandinavia

To study the etiology and consequences of intrauterine growth retardation (IUGR), a prospective study was organized by the National Institute of Child Health and Human Development, NIH, with the Universities of Trondheim and Bergen in Norway, Uppsala in Sweden, and Alabama in the United States. This paper reports on the Scandinavian portion of the study. 6,354 women were referred to the study and 5,722 women, who were expecting their second or third child between January 1986 and March 1988, were eligible and made their first appointment for the study. Of these, 1,945 women and their births were selected for follow‐up at four prenatal visits, delivery, and during the first year of life. This report analyzes the relative impact of various maternal pre‐pregnancy risk factors associated with SGA birth. For example, mothers who smoked cigarettes around the time of conception, but who had none of the other major risk factors, nearly doubled their risk of SGA birth. A previous low birth weight (LBW) delivery increased the risk nearly two and a half times among non‐smokers. If a mother both smoked and had a previous LBW, the relative risk rose to nearly five and a half. Low maternal pre‐pregnancy weight (> 50 kg) increased the risk of SGA birth almost twofold among non‐smokers, while low pre‐pregnancy weight and smoking together increased the risk of SGA birth fourfold. A low weight mother who smoked and also had a previous LBW delivery, had a risk of SGA birth that was nearly six times that of a mother without those characteristics.

Hearing Impairment Associated With Depression in US Adults, National Health and Nutrition Examination Survey 2005-2010

IMPORTANCE Depression among hearing impaired US adults has not been studied previously. OBJECTIVE To estimate the prevalence of and risk factors for depression among adults with hearing loss. DESIGN, SETTING, AND PARTICIPANTS Adults aged 18 years or older (N = 18 318) who participated in the National Health and Nutrition Examination Survey (NHANES), 2005-2010, a nationally representative sample. INTERVENTIONS Multistage probability sampling of US population. MAIN OUTCOMES AND MEASURES Depression, assessed by the 9-item Patient Health Questionnaire (PHQ-9) scale, and hearing impairment (HI), assessed by self-report and audiometric examination for adults aged 70 years or older. RESULTS The prevalence of moderate to severe depression (PHQ-9 score, ≥10) was 4.9% for individuals reporting excellent hearing, 7.1% for those with good hearing, and 11.4% for participants who reported a little trouble or greater HI. Using excellent hearing as the reference, after adjusting for all covariates, multivariate odds ratios (ORs) for depression were 1.4 (95% CI, 1.1-1.8) for good hearing, 1.7 (1.3-2.2) for a little trouble, 2.4 (1.7-3.2) for moderate trouble, 1.5 (0.9-2.6) for a lot of trouble, and 0.6 (0.1-2.6) for deaf. Moderate HI (defined by better ear pure-tone average of hearing thresholds at 0.5, 1, 2, and 4 kHz within the range 35- to 49-dB hearing level) was significantly associated with depression among older women (OR, 3.9; 95% CI, 1.3-11.3), after adjusting for age, sex, race/ethnicity, lifestyle characteristics, and selected health conditions. CONCLUSIONS AND RELEVANCE After accounting for health conditions and other factors, including trouble seeing, self-reported HI and audiometrically determined HI were significantly associated with depression, particularly in women. Health care professionals should be aware of an increased risk for depression among adults with hearing loss.

Spectral Analysis Assessment of Respiratory Sinus Arrhythmia in Normal Infants and Infants Who Subsequently Died of Sudden Infant Death Syndrome

ABSTRACT: Reduced heart rate variability has been found in infants who later succumb to the sudden infant death syndrome (SIDS). To determine whether respiratory sinus arrhythmia, a major component of heart rate variability, is also reduced in SIDS victims, nighttime portions of eighteen 24-h recordings of ECG and respiration from infants who later died of SIDS and 52 recordings from control infants were assessed using spectral analysis. Two aspects of respiratory sinus arrhythmia were examined: “extent” (the absolute heart rate variation at the respiratory frequency) and “coherence” (the degree to which heart rate follows respiration regardless of the absolute amount of variation). Respiratory parameters were used to classify each 1-min epoch as quiet sleep, rapid eye movement sleep, waking, or indeterminate state. Median extent and coherence values across the night were then computed for each sleep-waking state. Two-way (group × state) repeated measures analysis of variance tests were then used to compare respiratory sinus arrhythmia values for 13 SIDS victims and 13 control infants matched by postnatal age, birth weight, sex, and gestational age. Extent of respiratory sinus arrhythmia was significantly lower in the SIDS victims across all sleep-waking states, a finding that persisted after adjusting for heart rate. Coherence values did not differ significantly. These results suggest that even before the time of maximal risk for the syndrome, SIDS victims, as a group, differ from controls in the extent to which cardiac and respiratory activity couple, and this difference is independent of basal heart rate.

Use of a dummy (pacifier) during sleep and risk of sudden infant death syndrome (SIDS) : population based case-control study

Abstract Objectives To examine the association between use of a dummy (pacifier) during sleep and the risk of sudden infant death syndrome (SIDS) in relation to other risk factors. Design Population based case-control study. Setting Eleven counties in California. Participants Mothers or carers of 185 infants whose deaths were attributed to SIDS and 312 randomly selected controls matched for race or ethnicity and age. Main outcome measure Use of a dummy during sleep determined through interviews. Results The adjusted odds ratio for SIDS associated with using a dummy during the last sleep was 0.08 (95% confidence interval 0.03 to 0.21). Use was associated with a reduction in risk in every category of sociodemographic characteristics and risk factors examined. The reduced risk associated with use seemed to be greater with adverse sleep conditions (such as sleeping prone or on side and sleeping with a mother who smoked), although the observed interactions were not significant. In addition, use of a dummy may reduce the impact of other risk factors for SIDS, especially those related to adverse sleep environment. For example, infants who did not use a dummy and slept prone or on their sides (v on their back) had an increased risk of SIDS (2.61, 1.56 to 4.38). In infants who used dummies, there was no increased risk associated with sleeping position (0.66, 0.12 to 3.59). While cosleeping with a mother who smoked was also associated with increased risk of SIDS among infants who did not use a dummy (4.5, 1.3 to 15.1), there was no such association among those who did (1.1, 0.1 to 13.4). Conclusions Use of a dummy seems to reduce the risk of SIDS and possibly reduces the influence of known risk factors in the sleep environment.

Cognitive development of term small for gestational age children at five years of age

AIM To assess the relative significance for cognitive development of small for gestational age, parental demographic factors, and factors related to the child rearing environment. METHODS IQ of a population based cohort of 338 term infants who were small for gestational age (SGA) and without major handicap, and a random control sample of 335 appropriate for gestational age (AGA) infants were compared at 5 years of age. RESULTS The mean non-verbal IQ was four points lower, while the mean verbal IQ was three points lower for the children in the SGA group. The results were not confounded by parental demographic or child rearing factors. However, parental factors, including maternal non-verbal problem solving abilities, and child rearing style, accounted for 20% of the variance in non-verbal IQ, while SGA versus AGA status accounted for only 2%. The comparable numbers for verbal IQ were 30 and 1%. Furthermore, we found no evidence that the cognitive development of SGA children was more sensitive to a non-optimal child rearing environment than that of AGA children. Maternal smoking at conception was associated with a reduction in mean IQ comparable to that found for SGA status, and this effect was the same for SGA and AGA children. The cognitive function of asymmetric SGA was comparable to that of symmetric SGA children. CONCLUSIONS Our findings indicate that child cognitive development is strongly associated with parental factors, but only marginally associated with intrauterine growth retardation.