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PubMed2003

Association of resistin gene 3'-untranslated region +62G-->A polymorphism with type 2 diabetes and hypertension in a Chinese population.

Resistin, a recently discovered polypeptide, antagonizes insulin action and may play a part in the pathogenesis of insulin resistance. This study investigates whether resistin gene polymorphism can be associated with type 2 diabetes. We studied 1102 Chinese type 2 diabetes patients and 743 subjects without diabetes. The resistin 3'-untranslated region (UTR) +62G-->A polymorphism was determined by PCR. Type 2 diabetes subjects had a lower frequency of resistin gene 3'UTR +62A allele (GG:GA/AA, 83.5%:16.5%) than the controls (GG:GA/AA, 75.1%:24.9%; odds ratio, 1.524; 95% confidence interval, 1.268-1.831; P < 0.001). Unexpectedly, diabetic patients with the GG genotype had a higher prevalence of hypertension (GG:GA/AA, 49.8%:36.2%; odds ratio, 1.375; 95% confidence interval, 1.116-1.693; P = 0.001). Logistic regression analysis confirmed that the resistin gene 3'UTR +62G-->A polymorphism acts as an independent contributing factor to type 2 diabetes and hypertension. The mean systolic and diastolic blood pressure levels in diabetic subjects with the GG genotype (144 +/- 21/87 +/- 13 mm Hg) were significantly higher than those in subjects with GA/AA variants (139 +/- 21/84 +/- 14 mm Hg; P = 0.004 and P = 0.002, respectively). Multiple linear regression analysis showed resistin gene polymorphism to be an independent factor associated with systolic and diastolic blood pressures in type 2 diabetes patients. These findings suggest that resistin may play a role in the pathogenesis of type 2 diabetes and insulin resistance-related hypertension.

3' Untranslated Regions↗

PubMed2004

Involvement of monkey inferior colliculus in spatial hearing.

The midbrain inferior colliculus (IC) is implicated in coding sound location, but evidence from behaving primates is scarce. Here we report single-unit responses to broadband sounds that were systematically varied within the two-dimensional (2D) frontal hemifield, as well as in sound level, while monkeys fixated a central visual target. Results show that IC neurons are broadly tuned to both sound-source azimuth and level in a way that can be approximated by multiplicative, planar modulation of the firing rate of the cell. In addition, a fraction of neurons also responded to elevation. This tuning, however, was more varied: some neurons were sensitive to a specific elevation; others responded to elevation in a monotonic way. Multiple-linear regression parameters varied from cell to cell, but the only topography encountered was a dorsoventral tonotopy. In a second experiment, we presented sounds from straight ahead while monkeys fixated visual targets at different positions. We found that auditory responses in a fraction of IC cells were weakly, but systematically, modulated by 2D eye position. This modulation was absent in the spontaneous firing rates, again suggesting a multiplicative interaction of acoustic and eye-position inputs. Tuning parameters to sound frequency, location, intensity, and eye position were uncorrelated. On the basis of simulations with a simple neural network model, we suggest that the population of IC cells could encode the head-centered 2D sound location and enable a direct transformation of this signal into the eye-centered topographic motor map of the superior colliculus. Both signals are required to generate rapid eye-head orienting movements toward sounds.

Acoustic Stimulation↗

PubMed2006

GNB3 C825T and ACE I/D polymorphisms on the sodium-proton exchanger and the prevalence of essential hypertension in males.

BACKGROUND: The aim of the study was to verify the hypothesis if the interaction between the G protein beta3 subunit (GNB3) C825T polymorphism and ACE I/D polymorphism could lead to the disclosure of increased activity of sodium-proton exchanger and hypertension. METHODS: The study included 44 male patients, median age: 40 years. Patients were divided into two groups: 26 patients with essential hypertension (EH), and 18 subjects in the normotensive group (C). RESULTS: CT + TT genotypes of GNB3 predominated in patients with hypertension (65%) compared to normotensive patients (12%) (p <0.01). No significant differences were observed in the frequency of ACE gene polymorphisms between the examined groups. Significantly higher activity of erythrocyte NHE in patients with EH was observed: median 8.83 (interquartile range 4.27) mmol/l RBC/h, compared to C: median 6.18 (2.80) mmol/l RBC/h, p <0.001. Multiple logistic regression analysis showed that the presence of the T allele increased the risk of hypertension 16-fold (p <0.01) and higher erythrocyte NHE activity 2-fold per each unit of activity (p <0.01). DD genotype of ACE polymorphism did not increase the risk of hypertension. No significant interaction of the influence of GNB3 T allele and ACE DD genotype on the risk of hypertension was observed. In multiple linear regression analysis, none of the examined genotypes and their interactions influenced NHE activity. CONCLUSIONS: The presence of the T allele of GNB3 polymorphism and increased activity of erythrocyte NHE independently of ACE genotype increase the risk of hypertension.

Adult↗

PubMed2000

Long-term changes in left ventricular hypertrophy after renal transplantation.

BACKGROUND: Concentric and eccentric left ventricular hypertrophy are common progressive disorders in dialysis patients and are associated with cardiac failure and death. Although partial regression of these abnormalities is known to occur during the first post-transplant year, their long-term evolution is unknown. METHODS: A total of 143 of 433 dialysis patients participating in a long-term prospective cohort study received renal transplants. Laboratory parameters were assessed monthly. Echocardiography was performed annually. Left ventricular mass index (LVMI) and cavity volume index were calculated according to standard formulae. Multiple linear regression was used to model change in LVMI as a function of baseline clinical and laboratory variables. RESULTS: LVMI fell from 161 g/m2 at 1 year to 146 g/m2 (P=0.009) g/m2 after 2 years. No further regression was seen in years 3 and 4. Left ventricular volume index showed similar trends, with a decline from year 1 to year 2 (P=0.05) followed by stabilization in years 3 and 4. Older age, long duration of hypertension, need for more than one antihypertensive, high pulse pressure in normal-size hearts, and low pulse pressure in dilated hearts were significantly associated with failure of regression of LVMI between the first and second years (MLR, P<0.000001, r2=0.57). CONCLUSIONS: Regression of left ventricular hypertrophy continues beyond the first year after renal transplantation, reaching a nadir at 2 years and persisting into the third and fourth posttransplant years. Failure to regress was associated with older age, hypertension, high pulse pressure in normal-size hearts and low pulse pressure in dilated hearts.

Adult↗

PubMedDate not supplied

Influence of variations in implant diameters: a 3- to 5-year retrospective clinical report.

Sixty-seven patients ranging in age from 16 to 86 years were included in this 3- to 5-year retrospective report focusing on implant survival and marginal bone remodeling in relation to implant diameter. A total of 299 Brånemark implants (3.75-mm diameter: 141; 4.0-mm diameter: 61; 5.0-mm diameter: 97) were placed in 16 completely and 51 partially edentulous arches. Seven of the 141 implants in the 3.75-mm-diameter group failed (5%). The corresponding value for the 4.0-mm-wide implants was 2 of 61 (3%). The highest failure rate, 18% (17/97), was seen for the 5.0-mm-diameter implants. The least favorable cumulative survival rates were seen in mandibles after 5 years and involving 4.0-mm- and 5.0-mm-diameter implants (84.8% and 73.0%, respectively). The marginal bone loss was generally low over the 5-year period. When the data were evaluated by the Cox regression analysis, a relationship was found between implant failure and implant diameter (P < .05), with a higher failure rate for the 5.0-mm-diameter implant. However, no relationship could be seen between implant failure and jaw type, or bone quality and quantity (P > .05). Neither was any relationship seen between marginal bone loss and bone quality and quantity, implant diameter, or jaw type when tested by multiple linear regression analysis (P > .05). A learning curve, poor bone quality, and changed implant design were suggested as possible reasons for the less positive outcome seen for the 5.0-mm-diameter implant. The fact that this implant was often used as a rescue implant when the standard ones were not considered suitable or did not reach initial stability was another plausible explanation.

Adolescent↗

PubMed1997

Advances in statistical methods to map quantitative trait loci in outbred populations.

Statistical methods to map quantitative trait loci (QTL) in outbred populations are reviewed, extensions and applications to human and plant genetic data are indicated, and areas for further research are identified. Simple and computationally inexpensive methods include (multiple) linear regression of phenotype on marker genotypes and regression of squared phenotypic differences among relative pairs on estimated proportions of identity-by-descent at a locus. These methods are less suited for genetic parameter estimation in outbred populations but allow the determination of test statistic distributions via simulation or data permutation; however, further inferences including confidence intervals of QTL location require the use of Monte Carlo or bootstrap sampling techniques. A method which is intermediate in computational requirements is residual maximum likelihood (REML) with a covariance matrix of random QTL effects conditional on information from multiple linked markers. Testing for the number of QTLs on a chromosome is difficult in a classical framework. The computationally most demanding methods are maximum likelihood and Bayesian analysis, which take account of the distribution of multilocus marker-QTL genotypes on a pedigree and permit investigators to fit different models of variation at the QTL. The Bayesian analysis includes the number of QTLs on a chromosome as an unknown.

Bayes Theorem↗

PubMedDate not supplied

Epidemiology of enamel hypoplasia in deciduous teeth: explaining variation in prevalence in western India.

This study is based on seven samples of school children (n = 516) from rural (five groups) and urban (two groups) settings in western Maharashtra, India. Height and weight were recorded for each subject. Intra-oral observation of the labial surface of maxillary and mandibular anterior teeth was conducted with a low power (3x) illuminated hand lens. Presence of enamel hypoplasia was recorded on a dental chart by drawing the size and location of the defect on the affected tooth. Data analysis was conducted in two stages: 1) Enamel hypoplasia (EH) prevalence was analyzed by percentage of teeth and by percentage of individuals affected for the composite sample and independently for each study group and 2) an assessment of the relationship between anthropometric variables (height and weight), socio-economic status (SES), and localized hypoplasia of primary canines (LHPC; Skinner, 1986) was evaluated using multiple linear regression analysis. EH was observed less often in deciduous incisors (0.2% in di(2) to 2.5% in di(2)) than in deciduous canines (dc). Mandibular dc were affected with the greatest frequency (23.1%, tooth count). The overall individual count prevalence of dc hypoplasia (LHPC) is 26.2% (134/511) for all village samples and sexes combined. Difference in LHPC frequency by sex is non-significant, with males (24.7%, 70/284) and females (28.2%, 64/227) exhibiting nearly equal values. Significant inter-group variation in LHPC prevalence was documented among the seven groups, and the range of LHPC prevalence the among living groups exceeds variability in LHPC among four prehistoric Chalcolithic skeletal series of the Deccan Plateau. Multiple regression analysis revealed no significant relationship between height-for-age or weight-for-age in four school samples (two urban/two rural), but a significant association between stature and LHPC was found for three rural endogamous groups. Children with LHPC were significantly shorter by 1.5 cm than children who lacked the defect after controlling for differences in age. While the association between low birth weight and EH is strong and well documented clinically, the association between childhood stature and LHPC is more variable across groups and may reflect inter-group variation in the duration and intensity of environmental stress.

Age Factors↗

PubMed2006

Impact of liver steatosis on the antiviral response in the hepatitis C virus-associated chronic hepatitis.

BACKGROUND/AIM: Liver steatosis (LS) has been variably associated with chronic hepatitis C (CHC) but whether it affects sustained virological response to antiviral treatment and by what mechanisms is a question still under debate, at least for some genotypes. The aim of this work was to assess the frequency of LS, its relationship with host and viral factors and to what extent it can influence the response to antiviral combination therapy with pegylated interferon (INF)+ribavirin in a group of patients with CHC from a single center. PATIENTS: One hundred and twelve patients with histologically proven CHC were treated with Peg INF-alpha 2a 180 microg a week subcutaneously for 48 weeks plus ribavirin 1000 or 1200 mg/day, according to the patient's body weight. Steatosis was graded according to Brunt et al. RESULTS: Forty-six out of 112 patients (41.1%) were sustained virological responders (SVR). Seventy-two out of 112 (64.3%) presented with LS at histology; in this group, there were 24 patients (33.3%) with SVR compared with 22 (55%) of the non-steatosis group (chi(2)=6.5, P<0.02). Variables associated with the steatosis group were: higher serum levels of AST (P<0.04), alanine aminotransferase (P<0.02), gamma-GT (P<0.004), genotype 3a (P<0.03) and severity of histology (staging P<0.05) but at multiple linear regression analysis only genotype 3a and staging were significantly associated with LS. In the SVR group, age and body mass index (BMI) were significantly lower (P<0001 and P<0.03, respectively) compared with non-responders; moreover, genotype 1 was more frequent in the NR group, while genotype 3 was more frequent in the SVR group. At histology, grading and staging were also lower in the SVR group. Multiple logistic regression showed that only the grade of steatosis and genotype 3a were the variables independently associated with SVR. CONCLUSIONS: This study showed a frequency of LS on the higher side of the range so far reported in the literature and confirmed that it negatively influences response to therapy. Genotype1 was confirmed to be the most frequent type in our area. It is more frequent in patients with mild-moderate steatosis and seems to condition therapeutic response negatively, together with BMI and age. In contrast, genotype 3a is more frequent in patients with severe steatosis, but is a favorable predictor of successful therapy.

Adult↗

PubMed1997

Directional control of planar human arm movement.

We examined the patterns of joint kinematics and torques in two kinds of sagittal plane reaching movements. One consisted of movements from a fixed initial position with the arm partially outstretched, to different targets, equidistant from the initial position and located according to the hours of a clock. The other series added movements from different initial positions and directions and >40-80 cm distances. Dynamic muscle torque was calculated by inverse dynamic equations with the gravitational components removed. In making movements in almost every direction, the dynamic components of the muscle torques at both the elbow and shoulder were related almost linearly to each other. Both were similarly shaped, biphasic, almost synchronous and symmetrical pulses. These findings are consistent with our previously reported observations, which we termed a linear synergy. The relative scaling of the two joint torques changes continuously and regularly with movement direction. This was confirmed by calculating a vector defined by the dynamic components of the shoulder and elbow torques. The vector rotates smoothly about an ellipse in intrinsic, joint torque space as the direction of hand motion rotates about a circle in extrinsic Cartesian space. This confirms a second implication of linear synergy that the scaling constant between the linearly related joint torques is directionally dependent. Multiple linear regression showed that the torque at each joint scales as a simple linear function of the angular displacement at both joints, in spite of the complex nonlinear dynamics of multijoint movement. The coefficients of this function are independent of the initial arm position and movement distance and are the same for all subjects. This is an unanticipated finding. We discuss these observations in terms of the hypothesis that voluntary, multiple degrees of freedom, rapid reaching movements may use rule-based, feed-forward control of dynamic joint torque. Rule-based control of joint torque with separate dynamic and static controllers is an alternative to models such as those based on the equilibrium point hypotheses that rely on a positionally based controller to produce both dynamic and static torque components. It is also an alternative to feed-forward models that directly solve the problems of inverse dynamics. Our experimental findings are not necessarily incompatible with any of the alternative models, but they describe new, additional findings for which we need to account. The rules are chosen by the nervous system according to features of the kinematic task to couple muscle contraction at the shoulder and elbow in a linear synergy. Speed and load control preserves the relative magnitudes of the dynamic torques while directional control is accomplished by modulating them in a differential manner. This control system operates in parallel with a positional control system that solves the problems of postural stability.

Arm↗

PubMed1990

Serum baseline hyaluronate and disease activity in rheumatoid arthritis.

The baseline serum hyaluronate (HA) concentration from samples obtained five to seven hours after mobilization of the patient was quantified using a radiometric 125I-HA binding method in 58 patients with rheumatoid arthritis and compared with several clinical and laboratory parameters by means of stepwise multiple linear regression. In the age- and sex-adjusted model, the variables with independent predictive value for serum hyaluronate concentration were the erythrocyte sedimentation rate (ESR) and the joint score index measuring the extent of the synovial inflammation. The estimated synovial mass index and C-reactive protein values did not improve the fit of the model after ESR and joint score were entered, and were left out from the multiple regression equation. When ESR and joint score were studied in univariate regression analysis with serum hyaluronate, the coefficients were r = 0.492 and r = 0.397, and the P values were P less than 0.001 and P less than 0.005, respectively. It was concluded that the baseline hyaluronate level in serum is closely related to the synovitic activity of the rheumatoid inflammation and that measurement of serum hyaluronate is of value when the activity and extent of synovial inflammation is being assessed in patients with rheumatoid arthritis.

Adult↗

PubMedDate not supplied

Correlation between rheologic properties and in vitro ciliary transport of rat nasal mucus.

The relationship between mucus rheologic variables and in vitro ciliary transport was investigated in mucus samples collected from the upper airways of 30 Wistar rats. In vitro mucus transportability was determined by means of the frog palate preparation. Rheologic evaluation was done by measuring the rigidity modulus (log G*, representing the vectorial sum of viscosity and elasticity) and the loss tangent (tan delta, i.e. the ratio between viscosity and elasticity) at 1 and 100 radian/s using a magnetic microrheometer. The correlation between the rheologic variables and in vitro mucus transportability was made by stepwise multiple linear regression analysis, with frog palate transport rate considered as the dependent variable. A significant relationship was obtained between the rheologic parameters (log G* and tan delta) measured at 1 radian/s and the frog palate transport ratio. The relative speed of mucus samples was related to rheology according to the following relationship: rat/frog speed ratio = 1.666-0.434 log G*-0.331 tan delta, for G* and delta determined at 1 radian/s (multiple r = 0.666, p < 0.001). Transport rates predicted from the above formula gave a satisfactory fit to those observed in a second set of 30 rats. The present results indicate that the overall mucus impedance, as well as the ratio between viscosity and elasticity, are important in determining the efficiency of clearance. In addition, it was shown that measurements performed by applying relatively low frequency deformations are preferable for predicting ciliary transport.

Animals↗

PubMed2006

Association between dietary glycemic index, glycemic load, and body mass index in the Inter99 study: is underreporting a problem?

BACKGROUND: The few studies examining the potential associations between glycemic index (GI), glycemic load (GL), and body mass index (BMI) have provided no clear pictures. Underreporting of energy intake may be one explanation for this. OBJECTIVE: We examined the associations between GI, GL, and BMI by focusing on the confounding factor of total energy intake and the effect of exclusion of low energy reporters (LERs). DESIGN: This was a cross-sectional study of 6334 subjects aged 30-60 y. Dietary intake was estimated from a food-frequency questionnaire. GI and GL were estimated by using white bread as the reference food. Underreporting of energy intake was assessed as reported energy intake divided by basal metabolic rate (EI/BMR); LERs were defined as those having an EI/BMR < 1.14. Univariate and multiple linear regression models were used to test for associations between GI, GL, and BMI. The confounders were sex, age, smoking, physical activity, alcohol intake, and energy intake. All analyses were conducted on 1) the entire population and 2) a subsample excluding LERs. RESULTS: In the univariate analyses of the entire population, GL was inversely associated with BMI. No association was observed for GI. After full adjustment (including energy intake), both GI and GL were positively associated with BMI. When LERs were excluded, GL was positively associated with BMI in all analyses, and GI was positively associated with BMI in the multiple analyses. CONCLUSIONS: We showed a positive association between GI, GL, and BMI. Energy adjustment and the exclusion of LERs significantly affected the results of the analysis; thus, we stress the importance of energy adjustment.

Adult↗

PubMed1990

Estimation of left ventricular ejection fraction with healed myocardial infarction by multiple regression analysis of electrocardiographic Minnesota Q-QS codes. POSCH Group.

The cardiac damage caused by a myocardial infarction may be evidenced by abnormal electrocardiographic Q-QS complexes (i.e., Minnesota Q-QS codes) and by impairment of left ventricular function. It has been shown that the level of significance of the Q-QS codes is highly correlated with the extent of left ventricular impairment. This study was directed to quantitating this relationship in subjects with a healed myocardial infarction and expressing it mathematically. Using multiple linear regression analysis, a coefficient value was obtained corresponding to the level of significance of each Q-QS code located in each electrocardiographic cardiac area. The left ventricular ejection fraction was estimated by subtracting the coefficient of the most significant code present in each cardiac area from the constant, which was calculated to be the ejection fraction in the absence of any Q-QS code. The results were reproducible, and there was a good correlation between the estimated and measured ejection fraction.

Adult↗

PubMed2004

A multicountry ecologic study of risk and risk reduction factors for prostate cancer mortality.

OBJECTIVE: The objective of this research is to identify and determine the relative importance of dietary and environmental risk and risk reduction factors for prostate cancer mortality. MATERIALS AND METHODS: A multicountry ecologic approach was used in multivariate regression analyses with prostate cancer mortality rates and dietary factors and solar ultraviolet-B (UV-B) radiation. Prostate cancer mortality rates for 32 predominantly Caucasian countries for the late 1990s were obtained from the World Health Organization. Dietary supply data were obtained from the Food and Agriculture Organization. Annual solar UV-B dose data were obtained from European ground stations and used to estimate values elsewhere. Linear and multiple linear regression analyses were conducted for all 32 countries as well as the 20 European countries. RESULTS: The strongest risk factor for prostate cancer mortality was animal products, with the nonfat portion of milk and alcohol being somewhat weaker; the strongest risk reduction factors were onions, other protective vegetable products (excluding alcohol, oils, and sweeteners), and solar UV-B radiation. Dietary data for 1979-81 yielded the highest correlations. CONCLUSIONS: These results are consistent with insulin-like growth factor-I (IGF-I), being an important risk factor for prostate cancer, with alcohol and calcium being less important risk factors, and with allium family vegetables, and, to a lesser extent, vitamin D being important risk reduction factors. These results should provide guidance for additional studies on dietary and environmental links to prostate cancer.

Alcohol Drinking↗

PubMed2002

Pulse wave velocity and the second derivative of the finger photoplethysmogram in treated hypertensive patients: their relationship and associating factors.

OBJECTIVES: To clarify the factors influencing two measures of arterial stiffness, pulse wave velocity (PWV) and the second derivative of the finger photoplethysmogram (SDPTG), and to evaluate their relationship in treated hypertensive subjects. SUBJECTS AND METHODS: The subjects were 294 hypertensive patients aged 32-91 years (mean, 61.4 +/- 10.5 years). After blood pressure (BP) was measured, carotid-femoral PWV and SDPTG were recorded with the subjects in the supine position, with the aid of an automatic device. For assessing SDPTG, we focused mainly on the ratios of the absolute value of the height of the early negative 'b' wave (B) and that of the late re-decreasing 'd' wave (D) to that of the initial positive 'a' wave (A), namely the B : A and D : A ratios, and the aging index (AGI). Factors influencing PWV and SDPTG indices, and the relationship between PWV and SDPTG indices were evaluated by bivariate and multivariate analyses. RESULTS: According to multiple linear regression analysis, age, systolic blood pressure (SBP), and heart rate (HR) were variables independently and positively correlated with PWV. The age and BP were significantly and independently related to SDPTG indices; there were positive correlations with the D : A ratio and AGI, and negative correlations with the B : A ratio. HR was correlated negatively with the D : A ratio and AGI, and positively with the B : A ratio. According to multiple logistic regression analysis, adjusted-odds ratios of high PWV, low B : A ratio, high D : A ratio, and high AGI were significantly elevated among the elderly and among the subjects with uncontrolled BP. Although PWV and the SDPTG indices were associated with common factors, including age and BP, bivariate analysis revealed that they were only weakly correlated with each other. CONCLUSIONS: The results suggest that in hypertensive patients, PWV and SDPTG provide different information about arterial properties at central and peripheral sites.

Aged↗

PubMedDate not supplied

The inverse association between age and cholesterol level among older patients: the role of poor health status.

BACKGROUND: The total cholesterol concentration decreases with age in older people. The reasons for this phenomenon are controversial. This study investigated the hypothesis that poor health status is a determinant of the inverse association between age and cholesterol in older persons. METHODS: Cross-sectional study of 2,486 (53% women) older medical patients (> or =65 years) admitted at 35 centers of the Gruppo Italiano di Farmacovigilanza nell'Anziano (GIFA) study in Italy. Total cholesterol was measured on the first day after admission to the hospital. Disease burden and comorbidity were assessed by the Charlson index; low serum albumin and iron were considered markers of frailty and poor health. RESULTS: In men there was a significant, inverse age-cholesterol relationship (-0.97 mg/dl per year, p<0.001). In women the association was nonlinear and cholesterol significantly decreased after the age of 75 (-0.95 mg/dl per year, p<0.005). In multiple linear regression analysis, indicators of poor health accounted for almost two thirds of the crude effect of age on the cholesterol level in both men and women (adjusted coefficients for age were: for men, -0.38 mg/dl per year, p = 0.044; for women after the age of 75, -0.37 mg/dl per year, p = 0.205). The unadjusted probability of having low cholesterol significantly increased with age among men (p for trend <0.005). In multiple logistic regression, indicators of poor health were strongly associated with low cholesterol in both men and women. After adjusting for indicators of poor health, the association between age and low cholesterol in men was no longer present. CONCLUSION: These findings suggest that the age-dependent reduction of cholesterol often observed in clinical and epidemiologic studies is substantially explained by the effect of poor health status. Low cholesterol in older persons may be a marker of poor health.

Age Factors↗

PubMed1991

Introduction of bias in residency-candidate interviews.

We have developed, as part of our resident applicant ranking process, a computerized weighted scoring system incorporating, among other variables, the interview score (IS). This study was undertaken to test the IS as a dependent variable when the applicant file is available during the interview. Over a 3-year period, each of two faculty members interviewed 133 candidates in a "blinded" fashion (file unavailable) or 290 candidates with an "open" file. The mean discrepancy between paired interviewers (1 to 10 scale) was 1.34 +/- 0.10 for the blinded group versus 0.93 +/- 0.06 for the open group (p less than 0.001). Individual and multiple regression analysis were used to test the IS as a dependent variable in the open group, with the blinded group as a control. In each instance (except clerkship grades), the IS correlated more closely with other parameters (p less than 0.05) in the open group. Correlation coefficients were 0.27 (blinded) and 0.64 (open) for weighted scores combining all parameters (p less than 0.001) and 0.39 (blinded) and 0.65 (open) for multiple linear regression analysis (p less than 0.001). We conclude that the IS is significantly influenced if other objective variables are at hand, thus deflating the actual weight of the interview. To accurately quantify the value of the interview, a correction factor must be applied, or, more appropriately, the interview must be conducted blindly.

Academic Medical Centers↗

PubMed2004

Outcome of pregnancy in homozygous sickle cell disease.

OBJECTIVE: Previous reports on pregnancy in homozygous sickle cell (SS) disease are biased by hospital-based, more severely affected subjects and may have underestimated recurrent early pregnancy losses. We report pregnancy outcome in a representative sample of SS subjects subsequently referred to as "subjects" or "sickle cell subjects," and matched normal controls followed from birth. METHODS: The outcomes of 94 pregnancies in 52 subjects and 157 pregnancies in 68 controls followed in a cohort study from birth are presented. Outcome measures included the age at menarche, interval to first pregnancy, outcome of pregnancy, and maternal complications. Possible predictors of low birth weight are assessed. Outcomes were compared by the Kaplan-Meier analysis for interval to first pregnancy and by Student t test, chi(2) test, or Fisher exact test, as appropriate. Correction was made for multiple testing, and multiple linear regression was used for analysis of birth weight. RESULTS: Compared with controls, SS subjects had later menarche (median age 15.4 versus 13.0 years) and first pregnancy (median age 23.7 versus 20.1 years), and more spontaneous abortions (36% versus 10%). Babies of SS subjects had a lower gestational age (P <.001) and lower birth weight (P <.001), the latter being significantly affected by sickle-related events in pregnancy. There was no difference in pregnancy-induced hypertension, preeclampsia, or antepartum or postpartum hemorrhage, but a retained placenta was marginally more common in SS subjects (Fisher exact test, P =.007 after adjustment for multiple testing). Two SS subjects died, a mortality rate of 2.1%. CONCLUSION: The increased fetal loss and maternal morbidity in mothers with homozygous sickle cell disease is confirmed. LEVEL OF EVIDENCE: II-2

Abortion, Spontaneous↗