High prevalence of vasectomy in New Zealand.

The aim of this study was to examine the prevalence of vasectomy and associated factors in New Zealand, based on interviews with men. Participants were randomly selected from European men, aged between 40 and 74 years, on the general electoral roll. Telephone interviews were completed with 1225 men between 1997 and 1999. Overall, the prevalence of vasectomy was 44% (95% CI, 37-52%), adjusted to the age distribution of all New Zealand men aged 40-74 years. The prevalence ranged from 57% of men aged 40-49 years to 15% of those aged 70-74 years. Catholic men had a significantly lower odds of vasectomy, and there was a trend in increasing odds of vasectomy with increasing number of marriages and level of education of the wife. The results confirm a very high prevalence of vasectomy among New Zealand men. Comparison with earlier surveys based on interviews of women showed an increasing prevalence of vasectomy in each birth cohort from the 1920s to the 1950s. Vasectomy has been popular with men across all socioeconomic groups. New Zealand is an ideal country in which to study consequences of vasectomy.     

Attendance for general practitioner asthma care by children with moderate to severe asthma in Auckland, New Zealand

Attendance for general practitioner (GP) care of childhood asthma varies widely in New Zealand (NZ). There is little current research to account for the variations, although groups such as Māori and Pacific peoples have traditionally faced barriers to accessing GP care. This paper aims to describe and account for attendance levels for GP asthma care among 6-9 year-olds with moderate to severe asthma in Auckland, NZ. During 2002, randomly selected schools identified all 6-9 year-olds with possible breathing problems. Completion of a questionnaire by each parent/guardian indicated which children had moderate to severe asthma, and what characteristics influenced their access to GP asthma care. A multilevel, negative binomial regression model (NBRM) was fitted to account for the number of reported GP visits for asthma, with adjustment for clustering within schools. Twenty-six schools (89.7 percent) identified 931 children with possible breathing problems. Useable questionnaires were returned to schools by 455 children (48.9 percent). Results indicated 209 children with moderate to severe asthma, almost one in every three reportedly making 5 or more GP visits for asthma in the previous year. Māori, Pacific and Asian children were disproportionately represented among these 'high attendees'. Low attendees (0-2 visits) were mainly NZ Europeans. The NBRM (n=155) showed that expected visits were increased by perceived need, ill-health, asthma severity and, in particular, Māori and Pacific child ethnicity. It may be that Māori and Pacific children no longer face significant barriers to accessing GP asthma care. However, more likely is that barriers apply only to accessing routine, preventative care, leading to poor asthma control, exacerbations requiring acute care, and paradoxically an increase in GP visits. That barriers may increase total numbers of visits challenges the assumption, for all health systems, that access can be defined in terms of barriers that must be overcome to obtain health care.     

Increasing hospitalizations for serious skin infections in New Zealand children, 1990-2007

The incidence of serious skin infections in New Zealand children is significantly higher than in comparative countries. This study aimed to describe the epidemiology of these infections and identify changes in disease distribution over time. Discharge data were analysed for all children admitted to a New Zealand public hospital with a serious skin infection during the period 1990-2007. Patient and admission variables were compared between 1990-1999 and 2000-2007. The incidence of serious skin infections almost doubled from 298·0/100,000 in 1990 to 547·3/100,000 in 2007. The highest rates were observed in boys, preschool-aged children, Māori and Pacific children, those living in deprived neighbourhoods, urban areas and northern regions. Over time there were disproportionate increases in infection rates in Māori and Pacific children and children from highly deprived areas. Serious skin infections are an increasing problem for New Zealand children. Worsening ethnic and socioeconomic health inequalities may be contributing to increasing rates.     

A case-control study of risk factors for asthma in New Zealand children

OBJECTIVE: As in other English-speaking countries, asthma is a major and increasing health problem in New Zealand. This study examined the risk factors for asthma in children aged 7-9. METHODS: Cases and controls were randomly selected from participants in the Wellington arm of the International Study of Asthma and Allergies in Childhood (ISAAC). Cases were children with a previous diagnosis of asthma and current medication use (n=233), and controls were children with no history of wheezing and no diagnosis of asthma (n=241). RESULTS: After controlling for confounders, factors significantly associated with asthma were maternal (OR=3.36, 95% CI 1.88-5.99) and paternal asthma (OR-2.67, 95% CI 1.42-5.02), and male sex (OR=1.81, 95% CI 1.17-2.81). Children from social classes 5 and 6 or with unemployed parents (OR=2.32, 95% CI 1.22-4.44) were significantly more likely to have asthma than children in social classes 1 and 2. There was no significant association between having polio vaccination (OR=2.48, 95% CI 0.83-7.41), hepatitis B vaccination (OR=0.66, 95% CI 0.42-1.04) or measles/mumps/rubella vaccination (OR=1.43, 95% CI 0.85-2.41) and asthma. CONCLUSIONS: This study has confirmed the associations of family history and lower socio-economic status with current asthma in 7-9 year old children. The role of vaccinations requires further research.     

Domestic nitrogen oxide exposure, urinary nitrate, and asthma prevalence in preschool children.

A South Australian preschool study carried out in 1993 showed that the prevalence of respiratory symptoms was significantly associated with use of unflued gas appliances for cooking and heating. The authors sought to determine an association between domestic exposure to nitrogen dioxide and the excretion of total urinary nitrate and nitrite, and their association with asthma prevalence. The results indicated that the geometric mean concentrations of nitrogen dioxide were much higher in homes that had natural gas appliance(s) and other types of appliances (i.e., electric and solid fuel). Higher levels of nitrogen dioxide were found in homes of suburban areas with higher prevalence of asthma and respiratory symptoms. Nitrogen dioxide levels were lower in the summer, and there was a higher level in kitchens than in bedrooms. Urinary nitrate excretion was evaluated in 1,335 preschool children from the same sampling areas. No association existed between nitrogen dioxide levels and urinary nitrates, nor was there a relationship between urinary nitrates and asthma prevalence. These findings confirm that there is a positive association between nitrogen dioxide exposure from gas appliances and the prevalence of respiratory symptoms, but urinary nitrate is not a useful biomarker of exposure at these levels.     

Modeling the costs of hospital-acquired infections in New Zealand.

OBJECTIVE: To model the economic costs of hospital-acquired infections (HAIs) in New Zealand, by type of HAI. DESIGN: Monte Carlo simulation model. SETTING: Auckland District Health Board Hospitals (DHBH), the largest publicly funded hospital group in New Zealand supplying secondary and tertiary services. Costs are also estimated for predicted HAIs in admissions to all hospitals in New Zealand. PATIENTS: All adults admitted to general medical and general surgical services. METHOD: Data on the number of cases of HAI were combined with data on the estimated prolongation of hospital stay due to HAI to produce an estimate of the number of bed days attributable to HAI. A cost per bed day value was applied to provide an estimate of the economic cost. Costs were estimated for predicted infections of the urinary tract, surgical wounds, the lower and upper respiratory tracts, the bloodstream, and other sites, and for cases of multiple sites of infection. Sensitivity analyses were undertaken for input variables. RESULTS: The estimated costs of predicted HAIs in medical and surgical admissions to Auckland DHBH were dollar 10.12 (US dollar 4.56) million and dollar 8.64 (US dollar 3.90) million, respectively. They were dollar 51.35 (US dollar 23.16) million and dollar 85.26 (US dollar 38.47) million, respectively, for medical and surgical admissions to all hospitals in New Zealand. CONCLUSIONS: The method used produces results that are less precise than those of a specifically designed study using primary data collection, but has been applied at a lower cost The estimated cost of HAIs is substantial but only a proportion of infections can be avoided. Further work is required to identify the most cost-effective strategies for the prevention of HAI.     

Escherichia coli in gastroenteritis of children in Auckland, New Zealand.

A study of stool Escherichia coli in 60 children with gastroenteritis and 18 control children was carried out in Auckland, New Zealand in 1977. Toxigenic strains, heat labile and heat stable, predominated in the stools of only three children, all of whom had concomitant rotavirus. Classical enteropathogenic E. coli (EPEC) were found in patients and controls. Only one patient had many EPEC in the stool (086.H2), they were variably toxigenic and rotavirus was also present. No toxigenic serotype was isolated. Two potential pathogens were sometimes found. Overall there was no evidence for a substantial causative role for disease producing E. coli in these children.     

A seroepidemiological study of the prevalence of hepatitis B infections in a hyperendemic New Zealand community

The prevalence of hepatitis B surface antigen (HBsAg) and its antibody (anti-HBs) were studied in 93% of the population of the New Zealand township of Kawerau. Sera were collected from 7901 subjects over six months old, and 3318 (42%) had markers of hepatitis B virus (HBV) infections. Five hundred and nineteen (6.6%) were positive for HBsAg and 485 (96.4%) of 503 retested were confirmed as chronic carriers. HBsAg prevalence was 5.4% in the 0-4 years age group but only 1 of 66 children under one year old was positive suggesting that later cross infection, rather than perinatal transmission was the major factor responsible for the high pre-school carrier rate. Total HBV marker prevalence increased dramatically in early school years and peak marker prevalence was 67.7% in the 15-19 year age group. Prevalence of HBsAg was more than four times higher in non-europeans than in Europeans (Caucasians). Other factors significantly associated with hepatitis B virus marker prevalence in children were: number of years spent in Kawerau, which was associated with anti-HBs prevalence; and size of household, which was associated with HBsAg prevalence. Number of siblings was not a significant risk factor over and above the effect of size of household. Factors associated with marker prevalence in adults were: number of years spent in Kawerau, which was associated with anti-HBs; birth in the Northern half of the North Island, which was associated with both HBsAg and anti-HBs; size of household, which was more strongly associated with HBsAg prevalence; and amateur tattoos, which were associated with anti-HBs prevalence but not with HBsAg prevalence.     

Climate, traffic-related air pollutants, and asthma prevalence in middle-school children in taiwan

This study compared the prevalence of asthma with climate and air pollutant data to determine the relationship between asthma prevalence and these factors. We conducted a nationwide survey of respiratory illness and symptoms in middle-school students in Taiwan. Lifetime prevalences of physician-diagnosed asthma and of typical symptoms of asthma were compared to air monitoring station data for temperature, relative humidity, sulfur dioxide, nitrogen oxides, ozone, carbon monoxide, and particulate matter with aerodynamic diameter [less than/equal to] 10 microm (PM(10)). A total of 331,686 nonsmoking children attended schools located within 2 km of 55 stations. Asthma prevalence rates adjusted for age, history of atopic eczema, and parental education were associated with nonsummer (June-August) temperature, winter (January-March) humidity, and traffic-related air pollution, especially carbon monoxide and nitrogen oxides, for both girls and boys. Nonsummer temperature, winter humidity, and traffic-related air pollution, especially carbon monoxide and nitrogen oxides, were positively associated with the prevalence of asthma in middle-school students in Taiwan.     

Recent trends in upper respiratory infections, ear infections and asthma among young Canadian children

Upper respiratory (nose and throat) infections, ear infections and asthma are common among young children. This article uses data from the National Longitudinal Survey of Children and Youth (NLSCY) to trace trends in the prevalence of these conditions among young children in Canada from 1994/1995 to 2008/2009. Gender, age and regional differences in the occurrence of these conditions are examined, and possible links with exposure to cigarette smoke are considered. The prevalence of upper respiratory infections among children aged 2 to 3 remained constant or declined in most regions of Canada between 1994/1995 and 2008/2009, but rose significantly in Quebec. Ear infections declined significantly in all regions. The prevalence of asthma among children aged 2 to 7 rose steadily until 2000/2001 and then declined. A wide range of environmental factors, including reduced exposure to cigarette smoke, may have contributed to these trends.     

Family influences, acculturation, and the prevalence of tobacco smoking among Asian youth in New Zealand: findings from a national survey

The associations among family factors, acculturation, and the risk of regular smoking among Asian youth were investigated in a nationally representative survey in New Zealand. The strong relationships between protective family factors and lower risks of smoking were not attenuated in the presence of indicators suggestive of acculturation.     

The prevalence of asthma in children of elementary school age in Western New York

To determine the prevalence of caregiver-reported asthma in children 4 to 13 years old in metropolitan western New York State, surveys were conducted during 1997–1999 in the Buffalo, Niagara Falls, Iroquois, and Gowanda school systems. Questionaires (3,889) were sent to the homes of elementary school children in nine schools in western New York. The caregivers were asked to complete a 13-item questionnaire for the child. Of the questionnaires, 60.5% (2,353/3,889) were completed. Of all children, 18% had physician-diagnosed asthma. Of children diagnosed with asthma, 86% were taking medication. Symptoms were consistent with suspected undiagnosed asthma for 13% of the children. Buffalo had the highest rate of diagnosed asthma (20%) for the age group. Gowanda had a prevalence of 18%, Iroquois 16%, and Niagara Falls 15%. Variations were observed in asthma prevalence rates among different racial/ ethnic groups. In general, boys had a significantly (P=.001) increased odds of being asthmatic compared with girls. Overall, African-Americans and Hispanic/Latino children had significantly (P=.012 andP=.005, respectively) higher asthma prevalence rates, two to five times those of their Caucasian peers. In Gowanda, the prevalence of diagnosed asthma among Native American children was 23%, compared to 15% among Caucasian children. Of diagnosed Native American children, 71% were female. In Gowanda, a significant association (P=.007) of asthma among children in split-grade classes was observed compared to nonsplit grades. Of Native American children in split grades, 60% were diagnosed asthmatics. These observations reveal a high prevalence of asthma in the age group of 4 to 13 year olds in western New York. Local variations in potential triggers of asthma need to be considered when advising asthmatics. The results suggest that some grades have a disproportionate amount of children with asthma. The implications of asthma for children's early education need to be examined further. This project was supported in part by a grant from Kaleida Health Foundations.     

Potroom asthma: New Zealand experience and follow-up

Occupational asthma related to work in potlines in an aluminum smelter has been diagnosed on clinical criteria in 57 workers. About half were regular tobacco smokers but atopy was uncommon. There was a wide range in the time for which each had been employed prior to development of symptoms, but the average was about 20 months. Thirty-four showed nonspecific bronchial hyperreactivity to methacholine. At annual reviews over a period of 5 years following transfer to other work at the smelter, the majority improved in symptoms in 1-2 years and bronchial hyperreactivity returned to normal. However, over the subsequent 3 years, deterioration, not limited to tobacco smokers or atopic subjects, has occurred in some subjects.     

Recent changes in the prevalence of asthma in children

Over the past decennia, the prevalence of asthma in children has increased worldwide. The increase in prevalence of asthma symptoms has been estimated at around 5% per year in various countries. Possible explanations are an increasing level of awareness in doctors and patients and changes in lifestyle in affluent societies. Recent data suggest that this trend has been levelling off. Recent data also suggest that in The Netherlands the situation has been stabilizing, indeed there has been a decrease in the prevalence of asthma in children. The next few years will reveal whether this situation will remain stable or the trend will show a further decrease.     

Family size, day-care attendance, and breastfeeding in relation to the incidence of childhood asthma

A hypothesis has been suggested stating that children exposed early to infections are less likely to develop atopy or asthma. The authors investigated the relation between risk of childhood asthma and number of siblings as well as day-care attendance, as factors possibly increasing the likelihood of early infections, and breastfeeding as a factor reducing them. A case-control study was carried out in Montréal, Canada, between 1988 and 1995 that included 457 children diagnosed with asthma at 3--4 years of age and 457 healthy controls. Cases followed for 6 years were later classified as persistent or transient by the symptoms and use of medication after diagnosis. Among cases diagnosed at 3--4 years of age, the adjusted odds ratio for asthma was 0.54 (95% confidence interval (CI): 0.36, 0.80) for one sibling and 0.49 (95% CI: 0.30, 0.81) for two or more. The adjusted odds ratio for day-care attendance before 1 year of age was 0.59 (95% CI: 0.40, 0.87). Results were similar with persistent cases. Among transient cases (who possibly had an infection with wheezing at 3--4 years of age), day-care attendance and a short duration of breastfeeding resulted in increased risk. The results support the hypothesis that opportunity for early infections reduces the risk of asthma.     

High prevalence,persistent hazardous drinking among New Zealand tertiary students

AIMS: To determine the prevalence of hazardous drinking and alcohol-related negative consequences in New Zealand tertiary students, and to identify predictors of hazardous drinking across a 6-month period. METHODS: A total of 1480 tertiary students living in halls of residence was surveyed at the start of the academic year, and a subsample of 967 students was followed up 6 months later. Questionnaire items included quantity and frequency of drinking, alcohol-related problems, use of other substances, and the Alcohol Use Disorders Identification Test (AUDIT). Drinking at follow-up was modelled using demographic characteristics, mental well-being, other substance use, alcohol-related problems, and hall drinking norms, measured at baseline. RESULTS: Among drinkers, mean (+/- SD) weekly consumption was 243 +/- 241 and 135 +/- 157 g of ethanol for males and females respectively. The majority of male (60.0%) and female (58.2%) drinkers typically consumed more than national safe drinking guidelines. Mean (+/- SD) AUDIT scores were 10.9 +/- 7.6 for males and 7.6 +/- 5.9 for females. After controlling for AUDIT scores at baseline, increased AUDIT scores at follow-up were higher with lower age, Maori ethnicity, smoking, cannabis use, high levels of alcohol-related negative consequences, and higher levels of drinking in the student's hall of residence. CONCLUSIONS: Hazardous drinking is widespread and persistent among students living in the halls of residence. There is a need for university alcohol policies and intervention approaches among New Zealand tertiary students.     

Prevalence of adult asthma symptoms in relation to climate in New Zealand.

We conducted an ecological study linking prevalence of adult asthma symptoms with climate in the 93 New Zealand general electorates. For each electorate, the 12-month period prevalence of self-reported asthma symptoms was determined using a random sample of adults aged 20-44 on the 1991 New Zealand electoral roll. Long-term average climate was estimated using a national climate database and a geographic information system. Asthma prevalence was calculated within quartiles of the exposure variables. Independent effects of climate variables were assessed using linear regression models, with adjustment for confounding by climate, social deprivation, and geographic variables. There was a statistically significant association between asthma prevalence and mean temperature, with the lowest quartile of mean temperature having an approximately 2% lower asthma prevalence. After adjusting for confounding, there was a monotonic increase in asthma prevalence within quartiles of temperature. The results of this study are in agreement with other research suggesting a lower prevalence of asthma at low temperatures. Although on short (day-to-day) time scales, low temperatures may have a direct effect resulting in acute exacerbations of asthma symptoms, warmer average temperatures are associated with increased asthma prevalence. The reasons for this are unclear, although it is possible that on longer term (annual) time scales, higher temperatures are associated with higher levels of allergen exposure.     

Age-period-cohort analysis of asthma prevalence among school children

Prevalence of age-dependent diseases such as asthma is confounded not only by aging effects but also by cohort and period effects. Age-period-cohort (APC) analysis is commonly performed to isolate the effects of these three factors from two-way tables of prevalence by age and birth cohort. However, APC analysis suffers from technical difficulties such as non-identifiability problems. We isolated the effects of these three factors in a step-by-step manner by analyzing Japan’s school health data collected from 1984 to 2004 focusing on asthma prevalence among school children aged 6–17 years consisting of 30 birth cohorts (entering classes). We verified the accuracy of our method showing high agreement of the observed age-, period- and cohort-specific data and the data predicted by our method. The aging effects were found to follow cubic equations whose multinomial coefficients were determined by an optimization technique. The obtained aging effect curves of age-specific asthma prevalence showed that boys reach the peak prevalence at 13 and girls at 14, declining markedly afterward. The cohort effects, defined as the arithmetic asthma prevalence means for ages 6–17 years, showed consistent upward trends for the 30 birth cohorts born in 1968–97 for both sexes. The period effects showed a consistent decline since 1984 but abruptly increased in 1999 and then declined again. We were not able to identify the exact cause of the increase in 1999, therefore, this should be examined in the future studies. Because the cohort effects show no sign of leveling off yet, asthma prevalence will likely increase in the foreseeable future.     

The prevalence and estimates of the cumulative incidence of hospital-acquired infections among patients admitted to Auckland District Health Board Hospitals in New Zealand.

OBJECTIVES: To report the pooled results of seven prevalence surveys of hospital-acquired infections conducted between November 1996 and November 1999, and to use the data to predict the cumulative incidence of hospital-acquired infections in the same patient group. DESIGN: The summary and modeling of data gathered from the routine surveillance of the point prevalence of hospital-acquired infections. SETTING: Auckland District Health Board Hospitals (Auckland DHBH), the largest publicly funded hospital group in New Zealand supplying secondary and tertiary services. PATIENTS: All inpatients. METHOD: Point-prevalence surveys were conducted including all patients in Auckland DHBH. Standard definitions of hospital-acquired infection were used. The data from the seven surveys were pooled and used in a modeling exercise to predict the cumulative incidence of hospital-acquired infection. An existing method for the conversion of prevalence to cumulative incidence was applied. Results are presented for all patients and stratified by clinical service and site of hospital-acquired infection. RESULTS: The underlying patterns of hospital-acquired infection by site and service were stable during the seven time periods. The prevalence rate for all patients was 9.5%, with 553 patients identified with one or more hospital-acquired infections from a population of 5,819. The predicted cumulative incidence for all patients was 6.33% (95% confidence interval, 6.20% to 6.46%). CONCLUSIONS: The prevalence and the predicted cumulative incidence are similar to rates reported in the international literature. The validity of the predicted cumulative incidence derived here is not known. If it were accurate, then the application of this method would represent a cost-effective alternative to incidence studies.