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PubMed2001

Risk factors for low birthweight in north-east Brazil: the role of caesarean section.

Caesarean section (CS) delivery is associated with low birthweight (LBW) in south-east Brazil. A hospital-based study was conducted on singleton infants from mothers residing in São Luís, to assess if an association between CS and LBW was found in the northern part of the country, where the CS rate is lower than in the south-east. A standardised questionnaire was administered to a sample of 2541 mothers in 10 hospitals, representing 94% of all deliveries, from March 1997 to February 1998. In a logistic model, type of delivery was the independent variable, the other variables were treated as confounders, and interaction terms were added between type of delivery and all other factors. LBW was associated with low maternal height, maternal smoking, primiparity, previous LBW, public insurance, preterm birth and CS. The CS rate was 33.7%. The risk of CS was higher for primiparous and married mothers, those with high level of schooling and attended by the same physician during prenatal and delivery care, deliveries held in private hospitals, daylight hours or evenings, and for those mothers who had adequate prenatal care. Because it appears unlikely that only medical reasons are operative, it is a possibility that CS could cause LBW, reflecting abusive indications for elective CS.

Adult↗

PubMed2005

Improvement of a questionnaire measuring activity limitations in rising and sitting down in patients with lower-extremity disorders living at home.

OBJECTIVE: To improve a self-administered questionnaire that includes 42 dichotomous items and measures activity limitations in rising and sitting down (R&S) in patients with lower-extremity disorders who live at home. DESIGN: Cross-sectional study. SETTING: Outpatient clinics of secondary and tertiary care centers. PARTICIPANTS: Patients (N=759; 47% men; mean age +/- standard deviation, 60.7+/-15.2y) living at home, with lower-extremity disorders resulting from stroke, poliomyelitis, osteoarthritis, amputation, and complex regional pain syndrome type I. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: (1) Unidimensionality, indicating that items assess only a single construct; (2) fit with the one-parameter logistic model (OPLM), yielding information about patient and item location parameters; (3) intratest reliability, indicating consistency of patients' item scores; and (4) content validity, indicating completeness with which the items cover the important aspects of the construct that they are attempting to represent. RESULTS: Thirty-nine of 42 items: (1) loaded on 1 component (variance explained, 59%; item component loadings, >or=.51), (2) showed good fit with the OPLM (P=.15), (3) had a good intratest reliability (Cronbach alpha=.96), and (4) had a good content validity (all important aspects represented). CONCLUSIONS: A unidimensional scale that fits with the OPLM has been developed for measuring activity limitations in R&S in patients with lower-extremity disorders who live at home.

Activities of Daily Living↗

PubMed1997

Value of preoperative CA 125 level in the management of uterine cancer and prediction of clinical outcome.

OBJECTIVE: To enhance cost-effective management of uterine cancer by predicting the likelihood of extrauterine disease and survival on the basis of preoperative parameters. METHODS: A retrospective review of preoperative CA 125 levels from 210 women with endometrial carcinoma was performed. The relationship of preoperative CA 125 levels to various preoperative and postoperative histopathologic factors was investigated. RESULTS: Elevated CA 125 (greater than 35 U/mL) correlated (P < .05) with higher stage, higher grade, increased depth of myometrial invasion, positive cytology, pelvic or para-aortic lymph node metastases, and reduced actuarial survival (P < .001). Multivariate analysis of preoperative factors showed that an elevated CA 125 level was the most important predictor for poor survival (P < .001). Moreover, a preoperative CA 125 level greater than 65 U/mL was the most significant predictor of extrauterine disease and carried a 6.5-fold higher risk (95% confidence interval 2.5, 17.1). A logistic model to predict extrauterine disease was developed. The model has a sensitivity of 62%, specificity of 91%, positive predictive value of 69%, and negative predictive value of 88%. CONCLUSION: A CA 125 level should be included as part of the preoperative workup for all patients with uterine cancer. Patients with a preoperative CA 125 level less than or equal to 20 U/mL should be considered as candidates for vaginal hysterectomy unless unfavorable histology or a high-grade (grade II or III) tumor is present. In our series, this approach would have eliminated 24% of the abdominal staging procedures, with a risk of less than 3% for extrauterine disease, while lowering treatment-related morbidity and cutting costs in the treatment of this common female cancer.

Adult↗

PubMedDate not supplied

A study of clients returning for counseling after HIV testing: implications for improving rates of return.

Pretest and posttest counseling have become standard components of prevention-oriented human immunodeficiency virus (HIV) antibody testing programs. However, not all persons who receive pretest counseling and testing return for posttest counseling. Records of 557,967 clients from January through December 1990, representing more than 40 percent of all publicly funded HIV counseling and testing, were analyzed to determine variables independently associated with returning for HIV posttest counseling. On average, 63 percent of clients returned for posttest counseling. The rate varied by self-reported risk behavior, sex, race or ethnicity, age, site of counseling and testing, reason for visit, and HIV serostatus. In multivariate logistic models, persons who were young, African American, and pretest counseled in sexually transmitted disease (STD) clinics or family planning clinics were least likely to return for posttest counseling. Those clients who consider themselves to be at risk for HIV infection may be more likely to act on that perception and to follow through with posttest counseling than those who do not perceive risk. Counselors should make special efforts during pretest counseling to encourage adolescents, members of racial or ethnic minorities, and persons seen in STD and family planning clinics to return for posttest counseling by helping them understand and accept their own personal risk of HIV infection. Counselors need to establish, with the client's participation, a specific plan for receiving test results and posttest counseling.

Adolescent↗

PubMed1996

Risk factors associated with the severity of systemic insect sting reactions.

To evaluate risk factors associated with the severity of systemic insect sting reaction and to determine the type of insect responsible for systemic anaphylaxis, we conducted a cross-sectional study of 498 patients undergoing venom immunotherapy for insect sting reaction in 13 allergy clinics in Israel. Data were collected by questionnaire and review of patient records. Eighty percent of the patients were treated with honeybee venom, which was used as a single therapy in 60% of the group. In a multivariate logistic model the major factors identified as significantly influencing the probability of a more severe systemic reaction were short time of onset of reaction after stinging (<30 min), high number of prior stings (> or = 4), and age (> or = 18 years). A total of 79.3% of the patients had been stung outdoors, and 50% had lived all their lives in rural areas as compared to 10% in the general Israeli population. This study reports clinically valuable risk factors for the severity of systemic sting reaction. A practical finding was that the honeybee is the insect mostly responsible for sting reactions in Israel, but the type of insect is not a significant predictor of the severity of the reaction.

Adolescent↗

PubMed1994

Characteristics of work and life predicting coronary heart disease. Finnish research project on aging workers.

This study focussed on features of work and lifestyle predicting coronary heart disease. In 1981 the 5353 subjects were active Finnish municipal employees, aged 44-58 years. They answered a postal inquiry in 1981 and 1985. The cumulative incidence of coronary heart disease was 3.5% (188). The predictors were selected by discriminant analytic methods and logistic models. The risk for women was explained best by physically too heavy work (RR 2.5, 95% CI 1.3-4.8), and residence in north-eastern Finland (RR 2.0, 95% CI 1.1-3.4). The risk for men was explained best by three factors: smoking (RR 2.3, 95% CI 1.4-3.9), frequent walking or moving about at work (RR 1.7, 95% CI 1.2-2.4), and a household with two or more unemployed members over 15 years of age (RR 1.7, 95% CI 1.2-2.5). These men often had a secondary job or had done much housework. The risk of coronary heart disease was associated with physically heavy work before the age of 20, first employment at a young age, and building their own house around the beginning of the follow-up.

Adult↗

PubMed1997

Consistency of Doppler parameters in predicting arteriographically confirmed carotid stenosis. Asymptomatic Carotid Atherosclerosis Study Investigators.

BACKGROUND AND PURPOSE: While internal carotid peak systolic velocity (IPSV) is reportedly the best Doppler parameter for predicting lower grades of carotid artery stenosis, the internal carotid end-diastolic velocity (IEDV) or the ratio of IPSV to common carotid end-diastolic velocity (CEDV) is helpful in increasing prediction of higher grade stenoses. It is important to examine the consistency of these findings across machine and technician. METHODS: Using data from 10 devices from the Asymptomatic Carotid Atherosclerosis Study, we examined the predictive ability of seven Doppler parameters: IPSV, IEDV, CEDV, common carotid peak systolic velocity (CPSV), and the ratios of IPSV/ CEDV, IEDV/CEDV, and IEDV/CEDV. To assess the agreement between Doppler and arteriography in classifying percent stenosis above or below a given criterion, sensitivity, specificity, area under the receiver operating curve, and kappa statistics were obtained from logistic models. The single best Doppler parameter for each of two grades of stenosis (60% and 80%) was determined, and its predictive ability was compared with that of IPSV. The usefulness of IEDV or IPSV/CEDV in addition to IPSV to determine higher grade stenosis was examined. RESULTS: IPSV was the best predictor in 9 of 10 devices at 60% and in 4 devices at 80% stenosis. When another parameter was better than IPSV, the improvement was minimal. Including IEDV or IPSV/CEDV in addition to IPSV did not notably improve predictive ability. CONCLUSIONS: IPSV is the single best Doppler parameter for distinguishing severe (> 80%) from less severe carotid stenosis. Information from other Doppler parameters in addition to IPSV is unlikely to be helpful.

Blood Flow Velocity↗

PubMed1997

Mortality, severe respiratory distress syndrome, and chronic lung disease of the newborn are reduced more after prophylactic than after therapeutic administration of the surfactant Curosurf.

OBJECTIVE: To test the hypothesis that prophylactic treatment with the surfactant Curosurf (Chiesi Farmaceutici SPA, Parma, Italy) improves survival and respiratory problems more than rescue treatment. DESIGN: Meta-analysis of three prophylaxis versus rescue treatment trials, conducted in four countries. METHODS: A meta-analysis was performed with the original, individual data of mortality, severe respiratory distress syndrome, and chronic lung disease of 671 newborns as outcomes. The random-effects logistic model (accounting for the trial-within-country structure) was applied and adjusted for imbalances in covariates. RESULTS: The probability of each outcome differed between the countries, but the actual treatment effect itself did not. The adjusted odds ratios (ORs) and confidence intervals (CIs) for prophylaxis versus rescue were as follows: mortality: OR, .47; 95% CI, .30 to .73; severe RDS: OR, .50; 95% CI, .33 to .74; and chronic lung disease of the newborn in the survivors at day 28 after birth: OR, .54; 95% CI, .34 to .86. Gender, birth weight, gestational age, and prenatal administration of glucocorticosteroids were significant confounding covariates. CONCLUSION: The analysis shows that for the porcine surfactant Curosurf, prophylactic administration of surfactant has significant advantages over rescue therapy.

Biological Products↗

PubMed1990

Statistical analysis of the clinical trial of a therapy for Alzheimer's disease. Univariate tests and logistic regression.

A placebo controlled, randomized, double blind, multicentric clinical trial was carried out in Italy to test the effectiveness of a drug in the therapy of Alzheimer's disease. Informed consensus was gained for the inclusion of 130 patients, whose mental performance was assessed before allocation and after 3, 6, 12 months of continuing assumption of treatment. 14 different outcome variables were used. The main analysis was performed on measures adjusted for baseline, using both univariate and multivariate techniques for each of the three assessing times. The former is mainly descriptive in its scope and allows an analytical view of the results; the latter protects from a too high type I error probability, without implying the loss of power produced by the Bonferroni correction. The techniques are respectively Mann-Whitney test, and analysis of deviance of logistic models, which was suggested by Cupples et al. (1984). In the latter we used the allocation of the patients as response variable, and compared the predictor containing all outcome measures with that having just a constant term. It is shown that a significant difference of fit implies that treatment significantly affects outcome. For the 3 and 6 month follow-up assessment, univariate tests do not show clearcut trends (only 1 outcome measure is significantly better for the drug, none is for the placebo). After 12 months, a trend shows: 13 out of 14 variables are in favour of the drug and 4 of them are significant. Of the three multivariate test carried out, that relative to the 12-month follow-up is significant at the 0.05 level, which is consistent with the univariate results.(ABSTRACT TRUNCATED AT 250 WORDS)

Alzheimer Disease↗

PubMed1995

Clustering of risk habits in young adults. The Cardiovascular Risk in Young Finns Study.

The authors studied the occurrence of common lifestyle risk factors, namely, nonprudent diet, smoking, physical inactivity, and frequent inebriation by alcohol in a cohort of young adults aged 18, 21, and 24 years (n = 484) as part of the Cardiovascular Risk in Young Finns Study in 1986. Risk habits showed significant clustering; the number of subjects was greater than expected in groups with zero and three of four risk habits and less than expected in the group with only one or two risk habits. Stepwise logistic regression analysis was used to find independent determinants for this clustering from a set of socioeconomic, demographic, and behavioral (type A components) determinants. The logistic model suggested several independent risk factors for risk habit clustering. These included male sex, aggressiveness, and past unemployment. Paying a lot of attention to health habits, higher education (being a student), good self-perceived health, and a high sense of responsibility seemed to be protective factors against risk habit clustering. The accumulation of risk habits was also associated with an atherogenic lipid and blood pressure profile (clustering of high density lipoprotein cholesterol/total cholesterol ratio, triglycerides, and diastolic blood pressure in their extreme tertiles). These findings show that common risk habits cluster among young adults. Knowledge about the determinants of this clustering will aid in the planning of future preventive strategies against cardiovascular diseases in young people.

Adolescent↗

PubMed1997

Racial and ethnic differences in determinants of intrauterine growth retardation and other compromised birth outcomes.

OBJECTIVES: This study examined the extent of variation by race/ethnicity in the prevalence of adverse birth outcomes, whether differentials persisted after other risk factors were controlled for, and whether the direction and magnitude of relationships differed by type of outcome. METHODS: A revised system of measurement was used to estimate multinomial logistic models in a large, nationally representative US data set. RESULTS: Considerable racial/ethnic variation was found across birth outcome categories; differences persisted in the adjusted parameter estimates; and the effects of other risk factors on birth outcomes were similar as to direction, but varied somewhat in magnitude. The odds of compromised birth outcomes were much higher among African Americans than among Mexican Americans and non-Hispanic Whites. CONCLUSIONS: In addition to persistent racial inequality, we found strong adverse effects of both inadequate and "adequate-plus" prenatal care and smoking. Risk of intrauterine growth retardation was higher in the absence of medical insurance, and risk of all adverse birth outcomes was lower among mothers participating in the Special Supplemental Food Program for Women, Infants, and Children.

Adolescent↗

PubMed1994

[Clinical factors relating to the presence of serum anti-GM1 and GD1b antibodies in demyelinating neuropathy--study using a multivariate analysis].

We studied clinical factors relating to the presence of serum anti-GM1 and GD1b antibodies in patients with demyelinating neuropathy using a multivariate analysis. Sera were obtained from 46 patients with chronic inflammatory demyelinating polyneuropathy (CIDP) and 33 with Guillain-Barré syndrome (GBS) and kept frozen at -20 degrees C until use. Anti-GM1 and GD1b IgM and IgG antibodies were measured by ELISA at serum dilution of 1:100 and considered to be positive when those values were more than the cut off values determined by means and standard deviations in 35 normal controls. Age, sex, duration, prodromal disease, neurological findings, concentration of CSF protein, nerve conduction, treatment, and outcome were investigated in all patients retrospectively. Multivariate logistic models using all those characteristics were used to clarify the clinical factors relating to the presence of anti-GM1 and GD1b antibodies. In CIDP, anti-GM1 antibodies associated with or without anti-GD1b antibodies were frequently seen in patients with motor dominant neuropathy than those with sensory dominant neuropathy (P = 0.007, odds ratio = 11.6). There was significant difference in anti-GM1 IgM antibodies (P = 0.003, odds ratio = 22.2), but no difference in IgG antibodies. Anti-GM1 antibodies were observed 5 (IgM, 5; IgG, 2) of 7 patients with pure motor neuropathy, 9 (IgM, 8; IgG, 4) of 17 with motor dominant neuropathy, 5 (IgM, 2; IgG, 3) of 16 with sensori-motor neuropathy, and none of 6 with sensory dominant neuropathy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed2004

Characteristics of sexual partners and STD infection among American adolescents.

Adolescents are a high risk group for HIV infection and the characteristics of their partners may affect their susceptibility to infection. The goal of this study was to examine the effects of partner characteristics on sexually transmitted disease (STD) infection in a national sample of adolescents. Data from 8,024 sexually active adolescents who participated in the National Longitudinal Study of Adolescent Health (Add Health) in the United States were included in this study. Logistic models were used to examine the association of partner characteristics including age, neighbourhood, ethnicity, and school attendance on the self-report history of STD infection. The partner characteristics of age and school attendance were associated with the reporting of STD infection. The odds ratio for STD infection was 1.46 (95% confidence interval (CI) (1.22-1.75), P < 0.01) if the adolescent's partner was two or more years older and 1.37 (95% CI (1.16-1.62), P < 0.01) if the partner did not attend the adolescent's school. The odds ratios for having an older partner were also significant and positive for eight different STDs. Partner characteristics were associated with STD infection among American adolescents. Counselling is needed in clinics that serve adolescents to raise awareness of the risk of infection in these relationships and to improve skills in condom negotiation and use.

Adolescent↗

PubMed1991

Effects of home environment on respiratory symptoms and lung function in a general population sample in north Italy.

Effects of indoor pollution exposure were evaluated in a general population sample (n = 3,289) living in the Po River Delta area. Prevalence rates of chronic cough in men and dyspnoea in women were significantly higher in association with the use of bottled gas (propane) for cooking instead of natural gas (methane). Chronic cough and phlegm in men and dyspnoea in women were significantly associated with the use of a stove for heating. When combining type of heating and fuel used, in men a trend toward higher prevalence rates of chronic cough and phlegm was shown in those with stove or fan heating (regardless of the fuel); in women the trend reached statistical significance for dyspnoea. The relationship between stove (regardless of fuel) and decrease in forced expirograms was statistically significant only in women. In multiple logistic models, accounting for independent effects of age, smoking, pack-years, parents' smoking, socio-economic status, body mass index, significantly increased odds ratios were found in males for the associations of: bottled gas for cooking with cough (1.66) and dyspnoea (1.81); stove for heating with cough (1.44) and phlegm (1.39); stove fuelled by natural gas and fan or stove fuelled other than by natural gas with cough (1.54 and 1.66). In females, significantly increased odds ratios were found only for dyspnoea when associated with bottled gas for cooking (1.45), stove for heating (1.46), stove fuelled by natural gas (1.58), stove or fan fuelled other than by natural gas (1.73).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed2002

A study of stopping propensity at matured red light camera T-intersections.

PROBLEM: This paper evaluates the stopping propensity of drivers at matured in-service red light camera (RLC) signalized T-intersections after a number of years of camera operation. METHOD: A special-purpose data logger working in conjunction with loop sensors was used to gather traffic parameters, vehicle stopping/crossing movements, and signal phases at camera (treatment) and noncamera (comparison) approaches. Logistic modeling was employed to determine the stopping/crossing decisions of civilian vehicle drivers in response to the onset of yellow (amber) with traffic and the associated situational and behavioral variables, including their interactions. SUMMARY: The propensity to stop at camera approaches was about 17 times more than at noncamera approaches. This finding strongly affirmed the positive effect of RLC in encouraging drivers to stop. The likelihood to stop was about 6.5 times higher for an approach that faces an opposing right-turn conflict immediately after the onset of red. Higher stopping propensity was also more prevalent during weekdays and in periods of low traffic volumes. IMPACT ON INDUSTRY: The findings provided an objective measure on the effectiveness of RLC that would be useful to evaluate intersections for camera installation as well as on the implementation and operational aspects of RLC program.

Accidents, Traffic↗

PubMed2000

The impact of area deprivation on differences in health: does the choice of the geographical classification matter?

OBJECTIVE: Many studies show the average health status in deprived areas to be poorer and the use of health care to be higher, but there is hardly any information on the impact of the geographical classification on the size of these differences. This study examines the impact of the geographical classification on the clustering of poor health per area and on the size of the differences in health by area deprivation. DESIGN: Data on self reported health regarding 5121 people were analysed using three classifications: neighbourhoods, postcode sectors and boroughs. Multilevel logistic models were used to determine the clustering of poor health per area and the size of the differences in health by area deprivation, without and subsequently with adjustment for individual socioeconomic status. SETTING: General population aged 16 years and over of Amsterdam, The Netherlands. MAIN OUTCOME MEASURES: Self rated health, mental symptoms (General Health Questionnaire, 12-item version), physical symptoms and long term functional limitations. MAIN RESULTS: The clustering of poor health is largest in neighbourhoods and smallest in postcode sectors. Health differences by area deprivation differ only slightly for the three geographical classifications, both with and without adjustment for individual socioeconomic status. CONCLUSIONS: In this study, the choice of the geographical classification affects the degree of clustering of poor health by area but it has hardly any impact on the size of health differences by area deprivation.

Adolescent↗

PubMed1996

Judging hospitals by severity-adjusted mortality rates: the influence of the severity-adjustment method.

OBJECTIVES: This research examined whether judgments about a hospital's risk-adjusted mortality performance are affected by the severity-adjustment method. METHODS: Data came from 100 acute care hospitals nationwide and 11880 adults admitted in 1991 for acute myocardial infarction. Ten severity measures were used in separate multivariable logistic models predicting in-hospital death. Observed-to-expected death rates and z scores were calculated with each severity measure for each hospital. RESULTS: Unadjusted mortality rates for the 100 hospitals ranged from 4.8% to 26.4%. For 32 hospitals, observed mortality rates differed significantly from expected rates for 1 or more, but not for all 10, severity measures. Agreement between pairs of severity measures on whether hospitals were flagged as statistical mortality outliers ranged from fair to good. Severity measures based on medical records frequently disagreed with measures based on discharge abstracts. CONCLUSIONS: Although the 10 severity measures agreed about relative hospital performance more often than would be expected by chance, assessments of individual hospital mortality rates varied by different severity-adjustment methods.

Adult↗

PubMed2003

Analysis of localized erythema using clinical indicators and spectroscopy.

Localized erythema is regularly used as an indicator of post-ischemic events, including reactive hyperemia and Stage I pressure ulcers. The National Pressure Ulcer Advisory Panel definition of a Stage I ulcer includes both visual and nonvisual indicators in part to improve identification in darkly pigmented skin. A prospective, repeated-measures design was used to collect information on pressure-induced erythema that includes reactive hyperemia and Stage I pressure ulcers with an emphasis on distinguishing indicators in light and dark skin The relationships among clinical indicators (skin assessments) and results from tissue reflectance spectroscopy, as well as the clinical utility of spectroscopy for discerning tissue blanching status, were examined in a convenience sample of 76 inpatients and outpatients (95 test/control site pairs). Chi-square analysis and generalized logistic models were used to identify relationships and distinguishing characteristics of erythema. Analysis of variance was used to analyze blanching using spectroscopy. Nonblanching sites were more likely to be persistent erythema (c2=5.3; P = 0.021) but exhibited no relationships to temperature, tissue resilience, or disability. Erythema in subjects with dark skin was more likely to be nonblanching and have poor resilience. Spectrographic analysis of blanching found significant differences across skin pigmentation (P = 0.0001) and blanching status (P = 0.019). These results reinforce the belief that dark skin must be assessed differently than light skin and indicate that clinicians should use persistence of erythema rather than blanching status to judge incipient pressure ulcers. These results validate the use of visual and nonvisual indicators included in the National Pressure Ulcer Advisory Panel Stage I pressure ulcer definition.

Adult↗