Low-density lipoprotein particle size decreases during normal pregnancy in association with triglyceride increases.

OBJECTIVE: To characterize the changes in low-density lipoprotein (LDL) peak particle diameter (diameter of the predominant LDL subclass) in relation to changes in serum triglyceride concentration during successive stages of normal gestation and postpartum. METHODS: Nonfasting venous blood was obtained longitudinally during and after uncomplicated primiparous pregnancy from 10 nonsmoking women with no history of metabolic disorders. Plasma LDL diameter was determined by nondenaturing polyacrylamide gel electrophoresis. Serum concentrations of total cholesterol, triglyceride, apolipoprotein B, apolipoprotein A-I, and LDL-cholesterol were measured. Gestational changes were analyzed by one-way repeated-measures analysis of variance and the paired multiple comparison Student-Newman-Keuls test. Pearson coefficients were computed for correlation of serum lipids and LDL diameter. RESULTS: Low-density lipoprotein diameter decreased progressively with advancing gestation, evident by 16-20 weeks relative to 5-12 weeks. Seven of 10 cases were subclass pattern B (diameter less than 255 A) by term, indicating that small, dense particles predominated. The average diameter decrease from early to late gestation was 13 A. All subjects reverted to subclass pattern A (diameter 255 A or more) by 6-12 weeks postpartum, indicating prevalence of large, buoyant LDL. Low-density lipoprotein diameter correlated inversely with concentrations of serum triglyceride (r = -.61, P < .0001), apo B (r = -.66, P < .0001), cholesterol (r = -.53, P < .001), LDL cholesterol (r = -.45, P < .005), and apo A-I (r = -.39, P < .02). CONCLUSION: Gestational triglyceride increases are accompanied by progressive decreases in LDL diameter in a majority of cases. These changes undergo reversal postpartum and therefore are transient. Small, dense LDL particles have a number of properties capable of altering vascular function. However, the consequences of the gestational LDL size decrease for maternal and fetal metabolism remain unknown.

Human placental adenosine receptor expression is elevated in preeclampsia and hypoxia increases expression of the A2A receptor.

Placental hypoxia as a result of impaired trophoblast invasion is suggested to be involved in the pathophysiology of preeclampsia. Hypoxia is a potent stimulus for the release of adenosine, and the actions of adenosine are mediated through four adenosine receptors, A(1), A(2A), A(2B) and A(3). We investigated the presence, distribution and expression of adenosine receptor subtypes in the human placenta, the expression of the adenosine receptors in placentas from pregnancies complicated by preeclampsia, small for gestational age (SGA) infants and uncomplicated pregnancies, and the effect of hypoxia on placental adenosine receptor expression. Immunofluorescent microscopy localized A(1), A(2A), A(2B) and A(3) adenosine receptors to the syncytiotrophoblast, endothelial cells and myofibroblasts within the human placenta. Adenosine receptor protein and message expression levels were significantly higher in placentas from preeclamptic pregnancies with or without SGA infants, but not different in pregnancies with SGA infants alone. In vitro exposure of placental villous explants to hypoxia (2% oxygen) increased the expression of A(2A) adenosine receptor 50%. These data indicate that all four known adenosine receptors are expressed in the human placenta and adenosine receptor expression is significantly higher in pregnancies complicated by preeclampsia. These data are consistent with the hypothesis that differences in placental adenosine receptors may contribute to alterations in placental function in preeclampsia.

Relationships between maternal plasma leptin, placental leptin mRNA and protein in normal pregnancy, pre-eclampsia and intrauterine growth restriction without pre-eclampsia.

Leptin, an adipocyte hormone involved in energy homeostasis, is important in reproduction and pregnancy. Questions yet to be addressed include the source of higher leptin during pregnancy and its relationship to pregnancy outcome and fetal growth. The objective of this study was to investigate the relationship between placental leptin gene expression, placental leptin protein concentration and maternal plasma leptin concentration among control pregnant women, women with pre-eclampsia and women with growth-restricted infants. We also investigated the relationship between placental leptin expression and the placental expression of enzymes involved in cellular lipid balance: fatty acid translocase (CD36), carnitine palmitoyltransferase I (CPT-1B) and lipoprotein lipase (LPL). Placental leptin expression, placental protein and maternal plasma concentration were higher in pre-eclampsia than in controls but not in women with growth-restricted infants. Placental leptin expression and placental protein were higher in the preterm pre-eclamptic subjects, whereas maternal leptin was higher in the term pre-eclamptic subjects. The placental gene expression of CD36, CPT-1B and LPL were not different among the groups. This study suggests that despite similar failed placental bed vascular remodelling in pre-eclampsia and intrauterine growth restriction (IUGR), leptin gene expression is higher only in preterm pre-eclampsia.

Maternal serum soluble fms-like tyrosine kinase 1 concentrations are not increased in early pregnancy and decrease more slowly postpartum in women who develop preeclampsia.

OBJECTIVE: We measured maternal serum soluble fms-like tyrosine kinase 1 concentrations across pregnancy and immediately postpartum in women who developed preeclampsia and normal pregnant women. STUDY DESIGN: This was a nested case control study of 113 normal pregnant women and 55 women with preeclampsia. RESULTS: Serum soluble fms-like tyrosine kinase 1 concentrations increased similarly in early pregnancy in both groups. Mean serum soluble fms-like tyrosine kinase 1 concentrations were increased in women who developed preeclampsia, compared with normal pregnant women, and this increase was most pronounced in severe preeclampsia. However, many women with preeclampsia had soluble fms-like tyrosine kinase 1 concentrations similar to normal pregnant women. Lastly, soluble fms-like tyrosine kinase 1 decreased rapidly after delivery, but this decrease was significantly slower in women with severe preeclampsia. CONCLUSION: Increased soluble fms-like tyrosine kinase 1 is not an early-pregnancy event among women who later develop preeclampsia. Increased soluble fms-like tyrosine kinase 1 is more likely to be present in women with severe preeclampsia, but it is not present in all women with preeclampsia. Soluble fms-like tyrosine kinase 1 concentrations decrease more slowly after delivery in women with preeclampsia, consistent with a decreased rate of excretion or continued production.

Children hospitalized early and increased risk for future serious injury.

OBJECTIVE: To determine if infants hospitalized for any reason before 90 days of age are at increased risk for future serious injury. SETTING: Washington State. METHODS: A population based retrospective cohort study, using data from Washington State birth and death certificates linked to a statewide hospital discharge database for the years 1989 through 1997. Participants included healthy full term infants born in Washington State between 1989 and 1995. A total of 29,466 infants hospitalized <90 days of age (early hospitalization) were compared to 29,750 randomly selected infants not hospitalized early. The primary outcome was an injury resulting in hospitalization or death between 3-24 months. RESULTS: Among infants hospitalized early, 76/10,000 had a subsequent serious injury before age 2, compared with 47/ 10,000 infants without an early hospitalization (relative risk (RR) 1.6; 95% confidence interval (CI) 1.3 to 2.0). In a multivariate model including maternal age and parity, the adjusted RR for serious injury associated with early hospitalization was 1.5 (95% CI 1.2 to 1.8). Infants hospitalized early were three times as likely to be hospitalized between 3-24 months of age for intentional injury compared with infants not hospitalized early (RR 3.3; 95% CI 1.1 to 10.1). CONCLUSIONS: Infants hospitalized in the first three months of life for any reason were 50% more likely to have a subsequent serious injury compared with infants not hospitalized early and were also at increased risk of intentional injury. This identifiable group of infants might be suitable for targeted childhood injury prevention programs including those involving prenatal and postnatal visits.

Obesity among Mescalero preschool children. Association with maternal obesity and birth weight.

The prevalence of obesity among native American children ranks with the highest in the United States. However, little is known about associated risk factors for obesity among these children. We conducted a medical record review of 261 preschool children enrolled in the Mescalero Apache tribe to determine the prevalence of obesity and associated risk factors. The prevalence of obesity (weight for height greater than 95th percentile) in this population was 19.5%. The prevalence of obesity (body mass index greater than 95th percentile) in their mothers was 23%. Children with obese mothers were more than twice as likely to be obese than children of nonobese mothers. Children with a high birth weight were three times as likely to be obese as children of low or normal birth weight. The high prevalence of obesity may be due to both life-style and dietary patterns on the reservation. Family-based interventions are needed to prevent obesity and its long-term consequences in this population.

The impact of the standards for pediatric immunization practices on vaccination coverage levels.

OBJECTIVE: To assess the impact on clinic-specific vaccination coverage of implementing the Standards for Pediatric Immunization Practices. DESIGN: A nonrandomized intervention trial conducted for 1 year. SETTING: Two public health clinics in Albuquerque, NM: 1 intervention site and 1 control site, each serving 1 of 4 city quadrants. PARTICIPANTS: All children enrolled in the 2 city public health clinics. INTERVENTIONS: Implementation of the Standards for Pediatric Immunization Practices. OUTCOME MEASURES: Assessment of up-to-date vaccination coverage levels prior to and at the conclusion of the project. The impact on the proportion of children who dropped out of vaccination services after receiving 1 dose by 3 months of age. RESULTS: At the intervention site, up-to-date coverage at 12 months of age rose from 57.5% to 80.4%, while levels at the control site decreased from 42.1% to 41.9%. Before the intervention, 24% of children at the intervention site who received the first dose of diphtheria and tetanus toxoids and pertussis vaccine (DTP 1) by 3 months of age failed to receive the third dose of DTP (DTP 3) by 12 months of age vs 5% after the intervention. At the control site, the proportion of children who received DTP 1 by 3 months of age, but not DTP 3 by 12 months of age, increased from 39% to 51%. CONCLUSION: Implementation of the Standards for Pediatric Immunization Practices in a public health clinic was associated with important increases in vaccination coverage levels and a reduction in the proportion of children who dropped out of vaccination services.

Trends in anthropometric measurements among Mescalero Apache Indian preschool children. 1968 through 1988.

OBJECTIVE: To determine if there were trends in underweight, short stature, and obesity among 1- through 5-year-old Mescalero (NM) Apache Indian children from 1968 through 1988. DESIGN: Cross-sectional review of hospital clinic charts for five cohorts. SETTING: General pediatric outpatient clinic at the Mescalero Indian Health Service Hospital. PARTICIPANTS: Sixty-nine patients aged 1 through 5 years in 1968, 1973, 1978, 1983, or 1988 for whom weight and height were recorded during a well-child visit that occurred in the respective year. SELECTION PROCEDURES: Approximately half the charts were screened for eligibility through systematic sampling for all years except 1988; for 1988 all available charts were screened for eligibility for the study. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: We found trends of decreasing prevalence of both underweight (defined as weight-for-height below the fifth percentile) and short stature (defined as height-for-age below the fifth percentile) based on the Centers for Disease Control/World Health Organization growth reference. We found no secular trends in obesity (weight-for-height above the 95th percentile), although the prevalences throughout the 21-year period were as much as two to four times higher than expected when compared with the Centers for Disease Control/World Health Organization reference. There has been an upward shift in both weight-for-height and height-for-age distributions since 1968, indicating that Mescalero children today are, on average, heavier and taller. CONCLUSIONS: Underweight and short stature decreased among Mescalero preschool children from 1968 through 1988, suggesting nutritional improvements. However, given the current high prevalence of obesity, it is recommended that surveillance of nutritional status be continued and appropriate interventions be developed to treat and prevent obesity in this population.

Pedestrian and hypothermia deaths among Native Americans in New Mexico. Between bar and home.

OBJECTIVE: To determine the nature of excess injury mortality among Native Americans in New Mexico. DESIGN: Retrospective review of death certificates for deaths from unintentional injuries. SETTING: The state of New Mexico. SUBJECTS: New Mexico residents who died of unintentional injuries between January 1, 1980, and December 31, 1989. MAIN OUTCOME MEASURE: Cause-specific mortality rates. RESULTS: Over half of the excess mortality from all unintentional injuries among Native Americans resulted from hypothermia and from pedestrian-motor vehicle crashes. New Mexico Native Americans were nearly eight times more likely to die in pedestrian--motor vehicle crashes and were 30 times more likely to die of hypothermia compared with other New Mexico residents. At death, 90% of those Native Americans tested were highly intoxicated (median blood alcohol concentrations of 0.24 and 0.18 g/dL [corrected] for pedestrian and hypothermia deaths, respectively). Despite the fact that most Native Americans in New Mexico live on reservations, most deaths occurred at off-reservation sites in border towns and on roads leading back to the reservation. CONCLUSIONS: The possession and sale of alcohol is illegal on many Native American reservations. This policy forces Native Americans who want to drink to travel long distances to obtain alcohol. These data suggest that this policy is also the likely explanation for the markedly increased risk of death from hypothermia and pedestrian-motor vehicle crashes in this population.

Firearms in New Mexico.

To determine the prevalence of firearm ownership and storage practices in New Mexico, we did a random-digit-dialing survey of New Mexico residents in October 1991. Of 200 households surveyed, 79 (40%) had 1 or more firearms in the home. Rural households were more likely than urban households to have firearms (44% versus 30%), and households with annual incomes of greater than $25,000 were more likely to have a firearm than households with incomes of $25,000 or less (41% versus 33%). Household firearm ownership did not vary with the presence of young (< 15 years old) children (38% with children versus 41% without). Handguns were generally owned for self-protection, and rifles were owned for hunting. Of households with firearms, 24% stored them unsafely (unlocked and loaded or unloaded but with ammunition nearby), including 21% of households with young children. Of the households with handguns only, 40% stored these firearms unsafely compared with 13% of those with rifles only. The prevalence of gun ownership in New Mexico is similar to that reported in national surveys; handguns are stored less safely than rifles; and the presence of young children in the home does not appear to improve firearm storage safety.

Cryptosporidiosis and surface water.

In the period July through October, 1986, 78 laboratory-confirmed cases of cryptosporidiosis were identified in New Mexico. To determine possible risk factors for development of this disease, we conducted a case-control study; 24 case-patients and 46 neighborhood controls were interviewed. Seventeen (71 per cent) of the 24 case-patients were females, seven (29%) were males; their ages ranged from 4 months to 44 years, median 3 years. There was a strong association between drinking surface water and illness: five of the 24 case-patients, but none of the 46 controls drank untreated surface water. Among children, illness was also associated with attending a day care center where other children were ill (odds ratio = 13.1).

Comparison of HIV-antibody prevalence in patients consenting to and declining HIV-antibody testing in an STD clinic.

All patients attending a sexually transmitted disease (STD) clinic were offered voluntary, anonymous human immunodeficiency virus (HIV)-antibody testing and counseling as part of routine clinical evaluation. During a three-month evaluation period, 82% of patients accepted HIV testing. Testing was accepted equally by men and women and by heterosexual and homosexual men. Black men were more likely to refuse testing than men from other ethnic groups. Eight (0.7%) of 1146 STD clinic patients tested were infected with HIV. A blinded study of 237 patients who refused testing identified nine (3.8%) additional HIV-infected patients. Men who refused testing were 5.3 times more likely to be infected than men who accepted testing. Male homosexuals and black and Hispanic men who refused testing were 7.3 and 8.8 times, respectively, more likely to be infected with HIV than were their counterparts who accepted testing. Human immunodeficiency virus testing and counseling should be routinely offered to STD clinic patients. Male STD clinic patients, especially homosexual or minority men, who refuse voluntary HIV testing should be counseled regarding reducing their risk for HIV transmission.

KIE: Results of voluntary, anonymous human immunodeficiency virus (HIV) antibody testing and counseling offered to all patients attending a sexually transmitted disease (STD) clinic showed that men who refused testing were 5.3 times more likely to be infected than men who accepted testing, and that male homosexuals and black and Hispanic men who refused testing were even more likely to be infected than their counterparts who accepted testing. The prevalence of HIV infection in persons refusing HIV testing was determined in a retrospective, blinded study using stored serum specimens originally drawn for syphilis testing. It is recommended that HIV testing and counseling should be routinely offered to STD clinic patients; male STD clinic patients who refuse voluntary HIV testing should be counseled about reducing their risk for HIV transmission.

Effects of the 65-mph speed limit on rural interstate fatalities in New Mexico.

As a result of federal legislation passed in April 1987, New Mexico was the first state to resume a 65-mph speed limit on rural Interstate highways. We compared the rates of fatal crashes before and after the speed limit change. The rate of fatal crashes in the 1 year after the speed limit was increased was 2.9 per 100 million vehicle-miles traveled, compared with a predicted rate of 1.5 per 100 million vehicle-miles based on the trend of the 5 previous years. When fatal crashes that occurred after the speed limit change were compared with fatal crashes in the 5 previous years, there was no difference in the mean age and sex of the at-fault drivers, mean age and sex of the victims, seat belt use by the victims, or alcohol involvement of the crashes. The increase in fatal crashes can be attributed to an increase in fatal single-vehicle crashes. Vehicles on rural Interstates are traveling at greater rates of speed and a larger proportion of vehicles are exceeding the 65-mph speed limit. The benefits associated with the 65-mph speed limit should be weighed against the increased loss of lives.

Clinical features that differentiate hantavirus pulmonary syndrome from three other acute respiratory illnesses.

To elucidate the early clinical characteristics of hantavirus pulmonary syndrome (HPS), we compared the clinical features of 24 cases of HPS with those of cases of bacteremic pneumococcal pneumonia (n = 30), influenza (n = 33), or unexplained adult respiratory distress syndrome (ARDS, n = 21). On admission, patients with HPS were less likely than outpatients with influenza to have reported sore throat (OR = 0.02, P < .01) and cough (OR = 0.1, P = .01) and were less likely than patients with pneumococcal pneumonia to have lobar infiltrates detected by chest roentgenography (OR = 0, P < .01). Multivariate discriminant analysis revealed that three clinical characteristics at admission (dizziness, nausea or vomiting, and absence of cough) and three initial laboratory abnormalities (low platelet count, low serum bicarbonate level, and elevated hematocrit level) served to identify all patients with HPS and to exclude HPS in at least 80% of patients with unexplained ARDS. These findings warrant further study and should facilitate the early recognition of patients with HPS, who may benefit from early critical-care intervention.