The Kaiser Permanente Northern California research program on genes, environment, and health (RPGEH) pregnancy cohort: study design, methodology and baseline characteristics

Background

Exposures during the prenatal period may have lasting effects on maternal and child health outcomes. To better understand the effects of the in utero environment on children’s short- and long-term health, large representative pregnancy cohorts with comprehensive information on a broad range of environmental influences (including biological and behavioral) and the ability to link to prenatal, child and maternal health outcomes are needed. The Research Program on Genes, Environment and Health (RPGEH) pregnancy cohort at Kaiser Permanente Northern California (KPNC) was established to create a resource for conducting research to better understand factors influencing women’s and children’s health. Recruitment is integrated into routine clinical prenatal care at KPNC, an integrated health care delivery system. We detail the study design, data collection, and methodologies for establishing this cohort. We also describe the baseline characteristics and the cohort’s representativeness of the underlying pregnant population in KPNC.

Methods

While recruitment is ongoing, as of October 2014, the RPGEH pregnancy cohort included 16,977 pregnancies (53 % from racial and ethnic minorities). RPGEH pregnancy cohort participants consented to have blood samples obtained in the first trimester (mean gestational age 9.1 weeks ± 4.2 SD) and second trimester (mean gestational age 18.1 weeks ± 5.5 SD) to be stored for future use. Women were invited to complete a questionnaire on health history and lifestyle. Information on women’s clinical and health assessments before, during and after pregnancy and women and children’s health outcomes are available in the health system’s electronic health records, which also allows long-term follow-up.

Discussion

This large, racially- and ethnically-diverse cohort of pregnancies with prenatal biospecimens and clinical data is a valuable resource for future studies on in utero environmental exposures and maternal and child perinatal and long term health outcomes. The baseline characteristics of RPGEH Pregnancy Cohort demonstrate that it is highly representative of the underlying population living in the broader community in Northern California.

Electronic supplementary material

The online version of this article (doi:10.1186/s12884-016-1150-2) contains supplementary material, which is available to authorized users.

Severe hypotension in a patient receiving pemoline during general anesthesia

IMPLICATIONS

This case reports hypotension under general anesthesia in a patient taking pemoline. Vigilance for unexpected hypotension is important in patients who are treated with psychostimulants. If hypotension occurs, vasopressors that act directly on adrenergic receptors should be used.

Human contact with bait containing vaccine for control of rabies in wildlife

OBJECTIVE

To document the number of human contacts with bait containing liquid vaccinia-rabies glycoprotein (V-RG) vaccine, to evaluate factors that might affect human contact with bait-vaccine units, and to summarize adverse reactions in people after contact with vaccine.

DESIGN

Retrospective 4-year survey of directors of 6 oral rabies vaccination programs.

SAMPLE POPULATION

Human residents in areas of vaccination programs.

PROCEDURE

Data were collected from report forms and telephone conversations with directors of oral rabies vaccination programs in Florida, Massachusetts, New Jersey, Texas, and New York. Data collected included information regarding human contact with bait and vaccine, sex and age of person involved in contact, human population density, bait density, type of labeling used on bait, and other factors.

RESULTS

Human contact with bait was more likely in areas where bait had white labels (vs lettering in black ink) and in areas with high human population densities. Directors of all programs reported that human contact with bait-vaccine units was minimal. Adverse reactions in exposed people were not reported. On the basis of these findings, concerns about V-RG vaccine posing a substantial public health risk remain unfounded.

CLINICAL IMPLICATIONS

Directors of oral rabies vaccination programs should systematically collect information about exposures and potential factors affecting exposure of people to bait-vaccine units. People with substantial exposure to V-RG vaccine should be evaluated for immune status and any resulting symptoms should be documented and monitored.

Prevention of the spread of rabies to wildlife by oral vaccination of raccoons in Massachusetts

OBJECTIVE

To evaluate the use of bait containing rabies vaccine to create a barrier of rabies-vaccinated raccoons in Massachusetts and to determine the effectiveness of various bait distribution strategies in halting the spread of rabies.

DESIGN

Prospective study.

SAMPLE POPULATION

Free-ranging raccoons.

PROCEDURE

Baits were distributed twice yearly in a 207-km2 (80-mi2) area in the vicinity of the Cape Cod Canal. Bait density and distribution strategy varied among 3 treatment areas. Raccoons were caught in live traps after bait distribution and anesthetized; blood samples were obtained to measure serum antibody titers to rabies virus. Vaccination rates were determined by the percentage of captured raccoons with antibody titers to rabies virus > or = 1:5. In addition, raccoons with clinical signs of illness inside the vaccination zone and adjacent areas were euthanatized and submitted for rabies testing.

RESULTS

The percentage of vaccinated raccoons differed significantly among the following 3 areas with various bait densities: high-density area with uniform bait distribution (103 baits/km2 [267 baits/mi2]) = 37%; low-density area with additional targeted bait distribution (93 baits/km2 [240 baits/mi2]) = 67%; and, high-density area with additional targeted bait distribution (135 baits/km2 [350 baits/mi2]) = 77%. Nineteen animals with rabies (15 raccoons, 3 skunks, 1 cat) were reported in the area just outside of the vaccination zone, but only 1 raccoon with rabies was reported from inside the vaccination zone.

CLINICAL IMPLICATIONS

In this suburban study area, an approximate vaccination rate of 63% was sufficient to halt the spread of rabies in free-ranging raccoons. Compared with uniform bait distribution, targeting raccoon habitats increased vaccination rates.

Injuries treated at a sports injury clinic compared with a neighbouring accident and emergency department

Previous reports relating to sports injuries treated at hospital Accident and Emergency departments (A&E) or Sports Injury Clinics (SIC) indicate differences between the groups. This study compared directly the sports injuries treated during overlapping time periods at an A&E department (n = 2490) and a SIC (n = 340) set within the same geographical area. The two populations were found to differ significantly in age, sport, injury and injury site. Hospital patients tended to be younger, with an acute injury to the upper body or head which occurred during participation in sports where contact is likely. SIC patients tended to be older, with chronic or overuse injuries to the back or lower limb. It was found that there are significant differences between the sports injuries treated at the sports injury clinic and the hospital casualty department. It is concluded that demand is clearly shown for both types of treatment site when both are available in the same geographical area.

Anthropometric and training characteristics of female marathon runners as determinants of distance running performance

The purpose of this study was to determine how female marathon runners of varying standards differed in body composition and physique and in their training regimes, and secondly to develop predictors of distance running performance from the anthropometric and training variables. Female marathon runners (n = 36), all participants in a national 10 mile (16 km) road racing championship, were divided into three groups according to their best time for the 26.2 mile race. They were assessed for body composition and somatotype using anthropometric techniques and completed a questionnaire about their current training for the marathon. No difference was found between the groups of distance runners when measured for height, bone widths and circumferences. The three groups were found to have similar body weights of approximately 53 kg, a value which is much lower than the average for sedentary women, but which compares favourably with those from previous studies of female long distance runners. While all the runners had a lower per cent fat, as measured from skinfold thicknesses, than sedentary women, the elite runners were seen to have significantly lower values (P less than 0.05) than the other two groups. The difference in body fat was particularly reflected in the triceps skinfold value. There was also a tendency for the elite runners to be more ectomorphic and less endomorphic than the others. The better runners were seen, on the whole, to have been running longer, and to have more strenuous regimes, both in terms of intensity of training and distance run per week. Multiple regression and discriminant function analyses indicated that the number of training sessions per week and the number of years training were the best predictors of competitive performance at both 10 mile and marathon distances. They also indicated that a female long distance runner with a slim physique high in ectomorphy has the greatest potential for success.