Blood pressure and hypertension for Australian Aboriginal and Torres Strait Islander people

BACKGROUND

Reliable, large-scale, population-based data on blood pressure for Australian Aboriginal and Torres Strait Islander populations are limited. This present study aims to describe the blood pressure levels and to explore the clinical risk factors for hypertension among Australian Aboriginal and Torres Strait Islander peoples.

DESIGN

A cross-sectional population survey was conducted in isolated communities in northern and central Australia.

METHODS

Australian Aboriginal people (n = 1088) and Torres Strait Islanders (n = 606) aged 15 years and over were examined between 1993 and 1997. Blood pressure, body mass index, plasma glucose and urinary albumin-creatinine ratio were measured. The association of systolic, diastolic and pulse blood pressure to age was determined and independent associations of hypertension with other clinical variables were tested using logistic regression. Comparisons with results from other Australian data (including AusDiab) were made.

RESULTS

Systolic blood pressure and pulse pressure increased in a linear manner with age but mean diastolic blood pressure leveled off at around 50 years and decreased thereafter, suggestive of arterial stiffening. The age-standardized prevalence of hypertension (blood pressure > or = 140/90 mmHg or medication) for subjects aged 25-54 years was 27%, compared with 9% in non-Indigenous Australians in the Northern Territory and Queensland (AusDiab Survey). Older age, male sex, higher body mass index, albumin-creatinine ratio and diabetes were independently associated with hypertension.

CONCLUSIONS

Elevated blood pressure is a public health concern for indigenous people, which again highlights health differentials in Australia. Early detection and management of high blood pressure should be assigned a high priority in Indigenous communities.

Cement pressurisation in the acetabulum

Cement pressurisation is an important step in total hip arthroplasty that determines the long-term integration at the cement-bone interface. Our aim was to evaluate the performance of a new pressuriser designed by us against the standard existing pressurisers in an in vitro experimental set-up using two parameters: cement penetration and cement pressurisation. A polypropylene cup model was designed to represent the acetabulum. DePuy's T-handle, Exeter and our own plunger type pressuriser were each tested for cement pressurisation in this acetabular model. Cement penetration and pressures were measured. The cement intrusion into the capillaries with the DePuy pressuriser was found to vary between 2 and 8 mm (mean: 5 mm at the pole and 4.6 mm at the rim), with the Exeter pressuriser it varied between 3 and 9 mm (mean: 5.8 mm at the pole and 7.8 mm at the rim) and with the plunger type pressuriser it varied between 4 and 6 mm (mean 5.2 mm at the pole and 4.8 mm at the rim). The peak pressure achieved with the DePuy pressuriser was 60 kPa whereas it was 70 kPa with the plunger type pressuriser. The mean penetration with the plunger type pressuriser was found to be better than the other types. The penetration was found to be more uniform with equal penetration at the rim as well as at the pole.

Validation of the small-punch test as a technique for characterizing the mechanical properties of acrylic bone cement

This paper examines the validity of using the small-punch test technique as a means of quantifying the mechanical properties of acrylic bone cement under different test conditions. The elastic moduli calculated using the small-punch test method were compared with data measured using the international standard for acrylic bone resin, ISO 5833. Conclusions from the study indicate that the small-punch test is a reproducible miniature specimen test method that can be used to characterize the mechanical properties of retrieved acrylic bone cement as used in total joint replacement surgery. Moreover, the test conditions were found to influence the elastic modulus of acrylic bone cement. The test temperature had a greater effect on the elastic behaviour of the bone cement than the test medium.

Diabetes mellitus and serum carotenoids: findings of a population-based study in Queensland, Australia

BACKGROUND

Epidemiologic evidence suggests that serum carotenoids are potent antioxidants and may play a protective role in the development of chronic diseases including cancers, cardiovascular disease, and inflammatory diseases. The role of these antioxidants in the pathogenesis of diabetes mellitus remains unclear.

OBJECTIVE

This study examined data from a cross-sectional survey to investigate the association between serum carotenoids and type 2 diabetes.

DESIGN

Study participants were adults aged > or = 25 y (n = 1597) from 6 randomly selected cities and towns in Queensland, Australia. Study examinations conducted between October and December 2000 included fasting plasma glucose, an oral-glucose-tolerance test, and measurement of the serum concentrations of 5 carotenoid compounds.

RESULTS

Mean 2-h postload plasma glucose and fasting insulin concentrations decreased significantly with increasing quintiles of the 5 serum carotenoids--alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein/zeaxanthin, and lycopene. Geometric mean concentrations for all serum carotenoids decreased (all decreases were significant except that of lycopene) with declining glucose tolerance status. Beta-carotene had the greatest decrease, to geometric means of 0.59, 0.50, and 0.42 micromol/L in persons with normal glucose tolerance, impaired glucose metabolism, and type 2 diabetes, respectively (P < 0.01 for linear trend), after control for potential confounders.

CONCLUSIONS

Serum carotenoids are inversely associated with type 2 diabetes and impaired glucose metabolism. Randomized trials of diets high in carotenoid-rich vegetables and fruit are needed to confirm these results and those from other observational studies. Such evidence would have very important implications for the prevention of diabetes.

Experimental investigation of geologically produced antineutrinos with KamLAND

The detection of electron antineutrinos produced by natural radioactivity in the Earth could yield important geophysical information. The Kamioka liquid scintillator antineutrino detector (KamLAND) has the sensitivity to detect electron antineutrinos produced by the decay of 238U and 232Th within the Earth. Earth composition models suggest that the radiogenic power from these isotope decays is 16 TW, approximately half of the total measured heat dissipation rate from the Earth. Here we present results from a search for geoneutrinos with KamLAND. Assuming a Th/U mass concentration ratio of 3.9, the 90 per cent confidence interval for the total number of geoneutrinos detected is 4.5 to 54.2. This result is consistent with the central value of 19 predicted by geophysical models. Although our present data have limited statistical power, they nevertheless provide by direct means an upper limit (60 TW) for the radiogenic power of U and Th in the Earth, a quantity that is currently poorly constrained.

The Well Person's Health Check: a population screening program in indigenous communities in north Queensland

The National Indigenous Australians Sexual Health Strategy 1996-97 to 1998-99 provided the impetus and resources to assess the health of the large population of Aboriginal and Torres Strait Islander people living in rural and remote communities in northern Queensland, Australia. This paper describes the development, implementation and results of a community based screening program designed to detect and treat sexually transmissible infections and a range of non-communicable conditions and attendant risk factors. The Well Person's Health Check, conducted between March 1998 and December 2000,demonstrated a high prevalence of largely preventable health problems and initiated the development of a sustainable early detection strategy for the region.

Self-reported diabetes and health behaviors in remote indigenous communities in northern queensland, australia

OBJECTIVE

This study examines associations between self-reported diabetes and self-reported smoking, alcohol consumption, fruit consumption, and participation in adequate exercise in remote indigenous communities, using data from the Well Persons' Health Check (WPHC).

RESEARCH DESIGN AND METHODS

The WPHC was a cross-sectional survey of 2,862 indigenous individuals (1,602 Aborigines, 1,074 Torres Strait Islanders, and 186 persons of joint descent) aged > or =15 years. The study was conducted in 26 remote communities in northern Queensland, Australia, between March 1998 and October 2000.

RESULTS

A total of 32% of individuals with self-reported diabetes and 25% of other individuals reported eating enough fruit, according to National Health and Medical Research Council criteria: odds ratio (OR) 1.407 (95% CI 1.108-1.786), P = 0.006. After adjustment for age, sex, and ethnicity, no significant difference could be observed: adjusted OR 1.22 (0.944-1.574), P = 0.128. A total of 58% of participants who reported diabetes and 51% of others reported adequate exercise: OR 0.761 (0.609-0.952), P = 0.018. This difference was not significant after adjustment for age, sex, and ethnicity: adjusted OR 0.896 (0.705-1.14), P = 0.370. A total of 43% of individuals who reported diabetes and 72% of others reported consuming alcohol: OR 0.295 (0.235-0.369), P < 0.001. After adjustment for age, sex, and ethnicity, this difference was still significant: adjusted OR 0.550 (0.428-0.709), P < 0.001. Diabetic drinkers consumed alcohol at harmful levels similar to those of nondiabetic drinkers (P = 0.691). A total of 40% of individuals who reported diabetes and 63% of other persons were tobacco smokers: OR 0.403 (0.322-0.505), P < 0.001. Although this crude difference was attenuated by adjustment for age, sex, and ethnicity, persons with self-reported diabetes were still significantly less likely to smoke tobacco than other participants: adjusted OR 0.666 (0.521-0.852), P = 0.001. Smoking prevalence among the diabetic indigenous participants was more than double that in nondiabetic nonindigenous Australians.

CONCLUSIONS

This study suggests that indigenous individuals with diabetes living in rural and remote communities are not adopting lifestyle changes required for optimal self-management of the disease. This contributes to the large excess of mortality and morbidity experienced by this population.

Food availability, cost disparity and improvement in relation to accessibility and remoteness in Queensland

This study is the first to describe disparity and change in the food supply between metropolitan, rural and remote stores by Accessibility/Remoteness Index of Australia (ARIA) category. A total of 92 stores (97% response rate) within five aggregate ARIA categories participated throughout Queensland in 2000. There was a strong association between ARIA category and the cost of the basket of basic foods, with prices being significantly higher (20% and 31% respectively) in the 'remote' and 'very remote' categories than in the 'highly accessible' category. The association with ARIA was less marked for fruit and vegetables than for other food groups, but not for tobacco and take-away food items. Basic food items were less available in the more remote stores. Over the past two years, relative improvements in food prices have been seen in stores in the 'very remote' category, with observed increases less than the consumer price index (CPI) for food. Some factors which may have contributed to this improvement are discussed.

Obesity, diabetes and associated cardiovascular risk factors among Torres Strait Islander people

OBJECTIVE

To describe the lifestyle-related chronic disease and risk factor prevalence among Torres Strait Islander people of the Torres Strait and Northern Peninsula Area Health Service District and to compare this information with that available for the general Australian population.

METHODS

Voluntary community-based screening for persons aged 15 years and older, including oral glucose tolerance test, anthropometry, health questionnaire, measurement of lipids and lipoprotein levels, blood pressure and urinary albumin to creatinine ratio.

RESULTS

Nine communities participated in screening between 1993 and 1997. Five hundred and ninety-two participants (286 male and 306 female) identified as Torres Strait Islander. There were high prevalences of overweight (30%), obesity (51%), abdominal obesity (70%), diabetes (26%), hypercholesterolaemia (33%), albuminuria (28%), hypertension (32%) and tobacco smoking (45%). Only 8.5% of men and 6.5% of women were free of any cardiovascular risk factors (abdominal obesity, hypercholesterolaemia, hypertension, dyslipidaemia, smoking, diabetes, albuminuria). Comparisons of this information for Torres Strait Islander people with results from the AusDiab survey show rates of obesity three times higher and diabetes six times higher than for other Australians.

CONCLUSIONS

There is a very high prevalence of preventable chronic disease and associated risk factors among Torres Strait Islander people of the Torres Strait and Northern Peninsula Area.

IMPLICATIONS

Effective interventions to prevent and manage obesity, diabetes and associated cardiovascular risk factors are essential if the health of the Torres Strait Islander people is to improve. Such interventions could inform initiatives to stem the burgeoning epidemic of obesity and diabetes among all Australians.

Potential health and environmental issues of mercury-contaminated amalgamators

BACKGROUND

Dental amalgamators may become contaminated internally with metallic mercury. This contamination may result from mercury leakage from capsules during trituration or from the long-term accrual from microscopic exterior contaminants that result from the industrial assembly process. The potential health risk to dental personnel from this contamination is unknown.

METHODS

The authors assessed used amalgamators from the federal service inventory for the amounts of mercury vapor levels, as well as the visual presence of mercury contamination. They evaluated these amalgamators for potential mercury vapor health risk, using established National Institute for Occupational Safety and Health methods and American Conference of Governmental Industrial Hygienists standards.

RESULTS

Ten of the 11 amalgamators assessed had measurable mercury vapor levels. Four amalgamators were found to have internal static mercury vapor levels above Occupational Safety and Health Administration ceiling limit thresholds. During a simulated worst-case clinical use protocol, the authors found that no amalgamators produced mercury vapor in the breathing space of dental personnel that exceeded established time-weighted federal mercury vapor limits.

CONCLUSIONS

Amalgamators may be contaminated internally with metallic mercury. Although the authors detected mercury vapor from these units during aggressive, simulated clinical use, dilution factors combined with room air exchange were found to keep health risks below established federal safety thresholds.

CLINICAL IMPLICATIONS

Dental personnel should be aware that amalgamators may be contaminated with mercury and produce minute amounts of mercury vapor. These contaminated amalgamators may require disposal as environmentally hazardous waste.

Gurus in the garage

Before the days of the Internet, it was primarily venture capitalists who coached young entrepreneurs in Silicon Valley. Today, because of the phenomenal number of new companies, venture capitalists are just too busy. The largest firms still take on a few carefully selected, highly promising zero-stage start-ups, but they simply can't spend the time on ones that aren't going to grow huge quickly. To fill the void, a new breed of adviser has stepped in to coach entrepreneurs. Called mentor capitalists, they help entrepreneurs with everything from recruiting top talent to attracting their first million in seed money. The mentor capitalists in Silicon Valley are cashed-out, highly successful business architects who no longer want to start businesses but who love the thrill of the entrepreneurial game. They spend hours and hours with first-time entrepreneurs, guiding them as they create and refine a business model, test their ideas in the marketplace, build business processes, raise money, and find talent. The authors of this article found through dozens of extensive interviews with entrepreneurs and their coaches that mentor capitalists play many roles: sculptor, psychologist, diplomat, kingmaker, talent magnet, process engineer, and rainmaker. In exchange for small equity stakes, the mentor capitalists wear these different hats, doling out expertise just in time, as situations arise, and in doses appropriate to the situation. Mentor capitalists seed Silicon Valley with expertise and knowledge, augmenting or even substituting for classes in entrepreneurship at local universities. But, as the authors note, the role of the mentor capitalist is essential to any start-up, anywhere.

Albuminuria in Australian Aboriginal people: prevalence and associations with components of the metabolic syndrome

AIMS/HYPOTHESIS

To examine the prevalence and associations with the metabolic syndrome of albuminuria among Australian Aboriginal people.

METHODS

Early-morning urine specimens were collected as part of community-based risk factor surveys assessing the prevalence of diabetes and cardiovascular disease in eight remote communities, with a sample size of 1,075 people. Microalbuminuria was defined as urinary albumin : creatinine ratio 3.4-33.9 mg/mmol, macroalbuminuria as albumin: creatinine ratio equal to or greater than 34 mg/mmol.

RESULTS

There were high prevalences of microalbuminuria (men 22.2 %, women 26.9 %) and of macroalbuminuria (men 10.4%, women 13.5%). There were highly statistically significant linear associations of microalbuminuria and macroalbuminuria with increasing number of coexisting components of the metabolic syndrome (hypertension, glucose intolerance, dyslipidaemia, insulin resistance, abdominal obesity): among people with zero, one, two and three to five of these conditions, respectively, prevalence of microalbuminuria was 16%, 20%, 36% and 32% (p < 0.001); prevalence of macroalbuminuria was 2%, 6%, 12% and 32% (p < 0.001). There were independent associations of microalbuminuria with hypertension (odds ratio, 95% confidence interval = 2.36, 1.63-3.42) and diabetes (2.10, 1.28-3.45): macroalbuminuria was independently associated with hypertension (6.39, 3.93-10.4), diabetes (3.49, 1.93-6.28) and abdominal obesity (4.56, 2.40-8.64) and had a weaker association with insulin resistance (1.99, 1.12-3.54). Dyslipidaemia and impaired glucose tolerance were neither independently associated with microalbuminuria or macroalbuminuria, nor was insulin resistance or abdominal obesity independently associated with microalbuminuria.

CONCLUSION/INTERPRETATION

There was a strong clustering of albuminuria with components of the metabolic syndrome. Diabetes, hypertension and abdominal obesity are major contributors to high rates of albuminuria among Australian Aboriginal people.

Cautery-assisted palatal stiffening operation for the treatment of obstructive sleep apnea syndrome

Cautery-assisted palatal stiffening operation (CAPSO) is a recently developed single office-based procedure performed with local anesthesia for the treatment of palatal snoring. A midline strip of soft palate mucosa is removed, and the wound is allowed to heal by secondary intention. The flaccid palate is stiffened, and palatal snoring ceases. This prospective study evaluated the ability of CAPSO to treat obstructive sleep apnea syndrome (OSAS). Twenty-five consecutive patients with OSAS underwent CAPSO. Responders were defined as patients who had a reduction in apnea-hypopnea index (AHI) of 50% or more and an AHI of 10 or less after surgery. By these strict criteria, 40% of patients were considered to have responded to CAPSO. Mean AHI improved from 25.1+/-12.9 to 16.6+/-15.0 (P = 0.010). The Epworth Sleepiness Scale, a subjective measure of daytime sleepiness, improved from 12.7+/-5.6 to 8.8+/-4.6 (P<0.001). These results indicate that CAPSO is as effective as other palatal surgeries in the management of OSAS.