A pilot randomized controlled trial evaluating outdoor community walking for knee osteoarthritis: walk

OBJECTIVES

To determine the feasibility of a randomized controlled trial (RCT) examining outdoor walking on knee osteoarthritis (KOA) clinical outcomes and magnetic resonance imaging (MRI) structural changes.

METHOD

This was a 24-week parallel two-arm pilot RCT in Tasmania, Australia. KOA participants were randomized to either a walking plus usual care group or a usual care control group. The walking group trained 3 days/week. The primary outcome was feasibility assessed by changes being required to the study design, recruitment, randomization, program adherence, safety, and retention. Exploratory outcomes were changes in symptoms, physical performance/activity, and MRI measures.

RESULTS

Forty participants (mean age 66 years (SD 1.4) and 60% female) were randomized to walking (n = 24) or usual care (n = 16). Simple randomization resulted in a difference in numbers randomized to the two groups. During the study, class sizes were reduced from 10 to 8 participants to improve supervision, and exclusion criteria were added to facilitate program adherence. In the walking group, total program adherence was 70.0% and retention 70.8% at 24 weeks. The walking group had a higher number of mild adverse events and experienced clinically important improvements in symptoms (e.g., visual analogue scale (VAS) knee pain change in the walking group: - 38.7 mm [95% CI - 47.1 to - 30.3] versus usual care group: 4.3 mm [- 4.9 to 13.4]).

CONCLUSIONS

This study supports the feasibility of a full-scale RCT given acceptable adherence, retention, randomization, and safety, and recruitment challenges have been identified. Large symptomatic benefits support the clinical usefulness of a subsequent trial.

TRIAL REGISTRATION NUMBER

12618001097235. Key Points • This pilot study is the first to investigate the effects of an outdoor walking program on knee osteoarthritis clinical outcomes and MRI joint structure, and it indicates that a full-scale RCT is feasible. • The outdoor walking program (plus usual care) resulted in large improvements in self-reported knee osteoarthritis symptoms compared to usual care alone. • The study identified recruitment challenges, and the manuscript explores these in more details and provides recommendations for future studies.

AB0994 Exploring knee osteoarthritis pain trajectories and movement-evoked pain changes during a 24-week outdoor walking program (WALK)

Background

Exercise therapy is recommended as first line treatment for knee osteoarthritis (OA), but it remains to be sub-optimally applied (1). Movement-evoked pain is a potential barrier to exercise adherence, but recent evidence suggests that such pain can be improved by training (2). Walking programs are low-cost, easily adopted and can be performed outdoors which can minimize the risk of SARS-CoV-2 transmission when in a group (3).

Objectives

To explore the acute pain trajectories of individuals with knee OA during a 24-week outdoor walking intervention. In addition, to explore the effect of pain trajectories and/or baseline characteristics on retention and adherence.

Methods

Individuals with clinical knee OA and bone marrow lesions (BMLs) on magnetic resonance imaging (MRI) were asked to follow a 24-week walking program. Every week consisted of two one hour supervised group sessions at various outdoor locations and one unsupervised session. At the start and end of every supervised group walk, knee pain was self-reported by participants to their trainer using a numerical rating scale (NRS) (0-10). The difference between the NRS pain values was considered as an acute pain change evoked by that walk. At baseline, the most affected knee of each participant was assessed using the Visual Analogue Scale (VAS) pain, the Western Ontario and McMasters Universities Osteoarthritis Index (WOMAC) pain, stiffness and function, wellbeing (3 questionnaires) and the Osteoarthritis Research Society International (OARSI) recommended strength and performance measures.

Results

In total, N = 24 participants started the program of whom N = 7 (29%) withdrew. Pain at the start of each walk decreased from NRS 2.5 (SD 1.6) at the first walk (N = 24) to NRS 0.9 (SD 0.8) at the final walk (N = 17). This pain was estimated to decrease on NRS by -0.04 (95% CI -0.05 to -0.02) per supervised session, p < 0.001 during the first 12 weeks and -0.01 (95% CI -0.02 to -0.004), p = 0.004 during the second twelve weeks of the program. The number (%) of participants who experienced an acute increase in pain decreased from 11 (45.8%) at the first walk to 4 (23.5%) at the last walk.

At baseline, non-adherent participants (<70% of group sessions) (N = 11) had lower physical performance scores, including the 30s Chair Stand Test (mean 10 (SD 1.7) stands versus mean 12.0 (SD 1.7) stands, p = 0.011), Fast Past Walk Test (1.23 (SD 0.14) meter per seconds (m/s) vs 1.50 (SD 0.20) m/s, p = 0.001), Six Minute Walk Test (418.8 (SD 75.9) m vs 529 (SD 72.6) m, p = 0.002), compared to adherent participants (N = 13). Non-adherent participants also had less severe self-reported symptoms including WOMAC stiffness (90.7 (SD 44.5) mm vs 121.5 (SD 17.0) mm, p = 0.031), compared to adherent participants. During the first two weeks of walking, acute increases in pain on average (mean ≥0.5 NRS) were reported by a greater number of non-adherent (N = 5 (45.5%)) than adherent participants (n = 4 (30.8%)).

Conclusion

This was an exploratory study and results need to be interpreted with caution due to the small sample size. The walking program resulted in clinically important improvements (MCIIs) (≥ 1 on NRS) (4) in start pain and acute pain changes. Improvements in start pain during the first 12-weeks were comparable to improvements measured in the NEMEX program (2) and may suggest that 12 weeks of exercise is sufficient to achieve MCIIs in pain. Improvements in acute changes in pain were smaller, which may have been related to a floor effect (5). Lower physical performance scores at baseline and more acute increases in pain during the first two weeks was associated with non-adherence. Participants with these characteristics may benefit from a lighter introduction to exercise.

References

[1]Bennell KL, et al. The Lancet Regional Health-Western Pacific. 2021;12:100187.

[2]Sandal LF, et al. Osteoarthritis and cartilage. 2016;24(4):589-92.

[3]Bulfone TC, et al. The Journal of infectious diseases. 2021;223(4):550-61.

[4]Perrot S, et al. Pain. 2013;154(2):248-56.

[5]McHorney CA, et al. Quality of life research. 1995;4(4):293-307.

Acknowledgements

We thank the participants who made this study possible. We would like to acknowledge the research staff, Kate Probert, Lizzy Reid, Simone Fitzgerald, Claire Roberts, Jasmin Ritchie, Dawn Simpson, and Tim Albion. We also thank Hamish Newsham-West for his contribution to the study design.

Disclosure of Interests

Stan Drummen: None declared, Saliu Balogun: None declared, Lieke Scheepers Grant/research support from: Competitive Grant Program Inflammation ASPIRE 2020 Rheumatology International Developed Markets from Pfizer, Employee of: previously worked as an Associate Director Epidemiology at the Medical Evidence Observational Research Department at AstraZeneca., Ishanka Munugoda: None declared, aroub lahham: None declared, Kim Bennell: None declared, Rana Hinman: None declared, Michele Callisaya: None declared, Guoqi Cai: None declared, Petr Otahal: None declared, Tania Winzenberg Consultant of: received payment to create educational material by AMGEN, Zhiqiang Wang: None declared, Benny Antony: None declared, Johanne Martel-Pelletier Shareholder of: ArthroLab Inc., Jean-Pierre Pelletier Shareholder of: ArthroLab Inc., François Abram Consultant of: ArthroLab Inc., Employee of: Arthrolab Inc., Graeme Jones Speakers bureau: received payment for a speakers bureau from Novartis, Dawn Aitken: None declared

Sex differences in recovery of quality of life 12 months post-fracture in community-dwelling older adults: analyses of the Australian arm of the International Costs and Utilities Related to Osteoporotic Fractures Study (AusICUROS)

In this study of 695 Australian older adults (aged ≥50 years), we found that men and women had a similar trajectory of health-related quality of life (HRQoL) recovery following fragility fracture at any skeletal site. These results provide us with critical knowledge that improves our understanding of health outcomes post-fracture.

INTRODUCTION

Mortality is higher in men than that in women following a fragility fracture, but it is unclear whether recovery of patient-reported outcomes such as health-related quality of life (HRQoL) differs between sexes. This study aimed to identify sex differences in HRQoL recovery 12 months post-fracture.

METHODS

Data were from the Australian arm of the International Costs and Utilities Related to Osteoporotic Fractures Study (AusICUROS). Participants recruited to AusICUROS were adults aged ≥50 years who sustained a fragility fracture. HRQoL was measured using the EQ-5D-3L at three time-points post-fracture: within 2 weeks (including pre-fracture recall) and at 4 and 12 months. Multivariate logistic regression analyses were undertaken, adjusting for confounders including age, education, income, and healthcare utilization post-fracture.

RESULTS

Overall, 695 AusICUROS participants (536 women, 77.1%) were eligible for analysis with fractures at the hip (n = 150), distal forearm (n = 261), vertebrae (n = 61), humerus (n = 52), and other skeletal sites (n = 171). At the time of fracture, men were younger, reported a higher income, and were more likely to be employed, compared with women. For all fracture sites combined, there were no differences between men and women in recovery to pre-fracture HRQoL at 12-month follow-up (adjusted OR = 1.09; 95% CI: 0.75-1.61). When stratified by fracture site, no significant sex differences were seen for hip (OR = 1.02; 95% CI: 0.42-2.52), distal forearm (OR = 1.60; 95% CI: 0.68-3.78), vertebral (OR = 2.28; 95% CI: 0.61-8.48), humeral (OR = 1.62; 95% CI: 0.16-9.99), and other fractures (OR = 1.00; 95% CI: 0.44-2.26).

CONCLUSION

Community-dwelling men and women who survived the 12 months following fragility fracture had a similar trajectory of HRQoL recovery at any skeletal site.

Development and validation of the risk engine for an Australian Health Economics Model of Osteoporosis

The Australian Health Economics Model of Osteoporosis (AusHEMO) has shown good face, internal and cross validities, and can be used to assist healthcare decision-making in Australia.

PURPOSE

This study aimed to document and validate the risk engine of the Australian Health Economics Model of Osteoporosis (AusHEMO).

METHODS

AusHEMO is a state-transition microsimulation model. The fracture risks were simulated using fracture incidence rates from the Dubbo Osteoporosis Epidemiology Study. The AusHEMO was validated regarding its face, internal and cross validities. Goodness-of-fit analysis was conducted and Lin's coefficient of agreement and mean absolute difference with 95% limits of agreement were reported.

RESULTS

The development of AusHEMO followed general and osteoporosis-specific health economics guidelines. AusHEMO showed good face validity regarding the model's structure, evidence, problem formulation and results. In addition, the model has been proven good internal and cross validities in goodness-of-fit test. Lin's coefficient was 0.99, 1 and 0.94 for validation against the fracture incidence rates, Australian life expectancies and residual lifetime fracture risks, respectively.

CONCLUSIONS

In summary, the development of the risk engine of AusHEMO followed the best practice for osteoporosis disease modelling and the model has been shown to have good face, internal and cross validities. The AusHEMO can be confidently used to predict long-term fracture-related outcomes and health economic evaluations when costs data are included. Health policy-makers in Australia can use the AusHEMO to select which osteoporosis interventions such as medications and public health interventions represent good value for money.

The interactions between MRI-detected osteophytes and bone marrow lesions or effusion-synovitis on knee symptom progression: an exploratory study

OBJECTIVES

To investigate the longitudinal association between MRI-detected osteophyte scores and progression of knee symptoms, and whether the association was modified in the presence of bone marrow lesions (BMLs) or effusion-synovitis.

METHODS

Data from Vitamin D Effects on Osteoarthritis (VIDEO) study, a randomized, double-blinded and placebo-controlled clinical trial in symptomatic knee osteoarthritis (OA) patients, were analyzed as an exploratory study. Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) was used to assess knee symptoms. Osteophytes, BMLs and effusion-synovitis were measured using MRI.

RESULTS

334 participants with MRI information and WOMAC score (baseline and follow-up) were included in the analyses, with 24.3% of them having knee pain increased 2 years later. Statistically significant interactions were found between MRI-detected osteophytes and BMLs or effusion-synovitis on increased knee symptoms. In participants with BMLs, higher baseline scores of MRI-detected osteophytes in most compartments were significantly associated with increased total knee pain, weight-bearing pain, stiffness, and physical dysfunction, after adjustment for age, sex, body mass index, intervention and effusion-synovitis. In participants with effusion-synovitis, higher baseline scores of MRI-detected osteophytes in almost all the compartments were significantly associated with increased total knee pain, weight-bearing pain, stiffness, and physical dysfunction, after adjustment for age, sex, body mass index, intervention and BMLs. In contrast, MRI-detected osteophyte scores were generally not associated with knee symptom progression in participants without baseline BMLs or effusion-synovitis.

CONCLUSIONS

MRI-detected OPs are associated with increased total knee pain, weight-bearing knee pain, stiffness and physical dysfunction in participants presenting BMLs or effusion-synovitis, but not in participants lacking BMLs or effusion-synovitis. This suggests they could interact with bone or synovial abnormalities to induce symptoms in knee OA.

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.

The cross-sectional and longitudinal associations of dietary patterns with knee symptoms and MRI detected structure in patients with knee osteoarthritis

OBJECTIVES

To examine the cross-sectional and longitudinal associations of dietary patterns with knee symptoms and structures in patients with knee osteoarthritis (OA).

METHODS

Participants with symptomatic knee OA were recruited from a randomised, placebo-controlled trial conducted in Tasmania (N = 259) and Victoria (N = 133). Diet was assessed by the Anti-Cancer Council of Victoria food frequency questionnaire. Factor analysis was used to identify dietary patterns. Knee symptoms were assessed using Western Ontario and McMaster Universities Arthritis Index (WOMAC) and structures using MRI. Multivariable linear regressions were used to examine associations.

RESULTS

Three dietary patterns ("high-fat", "healthy" and "mixed") were identified in whole sample. Participants with higher "healthy pattern" score had lower total WOMAC, pain, function and stiffness scores at baseline but the associations were not significant over 24 months. Three ("western", "vegetable and meat" and "mediterranean") and two ("processed" and "vegetable") patterns were identified in Tasmania and Victoria, respectively. Cross-sectionally, only "mediterranean pattern" and "vegetable pattern" scores were significantly and negatively associated with total WOMAC or function scores. Longitudinally, participants with higher "western pattern" had worsening function (β: 0.35, 95%CI: 0.03, 0.67) and total WOMAC (β: 0.40, 95%CI: 0.07, 0.72) scores; furthermore, "vegetable pattern" was associated with decreased WOMAC stiffness score (β: -0.47, 95%CI: -0.93, -0.02). In contrast, dietary patterns were largely not associated with structural changes.

CONCLUSION

Some healthy dietary patterns were associated with reduced joint symptoms but dietary patterns were not associated with joint structure in this sample with knee OA. Further studies are required to confirm these findings.

Incidence and circumstances of falls among middle-aged women: a cohort study

This was the first study assessing falls prospectively in middle-aged women. The 1-year incidence was 42% for any fall, which suggest falls are a major issue in middle-aged women. Middle-aged women, particularly those sustaining a fall, could be a target group for fall-prevention strategies.

PURPOSE

Incidence and circumstances of falls in middle-aged people are poorly understood. This cohort study aimed to elucidate the incidence and circumstances of falls over 1 year in middle-aged women.

METHODS

Falls were recorded monthly for 1 year by questionnaire in 2017-2019 in a population-based sample of women aged 41-62 years. The incidence of falls and injurious falls and related circumstances were descriptively analysed.

RESULTS

Of 273 women, 115 sustained 209 falls. The 1-year incidence was 42% for any fall, 17% for multiple (two or more) falls, and 24% for injurious falls. The incidence was greater in older age groups for any fall (33, 45, and 44% for people aged < 50, 50-55, and > 55 years, respectively), multiple falls (7, 14, and 22%) and injurious falls (15, 20, and 28%), although only the incidence of multiple falls was significantly increased across the three age groups (P = 0.01). Most falls occurred outdoors (71%) and were attributed to tripping and slipping (60%) CONCLUSIONS: Falls are a major issue in middle-aged women, a group that has been largely ignored in the prevention of falls. Middle-aged women, in particular those sustaining a fall, could be a target group for fall-prevention strategies. Future studies are needed to identify risk factors for falling in this population so as inform the development of strategies for preventing falls in middle-aged women.

Once-yearly zoledronic acid and change in abdominal aortic calcification over 3 years in postmenopausal women with osteoporosis: results from the HORIZON Pivotal Fracture Trial

This study evaluated whether zoledronic acid (ZA) inhibited the progression of abdominal aortic calcification (AAC) over 3 years in 502 postmenopausal women with osteoporosis. AAC progressed in a similar proportion of participants in the ZA (29%) and placebo (31%) groups, suggesting no effect of ZA on AAC progression.

INTRODUCTION

Bisphosphonate use is associated with reduced risk of all-cause mortality and cardiovascular events. The underlying mechanisms are uncertain but may include effects on vascular calcification. This study aimed to evaluate the effect of zoledronic acid (ZA) on abdominal aortic calcification (AAC) in postmenopausal women with osteoporosis.

METHODS

This was a post hoc analysis of the HORIZON Pivotal Fracture Trial that included 502 postmenopausal women (mean age 72.5 years) with osteoporosis (234 received ZA and 268 placebo). AAC scores (range, 0-8) were assessed from paired spine X-rays at baseline and after 3 years. Progression of AAC was defined as any increase in AAC score. The association between change in hip and femoral neck bone mineral density and change in AAC score was also assessed.

RESULTS

At baseline, 292 (58.2%) participants had AAC (i.e., AAC score > 0), with AAC scores similar in the two intervention groups (median [interquartile range], 1 [0 to 2] for both; p = 0.98). Over 3 years, AAC progressed in a similar proportion of participants in both groups (ZA 29% and placebo 31%; p = 0.64). Change in bone mineral density and change in AAC score were not correlated.

CONCLUSION

Once-yearly zoledronic acid did not affect progression of AAC over 3 years in postmenopausal women with osteoporosis.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00049829.

Comparison of radiographic and MRI osteoarthritis definitions and their combination for prediction of tibial cartilage loss, knee symptoms and total knee replacement: a longitudinal study

OBJECTIVE

To describe the value of radiographic- and magnetic resonance imaging (MRI)-defined tibiofemoral osteoarthritis (ROA and MRI-OA, respectively) and in combination for predicting tibial cartilage loss, knee pain and disability and total knee replacement (TKR) in a population-based cohort.

DESIGN

A radiograph and 1.5T MRI of the right knee was performed. ROA and MRI-OA at baseline were defined according to the Osteoarthritis Research Society International atlas and a published Delphi exercise, respectively. Tibial cartilage volume was measured over 2.6 and 10.7 years. Knee pain and disability were assessed at baseline, 2.6, 5.1 and 10.7 years. Right-sided TKRs were assessed over 13.5 years.

RESULTS

Of 574 participants (mean 62 years, 49% female), 8% had ROA alone, 15% had MRI-OA alone, 13% had both ROA and MRI-OA. Having ROA (vs. no ROA) and MRI-OA (vs. no MRI-OA) predicted greater tibial cartilage loss over 2.6 years (-75.9 and -86.4 mm³/year) and higher risk of TKR over 13.5 years (Risk Ratio [RR]: 15.0 and 10.9). Only MRI-OA predicted tibial cartilage loss over 10.7 years (-7.1 mm³/year) and only ROA predicted onset and progression of knee symptoms (RR: 1.32-1.88). In participants with both MRI-OA and ROA, tibial cartilage loss was the greatest (over 2.6 years: -116.1 mm³/year; over 10.7 years: -11.2 mm³/year), and the onset and progression of knee symptoms (RR: 1.75-2.89) and risk of TKR (RR: 50.9) were the highest.

CONCLUSIONS

The Delphi definition of MRI-OA is not superior to ROA for predicting structural or symptomatic OA progression but, combining MRI-OA and ROA has much stronger predictive validity.

FRI0383 A RANDOMISED PLACEBO-CONTROLLED CLINICAL TRIAL OF CURCUMA LONGA EXTRACT FOR TREATING SYMPTOMS AND EFFUSION-SYNOVITIS OF KNEE OSTEOARTHRITIS (CURKOA TRIAL)

Background:

Pharmacological therapies are limited, associated with off-target effects, are frequently contraindicated, and only modestly effective for pain in osteoarthritis (OA). Effusion and synovitis are common in OA and are associated with symptomatic and structural progression of OA.Curcuma longa(Turmeric) extract has anti-inflammatory effects and is gaining popularity in the treatment of OA despite the lack of high-quality evidence.

Objectives:

The CurKOA trial aimed to determine the efficacy ofCurcuma longaextract for reducing knee symptoms and effusion-synovitis in patients with symptomatic knee OA and knee effusion-synovitis.

Methods:

In this randomised, double-blind, placebo-controlled trial, participants with significant knee pain (≥ 40 mm on a 100-mm visual analog scale [VAS]), symptomatic knee OA (by ACR criteria) and ultrasound defined effusion-synovitis were randomised to receiveCurcuma longaextract (80% aqueous based extract standardized to turmerosaccharides + 20% curcuminoids, 2 × 500 mg capsules/day) or identical placebo for 12 weeks. Knee MRI scans were obtained at baseline and 12 weeks. Coprimary outcomes were changes in knee pain assessed by VAS and change in knee effusion-synovitis volume assessed by MRI over 12 weeks.

Results:

Among 70 participants (36 receivedCurcuma longa, 34 received placebo, age 61.8±8.6 years, 56% female),Curcuma longasignificantly improved VAS knee pain compared to placebo (-9.11mm, 95% confidence interval [CI] [- 17.79 to -0.44]) over 12 weeks, equivalent to a standardised effect size of 0.50. There was no significant between group difference in change in effusion-synovitis volume (3.24 mL [-0.33, 6.82]). There were significantly greater reductions in WOMAC knee pain (-47.22mm [-81.22, -13.22]), WOMAC function (-112.26mm [-222.79 to -1.74]) and significantly more OARSI-OMERACT treatment responders (63% treatment vs. 38% placebo [Risk Ratio=1.64 (1.00 to 2.70)]) in theCurcuma longagroup compared to the placebo group. There was no significant between-group difference in lateral femoral cartilage T2 relaxation time (-0.38 ms [- 1.10 to 0.34]) assessed from compositional MRI. The incidence of adverse events was similar in theCurcuma longa(n=14 (39%)) and placebo (n=18 (53%)) groups over 12 weeks (P=0.24).

Conclusion:

An extract ofCurcuma longasignificantly improved knee pain in an inflammatory phenotype of knee OA patients over 12 weeks compared to placebo but had no effect on knee effusion-synovitis and cartilage composition assessed using MRI. The moderate effect size of the treatment supports the use ofCurcuma longaextract for the symptomatic management of knee OA.

Figure 1.

Disclosure of Interests:

None declared

SAT0447 CORRELATES OF RADIAL BONE MICROARCHITECTURES IN OLDER ADULTS

Background:

Weight, dietary patterns, vitamin D, physical activity and grip strength have been suggested to be associated with bone loss in older adults. However, studies have yet been performed to investigate the associations between these factors and radial bone microarchitecture.

Objectives:

This study aimed to describe the associations of weight, dietary patterns, serum 25-hydroxyvitamin D (25(OH)D) concentrations, physical activity and grip strength with bone measures in older adults.

Methods:

Cross-sectional data on 201 older adults (mean age 72 years, female 46%) from a population-based cohort study were analysed. Weight, dietary patterns, serum 25(OH)D concentrations, physical activity (steps per day), grip strength were collected and analysed from baseline to 10-year follow-up. Areal bone mineral density (aBMD) at spine, hip and whole body were measured by dual-energy X-ray absorptiometry (DXA). Radial cortical and trabecular bone microarchitectures were measured by high-resolution peripheral computed tomography (HRpQCT). Multivariable linear regression was used to analyse associations of study factors with bone measures.

Results:

Weight was positively associated with radial bone area (total: β=0.18, 95% CI: 0.07, 0.29; cortical: β=0.12, 95% CI: 0.03, 0.21; trabecular: β=0.18, 95% CI: 0.05, 0.32), and was inversely associated with compact cortical volumetric bone mineral density (vBMD) (β= -0.19, 95% CI: -0.37, -0.01) and trabecular thickness (β= -0.25, 95% CI: -0.43, -0.07). Ten-year changes in weight were not significantly associated with bone measures, apart from radial trabecular separation (β= 0.15, 95%CI: 0.009, 0.28). Western dietary pattern scores were inversely associated with radial vBMD (total: β= -0.17, 95% CI: -0.32, -0.01; cortical: β= -0.19, 95% CI: -0.34, -0.04; compact cortical: β= -0.19, 95% CI: -0.34, -0.04; outer transitional zone: β= -0.20, 95% CI: -0.35, -0.06), and were positively associated with cortical porosity (cortical: β= 0.18, 95% CI: 0.03, 0.33; compact cortical: β= 0.19, 95% CI: 0.04, 0.34; outer transitional zone: β= 0.20, 95% CI: 0.06, 0.35). Steps per day were not significantly associated with bone measures, apart from inner transitional zone area and thickness (β= 0.12, 95% CI: 0.003, 0.24; β= 0.19, 95% CI: 0.05, 0.33). Healthy food pattern scores, serum 25(OH)D and grip strength were not significantly associated with radial HRpQCT measures.

Conclusion:

Higher weight, but not weight change, was beneficial for radial cortical and trabecular bone area but also associated with worse compact cortical vBMD and trabecular thickness. Higher western dietary pattern scores had adverse effects on radial vBMD and cortical porosity while physical activity had inconsistent associations.

Disclosure of Interests:

None declared

A novel method for assessing proximal tibiofibular joint on MR images in patients with knee osteoarthritis

OBJECTIVES

To validate a method to measure the morphological parameters of the proximal tibiofibular joint (PTFJ) in patients with knee osteoarthritis (OA).

METHODS

408 participants were examined in this cross-sectional subject-based study. We calculated the fibular contacting area of PTFJ (S) and its projection areas onto the horizontal plane (load-bearing area, Sτ), the sagittal plane (lateral stress-bolstering area, Sφ) and the coronal plane (posterior stress-bolstering area, Sυ). Joint space narrowing (JSN) and osteophyte was measured using radiographs. Cartilage defects, bone marrow lesions (BMLs) and cartilage volume were evaluated using magnetic resonance imaging (MRI).

RESULTS

The average PTFJ fibular contacting area was 2.4 cm² (SD, ±0.7 cm²). Intra-observer and inter-observer reliabilities of measures of PTFJ morphological parameters were excellent (≥0.90). S, Sτ and Sφ were significantly associated with JSN in the medial tibiofemoral compartment (PR: 1.40, 95% CI 1.10-1.78; PR: 1.65, 95% CI 1.25-2.18 and PR: 0.53, 95% CI 0.29-0.97, respectively). There was a significantly positive association between S, Sτ and medial and/or femoral tibial cartilage defects. S, Sτ and Sυ were significantly and positively associated with medial and/or femoral tibial BMLs (PR: 1.36, 95% CI 1.12-1.64; PR: 1.47, 95% CI 1.17-1.83; and PR: 1.39, 95% CI 1.06-1.82, respectively) after adjustment. S and Sτ were significantly and negatively associated with medial tibial cartilage volume.

CONCLUSIONS

This novel method to assess the morphological parameters of PTFJ in MRI is reproducible. These parameters are associated with knee radiographic and MRI-based OA-related structural abnormalities, suggesting clinical construct validity. Its predictive validity needs to be examined in future longitudinal studies.

Knee effusion-synovitis volume measurement and effects of vitamin D supplementation in patients with knee osteoarthritis

OBJECTIVE

To develop a measure of knee joint effusion-synovitis volume and to examine the effect of vitamin D supplementation on effusion-synovitis in people with knee osteoarthritis (OA) and low vitamin D levels over 24 months.

METHOD

Symptomatic knee OA patients with low 25-(OH)D levels (12.5-60 nmol/l) were recruited for a multi-centre, randomised, placebo-controlled and double-blind trial. Participants (age 63 ± 7 years, 208 females) were allocated to either 50,000 IU monthly vitamin D₃ (n = 209) or placebo (n = 204) for 24 months. Knee effusion-synovitis volume in suprapatellar and other regions was measured on magnetic resonance imaging (MRI) using OsiriX software. The intra-class correlation coefficients (ICCs) were used to test inter- and intra-rater reliabilities. The least significant change criterion was used to define the increase/decrease in effusion-synovitis volume.

RESULT

The reproducibilities of effusion-synovitis volume measurement were high with ICCs ranging from 0.93 to 0.99. Over 24 months, effusion-synovitis volume remained stable in the vitamin D group but increased in placebos with a significant between-group difference (-1.94 ml, 95% confidence interval (CI): -3.54, -0.33). This effect was evident in those with baseline effusion-synovitis and with suprapatellar effusion-synovitis. The proportion with an increase in effusion-synovitis volume was lower in the vitamin D group than placebo (risk ratio (RR): 0.87, 95% CI: 0.77, 0.97).

CONCLUSION

This highly reproducible effusion-synovitis volume measurement could be a promising outcome measure in OA trials. Vitamin D supplementation could retard the progression of effusion-synovitis which can potentially benefit people with an inflammatory OA phenotype.

Associations between endogenous sex hormones and MRI structural changes in patients with symptomatic knee osteoarthritis

OBJECTIVE

To investigate the longitudinal association between endogenous sex hormones and knee osteoarthritis (OA) structures and pain.

METHOD

We examined 200 participants (mean age 63.0 ± 7.3 years) from a clinical trial of vitamin D supplement for symptomatic knee OA. Serum levels of estradiol, progesterone, testosterone and sex hormone binding globulin (SHBG) were analyzed at baseline and 24 months later. Magnetic resonance imaging (MRI) scans of selected knee were obtained at both baseline and follow-up for the measurement of cartilage volume, cartilage defects, bone marrow lesions (BMLs) and effusion-synovitis volume. Knee pain was assessed using a 100 mm visual analogue scale (VAS). Longitudinal data were analyzed using linear mixed-effects model.

RESULTS

One hundred and seven males and 93 females were included in this study. For females, after adjustment for age, body mass index (BMI), and vitamin D level, progesterone was positively associated with cartilage volume (β = 0.12 mm³ per quartile, P < 0.01). Estradiol levels were associated with lower grades of BMLs (β = -0.46 per quartile, P = 0.03), while estradiol (β = -1.28 per quartile, P = 0.04), progesterone (β = -1.56 per quartile, P < 0.01) and testosterone (β = -1.51 per quartile, P = 0.01) were inversely associated with effusion-synovitis volume. Testosterone was inversely associated with knee pain. No consistent associations were observed for males.

CONCLUSION

In women but not men, low serum levels of endogenous estradiol, progesterone and testosterone are associated with increased knee effusion-synovitis and possibly other OA-related structural changes. This may contribute to observed sex differences in knee OA.

Effectiveness of interventions to promote physical activity and/or decrease sedentary behaviour among rural adults: a systematic review and meta-analysis

Physical inactivity and overweight and obesity are more prevalent among rural than urban populations. This study aimed to review published evidence of the effectiveness of interventions to increase physical activity (PA) and/or decrease sedentary behaviour (SB) among rural adults and to identify factors associated with effectiveness. Seven electronic databases were searched for controlled trials of a PA or SB intervention. Meta-analysis was conducted using random effects models and meta-regression. Thirteen studies were included in the qualitative synthesis (n = 4,848 participants) and 12 in the meta-analysis (n = 4,820). All studies were interventions to increase PA. Overall, there was no effect on PA (standardized mean difference [SMD] 0.11; 95% confidence interval [CI] -0.04, 0.25) or SB (SMD 0.07; 95% CI -0.33, 0.20). In PA subgroup analyses, studies employing objective outcome measures demonstrated effects in favour of the intervention (SMD 0.65, 95% CI 0.30, 1.00), while those using self-reported measures did not (SMD 0.00; 95% CI -0.11, 0.10). This review highlights significant gaps in our understanding of how best to promote PA and reduce SB among rural adults. Future studies should use objective measures of PA as study outcomes. The absence of interventions to decrease SB is of concern, with immediate action required to address this large knowledge gap.

Cross-sectional and longitudinal associations between serum inflammatory cytokines and knee bone marrow lesions in patients with knee osteoarthritis

OBJECTIVE

To describe cross-sectional and longitudinal associations between serum levels of interleukin (IL) - 6, IL-17A, IL-17F, IL-23 and knee bone marrow lesions (BMLs) in patients with knee osteoarthritis (OA).

DESIGN

Patients (n = 192) with symptomatic knee OA (mean 63 years, range 50-79, female 53%) were assessed at baseline and after 24 months. At each time point, serum IL-6, IL-17A, IL-17F and IL-23 were measured using Bio-Plex^® Multiplex Immunoassays with Luminex xMAP technology. Knee BMLs were scored using the modified whole organ MRI score (WORMS) from T2 weighted fat-suppressed fast spin echo magnetic resonance imaging (MRI). Multivariable linear regression and log binominal regression were used to determine the associations between cytokines and BMLs.

RESULTS

Baseline IL-6 (quarters) were significantly associated with total knee BMLs (P < 0.01 for the trend) as well as associated with an increase in BML score (P = 0.05 for the trend), after adjustment for confounders. Baseline IL-17F and IL-23 (highest quarters vs others) was associated with an increase in BML score in females (P = 0.04 for IL-17F; P = 0.01 for IL-23), but not in males, in multivariable analyses. In contrast, IL-17A was not significantly associated with BMLs in either females or males.

CONCLUSION

IL-6 is associated with increased knee BMLs in both females and males with OA. Serum IL-17F and IL-23 predicted increased knee BML scores in females only, suggesting that inflammation is involved in BML pathogenesis in knee OA, especially in women.

TRAIL REGISTRATION

ClinicalTrials.gov identifier: NCT01176344; Australian New Zealand Clinical Trials Registry: ACTRN12610000495022.

The interaction between weight and family history of total knee replacement with knee cartilage: a 10-year prospective study

OBJECTIVE

Although being overweight or obese is an important risk factor for the development of knee osteoarthritis (OA), the interplay between weight and genetic factors remains unclear. This study aimed to examine the associations between weight and knee cartilage volume/defects over 10 years in offspring having at least one parent with a total knee replacement (TKR) for primary knee OA and in controls without a knee OA family history.

METHOD

367 participants (183 offspring and 184 controls) aged from 26 to 61 years were recruited at baseline, and followed at 2 and 10 years later. T1-weighted magnetic resonance imaging (MRI) of the right knee was used to measure cartilage volume/defects at each time-point. Mixed-effects models were used with adjustment for potential confounders.

RESULTS

Study participants were middle-age adults (mean age 45 years, mean weight 77.5 kg at baseline). In multivariable analysis, increasing body weight was deleteriously associated with medial tibiofemoral cartilage volume (β = -0.28 ml, per 1 SD increase, 95% CI -0.49 to -0.07) and presence of medial tibiofemoral cartilage defects (RR = 1.27, per 1 SD increase, 95% CI 1.07 to 1.51) in offspring over 10 years. Similar associations were observed for lateral tibiofemoral cartilage volume (β = -0.19 ml, P = 0.059), and defects (RR = 1.24, P = 0.049). However, there were no statistically significant associations between weight and cartilage volume or defects in controls.

CONCLUSION

The adverse effects of increasing weight are stronger in the offspring of people with knee replacement for knee OA suggesting genetics-environment interaction with regard to overweight/obesity in the pathogenesis of knee OA particularly in the early stages.

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.

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.

Higher body mass index is associated with plantar fasciopathy/'plantar fasciitis': systematic review and meta-analysis of various clinical and imaging risk factors

QUESTION

What (risk) factors are associated with plantar fasciopathy (PF)?

DESIGN

Systematic review with meta-analyses.

PARTICIPANTS

Patients with PF.

FACTORS

All factors described in prospective, case-control or cross-sectional observational studies.

RESULTS

51 included studies (1 prospective, 46 case-control and 4 cross-sectional studies) evaluated a total of 104 variables. Pooling was possible for 12 variables. Higher body mass index (BMI) (BMI>27, OR 3.7 (95% CI 2.93 to 5.62)) in patients with PF was the only significant clinical association, and its effect was the strongest in the non-athletic subgroup. In people with PF compared to controls, pooled imaging data demonstrated a significantly thicker, hypoechogenic plantar fascia with increased vascular signal and perifascial fluid collection. In addition, people with PF were more likely to have a thicker loaded and unloaded heel fat pat, and bone findings, including a subcalcaneal spur and increased Tc-99 uptake. No significant difference was found in the extension of the first metatarsophalangeal joint.

CONCLUSIONS

We found a consistent clinical association between higher BMI and plantar fasciopathy. This association may differ between athletic and non-athletic subgroups. While consistent evidence supports a range of bone and soft tissue abnormalities, there is lack of evidence for the dogma of clinical and mechanical measures of foot and ankle function. Clinicians can use this information in shared decision-making.

Changes in quality of life associated with fragility fractures: Australian arm of the International Cost and Utility Related to Osteoporotic Fractures Study (AusICUROS)

We investigated change in health-related quality of life due to fracture in Australian adults aged over 50 years. Fractures reduce quality of life with the loss sustained at least over 12 months. At a population level, the loss was equivalent to 65 days in full health per fracture.

PURPOSE

We aimed to quantify the change in health-related quality of life (HRQoL) that occurred as a consequence of a fracture using the EQ-5D-3 L questionnaire.

METHODS

Adults aged ≥50 years with a low to moderate energy fracture were recruited from eight study centres across Australia. This prospective study included an 18-month follow-up of participants recruited within 2 weeks of a fracture (hip, wrist, humerus, vertebral and ankle). Information collected at baseline and 4, 12 and 18 months included characteristics of participants such as income level, education and prior fracture status. At 12 months post-fracture, the cumulative loss of quality of life was estimated using multivariate regression analysis to identify the predictors of HRQoL loss.

RESULTS

Mean HRQoL for all participants before fracture was 0.86, with wrist fracture having the highest pre-fracture HRQoL (0.90), while vertebral fracture had the lowest (0.80). HRQoL declined to 0.42 in the immediate post-fracture period. Only participants with a wrist, humerus or ankle fracture returned to their pre-fracture HRQoL after 18 months. An increased loss of HRQoL over 12 months was associated with HRQoL prior to the fracture, hospitalisation, education and fracture site. The multiple regression explained 30 % of the variation in the cumulative HRQoL loss at 12 months post-fracture for all fractures.

CONCLUSION

Low to moderate energy fractures reduce HRQoL, and this loss is sustained for at least 12 months or, in the case of hip and spine fractures, at least 18 months. At a population level, this represents an average loss of 65 days in full health per fragility fracture. This significant burden reinforces the need for cost-effective fracture prevention strategies.

Familial effects on structural changes relevant to knee osteoarthritis: a prospective cohort study

OBJECTIVE

Genetic factors play an important role in the pathogenesis of knee osteoarthritis (OA), but which knee structural changes mediate this is unclear. This study aimed to describe the differences in knee structural changes over 8-10 years between offspring having at least one parent with total knee replacement (TKR) for severe primary knee OA and controls with no family history of knee OA.

DESIGN

115 offspring (mean age 45 years) with a family history of TKR for severe knee OA were compared with 104 (mean age 46 years) controls. T1 or T2-weighted fat saturated magnetic resonance imaging (MRI) was performed respectively to evaluate knee cartilage defects, bone marrow lesions (BMLs), meniscal extrusion and tears at baseline and 10 years. Multivariate logistic regression model was used to adjust for potential confounders.

RESULTS

Offspring had a greater increase in cartilage defect score (1.03 vs 0.52, P = 0.007) and meniscal extrusion score (0.28 vs 0.10, P = 0.027) over 10 years, and a greater increase in meniscal tear score (0.40 vs 0.10, P = 0.012) over 8 years in the medial but not the lateral tibiofemoral compartment. Changes in BMLs over 8-years were not different between the two groups. These associations were independent of potential confounders, and strengthened after further adjustment for each other.

CONCLUSION

With the exception of BMLs, offspring with a family history of knee OA have a greater risk of increases in multiple knee structural abnormalities in the medial tibiofemoral compartment suggesting pleiotropic familial effects.

Meta-analyses to investigate gene-environment interactions in neuroepidemiology

BACKGROUND

Most chronic neurological diseases are caused by a combination of multiple genetic and environmental factors. Increasingly, gene-environment interactions (GxE) are being examined, providing opportunities to combine studies systematically using meta-analysis.

METHODS

Systematic review of the literature on how to examine GxE using observational study designs, and how to conduct a meta-analysis of studies on GxE.

RESULTS

Most methods and challenges related to a standard meta-analysis apply to a GxE meta-analysis. There are, however, some substantive differences. With GxE, there is the capability of using a case-only design. Research on GxE interactions may be more prone to publication bias, since interactions are usually not the primary hypothesis and only 'exciting' significant GxE findings are reported out of a range of secondary analyses. In disease aetiology research, there has been debate whether to measure interaction on a multiplicative or additive scale. There are some significant challenges associated with measuring interaction on an additive scale, and thus the uptake of the measures of additive interaction has been limited. As a result, the methods of analysing interaction have been less consistent and reporting has been highly variable. We suggest using the STROBE/STREGA reporting guidelines to allow evaluation of interaction on both scales.

CONCLUSIONS

We identified a number of differences of a GxE meta-analysis over a standard meta-analysis. Awareness of these issues is important. Using established reporting guidelines for GxE studies is recommended. The development of consortia for neurological disorders that include both genetic and environmental data might offer benefits for GxE meta-analyses in the future.

Vitamin D deficiency in Tasmania: a whole of life perspective

AIM

This study aims to describe the lifetime picture of vitamin D deficiency, as measured by serum 25(OH)D concentration, in Tasmania (latitude 43°S).

METHODS

Five cross-sectional studies were used: a sample of primary schoolchildren (n = 201, aged 7-8 years), two samples of adolescents (sample 1: n = 374, aged 15-18 years; sample 2: n = 136, aged 16-19 years), a sample of young to middle-aged adults (n = 262, aged 19-59 years) and a sample of older adults (n = 1092, aged 50-80 years).

RESULTS

In winter/spring, approximately two-thirds of the adolescents and adults (young, middle-aged and older) had 25(OH)D levels ≤50 nmol/L, and around 10% had 25(OH)D levels ≤25 nmol/L. The prevalence of vitamin D deficiency was much lower for primary schoolchildren (11.5% < 50 nmol/L, 0.5% ≤ 25 nmol/L). In summer/autumn, approximately one-third of the adolescents and adults had 25(OH)D levels ≤50 nmol/L, and very few had 25(OH)D levels ≤25 nmol/L. For the adolescents and adults, even among those who reported the highest category of sun exposure, approximately 45% had 25(OH)D levels ≤50 nmol/L in winter/spring.

CONCLUSIONS

Vitamin D deficiency was uncommon among our sample of primary school children but increased substantially during the teenage years and seemed to remain high throughout the rest of life, suggesting that mild vitamin D deficiency is endemic in Tasmania apart from in the very young.

Effectiveness of interventions to promote physical activity among socioeconomically disadvantaged women: a systematic review and meta-analysis

Physical activity is important for preventing weight gain and obesity, but women experiencing socioeconomic disadvantage are at high risk of inactivity. This study aimed to determine the effectiveness of interventions to increase physical activity among women experiencing disadvantage, and the intervention factors (i.e. physical activity measure, delivery mode, delivery channel, setting, duration, use of theory, behavioural techniques, participant age, risk of bias) associated with effectiveness. We conducted a meta-analysis of controlled trials using random-effects models and meta-regression. Seven databases were searched for trials among healthy women (18-64 years), which included a physical activity intervention, any control group, and statistical analyses of a physical activity outcome at baseline and post-intervention. Nineteen studies were included (n = 6,339). Because of substantial statistical heterogeneity (χ(2) = 53.61, df = 18, P < 0.0001, I(2) = 66%), an overall pooled effect is not reported. In subgroup analyses, between-group differences were evident for delivery mode, which modestly reduced heterogeneity (to 54%). Studies with a group delivery component had a standardized mean difference of 0.38 greater than either individual or community-based delivery. Programs with a group delivery mode significantly increase physical activity among women experiencing disadvantage, and group delivery should be considered an essential element of physical activity promotion programs targeting this population group.

Vitamin D and bone health in childhood and adolescence

Vitamin D plays a key role in bone metabolism. The link between vitamin D deficiency and rickets is well understood. However, subclinical vitamin D deficiency may also be detrimental to bone health in childhood. Its effects on bone mineralization have the potential to result in lower peak bone mass being attained, which could in turn contribute to increased fracture risk in both childhood and older adult life. As vitamin D deficiency is common globally, any detrimental effects of vitamin D deficiency on bone health are likely to have substantial public health implications. This review describes the current literature relevant to vitamin D and bone health in childhood and adolescence, with a particular emphasis on evaluating the emerging evidence for the impact of subclinical vitamin D deficiency on bone health and the effectiveness of vitamin D supplementation. The evidence suggests that subclinical vitamin D deficiency does affect bone acquisition, potentially beginning in utero and extending into adolescence. However, the effectiveness of vitamin D supplementation for improving bone health in situations of subclinical deficiency remains unclear, particularly in early life where there are few trials with bone density outcomes. The available evidence suggests that benefits are likely to be greatest in or even restricted to children with serum 25-hydroxyvitamin D levels at least below 50 nmol/L and possibly even lower than this. Trials of sufficient duration in deficient pregnant mothers, infants, and children are urgently required to address critical evidence gaps.

How do women change osteoporosis-preventive behaviours in their children?

OBJECTIVE

We have reported that a lifestyle intervention with mothers improved calcium intake and physical activity in both mothers and their children. In this study, we aimed to describe the strategies and approaches used by these mothers to improve their children's calcium intake and physical activity.

DESIGN

A qualitative study using semistructured interviews.

SETTING

Population-based convenience sample.

SUBJECTS

A subsample of 39 mothers were taken from a population-based random sample of 354 mothers who had participated in the original osteoporosis-prevention trial.

RESULTS

Mothers described specific dietary changes they made to increase their children's calcium intake. They also described strategies for improving calcium intake and physical activity such as raising awareness of the importance of calcium; ensuring calcium-rich foods were accessible; assessing their children's likes and dislikes and working within these; role modelling; information provision; taking a balanced approach to attempting behaviour change; and encouraging activities that they could do with their children. Mothers emphasized the general importance of a balanced diet and lifestyle, rather than just focussing on lifestyle factors specific to osteoporosis prevention.

CONCLUSION

Even without specific guidance, mothers are adept at developing strategies to apply to changing lifestyle behaviours in their children and identifying barriers to change. These results provide information, which could be incorporated into future interventions for lifestyle change in children and also provide further support for considering parent-focused approaches to this problem.