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R Norton

Publications and source records attributed to R Norton.

At least 19 recordsLinked to original sources

Emergence of further serotypes of multiple drug-resistant Streptococcus pneumoniae in Queensland.

We describe 27 cases of multiple drug-resistant pneumococcal infection in Queensland children (7 cases) and adults (20 cases), between February 1995 and October 1996. Seven patients had invasive disease. Serotypes were those commonly associated with paediatric infections and included types 19F (15 strains), 14 (6), 23F (4), 6A (1) and 19A (1). No rifampicin or vancomycin resistance was encountered. However, pneumococci fully resistant to cotrimoxazole, erythromycin and tetracycline were isolated from 25 of 27 cases (93%). Strains with high level resistance to penicillin and chloramphenicol were also recovered from 16 (59%) and 19 (70%) patients respectively. Twelve of 16 penicillin-resistant isolates showed intermediate resistance to ceftriaxone and two strains were fully resistant to this antibiotic. Clones of types 19F and 14 pneumococci, each with two distinctive resistance patterns, appear to be established in south-east Queensland.

Adult

Regional variation in the incidence of hip fracture in New Zealand.

AIM: To determine the regional incidence of hip fracture among individuals aged 60 years or older in New Zealand. METHODS: New Zealand Health Information Service inpatient morbidity data for the years 1988-92 were examined by area health board region to identify all hip fractures (ICD N820) among individuals aged 60 years or older. RESULTS: Substantial regional variation exists in the incidence of hip fractures among older people in New Zealand. Among both men and women, similar regional variations were observed with the age-standardised rates being consistently highest in the West Coast (790 per 100,000 for women and 360 per 100,000 in men) and lowest in Northland (540 per 100,000 in women and 185 per 100,000 in men). CONCLUSION: These findings have implications for resource allocation, both in terms of targeting prevention initiatives and in providing acute and long term management of hip fracture patients. In addition, they raise questions as to why such variations in hip fracture incidence exist in New Zealand.

Aged

An international study of the exposure of children to traffic.

OBJECTIVES: To examine the extent of international differences in children's exposure to traffic as pedestrians or bicyclists. DESIGN: Children's travel patterns were surveyed using a parent-child administered questionnaire. Children were sampled via primary schools, using a probability cluster sampling design. SETTING: Six cities in five countries: Melbourne and Perth (Australia), Montreal (Canada), Auckland (New Zealand), Umeå (Sweden), and Baltimore (USA). SUBJECTS: Children aged 6 and 9 years. MAIN OUTCOME MEASURES: Modes of travel on the school-home journey, total daily time spent walking, and the average daily number of roads crossed. MAIN FINDINGS: Responses were obtained from the parents of 13423 children. There are distinct patterns of children's travel in the six cities studied. Children's travel in the three Australasian cities, Melbourne, Perth and Auckland, is characterised by high car use, low levels of bicycling, and a steep decline in walking with increasing car ownership. In these cities, over a third of the children sampled spent less than five minutes walking per day. In Montreal, walking and public transport were the most common modes of travel. In Umeå, walking and bicycling predominated, with very low use of motorised transport. In comparison with children in the Australasian and North American cities, children in Umeå spend more time walking, with 87% of children walking for more than five minutes per day. CONCLUSIONS: There are large international differences in the extent to which children walk and cycle. These findings would suggest that differences in 'exposure to risk' may be an important contributor to international differences in pedestrian injury rates. There are also substantial differences in pedestrian exposure to risk by levels of car ownership-differences that may explain socioeconomic differentials in pedestrian injury rates.

Australia

Ethnic differences in blood pressure: findings from the Fletcher Challenge-Auckland University Heart and Health Study.

AIMS: To investigate the determinants of ethnic differences in blood pressure, hypertension and the prevalence of additional risk factors for cardiovascular disease among a New Zealand population. METHODS: Baseline data from the Fletcher Challenge-University of Auckland Heart and Health Study were analysed for ethnic differences in blood pressure, and the likelihood of those with hypertension having other major cardiovascular disease risk factors was estimated. RESULTS: Maori and Pacific Islands participants had mean diastolic blood pressure up to 3 mmHg higher than Europeans, but Pacific Islands people had mean systolic blood pressure 3-4 mmHg lower than Europeans and Maori respectively. After adjustment for age and gender almost 20% of Maori, 16% of Pacific Islands and 11% of European people were classified as hypertensive. Adjustment for body mass index and alcohol consumption almost eliminated ethnic differences in blood pressure, and body mass index was found to be the single most important modifiable determinant of raised blood pressure. Greater proportions of Maori (15%) and Pacific Islands people (14%) with hypertension had multiple additional cardiovascular risk factors compared with Europeans (8%), but similar proportions were on antihypertensive drug treatment. CONCLUSIONS: Efforts to reduce obesity have the potential to significantly reduce raised blood pressure among Maori and Pacific Islands people. Overall cardiovascular risk is more likely to be higher in Maori and Pacific Islands people than in Europeans with hypertension, indicating that greater proportions of Maori and Pacific Islands people with high blood pressure should be receiving treatment.

Adult

Non-specific serum binding to streptavidin in a biotinylated peptide based enzyme immunoassay.

Streptavidin coated microtitre wells can be used to provide attachment to biotinylated peptides, regardless of charge and size, for use in an enzyme immunoassay. Considerable non-specific human serum binding to streptavidin at the recommended concentration was noted. The level of binding varied considerably with serum samples and was unrelated to previous streptococcal disease. Strategies used to reduce this phenomenon included pre-absorption of serum with streptavidin and reducing the streptavidin concentration in the wells. Significant reduction in binding was found with a reduction in streptavidin concentration from the recommended concentration of 0.5 ug/well to 0.01 ug/well.

Adult

The risks of hip fracture in older people from private homes and institutions.

This study aimed to determine whether the incidence of hip fracture is greater among those living in institutions compared with those living in private homes. Over two and a half years of surveillance, 1832 hip fractures were identified, of which 58% were sustained by those living in private homes and 42% by those living in institutions. The risks of hip fracture, unadjusted for age and sex, were 10.5 times greater for those living in institutions compared with those living in private homes. After adjusting for age and sex, these greatly increased risks were maintained, although for both men and women the risks decreased with age, such that at ages over 90 years the risks were not significantly different. Given these findings, hip fracture prevention strategies that focus particularly on individuals within institutions are highly commended.

Aged

Appropriate helicopter transport of urban trauma patients.

OBJECTIVE: Inappropriate use of helicopter transport of trauma patients in urban areas increases costs, risk of injury, and unavailability for appropriate flights. We evaluated the effect of an emergency medical service (EMS) system audit of helicopter trauma scene flights (TSFs) on appropriateness of TSFs. METHODS AND DESIGN: Retrospective cohort. SETTING: Defined urban area with two Level I trauma hospitals. PARTICIPANTS: Consecutive TSFs 2 years before (PRE) and 2 years after (POST) audit. INTERVENTION: EMS system audit established criteria for appropriate TSFs. MAIN RESULTS: The total number of trauma system entries were similar for the two periods: PRE (1989) = 2862; POST (1990 and 1991) = 2787 and 2772. The total number of TSFs decreased after audit (PRE = 122; POST = 50). The proportion of inappropriate (INAPPRO)/total TSFs did not change (62% vs. 66%; chi 2 = 0.04; p = 0.85). There was no difference between appropriate (APPRO) and INAPPRO TSFs for mean vital signs, mechanism of injury, Trauma and Injury Severity Score (TRISS) and Injury Severity Score (ISS), mean length of stay, and proportion of survivors. Scene and transport time intervals were similar. For both PRE and POST periods, 26 APPRO patients (45%) were admitted to non-intensive care unit wards. CONCLUSIONS: An EMS system audit with general awareness of audit criteria decreased the total number of TSFs and hence the number of INAPPRO TSFs in this urban trauma system population. However, the proportion of TSFs that were considered INAPPRO did not change. Criteria for urban TSFs should be based on markers of critical physiologic patient status matched to unique care that the helicopter personnel can provide (e.g., advanced airway management).

Adult

Nonfatal firearm misuse: licence status of perpetrators and legality of the firearms.

The primary aim of this study was to identify the licence status of those involved in incidents of nonfatal firearm-related misuse and to determine the involvement of legal firearms in such incidents. Firearm-related attempted suicides were excluded. The study also sought to identify the types of firearms most likely to be misused. Over a three-month period in early 1994, all nonfatal firearm-related incidents reported in any New Zealand newspaper were identified by a commercial clipping bureau. Data pertaining to the licence status and the legality of the firearm involved in these incidents were obtained from the police who completed a standardized questionnaire under the Official Information Act (1982). Over the study period, 78 incidents yielded information on 97 perpetrators and 100 firearms. Of the 97 perpetrators, 66 per cent were unlicensed, 20 per cent were licensed, the licence status of 8 per cent of the perpetrators was unknown and the remaining 7 per cent were using air guns and therefore a licence was not required. Half of the perpetrators involved in domestic disputes were licensed. Of the 100 firearms, 44 per cent were classified as "legal firearms' and 56 per cent were classified as "illegal firearms'. These findings suggest that strategies aimed at reducing or preventing injury due to firearm misuse must focus on both licensed and unlicensed individuals and both legal and illegal firearms.

Accident Prevention

Incidence of injuries and other health problems in the Auckland Citibank marathon, 1993.

OBJECTIVE: To describe the incidence of injuries and other health problems sustained during participation in a marathon. METHODS: A cohort study was undertaken involving the 1993 Auckland Citibank marathon participants. Demographic data and information on injuries and other health problems sustained during, immediately after, and 7 d following the marathon were obtained from a pre-race questionnaire, the medical aid posts, and a post-race questionnaire. RESULTS: Of the 1219 starters, 916 (75.1%) completed both questionnaires. Seventy five individuals (6.2%) sought assistance at the medical aid posts. During or immediately after the marathon, 283 systemic health problems were reported by 218 respondents (23.8%) and 2671 specific health problems were reported by 846 respondents (92.4%). In the 7 d following the marathon, 1905 specific health problems were reported by 723 respondents (79.2%). The majority of the specific health problems were blisters, stiffness, and pain, predominantly involving the lower limbs. CONCLUSIONS: Although a high proportion of participants experienced health problem during the race, very few of these problems were serious. Many of the entrants were still experiencing problems 7 d after the marathon.

Edema

Child pedestrian injury rates: the importance of "exposure to risk" relating to socioeconomic and ethnic differences, in Auckland, New Zealand.

STUDY OBJECTIVE: To examine how child pedestrian exposure to risk, as measured by the mean number of streets crossed, varies according to indices of material disadvantage and ethnic group. DESIGN: A questionnaire on pedestrian exposure to risk was distributed to children for completion by parents and return to school. Children from 40 schools were selected using a probability cluster design. SETTING: The Auckland region of New Zealand. SUBJECTS: Questionnaires were distributed to 3388 pupils of whom 2873 (85%) completed and returned the questionnaire. RESULTS: The mean number of streets crossed was 2.19 (95% confidence interval 1.82, 2.56) at age 6 years and 2.80 (2.42, 3.17) at age 9 years. The mean number of streets crossed for boys (2.57 (2.15, 2.98)) was similar to that for girls (2.38 (2.05, 2.72)). The mean number of streets crossed by Pacific Island children was 4.87 (4.01, 5.73), more than twice the number crossed by children of predominantly European origin (1.90 (1.65, 2.15)). Children from families without a car crossed an average of 5.34 (4.35, 6.34) streets, compared with 2.90 (2.50, 3.31) streets for children from families with one car, and 1.97 (1.65, 2.29) streets for children from families with two or more cars. CONCLUSION: There are large differences in pedistrian exposure to risk in relation to ethnic group and levels of car ownership. These differences may explain ethnic and socioeconomic differentials in child pedestrian injury rates.

Accidents, Traffic

Fletcher Challenge-University of Auckland Heart & Health Study: design and baseline findings.

AIMS: The aims of this prospective observational study are to determine the relationship of sociodemographic factors, psychological factors and several factors measured in blood, with the risk of coronary heart disease (CHD) in a New Zealand population. METHODS: Participants were recruited from two sources: employees of the Fletcher Challenge Group and individuals listed on the general electoral roll for the Auckland region. Baseline and follow up risk factor data were obtained from a questionnaire, blood samples and a simple physical examination. Outcome data on deaths and hospitalisations due to coronary heart disease will be obtained primarily through linkage of participant identifiers to data collected nationally by the New Zealand Health Information Service. RESULTS: A total of 10,529 individuals agreed to participate (8011 from Fletcher Challenge and 2518 from the electoral roll), representing a response rate of 74%. Within the study population, there was a broad distribution of sociodemographic characteristics including ethnicity-10% of participants were Maori and 5% were of Pacific Islands origin. There was also wide heterogeneity of coronary heart disease risk as judged from the distributions of established risk factors at baseline-5% of participants had evidence of existing coronary heart disease, a quarter were current smokers, a sixth were nondrinkers, almost a half were overweight, a fifth had blood pressure > or = 150/95 mmHg or were receiving antihypertensive treatment and a sixth had cholesterol levels > or = 6.5 mmol/L. CONCLUSIONS: This is the first, large scale prospective observational study of the determinants of coronary heart disease in a New Zealand population. The study participants represent a broad cross section of society, with wide variation in sociodemographic characteristics and coronary heart disease risk. Initial results concerning the relationships of primary interest should be available within 5 years when sufficient coronary heart disease events have been documented to allow reliable analyses.

Adult

Hip fracture incidence among older people in Auckland: a population-based study.

AIM: To determine the incidence of hip fractures among those aged 60 years or older in the Auckland region. METHODS: Demographic data were obtained on all older people hospitalised with a fracture of the femoral neck in Auckland, between 8 July 1991 and 7 February 1994. Incidence rates were calculated using the 1991 census data. RESULTS: An average incidence of 733 hip fractures or 710 individuals sustaining hip fractures each year was observed. Age-adjusted incidence rates were 571.5 per 100,000 for women and 318.2 per 100,000 for men. 97.0% of the hip fractures were sustained by those identified in the records as European, with the rates for Maori and Pacific Island populations 25-50% lower than for Europeans. Among Maori and Pacific Island populations, incidence rates were similar for men and women. Overall, 41.8% of the hip fractures were sustained by those > or = 85 years, with 67.0% sustained by those > or = 80 years. Incidence rates increased with age, with the rates continuing to increase in those > or = 85 years. CONCLUSION: Among Europeans, hip fracture incidence rates in Auckland are similar to those found for other caucasian populations. However, the rates among Maori and Pacific Island populations are among the lowest internationally and are similar for men and women. The increase in incidence rates with age continues in those > or = 85 years.

Aged

Association of angiotensinogen gene T235 variant with increased risk of coronary heart disease.

Several genes, including some encoding components of the renin angiotensin system, are associated with the risk of cardiovascular diseases. There have been reports linking a homozygous deletion allele of the angiotensin converting enzyme (ACE) gene (DD) with an increased risk of myocardial infarction, and some variants of the angiotensinogen gene with an increased risk of hypertension. In a case-control study of a caucasian population from New Zealand, we examined the associations with coronary heart disease (CHD) of ACE DD and of a mis-sense mutation with methionine to threonine aminoacid substitution at codon 235 in the angiotensinogen gene (T235). We studied 422 patients (mean age 62 years, 81% male) with documented CHD (50% with myocardial infarction) and 406 controls without known CHD (frequency-matched to cases by age and sex). Risk factors for CHD were assessed by standard questionnaire, physical examination, and blood tests. Genomic DNA from leucocytes was analysed for various ACE and angiotensinogen alleles. Angiotensinogen T235 homozygotes were at significantly increased risk of CHD generally (odds ratio 1.7, 2 p = 0.008) and of myocardial infarction specifically (1.8, 2 p = 0.009). Adjustment for several risk factors increased the estimate of CHD risk associated with this allele to 2.6 (2 p < 0.001) and the estimate for myocardial infarction risk to 3.4 (2 p < 0.001). By contrast, there was no evidence of a significant increase in the risk of CHD or myocardial infarction among individuals with ACE DD. We conclude that the T235 polymorphism of the angiotensinogen gene is an independent risk factor, which carries an approximately two-fold increased risk of CHD. In this study, however, ACE DD was not associated with any detectable increase in CHD risk.

Alleles

Effect of environmental factors on risk of injury of child pedestrians by motor vehicles: a case-control study.

OBJECTIVE: To identify and assess contribution of environmental risk factors for injury of child pedestrians by motor vehicles. DESIGN: Community based case-control study. Environmental characteristics of sites of child pedestrian injury were compared with the environmental characteristics of selected comparison sites. Each comparison site was the same distance and direction from home of control child as was the injury site from home or relevant case child. Two control sites were selected for each injury site. SETTING: Auckland region of New Zealand. SUBJECTS: Cases were 190 child pedestrians aged < 15 who were killed or hospitalised after collision with a motor vehicle on a public road during two years and two months. Controls were 380 children randomly sampled from population and frequency matched for age and sex. MAIN OUTCOME MEASURE: Traffic volume and speed and level of parking on curbs at injury sites and comparison sites. RESULTS: Risk of injury of child pedestrians was strongly associated with traffic volume: risk of injury at sites with highest traffic volumes was 14 times greater than that at least busy sites (odds ratio 14.30; 95% confidence interval 6.98 to 29.20), and risk increased with increasing traffic volume. High density of curb parking was also associated with increased risk (odds ratio 8.12; 3.32 to 19.90). Risk was increased at sites with mean speeds over 40 km/h (odds ratio 2.68; 1.26 to 5.69), although risk did not increase further with increasing speed. CONCLUSION: Reducing traffic volume in urban areas could significantly reduce rates of child pedestrian injury. Restricting curb parking may also be effective.

Accidents, Traffic

Mycoplasma hominis pneumonia in aboriginal adults.

Mycoplasma hominis (M. hominis) is a well recognized extragenital pathogen. Its role as a pathogen of the respiratory tract, however, remains difficult to determine. Four cases of pneumonia are presented in which M. hominis was isolated from blood, tracheal aspirates or post-mortem lung tissue. All 4 of these isolates were in young Aboriginal adult males. M. hominis is the least fastidious of the human mycoplasmas and grows well on most blood-containing bacteriological media. The recognition and identification of M. hominis is important as it is commonly resistant to erythromycin which would be the drug of choice in most atypical pneumonias. Early recognition and treatment with tetracycline instead may influence outcome.

Adult