Biomedical subjects

V J Carey

Publications and source records attributed to V J Carey.

At least 19 recordsLinked to original sources

PubMed2001

Analysis of longitudinally observed irregularly timed multivariate outcomes: regression with focus on cross-component correlation.

Components of repeatedly observed multivariate outcomes (for example, the two components of blood pressure measures (SBP(it), DBP(it)), obtained on subject i at arbitrarily spaced times t) are often analysed separately. We present a unified approach to regression analysis of such irregularly timed multivariate longitudinal data, with particular attention to assessment of the magnitude and durability of cross-component correlation. Maximum likelihood estimates are presented for component-specific regression parameters and autocorrelation and cross-correlation functions. The component-specific autocorrelation function has the 'damped exponential' form [see text], which generalizes the AR(1), MA(1) and random intercept models for univariate longitudinal outcomes. The cross-component correlation function (CCCF) has an analogous form, allowing damped-exponential decay of cross-component correlation as time between repeated measures elapses. Finite sample performance is assessed through simulation studies. The methods are illustrated through blood pressure modelling and construction of multivariate prediction regions.

Adult↗

PubMed2001

Exposure to cockroach allergen in the home is associated with incident doctor-diagnosed asthma and recurrent wheezing.

BACKGROUND: Indoor inhaled allergens have been repeatedly demonstrated to worsen asthma in sensitized individuals, but their role in incident asthma is more controversial. OBJECTIVE: We investigated the relationship between exposure to allergens (dust mite, cat, and cockroach) measured in the home and incident doctor-diagnosed asthma and recurrent wheezing in children born to parents with asthma, allergies, or both. METHODS: From an ongoing longitudinal family and birth cohort study, we identified 222 siblings (median age, 2.87 years) of the index children. Allergen levels in the home were measured from dust samples obtained at the beginning of the study. Incident doctor-diagnosed asthma and recurrent wheezing were determined from questionnaires administered at 14 months and 22 months after the initial questionnaire. RESULTS: Thirteen (5.9%) children were reported to have incident asthma, twenty (9.0%) children had recurrent asthmatic wheezing, and 18 (8.1%) had recurrent wheezing without asthma. Compared with children living in homes with Bla g 1 or 2 levels of less than 0.05 U/g, children exposed to Bla g 1 or 2 levels of 0.05 to less than 2 U/g had a relative risk for incident asthma of 8.27 (95% confidence interval, 1.04-66.04), whereas children exposed to Bla g 1 or 2 levels of 2 U/g or greater had a relative risk for incident asthma of 35.87 (95% confidence interval, 4.49-286.62). Cockroach allergen exposure was likewise a significant predictor for recurrent asthmatic wheezing. Neither dust mite nor cat allergen levels were significantly associated with either outcome. These findings remained after control for several covariates. CONCLUSION: Exposure to cockroach allergen early in life may contribute to the development of asthma in susceptible children.

Air Pollution, Indoor↗

PubMed2001

Bayesian inference on protective antibody levels using case-control data.

In the study of immune responses to infectious pathogens, the minimum protective antibody concentration (MPAC) is a quantity of great interest. We use case-control data to estimate the posterior distribution of the conditional risk of disease given a lower bound on antibody concentration in an at-risk subject. The concentration bound beyond which there is high credibility that infection risk is zero or nearly so is a candidate for the MPAC. A very simple Gibbs sampling procedure that permits inference on the risk of disease given antibody level is presented. In problems involving small numbers of patients, the procedure is shown to have favorable accuracy and robustness to choice/misspecification of priors. Frequentist evaluation indicates good coverage probabilities of credibility intervals for antibody-dependent risk, and rules for estimation of the MPAC are illustrated with epidemiological data.

Antibodies↗

PubMed2001

Polysaccharide biosynthesis locus required for virulence of Bacteroides fragilis.

Bacteroides fragilis, though only a minor component of the human intestinal commensal flora, is the anaerobe most frequently isolated from intra-abdominal abscesses. B. fragilis 9343 expresses at least three capsular polysaccharides-polysaccharide A (PS A), PS B, and PS C. Purified PS A and PS B have been tested in animal models and are both able to induce the formation of intra-abdominal abscesses. Mutants unable to synthesize PS B or PS C still facilitate abscess formation at levels comparable to those of wild-type 9343. To determine the contribution of PS A to abscess formation in the context of the intact organism, the PS A biosynthesis region was cloned, sequenced, and deleted from 9343 to produce a PS A-negative mutant. Animal experiments demonstrate that the abscess-inducing capability of 9343 is severely attenuated when the organism cannot synthesize PS A, despite continued synthesis of the other capsular polysaccharides. The PS A of 9343 contains an unusual free amino sugar that is essential for abscess formation by this polymer. PCR analysis of the PS A biosynthesis loci of 50 B. fragilis isolates indicates that regions flanking each side of this locus are conserved in all strains. The downstream conserved region includes two terminal PS A biosynthesis genes that homology-based analyses predict are involved in the synthesis and transfer of the free amino sugar of PS A. Conservation of these genes suggests that this sugar is present in the PS A of all serotypes and may explain the abscessogenic nature of B. fragilis.

Animals↗

PubMed2001

Tandem repeat deletion in the alpha C protein of group B streptococcus is recA independent.

Group B streptococci (GBS) contain a family of protective surface proteins characterized by variable numbers of repeating units within the proteins. The prototype alpha C protein of GBS from the type Ia/C strain A909 contains a series of nine identical 246-bp tandem repeat units. We have previously shown that deletions in the tandem repeat region of the alpha C protein affect both the immunogenicity and protective efficacy of the protein in animal models, and these deletions may serve as a virulence mechanism in GBS. The molecular mechanism of tandem repeat deletion is unknown. To determine whether RecA-mediated homologous recombination is involved in this process, we identified, cloned, and sequenced the recA gene homologue from GBS. A strain of GBS with recA deleted, A909DeltarecA, was constructed by insertional inactivation in the recA locus. A909DeltarecA demonstrated significant sensitivity to UV light, and the 50% lethal dose of the mutant strain in a mouse intraperitoneal model of sepsis was 20-fold higher than that of the parent strain. The spontaneous rate of tandem repeat deletion in the alpha C protein in vitro, as well as in our mouse model of immune infection, was studied using A909DeltarecA. We report that tandem repeat deletion in the alpha C protein does occur in the absence of a functional recA gene both in vitro and in vivo, indicating that tandem repeat deletion in GBS occurs by a recA-independent recombinatorial pathway.

Animals↗

PubMed2000

Use of capsular polysaccharide-tetanus toxoid conjugate vaccine for type II group B Streptococcus in healthy women.

An estimated 15% of invasive group B streptococcal (GBS) disease is caused by type II capsular polysaccharide (II CPS). In developing a pentavalent vaccine for the prevention of GBS infections, individual GBS CPSs have been coupled to tetanus toxoid (TT) to prepare vaccines with enhanced immunogenicity. Type II GBS (GBS II) vaccine was created by direct, covalent coupling of II CPS to TT by reductive amination. In 2 clinical trials, 75 healthy nonpregnant women 18-45 years old were randomized to receive II CPS-TT (II-TT) conjugate (dose range, 3.6-57 microg of CPS component) or uncoupled II CPS vaccine. Both vaccines were well tolerated. II CPS-specific IgG serum concentrations (as well as IgM and IgA) peaked 2 weeks after immunization, being significantly higher in recipients of conjugated vaccine than in recipients of uncoupled CPS. Immunological responses to conjugate were dose dependent and correlated with opsonophagocytosis in vitro. These results support inclusion of II-TT conjugate when preparing a multivalent GBS vaccine.

Adolescent↗

PubMed2000

Effect of molecular size on the ability of zwitterionic polysaccharides to stimulate cellular immunity.

The large-molecular-sized zwitterionic capsular polysaccharide of the anaerobe Bacteroides fragilis NCTC 9343, designated polysaccharide (PS) A, stimulates T cell proliferation in vitro and induces T cell-dependent protection against abscess formation in vivo. In the present study, we utilized a modification of a recently developed ozonolytic method for depolymerizing polysaccharides to examine the influence of the molecular size of PS A on cell-mediated immunity. Ozonolysis successfully depolymerized PS A into structurally intact fragments. PS A with average molecular sizes of 129.0 (native), 77.8, 46.9, and 17.1 kDa stimulated CD4+-cell proliferation in vitro to the same degree, whereas the 5.0-kDa fragment was much less stimulatory than the control 129.0-kDa PS A. Rats treated with 129.0-kDa, 46.9-kDa, and 17.1-kDa PS A molecules, but not those treated with the 5.0-kDa molecule, were protected against intraabdominal abscesses induced by challenge with viable B. fragilis. These results demonstrate that a zwitterionic polysaccharide as small as 22 repeating units (88 monosaccharides) elicits a T cell-dependent immune response. These findings clearly distinguish zwitterionic T cell-dependent polysaccharides from T cell-independent polysaccharides and give evidence of the existence of a novel mechanism for a polysaccharide-induced immune response.

Abdominal Abscess↗

PubMed1999

Results of physical inspection before races and race-related characteristics and their association with musculoskeletal injuries in Thoroughbreds during races.

OBJECTIVE: To estimate the relative risk of injury among horses deemed to be at increased risk of injury on the basis of prerace physical inspection findings and to examine the association of injury during races with race-related characteristics. DESIGN: Cohort study. ANIMALS: 2,187 Thoroughbred horses that started 3,227 races in Kentucky. PROCEDURE: All race starts for which a horse was deemed to be at increased risk of injury on the basis of prerace physical inspection findings and a random sample of race starts for which horses were not deemed at increased risk of injury were included in the study. Findings of prerace physical inspection, race-related characteristics, and outcome of the race (race results and whether the horse incurred an injury) were recorded for each race start. Race starts in which a horse incurred an injury during a race were compared with race starts in which injuries were not incurred to identify factors associated with injury during races. RESULTS: Abnormality of the suspensory ligament of the forelimbs detected during prerace physical inspection, racetrack, class of race (claiming race < or = $25,000 vs other classes), and distance of race (< 7 furlongs vs other distances) were significantly associated with increased risk of injury. CONCLUSIONS AND CLINICAL RELEVANCE: Prerace physical inspection findings, particularly abnormalities of the suspensory ligament, may be used to identify horses at increased risk of injury during races. Rate of injury differed among racetracks, and horses in certain types of races (lower-priced claiming races and races of shorter distance) may be at increased risk of injury during races.

Age Factors↗

PubMed1999

Race, socioeconomic factors, and area of residence are associated with asthma prevalence.

Asthma prevalence in the United States has been reported to be higher in minority groups such as Blacks and Hispanics. Because a disproportionate number of individuals from such minority groups are of low socioeconomic status (SES), it is unclear how much of the racial/ethnic differences in asthma prevalence is related to low SES. We investigated the effect of SES on the relationship between race/ethnicity and asthma prevalence in a cohort of families with a history of asthma or allergies from the Boston, Massachusetts area. From 499 families, a cohort of 998 parents and 307 children was identified. We used total yearly family income (<$50,000 vs. > or = $50, 000), highest level of education (< or = high school vs. > or = college), and residence in high-poverty areas vs. low-poverty areas as measures of SES. Yearly family income <$50,000, < or = high school education, and residence in high poverty areas were all associated with increased risks for asthma in both cohorts. In the parental cohort, Blacks and Hispanics (OR = 2.1, 95% CI = 1.5, 2.8; and OR = 2.2, 95% CI = 1.5, 3.2, respectively) were at greater risk for asthma than Whites. In the cohort of children, Black and Hispanic children (OR = 2.9, 95% CI = 1.0, 8.0; and OR = 5.3, 95% CI = 1.6, 17.5, respectively) were also at increased risk for asthma. When the three measures of SES were included in the multivariable models, the risks associated with Blacks and Hispanics decreased in both cohorts: OR = 1.4, 95% CI = 0.9, 2.0; and OR = 1.6, 95% CI = 1.0, 2. 6, respectively, for the parents; and OR = 0.8, 95% CI = 0.2, 3.0; and 2.5, 95% CI = 0.5, 11.7, respectively, for the children. We conclude that a large proportion of the racial/ethnic differences in asthma prevalence in our study is explained by factors related to income, area of residence, and level of education.

Adolescent↗

PubMed1999

Bronchodilator responsiveness and serum total IgE levels in families of probands with severe early-onset COPD.

Bronchodilator responsiveness has been associated with a subsequent accelerated decline in forced expiratory volume in one second (FEV1). Therefore, bronchodilator responsiveness and total serum immunoglobulin E(IgE) levels were assessed in 184 adult first-degree relatives of probands with severe early-onset chronic obstructive pulmonary disease (COPD) and a control group. Greater bronchodilator responsiveness was found among current smokers or exsmokers who were first-degree relatives of early-onset COPD probands than in currently or exsmoking controls, expressed as increase in FEV1 as a percentage of baseline (5.8+/-8.1 versus 2.9+/-5.1%, p<0.01), absolute increase in FEV1 from baseline (120+/-130 versus 60+/-110 mL, p<0.05), and increase in FEV1 as a percentage of the predicted value (3.6:4.1 versus 2.2+/-3.9%, p<0.05). However, elevated total serum IgE levels were not found in first-degree relatives of early-onset COPD probands compared with control subjects. The increased bronchodilator responsiveness among currently smoking/exsmoking first-degree relatives of early-onset COPD probands suggests that these individuals may have enhanced susceptibility to the detrimental effects of cigarette smoking.

Adult↗

PubMed1998

Abdominal adiposity and coronary heart disease in women.

CONTEXT: Obesity is a well-established risk factor for coronary heart disease (CHD), but whether regional fat distribution contributes independently to risk remains unclear. OBJECTIVE: To compare waist-hip ratio (WHR) and waist circumference in determining risk of CHD in women. DESIGN AND SETTING: Prospective cohort study among US female registered nurses participating in the Nurses' Health Study conducted between 1986, when the nurses completed a questionnaire, and follow-up in June 1994. PARTICIPANTS: A total of 44702 women aged 40 to 65 years who provided waist and hip circumferences and were free of prior CHD, stroke, or cancer in 1986. MAIN OUTCOME MEASURES: Incidence of CHD (nonfatal myocardial infarction or CHD death). RESULTS: During 8 years of follow-up 320 CHD events (251 myocardial infarctions and 69 CHD deaths) were documented. Higher WHR and greater waist circumference were independently associated with a significantly increased age-adjusted risk of CHD. After adjusting for body mass index (BMI) (defined as weight in kilograms divided by the square of height in meters) and other cardiac risk factors, women with a WHR of 0.88 or higher had a relative risk (RR) of 3.25 (95% confidence interval [CI], 1.78-5.95) for CHD compared with women with a WHR of less than 0.72. A waist circumference of 96.5 cm (38 in) or more was associated with an RR of 3.06 (95% CI, 1.54-6.10). The WHR and waist circumference were independently strongly associated with increased risk of CHD also among women with a BMI of 25 kg/m2 or less. After adjustment for reported hypertension, diabetes, and high cholesterol level, a WHR of 0.76 or higher or waist circumference of 76.2 cm (30 in) or more was associated with more than a 2-fold higher risk of CHD. CONCLUSIONS: The WHR and waist circumference are independently associated with risk of CHD in women.

Abdomen↗

PubMed1998

Molecular analysis of the role of the group A streptococcal cysteine protease, hyaluronic acid capsule, and M protein in a murine model of human invasive soft-tissue infection.

Human invasive soft-tissue infections caused by group A Streptococcus are associated with significant morbidity and mortality. To investigate the pathogenesis of these serious infections, we characterized the host response to bacterial challenge with an M-type 3 isolate recovered from a patient with necrotizing fasciitis, or with isogenic gene replacement mutants deficient in cysteine protease, hyaluronic acid capsule, or M protein in a murine model of human invasive soft-tissue infection. Animals challenged with the wild-type or cysteine protease-deficient strain developed spreading tissue necrosis at the site of inoculation, became bacteremic, and subsequently died. Histopathologic examination of the necrotic lesion revealed bacteria throughout inflamed subcutaneous tissue. Arterioles and venules in the subcutaneous layer were thrombosed and the overlying tissue was infarcted. In contrast, animals challenged with either an acapsular or M protein-deficient mutant developed a focal area of tissue swelling at the site of inoculation without necrosis or subsequent systemic disease. Histopathologic examination of the soft-tissue lesion demonstrated bacteria confined within a well-formed subcutaneous abscess. We conclude that the group A streptococcal hyaluronic acid capsule and M protein, but not the cysteine protease, are critical for the development of tissue necrosis, secondary bacteremia, and lethal infection in a murine model of human necrotizing fasciitis.

Abscess↗

PubMed1998

Pediatric AIDS prognosis using somatic growth velocity.

OBJECTIVE: To describe the natural history of somatic growth in HIV infection by constructing age-specific growth velocity norms and to assess specific prognostic information available using these norms. DESIGN: Observations on 1338 HIV-infected children aged 3 months to 15 years who participated in one of four US clinical trials of pediatric anti-HIV therapies were pooled; baseline growth velocity data were obtained using the first 6 months of observation for each child. METHODS: Distributions of physical growth velocities in HIV-infected children in the Pediatric AIDS Clinical Trials Group were computed. Statistical smoothing of growth histories was employed to derive velocity estimates, and quantile regression analysis of growth velocities was performed to allow comparisons of growth rates in age- and gender-heterogeneous cohorts in the context of HIV infection. The quantile regressions provide corrected z-scores for growth velocity that appropriately compare HIV-infected children with one another for the purpose of distinguishing more from less favorable prognoses. RESULTS: Consistent deficits in growth velocity amongst HIV-infected children were revealed when compared with the Fels Institute velocity standards. Approximately 33% of height (and 20% of weight) age- and sex-corrected velocity measurements obtained in the first 6 months of clinical trial participation lay beneath the corresponding third percentiles of the Fels reference distributions, which are commonly regarded as critical indicators of growth failure. Proportional hazards regression tests indicated that both weight and height velocity contributed significant information on the risk of death among children with AIDS after adjusting for antiretroviral therapy received, CD4 cell counts, and age at trial enrollment. Comparing subjects who differ in initial weight velocity by one age- and sex-corrected SD, the relative hazard of death was 0.63 (95% confidence interval, 0.55-0.72; P < or = 0.0001) in favor of the child with greater weight velocity, controlling for antiretroviral therapy received, age and CD4 cell count at baseline. The analogous hazard ratio for height velocity was 0.68 (95% confidence interval, 0.57-0.79; P < or = 0.0001). CONCLUSIONS: Suitably normalized growth velocities are informative and inexpensive criteria for pediatric AIDS prognosis; the growth velocity distributions presented will be useful for comparing growth effects of new therapeutic strategies to those of single and combination antiretrovirals employed for maintenance of pediatric HIV infection in the mid-1990s.

Acquired Immunodeficiency Syndrome↗

PubMed1998

Fish consumption and risk of sudden cardiac death.

CONTEXT: Dietary fish intake has been associated with a reduced risk of fatal cardiac end points, but not with nonfatal end points. Dietary fish intake may have a selective benefit on fatal arrhythmias and therefore sudden cardiac death. OBJECTIVE: To investigate prospectively the association between fish consumption and the risk of sudden cardiac death. DESIGN: Prospective cohort study. SETTING: The US Physicians' Health Study. PATIENTS: A total of 20 551 US male physicians 40 to 84 years of age and free of myocardial infarction, cerebrovascular disease, and cancer at baseline who completed an abbreviated, semiquantitative food frequency questionnaire on fish consumption and were then followed up to 11 years. MAIN OUTCOME MEASURE: Incidence of sudden cardiac death (death within 1 hour of symptom onset) as ascertained by hospital records and reports of next of kin. RESULTS: There were 133 sudden deaths over the course of the study. After controlling for age, randomized aspirin and beta carotene assignment, and coronary risk factors, dietary fish intake was associated with a reduced risk of sudden death, with an apparent threshold effect at a consumption level of 1 fish meal per week (P for trend=.03). For men who consumed fish at least once per week, the multivariate relative risk of sudden death was 0.48 (95% confidence interval, 0.24-0.96; P=.04) compared with men who consumed fish less than monthly. Estimated dietary n-3 fatty acid intake from seafood also was associated with a reduced risk of sudden death but without a significant trend across increasing categories of intake. Neither dietary fish consumption nor n-3 fatty acid intake was associated with a reduced risk of total myocardial infarction, nonsudden cardiac death, or total cardiovascular mortality. However, fish consumption was associated with a significantly reduced risk of total mortality. CONCLUSION: These prospective data suggest that consumption of fish at least once per week may reduce the risk of sudden cardiac death in men.

Adult↗

PubMed1998

Parental history and the risk for childhood asthma. Does mother confer more risk than father?

Although heredity plays a major role in asthma and in other allergic diseases, mechanisms underlying the inheritance of these disorders are poorly understood, as is the relative contribution of maternal and paternal conditions to risk of disease. We investigated doctor-diagnosed maternal and paternal asthma, eczema, and hay fever as cross-sectional predictors of childhood asthma and allergic disease in 306 children with a median age of 3.5 yr from families in which at least one parent had a history of either asthma or other allergic conditions. For both childhood asthma and eczema, the strongest parental predictors were the same conditions in the parents. For asthma in particular, maternal asthma was most strongly associated with asthma in the child over all ages in both univariate (OR = 3.2, 95% CI = 1.5 to 6.7) and multivariable (OR = 4.1, 95% CI = 1.7 to 10.1) models. Paternal asthma was weakly associated with childhood asthma in the univariate model (OR = 1.4, 95% CI = 0.6 to 3.2), but this association increased in magnitude in the multivariable model (OR = 2.7, 95% CI = 1.0 to 7.2). Among the children < 5 yr of age, the risk for childhood asthma associated with maternal asthma (OR = 5.0, 95% CI = 1.7 to 14.9) was greater than the risk associated with paternal asthma (OR = 1.6, 95% CI = 0. 5 to 5.9), whereas both maternal asthma and paternal asthma were associated with similar risks among children >= 5 yr of age (OR = 4. 6, 95% CI = 1.1 to 19.0 and OR = 4.1, 95% CI = 1.0 to 16.0, respectively). The odds of having a child with asthma were three times greater in families with one asthmatic parent and six times greater in families with two asthmatic parents than in families where only one parent had inhalant allergy without asthma; furthermore, inhalant allergy in one parent also conferred additional risk in the presence of asthma in the other parent. Further investigation is needed into the relative importance of genetic factors and in utero and postnatal exposures in determining the differential effects of maternal and paternal asthma on the development of childhood asthma.

Adult↗

PubMed1997

A prospective study of pregravid determinants of gestational diabetes mellitus.

CONTEXT: Gestational diabetes mellitus (GDM) affects 3% to 5% of pregnancies. Knowledge of risk factors for GDM is needed to identify possible preventive strategies. OBJECTIVE: To assess whether recognized determinants of noninsulin-dependent diabetes mellitus also may be markers for increased risk of GDM. DESIGN: Prospective cohort study. SETTING: The Nurses' Health Study II, which involves female US nurses aged 25 to 42 years at entry. PARTICIPANTS: The analyses included 14613 women without previous GDM or other known diabetes who reported a singleton pregnancy between 1990 and 1994. Of these women, 722 (4.9%) reported a new diagnosis of GDM. MAIN OUTCOME MEASURE: Self-report of GDM, validated by medical record review in a subset. RESULTS: In multivariate analyses including age, pregravid body mass index (BMI), and other GDM risk factors, the risk for GDM increased significantly with increasing maternal age (P for trend, <.01) and family history of diabetes mellitus (relative risk, 1.68; 95% confidence interval [CI], 1.39-2.04). Relative risks for GDM were 2.13 (95% CI, 1.65-2.74) for pregravid BMI of 25 to 29.9 kg/m2 and 2.90 (95% CI, 2.15-3.91) for BMI of 30 kg/m2 or more (vs BMI of <20 kg/m2). Risk for GDM increased with greater weight gain in early adulthood, and it also increased among nonwhite women. Pregravid current smokers had a relative risk for GDM of 1.43 (95% CI, 1.14-1.80), and pregravid vigorous exercise was associated with a nonsignificant reduction in GDM risk. CONCLUSIONS: Advanced maternal age, family history of diabetes mellitus, nonwhite ethnicity, higher BMI, weight gain in early adulthood, and cigarette smoking predict increased GDM risk. These observations may facilitate the identification of women at particular risk for GDM and suggest potential strategies for reducing this risk even before a woman becomes pregnant, such as avoiding substantial weight gain and smoking.

Adult↗

PubMed1997

Using hypertext and the Internet for structure and management of observational studies.

The evolution of computer and communications systems in the past decade brings new opportunities for increased efficiency and accuracy of observational studies. In ongoing, large scale research studies, the problem of bridging organizational and analytical methods of the past to modern methods of data structure and control can consume considerable effort. A model for information flow in an observational study is sketched, and the flow is found inherently complex. This complexity and corresponding managerial demands are compounded by database file proliferation and by evolution of system hardware and software. Interactive, network-based database mapping and documentation tools are described as currently implemented in an SAS-based system for the management and analysis of several large epidemiologic studies.

Computer Communication Networks↗

PubMed1997

Body fat distribution and risk of non-insulin-dependent diabetes mellitus in women. The Nurses' Health Study.

Obesity is an established risk factor for non-insulin-dependent diabetes mellitus (NIDDM). Anthropometric measures of overall and central obesity as predictors of NIDDM risk have not been as well studied, especially in women. Among 43,581 women enrolled in the Nurses' Health Study who in 1986 provided waist, hip, and weight information and who were initially free from diabetes and other major chronic diseases, NIDDM incidence was followed from 1986 to 1994. After adjustment for age, family history of diabetes, smoking, exercise, and several dietary factors, the relative risk of NIDDM for the 90th percentile of body mass index (BMI) (weight (kg)/height (m)2) (BMI = 29.9) versus the 10th percentile (BMI = 20.1) was 11.2 (95% confidence interval (CI) 7.9-15.9). Controlling for BMI and other potentially confounding factors, the relative risk for the 90th percentile of waist: hip ratio (WHR) (WHR = 0.86) versus the 10th percentile (WHR = 0.70) was 3.1 (95% CI 2.3-4.1), and the relative risk for the 90th percentile of waist circumference (36.2 inches or 92 cm) versus the 10th percentile (26.2 inches or 67 cm) was 5.1 (95% CI 2.9-8.9). BMI, WHR, and waist circumference are powerful independent predictors of NIDDM in US women. Measurement of BMI and waist circumference (with or without hip circumference) are potentially useful tools for clinicians in counseling patients regarding NIDDM risk and risk reduction.

Adult↗