Reduced rates of primary joint replacement for osteoarthritis in Italian and Greek migrants to Australia: the Melbourne Collaborative Cohort Study

Association of 4p14 TLR locus with antibodies to Helicobacter pylori

A genome-wide association study among Europeans related polymorphisms of the Toll-like receptor (TLR) locus at 4p14 and the Fcγ receptor 2a locus at 1q23.3 to Helicobacter pylori serologic status. We replicated associations of 4p14 but not 1q23.3 with anti-Helicobacter pylori antibodies in 1402 Finnish males. Importantly, our analysis clarified that the phenotype affected by 4p14 is quantitative level of these antibodies rather than association with seropositivity per se. In addition, we annotated variants at 4p14 as expression quantitative trait loci (eQTL) associated with TLR6/10 and FAM114A1. Our findings suggest that 4p14 polymorphisms are linked to host immune response to H. pylori infection but not to its acquisition.

Associations between socioeconomic status and primary total knee joint replacements performed for osteoarthritis across Australia 2003-10: data from the Australian Orthopaedic Association National Joint Replacement Registry

Background

Relatively little is known about the social distribution of total knee joint replacement (TKR) uptake in Australia. We examine associations between socioeconomic status (SES) and TKR performed for diagnosed osteoarthritis 2003–10 for all Australian males and females aged ≥30 yr.

Methods

Data of primary TKR (n = 213,018, 57.4% female) were ascertained from a comprehensive national joint replacement registry. Residential addresses were matched to Australian Census data to identify area-level social disadvantage, and categorised into deciles. Estimated TKR rates were calculated. Poisson regression was used to model the relative risk (RR) of age-adjusted TKR per 1,000py, stratified by sex and SES.

Results

A negative relationship was observed between TKR rates and SES deciles. Females had a greater rate of TKR than males. Surgery utilisation was greatest for all adults aged 70-79 yr. In that age group differences in estimated TKR per 1,000py between deciles were greater for 2010 than 2003 (females: 2010 RR 4.32 and 2003 RR 3.67; males: 2010 RR 2.04 and 2003 RR 1.78).

Conclusions

Identifying factors associated with TKR utilisation and SES may enhance resource planning and promote surgery utilisation for end-stage osteoarthritis.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2474-15-356) contains supplementary material, which is available to authorized users.

Incidence of total knee and hip replacement for osteoarthritis in relation to circulating sex steroid hormone concentrations in women

OBJECTIVE

The increased prevalence of osteoarthritis (OA) in postmenopausal women suggests that changes in either circulating sex steroid concentrations or the tissue response to sex steroids may have a role in the pathogenesis of OA. The aim of this study was to examine whether circulating sex steroid concentrations are associated with the incidence of total knee and total hip replacement for OA.

METHODS

Study subjects (n = 2,621; all women) were recruited in 1990-1994 from the Melbourne Collaborative Cohort Study (MCCS). Circulating sex steroid concentrations were measured in blood samples obtained from the women at the time of recruitment. The incidence of total knee and total hip replacement for OA during 2001-2011 was determined by linking the MCCS records to the Australian Orthopaedic Association National Joint Replacement Registry.

RESULTS

During the followup period, 115 women had undergone total knee replacement and 99 had undergone total hip replacement for OA. Greater log-transformed concentrations of estradiol were associated with a lower incidence of knee replacement (hazard ratio [HR] 0.70, 95% confidence interval [95% CI] 0.50-0.96), and greater log-transformed concentrations of androstenedione were associated with a lower incidence of hip replacement (HR 0.70, 95% CI 0.52-0.93). In contrast, greater log-transformed concentrations of sex hormone binding globulin (SHBG) were associated with a higher incidence of hip replacement (HR 1.70, 95% CI 1.05-2.77).

CONCLUSION

A lower estradiol concentration is a risk factor for knee OA, while a lower androstenedione concentration and higher SHBG concentration are risk factors for hip OA in women. These findings suggest that circulating sex steroids have a role in the pathogenesis of OA, and that modifying these steroid concentrations may provide a potential strategy for the prevention and treatment of knee and hip OA.

Trends in migrant mortality rates in Australia 1981-2007: a focus on the National Health Priority Areas other than cancer

INTRODUCTION

Migrants generally have more favourable mortality outcomes than the Australian-born population. The aim of this study is to update knowledge and inform future research in this field by examining mortality from musculoskeletal conditions, asthma, cardiovascular disease, diabetes mellitus, injuries and mental conditions between 1981 and 2007 among migrants in Australia.

METHODS

Average annual sex- and age-standardised mortality rates were calculated for each migrant group, period of death registration and cause of death.

RESULTS AND CONCLUSIONS

Mortality rates decreased among most groups for asthma, cardiovascular disease and motor vehicle accidents, with rates diverging in the later time periods. The reverse was true for mental disorders, where Australian-born individuals experienced the greatest increase in mortality. Migrants generally displayed more favourable mortality outcomes than their Australian-born counterparts. Migrants from Southern Europe appeared to have the greatest advantage. However, some migrants appeared to be over-represented in the areas of diabetes, suicide and mental health.

The prevalence and risk factors of epiretinal membranes: the Melbourne Collaborative Cohort Study

PURPOSE

To determine the prevalence of epiretinal membranes (ERMs) in Melbourne, Australia and its risk factors in this population.

METHODS

The Melbourne Collaborative Cohort Study is a prospective study investigating the role of diet and life style in the causation of common chronic diseases. Eighty-six percent of participants were of Northern European origin born in Australia or United Kingdom and 14% were migrants from Greece or Italy (Southern European origin). Nonmydriatic digital retinal photography was implemented at Melbourne Collaborative Cohort Study follow-up. The ERMs were recorded as cellophane macular reflex without retinal folds or preretinal macular fibrosis (PMF) with retinal folds.

RESULTS

A total of 22,406 participants had retinal photography, 95% (n = 21,241) were eligible for ERM grading. The ERM prevalence were 8.9% (1,882); cellophane macular reflex, 4.9% (1,047); and preretinal macular fibrosis, 3.9% (835). After adjustment for age, sex, level of education, smoking status, level of cholesterol, body mass index, waist-to-hip ratio, waist measurement, blood pressure, diabetes, and stroke, increasing age and Southern European ethnicity was significantly associated with ERMs. Overall, in Southern Europeans, ERMs odd ratio was 1.97 (95% confidence intervals, 1.67-2.31), P < 0.001; preretinal macular fibrosis was 1.82 (95% confidence intervals, 1.43-2.31), P < 0.001; and cellophane macular reflex was 1.93 (1.57-2.38), P < 0.001.

CONCLUSION

In an older Australian population, the prevalence of ERMs was 8.9% and was almost two times higher in participants of Southern European origin than Northern European origin.

Total Knee Replacement as a Knee Osteoarthritis Outcome: Predictors Derived from a 4-Year Long-Term Observation following a Randomized Clinical Trial Using Chondroitin Sulfate

OBJECTIVE

To predict, using clinical and qMRI data, the incidence of total knee replacement (TKR) during the long-term follow-up of knee osteoarthritis (OA) patients who formerly received chondroitin sulfate (CS) or placebo treatment.

DESIGN

A post hoc intention-to-treat analysis to evaluate the incidence of TKR was done on knee OA patients who had participated in a 12-month trial evaluating the impact of CS (800 mg/d) versus placebo for 6 months, followed by a 6-month open-phase in which all patients received CS. Additionally, the clinical and qMRI predictors of TKR were determined.

RESULTS

Thirteen TKRs were performed in the population after a 4-year follow-up. More TKRs were performed in the placebo group than in the CS group (69% vs. 31%, P = 0.150, logistic regression). The statistically significant predictors of TKRs were, at baseline, higher WOMAC pain and function scores, presence of bone marrow lesions (BMLs), and higher C-reactive protein levels. Loss of medial cartilage volume and increase in WOMAC pain and function at one-year were also predictors of TKR. Multivariate analyses revealed that baseline presence of BML and higher WOMAC pain score were independent predictors. Time to occurrence of the TKR also favored the CS group versus placebo (log-rank, P = 0.094).

CONCLUSION

Symptoms such as knee pain and function, presence of BML, and cartilage volume loss predict the long-term occurrence of a "hard" outcome such as TKR.

Evidence-based review for patients undergoing elective hip and knee replacement

BACKGROUND

The objective of this study was to evaluate the evidence for different interventions in the preoperative, perioperative and post-operative care for people undergoing elective total hip (THR) and knee (TKR) replacement surgery.

METHOD

A multidisciplinary working group comprising consumers, managers and clinicians from the areas of orthopaedics, rheumatology, aged care and rehabilitation evaluated randomized controlled trials (RCTs) and systematic reviews/meta-analyses concerning aspects of preoperative, perioperative and post-operative clinical care periods for THR/TKR through systematic searching of Medline, Embase, CENTRAL and the Cochrane Database of Systematic Reviews from May 2007 to April 2011. Multiple reviewers determined study eligibility and one or more members extracted primary study findings. The body of evidence were assessed and specific recommendations made according to NHMRC guidelines.

RESULTS

Twenty-five aspects were identified for review. Recommendations for 16 of 25 areas of care were made: impact of waiting, multidisciplinary preparation, preoperative exercise, smoking cessation, interventions for comorbid conditions, predictors of outcome, clinical pathways, implementation of a blood management programme, antibiotic prophylaxis, regional anaesthesia and analgesia, use of a tourniquet in knee replacement, venous thromboembolism prophylaxis, early post-operative cryotherapy, early mobilization and continuous passive motion. In the post-operative period, study heterogeneity across all aspects of care precluded specific recommendations.

CONCLUSIONS

There was a deficiency in the quality of the evidence supporting key aspects of the continuum of care for primary THR/TKR surgery. Consequently, recommendations were limited. Prioritization and funding for research into areas likely to impact clinical practice and patient outcomes after elective joint replacement surgery are the next important steps.

Utilisation of primary total knee joint replacements across socioeconomic status in the Barwon Statistical Division, Australia, 2006-2007: a cross-sectional study

OBJECTIVES

There are few Australian data that examine the association between total knee joint replacement (TKR) utilisation and socioeconomic status (SES). This study examined TKR surgeries with a diagnosis of osteoarthritis (OA) performed for residents of Barwon Statistical Division (BSD) for 2006-2007.

DESIGN

Cross-sectional.

SETTING

BSD, South-eastern Victoria, Australia

PARTICIPANTS

All patients who underwent a TKR for OA, 2006-2007, and whose residential postcode was identified as within the BSD of Australia, and for whom SES data were available, were eligible for inclusion.

PRIMARY OUTCOME MEASURE

Primary TKR data ascertained from the Australian Orthopaedic Association National Joint Replacement Registry. Residential addresses were matched with the Australian Bureau of Statistics census data, and the Index of Relative Socioeconomic Disadvantage was used to determine SES, categorised into quintiles whereby quintile 1 indicated the most disadvantaged and quintile 5 the least disadvantaged. Age-specific and sex-specific rates of TKR utilisation per 1000 person-years were reported for 10-year age bands.

RESULTS

Females accounted for 62.7% of the 691 primary TKR surgeries performed during 2006-2007. The greatest utilisation rates of TKR in males was 7.6 observed in those aged >79 years, and in 10.2 in females observed in those aged 70-79 years. An increase in TKR was observed for males in SES quintile four compared to quintile 1 in which the lowest utilisation which was observed (p=0.04). No differences were observed in females across SES quintiles.

CONCLUSIONS

Further investigation is warranted on a larger scale to examine the role that SES may play in TKR utilisation, and to determine whether any social disparities in TKR utilisation reflect health system biases or geographic differences.

Cross-sectional analysis of association between socioeconomic status and utilization of primary total hip joint replacements 2006-7: Australian Orthopaedic Association National Joint Replacement Registry

BACKGROUND

The utilization of total hip replacement (THR) surgery is rapidly increasing, however few data examine whether these procedures are associated with socioeconomic status (SES) within Australia. This study examined primary THR across SES for both genders for the Barwon Statistical Division (BSD) of Victoria, Australia.

METHODS

Using the Australian Orthopaedic Association National Joint Replacement Registry data for 2006-7, primary THR with a diagnosis of osteoarthritis (OA) among residents of the BSD was ascertained. The Index of Relative Socioeconomic Disadvantage was used to measure SES; determined by matching residential addresses with Australian Bureau of Statistics census data. The data were categorised into quintiles; quintile 1 indicating the most disadvantaged. Age- and sex-specific rates of primary THR per 1,000 person years were reported for 10-year age bands using the total population at risk.

RESULTS

Females accounted for 46.9% of the 642 primary THR performed during 2006-7. THR utilization per 1,000 person years was 1.9 for males and 1.5 for females. The highest utilization of primary THR was observed in those aged 70-79 years (males 6.1, and females 5.4 per 1,000 person years). Overall, the U-shaped pattern of THR across SES gave the appearance of bimodality for both males and females, whereby rates were greater for both the most disadvantaged and least disadvantaged groups.

CONCLUSIONS

Further work on a larger scale is required to determine whether relationships between SES and THR utilization for the diagnosis of OA is attributable to lifestyle factors related to SES, or alternatively reflects geographic and health system biases. Identifying contributing factors associated with SES may enhance resource planning and enable more effective and focussed preventive strategies for hip OA.

Drivers of surgery for the degenerative hip, knee, and spine: a systematic review

BACKGROUND

Surgical treatment for degenerative conditions of the hip, knee, and spine has an impact on overall healthcare spending. Surgical rates have increased dramatically and considerable regional variation has been observed. The reasons behind these increasing rates and variation across regions have not been well elucidated.

QUESTIONS/PURPOSES

We therefore identified demographic (D), social structure (SS), health belief (HB), personal (PR) and community resources (CR), and medical need (MN) factors that drive rates of hip, knee, and spine surgery.

METHODS

We conducted a systematic review to include all observational, population-based studies that compared surgical rates with potential drivers (D, SS, HB, PR, CR, MN). We searched PubMed combining key words focusing on (1) disease and procedure; (2) study methodology; and (3) explanatory models. Independent investigators selected potentially eligible studies from abstract review and abstracted methodological and outcome data. From an initial search of 256 articles, we found 37 to be potentially eligible (kappa 0.86) but only 28 met all our inclusion criteria.

RESULTS

Age, nonminority, insurance coverage, and surgeon enthusiasm all increased surgical rates. Rates of arthroplasty were higher for females with higher education, income, obesity, rurality, willingness to consider surgery, and prevalence of disease, whereas spinal rates increased with male gender, lower income, and the availability of advanced imaging.

CONCLUSIONS

Regional variation in these procedures exists because they are examples of preference-sensitive care. With strategies that may affect change in factors that are potentially modifiable by behavior or resources, extreme variation in rates may be reduced.

Burden of restraint, disablement, and ethnic identity: a case study of total joint replacement for osteoarthritis

Health disparities in total joint replacement have been documented based on gender and ethnicity in multiple countries. Absent are studies exploring the meaning of the procedures among diverse women, which is necessary to fully understand the impact of the disparity. Drawing on ethnographic data from a life course exploration of disablement among Mexican American women with mobility impairments, one woman's reasons for forgoing a joint replacement are considered. It is suggested that inequalities in disablement cannot be understood without considering the multiple cultural conflicts and loyalties that push and pull women in multiple directions.

Breakout session: Ethnic and racial disparities in joint arthroplasty

BACKGROUND

Many authors report racial and ethnic disparities in total joint arthroplasty. The extent and implications, however, are not fully understood.

QUESTIONS/PURPOSES

Our purposes in this breakout session were to (1) define "Where are we now?"; (2) outline "Where do we need to go?"; and (3) generate a plan for "How do we get there?" in addressing issues of racial disparity and total joint arthroplasty. WHERE ARE WE NOW?: Blacks and some other ethnic minorities have a greater incidence of arthritis and chronic disability than the population in general. Blacks have a lower use of total joint arthroplasty for a variety of reasons, including patient trust, perceived limited satisfaction with results by peers, varying knowledge about total joint arthroplasty, and concerns about pain associated with these procedures. Current data, however, are insufficient to clearly define the magnitude and nature of musculoskeletal disparities. WHERE DO WE NEED TO GO?: We need to better define the magnitude and nature of racial disparities to best design and implement research questions and studies and target areas for improvement. We should define geographic and provider variation that lead to the differences in use that has been observed in total joint arthroplasty. HOW DO WE GET THERE?: A profession-wide emphasis and focus on disparities needs to be developed with other medical specialties and national organizations to advocate for changes to better define and address racial disparities. Partnerships with organizations and/or investigators that can gain access to relevant databases should be encouraged. Special attention to disparities and manuscript reviewing and editing is essential.

Ethnic and gender differences in the functional disparities after primary total knee arthroplasty

BACKGROUND

The benefits of TKA have been well documented. Whether these benefits apply equally across gender and ethnic groups is unclear. Given the underuse of TKA among certain demographic groups, it is important to understand whether gender or ethnicity influence pain and function after TKA.

QUESTIONS/PURPOSES

We determined (1) the influence of race, gender, and body mass index (BMI) on primary TKA functional scores and ROM before gender-specific implants; and (2) whether comorbidities influenced ROM and functional scores.

PATIENTS AND METHODS

We reviewed all 202 patients who underwent primary TKAs in 2004. We contacted 185 of the 202 patients, including 90 African-Americans, 87 Caucasians, four Asians, and four Hispanics (55 men, 130 women). Their average age was 66 years, and average BMI was 34.4 (range, 20-55). Knee Society scores (KSS) and ROM, patient demographics, and the Charlson Comorbidity Index (CCI) were recorded. Minimum followup was 24 months (average, 29.1 months; range, 24-60.3 months).

RESULTS

African-Americans had longer delays to presentation, higher BMI, and worse 2-year KSS. Women (all races) had higher BMI and worse preoperative flexion/arc ROM. African-American women had worse final ROM and had similar final gains in ROM (postoperative minus preoperative ROM) after controlling for confounders.

CONCLUSIONS

Gender and race affected functional KSS and ROM variables. The worse results experienced by African-American women may be attributable to a longer delay to presentation. However, the scores and motion were high for all subgroups, and underuse of TKA in women and African-Americans cannot be justified based on a perception of lesser functional gains.

Variation in rates of hip and knee joint replacement in Australia based on socio-economic status, geographical locality, birthplace and indigenous status

BACKGROUND

Our understanding of the incidence of joint replacement across different subgroups of the Australian population is limited. This study investigated whether rates of hip and knee joint replacement vary according to socio-economic status, geographical locality, birthplace and indigenous status.

METHODS

Data from the National Hospital Morbidity Database were obtained. All separations for primary hip or knee joint replacement with the principal diagnosis of arthritis were identified. Age-standardized procedure rates were compared based on socio-economic status, geographical locality, birthplace and indigenous status.

RESULTS

Compared with age- and gender-matched individuals, rates of joint replacement overall were significantly lower in people living in the most disadvantaged (P < 0.05) and remote areas (P < 0.001), people born outside Australia (P < 0.05) and indigenous people (P < 0.001). However, there were some exceptions. Knee replacement rates were higher in the most disadvantaged areas than in the least disadvantaged areas (P < 0.01), and both hip and knee replacement rates were higher in regional areas than in major cities (P < 0.05). Males and females born in New Zealand and females born in the United Kingdom, Ireland and parts of Europe had a greater rate of hip replacement, and females from North Africa and the Middle East had a greater rate of knee replacement, than Australia-born people (P < 0.001).

CONCLUSIONS

There is significant variation in the rates of primary total hip and knee replacement in Australia. Further investigation is needed to determine whether this simply reflects patterns of disease and disease risk factors, or is because of inequalities in health care, unmet need, and/or surgical or patient-related factors.

Migration and health in Canada: health in the global village

BACKGROUND

Immigration has been and remains an important force shaping Canadian demography and identity. Health characteristics associated with the movement of large numbers of people have current and future implications for migrants, health practitioners and health systems. We aimed to identify demographics and health status data for migrant populations in Canada.

METHODS

We systematically searched Ovid MEDLINE (1996-2009) and other relevant web-based databases to examine immigrant selection processes, demographic statistics, health status from population studies and health service implications associated with migration to Canada. Studies and data were selected based on relevance, use of recent data and quality.

RESULTS

Currently, immigration represents two-thirds of Canada's population growth, and immigrants make up more than 20% of the nation's population. Both of these metrics are expected to increase. In general, newly arriving immigrants are healthier than the Canadian population, but over time there is a decline in this healthy immigrant effect. Immigrants and children born to new immigrants represent growing cohorts; in some metropolitan regions of Canada, they represent the majority of the patient population. Access to health services and health conditions of some migrant populations differ from patterns among Canadian-born patients, and these disparities have implications for preventive care and provision of health services.

INTERPRETATION

Because the health characteristics of some migrant populations vary according to their origin and experience, improved understanding of the scope and nature of the immigration process will help practitioners who will be increasingly involved in the care of immigrant populations, including prevention, early detection of disease and treatment.