Association between popliteal artery wall thickness and structural progression in patients with symptomatic knee osteoarthritis.

OBJECTIVE: There is increasing evidence for the involvement of vascular disease in the pathogenesis of knee OA. Popliteal artery wall thickness can be used as a surrogate marker of atherosclerosis. We examined the association between popliteal artery wall thickness and knee cartilage volume in individuals with symptomatic knee OA. METHODS: This prospective cohort study analysed 176 participants from a randomized placebo-controlled trial examining the effect of atorvastatin on structural progression in knee OA. The participants underwent MRI of the study knee at baseline and 2-year follow-up. Popliteal artery wall thickness and tibial cartilage volume were measured from MRI using validated methods. The top quartile of the rate of tibial cartilage volume loss was defined as rapid progression. RESULTS: At baseline, every 10% increase in popliteal artery wall thickness was associated with 120.8 mm3 (95% CI 5.4, 236.2, P = 0.04) lower of medial tibial cartilage volume and 151.9 mm3 (95% CI 12.1, 291.7, P = 0.03) lower of lateral tibial cartilage volume. Longitudinally, for every 10% increase in popliteal artery wall thickness, the annual rate of medial tibial cartilage volume loss was increased by 1.14% (95% CI 0.09%, 2.20%, P = 0.03), and there was a 2.28-fold (95% CI 1.07, 4.83, P = 0.03) risk of rapid progression of medial tibial cartilage loss, adjusted for age, sex, BMI, tibial bone area, smoking, vigorous physical activity, and intervention group allocation. CONCLUSION: The findings support a role for vascular pathology in the progression of knee OA. Targeting atherosclerosis has the potential to improve outcomes in knee OA.

Association between arthritis and cardiovascular risk factors in community-based adults: an opportunity to target cardiovascular risk.

BACKGROUND: Undertreated risk factors are major contributors to the burden of cardiovascular disease (CVD). Those with arthritis have an increased prevalence of CVD risk factors. CVD risk factors are often asymptomatic, which may be a barrier their treatment. Arthritis causes pain and immobility, and is a common reason for individuals to seek healthcare. Our aims were to (1) examine the relationship between arthritis and CVD risk factors in Australian adults, and (2) calculate the proportion of CVD risk factors that could be reduced if individuals with arthritis were targeted. METHODS: This cross-sectional study uses data from the 2017-18 Australian National Health Survey which included 13,776 participants, categorised into young (18-39 years), middle aged (40-64 years) and older (≥ 65 years) adults. Hypertension, height and weight were measured. Arthritis, dyslipidemia and diabetes were self-reported. The associations between arthritis and CVD risk factors were examined using logistic regression, and the population attributable fraction (PAF) of arthritis for each CVD risk factor was calculated. RESULTS: Arthritis was reported by 4.0% of young adults, 28.8% of middle-aged adults and 54.5% of older adults. Those with arthritis were at increased odds of obesity (2.07 fold in young, 1.75 fold in middle-aged and 1.89 fold in older adults), increased odds of diabetes (5.70 fold in young, 1.64 fold in middle-aged and 1.37 fold in older adults), increased odds of hypertension (2.72 fold in young, 1.78 fold in middle-aged and 1.48 fold in older adults) and an increased odds of dyslipidaemia (4.64 fold in young, 2.14 fold in middle-aged and 1.22 fold in older adults) compared to those without arthritis. This elevated chance remained significant even after adjusting for obesity, with the exception of diabetes in the older population. This elevated chance remained significant even after adjusting for obesity, with the exception of diabetes in the older population. The PAF of the presence of arthritis for having at least one CVD risk factor was 30.7% in middle-aged adults and 70.4% in older adults. CONCLUSION: Australian adults of all ages with arthritis are at increased odds of having CVD risk factors. For young and middle-aged adults, this increased odds remains significant even when adjusted for obesity. Presentation to healthcare practitioners with arthritis is an opportunity to screen for asymptomatic CVD risk factors with the potential of improving outcomes for both diseases. By adopting an approach of managing arthritis and CVD risk factors in parallel, rather than in silos, we could reduce the burden of CVD risk factors by 20-30%.

Does aerobic exercise effect pain sensitisation in individuals with musculoskeletal pain? A systematic review.

BACKGROUND: Pain sensitisation plays a major role in musculoskeletal pain. However, effective treatments are limited, and although there is growing evidence that exercise may improve pain sensitisation, the amount and type of exercise remains unclear. This systematic review examines the evidence for an effect of aerobic exercise on pain sensitisation in musculoskeletal conditions. METHODS: Systematic searches of six electronic databases were conducted. Studies were included if they examined the relationship between aerobic physical activity and pain sensitisation in individuals with chronic musculoskeletal pain, but excluding specific patient subgroups such as fibromyalgia. Risk of bias was assessed using Cochrane methods and a qualitative analysis was conducted. RESULTS: Eleven studies (seven repeated measures studies and four clinical trials) of 590 participants were included. Eight studies had low to moderate risk of bias. All 11 studies found that aerobic exercise increased pressure pain thresholds or decreased pain ratings in those with musculoskeletal pain [median (minimum, maximum) improvement in pain sensitisation: 10.6% (2.2%, 24.1%)]. In these studies, the aerobic exercise involved walking or cycling, performed at a submaximal intensity but with incremental increases, for a 4-60 min duration. Improvement in pain sensitisation occurred after one session in the observational studies and after 2-12 weeks in the clinical trials. CONCLUSIONS: These findings provide evidence that aerobic exercise reduces pain sensitisation in individuals with musculoskeletal pain. Further work is needed to determine whether this translates to improved patient outcomes, including reduced disability and greater quality of life.

Efficacy of corticosteroids for hand osteoarthritis - a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: There is some evidence that corticosteroids may have a beneficial effect in hand osteoarthritis. We examined the efficacy of corticosteroids on symptoms and structural outcomes in hand osteoarthritis. METHODS: Ovid MEDLINE, Embase and Cochrane Central Register of Controlled Trials were searched from inception to October 2021 for randomized controlled trials investigating the efficacy of corticosteroids in hand osteoarthritis. Two authors independently screened records, extracted data, and assessed risk of bias using the RoB 2 tool. Standardized mean difference (SMD) or mean difference (MD) was calculated, and random-effects meta-analyses were performed. RESULTS: Of 13 included trials, 3 examined oral corticosteroids and clinical outcomes in any hand joints, 9 examined intra-articular injection of corticosteroids and clinical outcomes at the first carpometacarpal joint and one in the interphalangeal joints. In meta-analysis, oral corticosteroids reduced pain (SMD -0.53, 95% CI -0.79 to -0.28) and improved stiffness (MD -5.03, 95% CI -9.91 to -0.15; Australian Canadian Osteoarthritis Hand Index stiffness subscale) and function (SMD -0.37, 95% CI -0.63 to -0.12) at 4-6 weeks. However, there was no significant persistent effect on pain and function at 3 months which was 6-8 weeks after study medication was stopped. There was no significant effect of intra-articular corticosteroids on pain or function at 4-6 weeks or over 3-12 months in first carpometacarpal osteoarthritis. Two trials evaluated joint structure at 4-6 weeks: one study showed oral corticosteroids reduced synovial thickening, neither showed an effect on synovitis. CONCLUSIONS: There was low-certainty evidence for a medium effect of oral corticosteroids on pain relief and stiffness improvement and small-to-medium effect on functional improvement at 4-6 weeks, with no significant effect for intra-articular corticosteroids. Corticosteroids had no significant effect on any outcomes over longer term (3-12 months) off treatment. No trials examined the effect of corticosteroids on disease progression. The role of corticosteroids in hand osteoarthritis is limited.

Topical corticosteroid for treatment of hand osteoarthritis: study protocol for a randomised controlled trial.

BACKGROUND: Hand osteoarthritis is a common and disabling chronic joint disease with a lack of effective therapies. Emerging evidence suggests the role of local inflammation in causing pain in hand osteoarthritis. Corticosteroids are potent anti-inflammatory drugs used in many rheumatic diseases. The aim of this randomised, double-blind, placebo-controlled trial is to determine whether topical corticosteroid reduces pain over 6 weeks in patients with hand osteoarthritis. METHODS: One hundred participants with hand osteoarthritis will be recruited from the community in Melbourne, Australia, and randomly allocated in a 1:1 ratio to receive either topical Diprosone OV or placebo ointment administered 3 times daily on the painful hand joints for 6 weeks. The primary outcome is pain reduction (assessed by 100 mm visual analogue scale) at 6 weeks. The secondary outcomes include changes in pain and function assessed using Functional Index for Hand Osteoarthritis, Australian Canadian Osteoarthritis Hand Index, Michigan Hand Outcomes Questionnaire, and tender and swollen joint count at 6 weeks. Adverse events will be recorded. The primary analysis will be by intention to treat, including all participants in their randomised groups. DISCUSSION: This study will provide high-quality evidence to determine whether topical corticosteroid reduces pain over 6 weeks in patients with hand osteoarthritis, with major clinical and public health importance by informing clinical practice guidelines for the management of hand osteoarthritis and reducing the burden of the disabling disease. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry (ANZCTR), ACTRN12620000599976 . Registered 22 May 2020.

Effect of low-dose amitriptyline on reducing pain in clinical knee osteoarthritis compared to benztropine: study protocol of a randomised, double blind, placebo-controlled trial.

BACKGROUND: Knee osteoarthritis is a major cause of pain and disability. Pain control is poor, with most patients remaining in moderate to severe pain. This may be because central causes of pain, a common contributor to knee pain, are not affected by current treatment strategies. Antidepressants, such as amitriptyline, have been used to treat chronic pain in other conditions. The aim of this randomised, double blind, controlled trial, is to determine whether low dose amitriptyline reduces pain in people with painful knee osteoarthritis over 3 months compared to benztropine, an active placebo. METHODS/DESIGN: One hundred and sixty people with painful radiographic knee osteoarthritis will be recruited via clinicians, local and social media advertising. Participants will be randomly allocated in a 1:1 ratio to receive either low dose amitriptyline (25 mg) or active placebo (benztropine mesylate, 1 mg) for 3 months. The primary outcome is change from baseline in knee pain (WOMAC pain subscale) at 12 weeks. Secondary outcomes include change in function (total WOMAC) and the proportion of individuals achieving a substantial response (≥ 50% reduction in pain intensity, measured by Visual Analog Scale, VAS, from no pain to worst pain imaginable, 0-100 mm) and moderate response (≥ 30% reduction in pain intensity, measured by VAS) at 12 weeks. Intention to treat analyses will be performed. Subgroup analyses will be done. DISCUSSION: This study will provide high level evidence regarding the effectiveness of low dose amitriptyline compared to benztropine in reducing pain and improving function in knee OA. This trial has the potential to provide an effective new therapeutic approach for pain management in knee osteoarthritis, with the potential of ready translation into clinical practice, as it is repurposing an old drug, which is familiar to clinicians and with a well described safety record. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry prior to recruitment commencing ( ACTRN12615000301561 , March 31, 2015, amended 14 December 2018, February 2021). Additional amendment requested 18 July 2021.

Association between circulating 25-hydroxyvitamin D concentrations and hip replacement for osteoarthritis: a prospective cohort study.

BACKGROUND: To examine the association between circulating 25(OH)D concentrations and incidence of total hip replacement for osteoarthritis in a prospective cohort study. METHODS: This study examined a random sample of 2651 participants in the Melbourne Collaborative Cohort Study who had 25(OH)D concentrations measured from dried blood spots collected in 1990-1994. Participants who underwent total hip replacement for osteoarthritis between January 2001 and December 2018 were identified by linking the cohort records to the Australian Orthopaedic Association National Joint Replacement Registry. Cox proportional hazard regression was used to estimate hazard ratios (HR) and 95% confidence intervals (CI) of total hip replacement for osteoarthritis in relation to 25(OH)D concentrations, adjusted for confounders. RESULTS: Eighty-six men and eighty-seven women had a total hip replacement for osteoarthritis. Compared with men in the lowest (1st) quartile of 25(OH)D concentration, the HR for total hip replacement was 2.32 (95% CI 1.05, 5.13) for those in the 2nd quartile, 2.77 (95% CI 1.28, 6.00) for those in the 3rd quartile, and 1.73 (95% CI 0.75, 4.02) for those in the highest quartile of 25(OH)D concentrations (p for trend 0.02). There was little evidence of an association in women. CONCLUSIONS: Higher circulating 25(OH)D concentrations were associated with an increased risk of total hip replacement for osteoarthritis in men but not in women. Although the underlying mechanism warrants further investigation, our findings highlight the need to determine the optimal levels of circulating 25(OH)D to reduce the risk of hip osteoarthritis.

Association between clusters of back and joint pain with opioid use in middle-aged community-based women: a prospective cohort study.

BACKGROUND: To determine the relationship between clusters of back pain and joint pain and prescription opioid dispensing. METHODS: Of 11,221 middle-aged participants from the Australian Longitudinal Study of Women's Health, clusters of back pain and joint pain from 2001 to 2013 were identified using group-based trajectory modelling. Prescription opioid dispensing from 2003 to 2015 was identified by linking the cohort to Pharmaceutical Benefit Scheme dispensing data. Multinomial logistic regression was used to examine the association between back pain and joint pain clusters and dispensing of prescription opioids. The proportion of opioids dispensed in the population attributable to back and join pain was calculated. RESULTS: Over 12 years, 68.5 and 72.0% women reported frequent or persistent back pain and joint pain, respectively. There were three clusters ('none or infrequent', 'frequent' and 'persistent') for both back pain and joint pain. Those in the persistent back pain cluster had a 6.33 (95%CI 4.38-9.16) times increased risk of having > 50 opioid prescriptions and those in persistent joint pain cluster had a 6.19 (95%CI 4.18-9.16) times increased risk of having > 50 opioid prescriptions. Frequent and persistent back and joint pain clusters together explained 41.7% (95%CI 34.9-47.8%) of prescription opioid dispensing. Women in the frequent and persistent back pain and joint pain clusters were less educated and reported more depression and physical inactivity. CONCLUSION: Back pain and joint pain are major contributors to opioid prescription dispensing in community-based middle-aged women. Additional approaches to reduce opioid use, targeted at those with frequent and persistent back pain and joint pain, will be important in order to reduce the use of opioids and their consequent harm in this population.

The bulge sign - a simple physical examination for identifying progressive knee osteoarthritis: data from the Osteoarthritis Initiative.

OBJECTIVE: To examine whether the presence of bulge sign or patellar tap was associated with frequent knee pain, progression of radiographic OA (ROA) and total knee replacement (TKR). METHODS: This study included 4344 Osteoarthritis Initiative participants examined at baseline for bulge sign and/or patellar tap. The clinical signs were categorized as no (none at baseline and 2 years), resolved (present at baseline only), developed (present at 2 years only) and persistent (present at both time points). Frequent knee pain and progression of ROA over 4 years and TKR over 6 years were assessed. Binary logistic regression was used to examine the associations. RESULTS: A total of 12.7% of participants had bulge sign only, 2.0% had patellar tap only and 3.3% had both. A positive baseline bulge sign was associated with an increased risk of frequent knee pain [OR 1.31 (95% CI 1.04, 1.64), P = 0.02] and TKR [OR 1.47 (95% CI 1.06, 2.05), P = 0.02]. Developed bulge sign was associated with an increased risk of frequent knee pain [OR 1.75 (95% CI 1.34, 2.29), P < 0.001] and progressive ROA [OR 1.67 (95% CI 1.11, 2.51), P = 0.01]. Persistent bulge sign was associated with an increased risk of frequent knee pain [OR 1.60 (95% CI 1.09, 2.35), P = 0.02], progressive ROA [OR 1.84 (95% CI 1.01, 3.33), P = 0.045] and TKR [OR 2.13 (95% CI 1.23, 3.68), P = 0.007]. Patellar tap was not examined for its association with joint outcomes due to its low prevalence. CONCLUSION: The presence of bulge sign identifies individuals at increased risk of frequent knee pain, progression of ROA and TKR. This provides clinicians with a quick, simple, inexpensive method for identifying those at higher risk of progressive knee OA who should be targeted for therapy.

Association between increased signal intensity at the proximal patellar tendon and patellofemoral geometry in community-based asymptomatic middle-aged adults: a cross-sectional study.

BACKGROUND: Histological and epidemiological data suggest that increased signal intensity at the proximal patellar tendon on magnetic resonance imaging is a response to tendon loading. As patellofemoral geometry is a mediator of loading, we examined the association between patellofemoral geometry and the prevalence of increased signal intensity at the patellar tendon in community-based middle-aged adults. METHODS: Two hundred-one adults aged 25-60 years in a study of obesity and musculoskeletal health had the patellar tendon assessed from magnetic resonance imaging. Increased signal intensity at the proximal patellar tendon was defined as hyper-intense regions of characteristic pattern, size and distribution on both T1- and T2-weighted sequences. Indices of patellofemoral geometry, including Insall-Salvati ratio, patellofemoral congruence angle, sulcus angle, and lateral condyle-patella angle, were measured from magnetic resonance imaging using validated methods. Binary logistic regression was used to examine the association between patellofemoral geometrical indices and the prevalence of increased signal intensity at the patellar tendon. RESULTS: The prevalence of increased signal intensity at the patellar tendon was 37.3%. A greater Insall-Salvati ratio (odds ratio 0.80, 95% confidence interval 0.66-0.97 per 0.1 change in the ratio, p = 0.02), indicative of a higher-riding patella, and a larger patellofemoral congruence angle (odds ratio 0.91, 95% confidence interval 0.85-0.98 per 5 degree change in the angle, p = 0.01), indicating a more laterally placed patella, were associated with reduced odds of increased signal intensity at the patellar tendon. Sulcus angle and lateral condyle-patella angle were not significantly associated with the odds of increased signal intensity at the patellar tendon. CONCLUSIONS: In community-based asymptomatic middle-aged adults, increased signal intensity at the patellar tendon was common and associated with Insall-Salvati ratio and patellofemoral congruence angle, suggesting a biomechanical mechanism. Such work is likely to inform tissue engineering and cell regeneration approaches to improving outcomes in those with tendon pathology.

Association between hip muscle cross-sectional area and hip pain and function in individuals with mild-to-moderate hip osteoarthritis: a cross-sectional study.

BACKGROUND: To examine the associations between hip muscle cross-sectional area and hip pain and function in community-based individuals with mild-to-moderate hip osteoarthritis. METHODS: This study included 27 participants with mild-to-moderate hip osteoarthritis. Cross-sectional area of hip muscles, including psoas major, rectus femoris, gluteus maximus, gluteus medius and minimus, adductor longus and magnus, obturator internus, and obturator externus, were measured from magnetic resonance images. Hip pain and function were evaluated using the Hip Disability and Osteoarthritis Outcome Score (HOOS) categorised into 5 subscales: pain, symptoms, activity of daily living, sport and recreation function, and hip-related quality of life (for each subscale 0 representing extreme problems and 100 representing no problems). RESULTS: Mean age of the 27 participants was 63.2 (SD 7.6) years and 66.7% (n = 18) were female. After adjusting for age and gender, greater cross-sectional area of adductor longus and magnus was associated with a higher HOOS score in quality of life (regression coefficient 1.4, 95% confidence interval (CI) 0.2-2.7, p = 0.02), activity of daily living (regression coefficient 1.3, 95% CI 0.1-2.6, p = 0.04) and sport and recreation function (regression coefficient 1.6, 95% CI 0.1-3.0, p = 0.04). There was a trend towards an association between greater cross-sectional area of psoas major and a higher quality of life score (regression coefficient 3.6, 95% CI - 0.5 to 7.7, p = 0.08). The cross-sectional area of hip muscles was not significantly associated with HOOS pain or symptom score. CONCLUSION: Greater cross-sectional area of hip adductors was associated with better function and quality of life in individuals with mild-to-moderate hip osteoarthritis. Greater cross-sectional area of hip flexors might be associated with better quality of life. These findings, while need to be confirmed in longitudinal studies, suggest that targeting the hip adductor and flexor muscles may improve function and quality of life in those with mild-to-moderate hip osteoarthritis.

Knee effusion volume assessed by magnetic resonance imaging and progression of knee osteoarthritis: data from the Osteoarthritis Initiative.

Objective: To examine whether baseline knee joint effusion volume and the change in effusion volume over 1 year are associated with cartilage volume loss, progression of radiographic OA (ROA) over 4 years and risk of total knee replacement over 6 years. Methods: This study included 4115 Osteoarthritis Initiative participants with knee joint effusion volume quantified by MRI at baseline. The change in effusion volume over 1 year was assessed. Cartilage volume loss and progression of ROA over 4 years were assessed using MRI and X-ray and total knee replacement over 6 years was assessed. Multiple linear regression and binary logistic regression were used for data analyses. Results: Baseline knee effusion volume (per 5 ml) was positively associated with a loss of medial and lateral cartilage volume [regression coefficient 0.13%/year (95% CI 0.10, 0.17) and 0.13%/year (95% CI 0.10, 0.16), respectively, both P < 0.001], progression of ROA [odds ratio (OR) 1.28 (95% CI 1.20, 1.37), P < 0.001], and risk of knee replacement [OR 1.12 (95% CI 1.05, 1.20), P = 0.001]. A 5 ml increase in knee effusion volume over 1 year was positively associated with medial cartilage volume loss [regression coefficient 0.09%/year (95% CI 0.04, 0.15), P = 0.001], progression of ROA [OR 1.21 (95% CI 1.11, 1.33), P < 0.001] and risk of knee replacement [OR 1.24 (95% CI 1.12, 1.37), P < 0.001]. Conclusions: Knee joint effusion volume assessed from MRI provides a continuous and sensitive measure that was associated with cartilage volume loss, progression of ROA and risk of total knee replacement. It may provide a method to identify individuals with an inflammatory OA phenotype who are at higher risk of disease progression.

Impact of fetal growth and preterm birth on the retinal microvasculature in mid-adulthood.

OBJECTIVE: We hypothesized that preterm birth and being born SGA would be associated with changes in retinal microvascular architecture and that these changes would be more marked among those born preterm. We further hypothesized that these microvascular changes would correlate with early markers of CVD in mid-adulthood. METHODS: The Cardiovascular Risk in Young Finns Study included randomly selected children from 5 Finnish University cities. Retinal microvascular architecture of participants born preterm, born at term and SGA and a control group born at term and AGA were compared (aged 34-49 years). RESULTS: In participants born preterm, arteriolar tortuosity (×10(2)) was higher-means (standard error), 0.06 (0.01) versus 0.04 (0.01), p = 0.001, arteriolar length (pixels) were greater-644.9 (35.9) versus 591.7 (33.5), p = 0.007 and arteriolar diameters (pixels) were narrower-19.9 (0.4) versus 20.3 (0.3), p = 0.034 compared to participants born AGA, after adjustment. In participants born SGA, only arteriolar tortuosity was higher-0.05 (0.01) versus 0.04 (0.01), p = 0.074 compared to participants born AGA. CONCLUSION: This study demonstrated that being born SGA and in particular preterm birth are associated with changes in retinal microvascular architecture. The prenatal and immediate postnatal environment may contribute to the mechanisms.

Could low grade bacterial infection contribute to low back pain? A systematic review.

BACKGROUND: Recently, there has been both immense interest and controversy regarding a randomised, controlled trial which showed antibiotics to be effective in the treatment of chronic low back pain (disc herniation with Modic Type 1 change). While this research has the potential to result in a paradigm shift in the treatment of low back pain, several questions remain unanswered. This systematic review aims to address these questions by examining the role of bacteria in low back pain and the relationship between bacteria and Modic change. METHODS: We conducted electronic searches of MEDLINE and EMBASE and included studies that examined the relationship between bacteria and back pain or Modic change. Studies were rated based on their methodological quality, a best-evidence synthesis was used to summarise the results, and Bradford Hill's criteria were used to assess the evidence for causation. RESULTS: Eleven studies were identified. The median (range) age and percentage of female participants was 44.7 (41-46.4) years and 41.5% (27-59%), respectively, and in 7 of the 11 studies participants were diagnosed with disc herniation. Nine studies examined the presence of bacteria in spinal disc material and all identified bacteria, with the pooled estimate of the proportion with positive samples being 34%. Propionibacterium acnes was the most prevalent bacteria, being present in 7 of the 9 studies, with median (minimum, maximum) 45.0% (0-86.0) of samples positive. The best evidence synthesis found moderate evidence for a relationship between the presence of bacteria and both low back pain with disc herniation and Modic Type 1 change with disc herniation. There was modest evidence for a cause-effect relationship. CONCLUSIONS: We found that bacteria were common in the spinal disc material of people undergoing spinal surgery. There was moderate evidence for a relationship between the presence of bacteria and both low back pain with disc herniation and Modic Type 1 change associated with disc herniation and modest evidence for causation. However, further work is needed to determine whether these organisms are a result of contamination or represent low grade infection of the spine which contributes to chronic low back pain.

Association between index-to-ring finger length ratio and risk of severe knee and hip osteoarthritis requiring total joint replacement.

OBJECTIVE: The data are conflicting for the association between the index-to-ring finger length ratio (2D:4D) and the risk of OA. The aim of this cohort study was to examine the relationship between 2D:4D and the risk of severe knee and hip OA requiring total joint replacement. METHODS: A total of 14 511 participants in the Melbourne Collaborative Cohort Study had 2D:4D assessed from hand photocopies. The incidence of total knee replacement and total hip replacement between 2001 and 2011 was determined by linking the cohort records to the Australian Orthopaedic Association National Joint Replacement Registry. RESULTS: Over an average 10.5 years of follow-up, 580 participants had total knee replacement and 499 had total hip replacement. Greater right 2D:4D [hazard ratio (HR) 0.91 for a s.d. increase in 2D:4D, 95% CI 0.84, 0.99, P = 0.03] and average right and left 2D:4D (HR 0.91 for a s.d. increase in 2D:4D, 95% CI 0.84, 0.99, P = 0.02) were associated with a reduced incidence of total knee replacement. These associations persisted when participants whose fingers had any features that might have affected the validity of 2D:4D measurements were excluded. No significant associations were observed between 2D:4D and the incidence of total hip replacement. CONCLUSION: A lower 2D:4D is associated with an increased risk of severe knee OA requiring total knee replacement, but not the risk of severe hip OA. The underlying mechanisms for the association warrant further investigation.

Associations Between Blood Concentrations of Sex Hormones and Physical Function in Community-Dwelling Older Women: A Prospective Cohort Study.

BACKGROUND: Blood concentrations of testosterone and estrone tend to increase in women aged ≥70 years, whereas concentrations of their precursor hormone dehydroepiandrosterone decline. It is unknown whether these changes influence physical function. We investigated whether concentrations of these hormones were associated with grip strength and self-reported physical function in community-dwelling older women. METHODS: A total of 9 179 Australian women, aged ≥70 years, were recruited to the ASPirin in Reducing Events in the Elderly (ASPREE) trial. Sex hormones were measured in Sex Hormones in Older Women, an ASPREE substudy, by liquid chromatography-tandem mass spectrometry in 6 358 women. The associations between hormone concentrations and physical function (handgrip strength and self-reported physical function assessed by SF-12v2 physical component summary [PCS]) were examined using multiple linear regression. RESULTS: The median age of the 5,447 participants was 74.0 (interquartile range 71.7-77.6) years. Testosterone concentrations above the lowest quartile were associated with less decline in grip strength (mean -1.39 [95% CI -1.54 to -1.24] vs -1.75 [-2.00 to -1.50] kg, p = .02), and dehydroepiandrosterone concentrations above the lowest quartile were associated with less decline in grip strength (-1.39 [-1.54 to -1.25] vs -1.82 [-2.11 to -1.55] kg, p = .007) and PCS scores (-1.49 [-1.80 to -1.17] vs -2.33 [-2.93 to -1.72], p = .02) over 4 years, compared with those in the respective lowest quartile. CONCLUSIONS: Low endogenous concentrations of testosterone and dehydroepiandrosterone were associated the greatest likelihood of physical function decline in community-based women aged ≥70 years. Further studies are warranted to determine whether testosterone and dehydroepiandrosterone therapy prevent functional decline in this at-risk group using sensitive measures of muscle strength and performance.

Sex-dependent associations of plasma high-density lipoprotein cholesterol and mortality risk in healthy older men and women: two prospective cohort studies.

The relationship between high plasma high-density lipoprotein cholesterol (HDL-C) and cause and mortality are not well established in healthy older people. This study examined the associations between HDL-C levels and mortality in initially healthy older men and women. This analysis included participants from the Aspirin in Reducing Events in the Elderly (ASPREE; n=18,668) trial and a matched cohort from the UK Biobank (UKB; n=62,849 ≥65 years). Cox regression was used to examine hazard ratios between HDL-C categories <1.03 mmol/L, 1.03-1.55 mmol/L (referent category), 1.55-2.07 mmol/L, and >2.07 mmol/L and all-cause, cancer, cardiovascular disease (CVD), and "non-cancer non-CVD" mortality. Genetic contributions were assessed using a polygenic score for HDL-C. Among ASPREE participants (aged 75±5 years), 1836 deaths occurred over a mean follow-up of 6.3±1.8 years. In men, the highest category of HDL-C levels was associated with increased risk of all-cause (HR 1.60, 95% CI 1.26-2.03), cancer (HR 1.37, 95% CI 0.96-2.00), and "non-cancer non-CVD" mortality (HR 2.35, 95% CI 1.41-3.42) but not CVD mortality (HR 1.08, 95% CI 0.60-1.94). The associations were replicated among UKB participants (aged 66.9±1.5 years), including 8739 deaths over a mean follow-up of 12.7±0.8 years. There was a non-linear association between HDL-C levels and all-cause and cause-specific mortality. The association between HDL-C levels and mortality was unrelated to variations in the HDL-C polygenic score. No significant association was found between HDL-C levels and mortality in women. Higher HDL-C levels are associated with increased risk from cancer and "non-cancer non-CVD" mortality in healthy older men but no such relationship was observed in women.

Association of plasma high-density lipoprotein cholesterol level with risk of incident dementia: a cohort study of healthy older adults.

Background: Recent studies have reported associations between high plasma high-density lipoprotein cholesterol (HDL-C) levels and risk of all-cause mortality, age-related macular degeneration, sepsis and fractures, but associations with dementia risk remain unclear. To determine whether high plasma HDL-C levels are associated with increased incident dementia risk in initially-healthy older people. Methods: We conducted a post-hoc analysis of the Aspirin in Reducing Events in the Elderly (ASPREE) trial; a double-blind, randomized, placebo-controlled trial of daily low-dose aspirin in healthy older people. ASPREE recruited 16,703 participants aged ≥70 years (from Australia) and 2411 participants aged ≥65 years (from the US) between 2010 and 2014. Participants had no diagnosed cardiovascular disease, dementia, physical disability, or life-threatening illness at enrolment and were cognitively healthy (3MS score ≥78). All-cause dementia was a primary trial endpoint, and determined by DSM-IV criteria. Cox regression was used to examine hazard ratios between HDL-C categories <40 mg/dL, 40-60 mg/dL (reference category), 60-80 mg/dL, and >80 mg/dL and dementia. Restricted cubic spline curves were used to determine nonlinear associations. Data analysis was performed from October 2022 to January 2023. Findings: Of the 18,668 participants, 850 (4.6%) cases of incident dementia were recorded over 6.3 (SD 1.8) years. Participants with high HDL-C (>80 mg/dL) had a 27% higher risk of dementia (HR 1.27, 95% CI 1.03, 1.58). Age stratified analyses demonstrated that the risk of incident dementia was higher in participants ≥75 years compared to participants <75 years (HR 1.42, 95% CI 1.10, 1.83 vs HR 1.02, 95% CI 0.68, 1.51). Associations remained significant after adjusting for covariates including age, sex, country of enrolment, daily exercise, education, alcohol consumption, weight change over time, non-HDL-C, HDL-C-PRS, and APOE genotype. Interpretation: In a population of initially-healthy older adults aged ≥75 years, high HDL-C levels were associated with increased risk of all-cause dementia. Funding: National Institutes of Health, USA; National Health and Medical Research Council Australia; Monash University (Melbourne, VIC, Australia); and the Victorian Cancer Agency (Australia).

Testosterone and the risk of incident atrial fibrillation in older men: further analysis of the ASPREE study.

Background: A cardiovascular safety trial of testosterone in men with cardiovascular risk factors or disease found no difference in rates of major adverse cardiovascular events (MACE) or death but noted more atrial fibrillation (AF) events in testosterone-treated men. We investigated the relationship between endogenous testosterone concentrations with risk of developing AF in healthy older men. Methods: Post-hoc analysis of 4570 male participants in the ASPirin in Reducing Events in the Elderly (ASPREE) study. Men were aged ≥ 70 years, had no history of cardiovascular disease (including AF), thyroid disease, prostate cancer, dementia, or life-threatening illnesses. Risk of AF was modelled using Cox proportional hazards regression. Findings: Median (IQR) age was 73.7 (71.6-77.1) years and median (IQR) follow-up 4.4 (3.3-5.5) years, during which 286 men developed AF (15.3 per 1000 participant-years). Baseline testosterone was higher in men who developed incident AF compared men who did not [17.0 (12.4-21.2) vs 15.7 (12.2-20.0) nmol/L]. There was a non-linear association of baseline testosterone with incident AF. The risk for AF was higher in men with testosterone in quintiles (Q) 4&5 (Q4:Q3, HR = 1.91; 95%CI = 1.29-2.83 and Q5:Q3HR = 1.98; 95%CI = 1.33-2.94). Results were similar after excluding men who experienced MACE or heart failure during follow-up. Interpretation: Circulating testosterone concentrations within the high-normal range are independently associated with an increased risk of incident AF amongst healthy older men. This suggests that AF may be an adverse consequence of high-normal total testosterone concentrations. Funding: National Institute on Aging and National Cancer Institute at the National Institutes of Health; Australian Government (NHMRC, CSIRO); Monash University; and AlfredHealth.

Association of serum phosphate, calcium and alkaline phosphatase with risk of incident fractures in healthy older adults.

BACKGROUND: Aging increases fracture risk through bone loss and microarchitecture deterioration due to an age-related imbalance in bone resorption and formation during bone remodelling. We examined the associations between levels of phosphate, calcium, and alkaline phosphatase, and fracture risk in initially-healthy older individuals. METHODS: A post-hoc analysis of the Aspirin in Reducing Events in the Elderly (ASPREE) trial recruited 16,703 Australian participants aged ≥70 years and 2,411 US participants aged ≥65 years. Analyses were conducted on ASPREE-Fracture substudy participants from Australia with serum calcium, phosphate, and alkaline phosphatase measurement. Fracture data were collected post-randomization. Cox regression was used to calculate hazard ratios (HR) and 95% confidence intervals (CIs). Phosphate, calcium, and alkaline phosphatase were analysed in deciles (D1-D10), with deciles 4-7 (31-70%) as the reference category. Restricted cubic spline curves were used to identify nonlinear associations. RESULTS: Of the 9915 participants, 907 (9·2%) persons had incident fractures recorded over 3·9 (SD 1·4) years. In the fully adjusted model, males in the top decile (D10) of phosphate had 78% higher risk of incident fracture (HR 1·78, 95% CI 1·25-2·54). No such association was observed for females (HR 1·09, 95% CI 0·83-1·44). The population attributable fraction in men within the D10 phosphate category is 6·9%. CONCLUSION: This result confirms that, high-normal serum phosphate levels are associated with increased fracture risk in older men.