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Baseline Variables (baseline + variable)
Selected AbstractsFive-Year Survival Distributions of Short-Length (10 mm or less) Machined-Surfaced and Osseotite® ImplantsCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2004Sylvan Feldman DDS ABSTRACT Background: In cases of reduced alveolar bone height, implants of short length (10 mm or less) may be employed although there is a perceived risk that because of their small stature they will be unable to tolerate occlusal loads and will fail to osseointegrate. Purpose: This report describes an analysis of prospective multicenter clinical studies evaluating the risk for failure of short-length implants, comparing dual acid-etched (DAE) Osseotite® implants (Implant Innovations, Inc., Palm Beach Gardens, FL, USA) to machined-surfaced implants. Materials and Methods: Admission criteria were the same for both data sets. Baseline variables of demographics including age, gender and smoking status, bone quality, location, implant dimensions, and types of prostheses were compared to ensure balance among groups. Cumulative survival rates (CSRs) were calculated with the Kaplan-Meier estimator. Results: The implant data included 2,294 implants for the DAE series and 2,597 implants for the machined-surfaced series. Patient demographics showed similar percentages of occurrence for all variables. The distributions of implants between short- and standard-length data sets for baseline variables including width, location, and restorative type were similar, qualifying these data sets for comparison of the independent variable of length. Overall, there was a 2.2% difference in 5-year CSRs between the machined-surfaced short- and the standard-length implants. For these implants a 7.1% difference was observed in the posterior maxilla and an 8.5% difference in the anterior maxilla. For DAE implants the overall difference between "standards" and "shorts" was 0.7%, which is not statistically significant. Conclusion: In this analysis the difference in CSRs between short- and standard-length implants was greater for machined-surfaced implants than for DAE implants. [source] What predicts the occurrence of the metabolic syndrome in a population-based cohort of adult healthy subjects?DIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 1 2009S. Bo Abstract Background Metabolic syndrome (MS), the concurrence of hyperglycaemia, dyslipidaemia, hypertension and visceral obesity, increases cardiovascular risk and mortality. Predictors of MS were previously evaluated in patients without the full syndrome, but with some of its traits. This might confound the resulting associations. Methods The relationship between baseline variables and MS development was evaluated in healthy middle-aged subjects without any MS component at baseline, over a 4.5-year follow-up. Results From a population-based cohort of 1658 subjects, 241 individuals showed no MS components and 201 (83.4%) of them participated in a follow-up screening. At baseline, patients who developed the MS (n = 28/201; 13.9%) showed significantly higher Homeostasis Model Assessment-Insulin Resistance score (HOMA-IR) and C-reactive protein (CRP) values, and lower exercise level than subjects who did not. In a multiple logistic regression analysis, after multiple adjustments, the only baseline variable significantly (p < 0.01) associated with the MS was CRP (OR = 4.05; 95% CI 2.23,7.38; p < 0.001). Results did not change after adjusting for weight gain. The area under the receiver-operating curve was 0.83 for CRP after multiple adjustments. The optimal cut-off point of baseline CRP values was 2.1 mg/L, with 86% (95% CI 81,90) sensitivity and 75% (69,81) specificity in predicting the MS. Baseline CRP resulted associated with after-study glucose values in a multiple regression model (, = 0.14; 0.08,0.20; p < 0.001). Conclusions Higher baseline CRP values confer a significant increased risk of developing the MS in healthy subjects, independently of weight gain. Copyright © 2009 John Wiley & Sons, Ltd. [source] The effect of diabetes on heart rate and other determinants of myocardial oxygen demand in acute coronary syndromesDIABETIC MEDICINE, Issue 9 2004K. Foo Abstract Aims To compare major determinants of myocardial oxygen demand (heart rate, blood pressure and rate pressure product) in patients with and without diabetes admitted with acute coronary syndromes. Methods A cross-sectional study of the relation between diabetes and haemodynamic indices of myocardial oxygen demand in 2542 patients with acute coronary syndromes, of whom 1041 (41.0%) had acute myocardial infarction and 1501 (59.0%) unstable angina. Results Of the 2542 patients, 701 (27.6%) had diabetes. Major haemodynamic determinants of myocardial oxygen demand were higher in patients with than without diabetes: heart rate 80.0 ± 20.4 vs. 75.2 ± 19.2 beats/minute (P < 0.0001); systolic blood pressure 147.3 ± 30.3 vs. 143.2 ± 28.5 mmHg (P = 0.002); rate-pressure product 11533 ± 4198 vs. 10541 ± 3689 beats/minute × mmHg (P < 0.0001). Multiple regression analysis confirmed diabetes as a significant determinant of presenting heart rate [multiplicative coefficient (MC) 1.05; 95% confidence interval (CI) 1.03,1.07; P < 0.0001], rate pressure product (MC 1.09; CI 1.05,1.12; P < 0.0001) and systolic blood pressure, which was estimated to be 3.9 mmHg higher than in patients without diabetes (P = 0.003). These effects of diabetes were independent of a range of baseline variables including acute left ventricular failure and mode of presentation (unstable angina or myocardial infarction). Conclusions In acute coronary syndromes, heart rarte and other determinants of myocardial oxygen demand are higher in patients with than without diabetes, providing a potential contributory mechanism of exaggerated regional ischaemia in this high-risk group. [source] Identifying interacting predictors of falling among hospitalized elderly in Japan: A signal detection approachGERIATRICS & GERONTOLOGY INTERNATIONAL, Issue 2 2007Atsuko Nabeshima Falling is a complex phenomenon that involves interaction of multiple risk factors. The authors analyzed factors related to falls in a geriatric hospital to elucidate interaction of multiple risk factors for falls in elderly inpatients. Subjects were 364 patients (mean age, 81.7; women 76.7%) who were aged 60 years and over and had been hospitalized for more than 6 months between April 2000 and March 2001. A signal detection model was used to identify baseline variables that best divided the sample into subgroups using incidence of falling as an outcome variable. During a follow-up period, 91 patients (25%) had at least one incident of fall. Out of 14 independent variables, a higher-order interaction consisting of six significant variables was identified. Consequently, the subjects were categorized into seven subgroups whose fall rate varied 5.7,80.9%. We found that the combination of non-bedridden state, dementia, and medication of tranquilizers or sleeping drugs was the highest fall rate (80.9%). Signal detection analysis is useful to identify the combination of multiple risk factors of falling, and applicable to develop prevention programs for each subgroups. [source] Relationship between dental care and oral health in institutionalized elderly people in JapanJOURNAL OF ORAL REHABILITATION, Issue 9 2004Y. Shimazaki summary, This study examined the relationship between dental care and dental health status in institutionalized elderly people in Japan through a 6-year prospective cohort study. All the 719 subjects received both baseline and follow-up surveys. The uptake of dental care was examined at the follow-up survey. We examined the relationship between baseline variables and the provision of dental care, and the relationship between dental care and change of oral health status. About 47% of the subjects and about 60% of the baseline dentate subjects received some dental treatment during the 6-year follow-up period. The subjects who were in better systemic and dental health at baseline used dental services frequently. The number of teeth needing extraction decreased in the subjects who received dental treatment, and increased in the untreated subjects. Denture status was better in the treated subjects than in the untreated subjects. Dental care appears to be an important factor in maintaining a healthy oral status for the institutionalized elderly. [source] Effect of Pimobendan or Benazepril Hydrochloride on Survival Times in Dogs with Congestive Heart Failure Caused by Naturally Occurring Myxomatous Mitral Valve Disease: The QUEST StudyJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 5 2008J. Häggström Background: Myxomatous mitral valve disease (MMVD) continues to be an important cause of morbidity and mortality in geriatric dogs despite conventional therapy. Hypothesis: Pimobendan in addition to conventional therapy will extend time to sudden cardiac death, euthanasia for cardiac reasons, or treatment failure when compared with conventional therapy plus benazepril in dogs with congestive heart failure (CHF) attributable to MMVD. Animals: Two hundred and sixty client-owned dogs in CHF caused by MMVD were recruited from 28 centers in Europe, Canada, and Australia. Methods: A prospective single-blinded study with dogs randomized to PO receive pimobendan (0.4,0.6 mg/kg/d) or benazepril hydrochloride (0.25,1.0 mg/kg/d). The primary endpoint was a composite of cardiac death, euthanized for heart failure, or treatment failure. Results: Eight dogs were excluded from analysis. One hundred and twenty-four dogs were randomized to pimobendan and 128 to benazepril. One hundred and ninety dogs reached the primary endpoint; the median time was 188 days (267 days for pimobendan, 140 days for benazepril hazard ratio = 0.688, 95% confidence limits [CL] = 0.516,0.916, P= .0099). The benefit of pimobendan persisted after adjusting for all baseline variables. A longer time to reach the endpoint was also associated with being a Cavalier King Charles Spaniel, requiring a lower furosemide dose, and having a higher creatinine concentration. Increases in several indicators of cardiac enlargement (left atrial to aortic root ratio, vertebral heart scale, and percentage increase in left ventricular internal diameter in systole) were associated with a shorter time to endpoint, as was a worse tolerance for exercise. Conclusions and Clinical Importance: Pimobendan plus conventional therapy prolongs time to sudden death, euthanasia for cardiac reasons, or treatment failure in dogs with CHF caused by MMVD compared with benazepril plus conventional therapy. [source] Evaluation of gender differences in caregiver burden in home care: Nagoya Longitudinal Study of the Frail Elderly (NLS-FE)PSYCHOGERIATRICS, Issue 3 2006Yoshihisa HIRAKAWA Abstract Background:, Japan is presently experiencing a growth in the number of male caregivers and this situation has given rise to some concerns over gender differences. Previous studies have suggested that there are gender differences in caregiver burden in home care, however, it is still unclear whether or not gender differences exist. We therefore conducted this study to attain a better understanding of the Japanese male caregiver burden in home care, using data from the Nagoya Longitudinal Study of Frail Elderly (NLS-FE). Methods:, NLS-FE is a large prospective study of community-dwelling elderly persons eligible for public long-term care insurance who live in Nagoya city and use the services of the Nagoya City Health Care Service Foundation for Older People, which comprises 17 visiting nursing stations and corresponding care-managing centers, from November to December 2003. Data used in this study included the Japanese version of the Zarit Caregiver Burden Interview, caregivers' and dependents' characteristics, and the caregiving situation. The differences in dependent and caregiver characteristics between male and female caregiver groups were assessed using the ,2 -test for categorical variables or the unpaired t -test for continuous variables. Multiple logistic regression was used to examine the association between dependent and caregiver characteristics and caregiver burden. Results:, A total of 399 male caregivers and 1193 female caregivers were included in our analysis. Before and after controlling baseline variables, we did not detect a difference between male and female caregivers with respect to caregiver burden. Conclusion:, Our study suggests that differences in caregiver burden may not necessarily exist between male and female caregivers in Japan. [source] Some Methods of Propensity-Score Matching had Superior Performance to Others: Results of an Empirical Investigation and Monte Carlo simulationsBIOMETRICAL JOURNAL, Issue 1 2009Peter C. Austin Abstract Propensity-score matching is increasingly being used to reduce the impact of treatment-selection bias when estimating causal treatment effects using observational data. Several propensity-score matching methods are currently employed in the medical literature: matching on the logit of the propensity score using calipers of width either 0.2 or 0.6 of the standard deviation of the logit of the propensity score; matching on the propensity score using calipers of 0.005, 0.01, 0.02, 0.03, and 0.1; and 5 , 1 digit matching on the propensity score. We conducted empirical investigations and Monte Carlo simulations to investigate the relative performance of these competing methods. Using a large sample of patients hospitalized with a heart attack and with exposure being receipt of a statin prescription at hospital discharge, we found that the 8 different methods produced propensity-score matched samples in which qualitatively equivalent balance in measured baseline variables was achieved between treated and untreated subjects. Seven of the 8 propensity-score matched samples resulted in qualitatively similar estimates of the reduction in mortality due to statin exposure. 5 , 1 digit matching resulted in a qualitatively different estimate of relative risk reduction compared to the other 7 methods. Using Monte Carlo simulations, we found that matching using calipers of width of 0.2 of the standard deviation of the logit of the propensity score and the use of calipers of width 0.02 and 0.03 tended to have superior performance for estimating treatment effects (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Using Regression Models to Analyze Randomized Trials: Asymptotically Valid Hypothesis Tests Despite Incorrectly Specified ModelsBIOMETRICS, Issue 3 2009Michael Rosenblum Summary Regression models are often used to test for cause-effect relationships from data collected in randomized trials or experiments. This practice has deservedly come under heavy scrutiny, because commonly used models such as linear and logistic regression will often not capture the actual relationships between variables, and incorrectly specified models potentially lead to incorrect conclusions. In this article, we focus on hypothesis tests of whether the treatment given in a randomized trial has any effect on the mean of the primary outcome, within strata of baseline variables such as age, sex, and health status. Our primary concern is ensuring that such hypothesis tests have correct type I error for large samples. Our main result is that for a surprisingly large class of commonly used regression models, standard regression-based hypothesis tests (but using robust variance estimators) are guaranteed to have correct type I error for large samples, even when the models are incorrectly specified. To the best of our knowledge, this robustness of such model-based hypothesis tests to incorrectly specified models was previously unknown for Poisson regression models and for other commonly used models we consider. Our results have practical implications for understanding the reliability of commonly used, model-based tests for analyzing randomized trials. [source] Randomized, placebo-controlled trial of flax oil in pediatric bipolar disorderBIPOLAR DISORDERS, Issue 2 2010Barbara L Gracious Gracious BL, Chirieac MC, Costescu S, Finucane TL, Youngstrom EA, Hibbeln JR. Randomized, placebo-controlled trial of flax oil in pediatric bipolar disorder. Bipolar Disord 2010: 12: 142,154. © 2010 The Authors. Journal compilation © 2010 John Wiley & Sons A/S. Objectives:, This clinical trial evaluated whether supplementation with flax oil, containing the omega-3 fatty acid ,-linolenic acid (,-LNA), safely reduced symptom severity in youth with bipolar disorder. Methods:, Children and adolescents aged 6,17 years with symptomatic bipolar I or bipolar II disorder (n = 51), manic, hypomanic, mixed, or depressed, were randomized to either flax oil capsules containing 550 mg ,-LNA per 1 gram or an olive oil placebo adjunctively or as monotherapy. Doses were titrated to 12 capsules per day as tolerated over 16 weeks. Primary outcomes included changes in the Young Mania Rating Scale, Child Depression Rating Scale-Revised, and Clinical Global Impressions-Bipolar ratings using Kaplan-Meier survival analyses. Results:, There were no significant differences in primary outcome measures when compared by treatment assignment. However, clinician-rated Global Symptom Severity was negatively correlated with final serum omega-3 fatty acid compositions: %,-LNA (r = ,0.45, p < 0.007), % eicosapentaenoic acid (EPA) (r = ,0.47, p < 0.005); and positively correlated with final arachidonic acid (AA) (r = 0.36, p < 0.05) and docosapentaenoic acid (DPA) n-6 (r = 0.48, p < 0.004). The mean duration of treatment for ,-LNA was 11.8 weeks versus 8 weeks for placebo; however, the longer treatment duration for ,-LNA was not significant after controlling for baseline variables. Subjects discontinued the study for continued depressive symptoms. Conclusions:, Studies of essential fatty acid supplementation are feasible and well tolerated in the pediatric population. Although flax oil may decrease severity of illness in children and adolescents with bipolar disorder who have meaningful increases in serum EPA percent levels and/or decreased AA and DPA n-6 levels, individual variations in conversion of ,-LNA to EPA and docosahexaenoic acid as well as dosing burden favor the use of fish oil both for clinical trials and clinical practice. Additionally, future research should focus on adherence and analysis of outcome based on changes in essential fatty acid tissue compositions, as opposed to group randomization alone. [source] Alfuzosin 10 mg once daily for treating benign prostatic hyperplasia: a 3-year experience in real-life practiceBJU INTERNATIONAL, Issue 7 2008Guy Vallancien OBJECTIVES To assess the 3-year efficacy and safety of the selective ,1 -blocker alfuzosin at 10 mg once daily in men with lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH) in ,real-life practice'. The influence of treatment response on the risk of acute urinary retention (AUR) and BPH-related surgery was also analysed. PATIENTS AND METHODS In all, 689 European men (mean age 67.6 years) were enrolled by general practitioners in a 3-year open-label study with alfuzosin at 10 mg once daily. They were asked to complete the International Prostate Symptom Score (IPSS), its eighth question (bother score), and the Danish Prostatic Symptom Score for sexual function (DAN-PSSsex). Efficacy was analysed at the endpoint in the intent-to-treat population. The impact of baseline variables (age, PSA level, IPSS and bother severity) and dynamic variables (IPSS worsening of ,4 points and bother at the last available assessment under treatment) on the risk of AUR and BPH-related surgery was evaluated. RESULTS With alfuzosin, IPSS improved by 6.4 points (,33.4%) from baseline (P < 0.001), reaching ,3 points and >6 points in 71.3% and 47.2% of men, respectively. There were also significant (P < 0.001) improvements from baseline in nocturia (,0.8, ,25.5%), bother score (,1.7, ,40.7%) and DAN-PSSsex weighted scores with treatment. Symptom relief was rapid and maintained over 3 years. Overall, 78 men (12.4%) had an IPSS worsening of ,4 points, 16 (2.6%) had AUR, and 36 (5.7%) required BPH-related surgery. Symptom deterioration during treatment and high baseline PSA values were the best predictors of AUR and BPH-related surgery. Alfuzosin was well tolerated, dizziness being the most frequent adverse event (4.5%) possibly related to vasodilatation. Ejaculatory disorders were uncommon (0.4%). Changes in blood pressure remained marginal, including in men aged ,65 years and those receiving antihypertensive agents. CONCLUSION Alfuzosin administered for 3 years at 10 mg once daily in real-life practice is effective and well tolerated. High PSA values and symptom worsening under treatment appear the best predictors of AUR and BPH-related surgery in the long term. Treatment with alfuzosin might thus help to identify patients at risk of LUTS/BPH progression in order to optimize their management. [source] A pooled analysis of adjunctive topiramate in refractory partial epilepsyACTA NEUROLOGICA SCANDINAVICA, Issue 1 2003K. Peeters Objectives , To evaluate the impact of different dosages of topiramate (TPM) add-on to stable antiepileptic therapy for refractory partial epilepsy in adults. Material and methods , Pooled intention-to-treat analysis of six similarly designed double-blind, placebo-controlled trials, including 481 patients treated with doses of TPM 200, 400, 600 and 800 mg/day, and 265 patients receiving placebo. Results , Seizures were reduced by ,50% from baseline in 41% of TPM-treated patients and 15% of placebo-treated patients (P < 0.001); 5 and 0.8%, respectively, were seizure-free (P < 0.003). TPM was significantly better than placebo regardless of gender, age, baseline seizure rate as well as number and type of concomitant antiepileptic drugs. Efficacy was statistically significant in favour of TPM at all dose levels: at least 50% seizure reduction was achieved in 40% of patients with 200 mg, 41% with 400 mg, 44% with 600 mg and 41% with 800 mg TPM when compared with 15% with placebo (P , 0.001 for each dosage arm vs placebo). The median reduction in monthly seizure frequency was 38%, 42%, 45% and 38% vs 8%, respectively (P , 0.001). Moreover, response to TPM was significantly superior to placebo at each of the dose levels tested for most of the baseline variables. The total percentage of withdrawals increased with the dosage, and the withdrawals caused by adverse events increased from 3% with placebo to 7% with 200 mg TPM (not significant vs placebo), 15% with 400 mg TPM (P = 0.08), 16% with 600 mg TPM (P = 0.002) and 15% with 800 mg TPM (P = 0.003). Conclusion , The efficacy of TPM add-on in partial epilepsy is consistent across efficacy endpoints and independent of study population characteristics. The response at 200 mg TPM is similar to the response at higher doses, but as drop-outs caused by adverse events are more frequent above the 200 mg dose, this pooled analysis supports that 200 mg daily is a good target dose for add-on therapy in most patients with partial epilepsy, showing an excellent balance between efficacy and tolerability. [source] Outcomes with drug-eluting stents versus bare metal stents in acute ST-elevation myocardial infarction: Results from the Strategic Transcatheter Evaluation of New Therapies (STENT) Group,CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 7 2008Bruce R. Brodie MD Abstract Objectives: This study compares outcomes with drug-eluting stents (DES) versus bare metal stents (BMS) in patients with ST-elevation myocardial infarction (STEMI). Background: DESs have been effective in elective percutaneous coronary intervention (PCI), but their safety and efficacy in patients with STEMI have not been well studied. Methods: The STENT Registry is a multicenter United States registry evaluating outcomes of DES. Our study population includes patients with STEMI treated with either a DES or BMS who completed 9-month or 2-year follow-up. Outcomes were adjusted using propensity score analysis. Results: DES patients were younger, had less prior infarction and prior bypass surgery, but had smaller vessels and longer lesions. After adjusting for differences in baseline variables, there were no significant differences between DES and BMS in death, reinfarction, or major adverse cardiac events (MACE). DES had lower rates of stent thrombosis at 9 months (1.0% vs. 2.7%, HR 0.40 [0.17,0.95]) and lower rates of target vessel revascularization (TVR) at 9 months (4.0% vs. 7.5%, HR 0.55 [0.34,0.88]) and 2 years (8.0% vs. 11.3%, HR 0.57 [0.35,0.92]). There was a nonsignificant increase in stent thrombosis with DES versus BMS from 1 to 2 years (1.1% vs. 0.3%, P = 0.28). Conclusions: Our data suggest that DES used with primary PCI for STEMI are more effective than BMS in reducing TVR and are safe for up to 2 years. Whether DES are safe beyond 2 years and whether the reduction in TVR is enough to justify their use in STEMI will have to wait for the results of large randomized trials. 2008 Wiley-Liss, Inc. [source] Five-Year Survival Distributions of Short-Length (10 mm or less) Machined-Surfaced and Osseotite® ImplantsCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2004Sylvan Feldman DDS ABSTRACT Background: In cases of reduced alveolar bone height, implants of short length (10 mm or less) may be employed although there is a perceived risk that because of their small stature they will be unable to tolerate occlusal loads and will fail to osseointegrate. Purpose: This report describes an analysis of prospective multicenter clinical studies evaluating the risk for failure of short-length implants, comparing dual acid-etched (DAE) Osseotite® implants (Implant Innovations, Inc., Palm Beach Gardens, FL, USA) to machined-surfaced implants. Materials and Methods: Admission criteria were the same for both data sets. Baseline variables of demographics including age, gender and smoking status, bone quality, location, implant dimensions, and types of prostheses were compared to ensure balance among groups. Cumulative survival rates (CSRs) were calculated with the Kaplan-Meier estimator. Results: The implant data included 2,294 implants for the DAE series and 2,597 implants for the machined-surfaced series. Patient demographics showed similar percentages of occurrence for all variables. The distributions of implants between short- and standard-length data sets for baseline variables including width, location, and restorative type were similar, qualifying these data sets for comparison of the independent variable of length. Overall, there was a 2.2% difference in 5-year CSRs between the machined-surfaced short- and the standard-length implants. For these implants a 7.1% difference was observed in the posterior maxilla and an 8.5% difference in the anterior maxilla. For DAE implants the overall difference between "standards" and "shorts" was 0.7%, which is not statistically significant. Conclusion: In this analysis the difference in CSRs between short- and standard-length implants was greater for machined-surfaced implants than for DAE implants. [source] | |||||||||||||||||||||||||