1,721,099 research outputs found
Calcium and Iron nutrition through the reproductive life course
No full textBackground: two essential micronutrients over the life course are calcium and iron, and both are especially important during the reproductive cycle. The role of calcium in maternal and offspring bone health and in the prevention of pre-eclampsia in pregnancy are well described, although results from randomised controlled trials for both outcomes vary. Iron is essential for synthesis of red blood cells, being a core component of haemoglobin, which carries oxygen around the body, and hence is key in the prevention of anaemia and sequelae.Summary: this article reviews the evidence across the reproductive life course for dietary calcium and iron intakes and health outcomes. For calcium, focusing on bone health and prevention of pre-eclampsia, for iron considering its crucial role in foetal and neonatal development and how requirements may be impacted through inflammation and infection, particularly in environments where iron availability may be low.</p
Cross-Calibration of iDXA and pQCT Scanners at Rural and Urban Research Sites in The Gambia, West Africa
Full text linkBetween-scanner differences in measures of bone and body composition can obscure or exaggerate physiological differences in multi-site studies or the magnitude of changes in longitudinal studies. We conducted a cross-calibration study at two bone imaging centres in The Gambia, West Africa where DXA (dual-energy X-ray absorptiometry) and pQCT (peripheral Quantitative-Computed Tomography) are routinely used. Repeat scans were obtained from 64 Gambian adults (58% Male) aged Mean(SD) 30.9 (13.5) years with Mean(SD) body mass index (BMI) 21.7 (4.0) kg/m2, using DXA (GE Lunar iDXA, whole body [WB], total hip [TH], lumbar spine [LS]) and pQCT (Stratec XCT2000L/XCT2000, tibia 4%, 50% sites). Between-scanner differences were tested using paired t tests (p
Multimorbidity and risk of falls, fractures, and joint replacements over two decades: Findings from the Hertfordshire Cohort Study
Full text linkAim: To examine the relationship between level of morbidity burden and long‐term risk of fractures, falls, and joint replacements in the community‐dwelling participants of the Hertfordshire Cohort Study. Methods: Data were analyzed from 2997 individuals (age 59–73 at baseline). Outcomes (fractures, falls, and lower limb joint replacements) were identified using ICD‐10 and OPCS‐4 codes from Hospital Episode Statistics data, available from baseline (1998–2004) until December 2018. Number of systems medicated (marker of morbidity level) in relation to risk of outcomes was examined using sex‐stratified Cox regression. Results: Among both men and women, a greater number of systems medicated was related to increased risk of falls (P < 0.001) and lower limb joint replacements (P < 0.003). More systems medicated was only related to increased risk of fracture among women (P‐values for trend of <0.001 among women and 0.186 among men). Conclusions: Higher morbidity was associated with increased risk of adverse health outcomes related to poor musculoskeletal health, but these relationships varied according to the musculoskeletal outcome studied. Intervention strategies to reduce multimorbidity among middle‐aged and older people may hence reduce the burden of musculoskeletal aging. Geriatr Gerontol Int 2024; ••: ••–••
Changes in bone mineral density, body composition, vitamin D status and mineral metabolism in urban HIV-positive South African women over 12 months
No full textHIV infection and antiretroviral therapy (ART) are associated with bone loss and poor vitamin D status in Caucasian populations, though their relative roles are not known. No previous studies have examined longitudinal changes in areal bone mineral density (aBMD), measured by DXA, or in vitamin D status in HIV-positive African women. Of 247 premenopausal, urban, black African women from Soweto, South Africa, initially recruited, 187 underwent anthropometry, DXA scanning and blood and urine collections at both baseline and 12 months. Of these, 67 were HIV-negative throughout (Nref), 60 were HIV-positive with preserved CD4 counts at baseline (Ppres) and 60 were HIV-positive with low CD4 counts at baseline, eligible for ART by South African standards of care at the time (Plow). No participant had been exposed to ART at baseline. By 12 months, 51 Plow women had initiated ART, >85% of whom took combined tenofovir disoproxil fumarate (TDF), lamivudine and efavirenz. By 12 months, Plow and Nref, but not Ppres, increased in body weight and fat mass (group-by-timepoint p ≤0.001, p = 0.002 respectively). Plow had significant decreases in aBMD of 2-3%, before and after size adjustment, at the femoral neck (p ≤0.002) and lumbar spine (p ≤0.001), despite significant weight gain. These decreases were associated with increased bone turnover but there were no significant differences or changes over time in vitamin D status, serum phosphate concentrations or renal phosphate handling. Excluding data from 9 Plow women unexposed to ART and 11 Ppres women who had initiated ART accentuated these findings, suggesting the bone loss in Plow was related to ART exposure. This is the first study describing DXA-defined bone loss in HIV-positive Sub-Saharan African women in association with ART. Further work is required to establish if bone loss continues with on-going ART and, if so, whether this results in increased fracture rates
Cluster analysis of finite element analysis and bone microarchitectural parameters identifies phenotypes with high fracture risk
No full textHigh-resolution peripheral quantitative computed tomography (HRpQCT) is increasingly used for exploring associations between bone microarchitectural and finite element analysis (FEA) parameters and fracture. We hypothesised that combining bone microarchitectural parameters, geometry, BMD and FEA estimates of bone strength from HRpQCT may improve discrimination of fragility fractures. The analysis sample comprised of 359 participants (aged 72–81 years) from the Hertfordshire Cohort Study. Fracture history was determined by self-report and vertebral fracture assessment. Participants underwent HRpQCT scans of the distal radius and DXA scans of the proximal femur and lateral spine. Poisson regression with robust variance estimation was used to derive relative risks for the relationship between individual bone microarchitectural and FEA parameters and previous fracture. Cluster analysis of these parameters was then performed to identify phenotypes associated with fracture prevalence. Receiver operating characteristic analysis suggested that bone microarchitectural parameters improved fracture discrimination compared to aBMD alone, whereas further inclusion of FEA parameters resulted in minimal improvements. Cluster analysis (k-means) identified four clusters. The first had lower Young modulus, cortical thickness, cortical volumetric density and Von Mises stresses compared to the wider sample; fracture rates were only significantly greater among women (relative risk [95%CI] compared to lowest risk cluster: 2.55 [1.28, 5.07], p = 0.008). The second cluster in women had greater trabecular separation, lower trabecular volumetric density and lower trabecular load with an increase in fracture rate compared to lowest risk cluster (1.93 [0.98, 3.78], p = 0.057). These findings may help inform intervention strategies for the prevention and management of osteoporosis
Hospital admissions and mortality over 20 years in community-dwelling older people: findings from the Hertfordshire Cohort Study
No full textBackground: demographic changes worldwide are leading to pressures on health services, with hospital admissions representing an important contributor. Here, we report admission types experienced by older people and examine baseline risk factors for subsequent admission/death, from the community-based Hertfordshire Cohort Study. Methods: 2997 participants (1418 women) completed a baseline questionnaire and clinic visit to characterize their health. Participants were followed up from baseline (1998–2004, aged 59–73 years) until December 2018 using UK Hospital Episode Statistics and mortality data, which report clinical outcomes using ICD-10 coding. Baseline characteristics in relation to the risk of admission/death during follow-up were examined using sex-stratified univariate logistic regression. Results: during follow-up, 36% of men and 26% of women died and 93% of men and 92% of women had at least one hospital admission; 6% of men and 7% of women had no admissions and were alive at end of follow-up. The most common types of admission during follow-up were cardiovascular (ever experienced: men 71%, women 68%) and respiratory (men 40%, women 34%). In both sexes, baseline risk factors that were associated (p < 0.05) with admission/death during follow-up were older age, poorer SF-36 physical function, and poorer self-rated health. In men, manual social class and a history of smoking, and in women, higher BMI, not owning one’s home, and a minor trauma fracture since age 45, were also risk factors for admission/death. Conclusions: sociodemographic factors were related to increased risk of admission/death but a small proportion experienced no admissions during this period, suggesting that healthy ageing is achievable.</p
Life course dietary patterns and bone health in later life in a British birth cohort study
No full textEvidence for the contribution of individual foods and nutrients to bone health is weak. Few studies have considered hypothesis-based dietary patterns and bone health. We investigated whether a protein, calcium and potassium-rich (PrCaK-rich) dietary pattern over the adult life course, was positively associated with bone outcomes at 60-64 years of age. Diet diaries were collected at ages 36, 46, 53 and 60-64 years in 1263 participants (661 women) from the MRC National Survey of Health and Development. DXA and pQCT measurements were obtained at 60-64y, including size-adjusted bone mineral content (SA-BMC) and volumetric bone mineral density (vBMD). A food-based dietary pattern best explaining dietary calcium, potassium and protein intakes (g/1000?kcal) was identified using reduced rank regression. Dietary pattern z-scores were calculated for each individual, at each time point. Individual trajectories in dietary pattern z-scores were modelled to summarise changes in z-scores over the study period. Regression models examined associations between these trajectories and bone outcomes at 60-64y, adjusting for baseline dietary pattern z-score and other confounders. A consistent PrCaK-rich dietary pattern was identified within the population, over time. Mean [SD] dietary pattern z-scores at age 36 and 60-64 years were -0.32[0.97], 2.2[1.5] (women) and -0.35[0.98], 1.7[1.6] (men). Mean trajectory in dietary pattern z-scores [SD] was 0.07[0.02]SD units/year. Among women, a 0.02 SD unit/year higher trajectory in dietary pattern z-score over time was associated with higher SA-BMC (spine 1.40% [95% CI: 0.30,2.51]; hip 1.35% [95% CI: 0.48,2.23]) and vBMD (radius 1.81% [95% CI: 0.13,3.50]) at 60-64 y. No statistically significant associations were found in men. During adulthood, an increasing score for a dietary pattern rich in protein, calcium and potassium was associated with greater SA-BMC at fracture-prone sites in women. This study emphasises the importance of these nutrients, within the context of the whole diet, to bone healt
Associations of markers of inflammatory dtatus and adiposity with bone phenotype at age 60-64 years: findings from the MRC National Survey of Health and Development
Full text linkThis study investigated associations between markers of inflammatory status and adiposity (interleukin-6 [IL-6], adiponectin and leptin) and measures of bone phenotype and fractures. The Medical Research Council (MRC) National Survey of Health and Development (NSHD) is a British birth cohort study. Participants (born during the same week in 1946) with complete data on DXA and pQCT parameters, markers of inflammatory status and adiposity, and potential confounders (498 men and 474 women) were included in cross-sectional analyses. At age 60–64 years, bone phenotype was assessed by DXA and pQCT. Fractures were self-reported at ages 60–64 and 68–70 years. Multiple linear regression was used to determine associations of IL-6, adiponectin and leptin with bone phenotype (adjusted for fat and lean mass and lifestyle confounders). Standard deviation (SD) differences in outcomes per SD increases in exposures were estimated. Higher IL-6 levels were associated with lower total volumetric bone mineral density (vBMD) (− 0.10[− 0.19, 0.00]) in men, and higher areal BMD (aBMD) at the spine (0.12[0.03, 0.22]) and whole body (0.11[0.01, 0.20]) in women. Higher levels of adiponectin were associated with lower aBMD and trabecular vBMD. In women, higher leptin levels were associated with higher cortical vBMD (0.11[0.02, 0.20]). Higher adiponectin was associated with moderately increased odds of having a fragility fracture during adulthood in women (OR 1.16 [95% CI 0.94, 1.43, p = 0.18]). Our results highlight non-mechanical associations between markers of inflammatory status and adiposity with BMD and, in women, fractures. Ensuring inflammaging is minimised may be important in healthy bone ageing
Are jumping mechanography assessed muscle force and power, and traditional physical capability measures associated with falls in older adults? Results from the Hertfordshire Cohort Study
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