Natural history of radiographic hip osteoarthritis: A retrospective cohort study with 11-28 years of followup

Objective

To evaluate the association between radiographic hip osteoarthritis (OA) and future total hip replacement (THR) due to OA or hip fracture.

Methods

We studied a cohort of individuals who had colon radiography from 1980–1997. Minimal joint space (MJS) was measured and each hip was graded for radiographic OA according to the Kellgren/Lawrence scale. Subjects were followed until the end of 2008. A Cox proportional hazards model, adjusted for age and sex, was used to evaluate factors associated with THR and hip fracture.

Results

A total of 2,953 hips were studied (57% women). The cumulative incidence of THR was 2.5% and the cumulative incidence of hip fracture was 2.6%. For hips with radiographic hip OA (MJS of 2.5 mm or less), the cumulative incidence of THR was 16.9% and the hazard ratio (HR) for THR was 13.2 (95% confidence interval [95% CI] 8.1–21). Using Kellgren/Lawrence grading, the HR for THR was 12.9 (95% CI 7.9–21) for hips with radiographic OA compared to those without. The HR for all types of hip fracture for hips with radiographic OA (MJS of 2.5 mm or less) was 0.47 (95% CI 0.15–1.5), for intracapsular fractures was 0.29 (95% CI 0.04–2.1), and for extracapsular fractures was 0.67 (95% CI 0.16–2.8).

Conclusion

The risk of THR due to OA is substantially increased in patients with radiographic hip OA, regardless of symptoms, and increases with decreasing MJS. However, 11–28 years after having had radiographic hip OA, more than 4 of 5 of those having radiographic signs of hip OA had not had a THR for OA.     

Association of nitrate use with risk of new radiographic features of hip osteoarthritis in elderly white women: the study of osteoporotic fractures

OBJECTIVE: To examine the association between nitrate medication use and the development of new radiographic findings of hip osteoarthritis (OA) in elderly women. METHODS: Pelvic radiographs were obtained at baseline and a mean of 8.3 years later in 5,987 women, age > or =65 years at the baseline examination of the Study of Osteoporotic Fractures. Atlas-standardized individual radiographic features (IRFs) of OA were assessed and minimal joint space was measured on paired films. New radiographic findings of hip OA were defined as the development in hips free of these findings at baseline: 1) joint space narrowing (JSN), which consisted of either a MJS < or =1.5 mm or an IRF score indicating lateral JSN > or =2 or medial JSN > or =3; 2) an IRF score for osteophytes of > or =2 in any location; or 3) a summary grade of 2 or more (at least 2 IRFs present). Nitrate use was recorded by interview at years 6 and 8. Logistic and linear regression analyses were performed to determine the association of nitrate use with new radiographic findings of hip OA, adjusting for age, weight, height, bone mineral density, and estrogen. RESULTS: Compared with no reported use of nitrates, we found significant associations between use of nitrates at 1 clinic visit and new JSN (odds ratio [OR] 1.94, 95% confidence interval [95% CI] 1.18-3.17, P = 0.009), new osteophyte formation (OR 1.70, 95% CI 1.03-2.88, P = 0.04), and any new radiographic finding of hip OA or total hip arthroplasty for OA (OR 1.71, 95% CI 1.16-2.52, P = 0.007). Any nitrate use was associated with an increased risk of developing summary grade 3 or greater hip OA (OR 1.84, 95% CI 1.03-3.31, P = 0.041), but not with any other incident findings of OA. CONCLUSION: Older women using nitrates may have an increased risk of developing new radiographic findings of hip OA.     

Bone mineral density varies as a function of the rate of joint space narrowing in the hip

OBJECTIVE: To determine whether patients with a rapid rate of joint space narrowing (JSN) in the hip have higher initial bone mineral density (BMD) in the proximal femur and/or lumbar spine than corresponding patients with a slow rate of JSN. METHODS: Twenty-eight patients undergoing unilateral total hip replacement (THR) for osteoarthritis (OA), but whose contralateral hips were asymptomatic and had minimal or no radiographic OA, were evaluated. The contralateral proximal femur (i.e., non-operated hip) and lumbar spine were scanned by dual energy x-ray absorptiometry at baseline (prior to THR) and at 2 years. The rate of JSN was determined by serial longitudinal quantification of the joint spaces over the 2 year period following THR from conventional radiographs, and the patients were divided into a group with a slow rate of JSN (< or = 0.2 mm/yr, n = 20) and a group with a rapid rate of JSN (> 0.2 mm/yr, n = 8). RESULTS: The baseline BMD z and t scores at the femoral neck, Ward's triangle, and lumbar spine of the patients with subsequent rapid rates of JSN were significantly higher than those of patients with slower rates (p < 0.05). There was no difference between the rapid and slow narrowers at the greater trochanter (p > 0.2). Age, sex, weight, height, body mass index, Kellgren- Lawrence scores, and initial joint space width were not significantly different between the 2 groups. CONCLUSION: Patients with a rapid rate of JSN of the asymptomatic hip after unilateral THR are characterized by elevated local and remote BMD. The local elevation in BMD implies that increased local bone density may contribute to or serve as a marker for increased risk of development of OA (assuming that JSN can be used as a predictive marker). The presence of elevated BMD in the spine suggests that there are systemic as well as local aspects of OA pathogenesis, at least in patients with one THR and rapid JSN in the contralateral hip.     

Defining incident radiographic hip osteoarthritis for epidemiologic studies in women

Objective

To evaluate definitions of radiographic hip osteoarthritis (RHOA) for use in longitudinal epidemiologic studies of disease incidence in women.

Methods

We studied 5,839 women from the Study of Osteoporotic Fractures who had had serial pelvic radiographs obtained (mean of 8.3 years apart) and who were followed up (mean followup 7.1 years from the time of the second radiograph) for evaluation of clinical outcomes. Definitions of RHOA were assessed for construct validity (association with symptoms and signs at the time of the second radiograph) and predictive validity (association with total hip replacement [THR] and signs and symptoms a mean of 7.1 years later). Odds ratios (ORs) and 95% confidence intervals were calculated to assess the strength of association using logistic regression.

Results

The cumulative incidence of RHOA ranged from 2.2% to 11.7%. All definitions displayed significant construct validity; the most consistent was found for composite definitions that required the concurrent presence of 2 or more individual radiographic features and definitions based on stringent criteria for joint space narrowing. All definitions except minimum joint space ≤2.5 mm displayed consistent predictive validity. Composite definitions had the strongest associations with THR (OR 10.5–18.5) and hip pain (OR 2.6–2.9). The hips identified as having OA by each definition varied, with especially small overlap between findings using definitions based on osteophytes and those using definitions based on joint space narrowing alone.

Conclusion

Most definitions of incident RHOA display good construct and predictive validity. Composite definitions have the best overall performance, and definitions requiring the presence of both osteophytes (in particular, femoral osteophytes) and joint space narrowing would be recommended for most epidemiologic and genetic studies.

     

Effects of doxycycline on progression of osteoarthritis: results of a randomized, placebo-controlled, double-blind trial

OBJECTIVE: To confirm preclinical data suggesting that doxycycline can slow the progression of osteoarthritis (OA). The primary outcome measure was joint space narrowing (JSN) in the medial tibiofemoral compartment. METHODS: In this placebo-controlled trial, obese women (n = 431) ages 45-64 years with unilateral radiographic knee OA were randomly assigned to receive 30 months of treatment with 100 mg doxycycline or placebo twice a day. Tibiofemoral JSN was measured manually in fluoroscopically standardized radiographic examinations performed at baseline, 16 months, and 30 months. Severity of joint pain was recorded at 6-month intervals. RESULTS: Seventy-one percent of all randomized subjects completed the trial. Radiographs were obtained from 85% of all randomized subjects at 30 months. Adherence to the dosing regimen was 91.8% among subjects who completed the study per protocol. After 16 months of treatment, the mean +/- SD loss of joint space width in the index knee in the doxycycline group was 40% less than that in the placebo group (0.15 +/- 0.42 mm versus 0.24 +/- 0.54 mm); after 30 months, it was 33% less (0.30 +/- 0.60 mm versus 0.45 +/- 0.70 mm). Doxycycline did not reduce the mean severity of joint pain, although pain scores in both treatment groups were low at baseline and remained low throughout the trial, suggesting the presence of a floor effect. However, the frequency of followup visits at which the subject reported a > or = 20% increase in pain in the index knee, relative to the previous visit, was reduced among those receiving doxycycline. In contrast, doxycycline did not have an effect on either JSN or pain in the contralateral knee. In both treatment groups, subjects who reported a > or = 20% increase in knee pain at the majority of their followup visits had more rapid JSN than those whose pain did not increase. CONCLUSION: Doxycycline slowed the rate of JSN in knees with established OA. Its lack of effect on JSN in the contralateral knee suggests that pathogenetic mechanisms in that joint were different from those in the index knee.     

Association of higher levels of serum cartilage oligomeric matrix protein and N-telopeptide crosslinks with the development of radiographic hip osteoarthritis in elderly women

OBJECTIVE: To examine the association of baseline concentrations of serum cartilage oligomeric matrix protein (COMP) and serum N-telopeptide crosslinks (NTX) with the development and progression of radiographic hip osteoarthritis (RHOA) in elderly women. METHODS: Pelvic radiographs were obtained a mean of 8.3 years apart from white women > or =65 years of age enrolled in the Study of Osteoporotic Fractures. Random sampling from a cohort of 5,928 subjects was performed, with subjects ( approximately 200 per group) assigned to nested case-control studies, one focusing on RHOA incidence and the other on RHOA progression. Baseline serum levels of COMP and NTX were measured by enzyme-linked immunosorbent assay in duplicate. Odds ratios (ORs) and 95% confidence intervals (95% CIs), indicating the likelihood of baseline serum COMP and NTX levels to be predictive of the development or progression of RHOA, were calculated using logistic regression analysis, with adjustment for potential covariates. RESULTS: At baseline, incident cases of RHOA were associated with higher serum levels of COMP and NTX (P < 0.05 for each) compared with the no RHOA control group. Higher baseline serum COMP and NTX levels were associated with an increased risk of incident RHOA compared with the no RHOA group, with an adjusted OR of 1.31 per SD increase in COMP (95% CI 1.02-1.68) and adjusted OR of 1.38 per SD increase in NTX (95% CI 1.07-1.79). In this community-based cohort, progression of RHOA was modest. However, there was a trend toward increased risk of RHOA progression with higher baseline COMP and NTX levels. CONCLUSION: These data suggest that serum levels of COMP and NTX are modest risk markers for the development of RHOA in a community-based cohort of elderly white women.     

Acetabular dysplasia predicts incident osteoarthritis of the hip: the Rotterdam study

OBJECTIVE: To investigate the association between acetabular dysplasia and the incidence of radiographic osteoarthritis (OA) of the hip in a population-based sample of elderly subjects. METHODS: Radiographs of the hip at baseline and at followup (mean followup time 6.6 years) were evaluated in 835 men and women (age >or=55 years) from the Rotterdam Study. Subjects with a baseline Kellgren/Lawrence grade of 0 or 1 in both hips were included in the study. Incident radiographic OA of the hip was defined as a decrease of joint space width of the hip (>or=1.0 mm) at followup. Acetabular dysplasia was assessed using the center-edge angle and the acetabular depth. The association between acetabular dysplasia and incident radiographic hip OA was assessed by calculating odds ratios using multivariate regression analysis. RESULTS: In this study population with a mean +/- SD age of 65.6 +/- 6.5 years, 9.3% developed incident radiographic hip OA. Subjects with acetabular dysplasia (center-edge angle <25 degrees ) had a 4.3-fold increased risk for incident radiographic OA of the hip (95% confidence interval 2.2-8.7) compared with subjects without acetabular dysplasia. These associations were independent of known determinants of hip OA such as age, sex, and body mass index (BMI), but tended to be enhanced by female sex, heavy mechanical load, and low BMI. CONCLUSION: In a study population age >or=55 years, acetabular dysplasia is still a strong independent determinant of incident radiographic hip OA.     

Wnt signaling antagonists are potential prognostic biomarkers for the progression of radiographic hip osteoarthritis in elderly Caucasian women

OBJECTIVE: To determine whether serum levels of 2 Wnt signaling antagonists, Frizzled-related protein (FRP) and Dkk-1, are associated with the development and progression of radiographic hip osteoarthritis (RHOA). METHODS: Pelvic radiographs were obtained a mean of 8.3 years apart in 5,928 Caucasian women >or=65 years of age who were enrolled in the Study of Osteoporotic Fractures. Random sampling of this cohort was performed, with approximately 180 subjects per group assigned to 2 nested case-control studies on RHOA incidence and progression. Baseline serum levels of FRP and Dkk-1 were measured by capture enzyme-linked immunosorbent assay. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated using logistic regression analyses with adjustment for potential covariates. RESULTS: There were no differences in serum levels of FRP and Dkk-1 between case subjects with incidence or progression of RHOA and their respective control subjects. There was a trend for higher baseline serum levels of FRP to be associated with a reduced risk of incident RHOA (age-adjusted OR 0.59 [95% CI 0.32-1.09], P = 0.09 for women in the highest quartile versus women in the lowest quartile). There was no association of serum levels of FRP with progression of RHOA. Serum levels of Dkk-1 did not correlate with incident RHOA. However, higher serum levels of Dkk-1 were associated with diminished risk of RHOA progression (age-adjusted OR 0.43 [95% CI 0.23-0.79], P = 0.007 for women in the highest quartile compared with women in the lowest quartile). CONCLUSION: Elevated circulating levels of Dkk-1 appeared to be associated with reduced progression of RHOA in elderly women, whereas the highest quartile of serum FRP levels tended to be associated with a modest reduction in risk of incident RHOA.     

Radiographic change is common in new presenters in primary care with hip pain. PCR Hip Study Group

OBJECTIVE: To determine the prevalence of radiographic osteoarthritis in subjects with hip pain newly presenting to primary care. METHODS: The study was cross-sectional in design, set in 35 general practices across the UK. It included 195 men and women aged 40 yr and over (median 63 yr) presenting with a new episode of hip pain. Hip radiographs were scored for minimum joint space (MJS) and overall-Croft's modification of the Kellgren and Lawrence (Croft)-grade of osteoarthritis. RESULTS: In all, definite evidence of radiographic change in the painful joint was common: Croft grade > or =2 in 44%, > or =3 in 34%. MJS of 2.5 mm or less was seen in 30% of whom half were below 1.5 mm. There were no significant gender differences in radiographic severity. CONCLUSIONS: Radiographic change is common in patients newly presenting with hip pain and many already have advanced disease.     

Procollagen II C propeptide level in the synovial fluid as a predictor of radiographic progression in early knee osteoarthritis

OBJECTIVE: To investigate the prognostic value of procollagen type II carboxy-terminal propeptide (PIICP) level in synovial fluid in relation to early tibiofemoral joint osteoarthritis (OA). METHODS: Data were collected on 172 women (age 40 to 59 years) who had knee pain and tibiofemoral joint OA in the early stage. Standing semiflexed knee radiographs were obtained by fluoroscopy at baseline and at four year follow up and a computerised, magnification corrected measurement system was applied to measurement of minimal joint space width in the tibiofemoral compartment. Synovial fluid sampling was performed at baseline and at the four year follow up. Levels of PIICP in the synovial fluid were measured by enzyme immunoassay. The outcome measures were assessed by radiographic joint space narrowing (JSN) in the tibiofemoral joints over four years. Multiple linear regression analyses were used to examine the relation between radiographic JSN and synovial fluid level of PIICP. RESULTS: The number of women available at both baseline and at four year follow up was 110. The average of radiographic JSN over four years was 0.53 mm (range 0.00-2.01). Body mass index showed a slightly positive association with baseline PIICP level. In multiple linear regression analyses adjusted for age and body mass index, radiographic JSN over four years had a direct positive correlation with baseline PIICP level (r=0.395; 95% confidence interval (95% CI) 0.231 to 0.529; p<0.001). CONCLUSION: In a four year prospective study of women, quantification of synovial fluid PIICP was able to predict subsequent radiographic progression in early tibiofemoral joint OA.     

Characterization of individual radiographic features of hip osteoarthritis in African American and White Women and Men: The Johnston County Osteoarthritis Project

Objective

To describe differences in radiographic features of hip osteoarthritis (OA) between African American and white men and women.

Methods

We conducted a cross‐sectional analysis of radiographic hip OA using baseline data from the Johnston County Osteoarthritis Project, using Kellgren/Lawrence (K/L) grade, and the presence, location, and severity of 4 individual radiographic features (joint space narrowing [JSN], subchondral cysts, sclerosis, and osteophytes). Sex‐specific logistic regression was used to evaluate associations between race and individual radiographic features, adjusting for age, body mass index, education, and prior hip injury. Robust variance estimators via generalized estimating equations were used to account for correlation between hips from the same individual.

Results

The sample (n = 2,739) comprised 57% women and 31% African American participants. Among women, African Americans and whites had a similar prevalence of hip OA, defined as K/L grade ≥2 (23% versus 22%), but African American women were significantly more likely to have superior or medial JSN, moderate or severe axial JSN, medial or lateral osteophytes, and subchondral cysts. Among men, 21% of African Americans and 17% of whites had hip OA; African American men were more likely to have superior or medial JSN and lateral osteophytes, but were less likely to have axial JSN.

Conclusion

Individual radiographic features and patterns of hip OA differed by race among women and men, suggesting the possibility of anatomic and/or developmental variation in the hip joint. African Americans have an increased frequency of features that have been predictive of hip replacement in other populations, a finding worthy of further study.     

Acetabular dysplasia and the risk of developing hip osteoarthritis at 2,5,8, and 10 years follow-up in a prospective nationwide cohort study (CHECK).

ObjectiveTo assess the relationship between acetabular dysplasia (AD) and the risk of incident and end-stage radiographic hip osteoarthritis (RHOA) over 2,5,8 and 10 years.DesignIndividuals (n = 1002) aged between 45 and 65 from the prospective Cohort Hip and Cohort Knee (CHECK) were studied. Anteroposterior pelvic radiographs were obtained at baseline and 2,5,8, and 10-years follow-up. False profile radiographs were obtained at baseline. AD was defined as a lateral center edge angle, an anterior center edge angle, or both <25° at baseline. The risk of developing RHOA was determined at each follow-up moment. Incident RHOA was defined by Kellgren & Lawrence (KL) grade ≥2 or total hip replacement (THR), end-stage RHOA by a KL grade ≥3 or THR. Associations were expressed in odds ratios (OR) using logistic regression with generalized estimating equations.ResultsAD was associated with the development of incident RHOA at 2 years follow-up (OR 2.46, 95% CI 1.00–6.04), 5 years follow-up (OR 2.28, 95% CI 1.20–4.31), and 8 years follow-up (OR 1.86, 95%CI 1.22–2.83). AD was only associated with end-stage RHOA at 5 years follow-up (OR 3.75, 95% CI 1.02–13.77). No statistically significant associations were observed between AD and RHOA at 10-years follow-up.ConclusionBaseline AD in individuals between 45 and 65 years is associated with an increased risk of developing RHOA within 2- and 5 years. However, this association seems to weaken after 8 years and disappears after 10 years.     

Changes in proximal femoral mineral geometry precede the onset of radiographic hip osteoarthritis: The study of osteoporotic fractures

Objective

Radiographic hip osteoarthritis (RHOA) is associated with increased hip areal bone mineral density (aBMD). This study was undertaken to examine whether femoral geometry is associated with RHOA independent of aBMD.

Methods

Participants in the Study of Osteoporotic Fractures in whom pelvic radiographs had been obtained at visits 1 and 5 (mean 8.3 years apart) and hip dual x‐ray absorptiometry (DXA) had been performed (2 years after baseline) were included. Prevalent and incident RHOA phenotypes were defined as composite (osteophytes and joint space narrowing [JSN]), atrophic (JSN without osteophytes), or osteophytic (femoral osteophytes without JSN). Analogous definitions of progression were based on minimum joint space and total osteophyte score. Hip DXA scans were assessed using the Hip Structural Analysis program to derive geometric measures, including femoral neck length, width, and centroid position. Relative risks and 95% confidence intervals for prevalent, incident, and progressive RHOA per SD increase in geometric measure were estimated in a hip‐based analysis using multinomial logistic regression with adjustment for age, body mass index, knee height, and total hip aBMD.

Results

In 5,245 women (mean age 72.6 years), a wider femoral neck with a more medial centroid position was associated with prevalent and incident osteophytic and composite RHOA phenotypes (P < 0.05). Increased neck width and centroid position were associated with osteophyte progression (both P < 0.05). No significant geometric associations with atrophic RHOA were found.

Conclusion

Differences in proximal femoral bone geometry and spatial distribution of bone mass occur early in hip OA and predict prevalent, incident, and progressive osteophytic and composite phenotypes, but not the atrophic phenotype. These bone differences may reflect responses to loading occurring early in the natural history of RHOA.

     

Effects of doxycycline on progression of osteoarthritis: Results of a randomized,placebo‐controlled,double‐blind trial

Objective

To confirm preclinical data suggesting that doxycycline can slow the progression of osteoarthritis (OA). The primary outcome measure was joint space narrowing (JSN) in the medial tibiofemoral compartment.

Methods

In this placebo‐controlled trial, obese women (n = 431) ages 45–64 years with unilateral radiographic knee OA were randomly assigned to receive 30 months of treatment with 100 mg doxycycline or placebo twice a day. Tibiofemoral JSN was measured manually in fluoroscopically standardized radiographic examinations performed at baseline, 16 months, and 30 months. Severity of joint pain was recorded at 6‐month intervals.

Results

Seventy‐one percent of all randomized subjects completed the trial. Radiographs were obtained from 85% of all randomized subjects at 30 months. Adherence to the dosing regimen was 91.8% among subjects who completed the study per protocol. After 16 months of treatment, the mean ± SD loss of joint space width in the index knee in the doxycycline group was 40% less than that in the placebo group (0.15 ± 0.42 mm versus 0.24 ± 0.54 mm); after 30 months, it was 33% less (0.30 ± 0.60 mm versus 0.45 ± 0.70 mm). Doxycycline did not reduce the mean severity of joint pain, although pain scores in both treatment groups were low at baseline and remained low throughout the trial, suggesting the presence of a floor effect. However, the frequency of followup visits at which the subject reported a ≥20% increase in pain in the index knee, relative to the previous visit, was reduced among those receiving doxycycline. In contrast, doxycycline did not have an effect on either JSN or pain in the contralateral knee. In both treatment groups, subjects who reported a ≥20% increase in knee pain at the majority of their followup visits had more rapid JSN than those whose pain did not increase.

Conclusion

Doxycycline slowed the rate of JSN in knees with established OA. Its lack of effect on JSN in the contralateral knee suggests that pathogenetic mechanisms in that joint were different from those in the index knee.

     

Influence of familial factors on radiologic disease progression over two years in siblings with osteoarthritis at multiple sites: a prospective longitudinal cohort study

OBJECTIVE: The contribution of genetics to osteoarthritis (OA) progression is not known. To gain more insight into whether familial factors play a role in disease progression of OA, we analyzed familial aggregation of radiologic OA progression in a study of sibling pairs (the Genetics, Arthrosis, and Progression [GARP] study). METHODS: A total of 105 white probands and their 105 siblings with OA at multiple joint sites were included in a prospective cohort study. Radiologic progression of OA was defined as a 1-point score increase in total scores for severity of joint space narrowing (JSN) or osteophytes on standardized radiographs of the hands, knees, and hips obtained at baseline and after 2 years. Odds ratios were calculated for siblings and probands sharing radiologic disease progression. RESULTS: A total of 100 probands and 93 siblings were followed for 2 years (median age 60 years, 80% women). In 92 sibling pairs both the proband and sibling had complete radiographic followup. Radiologic progression of JSN and osteophytes was present in 47% and 42% of the probands and 34% and 37% of the siblings, respectively. The odds ratios (95% confidence intervals), adjusted for age, sex, and body mass index, of a sibling having radiologic progression if the proband had progression were 3.0 (1.2-7.8) for JSN progression and 1.5 (0.6-3.6) for osteophyte progression. A dose-response relationship was found between the amount of increase in JSN total scores among probands and the progression of JSN in siblings. CONCLUSION: Familial factors played a role in the radiologic progression of JSN over 2 years in patients with OA at multiple sites.     

Investigation of the association of weight loss with radiographic hip osteoarthritis in older community-dwelling female adults

Objective

Most guidelines recommending weight loss for hip osteoarthritis are based on research on knee osteoarthritis. Prior studies found no association between weight loss and hip osteoarthritis, but no previous studies have targeted older adults. Therefore, we aimed to determine whether there is any clear benefit of weight loss for radiographic hip osteoarthritis in older adults because weight loss is associated with health risks in older adults.

Methods

We used data from white female participants aged ≥65 years from the Study of Osteoporotic Fractures. Our exposure of interest was weight change from baseline to follow-up at 8 years. Our outcomes were the development of radiographic hip osteoarthritis (RHOA) and the progression of RHOA over 8 years. Generalized estimating equations (clustering of 2 hips per participant) were used to investigate the association between exposure and outcomes adjusted for major covariates.

Results

There was a total of 11,018 hips from 5509 participants. There was no associated benefit of weight loss for either of our outcomes. The odds ratios (95% confidence intervals) for the development and progression of RHOA were 0.99 (0.92–1.07) and 0.97 (0.86–1.09) for each 5% weight loss, respectively. The results were consistent in sensitivity analyses where participants were limited to those who reported trying to lose weight and who also had a body mass index in the overweight or obese range.

Conclusion

Our findings suggest no associated benefit of weight loss in older female adults in the structure of the hip joint as assessed by radiography.     

Association of higher levels of serum cartilage oligomeric matrix protein and N‐telopeptide crosslinks with the development of radiographic hip osteoarthritis in elderly women

Objective

To examine the association of baseline concentrations of serum cartilage oligomeric matrix protein (COMP) and serum N‐telopeptide crosslinks (NTX) with the development and progression of radiographic hip osteoarthritis (RHOA) in elderly women.

Methods

Pelvic radiographs were obtained a mean of 8.3 years apart from white women ≥65 years of age enrolled in the Study of Osteoporotic Fractures. Random sampling from a cohort of 5,928 subjects was performed, with subjects (∼200 per group) assigned to nested case–control studies, one focusing on RHOA incidence and the other on RHOA progression. Baseline serum levels of COMP and NTX were measured by enzyme‐linked immunosorbent assay in duplicate. Odds ratios (ORs) and 95% confidence intervals (95% CIs), indicating the likelihood of baseline serum COMP and NTX levels to be predictive of the development or progression of RHOA, were calculated using logistic regression analysis, with adjustment for potential covariates.

Results

At baseline, incident cases of RHOA were associated with higher serum levels of COMP and NTX (P < 0.05 for each) compared with the no RHOA control group. Higher baseline serum COMP and NTX levels were associated with an increased risk of incident RHOA compared with the no RHOA group, with an adjusted OR of 1.31 per SD increase in COMP (95% CI 1.02–1.68) and adjusted OR of 1.38 per SD increase in NTX (95% CI 1.07–1.79). In this community‐based cohort, progression of RHOA was modest. However, there was a trend toward increased risk of RHOA progression with higher baseline COMP and NTX levels.

Conclusion

These data suggest that serum levels of COMP and NTX are modest risk markers for the development of RHOA in a community‐based cohort of elderly white women.

     

Prognosis of hip pain in general practice: a prospective followup study

OBJECTIVE: Hip pain in the elderly is the main feature of osteoarthritis of the hip. In this prospective followup study, we wanted to determine which patients with hip pain show disease progression, and what the incidence of total hip replacement (THR) is in this group of patients after 3 and 6 years of followup. METHODS: Within general practices in the area of Rotterdam (The Netherlands), persons age > or = 50 years with incident hip pain were included. After 3 and 6 years, progression of hip pain was assessed. RESULTS: A total of 224 patients were included. After 3 years disease progressed in 29 (15%) patients and 23 (12%) received a THR. After 6 years disease progressed in 45 (28%) patients and 36 (22%) received a THR. The prognostic variables for a THR after 3 and 6 years related to history taking were age > or = 60 years, morning stiffness, and pain in the groin/medial thigh; variables related to physical examination were decreased extension/adduction, painful internal rotation, and a body mass index < or = 30 kg/m(2); and the variable related to radiologic findings was a Kellgren/Lawrence grade of 2 or higher. CONCLUSION: In this study population, approximately 12% of patients presenting with hip pain to their general practitioner will undergo a THR within 3 years, and approximately 22% after 6 years. Using the variables obtained from history taking, physical examination, and radiologic findings enables better identification of persons at high risk for a THR.     

Early identification of radiographic osteoarthritis of the hip using an active shape model to quantify changes in bone morphometric features: can hip shape tell us anything about the progression of osteoarthritis?

OBJECTIVE: Few methods exist to measure the progression of osteoarthritis (OA) or to identify people at high risk of developing OA. Striking radiographic changes include deformation of the femoral head and osteophyte growth, which are usually measured semiquantitatively following visual assessment. In this study, an active shape model (ASM) of the proximal femur was used to determine whether morphologic changes to the bone could be quantified and used as a marker of hip OA. METHODS: One hundred ten subjects who had no signs of radiographic hip OA at baseline (Kellgren/Lawrence [K/L] scores 0-1) were selected from the Rotterdam Study cohort of subjects ages > or = 55 years. To measure the progression of OA, subjects were followed up with radiographic assessment after 6 years. At the 6-year followup, 55 subjects had established OA (K/L score 3), and in 12 of these OA subjects, the progression of the disease required a total hip replacement (THR). Age- and sex-matched control subjects had a K/L score of 0 at followup. Using the ASM, subjects were assessed for shape changes in the femoral head and neck before, during, and after the development of radiographic OA. Scores of shape variance, or mode scores, were assigned for 10 modes of variation in each subject, and differences in mode scores were determined. RESULTS: During followup, significant changes in shape of the proximal femur occurred within the OA group from baseline to followup (P < 0.0001 for mode 1 and P = 0.002 for mode 6) but not within the control group. At baseline (all subjects having K/L scores 0-1), there were significant differences in mode 6 between the OA group and the control group (P = 0.020), and in modes 3 and 6 between the OA subjects who underwent THR and the remaining OA subjects (P = 0.012 and P = 0.019, respectively). CONCLUSION: Compared with traditional scoring methods, the ASM can be used more precisely to quantify the deforming effect of OA on the proximal femur and to identify, at an earlier stage of disease, those subjects at highest risk of developing radiographic OA or needing a THR. The ASM may therefore be useful as an imaging biomarker in the assessment of patients with hip OA.