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Vegetable nitrate intake, blood pressure and incident cardiovascular disease: Danish Diet, Cancer, and Health Study
Abstract
Whether the vascular effects of inorganic nitrate, observed in clinical trials, translate to a reduction in cardiovascular disease (CVD) with habitual dietary nitrate intake in prospective studies warrants investigation. We aimed to determine if vegetable nitrate, the major dietary nitrate source, is associated with lower blood pressure (BP) and lower risk of incident CVD. Among 53,150 participants of the Danish Diet, Cancer, and Health Study, without CVD at baseline, vegetable nitrate intake was assessed using a comprehensive vegetable nitrate database. Hazard ratios (HRs) were calculated using restricted cubic splines based on multivariable-adjusted Cox proportional hazards models. During 23 years of follow-up, 14,088 cases of incident CVD were recorded. Participants in the highest vegetable nitrate intake quintile (median, 141 mg/day) had 2.58 mmHg lower baseline systolic BP (95%CI − 3.12, − 2.05) and 1.38 mmHg lower diastolic BP (95%CI − 1.66, − 1.10), compared with participants in the lowest quintile. Vegetable nitrate intake was inversely associated with CVD plateauing at moderate intakes (~ 60 mg/day); this appeared to be mediated by systolic BP (21.9%). Compared to participants in the lowest intake quintile (median, 23 mg/day), a moderate vegetable nitrate intake (median, 59 mg/day) was associated with 15% lower risk of CVD [HR (95% CI) 0.85 (0.82, 0.89)]. Moderate vegetable nitrate intake was associated with 12%, 15%, 17% and 26% lower risk of ischemic heart disease, heart failure, ischemic stroke and peripheral artery disease hospitalizations respectively. Consumption of at least ~ 60 mg/day of vegetable nitrate (~ 1 cup of green leafy vegetables) may mitigate risk of CVD.
Abdominal Aortic Calcification, Bone Mineral Density, and Fractures: A Systematic Review and Meta-analysis of Observational Studies
Abstract
Background: Abdominal aortic calcification (AAC) has been inconsistently associated with skeletal health. We aimed to investigate the association of AAC with bone mineral density (BMD) and fracture risk by pooling the findings of observational studies.
Methods: MEDLINE, EMBASE, Web of Science, and Google Scholar were searched (August 2021). All clinical studies that assessed the association between AAC and BMD or fracture were included. AAC was categorized into any/advanced (all higher reported groups) versus no/ less advanced (lowest reported group). Pooled standardized mean differences (SMDs) and risk ratios (RRs) with 95% confidence intervals (CI) were determined for BMD and fracture, respectively, using random-effects models.
Results: Of 2 192 articles screened, 86 (61 553 participants) were included in the review, while 42 provided data for meta-analysis. AAC was associated with lower BMD at the total hip (SMD = −1.05 [95%CI: −1.47 to −0.63]; 16 studies), femoral neck (−0.25 [−0.46 to−0.04]; 10), and lumbar spine (−0.67 [−1.21 to −0.12]; 20). AAC was associated with a greater risk of any fracture (RR = 1.73 [95%CI: 1.48–2.02]; 27). AAC was also associated with vertebral, non-vertebral, and hip fractures. In dose–response analysis, the highest AAC group had greater risks of any, vertebral and non-vertebral fractures.
Conclusions: AAC is associated with lower BMD and increased fracture risk at multiple sites, underscoring the potential importance of vascular disease on skeletal health. Detection of AAC at the time of BMD testing may provide clinicians with prognostic information about bone health to enhance osteoporosis screening programs and fracture risk prediction.
Calcaneal quantitative ultrasound is associated with all‑cause and cardiovascular disease mortality independent of hip bone mineral density
Abstract
Summary: Osteoporosis has been linked with increased risk of cardiovascular disease previously. However, few studies have detailed bone and vascular information. In a prospective study of older women, we demonstrated heel quantitative ultrasound measures were associated with increased cardiovascular and all-cause mortality, independent of established cardiovascular risk factors.
Introduction: Osteoporosis and low bone mineral density (BMD) have been previously linked to cardiovascular disease (CVD) and mortality. Calcaneal quantitative ultrasound (QUS) is used to evaluate bone material properties, especially in older women. However, it is uncertain whether it is related to risk of mortality. This study was aimed to investigate the association between calcaneal QUS measurements and 15-year all-cause and CVD mortality in 1404 older women (mean age 75.2 ± 2.7 years).
Methods: One thousand four hundred four older women, participants of Calcium Intake Fracture Outcome study (CAIFOS), had calcaneal bone measured at baseline (1998) and followed for 15 years. The primary outcomes, any deaths, and deaths attributable to cardiovascular causes ascertained by using linked data were obtained from Western Australia data linkage system.
Results: Over the 15 years of follow-up (17,955 person years), 584 of the women died, and 223 from CVD. For every standard deviation (SD), reduction in broadband ultrasound attenuation (BUA) in minimally and multivariable-adjusted model including cardiovascular risk factors increased relative hazards for all-cause (multivariable-adjusted HR 1.15; 95%CI: 1.06–1.26, p = 0.001) and CVD mortality (multivariable-adjusted HR 1.20; 95%CI: 1.04–1.38, p = 0.010). Such relationships also persisted when hip BMD was included in the model (all-cause mortality HR 1.19; 95%CI: 1.07–1.33, p = 0.002; CVD mortality HR 1.28; 95%CI: 1.07–1.53, p = 0.008).
Conclusion: BUA is associated with all-cause and CVD mortality in older women independent of BMD and established CVD risk factors. Understanding why and how these are related may provide further insights about the bone-vascular nexus as well as therapeutic targets benefiting both systems.
Prognostic Value of Abdominal Aortic Calcification: A Systematic Review and Meta-Analysis of Observational Studies
Abstract
Background: The prognostic importance of abdominal aortic calcification (AAC) viewed on noninvasive imaging modalities remains uncertain.
Methods and Results: We searched electronic databases (MEDLINE and Embase) until March 2018. Multiple reviewers identified prospective studies reporting AAC and incident cardiovascular events or all‐cause mortality. Two independent reviewers assessed eligibility and risk of bias and extracted data. Summary risk ratios (RRs) were estimated using random‐effects models comparing the higher AAC groups combined (any or more advanced AAC) to the lowest reported AAC group. We identified 52 studies (46 cohorts, 36 092 participants); only studies of patients with chronic kidney disease (57%) and the general older‐elderly (median, 68 years; range, 60–80 years) populations (26%) had sufficient data to meta‐analyze. People with any or more advanced AAC had higher risk of cardiovascular events (RR, 1.83; 95% CI, 1.40–2.39), fatal cardiovascular events (RR, 1.85; 95% CI, 1.44–2.39), and all‐cause mortality (RR, 1.98; 95% CI, 1.55–2.53). Patients with chronic kidney disease with any or more advanced AAC had a higher risk of cardiovascular events (RR, 3.47; 95% CI, 2.21–5.45), fatal cardiovascular events (RR, 3.68; 95% CI, 2.32–5.84), and all‐cause mortality (RR, 2.40; 95% CI, 1.95–2.97).
Conclusions: Higher‐risk populations, such as the elderly and those with chronic kidney disease with AAC have substantially greater risk of future cardiovascular events and poorer prognosis. Providing information on AAC may help clinicians understand and manage patients’ cardiovascular risk better.
Calcium Supplementation and the Risks of Atherosclerotic Vascular Disease in Older Women: Results of a 5-Year RCT and a 4.5-Year Follow-up
Abstract
Concern has been expressed that calcium supplementation, a key intervention for preventing osteoporotic fracture in older women, may increase the risk of atherosclerotic vascular disease. To evaluate the risk further, an examination of complete verified atherosclerotic vascular hospitalization and mortality data from a 5-year randomized, controlled trial (RCT) of calcium carbonate and 4.5 years of posttrial follow-up was undertaken. This study used data from a published 5-year randomized, double-blinded, placebo-controlled trial [Calcium Intake Fracture Outcome Study (CAIFOS)]. The participants were 1460 women aged 75.1 ± 2.7 years at baseline (1998) recruited from the general population and randomized to receive 1200 mg of calcium carbonate daily or an identical placebo. All hospital admission and deaths during the 5-year study and the 4.5-year follow-up were derived from the Western Australian Data Linkage Service (WADLS). Hazard ratios (HRs) for the combined endpoint of atherosclerotic vascular mortality or first hospitalization were calculated using prespecified intention-to-treat and per-protocol models. The intervention group that received calcium supplementation did not have a higher risk of death or first-time hospitalization from atherosclerotic vascular disease in either the 5-year RCT [multivariate-adjusted HR = 0.938, 95% confidence interval (CI) 0.690–1.275] or during the 9.5 years of observational study (multivariate-adjusted HR = 0.919, 95% CI 0.737–1.146). Further analysis suggested that calcium supplementation may reduce the risk of hospitalization and mortality in patients with preexisting atherosclerotic cardiovascular disease. This trial provides compelling evidence that calcium supplementation of 1200 mg daily does not significantly increase the risk of atherosclerotic vascular disease in elderly women. © 2011 American Society for Bone and Mineral Research.
The Effects of 3 Years of Calcium Supplementation on Common Carotid Artery Intimal Medial Thickness and Carotid Atherosclerosis in Older Women: An Ancillary Study of the CAIFOS Randomized Controlled Trial
Abstract
Calcium is an essential nutrient for skeletal health; however, it has been suggested that supplemental calcium may be associated with adverse cardiovascular effects, raising widespread concern about their use. One suggested mechanism is via increasing carotid atherosclerosis, however few randomized controlled trials (RCT) of calcium supplements have assessed these mechanisms. The calcium intake fracture outcome study (CAIFOS) was a 5-year RCT (1998 to 2003) of 1.2 g of elemental calcium in the form of calcium carbonate in 1460 elderly women. An ancillary study of 1103 women assessed common carotid artery intimal medial thickness (CCA-IMT) and carotid atherosclerosis at year 3 (2001). The effects of supplementation were studied in intention-to-treat (ITT) and per-protocol (PP) analyses before and after adjustment for baseline cardiovascular risk factors. The mean age of participants at baseline was 75.2 ± 2.7 years. In ITT analyses, women randomized to calcium supplementation had no difference in multivariable-adjusted mean CCA-IMT (calcium 0.778 ± 0.006 mm, placebo 0.783 ± 0.006 mm, p = 0.491) and maximum CCA-IMT (calcium 0.921 ± 0.007 mm, placebo 0.929 ± 0.006 mm, p = 0.404). Women randomized to calcium did not have increased carotid atherosclerosis (calcium 47.2%, placebo 52.7%, p = 0.066). However, in women taking at least 80% of the supplements, a significant reduction in carotid atherosclerosis was observed in unadjusted but not in multivariate-adjusted models (p = 0.033 and p = 0.064, respectively). Participants in the highest tertile of total calcium (diet and supplements) had reduced carotid atherosclerosis in unadjusted and multivariable-adjusted analyses compared with participants in the lowest tertile (odds ratio [OR] = 0.67 [95% confidence interval (CI) 0.50–0.90], p = 0.008, and OR = 0.70 [95% CI 0.51–0.96], p = 0.028, respectively). In conclusion, these findings do not support the hypothesis that calcium supplementation increases carotid artery intimal medial thickness or carotid atherosclerosis, and high calcium intake may reduce this surrogate cardiovascular risk factor. © 2014 American Society for Bone and Mineral Research.
Association Between Abdominal Aortic Calcification, Bone Mineral Density, and Fracture in Older Women
Abstract
Although a relationship between vascular disease and osteoporosis has been recognized, its clinical importance for fracture risk evaluation remains uncertain. Abdominal aortic calcification (AAC), a recognized measure of vascular disease detected on single-energy images performed for vertebral fracture assessment, may also identify increased osteoporosis risk. In a prospective 10-year study of 1024 older predominantly white women (mean age 75.0 ± 2.6 years) from the Perth Longitudinal Study of Aging cohort, we evaluated the association between AAC, skeletal structure, and fractures. AAC and spine fracture were assessed at the time of hip densitometry and heel quantitative ultrasound. AAC was scored 0 to 24 (AAC24) and categorized into low AAC (score 0 and 1, n = 459), moderate AAC (score 2 to 5, n = 373), and severe AAC (score >6, n = 192). Prevalent vertebral fractures were calculated using the Genant semiquantitative method. AAC24 scores were inversely related to hip BMD ( r s = –0.077, p = 0.013), heel broadband ultrasound attenuation ( r s = –0.074, p = 0.020), and the Stiffness Index ( r s = –0.073, p = 0.022). In cross-sectional analyses, women with moderate to severe AAC were more likely to have prevalent fracture and lumbar spine imaging-detected lumbar spine fractures, but not thoracic spine fractures (Mantel-Haenszel test of trend p < 0.05). For 10-year incident clinical fractures and fracture-related hospitalizations, women with moderate to severe AAC (AAC24 score >1) had increased fracture risk (HR 1.48; 95% CI, 1.15 to 1.91; p = 0.002; HR 1.46; 95% CI, 1.07 to 1.99; p = 0.019, respectively) compared with women with low AAC. This relationship remained significant after adjusting for age and hip BMD for clinical fractures (HR 1.40; 95% CI, 1.08 to 1.81; p = 0.010), but was attenuated for fracture-related hospitalizations (HR 1.33; 95% CI, 0.98 to 1.83; p = 0.073). In conclusion, older women with more marked AAC are at higher risk of fracture, not completely captured by bone structural predictors. These findings further support the concept that vascular calcification and bone pathology may share similar mechanisms of causation that remain to be fully elucidated © 2019 American Society for Bone and Mineral Research
Development of a Vitamin K Database for Commercially Available Food in Australia
Abstract
Vitamin K content of foods is known to vary substantially by geographical location. In Australia, no Vitamin K database of food exists, thereby creating ambiguity when trying to develop national dietary intake guidelines. This investigation aimed to develop a Vitamin K database for commonly consumed foods that are commercially available in Australian supermarkets. The Vitamin K1 (phylloquinone; PK) and K2 (menaquinone; MK4, MK7) content of 60 foods known to contain Vitamin K were assessed (e.g., vegetables fruits, oils, animal products, dairy and fermented foods). A liquid chromatography with tandem mass spectrometry (LCMS/MS) method was developed and used to measure PK and MKs in different foods with an improved chromatographic separation and detection of Vitamin K’s and their analogs. The LOD and LOQ for PK and MK4 was 0.1, 0.5 ng/ml and 0.5, 1.0 ng/ml, respectively. The majority foods contained detectable PK (53/60), about half contained MK4 (31/60), and few contained MK7 (3/60). PK was highest in green leafy vegetables, with moderate amounts in oils. Highest MK4 content was in chicken eggs and meat products such as ham and chicken. This database enables nutritional epidemiologist to estimate dietary Vitamin K intake, especially in Australian cohorts, for a range of health outcomes.
Abdominal aortic calcification on lateral spine images captured during bone density testing and late-life dementia risk in older women: A prospective cohort study
Abstract
Background: Dementia after the age of 80 years (late-life) is increasingly common due to vascular and non-vascular risk factors. Identifying individuals at higher risk of late-life dementia remains a global priority.
Methods: In prospective study of 958 ambulant community-dwelling older women (≥70 years), lateral spine images (LSI) captured in 1998 (baseline) from a bone density machine were used to assess abdominal aortic calcification (AAC). AAC was classified into established categories (low, moderate and extensive). Cardiovascular risk factors and apolipoprotein E (APOE) genotyping were evaluated. Incident 14.5-year late-life dementia was identified from linked hospital and mortality records.
Findings: At baseline women were 75.0 ± 2.6 years, 44.7% had low AAC, 36.4% had moderate AAC and 18.9% had extensive AAC. Over 14.5- years, 150 (15.7%) women had a late-life dementia hospitalisation (n = 132) and/or death (n = 58). Compared to those with low AAC, women with moderate and extensive AAC were more likely to suffer late-life dementia hospitalisations (9.3%, 15.5%, 18.3%, respectively) and deaths (2.8%, 8.3%, 9.4%, respectively). After adjustment for cardiovascular risk factors and APOE, women with moderate and extensive AAC had twice the relative hazards of late-life dementia (moderate, aHR 2.03 95%CI 1.38–2.97; extensive, aHR 2.10 95%CI 1.33–3.32), compared to women with low AAC.
Interpretation: In community-dwelling older women, those with more advanced AAC had higher risk of late-life dementia, independent of cardiovascular risk factors and APOE genotype. Given the widespread use of bone density testing, simultaneously capturing AAC information may be a novel, non-invasive, scalable approach to identify older women at risk of late-life dementia.
Funding: Kidney Health Australia, Healthway Health Promotion Foundation of Western Australia, Sir Charles Gairdner Hospital Research Advisory Committee Grant, National Health and Medical Research Council of Australia.
Impaired muscle function, including its decline, is related to greater long-term late-life dementia risk in older women
Abstract
Background: Impaired muscle function has been identified as a risk factor for declining cognitive function and cardiovascular health, both of which are risk factors for late-life dementia (after 80 years of age). We examined whether hand grip strength and timed-up-and-go (TUG) performance, including their change over 5 years, were associated with late-life dementia events in older women and whether any associations provided independent information to Apolipoprotein E ℇ4 (APOE ℇ4) genotype.
Methods: Grip strength and TUG were assessed in community-dwelling older women (mean ± SD; age 75.0 ± 2.6 years) at baseline (n = 1225) and 5 years (n = 1052). Incident 14.5-year late-life dementia events (dementia-related hospitalization/death) were obtained from linked health records. Cardiovascular risk factors (Framingham Risk Score), APOE genotyping, prevalent atherosclerotic vascular disease and cardiovascular-related medications were evaluated at baseline. These were included in multivariable-adjusted Cox-proportional hazards models assessing the relationship between muscle function measures and late-life-dementia events.
Results: Over follow-up, 207 (16.9%) women had a late-life dementia event. Compared with women with the highest grip strength (Quartile [Q] 4, 25.8 kg), those with the lowest grip strength (Q1, 16.0 kg) had greater hazard for a late-life dementia event (HR 2.27 95% CI 1.54–3.35, P < 0.001). For TUG, the slowest women (Q4, 12.4 vs. Q1, 7.4 s) also recorded a greater hazard for a late-life dementia event (HR 2.10 95% CI 1.42–3.10, P = 002). Weak hand grip (<22 kg) or slow TUG (>10.2 s) provided independent information to the presence of an APOE ℇ4 allele (n = 280, 22.9%). Compared with women with no weakness and no APOE ℇ4 allele, those with weakness and APOE ℇ4 allele had a greater hazard (HR 3.19 95% CI 2.09–4.88, P < 0.001) for a late-life dementia event. Women presenting with slowness and the APOE ℇ4 allele also recorded a greater hazard for a late-life dementia event (HR 2.59 95% CI 1.64–4.09, P < 0.001). For 5-year muscle function changes, compared with women with the lowest performance decrement (Q1), those with the largest decrement (Q4) had higher hazards for a late-life dementia event (grip strength HR 1.94 95% CI 1.22–3.08, P = 0.006; TUG HR 2.52 95% CI 1.59–3.98, P < 0.001) over the next 9.5 years.
Conclusions: Weaker grip strength and slower TUG, and a greater decline over 5 years, were significant risk factors for a late-life-dementia event in community-dwelling older women, independent of lifestyle and genetic risk factors. Incorporating muscle function measures as part of dementia screening appears useful to identify high-risk individuals who might benefit from primary prevention programmes.
Dietary Vitamin K1 intake is associated with lower long-term fracture-related hospitalization risk: the Perth longitudinal study of ageing women
Abstract
This study examined the association between dietary Vitamin K1 intake with fracture-related hospitalizations over 14.5 years in community-dwelling older Australian women (n = 1373, ≥70 years). Dietary Vitamin K1 intake at baseline (1998) was estimated using a validated food frequency questionnaire and a new Australian Vitamin K nutrient database, which was supplemented with published data. Over 14.5 years, any fracture (n = 404, 28.3%) and hip fracture (n = 153, 10.7%) related hospitalizations were captured using linked health data. Plasma Vitamin D status (25OHD) and the ratio of undercarboxylated osteocalcin (ucOC) to total osteocalcin (tOC) from serum was assessed at baseline. Estimates of dietary Vitamin K1 intake were supported by a significant inverse association with ucOC : tOC; a marker of Vitamin K status (r = −0.12, p < 0.001). Compared to women with the lowest Vitamin K1 intake (Quartile 1, <61 μg d−1), women with the highest Vitamin K1 intake (Quartile 4, ≥99 μg d−1) had lower hazards for any fracture- (HR 0.69 95%CI 0.52–0.91, p < 0.001) and hip fracture-related hospitalization (HR 0.51 95%CI 0.32–0.79, p < 0.001), independent of 25OHD levels, as part of multivariable-adjusted analysis. Spline analysis suggested a nadir in the relative hazard for any fracture-related hospitalizations at a Vitamin K1 intake of approximately 100 μg day−1. For hip fractures, a similar relationship was apparent. Higher dietary Vitamin K1 is associated with lower long-term risk for any fracture- and hip fracture-related hospitalizations in community-dwelling older women.
Higher Dietary Vitamin K Intake is Associated with Better Physical Function and Lower Long-Term Injurious Falls Risk in Community-Dwelling Older Women
Abstract
Background: In recent years, a potential beneficial role of Vitamin K in neuromuscular function has been recognised. However, the optimal dietary intake of Vitamin K to support muscle function in the context of falls prevention remains unknown.
Objective: To examine the relationship of dietary Vitamin K1 and K2 with muscle function and long-term injurious fall-related hospitalisations in older women.
Design: Cohort study.
Participants: 1347 community-dwelling older Australian women≥70 years.
Measurements: A new Australian Vitamin K nutrient database, supplemented with published data, was used to calculate Vitamin K1 and K2 intake from a validated food frequency questionnaire at baseline (1998). Muscle function (grip strength and timed-up-and-go; TUG) as well plasma Vitamin D status (25OHD) were also assessed at baseline. Fall-related hospitalisations over 14.5 years were obtained from linked health records. Multivariable-adjusted logistic regression and Cox-proportional hazard models were used to analyse the data.
Results: Over 14.5 years of follow-up (14,774 person-years), 535 (39.7%) women experienced a fall-related hospitalisation. Compared to women with the lowest Vitamin K1 intake (Quartile 1, median 49 μg/d), those with the highest intake (Quartile 4, median 120 μg/d) had 29% lower odds (OR 0.71 95%CI 0.52-0.97) for slow TUG performance (>10.2 s), and 26% lower relative hazards of a fallrelated hospitalisation (HR 0.74 95%CI 0.59-0.93) after multivariable adjustment. These associations were non-linear and plateaued at moderate intakes of ~70-100 μg/d. There was no relation to grip strength. Vitamin K2 intakes were not associated with muscle function or falls.
Conclusion: A higher habitual Vitamin K1 intake was associated with better physical function and lower long-term injurious falls risk in community-dwelling older women. In the context of musculoskeletal health, Vitamin K1 found abundantly in green leafy vegetables should be promoted.
The effects of vitamin K-rich green leafy vegetables on bone metabolism: A 4-week randomised controlled trial in middle-aged and older individuals
Abstract
Background: High vegetable intake is associated with beneficial effects on bone. However, the mechanisms remain uncertain. Green leafy vegetables are a rich source of vitamin K1, which is known to have large effects on osteoblasts and osteocalcin (OC) metabolism.
Objective: To examine the effects of consumption of two to three extra serves of green leafy vegetables daily on bone metabolism.
Methods: Thirty individuals (mean age 61.8 ± 9.9 years, 67% male) completed three experimental phases in a randomised controlled crossover design, each lasting four weeks, with a washout period of four weeks between phases (clinical trial registration: ACTRN12615000194561). The three experimental phases were: (i) increased dietary vitamin K1 by consuming green leafy vegetables (H-K; ~200 g/d containing 164.3 [99.5–384.7] μg/d of vitamin K1); (ii) low vitamin K1 by consuming vitamin K1-poor vegetables (L-K; ~200 g/d containing 9.4 [7.7–11.6] μg/d of vitamin K1); and (iii) control (CON) where participants consumed an energy-matched nonvegetable control. OC forms, total OC (tOC), carboxylated OC (cOC) and undercarboxylated OC (ucOC), were measured in serum pre- and post-intervention for each experimental phase using a sandwich- electrochemiluminescence immunoassay.
Results: Pre-intervention tOC, ucOC and ucOC:tOC levels were similar between phases (P > .05). Following HK, but not L-K, tOC, ucOC and ucOC:tOC levels were significantly lower compared to pre- intervention levels (P ≤ .001) and compared to CON (~14%, 31% and 19%, respectively, all P < .05), while cOC remained unchanged.
Conclusions: In middle-aged healthy men and women, an easily achieved increase in dietary intake of vitamin.
Creatinine to Cystatin C Ratio, a Biomarker of Sarcopenia Measures and Falls Risk in Community-Dwelling Older Women
Abstract
Background: The ratio of creatinine to cystatin C (Cr:Cyc) has been proposed as a biomarker of sarcopenia, as greater Cr:Cyc is typically associated with greater muscle mass. We examined the relationship between Cr:Cyc with individual sarcopenia measures, 5-year self-reported falls, and 12-year fall-related hospitalizations in a prospective cohort study of 1 118 community-dwelling older women (mean age 75.2 ± 2.7 years).
Methods: Serum Cr:Cyc, hand grip strength, and timed-up-and-go performance were assessed at baseline (1998), while dual-energy x-ray absorptiometry-derived appendicular lean mass (ALM)/height2 (m) was obtained in a subset of women at baseline and 1 year (n = 334). Incident 5-year self-reported falls and 12-year falls-related hospitalizations were considered.
Results: In a multivariable-adjusted model, women with the lowest Cr:Cyc (Quartile [Q] 1) had 5% (1.0 kg) weaker grip strength, as well as 3.7% (0.22 kg/m2) and 5.5% (0.031) lower ALM adjusted for height2 or body mass index, respectively, compared to women in Q4 (all p < .05). 329 women reported an incident fall over 5 years, and 326 fall-related hospitalizations were recorded over 12 years. Women in Q1 of Cr:Cyc had a greater relative hazard for a fall over 5 years (hazard ratio [HR] 1.50; 95% confidence interval [CI] 1.11–2.01) and fall-related hospitalization over 12 years (HR 1.53; 95% CI 1.13–2.07) compared to Q4 in the multivariable-adjusted model.
Conclusion: These findings support further investigation into the use of Cr:Cyc as a muscle biomarker to help clinicians identify individuals at risk of falls for early inclusion into evidence-based primary prevention programs targeting improvements to diet and exercise.
Utility of four sarcopenia criteria for the prediction of falls-related hospitalization in older Australian women
Abstract
Summary: Numerous sarcopenia definitions are not associated with increased falls-related hospitalization risk over 5 years to 9.5 years in older community-dwelling Australian women. Measures of muscle strength and physical function, but not appendicular lean mass (measured by dual-energy X-ray absorptiometry) may help discriminate the risk of falls-related hospitalization.
Introduction: The aim of this prospective, population-based cohort study of 903 Caucasian-Australian women (mean age 79.9 ± 2.6 years) was to compare the clinical utility of four sarcopenia definitions for the prediction of falls-related hospitalization over 9.5 years.
Methods: The four definitions were the United States Foundation for the National Institutes of Health (FNIH), the European Working Group on Sarcopenia in Older People (EWGSOP), and modified FNIH (AUS-POPF) and EWGSOP (AUS-POPE) definitions using Australian population-specific cut points (< 2 SD below the mean of young healthy Australian women). Components of sarcopenia including muscle strength, physical function, and appendicular lean mass (ALM) were quantified using hand grip strength, timed-up-and-go (TUG), and dual-energy X-ray absorptiometry (DXA), respectively. Incident 9.5-year falls-related hospitalization were captured by linked data.
Results: Baseline prevalence of sarcopenia according to FNIH (9.4%), EWGSOP (24.1%), AUS-POPF (12.0%), and AUS-POPE (10.7%) differed substantially. Sarcopenia did not increase the relative hazard ratio (HR) for falls-related hospitalization before or after adjustment for age (aHR): FNIH aHR 1.00 95%CI (0.69–1.47), EWGSOP aHR 1.20 95%CI (0.93–1.54), AUS-POPF aHR 0.96 95%CI (0.68–1.35), and AUS-POPE aHR 1.33 95%CI (0.94–1.88). When examining individual components of sarcopenia, only muscle strength and physical function but not ALM (adjusted for height2 or BMI) were associated with falls-related hospitalization.
Conclusion: Current definitions of sarcopenia were not associated with falls-related hospitalization risk in this cohort of community-dwelling older Australian women. Finally, measures of muscle strength and physical function, but not ALM (measured by DXA) may help discriminate the risk of falls-related hospitalization.
Machine learning for abdominal aortic calcification assessment from bone density machine-derived lateral spine images
Abstract
Background: Lateral spine images for vertebral fracture assessment can be easily obtained on modern bone density machines. Abdominal aortic calcification (AAC) can be scored on these images by trained imaging specialists to assess cardiovascular disease risk. However, this process is laborious and requires careful training.
Methods: Training and testing of model performance of the convolutional neural network (CNN) algorithm for automated AAC-24 scoring utilised 5012 lateral spine images (2 manufacturers, 4 models of bone density machines), with trained imaging specialist AAC scores. Validation occurred in a registry-based cohort study of 8565 older men and women with images captured as part of routine clinical practice for fracture risk assessment. Cox proportional hazards models were used to estimate the association between machine-learning AAC (ML-AAC-24) scores with future incident Major Adverse Cardiovascular Events (MACE) that including death, hospitalised acute myocardial infarction or ischemic cerebrovascular disease ascertained from linked healthcare data.
Findings: The average intraclass correlation coefficient between imaging specialist and ML-AAC-24 scores for 5012 images was 0.84 (95% CI 0.83, 0.84) with classification accuracy of 80% for established AAC groups. During a mean follow-up 4 years in the registry-based cohort, MACE outcomes were reported in 1177 people (13.7%). With increasing ML-AAC-24 scores there was an increasing proportion of people with MACE (low 7.9%, moderate 14.5%, high 21.2%), as well as individual MACE components (all p-trend <0.001). After multivariable adjustment, moderate and high ML-AAC-24 groups remained significantly associated with MACE (HR 1.54, 95% CI 1.31–1.80 & HR 2.06, 95% CI 1.75–2.42, respectively), compared to those with low ML-AAC-24.
Interpretation: The ML-AAC-24 scores had substantial levels of agreement with trained imaging specialists, and was associated with a substantial gradient of risk for cardiovascular events in a real-world setting. This approach could be readily implemented into these clinical settings to improve identification of people at high CVD risk.
Funding: The study was supported by a National Health and Medical Research Council of Australia Ideas grant and the Rady Innovation Fund, Rady Faculty of Health Sciences, University of Manitoba.