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PubMed2003

Maternal fish consumption and infant birth size and gestation: New York State Angler Cohort Study.

BACKGROUND: The scientific literature poses a perplexing dilemma for pregnant women with respect to the consumption of fish from natural bodies of water. On one hand, fish is a good source of protein, low in fat and a rich source of other nutrients all of which have presumably beneficial effects on developing embryos and fetuses. On the other hand, consumption of fish contaminated with environmental toxicants such as polychlorinated biphenyls (PCBs) has been associated with decrements in gestation and birth size. METHODS: 2,716 infants born between 1986-1991 to participants of the New York State Angler Cohort Study were studied with respect to duration of maternal consumption of contaminated fish from Lake Ontario and its tributaries and gestation and birth size. Hospital delivery records (maternal and newborn) were obtained for 92% of infants for the ascertainment of gestation (weeks), birth size (weight, length, chest, and head circumference) and other known determinants of fetal growth (i.e., maternal parity, history of placental infarction, uterine bleeding, pregnancy loss or cigarette smoking and infant's race, sex and presence of birth defect). Duration of maternal fish consumption prior to the index infant's birth was categorized as: none; 1-2, 3-7, 8+ years, while birth weight (in grams), birth length (in centimeters), and head and chest circumference (in centimeters) were left as continuous variables in multiple linear regression models. Birth size percentiles, ponderal indices and head to chest circumference ratios were computed to further assess proportionality and birth size in relation to gestational age. RESULTS: Analysis of variance failed to identify significant mean differences in gestation or any measure of birth size in relation to duration of maternal lifetime fish consumption. Multiple linear regressions identified gestational age, male sex, number of daily cigarettes, parity and placental infarction, as significant determinants of birth size. CONCLUSIONS: The results support the absence of an adverse relation between Lake Ontario fish consumption and reduced birth size as measured by weight, length and head circumference. Biological determinants and maternal cigarette smoking during pregnancy remain important determinants of birth size.

Birth Weight↗

PubMed2006

The economic costs of congenital bilateral permanent childhood hearing impairment.

OBJECTIVE: The objective of this study was to estimate the economic costs of bilateral permanent childhood hearing impairment (PCHI) in the preceding year of life for children aged 7 to 9 years. METHODS: A cost analysis was conducted by using a birth cohort of children born between 1992 and 1997 in 8 districts of Southern England, of which half had been born into populations exposed to universal newborn screening (UNS). Unit costs were applied to estimates of health, social, and broader resource use made by 120 hearing-impaired children and 63 children in a normally hearing comparison group. Associations between societal costs per child and severity of hearing impairment, language ability score, exposure to UNS, and age of confirmation were analyzed, including adjustment for potential confounders in a linear regression model. RESULTS: The mean societal cost in the preceding year of life at 7 to 9 years of age was 14092.5 pound sterling for children with PCHI, compared with 4206.8 pound sterling for the normally hearing children, a cost difference of 9885.7 pound sterling. After adjusting for severity and other potential confounders in a linear regression model, mean societal costs among children with PCHI were reduced by 2553 pound sterling for each unit increase in the z score for receptive language. Using similar regression models, exposure to a program of UNS was associated with a smaller cost reduction of 2213.2 pound sterling, whereas costs were similar between children whose PCHI was confirmed at <9 or >9 months. CONCLUSIONS. The study provides rigorous evidence of the annual health, social, and broader societal cost of bilateral PCHI in the preceding year of life at 7 to 9 years of age and shows that it is related to its severity and has an inverse relationship with language abilities after adjustment for severity.

Child↗

PubMed1993

3-D anatomy of Scarpa's ganglion and surrounding structures.

We reconstructed in three dimensions, and measured by a computer-aided method developed by us, Scarpa's ganglion and surrounding important anatomical structures in 7 normal human temporal bones obtained from 7 individuals aged 7 days to 72 years. We found that this ganglion is shaped like an hourglass and lies with its superior part directed anterosuperolaterally, and its inferior part posteroinferomedially; these two parts are connected by the isthmus ganglionaris. Although the dimensions of the parts of the ganglion varied, such a structure was distinguishable in all the specimens we studied. The volume of the ganglion was found to be relatively consistent in these postnatal specimens; although the width and height of the ganglion varied, they were inversely correlated with each other (linear regression analysis, p < 0.05). We did note, however, some postnatal increase in the distance from the ganglion to its neighboring structures. We also identified a significant correlation between the width of the ganglion and the length of the internal auditory canal and the distance from the ganglion to the vestibular endorgans in any given specimen (linear regression analysis, p < 0.05). These results suggest that although the volume of Scarpa's ganglion does not change after birth, its shape does change with the growth of the individual temporal bone.

Adolescent↗

PubMedDate not supplied

[Correlation of age, IGF-1 serum levels, muscular mass index and their influence as determinants of isokinetic variables in patients with osteoporosis].

INTRODUCTION: Bone and skeletal muscle mass loss is related to age. Mechanisms by which they interact have not been well established. OBJECTIVE: To establish a relationship of age with serum levels of IGF-1, skeletal muscle and appendicular muscle mass index, and their influence in isokinetic parameters in osteoporotic female patients. MATERIAL AND METHODS: Pearson correlation coefficient and linear regression analyses were used. RESULTS: There were 38 patients with a mean age of 65.16 years (range: 50-84 years), mean appendicular skeletal mass index (ASMI) of 6.3 kg/m2 (range: 4.3-8.3) and mean skeletal mass index (SMI) of 12.4 kg/m2 (range: 9.6-15.7), mean serum IGF-1 levels of 82.97 ng/ml (range: 22-177). Linear regression predicted hip mineral bone density by SMI (p = 0.19) and age (p = 0.017, r = 0.50). Some isokinetic parameters had a positive correlation for work with age. Knee acceleration time had a positive correlation with age. CONCLUSIONS: Osteoporosis and sarcopenia may have related pathophysiologic mechanisms. Growth factor study must include the influence of sex hormones. Some isokinetic parameters are determined by the predominant muscle fiber, skeletal mass index and age.

Age Factors↗

PubMed2000

Mildly elevated serum creatinine concentration correlates with the extent of coronary atherosclerosis.

Mildly elevated serum creatinine concentration was proposed to be a marker for increased risk of cardiovascular disease mortality. The aim of our prospective study was to evaluate a possible association between serum creatinine concentration and extent of coronary atherosclerosis together with conventional risk factors for atherosclerosis. Serum creatinine concentration was measured in 40 male patients without overt renal or ischemic renal disease (mean age 53 +/- 7 years) with stable or unstable angina undergoing routine coronary arteriography. The extent of coronary atherosclerosis was assessed by Gensini score. In univariate linear regression analysis Gensini score significantly correlated with serum concentrations of apolipoprotein AII (r=-0.3242, P<0.05) and creatinine (r=+0.3194, P<0.05), but not with serum concentrations of lipids (total, low- and high-density lipoprotein cholesterol, triglycerides), other apolipoproteins (apo B, apo AI), lipoprotein(a), autoantibodies to oxidatively modified low-density lipoprotein or age, weight and status of smoking, diabetes or hypertension. Multivariate linear regression analysis revealed that elevated serum creatinine was associated with the extent of coronary atherosclerosis independently of conventional risk factors for atherosclerosis. Mildly elevated serum creatinine was probably the marker of generalised vascular disease denoting early nephrovasculopathy in correlation with established atherosclerotic risk factors.

Cardiac Catheterization↗

PubMed2001

Effect of ischemic stroke on the dynamic beat-to-beat QT-RR relationship.

The ECGs of 26 patients following ischemic stroke and 18 control patients with various orthopedic problems, all without primary heart disease, were examined to characterize the dynamic behavior of uncorrected QT interval in relation to changing RR interval during physiotherapy effort. ECG waveforms were analyzed to extract beat-to-beat QT and RR intervals. Based on performing multiple cross-correlations, the relationship between the RR and QT intervals was calculated using the following general formula QTi = c RRib-1. Linear regression was performed on the logarithms of QT and RR measurements to estimate the constant (a = log c) and the slope (b) values, reflecting the dynamic change of QT during physiotherapy effort. Having these two values, the dynamic QT extrapolated to a heart period of 1 second (QTcd) was calculated. It was found that the mean slope (b) of the linear regression line in the ischemic stroke group was significantly lower than in the control group (0.26 +/- 0.08 vs 0.33 +/- 0.08, P < 0.02), and the constant (a) was significantly higher (1.83 +/- 0.21 for the ischemic stroke vs 1.61 +/- 0.23 for the controls, P < 0.002). No significant difference was found in QTcd values between the two groups (386 +/- 27 ms for the ischemic stroke vs 392 +/- 25 ms for the controls, P > 0.05). In conclusion, hemispheric brain infarction seems to result in alteration in the autonomic activity during exercise manifesting itself as distorted dynamic behavior of the QT interval.

Aged↗

PubMed2001

Daily assessment of severity of illness and mortality prediction for individual patients.

OBJECTIVE: To refine the prognosis of critically ill patients using a statistical model that incorporates the daily probabilities of hospital mortality during the first week of stay in the intensive care unit (ICU). DESIGN: Prospective inception cohort. SETTING: Fifteen adult medical and surgical ICUs in Spain. PATIENTS: A total of 1,441 patients aged > or =18 yrs who were consecutively admitted from April 1, 1995, through July 31, 1995. INTERVENTIONS: Prospective data collection during the stay of the patient in the ICU. Data collected included vital status at hospital discharge as well as all variables necessary for computing the Mortality Probability Models II system at admission and during the first 7 days of stay in the ICU. MEASUREMENTS AND MAIN RESULTS: Four logistic regression models were obtained. These models contained survival status at hospital discharge as a dependent variable and the following explanatory variables: (model 1) only the probability of dying at admission; (model 2) only the probability of dying during the current day; (model 3) the probability of dying at admission and during the current day; and (model 4) the probabilities of dying at admission and during the previous and current days. Models were evaluated using the Hosmer-Lemeshow statistic and the area under the receiver operating characteristic curve. For survivor and nonsurvivor patients, mortality probabilities obtained using the aforementioned models were compared using linear regression and the paired Student's t-test. Although severity at admission was a statistically significant variable, models 2 and 3 produced almost the same probabilities of hospital mortality, as shown with the linear regression and paired Student's t-test results. CONCLUSIONS: To have an accurate measurement of the prognosis, it is necessary to update the severity measure. The best estimate of hospital mortality was the probability of death on the current day. Severity at admission and at previous days did not improve the assessment of prognosis.

Adult↗

PubMed2004

Which factors are related to the presence of atherosclerosis in rheumatoid arthritis?

OBJECTIVE: An accelerated progression of atherosclerosis may contribute to the increased mortality due to cardiovascular disease reported in rheumatoid arthritis (RA). The aim of this study was to identify variables, related to disease onset as well as to disease progression, of importance for the presence of atherosclerosis, as diagnosed by B-mode ultrasonography, in patients with medium-term RA. The results are based on the co-analysis of retrospective data as well as cross-sectional data. The impact of RA per se on atherosclerosis was evaluated relative to age- and sex-matched controls. METHODS: Thirty-nine RA patients, with a maximum age of 65 years, who had previously been included in a large retrospective cohort study, were assessed by duplex scanning after a disease duration of 19-23 years. In the present study, factors identified in the two earlier studies were assessed for their potential relationship with intima-media wall thickness (IMT) of the common carotid artery (CCA), and the presence and grade of atherosclerotic plaques of the CCA and the common femoral artery, in regression models. The candidate co-variates were: variables reflecting inflammatory activity at disease onset and at the time of ultrasound assessment, established cardiovascular risk factors, pharmacological treatment [corticosteroids, disease-modifying anti-rheumatic drugs (DMARDs)], and the presence of complications and co-morbidity identified during disease progression, as well as lipid levels, anti-lipid antibodies, haemostatic factors, and markers of immune activation measured at ultrasound assessment. RESULTS: In patients with RA, analysis of simple linear regression models revealed those variables significantly associated with IMT-CCA to be age, tissue plasminogen activator (tPA) antigen, cholesterol, low density lipoprotein (LDL)-cholesterol, triglycerides, and atherosclerotic plaques while neither inflammatory status at disease onset, traditional cardiovascular risk factors, or pharmacological treatment during disease had any significant impact on IMT. In an estimated multiple linear regression model, variables associated with increasing log of IMT-CCA were the log of cholesterol and of soluble intracellular adhesion molecule 1 (sICAM-1), while methotrexate treatment tended to have a decreasing effect. In simple binary logistic regression, atherosclerotic plaques were associated with age, IMT-CCA, smoking, and the levels of sICAM-1, sE-selectin, interleukin-2 soluble receptor alpha (IL-2sRalpha), plasminogen activator inhibitor-1 (PAI-1) mass, cholesterol, LDL-cholesterol, and the LDL/high density lipoprotein (HDL) ratio. A multiple approach indicated that plaques were associated with age, cholesterol, and sE-selectin. Severe plaques were associated with LDL-cholesterol and disease duration. Logistic regression in the age- and sex-matched case-control study revealed that IMT-CCA was, together with the D-dimer, associated with RA per se. CONCLUSION: Levels of lipids and adhesion molecules were associated with the presence of atherosclerosis in RA. IMT-CCA was associated with RA per se. Disease duration could predict severe atherosclerotic plaques. Treatment with methotrexate seemed to decrease the IMT-CCA.

Adult↗

PubMed2002

Is 24-h sperm motility a useful IVF measure when male infertility is not apparent?

OBJECTIVE: To examine the relationship of 24-h sperm motility between post insemination and fertilization in vitro, in a population with no apparent semen abnormalities. A retrospective study from July 1998 to June 2000. MATERIAL AND METHODS: Four hundred and seventy-one consecutive in-vitro fertilization (IVF) cycles for which the primary diagnosis was not male infertility (total motility count > 40 x 106) were studied. Linear regression was used to examine the general relation between 24-h sperm motility and IVF. The cohort with 0% 24-h motility was compared with all other cycles using the t-test and the chi2-test. Test quality was assessed using the positive likelihood ratio. RESULTS: Overall fertilization was 58 +/- 16%. There were 45/471 cycles (9.5%) with zero fertilization. Linear regression of percent fertilization vs. 24-h motility showed no relationship (r = 0.01). The cohort with 0% 24-h motility had a lower fertilization rate 29 +/- 19% (P = 0.05), and had a higher incidence of no fertilization 7/21 (P = 0.01). The positive likelihood ratio was 4.6. CONCLUSIONS: Zero 24-h motility indicates occult male infertility, and a positive result indicates a fair to good test. Overall there was no relationship between sperm survival at 24 h post insemination and fertilization in vitro. However, 0% 24-h sperm motility was associated with reduced fertilization

Female↗

PubMed1999

Estimation of desflurane concentration using isoflurane channel in optical infrared analyzer.

PURPOSE: To estimate desflurane concentration on the isoflurane channel in an optical infrared analyzer using a simple regression equation. METHODS: Desflurane in concentrations of 0% to 3% in 0.5% increments and 3% to 12% in 1% increments in 2 L.min-1 oxygen was delivered simultaneously to an Ohmeda 5250 RGM desflurane channel, an Ohmeda 5250 RGM isoflurane channel, and a Datex Capnomac Ultima isoflurane channel at room temperature and atmospheric pressure. For each concentration increment, the displayed gas concentrations were recorded. By comparing the readings from the desflurane channel of Ohmeda RGM and the isoflurane channels from Ohmeda RGM and Datex Capnomac Ultima respectively, the linear regression relationship and the slope of the fitted line (conversion factor) between two channels were obtained. Similar measurements were performed using 2 L.min-1 mixture of nitrous oxide 50% and oxygen 50%. The measurements were repeated with different monitors three months later. RESULTS: All four analysers tested were linear (r2 > 0.9) for measuring desflurane using isoflurane channels over the range of concentrations studied on two different days. The accuracy of the estimation using the mean conversion factor of the four monitors was within 10% error from the readings of the commercially available desflurane channel analyzer. There was no noticeable effect on the slope (conversion factor) of the linear regression with O2 100% or 50/50 mixture of N2O and O2. CONCLUSION: The concentration of desflurane can be estimated by a simple conversion factor using an isoflurane channel of an infrared system.

Analysis of Variance↗

PubMed2006

Factors associated with decreased cerebral blood flow in congestive heart failure secondary to idiopathic dilated cardiomyopathy.

Cerebral blood flow (CBF) is decreased and cognitive dysfunction develops in the advanced stages of heart failure. However, few data are available regarding the factors associated with decreased CBF. Fifty-two patients with advanced congestive heart failure (CHF) secondary to idiopathic dilated cardiomyopathy (ejection fraction <or=35%) and 10 healthy volunteers were included in this study. Echocardiography and symptom-limited bicycle exercise testing were performed. Global CBF was measured by radionuclide angiography. Global CBF was 19% less in patients with CHF than in controls (p <0.01). Such reduced CBF became normalized in 4 patients with CHF who underwent cardiac transplantation. In a univariate linear regression analysis, global CBF was significantly associated with New York Heart Association functional class, disease duration, atrial fibrillation, serum B-type natriuretic peptide level, the early mitral velocity/early diastolic annular velocity ratio, and pulmonary artery systolic pressure. Global CBF was not found to be associated with the ejection fraction, peak oxygen consumption, or anaerobic threshold. In a stepwise multivariate linear regression analysis, serum B-type natriuretic peptide level (p = 0.047) and New York Heart Association functional class (p = 0.003) were significantly related to global CBF (global CBF = 48.373 - 0.05 x serum B-type natriuretic peptide level - 3.283 x New York Heart Association functional class; r(2) = 0.401). In conclusion, CBF is decreased in patients with CHF, which may be used to predict disease severity and chronicity.

Adult↗

PubMed1998

Relationships between isoinertial lumbar dynamometry parameters and demographic parameters in chronic low back pain patients.

The purpose of this study was to investigate which demographic parameters are most important in relation to lumbar dynamometry performance in patients with chronic low back pain (LBP). Forty-five chronic LBP patients participated in this study. Gender, age, weight and height were determined and a lumbar dynamometry measurement was carried out, using the Isostation B200. Student's t-test, ANOVA techniques and correlation coefficients were used to investigate the relationships between each demographic parameter and lumbar dynamometry performance. Stepwise multiple linear regression analyses were performed afterwards to determine which demographic parameters are most important in relation to lumbar dynamometry performance. Results indicate significant relationships (1) between gender, height, weight and all lumbar dynamometry parameters and (2) between age and three of the six isometric torque parameters. No significant relationship was found between age and maximum velocity parameters. Results of the stepwise multiple linear regression analyses show that the demographic parameters explain 27-47% of the variance in maximum isometric strength parameters and 19-25% of the variance in maximum velocity parameters. Gender is the most important demographic parameter, being related to nearly all maximum isometric torque parameters (percentage explained variance 6-37%) and height is the only important demographic parameter related to the velocity parameters (percentage explained variance 19-25%). Weight and age account for only a small amount of variance in lumbar dynamometry parameters (percentage explained variance 5-7%), meaning that these parameters are non-relevant predictors.

Adult↗

PubMedDate not supplied

Determination of pirlimycin residue in milk by liquid chromatographic analysis of the 9-fluorenylmethyl chloroformate derivative.

A procedure to determine pirlimycin residues in bovine milk was developed. Pirlimycin was extracted from milk after protein precipitation and 2 stages of liquid-liquid partitioning. The extract was evaporated to dryness, redissolved in dilute base, and derivatized with 9-fluorenylmethyl chloroformate (Fmoc) to impart a chromophore for ultraviolet (UV) detection. The derivatized extract was analyzed by reversed-phase liquid chromatography (LC). Pirlimycin concentration was calculated from the peak height of the extract by using a linear regression standard curve prepared from a series of derivatized standards. The procedure's performance in the range of the regulatory tolerance (0.4 ppm) was validated by replicate analysis of control, fortified control, and residue-incurred bovine milk. Average recoveries at 0.2, 0.4, and 0.8 ppm were 91, 88, and 87%, respectively, and coefficients of variation were 5, 4, and 1%, respectively. Overall recovery for all samples was 89%, with 4% coefficient of variation. Linear regression analysis of LC/UV results versus results from a previously published LC/mass spectrometric assay gave a slope of 0.95, with a correlation coefficient of 0.98.

Animals↗

PubMedDate not supplied

Preterm deliveries among women with MacDonald cerclage performed due to cervical incompetence.

OBJECTIVE: The study was aimed to assess the impact of obstetric risk factors for preterm delivery among women with MacDonald cerclage performed due to cervical incompetence. STUDY DESIGN: A cohort study was conducted including all patients with MacDonald cerclage performed at 12-14 weeks gestation due to cervical incompetence (n = 793). Deliveries occurred between the years 1988 and 2002 in a University Medical Center. A multiple linear regression model was used to assess the impact of maternal characteristics as well as pregnancy complications on the length of pregnancy. RESULTS: The following factors were found to be associated with preterm delivery among these patients, in the univariate analysis: nulliparity, fertility treatments, severe preeclampsia, second-trimester bleeding, premature rupture of membranes (PROM), chorioamnionitis and placental abruption. Using a multiple linear regression model, with backward elimination, the impact of these variables on the length of pregnancy was assessed (R(2) = 0.33, p < 0.001). The mean gestational age at birth among patients without risk factors was 38.1. Second-trimester bleeding reduced gestational age by 6.4 weeks, chorioamnionitis by 5.6 weeks, placental abruption by 5.1 weeks, PROM by 3.2 weeks and severe preeclampsia by 2.4 weeks. CONCLUSIONS: Second-trimester bleeding, chorioamnionitis, placental abruption, PROM and severe preeclampsia are ominous signs for preterm delivery among patients with MacDonald cerclage performed due to cervical incompetence.

Adult↗

PubMed2004

A simple approach to power and sample size calculations in logistic regression and Cox regression models.

For a given regression problem it is possible to identify a suitably defined equivalent two-sample problem such that the power or sample size obtained for the two-sample problem also applies to the regression problem. For a standard linear regression model the equivalent two-sample problem is easily identified, but for generalized linear models and for Cox regression models the situation is more complicated. An approximately equivalent two-sample problem may, however, also be identified here. In particular, we show that for logistic regression and Cox regression models the equivalent two-sample problem is obtained by selecting two equally sized samples for which the parameters differ by a value equal to the slope times twice the standard deviation of the independent variable and further requiring that the overall expected number of events is unchanged. In a simulation study we examine the validity of this approach to power calculations in logistic regression and Cox regression models. Several different covariate distributions are considered for selected values of the overall response probability and a range of alternatives. For the Cox regression model we consider both constant and non-constant hazard rates. The results show that in general the approach is remarkably accurate even in relatively small samples. Some discrepancies are, however, found in small samples with few events and a highly skewed covariate distribution. Comparison with results based on alternative methods for logistic regression models with a single continuous covariate indicates that the proposed method is at least as good as its competitors. The method is easy to implement and therefore provides a simple way to extend the range of problems that can be covered by the usual formulas for power and sample size determination.

Breast Neoplasms↗

PubMed2006

Polymorphisms of phase II xenobiotic-metabolizing and DNA repair genes and in vitro N-ethyl-N-nitrosourea-induced O6-ethylguanine levels in human lymphocytes.

This study tested the hypothesis that genetic variants of phase II detoxification enzymes and DNA repair proteins affect individual response to DNA damage from alkylating agents. In 171 healthy individuals, an immunoslot blot assay was used to measure O6-ethylguanosine (O6-EtGua) adduct levels in peripheral blood lymphocytes treated with N-ethyl-N-nitrosourea (ENU) in vitro. The genotypes of GSTM1, GSTT1, GSTP1 I(105)V and A(114)V, MGMT L(84)F and I(143)V, XPD D(312)N and K(751)Q, and XRCC3 T(241)M were determined. Demographic and exposure information was collected by in-person interview. Student's t-test, analysis of (co)variance, and multiple linear regression models were used in statistical analyses. The mean and median (range) O6-EtGua levels were 94.6 and 84.8 (3.2-508.1)fmol/g DNA, respectively. The adduct level was significantly lower in people who smoked >or=25 years than that in never-smokers (square-root transformed mean values 8.20 versus 9.37, P=0.03). Multiple linear regression models revealed that GSTT1 (beta=-2.36, P=0.009) polymorphism was a significant predictor of the level of adducts in 82 never-smokers, whereas the number of years smoked (beta=-0.08, P=0.005) and XRCC3 T(241)M (beta=2.22, P=0.007) in 89 ever-smokers. The association between GSTP1 I(105)V, MGMT I(143)V, and XPD D(312)N with the level of adducts was not conclusive. Each polymorphism could explain 2-10% of the variation of the adduct level. These observations suggest that GSTT1 null and XRCC3 T(241)M polymorphism may have some functional significance in modulating the level of ENU-induced DNA damage and these effects are smoking-dependent. Results from this exploratory study need to be confirmed in other experimental systems.

Aged↗

PubMedDate not supplied

Prospective comparison of retrograde and antegrade femoral intramedullary nailing.

OBJECTIVE: To prospectively compare the results, function, and complications of antegrade and retrograde femoral nailing for femoral shaft fractures. DESIGN: Prospective, randomized. SETTING: Urban Level 1 trauma center. PATIENTS: One hundred consecutive femoral shaft fractures. Fifty-four nails inserted retrograde and forty-six inserted antegrade. INTERVENTION: Ten-millimeter antegrade or retrograde nail inserted for a femoral shaft fracture after reaming. OUTCOME MEASUREMENTS: A comparison of the outcomes after antegrade and retrograde nailing of the femur. Data were collected for analysis on comminution, set-up and starting point times, open grade, location of fracture, injury severity score, body mass index, time to union, knee pain and motion, hip and thigh pain, and nail to intramedullary canal diameter difference. A linear regression model was employed. RESULTS: Knee motion was 120 degrees in all but one knee in each group. The antegrade nailed femurs healed faster than those treated retrograde (A = 14.4, R = 18.1 weeks, p = 0.0496). More patients required dynamization for union in the retrograde insertion group (17 percent versus 5 percent, p = 0.10, NS). In a linear regression model, a nail-to-canal-diameter difference and retrograde nailing had an association with an increased time to union. Knee pain was equal in both groups; however, thigh pain was higher in the antegrade group (p = 0.0108). All of the antegrade nailed femurs healed (100 percent), and 98 percent (one nonunion) of the retrograde femurs healed after secondary procedures. CONCLUSIONS: Both antegrade and retrograde nailing yielded high union rates. Each insertion technique has its own advantages and disadvantages. The two insertion modes appear to be relatively equal for the treatment of femoral shaft fractures.

Adult↗

PubMed2001

Environmental tobacco smoke and lung function in employees who never smoked: the Scottish MONICA study.

OBJECTIVES: To investigate the relation between lung function in employees and exposure to environmental tobacco smoke (ETS) at work and elsewhere. METHODS: Never smokers in employment (301) were identified from the fourth Scottish MONICA survey. They completed a self administered health record, which included details of exposure to ETS, and attended a survey clinic for physical and lung function measurements, and for venepuncture for estimation of serum cotinine. Differences in lung function in groups exposed to ETS were tested by analysis of variance (ANOVA), the exposure-response relation by a linear regression model, and a case-control analysis undertaken with a logistic regression model. RESULTS: Both men and women showed effects on forced expiratory volume in the first second (FEV(1)) and forced vital capacity (FVC) from exposure to ETS-higher exposure going with poorer lung function. This was found at work, and in total exposure estimated from ETS at work, at home, and at other places. Linear regression showed an exposure-response relation, significant for ETS at work, total exposure, and exposure time/day, but not at home or elsewhere. Compared with those not exposed to ETS at work, those who were exposed a lot had a 254 ml (95% confidence interval (95% CI) 84 to 420) reduction in FEV(1), and a 273 ml (60 to 480) reduction in FVC after adjusting for confounders. Although lung function was not significantly associated with serum cotinine in all the data, a significant inverse relation between cotinine concentration and FVC occurred in men who had had blood collected in the morning. Case-control analysis also showed a significant exposure-response relation between ETS, mainly at work, and lung function. A higher exposure measured both by self report and serum cotinine went with lower lung function. CONCLUSION: The exposure-response relation shows a reduction in pulmonary function of workers associated with passive smoking, mainly at work. These findings endorse current policies of strictly limiting smoking in shared areas, particularly working environments.

Adult↗