Body mass index and waist circumference as predictors of all-cause mortality in an Aboriginal Australian community.

Although elevated body mass index (BMI) and waist circumference (WC) have been identified as risk factors for mortality, data from the Australian Aboriginal communities are scarce. This study examined the associations of BMI and WC with all-cause mortality in an Australian Aboriginal community. A total of 934 Aboriginal adults, aged 18-76 years, who participated in a community-wide screening programme in Australia's Northern Territory from 1992 to 1998, were followed-up prospectively for up to 18 years for death outcomes. The hazard ratios for mortality were estimated by baseline BMI and WC. Age, sex, smoking and alcohol consumption status were adjusted for in multivariable analysis. In 14,750 person-years of follow-up, 216 deaths were recorded. For each standard deviation increase in BMI, the risk of all-cause death decreased by 9% (95% CI: 0.80-1.05); whereas for each SD increase in WC, the risk of all-cause mortality increased by 17% (95% CI: 1.03-1.33). The risk of mortality was lower in the 3rd BMI tertile compared to the 1st tertile for mortality after adjusting for WC, age, sex, smoking and alcohol consumption. Risk of death was higher in WC tertile 3 compared to tertile 1 after adjusting for BMI, age, sex, smoking and alcohol consumption. The risk of all-cause mortality among participants increased with higher WC, while participants with relatively higher BMI had a lower mortality risk. WC had stronger association with mortality than did BMI. The results indicate the importance of assessing WC measures in studies conducted in Aboriginal Australia.

Adegbija O ，Hoy WE ，Dong B ，Wang Z ... -  《Obesity Research & Clinical Practice》

Waist circumference values equivalent to body mass index points for predicting absolute cardiovascular disease risks among adults in an Aboriginal community: a prospective cohort study.

There have been suggestions that currently recommended waist circumference (WC) cut-off points for Australians of European origin may not be applicable to Aboriginal people who have different body habitus profiles. We aimed to generate equivalent WC values that correspond to body mass index (BMI) points for identifying absolute cardiovascular disease (CVD) risks. Prospective cohort study. An Aboriginal community in Australia's Northern Territory. From 1992 to 1998, 920 adults without CVD, with age, WC and BMI measurements were followed-up for up to 20 years. Incident CVD, coronary artery disease (CAD) and heart failure (HF) events during the follow-up period ascertained from hospitalisation data. We generated WC values with 10-year absolute risks equivalent for the development of CVD as BMI values (20-34 kg/m(2)) using the Weibull accelerated time-failure model. There were 211 incident cases of CVD over 13,669 person-years of follow-up. At the average age of 35 years, WC values with absolute CVD, CAD and HF risks equivalent to BMI of 25 kg/m(2) were 91.5, 91.8 and 91.7 cm, respectively, for males, and corresponding WC values were 92.5, 92.7 and 93 cm for females. WC values with equal absolute CVD, CAD and HF risks to BMI of 30 kg/m(2) were 101.7, 103.1 and 102.6 cm, respectively, for males, and corresponding values were 99.2, 101.6 and 101.5 cm for females. Association between WC and CVD did not depend on gender (p=0.54). WC ranging from 91 to 93 cm was equivalent to BMI 25 kg/m(2) for overweight, and 99 to 103 cm was equivalent to BMI of 30 kg/m(2) for obesity in terms of predicting 10-year absolute CVD risk. Replicating the absolute risk method in other Aboriginal communities will further validate the WC values generated for future development of WC cut-off points for Aboriginal people.

Adegbija O ，Hoy WE ，Wang Z 《BMJ Open》

Comparison of Two Modern Survival Prediction Tools, SORG-MLA and METSSS, in Patients With Symptomatic Long-bone Metastases Who Underwent Local Treatment With Surgery Followed by Radiotherapy and With Radiotherapy Alone.

Survival estimation for patients with symptomatic skeletal metastases ideally should be made before a type of local treatment has already been determined. Currently available survival prediction tools, however, were generated using data from patients treated either operatively or with local radiation alone, raising concerns about whether they would generalize well to all patients presenting for assessment. The Skeletal Oncology Research Group machine-learning algorithm (SORG-MLA), trained with institution-based data of surgically treated patients, and the Metastases location, Elderly, Tumor primary, Sex, Sickness/comorbidity, and Site of radiotherapy model (METSSS), trained with registry-based data of patients treated with radiotherapy alone, are two of the most recently developed survival prediction models, but they have not been tested on patients whose local treatment strategy is not yet decided. (1) Which of these two survival prediction models performed better in a mixed cohort made up both of patients who received local treatment with surgery followed by radiotherapy and who had radiation alone for symptomatic bone metastases? (2) Which model performed better among patients whose local treatment consisted of only palliative radiotherapy? (3) Are laboratory values used by SORG-MLA, which are not included in METSSS, independently associated with survival after controlling for predictions made by METSSS? Between 2010 and 2018, we provided local treatment for 2113 adult patients with skeletal metastases in the extremities at an urban tertiary referral academic medical center using one of two strategies: (1) surgery followed by postoperative radiotherapy or (2) palliative radiotherapy alone. Every patient's survivorship status was ascertained either by their medical records or the national death registry from the Taiwanese National Health Insurance Administration. After applying a priori designated exclusion criteria, 91% (1920) were analyzed here. Among them, 48% (920) of the patients were female, and the median (IQR) age was 62 years (53 to 70 years). Lung was the most common primary tumor site (41% [782]), and 59% (1128) of patients had other skeletal metastases in addition to the treated lesion(s). In general, the indications for surgery were the presence of a complete pathologic fracture or an impending pathologic fracture, defined as having a Mirels score of ≥ 9, in patients with an American Society of Anesthesiologists (ASA) classification of less than or equal to IV and who were considered fit for surgery. The indications for radiotherapy were relief of pain, local tumor control, prevention of skeletal-related events, and any combination of the above. In all, 84% (1610) of the patients received palliative radiotherapy alone as local treatment for the target lesion(s), and 16% (310) underwent surgery followed by postoperative radiotherapy. Neither METSSS nor SORG-MLA was used at the point of care to aid clinical decision-making during the treatment period. Survival was retrospectively estimated by these two models to test their potential for providing survival probabilities. We first compared SORG to METSSS in the entire population. Then, we repeated the comparison in patients who received local treatment with palliative radiation alone. We assessed model performance by area under the receiver operating characteristic curve (AUROC), calibration analysis, Brier score, and decision curve analysis (DCA). The AUROC measures discrimination, which is the ability to distinguish patients with the event of interest (such as death at a particular time point) from those without. AUROC typically ranges from 0.5 to 1.0, with 0.5 indicating random guessing and 1.0 a perfect prediction, and in general, an AUROC of ≥ 0.7 indicates adequate discrimination for clinical use. Calibration refers to the agreement between the predicted outcomes (in this case, survival probabilities) and the actual outcomes, with a perfect calibration curve having an intercept of 0 and a slope of 1. A positive intercept indicates that the actual survival is generally underestimated by the prediction model, and a negative intercept suggests the opposite (overestimation). When comparing models, an intercept closer to 0 typically indicates better calibration. Calibration can also be summarized as log(O:E), the logarithm scale of the ratio of observed (O) to expected (E) survivors. A log(O:E) > 0 signals an underestimation (the observed survival is greater than the predicted survival); and a log(O:E) < 0 indicates the opposite (the observed survival is lower than the predicted survival). A model with a log(O:E) closer to 0 is generally considered better calibrated. The Brier score is the mean squared difference between the model predictions and the observed outcomes, and it ranges from 0 (best prediction) to 1 (worst prediction). The Brier score captures both discrimination and calibration, and it is considered a measure of overall model performance. In Brier score analysis, the "null model" assigns a predicted probability equal to the prevalence of the outcome and represents a model that adds no new information. A prediction model should achieve a Brier score at least lower than the null-model Brier score to be considered as useful. The DCA was developed as a method to determine whether using a model to inform treatment decisions would do more good than harm. It plots the net benefit of making decisions based on the model's predictions across all possible risk thresholds (or cost-to-benefit ratios) in relation to the two default strategies of treating all or no patients. The care provider can decide on an acceptable risk threshold for the proposed treatment in an individual and assess the corresponding net benefit to determine whether consulting with the model is superior to adopting the default strategies. Finally, we examined whether laboratory data, which were not included in the METSSS model, would have been independently associated with survival after controlling for the METSSS model's predictions by using the multivariable logistic and Cox proportional hazards regression analyses. Between the two models, only SORG-MLA achieved adequate discrimination (an AUROC of > 0.7) in the entire cohort (of patients treated operatively or with radiation alone) and in the subgroup of patients treated with palliative radiotherapy alone. SORG-MLA outperformed METSSS by a wide margin on discrimination, calibration, and Brier score analyses in not only the entire cohort but also the subgroup of patients whose local treatment consisted of radiotherapy alone. In both the entire cohort and the subgroup, DCA demonstrated that SORG-MLA provided more net benefit compared with the two default strategies (of treating all or no patients) and compared with METSSS when risk thresholds ranged from 0.2 to 0.9 at both 90 days and 1 year, indicating that using SORG-MLA as a decision-making aid was beneficial when a patient's individualized risk threshold for opting for treatment was 0.2 to 0.9. Higher albumin, lower alkaline phosphatase, lower calcium, higher hemoglobin, lower international normalized ratio, higher lymphocytes, lower neutrophils, lower neutrophil-to-lymphocyte ratio, lower platelet-to-lymphocyte ratio, higher sodium, and lower white blood cells were independently associated with better 1-year and overall survival after adjusting for the predictions made by METSSS. Based on these discoveries, clinicians might choose to consult SORG-MLA instead of METSSS for survival estimation in patients with long-bone metastases presenting for evaluation of local treatment. Basing a treatment decision on the predictions of SORG-MLA could be beneficial when a patient's individualized risk threshold for opting to undergo a particular treatment strategy ranged from 0.2 to 0.9. Future studies might investigate relevant laboratory items when constructing or refining a survival estimation model because these data demonstrated prognostic value independent of the predictions of the METSSS model, and future studies might also seek to keep these models up to date using data from diverse, contemporary patients undergoing both modern operative and nonoperative treatments. Level III, diagnostic study.

Lee CC ，Chen CW ，Yen HK ，Lin YP ，Lai CY ，Wang JL ，Groot OQ ，Janssen SJ ，Schwab JH ，Hsu FM ，Lin WH ... -  《-》

Vaccine preventable diseases and vaccination coverage in Aboriginal and Torres Strait Islander people, Australia 2006-2010.

This report outlines the major positive impacts of vaccines on the health of Aboriginal and Torres Strait Islander people from 2007 to 2010, as well as highlighting areas that require further attention. Hepatitis A disease is now less common in Aboriginal and Torres Strait Islander children than in their non-Indigenous counterparts. Hepatitis A vaccination for Aboriginal and Torres Strait Islander children was introduced in 2005 in the high incidence jurisdictions of the Northern Territory, Queensland, South Australia and Western Australia. In 2002–2005, there were 20 hospitalisations for hepatitis A in Aboriginal and Torres Strait Islander children aged<5 years--over 100 times more common than in other children--compared to none in 2006/07–2009/10. With respect to invasive pneumococcal disease (IPD), there has been a reduction of 87% in notifications of IPD caused by serotypes contained in 7-valent pneumococcal conjugate vaccine (7vPCV) since the introduction of the childhood 7vPCV program among Aboriginal and Torres Strait Islander children. However, due to a lower proportion of IPD caused by 7vPCV types prior to vaccine introduction, the decline in total IPD notifications has been less marked in Aboriginal and Torres Strait Islander children than in other children. Higher valency vaccines (10vPCV and 13vPCV) which replaced 7vPCV from 2011 are likely to result in a greater impact on IPD and potentially also non-invasive disease, although disease caused by non-vaccine serotypes appears likely to be an ongoing problem. Among Aboriginal and Torres Strait Islander people aged ≥50 years, there have been recent increases in IPD, which appear related to low vaccination coverage and highlight the need for improved coverage in this high-risk target group. Since routine meningococcal C vaccination for infants and the high-school catch-up program were implemented in 2003, there has been a significant decrease in cases caused by serogroup C. However, the predominant serogroup responsible for disease remains serogroup B, and Aboriginal and Torres Strait Islander children have significantly higher incidence of serogroup B disease than other children. A vaccine against meningococcus type B has now been licensed in Australia. The decline in severe rotavirus disease after vaccine introduction in 2007 was less marked in Aboriginal and Torres Strait Islander children than in other children. By far the highest hospitalisation rates continue to occur among Aboriginal and Torres Strait Islander children in the Northern Territory. Consideration of the role of age cut-offs and 2-dose versus 3-dose schedules may be necessary. Genotype surveillance is critically important to allow detection of any possible emergence of genotypes for which there is lower vaccine-derived immunity. Although Haemophilus influenzae type b disease rates have decreased significantly since the introduction of vaccines in 1993, the plateauing of rates in Aboriginal and Torres Strait Islander children, and increasing disparity with other children, are concerning. While it is possible that higher disease rates in young infants could be associated with the later age of protection from the newer 4-dose schedule, it is also possible that higher vaccine immunogenicity will result in reduced carriage. Close monitoring is important to detect any re-emergence of Hib disease as soon as possible. Pandemic and seasonal influenza and pneumonia are other diseases with comparatively higher rates in Aboriginal and Torres Strait Islander people. For Aboriginal and Torres Strait Islander people aged≥50 years, it is unclear whether or not there has been a decline in influenza hospitalisations since the start of the National Indigenous Pneumococcal and Influenza Immunisation Program in 1999, but hospitalisation rates are still higher in Aboriginal and Torres Strait Islander people. Achieving high coverage in those aged≥15 years should now be a priority. A prolonged mumps outbreak occurred in 2007/2008 predominantly affecting Aboriginal and Torres Strait Islander adolescents and young adults in north-western Australia. A potential contributor to this mumps outbreak was greater waning of immunity after receipt of the first dose of mumps-containing vaccine at 9, rather than 12, months of age in the Northern Territory in the 1980s and 1990s. However, outbreaks in Australia and overseas have subsided without additional boosters being routinely implemented. Pertussis epidemics continue to occur in Australia and affect both Aboriginal and Torres Strait Islander and other people. Parents are now encouraged to have their infant’s first vaccination given at 6 weeks of age, instead of the usual 2 months, and this is being successfully implemented for Aboriginal and Torres Strait Islander and other infants. Timely provision of the 4- and 6-month doses remains very important. High coverage for standard vaccines, poor timeliness of vaccination and lower coverage for ‘Indigenous only’ vaccines are continuing features of vaccination programs for Aboriginal and Torres Strait Islander people. There have been some improvements in vaccination timeliness in recent years for all children, but disparities remain between Aboriginal and Torres Strait Islander and other children. Poor timeliness reduces the potential benefits of vaccination, most importantly for pneumococcal, Hib and rotavirus vaccines in infants. The age cut-offs for rotavirus vaccines present a particular challenge for timely vaccination, limiting the capacity for catching up on late vaccination and resulting in lower overall coverage. This is more pronounced for the 3-dose than for the 2-dose rotavirus schedule. Coverage for vaccines recommended only for Aboriginal and Torres Strait Islander children continues to remain substantially lower than that for universal vaccines. This underlines the importance of immunisation providers establishing the Indigenous status of their clients, so that additional vaccines are offered as appropriate. The absence of any coverage data for Aboriginal and Torres Strait Islander adolescents, or for adults since 2004/2005, is a substantial obstacle to implementing and improving programs in these age groups.

Naidu L ，Chiu C ，Habig A ，Lowbridge C ，Jayasinghe S ，Wang H ，McIntyre P ，Menzies R ... -  《-》

Prevalences of overweight and obesity among children in remote Aboriginal communities in central Australia.

Schultz R 《Rural and Remote Health》