Physician-diagnosed Osteoarthritis Research Articles

Prevalence of and factors associated with osteoarthritis and pain in retired Olympians compared with the general population: part 2 – the spine and upper limb

Objectives(1) To determine the prevalence of spine and upper limb osteoarthritis (OA) and pain in retired Olympians; (2) identify risk factors associated with their occurrence and (3) compare with a...

Prevalence of and factors associated with osteoarthritis and pain in retired Olympians compared with the general population: part 1 – the lower limb

ObjectivesThis study aims (1) to determine the prevalence of lower limb osteoarthritis (OA) and pain in retired Olympians; (2) to identify factors associated with their occurrence and (3) to compare...

Projected number of osteoarthritis patients in Austria for the next decades \u2013 quantifying the necessity of treatment and prevention strategies in Europe

BackgroundThe present study aimed to predict the expected number of patients with osteoarthritis (OA) in Austria up to the year 2080.MethodsDemographic data and population projections between 2019 and 2080 were obtained from European authorities. Information about recent age- and sex-stratified prevalence of patients with self-reported physician-diagnosed OA was obtained from the Austrian Health Interview Survey (n = 15,771). Projections were stratified by age and sex; sensitivity analyses were performed based on aging, main (most likely), and growth scenarios of the population.ResultsBased on the projection, the overall increase in the total number of patients with OA from 2019 to 2080 will be 38% for men and women. In 2019, the highest number of OA-patients nested in the groups of persons aged 70-79 (n = 238,749) and 60-69 (n = 237,729) years. In 2080, the 80+ age group is predicted to have the highest number of OA with 421,548 individuals (i.e. factor 3.45 and factor 2.48 increase in the male and female group, respectively, compared to 2019), followed by the group aged 70-79 with 314,617 individuals (factor 1.45 and factor 1.28 increase in the male and female group, respectively, compared to 2019). Similar trends were found in the ageing and growing scenarios.ConclusionsThe projected increase in the occurrence of OA will likely lead to a substantial socioeconomic burden for the Austrian healthcare system in the near and far future. The current findings plead for the development of sustainable concepts for the treatment and prevention of OA by European authorities.

Factors Influencing Quality of Life Among Older Persons Living With Osteoarthritis Using 3 Different Definitions

Aim: While the impact of osteoarthritis (OA) on the older person's quality of life (QoL) has been established, the associations are complicated by numerous potential mediators and variations in diagnostic criteria. This study was conducted to explore the relationship between OA and QoL and the influence of physical performance, symptoms severity, and psychological factors on this potential relationship using 3 different methods of identification of OA. Methods: This cross-sectional study used data from the Malaysian Falls Assessment and Intervention Trial study. Radiological OA (ROA), clinical OA (COA), or self-reported physician-diagnosed OA (SOA) was determined using established criteria. Quality of life was measured with the 19-item Control, Autonomy, Self-Realization and Pleasure (CASP-19) questionnaire. Results: Of 370 participants (219 fallers, 151 nonfallers), mean (SD) age = 73.71 (6.57) years, COA (odds ratio [OR] 95% confidence interval [CI]; 1.38 [0.64-2.94]) and SOA (1.84 [1.19-2.84]) were associated with CASP-19 of 47 and less but not ROA. The association between SOA and CASP-19 of 47 and less was attenuated by physical performance while COA was no longer associated with CASP-19 of 47 and less after adjustment for psychological status. Conclusion: Our findings hold important clues to unraveling factors that influence QoL in older adults with OA and will inform future intervention studies aimed at reducing the burden of OA among older adults.

Prevalence of joint-specific osteoarthritis and joint pain in British Columbia, Canada.

The objective is to determine the prevalence of self-reported physician-diagnosed osteoarthritis (OA) and musculoskeletal symptoms (pain, stiffness or discomfort) in specific joints among adults in British Columbia (BC), Canada. We carried out a cross-sectional mixed-mode survey in a random population sample of persons 18years of age and older. Estimates were weighted to reflect the age and sex distribution of the population of BC. We obtained responses from 2,233 individuals. Overall, 18.4% (95% CI 16.8-20.1) of the adult population reported OA. Of those, more than 40% had OA in multiple sites. Prevalence ranged from 8.8% (95% CI 7.6-10.1) in the knee to 2.7% (2.1-3.5) in the foot. One-year prevalence of symptoms ranged from 49.1% (47.0-51.2) in the lower back to 23.3% (21.5-25.1) in the hip. Females reported more symptoms and OA than males in all joints. The most common site of self-reported physician-diagnosed OA in BC is the knee, but OA in the hands, hips, and feet is also common. Having OA in one joint is a strong predictor of OA in other joints.

A Cross-Sectional Study of Retired Great British Olympians (Berlin 1936\u2013Sochi 2014): Olympic Career Injuries, Joint Health in Later Life, and Reasons for Retirement from Olympic Sport

BackgroundThe relationship between Olympic career sport injury and the long-term musculoskeletal health of the elite athlete remains unclear. This study describes the lifetime prevalence of medical attention injuries that occurred during training and/or competition as part of the athlete’s Olympic career, reasons for retirement from Olympic sport, and the point prevalence of pain and osteoarthritis (OA) among retired Great Britain’s (GB) Olympians.MethodsThis cross-sectional study involved distributing a questionnaire to retired GB Olympians who had competed at 36 Olympic Games between Berlin 1936 and Sochi 2014. The questionnaire captured Olympic career injury history (lasting ≥ 1 month), sport exposure, musculoskeletal pain (last 4 weeks), physician-diagnosed OA, and joint replacement. Injury prevalence was calculated for sports with a minimal of 15 respondents. Adjusted odds ratios (aOR) were estimated in logistic regression for pain, OA, and joint replacement. Models were adjusted for age, sex, BMI, and career duration.ResultsSix hundred fifty (57.8% male; 42.2% female) retired athletes representing 40 sports (29 summer; 11 winter), aged 60.5 years (range 23–97), completed the questionnaire. Overall, 721 injuries (368 athletes) were self-reported equating to a lifetime Olympic career injury prevalence of 56.6%. Injury prevalence was highest in field athletics (81.0%), gymnastics (75.0%), and track athletics (67.7%). Injuries most frequently occurred at the knee (19.0%), lower back (15.4%), and shoulder (11.5%). Of those injured, 19.5% retired from sport due to injury. Pain was most prevalent at the lumbar spine (32.8%), knee (25.3%), and hip (22.5%), and OA at the knee (13.4%), hip (10.4%), and lumbar spine (4.6%). Injury was associated with pain at the hip (aOR 4.88; 95% CI, 1.87–12.72, p = 0.001), knee (aOR 2.35; 95% CI, 1.45–3.81, p = 0.001), and lumbar spine (aOR 2.53; 95% CI, 1.63–3.92, p < 0.001); OA at the hip (aOR 5.97; 95% CI, 1.59–22.47, p = 0.008) and knee (aOR 3.91; 95% CI, 2.21–6.94, p < 0.001); and joint replacement at the hip (aOR 8.71; 95% CI, 2.13–35.63, p = 0.003) and knee (aOR 5.29; 95% CI, 2.39–11.74, p < 0.001).ConclusionThe lifetime prevalence of Olympic career injury was 56.6%, with those injured more likely to self-report current pain and/or OA at the hip, knee, and lumbar spine and joint replacement at the hip and knee.

Moderate to Severe Osteoarthritis Pain and Its Impact on Patients in the United States: A National Survey.

PurposeOsteoarthritis (OA) is one of the most common causes of chronic pain and a leading cause of disability in the US. The objective of this study was to examine the clinical and economic burden of OA by pain severity.Patients and MethodsWe used nationally representative survey data. Adults ≥18 years with self-reported physician-diagnosed OA and experiencing OA pain were included in the study. OA pain severity was measured using the Short Form McGill Pain Questionnaire Visual Analog Scale (SF-MPQ-VAS). Data were collected for demographics, clinical characteristics, health-related quality of life (HRQoL), productivity, OA treatment, adherence to pain medication, and healthcare resource utilization. Univariate analysis was performed to examine differences between respondents with moderate-to-severe OA pain vs those with mild OA pain.ResultsHigher proportions of respondents with moderate-to-severe OA pain (n=3798) compared with mild OA pain (n=2038) were female (69.4% vs 57.3%), <65 years of age (54.8% vs 43.4%), and not employed (70.6% vs 64.5%). Respondents with moderate-to-severe OA pain experienced OA pain daily (80.8% vs 48.8%), were obese (53.0% vs 40.5%), had more comorbidities (sleep disturbance, insomnia, depression, and anxiety), and reported significantly poorer health status and HRQoL, and greater productivity and activity impairment (all P<0.05). Moderate-to-severe OA pain respondents were prescribed significantly more pain medications than mild OA pain respondents (41.0% vs 17.0%) and had higher adherence (75.9% vs 64.1%) yet were less satisfied with their pain medications (all P<0.001). Outpatient and emergency room visits, and hospitalizations in the 6 months prior to the survey were significantly higher in moderate-to-severe OA pain respondents vs those with mild OA pain (all P<0.05).ConclusionPatient and clinical burden was significantly greater in moderate-to-severe OA pain respondents vs mild OA pain respondents and may inform decision-making for appropriate resource allocation and effective management strategies that target specific subgroups.

Are pain severity and current pharmacotherapies associated with quality of life, work productivity, and healthcare utilisation for people with osteoarthritis in five large European countries?

Although the osteoarthritis (OA) burden is well-recognised, the benefit of currently available OA pharmacological therapy is not clear. This study aimed to assess whether the impact of OA pain on health-related quality of life (HRQoL), work, and healthcare resource utilisation (HRU) differed by both pain severity and prescription medication status. This cross-sectional study used pooled data from the 2016/2017 European National Health and Wellness Survey. Respondents with self-reported physician-diagnosed OA and pain were included. Outcomes examined included HRQoL, health utility, health status, work productivity and activity impairment, and HRU. Groups derived from self-reported pain severity and prescription medication use were compared using chi-square tests, analysis of variance, and generalised linear models controlling for socio-demographics, health behaviours, and health status. Respondents with OA (n=2417) reported mild (40.4%, of which 44.9% prescription-treated) and moderate to severe pain (59.6%, of which 54.0% prescription-treated). HRQoL, health utility, health status, and work and activity impairment were substantially worse among the moderate/severe pain prescription-treated group compared to the rest (e.g. SF-12v2 physical component score [PCS] for moderate/severe pain prescription-treated=34.5 versus mild pain prescription-treated =39.3, moderate/severe pain prescription-untreated=40.6, and mild pain prescription-untreated=45.6; p<0.01). HRU such as the mean number of emergency room visits for >6 months was higher in the prescription-treated groups (0.51-0.52, 95% CI 0.437-0.71) than the prescription-untreated groups (0.30-0.34, 95% CI 0.21-0.46; p<0.05). Persons with moderate to severe OA pain treated with available prescription medications have poor health status and HRQoL and increased HRU compared to those not receiving prescription medications.

Playing sport injured is associated with osteoarthritis, joint pain and worse health-related quality of life: a cross-sectional study

BackgroundSports participants are faced with the decision to continue or cease play when injured. The implications of playing sport while injured on joint health and health-related quality of life (HRQoL) has not been investigated. The purpose of this study was to investigate the relationship between having played sport while injured and HRQoL, osteoarthritis, and persistent joint pain; and compare findings in elite and recreational cricketers.MethodsThe Cricket Health and Wellbeing Study cohort was used for this study. Inclusion criteria were: age ≥ 18 years, played ≥1 cricket season. Questionnaire data collected included a history of playing sport injured, SF-8 (physical (PCS) and mental (MCS) component scores), physician-diagnosed osteoarthritis, and persistent joint pain (most days of the last month). Multivariable linear regressions and logistic regressions were performed. Continuous covariates were handled using fractional polynomials. Models were adjusted for age, sex, cricket-seasons played, playing status, joint injury, and orthopaedic surgery. All participants (n = 2233) were included in HRQoL analyses, only participants aged ≥30 years (n = 2071) were included in osteoarthritis/pain analyses.ResultsOf the 2233 current and former cricketers (mean age: 51.7 SD 14.7, played 30 IQR 24 cricket seasons, 60% were current cricketers, 62% played recreationally; median PCS: 51.4 IQR 9.0; MCS: 54.3 IQR 8.6) 1719 (77%) had played sport while injured. People who had played sport injured reported worse adjusted PCS (Effect(95% CI): − 1.78(− 2.62, − 0.93) and MCS (− 1.40(− 2.25, − 0.54), had greater odds of osteoarthritis (adjusted OR(95% CI): 1.86(1.39, 2.51) and persistent joint pain (2.34(1.85, 2.96)), compared to people who had not played sport injured. Similar relationships were observed regarding PCS, osteoarthritis and pain in elite and recreational subgroups. Playing injured was only related to worse MCS scores for elite cricketers (− 2.07(− 3.52, − 0.63)); no relationship was observed in recreational cricketers (− 0.70(− 1.79, 0.39)).ConclusionCricketers that had played sport injured had impaired HRQoL, increased odds of osteoarthritis and persistent joint pain, compared to those who had not played sport injured. Playing sport injured was only related to impaired mental-components of HRQoL in elite cricketers. The long-term impact of playing while injured on musculoskeletal health, should be considered when advising athletes on their ability to compete following injury.

Relationship of Occupational Category With Risk of Physical and Mental Health Problems.

ObjectivesWe evaluated the physical and mental health problems of waged workers in Korea who had different classes of occupation.MethodsWe used data from the Korean National Health and Nutrition Examination Survey (2007–2017) to examine 22,788 workers who were waged employees and categorized these workers into 5 occupational classes.Results“Unskilled manual workers” were more likely to be older, less educated, have lower monthly income, and work fewer hours per week. Among men and relative to “managers and professionals” (reference group), “skilled manual workers” were more likely to have physician-diagnosed osteoarthritis, “clerks” were less likely to report suicidal ideation, and “unskilled manual workers” were more likely to report suicidal ideation. Among women and relative to “managers and professionals” (reference group), “service and sales workers” and “unskilled manual workers” were more likely to report physician-diagnosed osteoarthritis, depressive feelings, and suicidal ideation. However, hypertension, hyperlipidemia, diabetes, and cardiovascular diseases did not differ among the occupational classes for men and women.ConclusionWe identified differences between men and women and among those in different occupational classes regarding employment status, physical health, and mental health. “Unskilled manual workers” of both genders were more likely to be older, less educated, have less monthly income, work fewer hours per week, and have suicidal ideation. Female “service and sales workers” were more likely to have osteoarthritis, depressive feelings, and suicidal ideation.

The prevalence of hand and wrist osteoarthritis in elite former cricket and rugby union players

ObjectivesThis study aimed to determine the prevalence of hand and wrist osteoarthritis in former elite cricket and rugby union players, by sport and playing position, and to define the prevalence of severe hand injury, and its association with hand osteoarthritis. DesignCross-sectional. MethodsData from cross-sectional studies of former elite male cricket and rugby players were used to determine the prevalence of hand pain, physician-diagnosed osteoarthritis, and previous severe injury. Multivariable logistic regression was used to determine the association of previous injury with pain and osteoarthritis. ResultsData from 200 cricketers and 229 rugby players were available. Complete case analysis resulted in 127 cricketers and 140 rugby players. Hand pain was more prevalent amongst cricketers (19.7%) than rugby players (10.0%). The prevalence did not differ between cricket and rugby players for hand osteoarthritis (2.4% and 3.6%), wrist osteoarthritis (1.6% and 2.1%), or previous severe hand injury (36.2% and 31.4%). No significant association between previous hand injury and pain or osteoarthritis was identified in either sport. ConclusionsFormer elite cricketers reported more hand pain than rugby players. No significant association was found between self-reported severe injury and hand osteoarthritis in either cohort, potentially indicating that risk factors aside from injury may be more prominent in the development of hand osteoarthritis.

The impact of social interactions and pain on daily positive and negative affect in adults with osteoarthritis of the knee

This study utilized experience sampling methodology (ESM) to examine the relationship of social interactions with daily pain and mood symptoms in people with osteoarthritis (OA) of the knee. Two hundred sixty-eight adults with physician-diagnosed OA of the knee underwent a baseline in-person interview and subsequent week-long ESM protocol to assess their daily activity patterns, pain, and mood via phone interview four times a day. A coding system was developed to assess presence and type of social interactions based on subject self-report of activity patterns. Multilevel modeling was used to examine between- and within-subject variation in outcomes based on both global and momentary measures of social activities, pain, and mood, while controlling for key demographic and potentially confounding variables. Positive associations were demonstrated between the ratio of positive to negative affect and both global (β = 0.49, p < .001) and momentary, especially positive (β = 0.24, p < .05), social activity patterns. Additionally, the association between negative affect and pain (β = −0.07, p < .01) was attenuated in those with more baseline social interactions. Social interaction has the potential to influence mood in adults with OA of the knee, both on a global scale, and through daily variations in interactions. These interactions seem to be directly related to mood, as well as the apparently attenuating the relationship between pain and depression. Daily social interactions showed a robust positive association with contemporaneous positive affect.

PREVENTATIVE RISK FACTORS FOR OSTEOARTHRITIS IN GREAT BRITAIN'S OLYMPIANS

BackgroundRelatively little is known about the risk factors associated with osteoarthritis (OA) in Olympic athletes. As the first step towards prevention, knowledge of preventative/modifiable risk factors are needed.ObjectiveTo examine injury...

THU0219 Prevalence of Joint Pain and Self-Reported Osteoarthritis in British Columbia, Canada

BackgroundSurvey data provide important information on the prevalence of chronic conditions across different areas and population groups. In Canada, large national surveys routinely ask about physician-diagnosed arthritis. However, population data...

Effects of Running and Walking on Osteoarthritis and Hip Replacement Risk

Running and other strenuous sports activities are purported to increase osteoarthritis (OA) risk, more so than walking and less-strenuous activities. Analyses were therefore performed to test whether running, walking, and other exercise affect OA and hip replacement risk and to assess the role of body mass index (BMI) in mediating these relationships. In this article, we studied the proportional hazards analyses of patients' report of having physician-diagnosed OA and hip replacement versus exercise energy expenditure (METs). Of the 74,752 runners, 2004 reported OA and 259 reported hip replacements during the 7.1-yr follow-up; whereas of the 14,625 walkers, 696 reported OA and 114 reported hip replacements during the 5.7-yr follow-up. Compared with running <1.8 MET · h · d(-1), the risks for OA and hip replacement decreased as follows: 1) 18.1% (P = 0.01) and 35.1% (P = 0.03) for the 1.8- and 3.6-MET · h · d(-1) run, respectively; 2) 16.1% (P = 0.03) and 50.4% (P = 0.002) for the 3.6- and 5.4-MET · h · d(-1) run, respectively; and 3) 15.6% (P = 0.02) and 38.5% (P = 0.01) for the ≥ 5.4-MET · h · d(-1) run, suggesting that the risk reduction mostly occurred by 1.8 MET · h · d(-1). Baseline BMI was strongly associated with both OA (5.0% increase per kilogram per square meter, P = 2 × 10(-8)) and hip replacement risks (9.8% increase per kilogram per square meter, P = 4.8 × 10(-5)), and adjustment for BMI substantially diminished the risk reduction from running ≥ 1.8 MET · h · d(-1) for OA (from 16.5%, P = 0.01, to 8.6%, P = 0.21) and hip replacement (from 40.4%, P = 0.005, to 28.5%, P = 0.07). The reductions in OA and hip replacement risk by exceeding 1.8 MET · h · d(-1) did not differ significantly between runners and walkers. Other (nonrunning) exercise increased the risk of OA by 2.4% (P = 0.009) and hip replacement by 5.0% per MET · h · d(-1) (P = 0.02), independent of BMI. Running significantly reduced OA and hip replacement risk due to, in part, running's association with lower BMI, whereas other exercise increased OA and hip replacement risk.

Effect of body mass index and physical exercise on risk of knee and hip osteoarthritis: longitudinal data from the Norwegian HUNT Study

BackgroundMechanical joint stress imposed by high body mass index (BMI) is associated with increased risk of knee and hip osteoarthritis. This prospective study investigated the independent and joint association of...

Incidence of physician-diagnosed osteoarthritis among active duty United States military service members

To examine the incidence of osteoarthritis and the influence of demographic and occupational factors associated with this condition among active duty US service members between 1999 and 2008. To determine the total number of incident cases of osteoarthritis, the Defense Medical Surveillance System (DMSS) was queried by sex, race, age, branch of military service, and rank using code 715 of the International Classification of Diseases, Ninth Revision, Clinical Modification. Multivariable Poisson regression analysis was used to estimate incidence rates, rate ratios, and 95% confidence intervals (95% CIs) for osteoarthritis per 1,000 person-years. A total of 108,266 incident cases of osteoarthritis were documented in the DMSS within a population that experienced 13,768,885 person-years at risk of disease during the study period. The overall unadjusted incidence rate among all active duty US service members during the study period was 7.86 cases per 1,000 person-years. Significant demographic and occupational risk factors for osteoarthritis included sex, age, race, branch of service, and rank (P<0.001). Women experienced an adjusted incidence rate for osteoarthritis that was nearly 20% higher than that for men (rate ratio 1.19 [95% CI 1.17-1.21]). Service members ages≥40 years experienced an adjusted incidence rate for osteoarthritis that was ∼19 times higher than that for those ages<20 years (rate ratio 18.61 [95% CI 17.57-19.57]). Black service members experienced significantly higher incidence rates of osteoarthritis than those in the white and "other" race categories. Rates of osteoarthritis were significantly higher in military populations than in comparable age groups in the general population.

Development of a population-based microsimulation model of osteoarthritis in Canada

The purpose of the study was to develop a population-based simulation model of osteoarthritis (OA) in Canada that can be used to quantify the future health and economic burden of OA under a range of scenarios for changes in the OA risk factors and treatments. In this article we describe the overall structure of the model, sources of data, derivation of key input parameters for the epidemiological component of the model, and preliminary validation studies. We used the Population Health Model (POHEM) platform to develop a stochastic continuous-time microsimulation model of physician-diagnosed OA. Incidence rates were calibrated to agree with administrative data for the province of British Columbia, Canada. The effect of obesity on OA incidence and the impact of OA on health-related quality of life (HRQL) were modeled using Canadian national surveys. Incidence rates of OA in the model increase approximately linearly with age in both sexes between the ages of 50 and 80 and plateau in the very old. In those aged 50+, the rates are substantially higher in women. At baseline, the prevalence of OA is 11.5%, 13.6% in women and 9.3% in men. The OA hazard ratios for obesity are 2.0 in women and 1.7 in men. The effect of OA diagnosis on HRQL, as measured by the Health Utilities Index Mark 3 (HUI3), is to reduce it by 0.10 in women and 0.14 in men. We describe the development of the first population-based microsimulation model of OA. Strengths of this model include the use of large population databases to derive the key parameters and the application of modern microsimulation technology. Limitations of the model reflect the limitations of administrative and survey data and gaps in the epidemiological and HRQL literature.

Daily Affect Relations in Fibromyalgia Patients Reveal Positive Affective Disturbance

To examine daily positive affective disturbance in the context of negative affect (NA) and pain among patients with fibromyalgia (FM) to determine a) if FM patients experience a deficit in daily positive affect (PA) relative to osteoarthritis (OA) patients; b) if FM patients differ from OA patients in the day-to-day relations of PA and NA; and c) if patients diagnosed with both OA and FM differ from patients with either OA-only or FM-only with respect to major outcomes. A total of 260 women with physician-diagnosed OA (n = 106), FM (n = 53), or OA/FM (n = 101) completed a 30-day electronic diary. Participants were assessed once daily on levels of PA, NA, and pain. Multilevel models indicated that FM patients had less overall PA than OA patients and exhibited a stronger inverse PA-NA relation. Analyses further suggest that the OA/FM group may have been the most impaired of the three included in our study. This group was responsible for a lagged effect of PA on both affects, whereby high PA days resulted in low next-day PA and high next-day NA. FM patients exhibit a PA disturbance compared with OA patients. This disturbance is reflected by an overall deficit in PA and an inability to sustain PA in the face of pain and NA. Patients with both OA and FM may represent a subgroup of FM that is at particular risk for dysregulation of PA.

Ethnicity may be a risk modifier for knee osteoarthritis

Evaluation of: Wright NC, Kershner Riggs G, Lisse JR, Chen Z: Self-reported osteoarthritis, ethnicity, body mass index, and other associated risk factors in postmenopausal women – results from the Women’s Health Initiative. J. Am. Geriatr. Soc. 56(9), 1736–1743 (2008). Participants in the Women’s Health Initiative were examined for risk factors for physician-diagnosed osteoarthritis (OA), including ethnicity. This study compared 82,795 women without OA with 63,600 women with OA, including 85% white, 9.4% African–American, 3.3% Hispanic, 1.9% Asian and 0.5% American Indian women. Age and body mass index were the strongest risk factors for disease. The distribution of risk factors varied between ethnic groups, being lowest in non-Hispanic white women. Stratification according to ethnicity was performed and the data were examined for interaction. The odds of OA in the highest body mass index category were higher in African–American women (odds ratio [OR]: 3.31; 95% confidence interval [CI]: 2.79–3.91) and Am...