Does inadequate diet during childhood explain the higher high fracture rates in the Southern United States?

SUMMARY: Southern states have the highest age-adjusted hip fracture rates among older adults in the United States. Regional hip fracture rates in the United States in 1986-1993 correlate with death rates from rickets in the 1940s. Historical patterns of bone nutrition early in life might explain contemporary geographic patterns in bone fragility. INTRODUCTION: State of residence early in life is a better predictor of the risk of hip fracture after age 65 than state of current residence. Therefore, the geography of rickets mortality in the United States before 1950 was compared with the geography of hip fracture rates among older adults in the United States during 1986-1993. METHODS: Vital statistics data for the US white population for 1942-1948 allowed calculation of the ratio of deaths from rickets to live births for each geographic division of the USA. These ratios were correlated with previously published, standardized hip fracture rates among whites 65-89 years old during 1986-1993 by census division. RESULTS: During 1942-1948, the rickets mortality ratio among whites was 3.11 in the South, 1.91 in the Northeast, 1.75 in the Midwest, and 1.04 in the West. The correlation of mortality with risk of hip fracture was 0.71 (p = 0.03) for both sexes combined and 0.86 (p = 0.01) for women. CONCLUSIONS: Inadequate nutrition during skeletal formation early in life might explain the higher incidence of hip fracture among older adults in the South.

Self-reported falls and fall-related injuries among persons aged>or=65 years--United States, 2006.

PROBLEM: In 2005, 15,802 persons aged>or=65 years died from fall injuries. How many older adults seek outpatient treatment for minor or moderate fall injuries is unknown. METHOD: To estimate the percentage of older adults who fell during the preceding three months, the Centers for Disease Control and Prevention (CDC) analyzed data from two questions about falls included in the 2006 Behavioral Risk Factor Surveillance System (BRFSS) survey. RESULTS: Approximately 5.8 million (15.9%) persons aged>or=65 years reported falling at least once during the preceding three months, and 1.8 million (31.3%) of those who fell sustained an injury that resulted in a doctor visit or restricted activity for at least one day. DISCUSSION: This report presents the first national estimates of the number and proportion of persons reporting fall-related injuries associated with either doctor visits or restricted activity. SUMMARY: The prevalence of falls reinforces the need for broader use of scientifically proven fall-prevention interventions. IMPACT ON INDUSTRY: Falls and fall-related injuries represent an enormous burden to individuals, society, and to our health care system. Because the U.S. population is aging, this problem will increase unless we take preventive action by broadly implementing evidence-based fall prevention programs. Such programs could appreciably decrease the incidence and health care costs of fall injuries, as well as greatly improve the quality of life for older adults.

United States pedestrian fatality rates by vehicle type.

OBJECTIVE: To describe the relation between motor vehicle type and the risk of fatally injuring a pedestrian. DESIGN: The risk of killing a pedestrian was measured as the number of pedestrian fatalities per billion miles of vehicle travel by each vehicle type in the US in 2002 as reported by the National Highway Traffic Safety Administration's Fatality Analysis Reporting System. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Rates for each vehicle type by sex, age, and rural/urban roadway type and rate comparisons using relative risks (RR) and 95% confidence intervals (CIs). RESULTS: Passenger cars and light trucks (vans, pickups, and sport utility vehicles) accounted for 46.1% and 39.1%, respectively, of the 4875 deaths, with the remainder split among motorcycles, buses, and heavy trucks. Compared with cars, the RR of killing a pedestrian per vehicle mile was 7.97 (95% CI 6.33 to 10.04) for buses; 1.93 (95% CI 1.30 to 2.86) for motorcycles; 1.45 (95% CI 1.37 to 1.55) for light trucks, and 0.96 (95% CI 0.79 to 1.18) for heavy trucks. Compared with cars, buses were 11.85 times (95% CI 6.07 to 23.12) and motorcycles were 3.77 times (95% CI 1.40 to 10.20) more likely per mile to kill children 0-14 years old. Buses were 16.70 times (95% CI 7.30 to 38.19) more likely to kill adults age 85 or older than were cars. The risk of killing a pedestrian per vehicle mile traveled in an urban area was 1.57 times (95% CI 1.47 to 1.67) the risk in a rural area. CONCLUSIONS: Outcomes reflect the ways in which a vehicle's characteristics (mass, front end design, and visibility) and its degree of interaction with pedestrians affect its risk per mile. Modifications in vehicle design might reduce pedestrian injury. The greatest impact on overall US pedestrian mortality will result from reducing the risk from the light truck category.

CDC's National Violent Death Reporting System: background and methodology.

OBJECTIVES: This paper describes a new surveillance system called the National Violent Death Reporting System (NVDRS), initiated by the United States Centers for Disease Control and Prevention. NVDRS's mission is the collection of detailed, timely information on all violent deaths. DESIGN: NVDRS is a population based, active surveillance system designed to obtain a complete census of all resident and occurrent violent deaths. Each state collects information on its own deaths from death certificates, medical examiner/coroner files, law enforcement records, and crime laboratories. Deaths occurring in the same incident are linked. Over 270 data elements can be collected on each incident. SETTING: The 13 state health departments of Alaska, Colorado, Georgia, Maryland, Massachusetts, New Jersey, North Carolina, Oklahoma, Oregon, Rhode Island, South Carolina, Virginia, and Wisconsin. SUBJECTS: Cases consist of violent deaths from suicide, homicide, undetermined intent, legal intervention, and unintentional firearm injury. Information is collected on suspects as well as victims. INTERVENTIONS: None. OUTCOME MEASURES: The quality of surveillance will be measured in terms of its acceptability, accuracy, sensitivity, timeliness, utility, and cost. RESULTS: The system has just been started. There are no results as yet. CONCLUSIONS: NVDRS has achieved enough support to begin data collection efforts in selected states. This system will need to overcome the significant barriers to such a large data collection effort. Its success depends on the use of its data to inform and assess violence prevention efforts. If successful, it will open a new chapter in the use of empirical information to guide public policy around violence in the United States.

Violent attacks on Middle Easterners in the United States during the month following the September 11, 2001 terrorist attacks.

OBJECTIVES: To document and describe hate related violent attacks on Middle Easterners or those perceived to be Middle Easterners during the month following the September 11, 2001 terrorist attacks in New York City and Washington, DC. METHODS: The LexisNexis database of newspaper reports were used to identify incidents of hate related violent acts against Middle Easterners or those perceived to be Middle Easterners in the US between September 1 and October 11, 2001. A total of 100 incidents of hate related violence were identified in the 2659 news articles that were reviewed. RESULTS: Of the 100 incidents of violent victimization that took place during the period September 1 to October 11, only one incident occurred before September 11. The 99 incidents that occurred after September 11 involved at least 128 victims and 171 perpetrators. Most violent victimizations occurred within 10 days of the attacks, involved male perpetrators and male victims, and occurred in convenience stores, on the streets, at gas stations, at schools/colleges, and at places of worship. DISCUSSION: Most violent victimizations occurred in the 10 days immediately following the terrorist attacks indicating that interventions that promote tolerance and understanding of diversity need to be implemented quickly in order to be effective. In addition, patrolling by police and Neighborhood Watch programs around convenience stores and gas stations may also be effective strategies for reducing hate related violent crimes.

Sex differences in the prevalence of human birth defects: a population-based study.

BACKGROUND: Sex differences in the prevalence of several human birth defects have often been reported in the literature, but the extent of sex differences for most birth defects is unknown. To determine the full extent of sex differences in birth defects in a population, we examined population-based data from the Metropolitan Atlanta Congenital Defects Program (MACDP). METHODS: MACDP records were analyzed for 1968 through 1995. We determined the sex-specific prevalence of all major birth defects, using the total number of live births by sex during these years as the denominator. For each specific defect, we calculated a relative risk with regard to sex on the basis of the ratio of prevalence among males to prevalence among females. Male-female relative risks were also determined for total major birth defects and for several broad categories of defects. RESULTS: The overall prevalence of major defects at birth was 3.9% among males and 2.8% among females. All but two of the major categories of birth defects (nervous system defects and endocrine system defects) had a higher prevalence among males. Defects of the sex organs were eight and one-half times more prevalent among males and accounted for about half of the increased risk of birth defects among males relative to females. Urinary tract defects were 62% more prevalent among males, and gastrointestinal tract defects were 55% more prevalent among males. Among specific defect types, twofold or greater differences in prevalence by sex were common. CONCLUSIONS: Our data indicate that sex differences in the prevalence of specific human birth defects are common, and male infants are at greater risk for birth defects than female infants. Several mechanisms have been proposed to account for these differences.

Survival of infants with spina bifida: a population study, 1979-94.

This study aimed to investigate the survival of infants born with spina bifida between 1979 and 1994 from the population-based Metropolitan Atlanta Congenital Defects Program (MACDP) and to identify clinical and demographic factors associated with survival. Survival status was obtained from MACDP records and the National Death Index. Survival rates were calculated using the Kaplan-Meier method. Risk factors potentially associated with survival were examined by the log-rank test. We assessed the independent effect of risk factors using the Cox proportional hazards model. Overall, 78.4% of children with spina bifida survived during the study period. Of the 235 infants born with spina bifida, 87.2% survived the first year of life. Survival to age 1 for the 1979-83, 1984-88 and 1989-94 birth cohorts was 82.7%, 88.5% and 91.0% respectively. In multivariable analysis, factors associated with increased mortality were low birthweight (<2500 g) (vs. > or =2500g, relative risk (RR) 2.3 [95% CI 1.1, 4.9]) and high lesions (vs. low lesions, RR 3.4 [95% CI 1.6, 7.1]). This study suggests a continuous improvement in survival among children born with spina bifida in Atlanta. Demographic and clinical factors are associated with length of survival. This information is useful for both clinicians and families who need to plan for the long-term care of these children.

Surveillance for homicide among intimate partners--United States, 1981-1998.

PROBLEM/CONDITION: A substantial percentage of all homicides in the United States are committed by intimate partners of the victims. Among females, approximately 1 in 3 homicides are intimate partner homicides (IPHs). Intimate partner homicides cannot be tracked by using death certificates because death certificates do not record the victim's relationship to the perpetrator. REPORTING PERIOD COVERED: This report summarizes information regarding IPHs that occurred in the United States during 1981-1998. DESCRIPTION OF THE SYSTEM: This report is based on Supplemental Homicide Reports (SHRs) collected by the Federal Bureau of Investigation (FBI) as part of their Uniform Crime Reporting System. SHRs are filed voluntarily by police departments for homicides occurring within their jurisdiction. SHRs include demographic variables regarding victims and perpetrators, their relationship, and weapon(s) used. Data from the SHR file were weighted by comparison with homicide data from death certificates to compensate for underreporting. IPHs were restricted to victims aged > or = 10 years. RESULTS: The risk for death from IPH among males was 0.62 times the risk among females. However, the rate among black males was 1.16 times the rate among black females. Among racial groups, rates among blacks were highest, and the rates among Asian or Pacific Islanders were lowest. Rates were highest among females aged 20-49 years and among males aged 30-59 years. During the study period, rates among white females decreased 23%, and rates among white males decreased 61.9%. Rates among black females decreased 47.6%, and rates among black males decreased 76.4%. Highest rates occurred in the southern and western states among both white and black females. A graded increase in IPH risk occurred with community population size. Approximately 50% of IPHs were committed by legal spouses and 33% by boyfriends or girlfriends for both male and female victims. IPH rates were less than expected during the months of January, October, and November. INTERPRETATION: Although total homicide rates have fluctuated during 1981-1998, IPH rates have decreased steadily during this period, and among certain subpopulations, the decrease has been substantial. Decreases are temporally associated with the introduction of social programs and legal measures to curb intimate partner violence, but a causal relationship has not been established. Likewise, no confirmed explanation exists for the greater decrease in rates among males compared with rates among females. The differences in IPH rates by race indicate that economic, social, and cultural factors are involved. The analysis by community population size and state demonstrates that regional sociocultural differences might be involved also. Access to firearms might be a key factor in both male and female IPHs. PUBLIC HEALTH ACTIONS: The descriptive epidemiology of IPH is changing rapidly and should continue to be monitored. Understanding the reasons forthe recent decreases in IPHs might help identify methods for primary and secondary prevention and further reduce IPH rates.

Increased risk for developmental disabilities in children who have major birth defects: a population-based study.

OBJECTIVE: We sought to quantify the strength of associations between each of four specific developmental disabilities (DDs) and specific types of major birth defects. METHODS: We linked data from 2 independent surveillance systems, the Metropolitan Atlanta Congenital Defects Program and the Metropolitan Atlanta Developmental Disabilities Surveillance Program. Children with major birth defects (n = 9142; born 1981-1991 in metro Atlanta) and 3- to 10-year-old children who were born between 1981 and 1991 in metro Atlanta and identified between 1991 and 1994 as having mental retardation, cerebral palsy, hearing impairment, or vision impairment (n = 3685) were studied. Prevalence ratio (PR), which is the prevalence of a DD in children with 1 or more major birth defects divided by the prevalence of the same DD in children without major birth defects, was measured. RESULTS: Among the 9142 children who were born with a major birth defect, 657 (7.2%) had a serious DD compared with 0.9% in children with no major birth defect, yielding a PR of 8.3 (95% confidence interval: 7.6-9.0). In general, the more severe the DD, the higher was the PR. Birth defects that originated in the nervous system and chromosomal defects resulted in the highest PRs for a subsequent DD. For all other categories of birth defects, PRs were lowest when all major birth defects present were confined to a single category (ie, isolated defects). PRs for any DD increased monotonically with the number of coded birth defects per child or the number of different birth defect categories per child, regardless of the severity of the defect or whether defects of the nervous system, chromosomal defects, or "other syndromes" were counted. CONCLUSIONS: These data highlight the possible early prenatal origins of some DDs and suggest that both the number of coded birth defects present and the number of anatomic systems involved are strongly related to functional outcomes.

Continued occurrence of Accutane-exposed pregnancies.

BACKGROUND: Accutane a teratogenic prescription drug licensed to treat severe, recalcitrant nodular acne. First-trimester pregnancy exposure can cause major birth defects. The manufacturer began a Pregnancy Prevention Program (PPP) in 1988; however, exposed pregnancies continue to occur. In 1996, the manufacturer began a direct-to-consumer advertising campaign, raising concerns of more exposed pregnancies. METHODS: We examined trends in Accutane use by reproductive-aged women. We also interviewed a series of 14 women in California who had recent Accutane-exposed pregnancies to identify opportunities for prevention. RESULTS: The estimated number of Accutane prescriptions for reproductive-aged women has more than doubled in the past 10 years; it is the most widely used teratogenic drug in the United States, with approximately 2.5 per 1,000 reproductive-aged women exposed to Accutane in 1999. One-half of the women interviewed reported seeing an advertisement for prescription acne treatment before taking Accutane. Eight of the 14 women used no contraception at the time of the exposed pregnancy; 13 of the 14 women did not use two forms of contraception. Four of the 14 women did not have pregnancy tests before starting Accutane. None reported seeing all PPP components, and four saw only the information on the pill packet. These 14 pregnancies resulted in four live infants who had no apparent birth defects, one live-born infant with multiple defects, four spontaneous abortions, and five induced abortions. CONCLUSIONS: The increase in Accutane use observed among females may be exacerbated by advertising. Physicians and patients must use more caution with teratogenic prescription drugs. Published 2001 Wiley-Liss, Inc.

Impact of folic acid fortification of the US food supply on the occurrence of neural tube defects.

CONTEXT: Daily consumption of 400 microg of folic acid before conception and during early pregnancy dramatically reduces the occurrence of neural tube defects (NTDs). Before food fortification, however, only an estimated 29% of US reproductive-aged women were taking a supplement containing 400 microg of folic acid daily. The US Food and Drug Administration authorized addition of folic acid to enriched grain products in March 1996, with compliance mandatory by January 1998. OBJECTIVE: To evaluate the impact of food fortification with folic acid on NTD birth prevalence. DESIGN, SETTING, AND POPULATION: National study of birth certificate data for live births to women in 45 US states and Washington, DC, between January 1990 and December 1999. MAIN OUTCOME MEASURE: Birth certificate reports of spina bifida and anencephaly before fortification (October 1995 through December 1996) compared with after mandatory fortification (October 1998 through December 1999). RESULTS: The birth prevalence of NTDs reported on birth certificates decreased from 37.8 per 100 000 live births before fortification to 30.5 per 100 000 live births conceived after mandatory folic acid fortification, representing a 19% decline (prevalence ratio [PR], 0.81; 95% confidence interval [CI], 0.75-0.87). During the same period, NTD birth prevalence declined from 53.4 per 100 000 to 46.5 per 100 000 (PR, 0.87; 95% CI, 0.64-1.18) for women who received only third-trimester or no prenatal care. CONCLUSIONS: A 19% reduction in NTD birth prevalence occurred following folic acid fortification of the US food supply. However, factors other than fortification may have contributed to this decline.

Risk for birth defects among premature infants: a population-based study.

OBJECTIVE: To investigate the relationship between prematurity and birth defects. STUDY DESIGN: In a population-based cohort study, infants with birth defects were ascertained through the Metropolitan Atlanta Congenital Defects Program, a surveillance system with active methods of ascertainment. Gestational age data were obtained from birth certificates of liveborn, singleton infants with and without birth defects born in the 5-county metropolitan Atlanta area. RESULTS: Among 264,392 infants with known gestational ages born between 1989 and 1995, 7738 were identified as having birth defects (2.93%). Premature infants (<37 weeks' gestation) were more than two times as likely to have birth defects than term infants (37-41 weeks) (risk ratio = 2.43; 95% CI 2.30-2.56). This relationship was evident for several categories of birth defects. The rate of birth defects varied by gestational age categories, with the highest risk in the 29- to 32-week gestational age category (risk ratio = 3.37). CONCLUSIONS: The risk for birth defects is increased in premature infants. Awareness of this relationship is important for clinicians caring for premature infants. The morbidity and mortality associated with a particular defect may be significantly altered by the presence of prematurity. Further study of this association may provide insight into the etiology of these relatively common problems.

The relation between small size for gestational age and the sex ratio of children with birth defects.

BACKGROUND: Infants with birth defects are more likely to be born small for gestational age (SGA) than are other infants. This study describes a relation noted between the percentage SGA and the percentage male among children with various defect types. The data source was case records collected by the Metropolitan Atlanta Congenital Defects Program, a population-based, active surveillance system, during 1968 through 1998. METHODS: The study calculated the correlation between the percentage male and the percentage SGA for isolated cases of 44 different defect types for male-dominant and female-dominant defects separately. RESULTS: The correlation coefficient was -0.47 (P < 0.01) for male-dominant defects and 0.20 (P > 0.05) for female-dominant defects. Male-dominant defects were more likely to show less than 15% SGA and more likely to show the strongest risk differences by sex. CONCLUSIONS: These results are consistent with genetic causation of strongly skewed sex ratios, at least among male-dominant defects. Review of the literature suggests that defects with sex ratios closer to 1 are likely to have lower recurrence risks and therefore are less likely to be inherited than are other defects with skewed sex ratios. Sex ratios closer to 1 and a high percentage SGA may be markers of acquired or environmental birth defects.

Maternal smoking and birth defects: validity of birth certificate data for effect estimation.

OBJECTIVES: The authors sought to assess the validity of birth certificate data for estimating the association between maternal smoking and birth defects. The US standard birth certificate includes check boxes for maternal smoking and for 21 congenital anomalies. The sensitivity and specificity of birth certificate data have been studied, but previous studies have not addressed the validity of these data for estimating the association between birth defects and maternal smoking or other risk factors. METHODS: US public-use natality data (1997-1998) were used to calculate the prevalence ratio (adjusted for maternal age, race/ethnicity, and education) for the association between maternal smoking and 13 defects/defect categories. All analyses were restricted to 45 states, New York City, and the District of Columbia because they collect both maternal smoking and birth defect data. RESULTS: Maternal smoking was associated with an increased prevalence of hydrocephaly (adjusted prevalence ratio [PR] = 1.24; 95% confidence interval [CI] = 1.08, 1.43), microcephaly (PR 1.47; 95% CI 1.15, 1.88), omphalocele/gastroschisis (PR 1.37; 95% CI 1.22, 1.53), cleft lip/palate (PR 1.35; 95% CI 1.25, 1.45), clubfoot (PR 1.62; 95% CI 1.49, 1.75), and polydactyly/syndactyly/adactyly (PR 1.33; 95% CI 1.23, 1.43 ). Previous studies have indicated an association between maternal smoking and gastroschisis, oral clefts, and clubfoot with effect estimates of similar magnitude to this study. CONCLUSIONS: These findings suggest that birth certificate data may be useful for exploratory or corroborative studies estimating the association between birth defects and some risk factors recorded on birth certificates.

Family history, maternal smoking, and clubfoot: an indication of a gene-environment interaction.

Although epidemiologic studies of some birth defects have suggested a gene-smoking interaction, the possibility of this interaction in clubfoot has not been examined. The authors analyzed risk factors among 346 infants with isolated clubfoot and 3,029 infants without defects from the Atlanta Birth Defects Case-Control Study. All infants were born during 1968-1980, and mothers were interviewed in 1982-1983. The authors examined the family history-smoking interaction as an indication of a gene-environment interaction. They defined "smoking" as smoking any time during the first 3 months of pregnancy and "family history" as having a first-degree relative with clubfoot. Conditional logistic regression (matching variables: race, birth hospital, and birth period) was used to obtain effect estimates. The adjusted odds ratios were 1.34 (95% confidence interval (CI): 1.04, 1.72) for smoking only, 6.52 (95% CI: 2.95, 14.41) for family history only, and 20.30 (95% CI: 7.90, 52.17) for a joint exposure of smoking and family history. The effect estimate for the joint exposure was higher than would be expected under either an additive or a multiplicative model of interaction and showed a statistically significant departure from additivity. This study confirms the importance of familial factors and smoking in the etiology of clubfoot and identifies a potentially important interaction.

Is Helicobacter pylori a cause of infantile hypertrophic pyloric stenosis?

My hypothesis is that infantile hypertrophic pyloric stenosis (IHPS) is caused in some cases by Helicobacter pylori (HP) a bacterium commonly found in the human stomach. IHPS is an idiopathic condition of infancy. It occurs at about 5 weeks of age in 3 per 1000 newborns. Children with IHPS have structurally normal pylori at birth and do not resemble children with congenital anomalies. Some nonspecific evidence (temporal distribution, seasonality, familial clustering, leukocytic infiltrates, and increased risk with bottle feeding) are compatible with an infectious etiology. Some other epidemiologic features of IHPS, such as its strong male predominance, its racial and social class variation, and a possible drop in its incidence, are also features of HP infection. Clinical features of IHPS, such as vomiting, hematemesis, and esophagitis, are also consistent with HP. Finally, children with IHPS appear to be more likely to develop chronic conditions, such as peptic ulcers, now known to be caused by HP.

Evaluation of selected characteristics of pregnancy drug registries.

Given that half of U.S. pregnancies are unintended and some prescription drugs are frequently used by reproductive-age women, there is an increasing interest in establishing pregnancy registries to monitor fetal exposures and pregnancy outcomes. Physicians report prenatal exposures and pregnancy outcomes, including birth defects, to these registries. We compared pooled data from four pregnancy registries with data from a population-based birth defects surveillance system, the Metropolitan Atlanta Congenital Defects Program (MACDP); specifically we compared the defect prevalence by organ system and severity, the number of defects per baby, and timeliness. We also compared the number of zidovudine exposures identified by a registry to the number identified by 29 states with HIV surveillance. The registries' overall defect prevalence (41/1471, 2.7%) was slightly lower than MACDP (6157/195642, 3.2%). The defect prevalence by organ system was similar, except for genitourinary defects which had a lower prevalence in the registries than in MACDP (RR = 0.22; 95% CI = 0.07,0.67). The prevalence of having an internal defect or severe defect reported was lower in the registries (RR = 0.75, 95% CI = 0.53,1.06, and RR = 0.82, 95% CI = 0. 57,1.19, respectively). The mean number of defects identified per affected infant was 2.82 in MACDP and 1.68 in the registries. Both systems received 69% of defect reports by 6 months after birth. In similar 6-month periods, U.S. HIV surveillance identified 300 prenatal zidovudine exposures, while the registry received 134 worldwide reports. If registries improve their ascertainment of defects and exposed pregnancies, they will increase their chance of detecting signs of possible teratogenicity. Teratology 60:356-364, 1999. Published 1999 Wiley-Liss, Inc.

Infantile hypertrophic pyloric stenosis after pertussis prophylaxis with erythromcyin: a case review and cohort study.

BACKGROUND: In February, 1999, a local US health department identified a cluster of pertussis cases among neonates born at a community hospital and recommended oral erythromycin for post-exposure prophylaxis for about 200 neonates born at that hospital between Feb 1 and Feb 24, 1999. We investigated a cluster of seven cases of infantile hypertrophic pyloric stenosis (IHPS) that occurred the following month among the neonates who had received erythromycin. METHODS: We obtained a masked, independent review of the IHPS ultrasonography diagnoses, calculated the monthly IHPS incidence, and compared index and historical (1998-99) IHPS cases with respect to several characteristics including erythromycin exposure. We used a retrospective cohort of infants born in January and February, 1999, to investigate further erythromycin exposure and development of IHPS. FINDINGS: An independent review confirmed the ultrasonographic diagnoses of all seven index IHPS cases. All index cases versus none of the historical IHPS cases had been given erythromycin for pertussis prophylaxis. The IHPS rate for infants born in the hospital in February, 1999, was 32.3 per 1000 liveborn infants, representing nearly a seven-fold increase over 1997-98 (relative risk 6.8 [95% CI 3.0-15.7]). Among infants born in January and February, 1999, erythromycin was associated with IHPS (absolute risk 4.5%, relative risk infinity [1.7-infinity]). INTERPRETATION: Neonates receiving oral erythromycin may have an increased risk of IHPS. The risks and benefits of erythromycin for neonatal pertussis prophylaxis should be re-evaluated, and caution should be used in defining risk groups for prophylaxis.

Laterality patterns in infants with external birth defects.

The lateral distribution of external birth defects has not been reported in a comprehensive way, and patterns in this distribution have not been examined. This study presents the lateral distribution of 6,390 unilateral defects from among 102 defect categories in data collected by the Metropolitan Atlanta Congenital Defects Program. Among all defects, 49% (95% CI 48-51%) were right-sided. Among males and females, 51% (95% CI 50-53%) and 47% (95% CI 46-49%) of the defects, respectively, were right-sided. Of the 102 defect types, 57 had an excess of defects on the right side of the body; 39 had an excess of defects on the left side; and 6 were equally distributed. The excess on the right side was statistically significant for inguinal hernia, incarcerated inguinal hernia, microtia, preauricular sinus, talipes calcaneovalgus, and lambdoidal craniosynostosis. For the left side, the excess was statistically significant for preauricular tags, cleft lip, fused lip and cleft gum, cleft lip with cleft palate, congenital hip dysplasia, unstable hip, absent forearm or hand, anomaly of the knee, and skin tags. The percentage of right-sided defects among case subjects with unilateral defects was correlated with the percentage of males among all case subjects (r = 0.24, P < 0.05). Among male case subjects with unilateral defects, the correlation coefficient was 0.31 (P < 0. 01), and among females with unilateral defects, it was 0.11 (P > 0. 10). Differences in the lateral distribution of specific birth defects may be due to subtle differences in morphogenesis on the left and right sides of the embryo brought about by establishment of left-right asymmetry prior to organogenesis. The fact that more defect categories were right-sided than left-sided may be related to the observation that mitochondrial maturation in rat embryos is delayed on the right side. The right side, therefore, may be more susceptible than the left to defects caused by prenatal hypoxia. The significant correlation between the percentage right-sided and percentage male may then also be related to the observation that male sex hormones lower the mitochondrial respiration rate in rats and increase rat sensitivity to chemical hypoxia. Investigators should consider reporting the laterality of specific defects in both laboratory and epidemiological studies of birth defects. Right- and left-sided defects should perhaps be considered separately in etiologic studies of birth defects. Teratology 60:265-271, 1999. Published 1999 Wiley-Liss, Inc.