Obesity and non-fatal motor vehicle crash injuries: sex difference effects.

BACKGROUND: Obesity and motor vehicle crash (MVC) injuries are two parallel epidemics in the United States. An important unanswered question is whether there are sex differences in the associations between the presence of obesity and non-fatal MVC injuries. OBJECTIVES: To further understand the association between obesity and non-fatal MVC injuries, particularly the sex differences in these relations. METHODS: We examined this question by analyzing data from the 2003 to 2007 National Automotive Sampling System Crashworthiness Data System (NASS CDS). A total of 10,962 drivers who were aged 18 years or older and who survived frontal collision crashes were eligible for the study. RESULTS: Male drivers experienced a lower rate of overall non-fatal MVC injuries than did female drivers (38.1 versus 52.2%), but experienced a higher rate of severe injuries (0.7 versus 0.2%). After adjusting for change in velocity (ΔV) during the crashes, obese male drivers showed a much higher risk (logistic coefficients of body mass index (BMI) for moderate, serious and severe injury are 0.0766, 0.1470 and 0.1792, respectively; all P<0.05) of non-fatal injuries than did non-obese male drivers and these risks increased with injury severity. Non-fatal injury risks were not found to be increased in obese female drivers. The association between obesity and risk of non-fatal injury was much stronger for male drivers than for female drivers. CONCLUSION: The higher risk of non-fatal MVC injuries in obese male drivers might result from their different body shape and fat distribution compared with obese female drivers. Our findings should be considered for obesity reduction, traffic safety evaluation and vehicle design for obese male drivers and provide testable hypotheses for future studies.

Patient risk factors for medical injury: a case-control study.

OBJECTIVE: To determine risk factors of medical injury, defined as untoward injury from diagnostic or therapeutic healthcare interventions. Identifying risk factors for medical injuries could inform the development of preventive interventions. METHODS: A hospital-based case-control study. Cases and controls were selected among patients discharged from a large Midwestern teaching hospital between 1 January 2003 and 31 December 2004. Cases (n=268) were selected in a three-step process. First, medical injuries in the discharge database were identified using the Wisconsin Medical Injury Prevention Programme Surveillance Criteria. Second, provisional cases were randomly chosen from patients flagged with a medical injury. Provisional controls were randomly selected from patients not flagged with a medical injury, matching for Diagnosis Related Group of the provisional cases. Third, a chart review determined ultimate case-control status. Severity of illness and risk of mortality were calculated using the All Patients Refined-Diagnosis Related Groups system. Zahn's comorbidity score was calculated. Conditional logistic regressions were run with injury status as the dependent variable. RESULTS: Among the 268 cases, 47.8% were procedure-related injuries and 44.8% were medication-related injuries. Conditional logistic regressions found higher severity of illness and higher risks of mortality were related to risk of medical injury (OR 3.29 (95% CI 1.05 to 10.31) and OR 5.16 (95% CI 1.42 to 18.79), respectively). Additional regressions showed the Zahn comorbidity score related to the risk of medical injury (OR 1.63, 95% CI 1.31 to 2.02). CONCLUSIONS: Patients with higher severity of illness, higher risk of inpatient mortality and multiple comorbidities are at increased risk for a medical injury.

Fracture risk and adjuvant hormonal therapy among a population-based cohort of older female breast cancer patients.

UNLABELLED: The risk of hip and other fractures was examined among a population-based group of older women with breast cancer. Women using aromatase inhibitors (AIs) were found to be over three times more likely to have a hip fracture over approximately 3 years' follow-up. Other fracture risk factors were also identified. INTRODUCTION: Aromatase inhibitors have been shown in randomized trials to increase total fracture risk compared with tamoxifen, but the fracture risks in the trials were relatively low, and no difference in hip fracture has been demonstrated. METHODS: A population-based cohort of 2003 breast cancer survivors ≥65 were followed prospectively for a median of 36 months. Patient survey information regarding adjuvant breast cancer therapies, prescription osteoporosis treatments, and other factors potentially associated with fracture was supplemented with cancer registry information. Hip and total nonvertebral fractures were determined using a validated Medicare algorithm, and the association of these fractures with adjuvant hormonal therapies was examined using Cox models. RESULTS: The cohort of 2,748 women with a mean age of 72.8 (SD 5.4) included 28.2% who took an aromatase inhibitor and 27.8% tamoxifen. There were 41 hip fractures (1.5%) and 218 nonvertebral fractures (7.9%) among the cohort. Subjects using AIs (adjusted hazard ratio 3.24 (1.05, 9.98)) and subjects not using hormone therapy (3.32 (1.14, 9.65)) were more likely than users of tamoxifen to have a hip fracture. Bisphosphonate use was more common among AI users but did not explain these results. Users of AIs were more likely to have nonvertebral fractures, but this result did not reach statistical significance (adjusted hazard 1.34 (0.92, 1.94)). CONCLUSIONS: Hip and other fractures were common in an older population-based cohort of breast cancer survivors, and aromatase inhibitor use was associated with an increase in the short-term risk of hip fractures not detected in randomized controlled trials.

Incidence of sports and recreation related injuries resulting in hospitalization in Wisconsin in 2000.

OBJECTIVE: To describe the incidence and patterns of sports and recreation related injuries resulting in inpatient hospitalization in Wisconsin. Although much sports and recreation related injury research has focused on the emergency department setting, little is known about the scope or characteristics of more severe sports injuries resulting in hospitalization. SETTING: The Wisconsin Bureau of Health Information (BHI) maintains hospital inpatient discharge data through a statewide mandatory reporting system. The database contains demographic and health information on all patients hospitalized in acute care non-federal hospitals in Wisconsin. METHODS: The authors developed a classification scheme based on the International Classification of Diseases External cause of injury code (E code) to identify hospitalizations for sports and recreation related injuries from the BHI data files (2000). Due to the uncertainty within E codes in specifying sports and recreation related injuries, the authors used Bayesian analysis to model the incidence of these types of injuries. RESULTS: There were 1714 (95% credible interval 1499 to 2022) sports and recreation-related injury hospitalizations in Wisconsin in 2000 (32.0 per 100,000 population). The most common mechanisms of injury were being struck by/against an object in sports (6.4 per 100,000 population) and pedal cycle riding (6.2 per 100,000). Ten to 19 year olds had the highest rate of sports and recreation related injury hospitalization (65.3 per 100,000 population), and males overall had a rate four times higher than females. CONCLUSIONS: Over 1700 sports and recreation related injuries occurred in Wisconsin in 2000 that were treated during an inpatient hospitalization. Sports and recreation activities result in a substantial number of serious, as well as minor injuries. Prevention efforts aimed at reducing injuries while continuing to promote participation in physical activity for all ages are critical.

The presence or absence of an impalpable testis can be predicted from clinical observations alone.

OBJECTIVE: To evaluate, in a prospective study, the accuracy of predicting the presence or absence of unilateral or bilateral impalpable testes from a clinical examination, particularly whether the contralateral descended testis (CDT) is hypertrophied. PATIENTS AND METHODS: Whether the ipsilateral scrotal appendages were palpable, and the size of the CDT, were determined before surgery in a series of patients, and compared with age-matched controls. Between 1992 and 2000, 100 impalpable testes in 86 consecutive patients (mean age at orchidopexy 45 months, range 6-223; 66% <36 months) were evaluated and treated. In addition to the presence or absence of palpable ipsilateral scrotal appendages, the size of the CDT, when present, and the intraoperative findings were recorded. Logistic regression analysis was used to model the probability of the presence or absence of the testis, as determined by the preoperative clinical findings alone. RESULTS: Of the 86 testes that were located at surgery, 50 (58%) were intracanalicular, 28 (32%) intra-abdominal and the remainder (10%) were in the superficial inguinal pouch. Of 13 patients with the 'vanishing testis syndrome', the atrophic testicle was intracanalicular in nine, in the upper scrotum in three and intra-abdominal in only one. All viable testes were successfully relocated in the scrotum, with one atrophic after surgery. The positive predictive value (PPV, with 95% confidence interval) of a testis being present when the ipsilateral appendages were palpable and the CDT was not hypertrophied was 0.93 (0.83-0.97). Conversely, the PPV of the impalpable testis being absent when the appendages were impalpable and the CDT was hypertrophied was 0.95 (0.64-0.99). CONCLUSION: When evaluating and surgically treating impalpable testes, the presence of palpable ipsilateral scrotal appendages and a CDT with no hypertrophy is associated with a 93% likelihood of discovering a testis that can be successfully relocated to the scrotum. Conversely, when the ipsilateral scrotal appendages cannot be palpated and the CDT is hypertrophied, there is a 96% probability that the impalpable testis is absent (vanishing testis syndrome). This readily available information may be valuable in preoperative counselling and planning.

Probabilistic cost-effectiveness analysis of HIV prevention. Comparing a Bayesian approach with traditional deterministic sensitivity analysis.

In cost-effectiveness analysis, the incremental cost-effectiveness ratio is used to measure economic efficiency of a new intervention, relative to an existing one. However, costs and effects are seldom known with certainty. Uncertainty arises from two main sources: uncertainty regarding correct values of intervention-related parameters and uncertainty associated with sampling variation. Recently, attention has focused on Bayesian techniques for quantifying uncertainty. We computed the Bayesian-based 95% credible interval estimates of the incremental cost-effectiveness ratio of several related HIV prevention interventions and compared these results with univariate sensitivity analyses. The conclusions were comparable, even though the probabilistic technique provided additional information.

Economics of managed care in spinal cord injury.

OBJECTIVE: To determine and describe trends in economic variables related to the care of individuals with spinal cord injury (SCI) and significant changes in these trends coincident with major developments in medical care cost control. DATA SOURCES: Data from the National Spinal Cord Injury Statistical Center (NSCISC) database were used to review the economic trends in SCI management from 1973 to 1998 and their relation to managed care and other health care cost-containment measures. A panel of SCI health care specialists was interviewed to determine the appropriate data variables to be reviewed. The Shepherd Center Care Health Management Program, Atlanta, GA, is presented as an example of a fiscally successful managed care program for patients with SCI. DATA EXTRACTION: Data from the NSCISC database for the years studied were extracted and converted to a form suitable for analysis by means of the statistical software SAS. DATA SYNTHESIS: Statistical techniques included multiple regression analysis, logistic regression analysis, and model selection methods. CONCLUSIONS: Trends in economic variables, in the care of individuals with SCI show changes coincident with the introduction of Diagnostic Related Groups (DRGs) and managed care as models for provider reimbursement. Significant changes occurred in acute care charges, rehabilitation charges, length of stay, rehospitalization 1 year postinjury, time from injury to admission to a Model System, and discharges to a nursing home.

Influence of genetic and environmental factors on melanocytic naevi: a lesson from Turner's syndrome.

Females with Turner syndrome (TS) are alleged to have increased numbers of melanocytic naevi. Although a high count of acquired melanocytic naevi (AMN) is one of the major risk factors for melanoma, this malignancy has been reported only rarely in patients with TS. The purpose of this study was to explore the effects of environmental and genetic factors on AMN count and density in TS. AMN count and density in 24 patients with TS treated with growth hormone (GH). 24 GH-treated females with GH deficiency (GHD) and 24 normal females were compared in a cross-sectional study. The average AMN density in TS was 50 naevi/m2 as compared with 18 naevi/m2 in the GHD group and 24 naevi/m2 in normal controls (P = 0.001 and P = 0.004, respectively). Duration of GH therapy did not correlate with AMN count (P = 0.44) or AMN density (P = 0.81). The pattern of distribution of naevi between constantly exposed, intermittently exposed and unexposed skin was similar in all groups. Sun exposure was the major factor that affected the regional AMN densities in the control groups, but not in the TS group. The findings of our study indicate that the effects of environmental factors on AMN count and density may vary among genetically different populations. A review of the literature suggested that melanoma is no more prevalent in TS than in the general population.

The normal kidney growth rate during year 1 of life is variable and age dependent.

PURPOSE: The concept of normal contralateral kidney growth rate was introduced as a parameter to consider in conjunction with others in the evaluation of unilateral hydronephrosis in asymptomatic neonates and infants. Historically measurements of renal size obtained at different times from different patients have been relied on to construct normal renal growth charts. We report normal kidney growth rates in year 1 of life derived from interval ultrasound measurements of renal size in the same newborns and infants longitudinally with time. MATERIALS AND METHODS: We reviewed 333 normal renal ultrasound studies performed between 1991 and 1995 in 55 patients during year 1 of life. These longitudinal measurements were made bilaterally 2 to 8 times (median 3) per patient. Growth curve models that consider random patient effects were used to estimate the mean growth curve and ascertain its form. We also reviewed an additional 91 ultrasound studies in 10 patients with myelomeningocele without hydronephrosis or reflux. We analyzed the kidney growth rate in a similar manner and compared the results with those in the normal patients. RESULTS: Analysis of the normal cases revealed a changing growth rate during year 1 of life estimated to be 3.1 mm. per month at birth, decreasing gradually during the first 7 months of life to 0.25 mm. per month and remaining constant thereafter (p = 0.0064). Mean kidney size at birth was estimated to be 42.8 mm. (95% confidence limits 27.0 to 58.5). At age 7 months mean size was 60.7 mm. (95% confidence limits 40.1 to 81.3). CONCLUSIONS: These data demonstrate that normal kidney growth is age dependent. A rapid but slowly decreasing growth rate during the first 7 months of life is followed by a more constant and lower rate. The data also suggest that unusually rapid growth, such as that which may occur in the normal contralateral kidney in unilateral obstruction, may also be age dependent, exceeding 5.0 mm. per month during the first 7 months of life and 2.0 mm. per month thereafter.

Lack of effect of growth hormone therapy on the count and density of melanocytic naevi in children.

An observation of accelerated growth of acquired melanocytic naevi (AMN) during treatment with human growth hormone (GH) raised concerns about the potential risk of melanoma in treated patients. An increased number of AMN, rather than growth rate, is associated with a higher risk for melanoma. It is unknown whether treatment with GH causes an increase in numbers of AMN. We evaluated the effect of GH treatment on the number of AMN in a cross-sectional study of 90 children with GH deficiency. AMN counts and densities in these children were compared with those found in a control group of 100 children. Factors potentially related to increased numbers of AMN, such as age, sex, skin colour, number of episodes of sunburn and duration of GH therapy were determined. Among the various factors, only the age and colour of unexposed skin area were predictive for the total number and density of AMN. No correlation was found between the AMN counts or density and the duration of GH therapy. There was no difference in AMN counts or density between the GH-deficient patient group and the control groups. We conclude that GH therapy in children is not associated with increased AMN count and density and is unlikely to potentiate the risk for melanoma in these children.