High-flow nasal cannula therapy for infants with bronchiolitis

BACKGROUND

Bronchiolitis is a common lower respiratory tract illness, usually of viral aetiology, affecting infants younger than 24 months of age and is the most common cause of hospitalisation of infants. It causes airway inflammation, mucus production and mucous plugging, resulting in airway obstruction. Effective pharmacotherapy is lacking and bronchiolitis is a major cause of morbidity and mortality. Conventional treatment consists of supportive therapy in the form of fluids, supplemental oxygen, and respiratory support. Traditionally, oxygen delivery is as a dry gas at 100% concentration via low-flow nasal prongs. However, the use of heated, humidified, high-flow nasal cannula (HFNC) therapy enables delivery of higher inspired gas flows of an air/oxygen blend, at 2 to 3 L/kg per minute up to 60 L/min in children. It can provide some level of continuous positive airway pressure (CPAP) to improve ventilation in a minimally invasive manner. This may reduce the need for invasive respiratory support, thus potentially lowering costs, with clinical advantages and fewer adverse effects.

OBJECTIVES

To assess the effects of HFNC therapy compared with conventional respiratory support in the treatment of infants with bronchiolitis.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, LILACS, and Web of Science (from June 2013 to December 2022). In addition, we consulted ongoing trial registers and experts in the field to identify ongoing studies, checked reference lists of relevant articles, and searched for conference abstracts. Date restrictions were imposed such that we only searched for studies published after the original version of this review.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) or quasi-RCTs that assessed the effects of HFNC (delivering oxygen or oxygen/room air blend at flow rates greater than 4 L/minute) compared to conventional treatment in infants (< 24 months) with a clinical diagnosis of bronchiolitis.

DATA COLLECTION AND ANALYSIS

Two review authors independently used a standard template to assess trials for inclusion and extract data on study characteristics, risk of bias elements, and outcomes. We contacted trial authors to request missing data. Outcome measures included the need for invasive respiratory support and time until discharge, clinical severity measures, oxygen saturation, duration of oxygen therapy, and adverse events.

MAIN RESULTS

In this update we included 15 new RCTs (2794 participants), bringing the total number of RCTs to 16 (2813 participants). Of the 16 studies, 11 compared high-flow to low-flow, and five compared high-flow to CPAP. These studies included infants less than 24 months of age as stated in our selection criteria. There were no significant differences in sex. We found that when comparing high-flow to low-flow oxygen therapy for infants with bronchiolitis there may be a reduction in the total length of hospital stay (mean difference (MD) -0.65 days, 95% confidence interval (CI) -1.23 to -0.06; P < 0.00001, I2 = 89%; 7 studies, 1951 participants; low-certainty evidence). There may also be a reduction in the duration of oxygen therapy (MD -0.59 days, 95% CI -1 to -0.18; P < 0.00001, I2 = 86%; 7 studies, 2132 participants; low-certainty evidence). We also found that there was probably an improvement in respiratory rate at one and 24 hours, and heart rate at one, four to six, and 24 hours in those receiving high-flow oxygen therapy when compared to pre-intervention baselines. There was also probably a reduced risk of treatment escalation in those receiving high-flow when compared to low-flow oxygen therapy (risk ratio (RR) 0.55, 95% CI 0.39 to 0.79; P = 0.001, I2 = 43%; 8 studies, 2215 participants; moderate-certainty evidence). We found no difference in the incidence of adverse events (RR 1.2, 95% CI 0.38 to 3.74; P = 0.76, I2 = 26%; 4 studies, 1789 participants; low-certainty evidence) between the two groups. The lack of comparable outcomes in studies comparing high-flow and CPAP, as well as the small numbers of participants, limited our ability to perform meta-analysis on this group.

AUTHORS' CONCLUSIONS

High-flow nasal cannula therapy may have some benefits over low-flow oxygen for infants with bronchiolitis in terms of a greater improvement in respiratory and heart rates, as well as a modest reduction in the length of hospital stay and duration of oxygen therapy, with a reduced incidence of treatment escalation. There does not appear to be a difference in the number of adverse events. Further studies comparing high-flow nasal cannula therapy and CPAP are required to demonstrate the efficacy of one modality over the other. A standardised clinical definition of bronchiolitis, as well as the use of a validated clinical severity score, would allow for greater and more accurate comparison between studies.

Assessing health state utilities for people with myalgic encephalomyelitis/chronic fatigue syndrome in Australia using the EQ-5D-5L, AQoL-8D and EQ-5D-5L-psychosocial instruments

PURPOSE

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic condition with a constellation of symptoms presenting as severe and profound fatigue of ≥ 6 months not relieved by rest. ME/CFS affects health-related quality of life (HRQoL), which can be measured using multi-attribute health state utility (HSU) instruments. The aims of this study were to quantify HSUs for people living with ME/CFS, and to identify an instrument that is preferentially sensitive for ME/CFS.

METHODS

Cross-sectional national survey of people with ME/CFS using the AQoL-8D and EQ-5D-5L. Additional questions from the AQoL-8D were used as 'bolt-ons' to the EQ-5D-5L (i.e., EQ-5D-5L-Psychosocial). Disability and fatigue severity were assessed using the De Paul Symptom Questionnaire-Short Form (DSQ-SF). HSUs were generated using Australian tariffs. Mean HSUs were stratified for sociodemographic and clinical factors. Bland-Altman plots were used to compare the three HSU instruments.

RESULTS

For the 198 participants, mean HSUs (95% confidence intervals) were EQ-5D-5L: 0.46 (0.42-0.50); AQoL-8D: 0.43 (0.41-0.45); EQ-5D-5L-Psychosocial: 0.44 (0.42-0.46). HSUs were substantially lower than population norms: EQ-5D-5L: 0.89; AQoL-8D: 0.77. As disability and fatigue severity increased, HSUs decreased in all three instruments. Bland-Altman plots revealed interchangeability between the AQoL-8D and EQ-5D-5LPsychosocial. Floor and ceiling effects of 13.5% and 2.5% respectively were observed for the EQ-5D-5L instrument only.

CONCLUSIONS

ME/CFS has a profound impact on HRQoL. The AQoL-8D and EQ-5D-5L-Psychosocial can be used interchangeably: the latter represents a reduced participant burden.

The economic burden of myalgic encephalomyelitis/chronic fatigue syndrome in Australia

Objective This study aimed to estimate costs of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) to patients, government and Australian society. Methods Australian ME/CFS patients and their carers were recruited using convenience sampling. Patients completed an online retrospective cost diary, providing ME/CFS-related direct medical, non-medical and indirect costs. Informal care costs were collected directly from carers. Data from the Pharmaceutical Benefits Scheme and Medicare Benefits Schedule were linked to participant survey data. Annual per patient and total societal costs were estimated, broken down by category and presented in 2021 AUD. Factors associated with higher costs were investigated using generalised linear models. Results One hundred and seventy five patients (mean age 49 years s.d. 14, 79.4% female) completed the cost diary. Estimated total annual societal costs of ME/CFS in Australia ranged between $1.38 and $10.09 billion, with average annual total costs of $63 400/patient. Three-quarters of these costs were due to indirect costs ($46 731). Disability severity was the key factor associated with higher costs, particularly for indirect costs (being 2.27-fold higher for severe disability than no/mild disability). Conclusions ME/CFS poses a significant economic burden in Australia, owing mainly to high indirect and informal care costs.

Health Literacy predicts incident foot ulcers after 4 years - the SHELLED cohort study

AIMS/HYPOTHESIS

To determine whether health literacy is associated with an index diabetes-related foot ulcer (DFU).

METHODS

The SHELLED Study is a 4-year prospective study of people with diabetes aged over 40 with no history of DFU. The primary outcome was development of a first foot ulcer. Health Literacy was measured using the short form Test of Functional Health Literacy in Adults (s-TOFHLA) and nine domains of the Health Literacy Questionnaire (HLQ).

RESULTS

Of 222 participants, 191 (86.0%) completed the study, of whom 13 (5.9%) developed an incident ulcer. In multivariable models, every unit increase in S-TOFHLA was associated with a reduced odds of foot ulcer development by 6% (OR 0.94, 95% CI 0.88 to 0.99). Better scores on two HLQ domains reduced the odds of foot ulcer (actively managing my health (OR 0.23, 95% CI 0.08 to 0.65) and understanding health information well enough to know what to do (OR 0.39, 95% CI 0.19 to 0.78). This was independent of baseline risk for foot disease.

CONCLUSIONS/INTERPRETATION

These data provide novel evidence that health literacy is an important clinical risk factor for index foot ulceration. This is an area of potential focus for research and development of educational programs or policy aimed at reducing development of incident foot ulceration.

Impacts of life-events on sitting, TV viewing and computer use among women from disadvantaged neighbourhoods

Background

Little is known about how life events such as changes in parental or employment status influence sedentary behaviour (SB). Women from disadvantaged neighbourhoods are at particular risk of poor health, therefore, in this population group this study aimed to determine between changes in parental and employment status with sitting, television viewing (TV), and computer time.

Methods

Women (18–45 years) from socioeconomically disadvantaged neighbourhoods self-reported their employment status, number of children, sitting, TV, and computer time [(baseline (n = 4349), three (n = 1912) and 5 years (n = 1560)]. Linear (sitting) and negative binomial (TV and computer time) multilevel models adjusted for confounders were used to estimate the SB association with changes in life events.

Results

Compared to women who never had children during the study period, less sitting and computer time was observed for women when number of children remained unchanged, had their first child or additional child, and fewer children (< 18 years). Less TV was observed for women when number of children remained unchanged.

Compared to women who remained employed full-time during the study period, sitting and computer time decreased among women when they decreased or increased their working hours or when remained employed part-time/not working. TV time increased among women when they decreased their working hours.

Conclusion

Among women, declines in SB were observed amongst those experiencing life events. Interventions to decrease SB may consider targeting women with no children, and future research should further explore how changes in employment type (e.g., non-manual to manual jobs) impact SB.

MYC sensitises cells to apoptosis by driving energetic demand

The MYC oncogene is a potent driver of growth and proliferation but also sensitises cells to apoptosis, which limits its oncogenic potential. MYC induces several biosynthetic programmes and primary cells overexpressing MYC are highly sensitive to glutamine withdrawal suggesting that MYC-induced sensitisation to apoptosis may be due to imbalance of metabolic/energetic supply and demand. Here we show that MYC elevates global transcription and translation, even in the absence of glutamine, revealing metabolic demand without corresponding supply. Glutamine withdrawal from MRC-5 fibroblasts depletes key tricarboxylic acid (TCA) cycle metabolites and, in combination with MYC activation, leads to AMP accumulation and nucleotide catabolism indicative of energetic stress. Further analyses reveal that glutamine supports viability through TCA cycle energetics rather than asparagine biosynthesis and that TCA cycle inhibition confers tumour suppression on MYC-driven lymphoma in vivo. In summary, glutamine supports the viability of MYC-overexpressing cells through an energetic rather than a biosynthetic mechanism.

Cognition, educational attainment and diabetes distress predict poor health literacy in diabetes: A cross-sectional analysis of the SHELLED study

Objectives

To identify factors that predict poor health literacy amongst people with diabetes.

Design

Cross-sectional analysis of baseline data from a prospective study of diabetic foot disease.

Setting

Patients attending a tertiary hospital diabetes outpatient clinic in Tasmania, Australia.

Participants

222 people with diabetes mellitus, aged >40 years, with no history of foot ulceration, psychotic disorders or dementia.

Outcome measures

Health literacy was measured using the short form Test of Functional Health Literacy in Adults (functional health literacy), and the Health Literacy Questionnaire (HLQ), which measures nine domains of health literacy. Predictors included demographic characteristics, cognition, diabetes distress, depression, and educational attainment.

Results

In multivariable analysis, greater educational attainment (OR 0.88, 95% CI 0.76, 0.99) and poorer cognition (OR 0.71, 95% CI 0.63, 0.79) were associated with poorer functional health literacy. Age was negatively associated with domains of appraisal of health information and ability to find good health information (both beta = -0.01). Educational attainment was positively associated with four domains, namely having sufficient information to manage my health, actively managing my health, appraisal of and ability to find good health information (beta ranging from +0.03 to 0.04). Diabetes distress was negatively associated with five domains: having sufficient information to manage my health, social support for health, ability to actively engage with healthcare providers, navigating the healthcare system and ability to find good health information (beta ranging from -0.14 to -0.18).

Conclusion

Poorer cognition and poorer educational attainment may be detrimental for an individual’s functional health literacy, and education, diabetes distress and older age detrimental across multiple health literacy domains. Clinicians and policy makers should be attuned to these factors when communicating with people with diabetes and in designing healthcare systems to be more health-literacy friendly in order to improve diabetes outcomes.

Calcaneal bone marrow lesions and plantar fascia imaging biomarkers are associated with chronic plantar heel pain: a case-control study

OBJECTIVE

To determine associations between chronic plantar heel pain (CPHP) and MRI- and US-derived imaging biomarkers.

METHODS

We compared 218 participants with CPHP with 100 age- and sex-matched population controls. We assessed imaging biomarkers on MRI (calcaneal bone marrow lesions (BMLs), plantar fascia signal and thickness, spurs and fat pad signal) and B-mode/ power Doppler US (plantar fascia thickness, echogenicity and vascularity). Covariate data collected included demographics, disease history, clinical measures and physical activity by accelerometry. Data were analysed using multivariable conditional logistic regression.

RESULTS

Plantar calcaneal BML size (mm² , OR 1.03 (95% CI 1.02 to 1.05)), larger plantar spurs (>5mm, OR 2.15 (95% CI 1.13 to 4.10)), plantar fascia signal (penetrating > 50% of dorsoplantar width, OR 12.12 (95% CI 5.36 to 27.42)), plantar fascia thickness (mm, (MRI) OR 3.23 (95% CI 2.36 to 4.43), (US) OR 3.78 ( 95% CI 2.69 to 5.32) and echogenicity (diffusely hypoechoic OR 7.89 (95% CI 4.02 to 15.48), focally hypoechoic OR 24.92 (95% CI 9.60 to 64.69)) were independently associated with CPHP. Plantar fascia vascularity was uncommon, occurring exclusively in cases (cases with signal n=47(22%)) Combining imaging biomarkers into one model, plantar BMLs and plantar fascia imaging biomarkers, but not fat pad signal or heel spurs, were independently associated with CPHP.

CONCLUSION

Calcaneal BMLs and plantar fascia imaging biomarkers are associated with CPHP. Further research is required to understand whether these different markers represent distinct phenotypes of heel pain, and if so, whether there are specific treatment implications.

Chronic plantar heel pain modifies associations of ankle plantarflexor strength and body mass index with calcaneal bone density and microarchitecture

Chronic plantar heel pain (CPHP) is associated with calcaneal bone spurs, but its associations with other calcaneal bone features are unknown. This study therefore aimed to determine associations between having CPHP and bone density and microarchitecture of the calcaneus. We assessed 220 participants with CPHP and 100 age- and sex-matched population-based controls. Trabecular bone density, thickness, separation and number, BV/TV, and cortical density, thickness and area were measured using a Scanco Xtreme1 HR-pQCT scanner at a plantar and mid-calcaneal site. Clinical, physical activity and disease history data were also collected. Associations with bone outcomes were assessed using multivariable linear regression adjusting for age, sex, physical activity, BMI and ankle plantarflexor strength. We assessed for potential effect modification of CPHP on these covariates using interaction terms. There were univariable associations at the plantar calcaneus where higher trabecular bone density, BV/TV and thickness and lower trabecular separation were associated with CPHP. In multivariable models, having CPHP was not independently associated with any bone outcome, but modified associations of BMI and ankle plantarflexor strength with mid-calcaneal and plantar bone outcomes respectively. Beneficial associations of BMI with mid-calcaneal trabecular density (BMI-case interaction standardised X/unstandardised Y beta -10.8(mgHA/cm3) (se 4.6), thickness -0.002(mm) (se 0.001) and BV/TV -0.009(%) (se 0.004) were reduced in people with CPHP. Beneficial associations of ankle plantarflexor strength with plantar trabecular density (ankle plantarflexor strength -case interaction -11.9(mgHA/cm3) (se 4.4)), thickness -0.003(mm) (se 0.001), separation -0.003(mm) (se 0.001) and BV/TV -0.010(%) (se 0.004) were also reduced. CPHP may have consequences for calcaneal bone density and microarchitecture by modifying associations of BMI and ankle plantarflexor strength with calcaneal bone outcomes. The reasons for these case-control differences are uncertain but could include a bone response to entheseal stress, altered loading habits and/or pain mechanisms. Confirmation with longitudinal study is required.

Patterns and Predictors of Television Viewing and Computer Use Among Women Living in Socioeconomically Disadvantaged Neighborhoods: A Prospective Cohort Study

BACKGROUND

Socioeconomically disadvantaged women are at an increased risk of sedentary behaviors including television (TV) viewing and computer use, so identifying determinants of these behaviors is important.

METHODS

Women (n = 4349) self-reported weekly TV and computer time (in minutes per week), sociodemographic, and health data at 3 time points (2007-2013). Mixed-effect negative binomial regression was used to determine the baseline determinants of TV viewing and computer use over time, adjusting for confounders.

RESULTS

Over 5 years, median TV viewing decreased while median computer time increased. Cross-sectionally TV viewing was highest among participants classified as obese, with poorer health, current smokers, with lower education, not working, with no income, without partners and with no children and computer time was greater among younger women, living in urban areas, working full time, with higher education, without partners and with no children. Average computer time per year increased among those not working (7%), with lower education (5%), and with children (5%) but decreased among those with higher education (1%). However, no factors were associated with a change in TV viewing over time.

CONCLUSION

Among socioeconomically disadvantaged women, interventions aimed at preventing increases in computer time should consider women with lower education, not working, and with children in their design.

68Maternal exposure to PM2.5 from a severe smoke event and birth outcomes in Victoria, Australia

Background

The 2014 Hazelwood coal mine fire was an unprecedented six-week severe smoke event in the Latrobe Valley, southeastern Australia. We aimed to determine whether maternal exposure to fine particulate matter (PM2.5) attributable to the event was associated with adverse fetal growth or maturity, including birthweight, small for gestational age, term low birthweight or preterm birth.

Methods

A cohort of babies born within the affected region was defined used administrative perinatal data. Maternal average and peak PM2.5 was assigned to residential address at time of delivery using a chemical transport model. Maternal, infant, meteorological and temporal variables were included in final linear and log-binomial regression models.

Results

3,591 singleton livebirths were included; 763 were exposed in utero. Average PM2.5 exposure was 4.4 µg/m3 (IQR 2.1 µg/m3); average peak was 45.0 µg/m3 (IQR 35.1 µg/m3). No association between PM2.5 and fetal growth or maturity was observed. Gestational diabetes mellitus was an effect modifier in the relationship; babies of exposed gestational diabetic mothers were 97 grams heavier per 10 µg/m3 increase in average PM2.5 exposure (95%CI 74, 120 grams), compared to mothers without gestational diabetes.

Conclusions

Maternal PM2.5 exposure from a smoke event was not associated with adverse fetal growth or maturity. There was a trophic response amongst babies of mothers with gestational diabetes.

Key messages

Babies born to mothers with gestational diabetes may be more susceptible to the effects of smoke events on birthweight.

67Maternal Exposure to PM2.5 from a Coal Mine Fire is Associated with Gestational Diabetes Mellitus

Background

In 2014, the Hazelwood coal mine fire was an unprecedented six-week severe smoke event in the Latrobe Valley, southeastern Australia. We aimed to determine whether maternal exposure to fine particulate matter (PM2.5) attributable to coal mine fire smoke was associated with gestational diabetes mellitus (GDM), hypertensive disorders of pregnancy and abnormal placentation.

Methods

We defined a cohort of all births &gt;20 weeks in the Latrobe Valley from 1 March 2012 - 31 Dec 2015 utilising administrative perinatal data. Average and peak PM2.5 was assigned to residential address at delivery using a chemical transport model. Maternal, meteorological and temporal variables were included in final log-binomial regression models.

Results

3,612 singleton pregnancies were included; 766 were exposed to the smoke event. Average maternal PM2.5 exposure was 4.4 µg/m3 (IQR 2.1). Average peak PM2.5 exposure was 44.9 µg/m3 (IQR 35.0). An interquartile range increase in average and peak PM2.5 was associated with a 7% and 16% increased likelihood of GDM respectively (Average PM2.5 95%CI 1.03, 1.10; &lt;0.0001; Peak PM2.5 95%CI 1.09, 1.22; &lt;0.0001). No association for hypertensive disorders or abnormal placentation was observed.

Conclusions

This is the first study to examine obstetric complications relating to a discrete smoke event. These findings may guide the public health response to future similar events.

Key messages

Exposure to a smoke event was associated with an increased risk of GDM.

The public health implications may be substantial with a changing climate.

66Adverse birth outcomes associated with ambient air pollution at levels below air quality guidelines

Background

Gaps exist concerning the relationship between maternal exposure to air pollution and birth outcomes, including the importance of low-level exposure. We aimed to explore the association between maternal exposure to ambient nitrogen dioxide (NO2) and fine particulate matter (PM2.5) and selected birth outcomes in Victoria, Australia.

Methods

We included all births occurring in Victoria, Australia from 1st March 2012 to 31st December 2015 using routinely collected government data. Outcomes included birthweight, small for gestational age (SGA), term low birth weight (tLBW), large for gestational age, and spontaneous preterm birth. Annual ambient NO2 and PM2.5 was assigned to maternal residence at birth. Maternal, meteorological and temporal variables were included in final log-binomial models.

Results

There were 285,594 births. Average annual ambient NO2 exposure was 6.0 parts per billion (ppb, IQR 3.9 ppb) and PM2.5 was 6.9 µg/m3 (IQR 1.3). IQR increases in ambient NO2 and PM2.5 were associated with fetal growth restriction, including decrements in birth weight, increased risk of SGA and tLBW. Women with gestational diabetes and hypertensive disorders of pregnancy had greater decrements in birth weight associated with exposure.

Conclusions

Maternal exposure to low-level ambient air pollution at levels below national and international air quality guidelines was associated with fetal growth restriction.

Key messages

Exposure to low-level ambient air pollution was associated with fetal growth restriction and women with obstetric complications were more susceptible.

These findings may inform iterative revisions of air quality guidelines.

Associations of dietary patterns with bone density and fractures in adults: A systematic review and meta-analysis

BACKGROUND AND OBJECTIVES

Although nutrition is important to bone health, the impact of different dietary patterns on bone density and fracture is unclear. The aim of this study was to synthesise conflicting evidence from observational studies to determine associations of empirically derived dietary patterns with bone density and fracture in healthy adults.

METHOD

A systematic review (PROSPERO CRD42017071676) with meta-analysis where possible (for hip fracture) and otherwise with best-evidence synthesis.

RESULTS

Twenty-one studies were included in the best-evidence synthesis and four in the meta-analysis. Meta-analysis demonstrated a protective association between 'healthy' pattern score and hip fracture (risk ratio 0.73; 95% confidence interval: 0.56, 0.96; I2 = 95%) for highest compared to lowest 'healthy' pattern score category. In best-evidence synthesis, there was conflicting evidence for associations of both pattern scores with bone density at all sites and total fractures and for 'Western' score and hip fracture. No study reported detrimental effects of 'healthy' patterns, or beneficial effects of 'Western' patterns.

DISCUSSION

The results suggest that general practitioners promoting a 'healthy' dietary pattern is, at worst, unlikely to be detrimental for bone health and, at best, may reduce hip fracture.

Patterns and Predictors of Sitting among Women from Disad-Vantaged Neighbourhoods over Time: A 5-Year Prospective Cohort Study

Background: Our aim was to describe patterns of sitting over time and determine the sociodemographic predictors of sitting over time among women living in socioeconomically disadvantaged neighbourhoods. Methods: Women age between 18 and 45 years (mean = 34.4 ±8.1, n = 4349) reported their sitting time, sociodemographic (e.g., age), and health (e.g., body mass index) three times over 5 years. Linear mixed modelling was used to determine the predictors of change in sitting over time, adjusting for covariates. Results: Mean baseline sitting time was 40.9 h/week, decreasing to 40.1 h/week over five years. Greater sitting time was reported in participants ≤25 years of age, living with obesity, living in urban areas, self-reported poor/fair health, working full-time, with higher education, never married and with no children. Annually, the average sitting time decreased by 0.4 h/week (95% CI; -0.7 to -0.05) in women working full-time but increased by 0.1 h/week (95% CI; -0.2 to 0.6) who were not working. Similarly, annual sitting time decreased by 0.6 h/week (95% CI; -0.2 to 1.3) in women with no children but increased by 0.4 h/week (95% CI; -0.2 to 0.5) and 0.9 h/week (95% CI; 0.3 to 1.3) among those with two and three/more children, respectively. Conclusion: Among disadvantaged women, those not working and with two or more children may be at particular risk for increased sitting time and warrant further attention.

Longitudinal associations of dietary patterns with sociodemographic and lifestyle factors in older adults: the TASOAC study

BACKGROUND/OBJECTIVES

To derive dietary patterns and examine their longitudinal associations with sociodemographic and lifestyle factors in the Tasmanian Older Adult Cohort.

SUBJECTS/METHODS

This is a corrected analysis of a retracted paper. We followed 1098 adults aged ≥50 years for 5 years. Dietary intake was assessed using a validated food frequency questionnaire. Baseline dietary patterns were identified using exploratory factor analysis and scores at each time point calculated using the weighted sum score method. Associations of energy-adjusted dietary pattern scores with participant characteristics were assessed using linear mixed-effects models.

RESULTS

The four dietary patterns identified were: fruit and vegetable (vegetables, potatoes, fruits); animal protein (poultry, red meats, fish); snack (snacks, sweets, nuts); western (meat pies, hamburgers, pizzas). Fruit and vegetable pattern scores were lower in men and current smokers at baseline. Animal protein scores were lower in older and retired people but higher in men and smokers at baseline. The sex difference in animal protein score increased over time (p = 0.012). At baseline, snack score was positively associated with age and physical activity, but lower in men and current smokers. The effect of age on snack score lessened over time (p = 0.035). Western scores were lower in older people but higher in men, current smokers and those living in disadvantaged areas at baseline. The effect of age on western score reduced over time (p = 0.001).

CONCLUSIONS

The higher scores for healthy and/or lower scores for unhealthy patterns in men, smokers, retirees and those experiencing social disadvantage suggest these could be target groups for interventions to improve diet quality in older adults.

The association between socioeconomic status and joint replacement of the hip and knee: A population-based cohort study of older adults in Tasmania

BACKGROUND

A socioeconomic gradient exists in the utilisation of total hip replacements (THR) and total knee replacements (TKR) for osteoarthritis. However, the relations between socioeconomic status (SES) and time to THR or TKR is unknown.

AIM

To describe the association between SES and time to THR and TKR.

METHODS

1072 older-adults residing in Tasmania, Australia were studied. Incident primary THR and TKR were determined by data linkage to the Australian Orthopaedic Association National Joint Replacement Registry. At baseline, each participant's area-level SES was determined by the Index of Relative Socioeconomic Advantage and Disadvantage (IRSAD), from the Australian Bureau of Statistics' 2001 census data. IRSAD was analysed in two ways; 1) categorised into quartiles, whereby quartile 1 represented the most socioeconomically disadvantaged group, 2) the cohort dichotomised at the quartile 1 cut-point.

RESULTS

The mean age was 63.0 (±7.5) years, and 51% were women. Over the median follow-up of 12.9 (Interquartile range: 12.2-13.9) years, 56 (5%) participants had a THR, and 79 (7%) had a TKR. Compared to the most disadvantaged quartile, less disadvantaged participants were less likely to have a THR (i.e. less disadvantaged participants had a longer time to THR) (HR: 0.56, 95% CI 0.32, 1.00) but not TKR (HR: 0.90, 95% CI 0.53, 1.54). However, the former became non-significant after adjustment for pain and radiographic osteoarthritis, suggesting that the associations may be mediated by these factors.

CONCLUSIONS

This study suggests that time to joint replacement was determined according to the symptoms/need of the participants rather than their SES. This article is protected by copyright. All rights reserved.

Adverse birth outcomes in Victoria, Australia in association with maternal exposure to low levels of ambient air pollution

BACKGROUND

The relationship between maternal exposure to air pollution and birth outcomes is not well characterised where ambient air pollution is relatively low.

OBJECTIVES

We aimed to explore the association between maternal exposure to ambient nitrogen dioxide (NO₂) and fine particulate matter (PM_2.5) and a range of birth outcomes in Victoria, Australia. Secondary aims were to explore whether obstetric conditions, such as gestational diabetes mellitus (GDM) and hypertensive disorders of pregnancy, were effect modifiers in observed relationships.

METHODS

We included all singleton births occurring in Victoria, Australia from 1^st March 2012 to 31^st December 2015 using routinely collected government data. Outcomes included birth weight, small for gestational age (SGA), term low birth weight (tLBW), large for gestational age (LGA), and spontaneous preterm birth (sPTB). We estimated exposure to annual ambient NO₂ and PM_2.5 concentrations, assigned to maternal residence at time of birth. Confounders included maternal, meteorological and temporal variables. Multivariable linear regression and log-binomial regression were used for continuous and dichotomous outcomes, respectively.

RESULTS

There were 285,594 births during the study period. Average NO₂ exposure was 6.0 parts per billion (ppb, median 5.6; interquartile range (IQR) 3.9) and PM_2.5 was 6.9 μg/m³ (median 7.1, IQR 1.3). IQR increases in ambient NO₂ and PM_2.5 were associated with fetal growth restriction, including decrements in birth weight (NO₂ β -22.8 g; 95%CI -26.0, -19.7; PM_2.5 β -14.8 g; 95%CI -17.4, -12.2) and increased risk of SGA (NO₂ RR 1.08; 95%CI 1.06, 1.10; PM_2.5 RR 1.05; 95%CI 1.04, 1.07) and tLBW (NO₂ RR 1.06; 95%CI 1.01, 1.10; PM_2.5 RR 1.04; 95%CI 1.03, 1.08). Women with GDM and hypertensive disorders of pregnancy had greater decrements in birth weight in association with pollutant exposure.

DISCUSSION

In this exploratory study using an annual metric of exposure, maternal exposure to low-level ambient air pollution was associated with fetal growth restriction, which carries substantial public health implications.

Maternal exposure to fine particulate matter from a large coal mine fire is associated with gestational diabetes mellitus: A prospective cohort study

BACKGROUND

In 2014, the Hazelwood coal mine fire was an unprecedented event that resulted in a six-week period of poor air quality in the Latrobe Valley in regional Australia. We aimed to determine whether maternal exposure to fine particulate matter in coal mine fire smoke was associated with selected obstetric complications, including gestational diabetes mellitus, hypertensive disorders of pregnancy and abnormal placentation.

METHODS

We defined a complete cohort of pregnant women with births >20 weeks in the Latrobe Valley from March 1, 2012-Dec 31, 2015 utilising administrative perinatal data. Average and peak fine particulate matter (PM_2.5) was assigned to residential address at delivery using a chemical transport model. Maternal, meteorological and temporal variables were included in final log-binomial regression models.

RESULTS

3612 singleton pregnancies were included in the analysis; 766 were exposed to the smoke event. Average maternal PM_2.5 exposure was 4.4 μg/m³ (SD 7.7; IQR 2.12). Average peak PM_2.5 exposure was 44.9 μg/m³ (SD 57.1; IQR 35.0). An interquartile range increase in peak PM_2.5 was associated with a 16% increased likelihood of gestational diabetes mellitus (95%CI 1.09, 1.22; <0.0001). Whereas, an interquartile range increase in average PM_2.5 was associated with a 7% increased likelihood of gestational diabetes mellitus (95%CI 1.03, 1.10; <0.0001). Second trimester exposure was of critical importance. No association for hypertensive disorders or abnormal placentation was observed.

CONCLUSION

this is the first study to examine obstetric complications relating to a discrete smoke event. These findings may guide the public health response to future similar events.

Identifying subgroups of community-dwelling older adults and their prospective associations with long-term knee osteoarthritis outcomes

OBJECTIVES

To identify subgroups of community-dwelling older adults and to assess their longitudinal associations with long-term osteoarthritis (OA) outcomes.

METHODS

1046 older adults aged 50-80 years were studied. At baseline, body mass index (BMI), pedometer-measured ambulatory activity (AA), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) determined knee pain and information on comorbidities were obtained. Tibial cartilage volume and bone-marrow lesions (BMLs) were assessed using MRI at baseline and 10 years and total knee replacements (TKR) by data linkage to the Australian Orthopaedic Association National Joint Replacement Registry. Latent class analysis was used to determine participant subgroups, considering baseline BMI, AA, pain and comorbidities, and linear mixed-effects or log-binomial models were used to assess the associations.

RESULTS

Three subgroups/classes were identified: subgroup 1 (43%): Normal/overweight participants with higher AA, lower pain and lower comorbidities; subgroup 2 (32%): Overweight participants with lower AA, mild pain and higher comorbidities; subgroup 3 (25%): Obese participants with lower AA, mild pain and higher comorbidities. Subgroup 3 had greater cartilage volume loss (β - 60.56 mm³, 95% CI - 105.91, - 15.21) and a higher risk of TKR (RR 3.19, 95% CI 1.75, 5.81), compared to subgroup 1. Subgroup 2 was not associated with cartilage volume change (β 13.06 mm³, 95% CI - 30.87, 57.00) or risk of TKR (RR 1.16, 95% CI 0.56, 2.36), compared to subgroup 1. Subgroup membership was not associated with worsening BMLs.

CONCLUSIONS

Our findings suggest the existence of homogeneous subgroups of participants and support the utility of identifying patterns of characteristics/risk factors that may cluster together and using them to identify subgroups of people who may be at a higher risk of developing and/or progressing OA. Key Points • Complex interplay among characteristics/factors leads to conflicting evidence between ambulatory activity and knee osteoarthritis. • Distinct subgroups are identifiable based on ambulatory activity, body mass index, knee pain, and comorbidities. • Identifying subgroups can be used to determine those who are at risk of developing/progressing osteoarthritis.

Associations of health literacy with risk factors for diabetic foot disease: a cross-sectional analysis of the Southern Tasmanian Health Literacy and Foot Ulcer Development in Diabetes Mellitus Study

OBJECTIVES

Poor health literacy (HL) is associated with poorer health outcomes in diabetes but little is known about its effects on foot disease. This study was aimed to determine the associations between HL and diabetic foot disease.

DESIGN

This is a cross-sectional analysis of baseline data from a prospective study of foot disease.

SETTING

Attendees of the Royal Hobart Hospital's Diabetes outpatient clinics.

PARTICIPANTS

222 people with type 1 or type 2 diabetes aged >40 years and without a history of foot disease, psychotic disorders or dementia.

MEASURES

Outcomes were peripheral neuropathy, peripheral arterial disease and foot deformity according to published guidelines. The exposure, HL, was measured using the short form Test of Functional Health Literacy in Adults (S-TOFHLA) and the Health Literacy Questionnaire (HLQ). Covariates included demographic characteristics, medical history, psychological measures and foot care behaviour.

RESULTS

Of 222 participants, 204 had adequate HL. (Mean (SD) S-TOFHLA scores were 31.9 (6.7)), mean(SD) HLQ scores were 134.4 (18.4)). In univariable but not multivariable analyses, higher S-TOFHLA scores were associated with lower overall risk for foot disease (OR 0.96, 95% CI 0.93 to 0.99) and loss of protective sensation (OR 0.95, 95% CI 0.91 to 0.995).

CONCLUSIONS

These data provide little support for clinically important impacts of HL on risk factors for diabetic foot disease. However, in the absence of longitudinal data, such effects cannot be ruled out. Longitudinal studies measuring incident foot disease are needed to properly judge the potential for interventions improving HL to reduce the incidence of diabetic foot disease.

Maternal exposure to fine particulate matter from a coal mine fire and birth outcomes in Victoria, Australia

INTRODUCTION

The Hazelwood coal mine fire was an unprecedented event in Australian history that resulted in the surrounding towns in regional Victoria being covered in plumes of smoke and ash for six weeks in 2014. Evidence concerning adverse reproductive impacts associated with maternal exposure to ambient air pollution is expanding. Gaps remain regarding the relative impact of acute changes in outdoor air quality lasting days to months, such as that resulting from coal mine fires.

METHODS

Routinely collected perinatal data was used to define a complete cohort of singleton babies born within the affected region. Maternal average, and peak, fine particulate matter (PM_2.5) was assigned to residential address at time of delivery using a chemical transport model. Maternal, infant, meteorological and temporal variables were adjusted for in final linear and log-binomial regression models.

RESULTS

There were a total of 3591 singleton livebirths during the study period; 763 of which were in utero during the coal mine fire. Average PM_2.5 exposure was 4.4 μg/m³ (median 1.9; IQR 2.1 μg/m³) and peak was 45.0 μg/m³ (median 30.4; IQR 35.1 μg/m³). There was no association between coal mine fire-attributable PM_2.5 and fetal growth or gestational maturity outcomes. However, there was weak evidence that gestational diabetes mellitus was an effect modifier in the relationship between maternal PM_2.5 exposure and birth weight. Babies born to exposed gestational diabetic mothers were 97 g heavier per 10 μg/m³ increase in average PM_2.5 exposure (95%CI 74, 120 g). No association was observed among mothers without gestational diabetes.

CONCLUSION

Maternal exposure to fine particulate matter resulting from the 2014 Hazelwood coal mine fire did not appear to adversely effect fetal maturity. However, there was weak evidence of a trophic response among babies born to exposed mothers with gestational diabetes, a possible susceptibility that requires further exploration.

Patellar tendon enthesis abnormalities and their association with knee pain and structural abnormalities in older adults

OBJECTIVE

To describe associations between presence of patellar tendon enthesis (PTE) abnormalities and symptoms, structural abnormalities, and total knee replacement (TKR) in older adult cohort.

METHODS

PTE abnormalities (presence of abnormal bone signal and/or bone erosion), were measured on T2-weighted magnetic resonance (MR) images at baseline in 961 community-dwelling older adults. Knee pain and function limitation were assessed using Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Bone marrow lesions (BMLs), cartilage volume and defects score, and infrapatellar fat pad (IPFP) area were measured using validated methods. Incidence of TKR was determined by data linkage.

RESULTS

Participants with abnormal PTE bone signal and/or erosion was 20%. Cross-sectionally, presence of PTE abnormalities was associated with greater pain intensity while going up and down stairs (β = 0.22 (95% confidence interval (CI); 0.03, 0.41)), greater risk of femoral BMLs (RR = 1.46 (1.12, 1.90)) and worse tibial cartilage defects score (RR = 1.70 (1.16, 2.47), and smaller IPFP area (β = -0.27 (-0.47, -0.06) cm²), after adjustment of confounders. Longitudinally, presence of baseline PTE abnormalities was associated with a deleterious increase in tibial BML size (RR = 1.52 (1.12, 2.05)) over 10.7 years but not symptoms, other structural changes, or TKR.

CONCLUSION

PTE abnormalities are common in older adults. Presence of cross-sectional but not longitudinal associations suggests they are commonly co-exist with other knee structural abnormalities but may not play a major role in symptom development or structural change, excepting tibial BMLs.

Prospective associations of osteosarcopenia and osteodynapenia with incident fracture and mortality over 10 years in community-dwelling older adults

AIM

To determine whether older adults with low muscle mass (sarcopenia) and strength (dynapenia), in the presence of osteoporosis/osteopenia, have an increased risk of fracture and mortality over 10 years, compared to those with low muscle or low bone mass alone or with neither condition.

METHODS

1032 participants (52% women; mean age 62.9 ± 7.4 years) were prospectively followed for 10 years. Mortality was ascertained from the death registry and fractures were self-reported. Baseline appendicular lean mass (ALM) was assessed using dual-energy X-ray absorptiometry and normalised to body mass index (BMI). Hand grip strength (HGS) was assessed by dynamometer. Osteosarcopenia and osteodynapenia were defined as having T-scores of the total hip and/or lumbar spine bone mineral density (BMD) < -1 combined with being in the lowest 20% of the sex-specific distribution for ALM/BMI or HGS respectively.

RESULTS

Incident fracture risk was significantly higher in participants who were osteodynapenic (RR = 2.07, 95% CI: 1.26-3.39), dynapenic alone (RR = 1.74, 95% CI: 1.05-2.87), and osteopenic alone (RR = 1.63, 95% CI: 1.15-2.31), compared to those without dynapenia or osteopenia. Mortality risk was significantly higher only in participants with osteosarcopenia (RR = 1.49, 95% CI: 1.01-2.21) compared to those without sarcopenia or osteopenia. However, osteosarcopenia and osteodynapenia did not lead to a significantly greater fracture or mortality risk compared to having these conditions on their own.

CONCLUSION

These findings suggest that the combined effect of osteopenia and sarcopenia or dynapenia on fracture and mortality risk, respectively, may not be greater than that of each individual condition.

Prospective associations of low muscle mass and strength with health-related quality of life over 10-year in community-dwelling older adults

AIMS

This study aims to describe the associations of low muscle mass, handgrip (HGS) and lower-limb muscle strength (LMS) with health-related quality of life (HRQoL) over 10 years in community-dwelling older adults.

METHODS

Participants (N = 1002; 51% women; mean age 63 ± 7.4 years) were prospectively followed for 10 years. HRQoL was measured using the validated assessment of quality of life (AQoL) instrument. Appendicular lean mass (ALM) was assessed using dual energy X-ray absorptiometry and normalized to body mass index (BMI). HGS and LMS were assessed using dynamometers. Low ALM/BMI (ALM/BMI_LOW), LMS (LMS_LOW) and HGS (HGS_LOW) at baseline were defined as the lowest 20% of the sex-specific distribution for each measure. Linear mixed effect regression models, adjusting for confounders, were used to estimate the association between ALM/BMI_LOW, LMS_LOW, and HGS_LOW at baseline and HRQoL over 10 years.

RESULTS

Participants with LMS_LOW (β = -0.061, 95% CI: -0.089, -0.033) and women (β = -0.089, 95% CI: -0.129, -0.049) but not men (β = -0.023, 95% CI: -0.064, 0.019) with HGS_LOW had clinically meaningful reductions in HRQoL over 10 years compared to those with normal strength. There was a weaker but statistically significant association between ALM/BMI_LOW and 10-year HRQoL (β = -0.038, 95% CI: -0.068, -0.008).

CONCLUSIONS

Lower-limb muscle strength and handgrip strength (in women only), which can be easily measured in clinical practice, appear more important than muscle mass for HRQoL.

Maternal exposure to short-to medium-term outdoor air pollution and obstetric and neonatal outcomes: A systematic review

BACKGROUND

Little is known about the impacts of maternal exposure to acute episodes of outdoor air pollution, such as that resulting from wildfires, on obstetric and neonatal outcomes. This systematic review aims to synthesise the existing literature exploring the relationship between maternal exposure to short-to medium-term changes in outdoor air quality and obstetric and neonatal outcomes.

METHODS

A systematic search of peer-reviewed articles using PubMed, Cochrane Library, EMBASE, ScienceDirect, Web of Science, ProQuest, GreenFILE and Scopus was conducted in January 2018 using selected search terms. Quality of included studies were assessed using the Newcastle Ottawa Scale.

RESULTS

Eleven studies were included; eight assessed the impact of maternal exposure to air pollution exacerbation events, such as wildfires, oil well fires and volcanic eruptions, and three assessed the impact of improvement events, such as the 2018 Beijing Olympics and closure of industrial activities, on obstetric and neonatal outcomes. Studies were highly heterogenous in methodology. Six studies found a significant association between acute changes in air quality and markers of fetal growth restriction, while two did not. Three studies found an adverse association between acute changes in air quality and markers of gestational maturity, and one did not.

CONCLUSION

Overall, there is some evidence that maternal exposure to acute changes in air quality of short-to medium-term duration increases the risk of fetal growth restriction and preterm birth. The relationship for other adverse obstetric or neonatal outcomes is less clear.

Associations of health literacy with diabetic foot outcomes: a systematic review and meta-analysis

BACKGROUND

People with diabetes have low health literacy, but the role of the latter in diabetic foot disease is unclear.

AIM

To determine, through a systematic review and meta-analysis, if health literacy is associated with diabetic foot disease, its risk factors, or foot care.

METHODS

We searched PubMed, EMBASE, CINAHL, Web of Science, Scopus and Science Direct. All studies were screened and data extracted by two independent reviewers. Studies in English with valid and reliable measures of health literacy and published tests of association were included. Data were extracted on the associations between the outcomes and health literacy. Meta-analyses were performed using random effects models.

RESULTS

Sixteen articles were included in the systematic review, with 11 in the meta-analysis. In people with inadequate health literacy, the odds of having diabetic foot disease were twice those in people with adequate health literacy, but this was not statistically significant [odds ratio 1.99 (95% CI 0.83, 4.78); two studies in 1278 participants]. There was no statistically significant difference in health literacy levels between people with and without peripheral neuropathy [standardized mean difference -0.14 (95% CI -0.47, 0.18); two studies in 399 participants]. There was no association between health literacy and foot care [correlation coefficient 0.01 (95% CI -0.07, 0.10); seven studies in 1033 participants].

CONCLUSIONS

There were insufficient data to exclude associations between health literacy and diabetic foot disease and its risk factors, but health literacy appears unlikely to have a role in foot care. The contribution of low health literacy to diabetic foot disease requires definitive assessment through robust longitudinal studies.

Favourable outcomes for childhood acute lymphoblastic leukaemia in an isolated setting: The Tasmanian experience

BACKGROUND

Tasmania is a large, relatively isolated island located south of mainland Australia with limited tertiary level paediatric oncology services.

AIMS

To benchmark regional outcomes for childhood acute lymphoblastic leukaemia (ALL) against published international standards.

METHODS

We undertook a retrospective cohort study, analysing the clinical characteristics and health outcomes of all children diagnosed with and treated for ALL in Tasmania, Australia between 2006 and 2015.

RESULTS

Thirty-five patients aged less than 18 years were diagnosed with ALL in the study's 10-year period. Twenty-eight cases were precursor B cell in origin, with 7 cases of T-cell ALL. The great majority of children (30/35; 86%) received their entire first line treatment in Tasmania. Major treatment-related toxicities, including allergic drug reactions, and episodes of acute pancreatitis, deep venous thrombosis and bacterial sepsis, were managed locally, with one death secondary to overwhelming infection and multiorgan failure. The overall and event-free survival rates for childhood ALL were 30/35 (86%) and 28/35 (80%), respectively.

CONCLUSIONS

These results compare favourably with published results from large international cooperative group trials based in developed countries. Continued local treatment with appropriate support from a dedicated specialist paediatric oncology unit is therefore justified.

How Do MRI-Detected Subchondral Bone Marrow Lesions (BMLs) on Two Different MRI Sequences Correlate with Clinically Important Outcomes?

The aim of this study is to describe the association of bone marrow lesions (BMLs) present on two different MRI sequences with clinical outcomes, cartilage defect progression, cartilage volume loss over 2.7 years, and total knee replacement (TKR) over 13.3 years. 394 participants (50-80 years) were assessed at baseline and 2.7 years. BML presence at baseline was scored on T1-weighted fat-suppressed 3D gradient-recalled acquisition (T1) and T2-weighted fat-suppressed 2D fast spin-echo (T2) sequences. Knee pain, function, and stiffness were assessed using WOMAC. Cartilage volume and defects were assessed using validated methods. Incident TKR was determined by data linkage. BMLs were mostly present on both MRI sequences (86%). BMLs present on T2, T1, and both sequences were associated with greater knee pain and functional limitation (odds ratio = 1.49 to 1.70; all p < 0.05). Longitudinally, BMLs present on T2, T1, and both sequences were associated with worsening knee pain (β = 1.12 to 1.37, respectively; p < 0.05) and worsening stiffness (β = 0.45 to 0.52, respectively; all p < 0.05) but not worsening functional limitation or total WOMAC. BMLs present on T2, T1, and both sequences predicted site-specific cartilage defect progression (relative risk = 1.22 to 4.63; all p < 0.05) except at the medial tibial and inferior patellar sites. Lateral tibial and superior patellar BMLs present on T2, T1, and both sequences predicted site-specific cartilage volume loss (β = - 174.77 to - 140.67; p < 0.05). BMLs present on T2, T1, and both sequences were strongly associated with incident TKR. BMLs can be assessed on either T2- or T1-weighted sequences with no clinical predictive advantage of either sequence.

The association between ambulatory activity, body composition and hip or knee joint replacement due to osteoarthritis: a prospective cohort study

OBJECTIVE

To examine the association between ambulatory activity (AA), body composition measures and hip or knee joint replacement (JR) due to osteoarthritis.

DESIGN

At baseline, 1082 community-dwelling older-adults aged 50-80 years were studied. AA was measured objectively using pedometer and body composition by dual-energy X-ray absorptiometry. The incidence of primary (first-time) JR was determined by data linkage to the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR). Log binomial regression with generalized estimating equations were used to estimate the risk of JR associated with baseline AA and body composition measures, adjusting for age, sex, X-ray disease severity, and pain.

RESULTS

Over 13 years of follow-up, 74 (6.8%) participants had a knee replacement (KR) and 50 (4.7%) a hip replacement (HR). AA was associated with a higher risk of KR (RR 1.09/1000 steps/day, 95% CI 1.01, 1.16) and a lower risk of HR (RR 0.90/1000 steps/day, 95% CI 0.81, 0.99). Body mass index (BMI) (RR 1.07/kg/m², 95% CI 1.03, 1.12), total fat mass (RR 1.03/kg, 95% CI 1.01, 1.06), trunk fat mass (RR 1.05/kg, 95% CI 1.00, 1.09), and waist circumference (RR 1.02/cm, 95% CI 1.00, 1.04) were associated with a higher risk of KR. Body composition measures were not associated with HR.

CONCLUSIONS

An objective measure of AA was associated with a small increased risk of KR and a small reduced risk of HR. Worse body composition profiles were associated with KR, but not HR. Altogether this may suggest different causal pathways for each site with regard to habitual activity and obesity.

Low intensity repetitive transcranial magnetic stimulation modulates skilled motor learning in adult mice

Repetitive transcranial magnetic stimulation (rTMS) is commonly used to modulate cortical plasticity in clinical and non-clinical populations. Clinically, rTMS is delivered to targeted regions of the cortex at high intensities (>1 T). We have previously shown that even at low intensities, rTMS induces structural and molecular plasticity in the rodent cortex. To determine whether low intensity rTMS (LI-rTMS) alters behavioural performance, daily intermittent theta burst LI-rTMS (120 mT) or sham was delivered as a priming or consolidating stimulus to mice completing 10 consecutive days of skilled reaching training. Relative to sham, priming LI-rTMS (before each training session), increased skill accuracy (~9%) but did not alter the rate of learning over time. In contrast, consolidating LI-rTMS (after each training session), resulted in a small increase in the rate of learning (an additional ~1.6% each day) but did not alter the daily skill accuracy. Changes in behaviour with LI-rTMS were not accompanied with long lasting changes in brain-derived neurotrophic factor (BDNF) expression or in the expression of plasticity markers at excitatory and inhibitory synapses for either priming or consolidation groups. These results suggest that LI-rTMS can alter specific aspects of skilled motor learning in a manner dependent on the timing of intervention.

Longitudinal associations between serum 25-hydroxyvitamin D, physical activity, knee pain and dysfunction and physiological falls risk in community-dwelling older adults

AIMS

To describe the longitudinal associations between physiological falls risk, and between-person and within-person effects of 25-hydroxyvitamin D (25OHD), physical activity (PA), knee pain and dysfunction in community-dwelling older people.

METHODS

Data for 1053 participants (51% women; mean age 63 ± 7.4 years) studied at baseline, 2.5, 5, and 10 years were analysed. Falls risk (Z-score) was measured using the Physiological Profile Assessment. Knee pain and dysfunction were assessed using the Western Ontario and McMaster Universities Osteoarthritis index (WOMAC). Moderate-to-vigorous PA (MVPA) was measured using accelerometer. Linear mixed-effect regression models, with adjustment for confounders, were used to estimate the association between physiological falls risk and between-person and within-person effects of PA, 25OHD and WOMAC score.

RESULTS

Between-person effects showed that 10-year average physiological falls risk was lower in participants who had a higher 10-year average 25OHD (β = -0.005 per nmol/l, 95% CI: -0.008, -0.002), log-MVPA (β = -0.16 per minute, 95% CI: -0.22, -0.10) and lower mean WOMAC score (β = 0.005 per-unit score, 95% CI: 0.003, 0.01). Within-person effects showed that a higher physiological falls risk at any time-point was associated with higher than average WOMAC score (β = 0.002 per-unit score, 95% CI: 0.0003, 0.004) and lower than average log-MVPA (β = -0.15 per minute, 95% CI: -0.24, -0.06), but not 25OHD, at the same time-point.

CONCLUSION

Having higher WOMAC global score above an individual's average increases the risk of falling, whereas, increasing one's own MVPA level further reduces their risk of falling. The presence of between-person but not within-person associations for 25OHD suggests the former may be confounded by other factors.

Individualized Fracture Risk Feedback and Long-term Benefits After 10 Years

INTRODUCTION

This study aimed to determine if beneficial effects of individualized feedback of fracture risk on osteoporosis preventive behaviors and bone mineral density observed in a 2-year trial were sustained long-term.

METHODS

This was a 10-year follow-up of a 2-year RCT in 470 premenopausal women aged 25-44 years, who were randomized to one of two educational interventions (the Osteoporosis Prevention and Self-Management Course [OPSMC] or an osteoporosis information leaflet) and received tailored feedback of their relative risk of fracture in later life (high versus normal risk groups). Bone mineral density of lumbar spine and femoral neck were measured by dual-energy X-ray absorptiometry. Physical activity, dietary calcium intake, calcium and vitamin D supplements, and smoking status were measured by questionnaires.

RESULTS

From 2 to 12 years, the high-risk group had a smaller decrease in femoral neck bone mineral density (β=0.023, 95% CI=0.005, 0.041 g/cm²) but similar lumbar spine bone mineral density change as the normal-risk group. They were more likely to use calcium (relative risk=1.66, 95% CI=1.22, 2.24) and vitamin D supplements (1.99, 95% CI=1.27, 3.11). The OPSMC had no effects on bone mineral density change. Both high-risk (versus normal-risk) and the OPSMC groups (versus leaflet) had a more favorable pattern of smoking behavior change (relative risk=1.85, 95% CI=0.70, 4.89 and relative risk=2.27, 95% CI=0.86, 6.01 for smoking cessation; relative risk=0.33, 95% CI=0.13, 0.80 and relative risk=0.28, 95% CI=0.10, 0.79 for commenced or persistent smoking).

CONCLUSIONS

Feedback of high fracture risk to younger women was associated with long-term improvements in osteoporosis preventive behaviors and attenuated femoral neck bone mineral density loss. Therefore, this could be considered as a strategy to prevent osteoporosis.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ANZCTR) NCT00273260.

Both Baseline and Change in Lower Limb Muscle Strength in Younger Women Are Independent Predictors of Balance in Middle Age: A 12-Year Population-Based Prospective Study

Poor balance is a risk factor for falls and fracture in older adults, but little is known about modifiable factors affecting balance in younger women. This study aimed to examine whether lower limb muscle strength (LMS) in young women and changes in LMS are independent predictors of balance in middle age. This was an observational 10-year follow-up of 470 women aged 25 to 44 years at baseline who had previously participated in a 2-year population-based randomized controlled trial of osteoporosis education interventions. Linear regression was used to examine the association between baseline LMS (by dynamometer) and change in LMS over 12 years with balance at 12 years (timed up and go test [TUG], step test [ST], functional reach test [FRT], and lateral reach test [LRT]). LMS declined by a mean of 17.3 kg over 12 years. After adjustment for potential confounders, baseline and change in LMS were independently beneficially associated with TUG (β = -0.008 sec/kg, 95% confidence interval [CI] -0.01 to -0.006, and β = -0.006 sec/kg, 95% CI -0.009 to -0.003 for baseline and change, respectively), FRT (β = 0.057 cm/kg, 95% CI 0.030 to 0.084, and β = 0.071 cm/kg, 95% CI 0.042 to 0.101, respectively), and LRT (β = 0.030 cm/kg, 95% CI 0.012 to 0.049, and β = 0.022 cm/kg, 95% CI 0.002 to 0.043, respectively) 12 years later. There was an association between baseline LMS and ST (β = 0.044 steps/kg, 95% CI 0.022 to 0.067) but not between change in LMS and ST. Among young women, greater LMS at baseline and slower decline over time are both associated with better balance in midlife. Analogous to the contributions of peak bone mass and bone loss to fracture risk in older adults, this suggests that both improvement of muscle strength in younger age and prevention of age-related loss of muscle strength could be potentially useful strategies to improve balance and reduce falls in later life. © 2017 American Society for Bone and Mineral Research.

Moderate-to-Vigorous Physical Activity But Not Sedentary Time Is Associated With Musculoskeletal Health Outcomes in a Cohort of Australian Middle-Aged Women

Associations between physical activity and time spent sedentary and musculoskeletal outcomes remain unclear in middle-aged adults. This study aimed to describe associations between objectively-measured physical activity and sedentary time and musculoskeletal health outcomes in middle-aged women. This cross-sectional study from a population-based sample of 309 women (age 36 to 57 years) examined associations of total physical activity (accelerometer counts/min of wear time), and time spent sedentary, in light physical activities and moderate-to-vigorous physical activities (MVPA) (by Actigraph GT1M accelerometer) with lumbar spine (LS) and femoral neck (FN) bone mineral density (BMD) (by dual-energy X-ray absorptiometry), lower limb muscle strength (LMS), and functional mobility and balance tests (timed up and go test [TUG], functional reach test [FRT], lateral reach test [LRT], and step test [ST]) using linear regression. Total physical activity was beneficially associated with FN BMD (values are β; 95% CI) (0.011 g/cm² ; 95% CI, 0.003 to 0.019 g/cm² ), LMS (2.13 kg; 95% CI, 0.21 to 4.06 kg), and TUG (-0.080 s; 95% CI, -0.129 to -0.030 s), after adjustment for confounders. MVPA was also beneficially associated with FN BMD (0.0050 g/cm² ; 95% CI, 0.0007 to 0.0094 g/cm² ), LMS (1.48 kg; 95% CI, 0.45 to 2.52 kg), ST (0.12 steps; 95% CI, 0.02 to 0.23 steps), and TUG (-0.043 s; 95% CI, -0.070 to -0.016 s). Associations between MVPA and LMS, TUG and ST persisted after further adjustment for sedentary time. Only TUG was associated with sedentary time, with a detrimental effect (0.075 s; 95% CI, 0.013 to 0.137 s) and this did not persist after further adjustment for MVPA. Light physical activity was not associated with any outcome. MVPA appears more important than light physical activity or sedentary time for many musculoskeletal outcomes in middle-aged women. This needs to be considered when developing interventions to improve habitual physical activity that aim to improve musculoskeletal health. © 2016 American Society for Bone and Mineral Research.

Cut-points for associations between vitamin D status and multiple musculoskeletal outcomes in middle-aged women

This was the first study examining optimal vitamin D status for musculoskeletal health in middle-aged women. A 25-hydroxyvitamin D level of at least 29 to 33 nmol/L appears required for optimal musculoskeletal health, but the current cut-off of 50 nmol/L may be warranted.

INTRODUCTION

This study aimed to determine whether cut-points exist for associations between serum 25-hydroxyvitamin D (25OHD) and musculoskeletal health outcomes in middle-aged women, below which greater 25OHD levels are associated with musculoskeletal health benefits and above which no such associations exist.

METHODS

This is a cross-sectional study of 344 women aged 36-57 years. Cut-points for associations of serum 25OHD with lumbar spine (LS) and femoral neck (FN) bone mineral density (BMD), lower limb muscle strength (LMS), timed up and go test (TUG), functional reach test (FRT), lateral reach test (LRT), and step test (ST) were explored using locally weighted regression smoothing and nonlinear least-squares estimation, and associations above and below the identified cut-points were estimated using segmented regression.

RESULTS

The prevalence of low 25OHD was 28 % (<50 nmol/L). Significant cut-points (nmol/L) were identified for FN BMD 31 (95 % confidence interval (CI): 18, 43), LS BMD 31 (17, 45), TUG 30 (24, 36), ST 33 (24, 31), FRT 31 (18, 43), and LMS 29 (8, 49) but not LRT (42 (-8, 93). Below these cut-points, there were beneficial associations between higher 25OHD level and each outcome, while above the cut-points, there were no beneficial associations.

CONCLUSIONS

In middle-aged women, there are thresholds for associations between serum 25OHD concentrations and bone density and most balance measures, suggesting that 25OHD levels of at least 29 to 33 nmol/L are required for optimal musculoskeletal health in this population. The current cut-off of 50 nmol/L may be higher than needed for some outcomes but appears warranted overall.

Prospective Associations of Low Muscle Mass and Function with 10-Year Falls Risk, Incident Fracture and Mortality in Community-Dwelling Older Adults

OBJECTIVES

Purpose: To compare the performance of low muscle mass and function with falls risk, incident fracture and mortality over 10 years.

METHODS

1041 participants (50% women; mean age 63±7.5 years) were prospectively followed for 10 years. Falls risk was measured using the Physiological Profile Assessment, fractures were self-reported and mortality was ascertained from the death registry. Appendicular lean mass (ALM) was assessed using dual energy X-ray absorptiometry. Four anthropometric: (ALM/height2, ALM/body mass index, ALM/weight×100, a residuals method of ALM on height and total body fat) and four performance-based measures: (handgrip strength, lower-limb muscle strength, upper and lower-limb muscle quality) were examined. Participants in the lowest 20% of the sex-specific distribution for each anthropometric and performance-based measure were classified has having low muscle mass or function. Regression analyses were used to estimate associations between each anthropometric and performance-based measure at baseline and 10-year falls risk, incident fractures and mortality.

RESULTS

Mean falls risk z-score at 10 years was 0.64 (SD 1.12), incident fractures and mortality over 10 years were 16% and 14% respectively. All baseline performance-based measures were significantly associated with higher falls risk score at 10 years. Low handgrip (RR 1.55, 95% CI: 1.09, 2.20) and ALM/body mass index (RR 1.54, 95% CI: 1.14, 2.08) were the only significant predictors of fracture and mortality respectively.

CONCLUSIONS

Low handgrip strength, a simple and inexpensive test could be considered in clinical settings for identifying future falls and fractures. ALM/ body mass index could be most suitable in estimating 10-year mortality risk, but requires specialised equipment.

Prospective outcomes in patients with acute exacerbations of chronic obstructive pulmonary disease presenting to hospital: a generalisable clinical audit

BACKGROUND AND AIM

To determine predictors of short- and long-term outcomes in patients with acute exacerbation of chronic obstructive pulmonary disease (COPD) (AECOPD) presenting to hospital.

METHODS

A prospective clinical audit of AECOPD attendances to the only public acute general hospital in Southern Tasmania, Australia. Out of 416 attendances with AECOPD to the emergency department (ED) between November 2006 and July 2008, 150 patients with 218 attendances were followed to March 2009. Predictors of hospital admission from ED, in-hospital death, length of hospital stay, post-discharge mortality and re-attendance rate for AECOPD were the main outcomes.

RESULTS

There were no clear differences between patients admitted to hospital and those sent home from ED. Predictors of in-hospital death were initial physiologic parameters, that is, arterial pH, PaCO2 , oxygen saturation and blood pressure. Longer hospital stay was associated with older age, current smoking, hyperglycaemia, lower blood pressure and lower oxygen saturation. Risk of mortality after discharge was associated with a history of myocardial infarction, nursing home residence and severity of COPD. Re-attendance rate was associated with osteoporosis, younger age and severity of COPD.

CONCLUSIONS

Further investigation into the process of decision making about which AECOPD patients are admitted from the ED is required. Short-term outcomes, in-hospital death and length of hospital stay are mainly predicted by severity of the acute exacerbation and patient demographics. Although severity of COPD was a predictor of long-term outcomes, the main predictors of these were presence of co-morbidities.

Lower limb muscle strength is associated with poor balance in middle-aged women: linear and nonlinear analyses

This was the first study investigating both linear associations between lower limb muscle strength and balance in middle-aged women and the potential for thresholds for the associations. There was strong evidence that even in middle-aged women, poorer LMS was associated with reduced balance. However, no evidence was found for thresholds.

INTRODUCTION

Decline in balance begins in middle age, yet, the role of muscle strength in balance is rarely examined in this age group. We aimed to determine the association between lower limb muscle strength (LMS) and balance in middle-aged women and investigate whether cut-points of LMS exist that might identify women at risk of poorer balance.

METHODS

Cross-sectional analysis of 345 women aged 36-57 years was done. Associations between LMS and balance tests (timed up and go (TUG), step test (ST), functional reach test (FRT), and lateral reach test (LRT)) were assessed using linear regression. Nonlinear associations were explored using locally weighted regression smoothing (LOWESS) and potential cut-points identified using nonlinear least-squares estimation. Segmented regression was used to estimate associations above and below the identified cut-points.

RESULTS

Weaker LMS was associated with poorer performance on the TUG (β -0.008 (95 % CI: -0.010, -0.005) second/kg), ST (β 0.031 (0.011, 0.051) step/kg), FRT (β 0.071 (0.047, 0.096) cm/kg), and LRT (β 0.028 (0.011, 0.044) cm/kg), independent of confounders. Potential nonlinear associations were evident from LOWESS results; significant cut-points of LMS were identified for all balance tests (29-50 kg). However, excepting ST, cut-points did not persist after excluding potentially influential data points.

CONCLUSIONS

In middle-aged women, poorer LMS is associated with reduced balance. Therefore, improving muscle strength in middle-age may be a useful strategy to improve balance and reduce falls risk in later life. Middle-aged women with low muscle strength may be an effective target group for future randomized controlled trials.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ANZCTR) NCT00273260.

Cumulative risks and cessation of exclusive breast feeding: Australian cross-sectional survey

OBJECTIVES

To estimate the prevalence of cessation of exclusive breast feeding at each month up to 6 months and document key factors and cumulative risks associated with exclusive breastfeeding cessation for children aged from 0 to 6 months.

METHODS

Secondary analysis using a national representative sample of 22 202 mother and infant pairs derived from the 2010 Australian Institute of Health and Welfare cross-sectional survey, the Australian Infant Feeding Survey.

RESULTS

Among breastfed infants, 49% had ceased exclusive breast feeding before they had reached 2 months of age. In the final Cox proportional hazards model, cessation of exclusive breast feeding was most strongly associated with partners preferring bottle feeding (HR 1.86, 95% CI 1.69 to 20.6) or having no preference (HR 1.37, 95% CI 1.33 to 1.42), regular dummy use (HR 1.35, 95% CI 1.31 to 1.39) and maternal obesity (HR 1.29, 95% CI 1.24 to 1.35). Living within the most disadvantaged areas of Australia (quintile 1) was not strongly associated with cessation (HR 1.08, 95% CI 1.02 to 1.14) compared with least disadvantaged areas. Having three risk factors significantly increased the risk of cessation by 31% (HR 1.31, 95% CI 1.07 to 1.6).

CONCLUSIONS

The prevalence of early cessation of exclusive breast feeding is alarmingly high with 50% of infants no longer exclusively breast fed by age 2 months. Given that not one factor is associated with cessation of exclusive breast feeding, the greatest public health impact is likely to be achieved when multiple risk factors are modified or prevented.