Rory St John Wolfe

Onset of adolescent eating disorders: population based cohort study over 3 years

Abstract Objective: To study the predictors of new eating disorders in an adolescent cohort. Design: Cohort study over 3 years with six waves. Subjects: Students, initially aged 14-15 years, from 44 secondary schools in the state of Victoria, Australia. Outcome measures: Weight (kg), height (cm), dieting (adolescent dieting scale), psychiatric morbidity (revised clinical interview schedule), and eating disorder (branched eating disorders test). Eating disorder (partial syndrome) was defined when a subject met two criteria for either anorexia nervosa or bulimia nervosa according to the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV). Results: At the start of the study, 3.3% (29/888) of female subjects and 0.3% (2/811) of male subjects had partial syndromes of eating disorders. The rate of development of new eating disorder per 1000 person years of observation was 21.8 in female subjects and 6.0 in male subjects. Female subjects who dieted at a severe level were 18 times more likely to develop an eating disorder than those who did not diet, and female subjects who dieted at a moderate level were five times more likely to develop an eating disorder than those who did not diet. Psychiatric morbidity predicted the onset of eating disorder independently of dieting status so that those subjects in the highest morbidity category had an almost sevenfold increased risk of developing an eating disorder. After adjustment for earlier dieting and psychiatric morbidity, body mass index, extent of exercise, and sex were not predictive of new eating disorders. Conclusions: Dieting is the most important predictor of new eating disorders. Differences in the incidence of eating disorders between sexes were largely accounted for by the high rates of earlier dieting and psychiatric morbidity in the female subjects. In adolescents, controlling weight by exercise rather than diet restriction seems to carry less risk of development of eating disorders. Key messages Adolescent females who diet at a severe level are 18 times more likely to develop an eating disorder than those who do not diet, and those who diet at a moderate level are five times more likely to develop an eating disorder High levels of psychiatric morbidity in females increase the risk of developing eating disorders by sevenfold Around two thirds of new cases of eating disorder arise in females who have dieted moderately The predominance of eating disorders in females is largely explained by the higher rates of earlier dieting and psychiatric morbidity Daily exercise seems to be a less risky strategy for controlling weight in adolescents

Depression, anxiety, and smoking initiation: a prospective study over 3 years.

OBJECTIVES This report considers the extent to which depression and anxiety predict smoking onset in adolescence. METHODS A 6-wave cohort design was used to study a sample of 14- and 15-year-old students (n = 2032) drawn from 44 secondary schools in the state of Victoria, Australia. The students were surveyed between 1992 and 1995 with a computerized questionnaire that included a 7-day retrospective diary for tobacco use and a structured psychiatric interview. RESULTS Experimental smokers were 29 times more likely than non-smokers to make a transition into daily use in the subsequent 6 months. Depression and anxiety, along with peer smoking, predicted initiation of experimental smoking. Specifically, depression and anxiety accentuated risks associated with peer smoking and predicted experimentation only in the presence of peer smoking. CONCLUSIONS The finding that experimental smoking is an overwhelmingly strong predictor of later daily smoking focuses attention on smoking initiation. Depressive and anxiety symptoms are associated with higher risks for initiation through an increased susceptibility to peer smoking influences. Promoting the psychological well-being of adolescents and addressing perceived interpersonal benefits of smoking may play a role in the prevention of adolescent tobacco use.

Sagittal gait patterns in spastic diplegia

Classifications of gait patterns in spastic diplegia have been either qualitative, based on clinical recognition, or quantitative, based on cluster analysis of kinematic data. Qualitative classifications have been much more widely used but concerns have been raised about the validity of classifications, which are not based on quantitative data. We have carried out a cross-sectional study of 187 children with spastic diplegia who attended our gait laboratory and devised a simple classification of sagittal gait patterns based on a combination of pattern recognition and kinematic data. We then studied the evolution of gait patterns in a longitudinal study of 34 children who were followed for more than one year and demonstrated the reliability of our classification.

Genetic Counseling and Prenatal Diagnosis for the Mitochondrial DNA Mutations at Nucleotide 8993

Mitochondrial genetics is complicated by heteroplasmy, or mutant load, which may be from 1%-99%, and thus may produce a gene dosage-type effect. Limited data are available for genotype/phenotype correlations in disorders caused by mtDNA mutations; therefore, prenatal diagnosis for mtDNA mutations has been hindered by an inability to predict accurately the clinical severity expected from a mutant load measured in fetal tissue. After reviewing 44 published and 12 unpublished pedigrees, we considered the possibility of prenatal diagnosis for two common mtDNA mutations at nucleotide 8993. We related the severity of symptoms to the mutant load and predicted the clinical outcome of a given mutant load. We also used the available data to generate empirical recurrence risks for genetic counseling, which may be used in conjunction with prenatal diagnosis.

Correction of severe crouch gait in patients with spastic diplegia with use of multilevel orthopaedic surgery.

BACKGROUND Severe crouch gait in patients with spastic diplegia causes excessive loading of the patellofemoral joint and may result in anterior knee pain, gait deterioration, and progressive loss of function. Multilevel orthopaedic surgery has been used to correct severe crouch gait, but no cohort studies or long-term results have been reported, to our knowledge. METHODS In order to be eligible for the present retrospective cohort study, a patient had to have a severe crouch gait, as defined by sagittal plane kinematic data, that had been treated with multilevel orthopaedic surgery as well as a complete clinical, radiographic, and instrumented gait analysis assessment. The surgical intervention consisted of lengthening of contracted muscle-tendon units and correction of osseous deformities, followed by the use of ground-reaction ankle-foot orthoses until stable biomechanical realignment of the lower limbs during gait was achieved. Outcome at one and five years after surgery was determined with use of selected sagittal plane kinematic and kinetic parameters and valid and reliable scales of functional mobility. Knee pain was recorded with use of a Likert scale, and all patients had radiographic examination of the knees. RESULTS Ten subjects with severe crouch gait and a mean age of 12.0 years at the time of surgery were studied. After surgery, the patients walked in a more extended posture, with increased extension at the hip and knee and reduced dorsiflexion at the ankle. Pelvic tilt increased, and normalized walking speed was unaltered. Knee pain was diminished, and patellar fractures and avulsion injuries healed. Improvements in functional mobility were found, and, at the time of the five-year follow-up, fewer patients required the use of wheelchairs or crutches in the community than had been the case prior to intervention. CONCLUSIONS Multilevel orthopaedic surgery for older children and adolescents with severe crouch gait is effective for relieving stress on the knee extensor mechanism, reducing knee pain, and improving function and independence.

Biomechanical transformation of the gastroc-soleus muscle with botulinum toxin A in children with cerebral palsy.

Objective measures (kinematics and kinetics) were used to study prospectively the effects of botulinum toxin A (BTX/A) on the gastroc‐soleus muscle in ambulant children with cerebral palsy. In this prospective before and after trial, 15 children with diplegia and 10 children with hemiplegia were studied (mean age 5 years 7 months, range 4 years to 9 years). A range of standardized clinical measures was undertaken but the emphasis for this report is on the three‐dimensional gait analysis (3DGA) results. All children showed improvements in sagittal ankle kinematics, as has been previously reported. Two new measures of ankle kinetics were devised: ankle moment quotient (AMQ), and ankle power quotient (APQ). Before intervention, ankle moments were characterized by a‘double bump’ankle moment. A typical abnormal baseline ankle‐power curve was triphasic with an initial trough of absorption followed by abnormal mid‐stance power generation, instead of the usual A1 pattern, and reduced terminal stance power generation (A2). Three weeks after treatment with BTX/A alone there was a statistically significant improvement of AMQ and APQ; some patients required potentiation of BTX/A with a short period of serial casts. Both groups (BTX/A alone and BTX/A plus casting) continued to show improvement in ankle kinetics from baseline after 12 and 24 weeks. This is the first study to demonstrate improvements in the typical abnormal ankle kinetics which we believe provides evidence of the ‘biomechanical transformation of muscle’.

Excellent long-term functional outcome after an operation for anomalous left coronary artery from the pulmonary artery

OBJECTIVE The aim of this study was to review the results of operations for anomalous left coronary artery from the pulmonary artery and the late outcome for exercise capacity, left ventricular function, and mitral regurgitation. METHODS Twenty-one patients underwent operations over an 18-year period (median age, 9 months; range, 6 weeks-26 years) with a median follow-up of 6.5 years (range, 2 months-18 years). In addition to clinical and echocardiographic follow-up, patients at our institution were also investigated with radionuclide scans (n = 10) and treadmill exercise testing (n = 8). RESULTS There were no operative or late deaths (0%; 95% confidence interval [CI], 0% and 16%). Five patients required support with a left ventricular assist device. Eighteen patients are currently in New York Heart Association class I, and 3 patients are mildly symptomatic. On nuclear gated scan at a mean of 6 years after the operation, the left ventricular ejection fraction was 64% (SD, 3%) at rest and increased to 74% (SD = 3%) on exercise (95% CI for the difference, 6%, 14%; P =.001). Treadmill endurance was normal for age (9.8-14.5 minutes) in those old enough to exercise. On echocardiography (n = 18), the current fractional shortening was 34% (SD, 4%) in the 15 patients with normal or only mildly abnormal ventricular septal motion. Three patients have undergone mitral valve operations. The left ventricular end-diastolic dimension fell from 48 mm (SD, 5.8 mm) before surgery to 35.1 mm (SD, 5.2 mm) at 1 year after the operation, and the fractional shortening increased over the first year from 19.6% (SD, 9.3%) to 32.8% (SD, 5.9%; both P <.001). CONCLUSIONS Long-term clinical outcome and left ventricular function are good, despite severe left ventricular dysfunction at presentation.

A randomized controlled trial of the impact of therapeutic horse riding on the quality of life, health, and function of children with cerebral palsy

This randomized controlled trial examined whether therapeutic horse riding has a clinically significant impact on the physical function, health and quality of life (QoL) of children with cerebral palsy (CP). Ninety‐nine children aged 4 to 12 years with no prior horse riding experience and various levels of impairment (Gross Motor Function Classification System Levels I−III) were randomized to intervention (10wks therapeutic programme; 26 males, 24 females; mean age 7y 8mo [SD 2y 5mo] or control (usual activities, 27 males, 22 females; mean age 8y 2mo [SD 2y 6mo]). Pre‐ and post‐measures were completed by 72 families (35 intervention and 37 control). Children’s gross motor function (Gross Motor Function Measure [GMFM]), health status (Child Health Questionnaire [CHQ]), and QoL (CP QoL‐Child, KIDSCREEN) were assessed by parents and QoL was assessed by children before and after the 10‐week study period. On analysis of covariance, there was no statistically significant difference in GMFM, CP QoL‐Child (parent report and child self‐report), and CHQ scores (except family cohesion) between the intervention and control group after the 10‐week study period, but there was weak evidence of a difference for KIDSCREEN (parent report). This study suggests that therapeutic horse riding does not have a clinically significant impact on children with CP. However, a smaller effect cannot be ruled out and the absence of evidence might be explained by a lack of sensitivity of the instruments since the QoL and health measures have not yet been demonstrated to be sensitive to change for children with CP.

The Duration of Obesity and the Risk of Type-2 Diabetes

OBJECTIVE The evidence for the association between obesity and the risk of type 2 diabetes has been derived mainly from the analysis of the degree of obesity. The role of the duration of obesity as an independent risk has not been fully explored. The objective of the present study was to investigate the association between the duration of obesity and the risk of type 2 diabetes. DESIGN Prospective cohort study. SETTING The Framingham Heart Study (FHS), follow-up from 1948 to 1998. SUBJECTS A total of 1256 FHS participants who were free from type 2 diabetes at baseline, but were obese on at least two consecutive of the studys twenty-four biennial examinations, were included. Type 2 diabetes status was collected throughout the 48 years of follow-up of the study. The relationship between duration of obesity and type 2 diabetes was analysed using time-dependent Cox models, adjusting for a number of covariates. RESULTS The unadjusted hazard ratio (HR) for the risk of type 2 diabetes for men was 1.13 (95 % CI 1.09, 1.17) and for women was 1.12 (95 % CI 1.08, 1.16) per additional 2-year increase in the duration of obesity. Adjustment for sociodemographic variables, family history of diabetes, health behaviour and physical activity made little difference to these HR. For women the evidence of a dose-response relationship was less clear than for men, particularly for women with an older age at obesity onset. CONCLUSIONS The duration of obesity is a relevant risk factor for type 2 diabetes, independent of the degree of BMI.

Risk Factors for New Detection of Vancomycin-Resistant Enterococci in Acute-Care Hospitals That Employ Strict Infection Control Procedures

ABSTRACT Accurate assessment of the risk factors for colonization with vancomycin-resistant enterococci (VRE) among high-risk patients is often confounded by nosocomial VRE transmission. We undertook a 15-month prospective cohort study of adults admitted to high-risk units (hematology, renal, transplant, and intensive care) in three teaching hospitals that used identical strict infection control and isolation procedures for VRE to minimize nosocomial spread. Rectal swab specimens for culture were regularly obtained, and the results were compared with patient demographic factors and antibiotic exposure data. Compliance with screening was defined as “optimal” (100% compliance) or “acceptable” (minor protocol violations were allowed, but a negative rectal swab specimen culture was required within 1 week of becoming colonized with VRE). Colonization with VRE was detected in 1.56% (66 of 4,215) of admissions (0.45% at admission and 0.83% after admission; the acquisition time was uncertain for 0.28%), representing 1.91% of patients. No patients developed infection with VRE. The subsequent rate of new acquisition of VRE was 1.4/1,000 patient days. Renal units had the highest rate (3.23/1,000 patient days; 95% confidence interval [CI], 1.54 to 6.77/1,000 patient days). vanB Enterococcus faecium was the most common species (71%), but other species included vanB Enterococcus faecalis (21%), vanA E. faecium (6%), and vanA E. faecalis (2%). The majority of isolates were nonclonal by pulsed-field gel electrophoresis analysis. Multivariate analysis of risk factors in patients with an acceptable screening suggested that being managed by a renal unit (hazard ratio [HR] compared to the results for patients managed in an intensive care unit, 4.6; 95% CI, 1.2 to 17.0 [P = 0.02]) and recent administration of either ticarcillin-clavulanic acid (HR, 3.6; 95% CI, 1.1 to 11.6 [P = 0.03]) or carbapenems (HR, 2.8; 95% CI, 1.0, 8.0 [P = 0.05]), but not vancomycin or broad-spectrum cephalosporins, were associated with acquisition of VRE. The relatively low rates of colonization with VRE, the polyclonal nature of most isolates, and the possible association with the use of broad-spectrum antibiotics are consistent with either the endogenous emergence of VRE or the amplification of previously undetectable colonization with VRE among high-risk patients managed under conditions in which the risk of nosocomial acquisition was minimized.