Endel John Orav

Female Sex and Higher Drug Dose as Risk Factors for Late Cardiotoxic Effects of Doxorubicin Therapy for Childhood Cancer

BACKGROUND Late cardiotoxic effects of doxorubicin are increasingly a problem for patients who survive childhood cancer. Cardiotoxicity is often progressive, and some patients have disabling symptoms. Our objective was to identify risk factors for late cardiotoxicity. METHODS We examined echocardiograms from 120 children and adults who had received cumulative doses of 244 to 550 mg of doxorubicin per square meter of body-surface area for the treatment of acute lymphoblastic leukemia or osteogenic sarcoma in childhood, a mean of 8.1 years earlier. Measurements of blood pressure and left ventricular function, contractility (measured as the stress-velocity index), end-diastolic posterior-wall thickness, end-diastolic dimension, mass, and afterload (measured as end-systolic wall stress) were compared with sex-specific values from a cohort of 296 normal subjects. RESULTS All echocardiographic measurements were abnormal at follow-up a minimum of two years after the end of therapy, with more frequent and severe abnormalities in female patients. In a multivariate analysis, female sex and a higher cumulative dose of doxorubicin were associated with depressed contractility (P < or = 0.001), and there was an interaction between these two variables. Independent and significant associations were found between a higher rate of administration of doxorubicin and increased afterload (P < or = 0.001), left ventricular dilatation, and depressed left ventricular function; between a higher cumulative dose and depressed left ventricular function (P < or = 0.001); between a younger age at diagnosis and reduced left-ventricular-wall thickness and mass and increased afterload; and between a longer time since the completion of doxorubicin therapy and reduced left-ventricular-wall thickness and increased afterload (P < or = 0.001). CONCLUSIONS Female sex and a higher rate of administration of doxorubicin were independent risk factors for cardiac abnormalities after treatment with doxorubicin for childhood cancer; the prevalence and severity of abnormalities increased with longer follow-up.

A Pooled Analysis of Vitamin D Dose Requirements for Fracture Prevention

BACKGROUND The results of meta-analyses examining the relationship between vitamin D supplementation and fracture reduction have been inconsistent. METHODS We pooled participant-level data from 11 double-blind, randomized, controlled trials of oral vitamin D supplementation (daily, weekly, or every 4 months), with or without calcium, as compared with placebo or calcium alone in persons 65 years of age or older. Primary end points were the incidence of hip and any nonvertebral fractures according to Cox regression analyses, with adjustment for age group, sex, type of dwelling, and study. Our primary aim was to compare data from quartiles of actual intake of vitamin D (including each individual participants adherence to the treatment and supplement use outside the study protocol) in the treatment groups of all trials with data from the control groups. RESULTS We included 31,022 persons (mean age, 76 years; 91% women) with 1111 incident hip fractures and 3770 nonvertebral fractures. Participants who were randomly assigned to receive vitamin D, as compared with those assigned to control groups, had a nonsignificant 10% reduction in the risk of hip fracture (hazard ratio, 0.90; 95% confidence interval [CI], 0.80 to 1.01) and a 7% reduction in the risk of nonvertebral fracture (hazard ratio, 0.93; 95% CI, 0.87 to 0.99). By quartiles of actual intake, reduction in the risk of fracture was shown only at the highest intake level (median, 800 IU daily; range, 792 to 2000), with a 30% reduction in the risk of hip fracture (hazard ratio, 0.70; 95% CI, 0.58 to 0.86) and a 14% reduction in the risk of any nonvertebral fracture (hazard ratio, 0.86; 95% CI, 0.76 to 0.96). Benefits at the highest level of vitamin D intake were fairly consistent across subgroups defined by age group, type of dwelling, baseline 25-hydroxyvitamin D level, and additional calcium intake. CONCLUSIONS High-dose vitamin D supplementation (≥800 IU daily) was somewhat favorable in the prevention of hip fracture and any nonvertebral fracture in persons 65 years of age or older. (Funded by the Swiss National Foundations and others.).

The “To Err is Human” report and the patient safety literature

Background: The “To Err is Human” report published by the Institute of Medicine (IOM) in 1999 called for a national effort to make health care safer. Although the report has been widely credited with spawning efforts to study and improve safety in health care, there has been limited objective assessment of its impact. We evaluated the effects of the IOM report on patient safety publications and research awards. Methods: We searched MEDLINE to identify English language articles on patient safety and medical errors published between 1 November 1994 and 1 November 2004. Using interrupted time series analyses, changes in the number, type, and subject matter of patient safety publications were measured. We also examined federal (US only) funding of patient safety research awards for the fiscal years 1995–2004. Results: A total of 5514 articles on patient safety and medical errors were published during the 10 year study period. The rate of patient safety publications increased from 59 to 164 articles per 100 000 MEDLINE publications (p<0.001) following the release of the IOM report. Increased rates of publication were observed for all types of patient safety articles. Publications of original research increased from an average of 24 to 41 articles per 100 000 MEDLINE publications after the release of the report (p<0.001), while patient safety research awards increased from 5 to 141 awards per 100 000 federally funded biomedical research awards (p<0.001). The most frequent subject of patient safety publications before the IOM report was malpractice (6% v 2%, p<0.001) while organizational culture was the most frequent subject (1% v 5%, p<0.001) after publication of the report. Conclusions: Publication of the report “To Err is Human” was associated with an increased number of patient safety publications and research awards. The report appears to have stimulated research and discussion about patient safety issues, but whether this will translate into safer patient care remains unknown.

National Institutes of Health state-of-the-science conference statement: prevention of fecal and urinary incontinence in adults.

The ramifications of fecal incontinence and urinary incontinence extend well beyond their physical manifestations. To promote work that will reduce suffering and costs attributable to fecal and uri...

Performance of generalized estimating equations in practical situations.

Moment methods for analyzing repeated binary responses have been proposed by Liang and Zeger (1986, Biometrika 73, 13-22), and extended by Prentice (1988, Biometrics 44, 1033-1048). In their generalized estimating equations (GEE), both Liang and Zeger (1986) and Prentice (1988) estimate the parameters associated with the expected value of an individuals vector of binary responses as well as the correlations between pairs of binary responses. In this paper, we discuss one-step estimators, i.e., estimators obtained from one step of the generalized estimating equations, and compare their performance to that of the fully iterated estimators in small samples. In simulations, we find the performance of the one-step estimator to be qualitatively similar to that of the fully iterated estimator. When the sample size is small and the association between binary responses is high, we recommend using the one-step estimator to circumvent convergence problems associated with the fully iterated GEE algorithm. Furthermore, we find the GEE methods to be more efficient than ordinary logistic regression with variance correction for estimating the effect of a time-varying covariate.

Effect of High-Dosage Cholecalciferol and Extended Physiotherapy on Complications After Hip Fracture: A Randomized Controlled Trial

BACKGROUND Care of elderly patients after hip fracture is not well established. METHODS We enrolled 173 patients with acute hip fracture who were 65 years or older (79.2% women; mean age, 84 years; 77.4% living at home). Using a factorial design, we randomly allocated patients to extended physiotherapy (PT) (supervised 60 min/d during acute care plus an unsupervised home program) vs standard PT (supervised 30 min/d during acute care plus no home program; single-blinded), and to cholecalciferol therapy, 2000 vs 800 IU/d (double-blinded). Primary outcome was rate of falls; secondary outcome was rate of hospital readmissions during the 12-month follow-up. All analyses included 173 individuals and used multivariate Poisson regression analyses. RESULTS At baseline, 50.9% of participants had 25-hydroxyvitamin D levels of less than 12 ng/mL and 97.7% of less than 30 ng/mL. We documented 212 falls and 74 hospital readmissions. Because this was a factorial design trial, all analyses tested the main effect of each treatment while controlling for the other in 173 participants. Extended vs standard PT reduced the rate of falls by 25% (95% confidence interval [CI], -44% to -1%). Cholecalciferol treatment, 2000 vs 800 IU/d, did not reduce falls (28%; 95% CI, -4% to 68%), but reduced the rate of hospital readmissions by 39% (95% CI, -62% to -1%). CONCLUSIONS Extended PT was successful in reducing falls but not hospital readmissions, whereas cholecalciferol treatment, 2000 IU/d, was successful in reducing hospital readmission but not falls. Thus, the 2 strategies may be useful together because they address 2 different and important complications after hip fracture.

NONURGENT EMERGENCY DEPARTMENT VISITS : THE EFFECT OF HAVING A REGULAR DOCTOR

OBJECTIVES The authors assess the association between having a regular doctor and presentation for nonurgent versus urgent emergency department visits while controlling for potential confounders such as sociodemographics, health status, and comorbidity. METHODS A cross-sectional study was conducted in emergency departments of five urban teaching hospitals in the northeast. Adult patients presenting with chest pain, abdominal pain, or asthma (n = 1696; 88% of eligible) were studied. Patients completed a survey on presentation, reporting sociodemographics, health status, comorbid diseases, and relationship with a regular doctor. Urgency on presentation was assessed by chart review using explicit criteria. RESULTS Of the 1,696 study participants, 852 (50%) presented with nonurgent complaints. In logistic regression analyses, absence of a relationship with a regular physician was an independent correlate of presentation for a nonurgent emergency department visit (odds ratio 1.6; 95% confidence interval 1.2, 2.2) when controlling for age, gender, marital status, health status, and comorbid diseases. Race, lack of insurance, and education were not associated with nonurgent use. CONCLUSIONS Absence of a relationship with a regular doctor was correlated with use of the emergency department for selected nonurgent conditions when controlling for important potential confounders. Our study suggests that maintaining a relationship with a regular physician may reduce nonurgent use of the emergency department regardless of insurance status or health status.

Statin use and risk of prostate cancer in the California Men's Health Study cohort.

Statins have known anticarcinogenic effects, however, evidence for long-term statin use as effective chemoprevention for prostate cancer is inconsistent. We examined the association between statin use and risk of prostate cancer among 69,047 eligible participants in the California Mens Health Study, a prospective cohort of Northern and Southern California Kaiser Permanente (KP) members, ages 45 to 69 years, initiated in 2002. Prostate cancer cases were identified by linkage to the KP California Cancer Registries. Statin exposure, estimated from automated KP outpatient pharmacy records (available since 1991 in Southern California and since 1994 in Northern California), was treated as time-varying and defined as the cumulative days dispensed of any statin from the first dispensing until a prostate cancer diagnosis, radical prostatectomy, termination of membership, or end of study (December 31, 2004). Cox proportional hazards models with age as the time scale were used to estimate rate ratios, while controlling for confounding variables. During follow-up, 888 prostate cancer cases, including 131 advanced cases, were identified. There was no association between ever statin use or <5 years use and prostate cancer. Conversely, ≥5 years use was associated with a 28% lower risk for prostate cancer compared with nonuse (adjusted rate ratio, 0.72; 95% confidence interval, 0.53-0.99). This association did not differ markedly for advanced disease. However, the association did seem to be restricted to those who regularly take nonsteroidal anti-inflammatory drugs. Our findings suggest that long-term statin use might be associated with a reduced risk of prostate cancer but perhaps only among regular nonsteroidal anti-inflammatory drug users. (Cancer Epidemiol Biomarkers Prev 2007;16(11):2218–25)

Echocardiographic Strain Imaging to Assess Early and Late Consequences of Sarcomere Mutations in Hypertrophic Cardiomyopathy

Background—Genetic testing identifies sarcomere mutation carriers (G+) before clinical diagnosis of hypertrophic cardiomyopathy (HCM), allowing characterization of initial disease manifestations. Previous studies demonstrated that impaired relaxation develops before left ventricular hypertrophy (LVH). The precise impact of sarcomere mutations on systolic function in early and late disease is unclear. Methods and Results—Comprehensive echocardiography with strain imaging was performed on 146 genotyped individuals with mutations in 5 sarcomere genes. Contractile parameters were compared in 68 preclinical (G+/LVH−), 40 overt (G+/LVH+) subjects with HCM, and 38 mutation (−) normal control relatives. All subjects had normal left ventricular ejection fraction. In preclinical HCM, global and regional peak systolic strain (ϵsys) and longitudinal systolic strain rate were not significantly different from controls, but early diastolic mitral annular velocity (Ea) was reduced by 13%. In overt HCM, there was a significant 27% and 14% decrease in global longitudinal ϵsys and systolic strain rate, respectively, compared with both preclinical HCM and controls (P<0.013 for all comparisons), and a 33% reduction in Ea. Conclusions—Sarcomere mutations have disparate initial effects on diastolic and systolic functions. Preclinical HCM is characterized by impaired relaxation but preserved systolic strain. In contrast, both diastolic and longitudinal systolic abnormalities are present in overt disease despite normal ejection fraction. We propose that diastolic dysfunction is an early consequence of sarcomere mutations, whereas systolic dysfunction results from mutations combined with subsequent pathological remodeling. Identifying mechanistic pathways triggered by these mutations may begin to reshape the clinical paradigm for treatment, based on early diagnosis and disease prevention.

Milk intake and risk of hip fracture in men and women: A meta-analysis of prospective cohort studies

Milk contains calcium, phosphorus, and protein and is fortified with vitamin D in the United States. All these ingredients may improve bone health. However, the potential benefit of milk on hip fracture prevention is not well established. The objective of this study was to assess the association of milk intake with risk of hip fracture based on a meta‐analysis of cohort studies in middle‐aged or older men and women. Data sources for this study were English and non‐English publications via Medline (Ovid, PubMed) and EMBASE search up to June 2010, experts in the field, and reference lists. The idea was to compare prospective cohort studies on the same scale so that we could calculate the relative risk (RR) of hip fracture per glass of milk intake daily (approximately 300 mg calcium per glass of milk). Pooled analyses were based on random effects models. The data were extracted by two independent observers. The results show that in women (6 studies, 195,102 women, 3574 hip fractures), there was no overall association between total milk intake and hip fracture risk (pooled RR per glass of milk per day = 0.99; 95% confidence interval [CI] 0.96–1.02; Q‐test p = .37). In men (3 studies, 75,149 men, 195 hip fractures), the pooled RR per daily glass of milk was 0.91 (95% CI 0.81–1.01). Our conclusion is that in our meta‐analysis of cohort studies, there was no overall association between milk intake and hip fracture risk in women but that more data are needed in men.