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"Armstrong, Bruce K."
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Vitamin D supplementation and risk of falling: outcomes from the randomized, placebo‐controlled D‐Health Trial
by
Webb, Penelope M.
,
Venn, Alison J.
,
Duarte Romero, Briony
in
Accidental Falls - prevention & control
,
Aged
,
Australia - epidemiology
2021
Background Falls cause considerable morbidity and mortality in older people. It is unclear how vitamin D supplementation affects falls risk, particularly when taken at high doses. We sought to determine whether monthly high‐dose vitamin D supplementation reduces risk and incidence of falls. Methods We used data from the randomized, double‐blind, placebo‐controlled D‐Health Trial conducted in Australia. Between February 2014 and May 2015, 21 315 participants aged 60–84 years were randomized (1:1) to monthly doses of either 60 000 IU of colecalciferol or placebo for a maximum of 5 years. People who reported a history of osteomalacia, sarcoidosis, hyperparathyroidism, hypercalcaemia or kidney stones or who were taking >500 IU/day supplementary vitamin D were ineligible. Each year, we collected blood samples from ~450 randomly sampled participants from each trial arm and measured 25‐hydroxyvitamin D [25(OH)D]. Falls, a prespecified tertiary outcome, were ascertained using annual surveys and, for a subset of participants, 3‐month falls diaries. The primary outcome for this analysis was any fall in the month before completing an annual survey. As part of our process to maintain blinding, we used random samples of participants (surveys, n = 16 000; diaries, n = 2400), with equal numbers per group. Participants with no outcome data were excluded. Following an intention‐to‐treat approach, we analysed outcomes using logistic, ordinal and negative binomial regression. Registration: Australian New Zealand Clinical Trials Registry (ACTRN12613000743763); registered 4 July 2013. Results Mean treatment duration was 4.3 years (standard deviation [SD] = 1.4 years). Mean serum 25(OH)D concentrations during the trial were 114.8 (SD 30.3) nmol/L and 77.5 (SD 25.2) nmol/L in the vitamin D and placebo groups, respectively. Survey and diary analytic sets included 15 416 and 2200 participants, respectively; approximately half were randomized to vitamin D (surveys: 50.1%; diaries: 50.4%). Vitamin D had no effect on falling in the past month (odds ratio [OR] 1.02, 95% confidence interval [CI] 0.95–1.10). There was an interaction with body mass index (BMI) (P‐interaction = 0.001); vitamin D increased risk in participants with BMI < 25 kg/m2 (OR 1.25, 95% CI 1.09–1.43), but there was no effect in those with BMI ≥ 25 kg/m2 (OR 0.95, 95% CI 0.87–1.04). Analyses of diary data were consistent with these findings. The incidence of hypercalcaemia and kidney stones did not differ between groups. Conclusions Monthly high‐dose vitamin D supplementation did not reduce risk of falling. A possible increased risk of falling with vitamin D supplementation in people with normal BMI warrants further investigation.
Journal Article
Poor Adherence to National Clinical Management Guidelines: A Population-Based, Cross-Sectional Study of the Surgical Management of Melanoma in New South Wales, Australia
by
Cust, Anne E.
,
Thompson, John F.
,
Madronio, Christine M.
in
Aged
,
Australia - epidemiology
,
Biopsy
2017
Background
Standardization of the clinical management of melanoma through the formulation of national guidelines, based on interpretation of the existing evidence and consensus expert opinion, seeks to improve quality of care; however, adherence to national guidelines has not been well studied.
Methods
A population-based, cross-sectional study of the clinical management of all patients with newly notified primary melanomas in the state of New South Wales, Australia, during 2006/2007 was conducted using cancer registry identification and questionnaires completed by treating physicians.
Results
Surgical margin guidelines were adhered to in 35% of cases; 45% were over treated and 21% were undertreated. Factors independently associated with non-concordance on multivariate analysis were lower Breslow thickness, lower socio-economic status of the physician’s practice location, older physician age, lower physician caseload, and physicians who biopsied the lesion and then referred for definitive management. Complications were not related to over- or under-treatment on multivariate analysis (
p
= 0.72). Sentinel lymph node biopsy was performed in 17% of patients with invasive melanoma, with the main determinant for selection being a Breslow thickness >0.75 mm.
Conclusions
The low level of concordance with national guidelines for surgical management of melanoma resulted in overtreatment of many patients. However, a fifth of patients were undertreated, which is likely to have resulted in increased locoregional recurrence rates. The better concordance achieved by physicians treating >30 melanomas per year suggests that a minimum caseload threshold for physicians treating melanoma patients would be desirable. High guideline concordance will ensure patients receive optimal care and minimize morbidity and health service costs.
Journal Article
Plasma micronutrient levels and telomere length in children
by
de Klerk, Nicholas H.
,
Greenop, Kathryn R.
,
Armstrong, Bruce K.
in
adults
,
Blood
,
blood sampling
2015
Telomeres are long hexamer (TTAGGG) repeats at the ends of chromosomes, and contribute to maintenance of chromosomal stability. Telomere shortening has been linked to cancers and other chronic diseases in adults, although evidence for causal associations is limited. The aim of this study was to determine whether nutritional factors are associated with telomere length (TL) in children.
We conducted a cross-sectional study of nutritional factors and TL in 437 children between 2009 and 2011. Healthy children ages 3, 6, and 9 y provided blood samples, and their parents completed a food frequency questionnaire and a telephone interview about relevant environmental exposures. TL and blood micronutrient levels were measured, and genotyping at 10 loci was undertaken. Associations between the micronutrients and other variables were assessed using linear regression.
No significant main or interactive effects of age or sex were seen. After adjustment for age, sex, parental education, and month of blood collection, TL was inversely associated with plasma zinc, and shorter in children with the homozygous mutant genotype of the RFC G80A (rs1051266) polymorphism.
To the best of our knowledge, this is the first investigation of the association between telomere length and micronutrients in healthy children. The reason for the inverse relationship of TL with zinc is unknown but could be the result of an increase in telomere sequence deletions caused by labile zinc induction of oxidative stress. These findings should be corroborated in other studies before nutritional recommendations might be considered.
•Association between telomere length and blood micronutrients were investigated.•Nine polymorphisms of genes related to folate metabolism/DNA damage also were assessed.•Participants were healthy children ages 3, 6, or 9 y.•Telomere length was inversely associated with plasma zinc levels in the child.•Telomere length was associated with the reduced folate-carrier polymorphism.
Journal Article
Using administrative health data to describe colorectal and lung cancer care in New South Wales, Australia: a validation study
by
O’Connell, Dianne L
,
Simonella, Leonardo
,
Goldsbury, David E
in
Adult
,
Aged
,
Aged, 80 and over
2012
Background
Monitoring treatment patterns is crucial to improving cancer patient care. Our aim was to determine the accuracy of linked routinely collected administrative health data for monitoring colorectal and lung cancer care in New South Wales (NSW), Australia.
Methods
Colorectal and lung cancer cases diagnosed in NSW between 2000 and 2002 were identified from the NSW Central Cancer Registry (CCR) and linked to their hospital discharge records in the NSW Admitted Patient Data Collection (APDC). These records were then linked to data from two relevant population-based patterns of care surveys. The main outcome measures were the sensitivity and specificity of data from the CCR and APDC for disease staging, investigative procedures, curative surgery, chemotherapy, radiotherapy, and selected comorbidities.
Results
Data for 2917 colorectal and 1580 lung cancer cases were analysed. Unknown disease stage was more common for lung cancer in the administrative data (18%) than in the survey (2%). Colonoscopies were captured reasonably accurately in the administrative data compared with the surveys (82% and 79% respectively; 91% sensitivity, 53% specificity) but all other colorectal or lung cancer diagnostic procedures were under-enumerated. Ninety-one percent of colorectal cancer cases had potentially curative surgery recorded in the administrative data compared to 95% in the survey (96% sensitivity, 92% specificity), with similar accuracy for lung cancer (16% and 17%; 92% sensitivity, 99% specificity). Chemotherapy (~40% sensitivity) and radiotherapy (sensitivity≤30%) were vastly under-enumerated in the administrative data. The only comorbidity that was recorded reasonably accurately in the administrative data was diabetes.
Conclusions
Linked routinely collected administrative health data provided reasonably accurate information on potentially curative surgical treatment, colonoscopies and comorbidities such as diabetes. Other diagnostic procedures, comorbidities, chemotherapy and radiotherapy were not well enumerated in the administrative data. Other sources of data will be required to comprehensively monitor the primary management of cancer patients.
Journal Article
Associations between sun sensitive pigmentary genes and serum prostate specific antigen levels
2018
Melanoma and prostate cancer may share risk factors. This study examined the association between serum PSA levels, which is a risk factor for prostate cancer, and variants in some melanoma-associated pigmentary genes.
We studied participants, all aged 70+ years, in the Concord Health and Ageing in Men Project who had no history of prostatitis or received treatment for prostate disease (n = 1033). We genotyped variants in MC1R (rs1805007, rs1805008), ASIP (rs4911414, rs1015362), SLC45A2 (rs28777, rs16891982), IRF4 (rs12203592), TYRP1 (rs1408799), TYR (rs1126809, rs1042602), SLC24A2 (rs12896399), and OCA2 (rs7495174). Generalised linear dominant models with Poisson distribution, log link functions and robust variance estimators estimated adjusted percentage differences (%PSA) in mean serum PSA levels (ng/mL) between variant and wildtype (0%PSA = reference) genotypes, adjusting for age, body mass index, serum 25OHD levels and birth regions (Australia or New Zealand (ANZ), Europe or elsewhere).
Serum PSA levels were strongly associated with advancing age and birth regions: mean PSA levels were lower in Europe-born (-29.7%) and elsewhere-born (-11.7%) men than ANZ-born men (reference). Lower %PSA was observed in men with variants in SLC45A2: rs28777 (-19.6;95%CI: -33.5, -2.7), rs16891982 (-17.3;95%CI:-30.4,-1.7) than in wildtype men (reference). There were significant interactions between birth regions and PSA levels in men with variants in MC1R (rs1805007; p-interaction = 0.0001) and ASIP (rs4911414; p-interaction = 0.007). For these genes %PSA was greater in ANZ-born men and lower in Europe- and elsewhere-born men with the variant than it was in wildtype men. In a post hoc analysis, serum testosterone levels were increased in men with MC1R rs1805007 and serum dihydrotestosterone in men with ASIP rs1015362.
Men with SNPs in SLC45A2, who have less sun sensitive skin, have lower PSA levels. Men with SNPs in MC1R and ASIP, who have more sun sensitive skin, and were born in ANZ, have higher PSA levels. Androgens may modify these apparent associations of pigmentary genes and sun exposure with PSA levels.
PSA levels and possibly prostate cancer risk may vary with sun sensitivity and sun exposure, the effects of which might be modified by androgen levels.
Journal Article
Sun exposure and skin cancer, and the puzzle of cutaneous melanoma: A perspective on Fears et al. Mathematical models of age and ultraviolet effects on the incidence of skin cancer among whites in the United States. American Journal of Epidemiology 1977; 105: 420-427
by
Armstrong, Bruce K
,
Cust, Anne E
in
Age Factors
,
Carcinoma, Basal Cell - epidemiology
,
Carcinoma, Squamous Cell - epidemiology
2017
Sunlight has been known as an important cause of skin cancer since around the turn of the 20th Century. A 1977 landmark paper of US scientists Fears, Scotto, and Schneiderman advanced a novel hypothesis whereby cutaneous melanoma was primarily caused by intermittent sun exposure (i.e. periodic, brief episodes of exposure to high-intensity ultraviolet radiation) while the keratinocyte cancers, squamous cell carcinoma and basal cell carcinoma, were primarily caused by progressive accumulation of sun exposure. With respect to cutaneous melanoma, this became known as the intermittent exposure hypothesis. The hypothesis stemmed from analysis of measured ambient ultraviolet radiation and age-specific incidence rates of melanoma and keratinocyte cancers collected as an extension to the US Third National Cancer Survey in several US States. In this perspective paper, we put this novel hypothesis into the context of knowledge at the time, and describe subsequent epidemiological and molecular research into melanoma that elaborated the intermittent exposure hypothesis and ultimately replaced it with a dual pathway hypothesis. Our present understanding is of two distinct biological pathways by which cutaneous melanoma might develop; a nevus prone pathway initiated by early sun exposure and promoted by intermittent sun exposure or possibly host factors; and a chronic sun exposure pathway in sun sensitive people who progressively accumulate sun exposure to the sites of future melanomas.
Journal Article
Confirmation of Childhood Acute Lymphoblastic Leukemia Variants, ARID5B and IKZF1, and Interaction with Parental Environmental Exposures
by
de Klerk, Nicholas H.
,
Catchpoole, Daniel
,
Bowden, Nikola A.
in
Acids
,
Acute lymphatic leukemia
,
Acute lymphoblastic leukemia
2014
Genome wide association studies (GWAS) have established association of ARID5B and IKZF1 variants with childhood acute lymphoblastic leukemia (ALL). Epidemiological studies suggest that environmental factors alone appear to make a relatively minor contribution to disease risk. The polygenic nature of childhood ALL predisposition together with the timing of environmental triggers may hold vital clues for disease etiology. This study presents results from an Australian GWAS of childhood ALL cases (n = 358) and population controls (n = 1192). Furthermore, we utilised family trio (n = 204) genotypes to extend our investigation to gene-environment interaction of significant loci with parental exposures before conception, and child's sex and age. Thirteen SNPs achieved genome wide significance in the population based case/control analysis; ten annotated to ARID5B and three to IKZF1. The most significant SNPs in these regions were ARID5B rs4245595 (OR 1.63, CI 1.38-1.93, P = 2.13×10(-9)), and IKZF1 rs1110701 (OR 1.69, CI 1.42-2.02, p = 7.26×10(-9)). There was evidence of gene-environment interaction for risk genotype at IKZF1, whereby an apparently stronger genetic effect was observed if the mother took folic acid or if the father did not smoke prior to pregnancy (respective interaction P-values: 0.04, 0.05). There were no interactions of risk genotypes with age or sex (P-values >0.2). Our results evidence that interaction of genetic variants and environmental exposures may further alter risk of childhood ALL however, investigation in a larger population is required. If interaction of folic acid supplementation and IKZF1 variants holds, it may be useful to quantify folate levels prior to initiating use of folic acid supplements.
Journal Article
Common Gene Variants in the Tumor Necrosis Factor (TNF) and TNF Receptor Superfamilies and NF-kB Transcription Factors and Non-Hodgkin Lymphoma Risk
2009
A promoter polymorphism in the pro-inflammatory cytokine tumor necrosis factor (TNF) (TNF G-308A) is associated with increased non-Hodgkin lymphoma (NHL) risk. The protein product, TNF-alpha, activates the nuclear factor kappa beta (NF-kappaB) transcription factor, and is critical for inflammatory and apoptotic responses in cancer progression. We hypothesized that the TNF and NF-kappaB pathways are important for NHL and that gene variations across the pathways may alter NHL risk.
We genotyped 500 tag single nucleotide polymorphisms (SNPs) from 48 candidate gene regions (defined as 20 kb 5', 10 kb 3') in the TNF and TNF receptor superfamilies and the NF-kappaB and related transcription factors, in 1946 NHL cases and 1808 controls pooled from three independent population-based case-control studies. We obtained a gene region-level summary of association by computing the minimum p-value (\"minP test\"). We used logistic regression to compute odds ratios and 95% confidence intervals for NHL and four major NHL subtypes in relation to SNP genotypes and haplotypes. For NHL, the tail strength statistic supported an overall relationship between the TNF/NF-kappaB pathway and NHL (p = 0.02). We confirmed the association between TNF/LTA on chromosome 6p21.3 with NHL and found the LTA rs2844484 SNP most significantly and specifically associated with the major subtype, diffuse large B-cell lymphoma (DLBCL) (p-trend = 0.001). We also implicated for the first time, variants in NFKBIL1 on chromosome 6p21.3, associated with NHL. Other gene regions identified as statistically significantly associated with NHL included FAS, IRF4, TNFSF13B, TANK, TNFSF7 and TNFRSF13C. Accordingly, the single most significant SNPs associated with NHL were FAS rs4934436 (p-trend = 0.0024), IRF4 rs12211228 (p-trend = 0.0026), TNFSF13B rs2582869 (p-trend = 0.0055), TANK rs1921310 (p-trend = 0.0025), TNFSF7 rs16994592 (p-trend = 0.0024), and TNFRSF13C rs6002551 (p-trend = 0.0074). All associations were consistent in each study with no apparent specificity for NHL subtype.
Our results provide consistent evidence that variation in the TNF superfamily of genes and specifically within chromosome 6p21.3 impacts lymphomagenesis. Further characterization of these susceptibility loci and identification of functional variants are warranted.
Journal Article
Fifteen year quality of life outcomes in men with localised prostate cancer: population based Australian prospective study
by
King, Madeleine T
,
Smith, David P
,
Mazariego, Carolyn G
in
Androgens
,
Brachytherapy
,
Cancer surgery
2020
AbstractObjectiveTo assess treatment related changes in quality of life up to 15 years after diagnosis of localised prostate cancer.DesignPopulation based, prospective cohort study with follow-up over 15 years.SettingNew South Wales, Australia.Participants1642 men with localised prostate cancer, aged less than 70, and 786 controls randomly recruited from the New South Wales electoral roll into the New South Wales Prostate Cancer Care and Outcomes Study (PCOS).Main outcome measuresGeneral health and disease specific quality of life were self-reported at seven time points over a 15 year period, using the 12-item Short Form Health Survey scale, University of California, Los Angeles prostate cancer index, and expanded prostate cancer index composite short form (EPIC-26). Adjusted mean differences were calculated with controls as the comparison group. Clinical significance of adjusted mean differences was assessed by the minimally important difference, defined as one third of the standard deviation (SD) from the baseline score.ResultsAt 15 years, all treatment groups reported high levels of erectile dysfunction, depending on treatment (62.3% (active surveillance/watchful waiting, n=33/53) to 83.0% (non-nerve sparing radical prostatectomy, n=117/141)) compared with controls (42.7% (n=44/103)). Men who had external beam radiation therapy or high dose rate brachytherapy or androgen deprivation therapy as primary treatment reported more bowel problems. Self-reported urinary incontinence was particularly prevalent and persistent for men who underwent surgery, and an increase in urinary bother was reported in the group receiving androgen deprivation therapy from 10 to 15 years (year 10: adjusted mean difference −5.3, 95% confidence interval −10.8 to 0.2; year 15: −15.9; −25.1 to −6.7).ConclusionsPatients receiving initial active treatment for localised prostate cancer had generally worse long term self-reported quality of life than men without a diagnosis of prostate cancer. Men treated with radical prostatectomy faired especially badly, particularly in relation to long term sexual outcomes. Clinicians and patients should consider these long term quality of life outcomes when making treatment decisions.
Journal Article
High-dose vitamin D supplementation to prevent prostate cancer progression in localised cases with low-to-intermediate risk of progression on active surveillance (ProsD): protocol of a phase II randomised controlled trial
2021
IntroductionActive surveillance (AS) for patients with prostate cancer (PC) with low risk of PC death is an alternative to radical treatment. A major drawback of AS is the uncertainty whether a patient truly has low risk PC based on biopsy alone. Multiparametric MRI scan together with biopsy, appears useful in separating patients who need curative therapy from those for whom AS may be safe. Two small clinical trials have shown short-term high-dose vitamin D supplementation may prevent PC progression. There is no substantial evidence for its long-term safety and efficacy, hence its use in the care of men with PC on AS needs assessment. This protocol describes the ProsD clinical trial which aims to determine if oral high-dose vitamin D supplementation taken monthly for 2 years can prevent PC progression in cases with low-to-intermediate risk of progression.Method and analysisThis is an Australian national multicentre, 2:1 double-blinded placebo-controlled phase II randomised controlled trial of monthly oral high-dose vitamin D supplementation (50 000 IU cholecalciferol), in men diagnosed with localised PC who have low-to-intermediate risk of disease progression and are being managed by AS. This trial will assess the feasibility, efficacy and safety of supplementing men with an initial oral loading dose of 500 000 IU cholecalciferol, followed by a monthly oral dose of 50 000 IU during the 24 months of AS. The primary trial outcome is the commencement of active therapy for clinical or non-clinical reason, within 2 years of AS.Ethics and disseminationThis trial is approved by Bellberry Ethics Committee (2016-06-459). All results will be reported in peer-reviewed journals.Trial registration numberACTRN12616001707459.
Journal Article