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The prognosis of ankle sprains.

We developed a new diagnostic tool for predicting the severity of ankle sprains just after injury. Since hard data obtained by diagnostic imaging techniques are still imperfect, we decided to use data from individual medical history and signs and symptoms that are part of the admission routine. During a three month-period data were collected on thirty-five patients with lateral ankle sprains who visited the first aid department of the University Hospital of Maastricht. Assessments took place at admission and at two and four weeks after injury. Assessors were the first-aid physician, a physiotherapist and the patient. Dependent variables were healed ankle in two and four weeks. Predicting variables were the data obtained at admission by the physician, the physiotherapist and the patient. The ability to predict outcome after two and four weeks was determined in a bivariate analysis, followed by logistic modelling. Accurate prediction of recovery time at admission appeared to be possible. Best two weeks predictor was the modified function score, an accuracy of 97% was achieved. Four weeks prediction was most accurate when function score was used together with the report mark from the doctor and the palpation score (accuracy of 81%).

Activities of Daily Living↗

Early determinants of childhood overweight and adiposity in a birth cohort study: role of breast-feeding.

BACKGROUND: The prevalence of adiposity in childhood is increasing. Is breast-feeding protective as suggested by cross-sectional studies? OBJECTIVE: In a longitudinal birth cohort study, we tested whether breast-feeding for more than 2 months has preventive effects against overweight and adiposity at 6 y. DESIGN: Of 1314 children representing the catchment areas of six delivery units, 918 could be followed up to the age of 6 y. Height, weight, and skin-fold thickness were measured at regular visits. As the criteria of overweight, obesity, and adiposity in the children, the 90th and the 97th percentiles of BMI and skin-fold values were used. Parents with a BMI at or above the 90th percentile, which was 27 kg/m(2) or more, were considered overweight. Infants bottle-fed from birth or breast-fed for less than 3 months were classified as 'bottle-fed' (BO), and those breast-fed for 3 months and more as 'breast-fed' (BR). Univariate comparisons and logistic regression analysis were performed applying SAS 6.12. The final logistic model consisted of the 480 cases for whom complete data for all variables were available. The potential effect of loss to follow-up was analysed by the Cochran-Mantel-Haenzel test: the outcomes were not significantly influenced by loss to follow-up. RESULTS: At birth BMIs were nearly identical in both groups. By 3 months, BO had significantly higher BMIs and thicker skin folds than BR. From 6 months on, compared to BR, a consistently higher proportion of BO children exceeded the 90th and the 97th percentile of BMI and skin-fold thickness reference values. From the age of 4 y to 5 and 6 y, in BO the prevalence of obesity nearly doubled and tripled, respectively. With only minor changes of obesity prevalence in BR, the difference of BMI and skin-fold thickness between groups became statistically significant. Logistic regression analysis revealed that overweight of the mother, maternal smoking during pregnancy, bottle feeding, and low social status remained important risk factors for overweight and adiposity at 6 y of age. CONCLUSION: A maternal BMI of > or =27, bottle-feeding, maternal smoking during pregnancy, and low social status are risk factors for overweight and adiposity at 6 y of age. Early bottle-feeding brings forward the obesity rebound, predictive of obesity in later life.

Body Mass Index↗

Age and gender differences in risk-taking behaviour as an explanation for high incidence of motor vehicle crashes as a driver in young males.

Risk-taking behaviour has been identified as a possible explanation for the high incidence of motor vehicle crashes involving young male drivers. This study examines the extent to which differences in risk-taking behaviour explain the differential crash rates by age and gender. A random sample of 689 adults aged 17-88 were selected from motor vehicle license holders within randomly selected geographical areas across Queensland. Participants completed a questionnaire covering their attitudes towards driving behaviour and general risk-taking behaviour, selected demographic characteristics and self-reported history of road crashes as a driver. Univariate analysis showed that males scored higher means than females in driver aggression and thrill seeking and in their general risk acceptance. Multivariate logistic regression analysis indicated that males were twice as likely (OR 2.46, CI 1.59-3.83) to have reported at least one crash as a driver compared to females and nearly three times as likely (OR 2.88, CI 1.84-4.49) to have reported two or more crashes. Drivers aged 17-29 were also twice as likely (OR 2.31, CI 1.10-4.19) to have reported at least one crash when compared to those aged over 50 years. When risk-taking behaviours were introduced into the logistic model the odds of males (OR 1.70, CI 1.29-3.30) or 17-29 year olds (OR 1.30, CI 0.93-3.91) being involved in at least one crash substantially reduced. An increased risk of a crash as a driver can, in part, be explained by the age and gender differential in risk-taking behaviour. The challenge for public health professionals is to determine suitable strategies to modify risk-taking behaviour in young or male drivers.

Accidents, Traffic↗

A new method with general diagnostic utility for the calculation of immunoglobulin G avidity.

The reference method for immunoglobulin G (IgG) avidity determination includes reagent-consuming serum titration. Aiming at better IgG avidity diagnostics, we applied a logistic model for the reproduction of antibody titration curves. This method was tested with well-characterized serum panels for cytomegalovirus, Epstein-Barr virus, rubella virus, parvovirus B19, and Toxoplasma gondii. This approach for IgG avidity calculation is generally applicable and attains the diagnostic performance of the reference method while being less laborious and twice as cost-effective.

Antibodies, Protozoan↗

Association tests for traits with variable age at onset.

This paper is concerned with testing association between marker genotypes and traits with variable age at onset. Two methods are proposed, one which makes use of both age-at-ascertainment and age-at-onset information, and one which may be applied when only age-at-ascertainment information is available. (Here, by age-at-ascertainment, is meant the subject's age when presence of onset and age at onset are determined; for subjects who have died or are otherwise censored before ascertainment, the censoring time should be used instead). Adjustment for confounding due to population stratification is carried out by conditioning on observed traits and parental genotypes, or, if complete parental genotypes are not available, by conditioning on observed traits and the minimal sufficient statistics under the null hypothesis for the parental genotypes. Proportional hazards regression models and logistic regression models are used to motivate the methods, but correct type I error rates result even if the models are not correct. An illustrative example is described.

Age of Onset↗

Impaired cerebrovascular reactivity as a risk marker for first-ever lacunar infarction: A case-control study.

BACKGROUND AND PURPOSE: Functional assessment of small arteries and arterioles could provide valuable information regarding the extent of diffuse arteriolosclerosis in patients with small-vessel disease. Therefore we attempted to clarify the role of cerebrovascular reactivity (CVR) as a risk marker for first-ever symptomatic lacunar infarction. METHODS: Forty-six patients with lacunar infarction and 46 sex- and age-matched control subjects were prospectively evaluated. Cerebral hemodynamics were studied with transcranial Doppler ultrasonography. CVR was examined by calculating the percent increase in mean flow velocity occurring after 15 mg/kg acetazolamide administration (Diamox test). RESULTS: CVR was significantly (P<0.0001, Student's t test) lower in cases (50.0+/-12. 7%) as compared with control subjects (65.2+/-12.4%). A multiple logistic regression analysis identified male sex (odds ratio [OR] 2. 3, P=0.02), age (OR 3.6, P<0.005), and the presence of lacunar infarction on magnetic resonance imaging (OR 5.3, P<0.001) as significant and independent factors associated with a reduction of CVR. Moreover, a cut-point of 55.6% (sensitivity 67%, specificity 82%) was established as the threshold value for distinguishing between pathological and normal CVR. CVR was significantly (P=0.02) lower in patients with multiple (46.38+/-12.6%) than with single (54. 83+/-11.58%) lacunar infarction. In addition, a trend of negative correlation was found between CVR and the number of lacunar infarctions (r=-0.26, P=0.08). In the multiple logistic model, history of hypertension (OR 7.24; 95% confidence interval 2.95 to 17. 79) and CVR (OR 0.8; 95% confidence interval 0.81 to 0.93) emerge as significant and independent predictors of first-ever lacunar infarction. CONCLUSIONS: These data suggest that impaired CVR is a risk marker for first-ever lacunar infarction.

Acetazolamide↗

Heterosexual transmission of HIV analysed by generalized estimating equations.

A longitudinal analysis of a partner study is compared with a cross-sectional analysis which identify behavioural and biological risk factors for heterosexual transmission of HIV. Using generalized estimating equations (GEEs) a random effects logistic model is used for the longitudinal analysis. These approaches are illustrated by the Edinburgh heterosexual partner study. The longitudinal analysis finds that 'high-risk' sexual practices, unprotected intercourse for HIV and a low CD4 count in the index case significantly increase the risk of HIV transmission. The cross-sectional analysis, however, only indicates 'high-risk' sexual practices as favourable for HIV transmission.

Adolescent↗

Lower plasma vitamin E levels are associated with the frailty syndrome: the InCHIANTI study.

BACKGROUND: The primary biologic mechanism that causes frailty in older persons has never been adequately explained. According to recent views, oxidative stress may be the driving force of this condition. We tested the hypothesis that, independent of confounders, low plasma levels of vitamin E (alpha-tocopherol), the main fat-soluble human antioxidant, are associated with the frailty syndrome in older persons free from dementia and disability. METHODS: The study sample included 827 older (> or =65 years) persons (women, 54%) who participated in a population-based epidemiological study. Frail participants were identified based on the presence of at least three of five of the following features: self-reported weight loss, low energy, slow gait speed, low grip strength, and low physical activity. Participants with none of these features were considered nonfrail, while participants with one or two were considered intermediate frail. Plasma vitamin E levels were determined using reverse-phase high-performance liquid chromatography. Measured confounders included lower extremity muscle strength, cognitive function, diseases, and factors related to vitamin E metabolism. RESULTS: Age- and gender-adjusted levels of vitamin E decreased gradually from the nonfrail to the frail group (p for trend =.015). In the logistic model adjusted for multiple potential confounders, participants in the highest vitamin E tertile were less likely to be frail than were participants in the lowest vitamin E tertile (odds ratio, 0.30; 95% confidence interval, 0.10-0.91). CONCLUSIONS: Our findings show an association between low circulating levels of one of the most important components of the human antioxidant system and the presence of frailty.

Aged↗

The risk to develop NIDDM is related to the fatty acid composition of the serum cholesterol esters.

This investigation was undertaken to study whether the risk to develop non-insulin-dependent diabetes mellitus (NIDDM) among 50-year-old men during a 10-year follow-up period was related to the fatty acid composition of their serum cholesterol esters. There were highly significant differences in the initial health survey between the fatty acid composition in serum in subjects who remained normoglycemic (n = 1,753) and in those who later developed NIDDM (n = 75). The main differences were that the latter had higher proportions of saturated fatty acids and palmitoleic acid (16:1 omega-7), a low proportion of linoleic acid (18:2 omega-6), and a relatively high content of gamma-linolenic (18:3 omega-6) and dihomo-gamma-linolenic (20:3 omega-6) acids in the serum cholesterol esters. The picture was similar also after adjusting for differences in body mass index. In a logistic model, a high proportion of dihomo-gamma-linolenic acid remained a significant contributor to the development of diabetes, along with the height of the insulin index, the blood glucose concentration at 60 min, and the fasting insulin concentration. The increased risk to develop NIDDM related to the serum cholesterol ester fatty acid composition may be mediated by diet and/or genetic factors.

8,11,14-Eicosatrienoic Acid↗

Risk factors for distal symmetric neuropathy in NIDDM. The San Luis Valley Diabetes Study.

OBJECTIVE: To investigate risk factors for distal symmetric (sensory) neuropathy among prevalent cases of non-insulin-dependent diabetes mellitus (NIDDM) in a population-based study in southern Colorado. RESEARCH DESIGN AND METHODS: Prevalent neuropathy was identified in 77 of 277 people with NIDDM by a standardized history and neurologic examination. Fifteen known or suspected risk factors for neuropathy were determined without knowledge of neuropathy status. RESULTS: Older age at examination, longer duration of diabetes, higher glycohemoglobin percentage, lower fasting C-peptide, insulin use, and presence of retinopathy and nephropathy (microalbumin > or = 200 micrograms/ml) were all significantly associated with neuropathy. Sex, ethnicity (Hispanic versus non-Hispanic white), height, systolic blood pressure, peripheral vascular disease, cigarette and alcohol use, and serum lipid levels were not significantly associated with neuropathy. In a multivariate logistic model, increasing age (odds ratio [OR] = 1.3, 95% confidence interval [CI] = 1.1-1.6), longer duration of diabetes (OR = 1.3, CI = 1.0-1.6), increased glycohemoglobin percentage (OR = 1.5, CI = 1.1-2.1), and insulin use (OR = 2.8, CI = 1.3-6.1) were associated with neuropathy. Retinopathy (OR = 3.0, CI = 1.2-7.7), but not nephropathy, was important when added to this model. CONCLUSIONS: Worse glycemic control and insulin use were independently associated with neuropathy in people with NIDDM. Whether insulin use represents another marker for severity of the metabolic disturbance or is an independent risk factor for neuropathy requires further study. We could not confirm associations of neuropathy with height, with nephropathy, or with retinopathy, independent of duration of diabetes.

Adult↗

Cesarean section as a cause of chronic pelvic pain.

OBJECTIVE: To determine if the history of cesarean section was associated with chronic pelvic pain, independent of the presence of other conditions such as pelvic adhesions, endometriosis, sequelae of pelvic inflammatory disease, leiomyoma and pelvic varices. METHODS: Retrospective case-control study conducted on 199 patients consecutively admitted from January 1998 to January 2000, 116 of them submitted to laparoscopy for the diagnosis of chronic pelvic pain and 83 asymptomatic patients submitted to tubal ligation by laparoscopy. A logistic regression analysis was used to verify the association between chronic pelvic pain and the history of previous cesarean section. RESULTS: In women with chronic pelvic pain, a history of cesarean section was observed in 67.2% of cases, adhesions in 51.7%, endometriosis in 33.6%, sequelae of pelvic inflammatory disease in 31.9%, leiomyoma in 6.9% and pelvic varices in 11.2%. In asymptomatic women, a history of cesarean section was observed in 38.5%, adhesions in 24.1%, endometriosis in 9.6%, sequelae of pelvic inflammatory disease in 4.8%, leiomyoma in 7.2% and pelvic varices in 3.6%. In a logistic model, chronic pelvic pain was associated with a history of cesarean section (O.R.=3.7), as well as with endometriosis (O.R.=8.5), sequelae of pelvic inflammatory disease (O.R.=10.5). CONCLUSIONS: In the present study cesarean section was associated with chronic pelvic pain. This fact may be the cause of a public health problem in the coming years, due to the raised rates of cesarean section in Brazilian women.

Adult↗

Perioperative predictors of morbidity following hepatic resection for neoplasm. A multivariate analysis of a single surgeon experience with 105 patients.

OBJECTIVE: Factors that predict mortality or morbidity risk in consecutive hepatic resections for neoplasm were examined, with controlled variables of surgical technique and experience. SUMMARY BACKGROUND DATA: Hepatic resection has become the therapy of choice for the management of metastatic or primary neoplasms of the liver. Although mortality for this procedure has steadily decreased, associated morbidity remains high. METHODS: One hundred five patients undergoing hepatic resection for malignancy over a 4-year period by a single surgeon to identify preoperative, intraoperative, or postoperative predictors of morbid outcomes were studied. Variables were analyzed using multiple regression in a stepwise, logistic model. RESULTS: Sixty-day hospital mortality was 2.8%, with morbidity occurring in 33%. A significant preoperative predictor of morbidity was serum bilirubin (p > 0.005). Notably, preoperative renal function, or medical illness, did not increase morbid risk. Operative variables increasing risk included extent of resection, blood loss, and operative time (p > 0.005). CONCLUSIONS: Complex hepatic resection can be performed with low mortality, and serum bilirubin is the single most powerful predictor of postoperative complication.

Bilirubin↗

Synergistic effects of prothrombotic polymorphisms and atherogenic factors on the risk of myocardial infarction in young males.

Several recent studies evaluated a possible effect of the prothrombotic polymorphisms such as 5,10 methylenetetrahydrofolate reductase (MTHFR) nt 677C --> T, factor V (F V) nt 1691G --> A (F V Leiden), and factor II (F II) nt 20210 G --> A on the risk of myocardial infarction. In the present study, we analyzed the effect of these prothrombotic polymorphisms, as well as apolipoprotein (Apo) E4, smoking, hypertension, diabetes mellitus, and hypercholesterolemia, on the risk of myocardial infarction in young males. We conducted a case-control study of 112 young males with first acute myocardial infarction (AMI) before the age of 52 and 187 healthy controls of similar age. The prevalences of heterozygotes for F V G1691A and F II G20210A were not significantly different between cases and controls (6.3% v 6.4% and 5.9% v 3.4% among cases and controls, respectively). In contrast, the prevalence of MTHFR 677T homozygosity and the allele frequency of Apo E4 were significantly higher among patients (24.1% v 10.7% and 9.4% v 5.3% among cases and controls, respectively). Concomitant presence of hypertension, hypercholesterolemia, or diabetes and one or more of the four examined polymorphisms increased the risk by almost ninefold (odds ratio [OR] = 8.66; 95% confidence interval [CI], 3.49 to 21.5) and concomitant smoking by almost 18-fold (OR = 17.6; 95% CI, 6.30 to 48.9). When all atherogenic risk factors were analyzed simultaneously by a logistic model, the combination of prothrombotic and Apo E4 polymorphisms with current smoking increased the risk 25-fold (OR = 24.7; 95% CI, 7.17 to 84.9). The presented data suggest a synergistic effect between atherogenic and thrombogenic risk factors in the pathogenesis of AMI, as was recently found in a similar cohort of women.

Activated Protein C Resistance↗

Age-acquired resistance and predisposition to reinfection with Schistosoma haematobium after treatment with praziquantel in Mali.

The effect of age, previous intensity of infection, and exposure on reinfection with Schistosoma haematobium after treatment was studied in a cohort of 468 subjects six years of age and over living in an irrigation scheme area in Mali. Prevalence and intensity of S. haematobium infection were measured each year between 1989 and 1991, but the reinfection study period was restricted to the last year of the follow-up. Observations were made at the principal water contact sites where the number of Bulinus truncatus shedding furcocercous cercariae was recorded. A cumulative index of exposure taking into account time, duration and type of contact, and malacologic data was calculated for each subject. Univariate analysis showed that the reinfection risk decreased with age and increased with exposure and pretreatment intensity. These results were confirmed by fitting a logistic model that showed that this risk was seven times lower among those 15 years of age and older than among the 6-14-year-old children, while linear trends with exposure to infection and pretreatment intensity were significant. This study supports the concept of an age-acquired resistance to reinfection and is in favor of a predisposition to infection that raises the question of a genetic factor controlling susceptibility/resistance to S. haematobium infection.

Adolescent↗

Risk factors for delayed immunization in a random sample of 1163 children from Oregon and Washington.

Despite extensive study of vaccine safety and decades of effort to immunize infants and toddlers, little is known about the comprehensiveness of vaccine coverage in US children younger than 2 years of age. Provider and parent data from a population-based sample of 1163 children from two states were analyzed to assess coverage rates at three ages and to evaluate characteristics of children and their families that predict failure to immunize on schedule. Overall, 78% of the children had received their first dose of diphtheria and tetanus toxoids with pertussis vaccine (DTP) and their first dose of oral poliovirus (OPV) by 92 days of age. Similarly, 77% had received their third dose of DTP and their second dose of OPV by their first birthday. However, by their second birthday only 60% had received the full series of four doses of DTP, three doses of OPV, and one dose of the measles, mumps, and rubella vaccines. When considered singly, several variables including child birth order, family income, maternal education, and marital status significantly predicted failure to immunize on schedule. In multivariate logistic models, only birth order and maternal education consistently predicted vaccine status at each of the three ages. Compared with first-born children, those who were later-born were 1.7 times more likely to be incompletely immunized at 2 years of age (95% confidence interval: 1.2, 2.3). Children of more educated mothers were significantly less likely to be underimmunized at all ages.(ABSTRACT TRUNCATED AT 250 WORDS)

Birth Order↗

Early developmental history and pediatric posttraumatic stress disorder.

OBJECTIVE: To determine which factors from the early developmental histories of maltreated children are associated with the risk of developing posttraumatic stress disorder (PTSD). DESIGN: Retrospective cohort analytic study. SETTING: A county juvenile/family court (not a criminal court). SAMPLE: The sample consisted of 117 severely maltreated children, aged 5 to 12 years, whose maltreatment was so severe that they were removed from parental custody. Forty-one (35%) of these children met criteria of the Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition, for PTSD. MAIN OUTCOME MEASURES: Individual developmental and temperament-independent variables were used to compare children with PTSD and the maltreated children who did not reach PTSD inclusion criteria. The child's PTSD status was the primary dependent variable. RESULTS: Variables representing the three factors from the early developmental history, along with markers for sex and race (black vs other), were entered into a logistic regression, with PTSD status as the outcome variable. Indicators of five different types of child maltreatment were also entered as predictors, to control for previously discovered effects associated with the type of trauma suffered by the children. This analysis disclosed that, while we controlled for the other predictors, one of the developmental factors remained statistically significant, one was marginally significant (P = .07), and one made no contribution toward predicting the probability of PTSD. Sex did not make a significant contribution to the logistic model, but being black continued to be associated with a lower probability of developing PTSD. CONCLUSIONS: We conclude that PTSD may be caused by factors discernible in the first year of life that leave a maltreated child vulnerable to this disorder. These include birth weight less than 2.25 kg, jaundice, vomiting, diarrhea, infections, sleep problems, frequent crying, poor weight gain, fussiness, jumpiness, and distress when moved. The seemingly protective effect of being black was an unexpected, although provocative, finding whose interpretation will require further investigation.

Child↗

Socio-economic status and binge drinking in Israel.

Modern Israeli society is comprised primarily of two nationality groups-Jews and Arabs, with disparate religious and cultural attitudes toward alcohol drinking. We recently described higher rates of past-month drinking among Jewish adults, although Arabs who drink were more likely to report binge drinking. The goal of the present study is to examine the relationship between binge drinking and socio-economic status (SES) among Arab and Jewish adults in Israel. Data from a 1995 nationally representative household survey on drug and alcohol use were analyzed. Participants included male and female Arabs (n=982) and Jews (n=4,972) aged 18-40 living in Israel. SES was assessed using education, household income, and occupation. The prevalence of binge drinking was highest among Arab men (21.4%) followed by Jewish men (15.2%), Arab women (7.3%), and Jewish women (4.0%). Prevalence rates and odds ratios (ORs) from logistic models controlling for age, gender, marital status and religiosity show that increased household income and occupation are associated with increased binge drinking among Arabs (OR>2.0) and decreased binge drinking among Jews (OR congruent with 0.6). Higher educational achievement was protective against binge drinking in both nationality groups. Varied results for income and occupation, and education indicate the need to examine the association between each SES indicator and alcohol consumption independently, especially in culturally diverse populations.

Adolescent↗

Hypertension is related to the degradation of dietary frying oils.

BACKGROUND: The family kitchen resembles an uncontrolled laboratory experiment, and some discrepancies in the relation between the risk of hypertension and dietary fat may be partly due to the manipulation to which the fats were subjected. OBJECTIVE: We investigated whether deterioration in the quality of the cooking oils in the family household contributes to the risk of high blood pressure. DESIGN: The study was cross-sectional. Anthropometric measurements were obtained for 1226 persons aged 18-65 y who were selected randomly from the municipal census of Pizarra, Spain. An oral-glucose-tolerance test was given to 1020 of these persons. Samples of the cooking oil being used were taken from the kitchens of a random subset of 538 persons. The concentrations of polar compounds and polymers were used as markers of the deterioration of the oils. The strength of association between variables was measured by calculating the odds ratio from logistic models. RESULTS: Hypertension was strongly associated with obesity and was influenced by sex, diabetes, and age. The presence of excess polar compounds in the cooking oil and the use of sunflower oil were related to the risk of hypertension, whereas the concentration of monounsaturated fatty acids in the serum phospholipids was negatively related to this risk. These associations remained after inclusion in the models of age, sex, obesity, and the presence of carbohydrate metabolism disorder. CONCLUSIONS: The risk of hypertension is positively and independently associated with the intake of cooking oil polar compounds and inversely related to blood concentrations of monounsaturated fatty acids.

Adolescent↗