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J M Simpson

Publications and source records attributed to J M Simpson.

At least 19 recordsLinked to original sources
PubMed2007

Influence of fall related factors and bone strength on fracture risk in the frail elderly.

INTRODUCTION: When subjects are selected on the basis of fall risk alone, therapies for osteoporosis have not been effective. In a prospective study of elderly subjects at high risk of falls, we investigated the influence of bone strength and fall risk on fracture. METHODS: At baseline we assessed calcaneal bone ultrasound attenuation (BUA) as well as quantitative measures of fall risk in 2005 subjects in residential care. Incident falls and fractures were recorded (median follow-up 705 days). RESULTS: A total of 6646 fall events and 375 low trauma fracture events occurred. The fall rate was 214 per 100 person years and the fracture rate 12.1 per 100 person years. 82% of the fractures could be attributed to falls. Although fracture rates increased with decreasing BUA (incidence rate ratio 1.94 for lowest vs. highest BUA tertile, p<0.002), incident falls also affected fracture incidence. Subjects who fell frequently (>3.15 falls/per person year) were 3.35 times more likely to suffer a fracture than those who did not fall. Some fall risk factors such as balance were associated with the lowest fracture risk lowest in the worst performing group. Multivariate analysis revealed higher fall rate, history of previous fracture, lower BUA, lower body weight, cognitive impairment and better balance as significant independent risk factors for fracture. CONCLUSIONS: In the frail elderly, both skeletal fragility and fall risk including the frequency of exposure to falls are important determinants of fracture risk.

Accidental Falls↗
PubMed2006

Spinal-injured neuropathic bladder antisepsis (SINBA) trial.

OBJECTIVE: To determine whether Methenamine Hippurate (MH) or cranberry tablets prevent urinary tract infections (UTI) in people with neuropathic bladder following spinal cord injury (SCI). STUDY DESIGN: Double-blind factorial-design randomized controlled trial (RCT) with 2 year recruitment period from November 2000 and 6 month follow-up. SETTING: In total, 543 eligible predominantly community dwelling patients were invited to participate in the study, of whom 305 (56%) agreed. METHODS: Eligible participants were people with SCI with neurogenic bladder and stable bladder management. All regimens were indistinguishable in appearance and taste. The dose of MH used was 1 g twice-daily. The dose of cranberry used was 800 mg twice-daily. The main outcome measure was the time to occurrence of a symptomatic UTI. RESULTS: Multivariate analysis revealed that patients randomized to MH did not have a significantly longer UTI-free period compared to placebo (HR 0.96, 95% CI: 0.68-1.35, P=0.75). Patients randomized to cranberry likewise did not have significantly longer UTI-free period compared to placebo (HR 0.93, 95% CI: 0.67-1.31, P=0.70). CONCLUSION: There is no benefit in the prevention of UTI from the addition of MH or cranberry tablets to the usual regimen of patients with neuropathic bladder following SCI.

Adolescent↗
PubMed2006

Prenatal predictors of mortality in very preterm infants cared for in the Australian and New Zealand Neonatal Network.

AIM: To identify antenatal and perinatal risk factors for in-hospital mortality of babies born within the Australian and New Zealand Neonatal Network (ANZNN). METHODS: Data were collected prospectively as part of the ongoing audit of high-risk infants (birth weight <1500 g or gestation <32 weeks) admitted to all level III neonatal units in Australia and New Zealand. Antenatal and intrapartum factors to 1 min of age were examined in 11 498 infants with gestational age >24 weeks. Risk and protective factors for mortality were derived from logistic regression models fitted to 1998-9 data and validated on 2000-1 data. RESULTS: For the whole cohort of infants born between 1998 and 2001, prematurity was the dominant risk factor, infants born at 25 weeks having 32 times greater odds of death than infants born at 31 weeks. Low birth weight for gestational age also had a dose-response effect: the more growth restricted the infant the greater the risk of mortality; infants below the 3rd centile had eight times greater odds of death than those between the 25th and 75th centiles. Male sex was also a significant risk factor (odds ratio (OR) 1.55, 95% confidence interval (CI) 1.31 to 1.82). Maternal hypertension in pregnancy was protective (OR 0.46, 95% CI 0.36 to 0.50). The predictive model for mortality had an area under the receiver operating characteristic curve of 0.82. CONCLUSIONS: Risk of mortality can be predicted with good accuracy with factors up to the 1 min Apgar score. By using gestation rather than birth weight as the main indicator of maturity, these data confirm that weight for gestational age is an independent risk factor for mortality.

Australasia↗
PubMed2006

Calcaneal ultrasound but not bone turnover predicts fractures in vitamin D deficient frail elderly at high risk of falls.

BACKGROUND: Biochemical markers of bone turnover have been reported to predict fracture risk independent of bone mass in postmenopausal women. We investigated their use in predicting fractures in the frail elderly. METHODS: Cases were 151 low trauma fractures. For each case, a control was selected marched for sex, age, institution type and follow-up period. We measured two bone resorption markers (serum ICTP and serum CTX-I) and two bone formation markers (serum PINP and serum BAP). Quantitative Ultrasound (QUS) was measured in the calcaneus. Fractures were ascertained by x-ray reports. RESULTS: The mean age of subjects was 86.8 years (+/- 5.8 SD) and 86% were female. 76% had hypovitaminosis D (a serum 25 hydroxy vitamin D (25OHD) level < 39 nmol/L) and 81% had BUA < 67.4 dB/MHz (corresponding to a BMD T-score < -2.5). No significant differences in bone turnover markers were detected between fracture cases and their matched controls. In contrast, there was a significant difference between cases and controls for both broadband ultrasound attenuation (BUA) and velocity of sound (VOS) (both P < 0.05). These results remained the same after adjusting for weight, lower leg length and walking aids as well as the higher falls incidence in cases than controls (average 2.7 vs 0.9 falls respectively; P < 0.001) during the follow-up period. CONCLUSION: In the frail elderly with vitamin D deficiency and high falls risk, calcaneal ultrasound but not markers of bone turnover were associated with fractures.

Accidental Falls↗
PubMed2006

Predicting operative delivery.

OBJECTIVE: Unplanned operative delivery (vaginal or abdominal) is associated with maternal anxiety, maternal and neonatal morbidity and increased resource use. We aimed to identify potential predictors for emergency operative delivery. METHODS: This was a prospective observational study of 202 nulliparous women in a tertiary antenatal unit between 36 and 40 weeks' gestation. The assessment included an interview, a vaginal examination for Bishop score (optional), and a translabial ultrasound examination performed with the woman in a supine position and after voiding to determine cervical length, bladder position on Valsalva, and fetal head engagement. Clinical data were obtained from the institutional obstetric database and patient records. RESULTS: In the late third trimester, body mass index (P = 0.016), maternal age at due date (P < 0.0001), history of Cesarean section in first-degree relatives (P = 0.009), Bishop score (P = 0.0004), cervical length (P = 0.001), bladder position on Valsalva (P = 0.003) and head engagement (P < 0.0001) were significantly associated with delivery mode. On multivariate logistic regression analysis, the best model for predicting normal vaginal delivery contained maternal age, history of Cesarean section, Bishop score and bladder position on Valsalva and had excellent ability to discriminate between normal vaginal delivery and operative delivery (c = 0.85). The model with the best ability to discriminate between vaginal delivery and Cesarean section contained the same parameters plus body mass index; this model performed even better (c = 0.87). CONCLUSIONS: Identification of women at increased risk of operative delivery appears feasible. A combination of clinical and ultrasound variables yielded a model that is likely to predict delivery mode accurately in up to 87% of cases. Such a model may become useful as an entry criterion for intervention trials in women at low or very high risk of operative delivery.

Adult↗
PubMed2006

Fetal arrhythmias.

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Arrhythmias, Cardiac↗
PubMed2006

Outcome after preterm delivery of infants antenatally diagnosed with congenital heart disease.

OBJECTIVE: To determine outcome of delivery before 36 weeks gestation in babies diagnosed antenatally with serious congenital heart disease (CHD). STUDY DESIGN: A retrospective database review at 2 tertiary care fetal cardiology centers. Details of neonatal course and outcome were obtained for those antenatally diagnosed with serious CHD who were live born before 36 weeks gestation. RESULTS: Between January 1998 and December 2002, 9918 women were referred for fetal echocardiography. Serious CHD was diagnosed in 1191 fetuses (12%), of which 46 (4%) delivered prematurely. Median gestation was 33 (range 24-35) weeks, and median birth weight 1.56 (0.50-3.59) kg. Extracardiac/karyotypic anomalies occurred in 23 (50%). Twenty-six babies (57%) underwent neonatal surgery: 16 a cardiac procedure, 5 a general surgical procedure, and 5 both. Eight died during or after operation (31%). Two babies underwent interventional heart catheterization; both died. The overall mortality rate was 72%. Extracardiac/karyotypic anomalies increased the relative risk of death by a factor of 1.36. Mean hospital stay for those surviving to initial discharge was 46 (2-137) days. CONCLUSIONS: There is a very high morbidity and mortality rate in this group, particularly for those with extracardiac/karyotypic anomalies. This should be reflected in decisions over elective preterm delivery and when counseling parents.

Abnormalities, Multiple↗
PubMed2005

Prenatal predictors of chronic lung disease in very preterm infants.

OBJECTIVE: To identify prenatal risk factors for chronic lung disease (CLD) at 36 weeks postmenstrual age in very preterm infants. POPULATION: Data were collected prospectively as part of the ongoing audit of the Australian and New Zealand Neonatal Network (ANZNN) of all infants born at less than 32 weeks gestation admitted to all tertiary neonatal intensive care units in Australia and New Zealand. METHODS: Prenatal factors up to 1 minute of age were examined in the subset of infants born at gestational ages 22-31 weeks during 1998-2001, and who survived to 36 weeks postmenstrual age (n = 11 453). Factors that were significantly associated with CLD at 36 weeks were entered into a multivariate logistic regression model. RESULTS: After adjustment, low gestational age was the dominant risk factor, with an approximate doubling of the odds with each week of decreasing gestational age from 31 to less than 25 weeks (trend p<0.0001). Birth weight for gestational age also had a dose-response effect: the lower the birth weight for gestational age, the greater the risk, with infants below the third centile having 5.67 times greater odds of CLD than those between the 25th and 75th centile (trend p<0.0001). There was also a significantly increased risk for male infants (odds ratio 1.51 (95% confidence interval 1.36 to 1.68), p<0.0001). CONCLUSIONS: These population based data show that the prenatal factors low gestational age, low birth weight for gestational age, and male sex significantly predict the development of chronic respiratory insufficiency in very preterm infants and may assist clinical decision about delivery.

Adult↗
PubMed2005

Plastic bronchitis; a serious complication of the Fontan operation.

Plastic bronchitis is characterised by the formation of large bronchial casts, which develop in the tracheobronchial tree and can cause airway obstruction. It has been increasingly encountered in more recent years as a serious complication of the Fontan operation with a reported mortality of up to 50% [Am. J. Respir. Crit. Care Med. 155 (1997) 364]. We report a case of a 4-year-old girl with Fontan circulation who developed plastic bronchitis and was successfully treated.

Administration, Inhalation↗
PubMed2005

Variation in rates of severe retinopathy of prematurity among neonatal intensive care units in the Australian and New Zealand Neonatal Network.

AIM: To analyse variations in rates of severe retinopathy of prematurity (ROP) among neonatal intensive care units (NICUs) in the Australian and New Zealand Neonatal Network (ANZNN), adjusting for sampling variability and for case mix. METHODS: 25 NICUs were included in the study of 2105 infants born at less than 29 weeks in 1998 and 1999, who survived to 36 weeks post-menstrual age and were examined for ROP. The observed NICU rates of severe ROP were adjusted for case mix using logistic regression on gestation, weight for gestational age and sex, and for sampling variability using shrinkage estimates. The corrected rate in the best 20% of NICUs was identified and NICU variations in rates were compared with those in 2000-1. RESULTS: The overall (unadjusted) rate of severe ROP in the NICUs was 9.6% (interquartile range 5.4-12.8%). After adjusting for both case mix and sampling variability there remained significant variation among the NICUs. 20% of NICUs had a rate of severe ROP </=5.9%. Variation in rates among NICUs showed a similar pattern in both time periods. If the overall network rate was reduced to 5.9%, the 20th centile of the adjusted rates, there would be 79 fewer cases in a 2 year period, in contrast with 26 fewer if rates in the two units with excess rates improved to the average. CONCLUSIONS: Considerable variation in rates of severe ROP among NICUs remained after adjustment for case mix and sampling variability. These data will facilitate investigation of potentially better practices associated with a reduced risk of severe ROP.

Australia↗
PubMed2005

Timing of presentation and postnatal outcome of infants suspected of having coarctation of the aorta during fetal life.

OBJECTIVE: To report the timing of presentation and clinical profile of a cohort of fetuses with normal main cardiac connections but fetal echocardiographic signs suggestive of coarctation of the aorta. DESIGN: Retrospective observational study. SETTING: Tertiary fetal and paediatric cardiology centre. PATIENTS: Between 1 January 1998 and 31 December 2002, 174 fetuses were studied, of whom 144 infants were born alive. MAIN OUTCOME MEASURES: Of the 144 liveborn infants, 43 had coarctation of the aorta, four had interruption of the aortic arch, and one was managed as having hypoplastic left heart syndrome. Hemianomalous pulmonary venous drainage was diagnosed in two infants. Three infants with coarctation presented late at 7-13 weeks of age, 6-12 weeks after closure of the arterial duct. Fetuses with cardiac asymmetry had a higher incidence of left superior vena cava than a control group. For fetuses with cardiac asymmetry, the incidence of left superior vena cava and ventricular septal defects was similar in infants who proved to have coarctation postnatally and in those who did not. The 30 day and one year surgical mortality of infants having repair of coarctation of the aorta was two of 41 (4.9%, 95% confidence interval (CI) 0.6 to 16.0). All cause mortality of liveborn infants with any abnormality of the aortic arch was five of 48 (10.4%, 95% CI 3.5 to 22.7) at 30 days and one year, which was heavily influenced by prematurity and extracardiac abnormalities. CONCLUSIONS: Precise diagnosis of coarctation of the aorta during fetal life remains difficult. Coarctation of the aorta may present several weeks after closure of the arterial duct and sequential echocardiography is recommended.

Aortic Coarctation↗
PubMed2005

Fetal dextrocardia: diagnosis and outcome in two tertiary centres.

OBJECTIVE: To evaluate the incidence of fetal dextrocardia, associated cardiac and extracardiac malformations, and outcome. DESIGN: Retrospective echocardiographic study. SETTING: Two tertiary centres for fetal cardiology. PATIENTS: 81 consecutive fetuses with a fetal dextrocardia presenting at Guy's Hospital, London, between 1983 and 2003 and at Hôpital Robert Debré, Paris, between 1988 and 2003. Fetal dextrocardia was defined as a condition in which the major axis of the heart points to the right. RESULTS: The incidence was 0.22%. There were 38 fetuses (47%) with situs solitus (SS), 24 (30%) with situs ambiguus (SA), and 19 (23%) with situs inversus (SI). Structural cardiac malformations were found in 25 cases (66%) of SS, 23 cases (96%) of SA, and 12 cases (63%) of SI. Extracardiac malformations were identified in 12 cases (31%) of SS, in five cases (21%) of SA, and in two cases (10%) of SI. Of the 81 cases of fetal dextrocardia, there were 27 interrupted pregnancies (15 of 24 SA, 10 of 38 SS, and 2 of 19 SI), six intrauterine deaths (3 of 38 SS, 2 of 24 SA, and 1 of 19 SI), and five neonatal deaths (3 of 24 SA, 1 of 19 SI, and 1 of 38 SS). There were 43 survivors (24 of 38 SS, 15 of 19 SI, and 4 of 24 SA). CONCLUSION: The majority of fetuses with dextrocardia referred for fetal echocardiography have associated congenital heart disease. There is a broad spectrum of cardiac malformation and the incidence varies according to the atrial situs. Fetal echocardiography enables detection of complex congenital heart disease so that parents can be appropriately counselled.

Chromosome Disorders↗
PubMed2005

The measurement properties and performance characteristics among older people of TURN180, a test of dynamic postural stability.

OBJECTIVES: To establish the measurement properties of TURN180, a test of dynamic postural stability. DESIGN: One physiotherapist conducted three trials of TURN 180, one of which was also observed by a second therapist. SETTING: A day unit for elderly people accepting both inpatients and outpatients. SUBJECTS: Sixty-six people (mean age 82.45 years), only six (9.1%) of whom could walk without using a walking aid. MAIN MEASUREMENT: The number of steps that a person takes to step around 180 degrees. A step is defined as any attempt on the subject's part to take a step, successful or not. RESULTS: Repeatability is good, intraclass correlation coefficient = 0.828; the minimal detectable change revealed that in order to be considered a real improvement the number of steps the person takes to complete the postintervention TURN180 must be 28-29% fewer than the preintervention count. As long as the protocol is followed carefully, between-observer agreement is good, with differences between two observers rarely exceeding one step. People who had fallen in the previous year took statistically significantly more steps than those who had not done so to complete TURN180. Requesting written as well as oral consent seems to reduce the likelihood of an elderly patient agreeing to participate in a study. CONCLUSION: TURN180 yields repeatable (retest reliable) and valid data about a person's dynamic postural stability, especially the minimal detectable change which allows clinicians to judge whether any change in their patient's performance is real.

Accidental Falls↗
PubMed2004

Condom use in multi-partnered males: importance of HIV and hepatitis B status.

The objective of the research was to determine the demographic, sexual and social risk factors associated with condom use in 7,089 multi-partnered men attending the Sydney Sexual Health Centre. A review of computerized medical records from 1991 to 1999 was carried out. Males with two or more partners in the last three months were divided into three condom use groups: consistent, sometimes and never. Men reporting sex with men (MSM) were more likely to use condoms than men having sex with only women (p=0.001). HIV positive men were more likely to use condoms consistently than those who were negative (p=0.001). In HIV negative non-hepatitis-B carriers, factors independently associated with inconsistent condom use included alcohol consumption, intravenous drug use (odds ratio (OR) 0.6 (95% confidence interval (CI) 0.47-0.77)) and being married (OR 0.2 (95% CI 0.21-0.31)). Factors associated with consistent condom use were MSM (OR 1.8 (95% CI 1.26-2.49)) and having three or more partners in the last 3 months (OR 2.4 (95% CI 2.023-2.83)). In the 508 hepatitis B carriers, consistent condom users were less likely to be married or intravenous drug users (OR 0.4 (95% CI 0.23-0.85)). In the 200 HIV antibody positive men, those with three or more partners were less likely to be consistent condom users than those with two (OR 0.3 (95% CI 0.11-0.82)). The conclusions are that a small number of HIV positive men report unsafe sex with multiple partners. Health promotion activities should be directed at this group.

Adolescent↗
PubMed2004

Condom use in multi-partnered females.

Many women attending sexual health clinics have multiple partners, and determining factors associated with condom use may provide useful information for health promotion strategies. Demographic and sexual data were obtained from computerized records at the Sydney Sexual Health Centre from 1991 to 1999. Females with >2 partners were categorized according to their condom use in the last three months and compared using chi-squared (chi2) tests and logistic regression. Of the 2198 women identified, 22% did not use condoms, 28% reported consistent condom use and 50% inconsistent use. Variables independently associated with failure to use condoms included older age and being in a regular relationship. Women with more partners were more likely to use condoms. Students [odds ratio (OR)=0.7 (95% confidence interval (CI) 0.5-0.9)] and those in employment [OR=0.7 (95% CI 0.5-0.9)] were more likely to use condoms than the unemployed. Focusing health promotion on multi-partnered women who fail to use condoms consistently may help in reducing sexually transmitted infections.

Adolescent↗
PubMed2003

The contribution of work-up or additional views to the accuracy of diagnostic mammography.

This study examines the influence of work-up on the accuracy of diagnostic mammography in symptomatic women. Subjects were sampled from all women consecutively attending a symptomatic breast clinic and aged 25-55 years (240 women shown to have breast cancer and 240 age-matched women shown not to have cancer). Mammography films were prospectively reported by two radiologists independently of each other and in a blinded manner using two phases of film reading: initially only baseline films were read, then mammography was re-read with work-up films. The accuracy of reporting mammography with and without work-up was compared using sensitivity and specificity, likelihood ratios, and receiver operating characteristic (ROC) curves. Reporting the mammogram with work-up (compared to without any work-up films) improved sensitivity (75.3% vs 69.0%, P=0.059) for one radiologist, with a non-significant gain in specificity (84.5% vs 79.4%, P=0.38). For the other radiologist, it resulted in a non-significant decrease in sensitivity (79.5% vs 83.7%, P=0.14) with a significant increase in specificity (85.6% vs 61.9%, P=0.00001). ROC curves for both radiologists showed that reporting mammography with work-up resulted in significant improvement (4.5% for R1, 6.8% for R2) in overall test accuracy. Our findings support the use of work-up mammography in the diagnostic setting.

Adult↗
PubMed2003

Soup kitchen consumer perspectives on the quality and frequency of health service interactions.

OBJECTIVE: Whilst previous research has repeatedly documented premature mortality and high morbidity among seriously disadvantaged and homeless populations, far less is known of the extent and nature of their interactions with health services. DESIGN AND SETTING: This cross-sectional case study describes health service utilization patterns and explores participant-reported difficulties in accessing health care, adhering to prescribed treatment and maintaining continuity of care amongst 100 users of a charity-run soup kitchen in urban Sydney. Participants and results. The study describes a largely welfare-dependent population sample with poor health who are frequent users of the health system (85% had seen a general practitioner in the preceding 6 months). The homeless were more likely to report difficulties accessing health care when needed [odds-ratio 3.15; 95% confidence interval (CI) 1.04-9.62]. One in three respondents reported difficulty adhering to prescribed treatment following their last health care visit. Affordability (P < 0.0001), not understanding instructions (P = 0.007), and not agreeing with advice (P < 0.0001) were the main factors associated with adherence difficulties. One in four failed to return for follow-up visits as advised, largely associated with attitudinal barriers such as a history of not believing problems would be addressed (P = 0.05), not trusting health professionals (P = 0.04), and not knowing where to get help in the past (P = 0.05). CONCLUSION: These results reinforce the important role of free primary care in reducing access barriers for the disadvantaged, but also highlight possible reasons for service interactions being ineffective in a substantial proportion of cases.

Adolescent↗