M C Nevitt

University of San Francisco, San Francisco, California, United States

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Publications (352)2243.24 Total impact

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    ABSTRACT: To determine whether women experience greater knee pain severity than men at equivalent levels of radiographic knee osteoarthritis (OA).
    Osteoarthritis and cartilage / OARS, Osteoarthritis Research Society. 07/2014;
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    ABSTRACT: Little is known about early knee osteoarthritis (OA). The significance of lesions on magnetic resonance imaging (MRI) in older persons without radiographic OA is unclear. Our objectives were to determine the extent of tissue pathology by MRI and evaluate its significance by testing the following hypotheses: cartilage damage, bone marrow lesions, and meniscal damage are associated with prevalent frequent knee symptoms and incident persistent symptoms; bone marrow lesions and meniscal damage are associated with incident tibiofemoral (TF) cartilage damage; and bone marrow lesions are associated with incident patellofemoral (PF) cartilage damage.
    Arthritis & rheumatology (Hoboken, N.J.). 07/2014; 66(7):1811-9.
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    ABSTRACT: To identify genetic associations with hip osteoarthritis (HOA), we performed a meta-analysis of genome-wide association studies (GWAS) of HOA.
    Annals of the rheumatic diseases. 06/2014;
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    ABSTRACT: Background: Physical activity is recommended to mitigate functional limitations associated with knee osteoarthritis (OA). However, it is unclear whether walking on its own protects against the development of functional limitation. Methods: Walking over 7 days was objectively measured as steps/day within a cohort of people with or at risk of knee OA from the Multicenter Osteoarthritis Study. Incident functional limitation over two years was defined by performance-based (gait speed ≤ 1.0 m/s) and self-report (WOMAC physical function ≥ 28/68) measures. We evaluated the association of steps/day at baseline with developing functional limitation two years later by calculating risk ratios adjusted for potential confounders. The number of steps/day that best distinguished risk for developing functional limitation was estimated from the maximum distance from chance on Receiver Operator Characteristic curves. Results: Among 1788 participants (mean age 67, mean BMI 31 kg/m(2) , female 60%), each additional 1000 steps/day was associated with a 16% and 18% reduction in incident functional limitation by performance-based and self-report measures, respectively. Walking < 6000 and < 5900 steps/day were the best thresholds to distinguish incident functional limitation by performance-based (67.3%/71.8% [sensitivity/specificity]) and self-report (58.7%/68.9%) measures, respectively. Conclusions: More walking was associated with less risk of functional limitation over two years. Walking ≥ 6000 steps/day provides a preliminary estimate of the level of walking activity to protect against developing functional limitation in people with or at risk of knee OA. © 2014 American College of Rheumatology.
    Arthritis care & research. 06/2014;
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    ABSTRACT: Background The ability to walk for short and prolonged periods of time is often measured with separate walking tests. It is unclear whether decline in the two-minute walk coincides with decline in a shorter 20-meter walk among older adults.Objective To describe patterns of change in the 20-meter walk and two-minute walk over 8 years among a large cohort of older adults. Should change be similar between tests of walking ability, separate re-testing of prolonged walking may need to be reconsidered.DesignLongitudinal Observational CohortMethods Data were from 1,893 well-functioning older adults (≥ 70 years). The 20-meter walk and two-minute walk were repeatedly measured over 8 years to measure change in short- and prolonged-walking, respectively. Change was examined using a dual group-based trajectory model (dual model) and agreement between walking trajectories was quantified with a Weighted Kappa statistic.ResultsThree trajectory groups for the 20-meter walk and two-minute walk were identified. Over 86% of subjects were in similar trajectory groups for both tests from the dual model. There was high chance corrected agreement (Kappa = 0.84, 95%CI [0.81, 0.86]) between 20-meter walk and two-minute walk trajectory groups.LimitationsOne-third of the original Health ABC cohort was excluded from analysis due to missing clinic visits followed by being excluded for health reasons for performing the two-minute walk, limiting generalizability to healthy older adults.Conclusions Patterns of change in the two-minute walk are similar to the 20-meter walk. Thus, separate re-testing of the two-minute walk may need to be reconsidered to gauge change in prolonged walking.
    Physical Therapy 05/2014; · 2.78 Impact Factor
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    ABSTRACT: PurposeTo assess whether changes in knee cartilage MR-based T2 relaxation times are associated with weight loss in individuals with risk factors for knee osteoarthritis (OA) compared with controls with stable weight.Materials and Methods One hundred twenty-seven individuals with risk factors for knee OA were studied: 62 subjects had a body mass index (BMI) decrease≥10% over 48 months and 65 controls had a BMI change <3%. Cartilage segmentation from five knee compartments at baseline and 48-month follow-up was performed, and T2 maps were generated. The association of change in T2 values over 48 months in the weight-loss group versus the control group was assessed using multiple linear regression models.ResultsWeight loss was associated with significantly smaller increases in cartilage T2 in the medial femoral condyle (P = 0.035) and overall medial compartment (P = 0.006) compared with the controls. In a subgroup analysis comparing weight-loss subjects who were obese (BMI≥30 kg/m2) and overweight (BMI 25–30 kg/m2) at baseline, obesity was associated with smaller increases in cartilage T2 values in the medial femoral condyle (P = 0.022), lateral femoral condyle (P = 0.015), patella (P = 0.002), and globally across all compartments (P = 0.002).ConclusionA decrease in BMI of ≥ 10% was associated with a slower progression of T2 values in individuals with risk factors for OA, suggesting a beneficial impact of weight loss on cartilage matrix degeneration. J. Magn. Reson. Imaging 2014. © 2014 Wiley Periodicals, Inc.
    Journal of Magnetic Resonance Imaging 04/2014; · 2.57 Impact Factor
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    ABSTRACT: To evaluate whether T2 relaxation time measurements obtained at 3 T MRI predict the onset of radiographic knee osteoarthritis (OA). We performed a nested case-control study of incident radiographic knee OA in the Osteoarthritis Initiative cohort. Cases were 50 knees with baseline Kellgren-Lawrence (KL) grade of 0 that developed KL grade of 2 or more over a 4-year period. Controls were 80 knees with KL grade of 0 after 4 years of follow-up. Baseline T2 relaxation time measurements and laminar analysis of T2 in deep and superficial layers were performed in all knee compartments. The association of T2 values with incident OA was assessed with logistic regression and differences in T2 values by case-control status with linear regression, adjusting for age, sex, body mass index (BMI) and other covariates. Baseline T2 values in all compartments except the medial tibia were significantly higher in knees that developed OA compared with controls and were particularly elevated in the superficial cartilage layers in all compartments. There was an increased likelihood of incident knee OA associated with higher baseline T2 values, particularly in the patella, adjusted OR per 1 SD increase in T2 (3.37 (95% CI 1.72 to 6.62)), but also in the medial femur (1.90 (1.07 to 3.39)), lateral femur (2.17 (1.11 to 4.25)) and lateral tibia (2.23 (1.16 to 4.31)). These findings suggest that T2 values assessed when radiographic changes are not yet apparent may be useful in predicting the development of radiological tibiofemoral OA.
    Annals of the rheumatic diseases 03/2014; · 8.11 Impact Factor
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    ABSTRACT: Purpose To describe a scoring system for quantification of cartilage lesions (Cartilage Lesion Score [CaLS]), to determine its reproducibility, to examine the association of CaLS-detected longitudinal change with known risk factors for osteoarthritis (OA) progression by comparing a group of subjects with OA risk factors with a group of subjects without OA risk factors, and to compare the CaLS system with the established semiquantitative Whole-Organ Magnetic Resonance Imaging Score (WORMS) and Boston-Leeds Osteoarthritis Knee Score (BLOKS) systems in terms of detection of cartilage defect progression. Materials and Methods All subjects provided written informed consent, and the local institutional review board approved this HIPAA-compliant study. Fifty-two subjects with and 25 subjects without risk factors for knee OA were randomly selected from the Osteoarthritis Initiative. Inclusion criteria were age of 45-60 years, body mass index of 19-27 kg/m(2), and no knee pain or OA on radiographs at baseline. Baseline and 24-month follow-up right knee 3-T magnetic resonance images were analyzed with WORMS, BLOKS, and CaLS systems. Progression of cartilage lesions with each scoring system was compared by using multilevel mixed-effects linear-regression models. κ values were calculated to determine reliability. Results Intraclass coefficient values for inter- and intraobserver reliability of the CaLS system were 0.86 and 0.91, respectively. Interobserver κ value range for individual features was 0.81-0.94. The CaLS system enabled significantly higher detection of cartilage lesion progression than did WORMS or BLOKS systems (P < .001); 51.8% (56 of 108), 17.6% (19 of 108), and 13.0% (14 of 108) of the lesions progressed when analyzed with the CaLS, WORMS, and BLOKS systems, respectively. With the CaLS system, subjects with OA risk factors had significantly higher odds of progression than did subjects without risk factors (odds ratio, 2.78; P = .005). Conclusion The CaLS system is a reproducible scoring system for cartilage lesions that yields an improved detection rate for monitoring progression when compared with detection rates of semiquantitative WORMS and BLOKS systems. © RSNA, 2014.
    Radiology 01/2014; · 6.34 Impact Factor
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    ABSTRACT: To examine the cross-sectional association of whole-knee synovitis assessed by contrast-enhanced magnetic resonance imaging (CEMRI) with radiographic tibiofemoral osteoarthritis (OA), non-CEMRI-assessed cartilage damage, and meniscal status. Multicenter Osteoarthritis Study (MOST) is a cohort study of people with or at high risk of knee OA. Subjects are a subset of MOST who volunteered for both CEMRI and non-CEMRI. Using CEMRI, synovitis was assessed at 11 sites and graded 0-2 at each site. Presence of "whole-knee synovitis" was defined as the synovitis score of ≥ 1 at any site from each knee. Cartilage and meniscal damage was evaluated using non-CEMRI based on the Whole Organ MRI Score. Logistic regression was used to assess associations of synovitis with radiographic OA (Kellgren-Lawrence grade ≥ 2), widespread cartilage damage, and meniscal damage, adjusting for age, sex, and body mass index (BMI). Additional analyses were performed excluding subjects who had chondrocalcinosis on radiography and those taking antiinflammatory medications. Four hundred four subjects were included (mean age 58.8 ± 7.0 yrs, BMI 29.6 ± 4.9 kg/m2, 45.5% women). On CEMRI, the maximum synovitis score across 11 sites in each knee was 0 in 106 knees (26.2%), 1 in 135 (33.4%), and 2 in 163 (40.4%). Synovitis was associated with radiographic OA [adjusted OR (aOR) 3.25, 95% CI 1.98-5.35] and widespread cartilage damage (aOR 1.91, 95% CI 1.24-2.92). Severe meniscal damage showed a borderline significant association with synovitis (aOR 1.74, 95% CI 0.99-3.04). Additional analyses as described did not notably change the results. CEMRI-detected synovitis is strongly associated with tibiofemoral radiographic OA and MRI-detected widespread cartilage damage.
    The Journal of Rheumatology 01/2014; · 3.26 Impact Factor
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    ABSTRACT: Objective Lateral tibiofemoral osteoarthritis (OA) is overall less common than medial tibiofemoral OA, but it is more prevalent in women. This may be explained by sex differences in hip and pelvic geometry. The aim of this study is to explore sex differences in hip and pelvic geometry and determine if such parameters are associated with the presence of compartment-specific knee OA. Methods This case-control study reports on 1,328 hips/knees from 664 participants and is an ancillary to the Multicenter Osteoarthritis Study (MOST). Of the 1,328 knees, 219 had lateral OA, 260 medial OA, and 849 no OA. Hip and pelvic measurements were taken from full-limb radiographs on the ipsilateral side of the knee of interest. After adjusting for covariates, means were compared between sexes and also between knees with medial and lateral OA versus no OA using separate regression models. Results Women were shown to have a reduced femoral offset (mean 40.9mm vs. 45.9mm; p=0.001) and more valgus neck-shaft angle (mean 128.4° vs. 125.9°; p<0.001) compared to men. Compared to those with no OA, knees with lateral OA were associated with a reduced femoral offset (p=0.012), increased height of hip centre (p=0.003), more valgus neck-shaft angle (p=0.042), and increased abductor angle (p=0.031). Knees with medial OA were associated with a more varus neck-shaft angle (p=0.043) and a decreased abductor angle (p=0.003). Conclusion These data suggest anatomical variations at the hip and pelvis are associated with compartment-specific knee OA and may help to explain sex differences in patterns of knee OA.
    Osteoarthritis and Cartilage 01/2014; · 4.26 Impact Factor
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    ABSTRACT: Objective To determine whether women experience greater knee pain severity than men at equivalent levels of radiographic knee osteoarthritis (OA). Design and Methods A cross-sectional analysis of 2712 individuals (60% women) without knee replacement or a recent steroid injection. Sex differences in pain severity at each KL grade were assessed by knee using VAS scale and WOMAC with and without adjustment for age, analgesic use, BMI, clinic site, comorbid conditions, depression score, education, race, and widespread pain (WSP) using generalized estimating equations. Effect sizes (Cohen’s d) were also calculated. Analyses were repeated in those with and without patellofemoral OA (PFOA). Results Women reported higher VAS pain at all KL grades in unadjusted analyses (d=0.21-0.31, p<0.0001-0.0038) and in analyses adjusted for all covariates except WSP (d=0.16-0.22, p<0.0001-0.0472). Pain severity differences further decreased with adjustment for WSP (d=0.10-0.18) and were significant for KL grade ≤2 (p=0.0015) and 2 (p=0.0200). Presence compared with absence of WSP was associated with significantly greater knee pain at all KL grades (d=0.32-0.52, p<0.0001-0.0008). In knees with PFOA, VAS pain severity sex differences were greater at each KL grade (d=0.45-0.62, p=0.0006-0.0030) and remained significant for all KL grades in adjusted analyses (d=0.31-0.57, p=0.0013-0.0361). Results using WOMAC were similar. Conclusions Women reported greater knee pain than men regardless of KL grade, though effect sizes were generally small. These differences increased in the presence of PFOA. The strong contribution of WSP to sex differences in knee pain suggests that central sensitivity plays a role in these differences.
    Osteoarthritis and Cartilage 01/2014; · 4.26 Impact Factor
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    ABSTRACT: Objective Knee buckling, in which a knee gives way during weight-bearing, is common in people with knee pain and knee osteoarthritis (OA), but little is known about the prevalence of sensations of knee instability, slipping or shifting in which the knee does not actually buckle, or of the psychosocial and physical consequences of these symptoms. Design We asked participants in the Multicenter Osteoarthritis Study separately about episodes of knee buckling and sensations of knee instability without buckling in the past 3 months, and assessed fear of falling, poor balance confidence (ABC Balance Scale ≤ 67/100), activity limitation due to concern about buckling, and poor physical function (WOMAC physical function ≥ 28/68). We used Poisson regression to estimate prevalence ratios for cross-sectional associations of buckling and sensations of instability without buckling with these outcomes, adjusting for confounders. Results Of 2,120 participants (60% female, 40% ≥ 65 years, mean BMI: 31 kg/m258), 18% reported buckling, 27% had sensations of knee instability without buckling, and 9% reported both symptoms. Buckling and sensations of instability without buckling were each significantly associated with fear of falling, poor balance confidence, activity limitations, and poor WOMAC physical function. Subjects who reported both buckling and instability without buckling and those with at least 2 buckling episodes (15%) had the strongest association with poor outcomes. Conclusions Knee buckling and especially sensations of knee instability without buckling were common and each was significantly associated with fear of falling, poor balance confidence, activity limitations, and poor physical function.
    Osteoarthritis and Cartilage 01/2014; · 4.26 Impact Factor
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    ABSTRACT: To investigate whether objectively measured time spent in light intensity physical activity is related to incident disability and to disability progression. Prospective multisite cohort study from September 2008 to December 2012. Baltimore, Maryland; Columbus, Ohio; Pittsburgh, Pennsylvania; and Pawtucket, Rhode Island, USA. Disability onset cohort of 1680 community dwelling adults aged 49 years or older with knee osteoarthritis or risk factors for knee osteoarthritis; the disability progression cohort included 1814 adults. Physical activity was measured by accelerometer monitoring. Disability was ascertained from limitations in instrumental and basic activities of daily living at baseline and two years. The primary outcome was incident disability. The secondary outcome was progression of disability defined by a more severe level (no limitations, limitations to instrumental activities only, 1-2 basic activities, or ≥3 basic activities) at two years compared with baseline. Greater time spent in light intensity activities had a significant inverse association with incident disability. Less incident disability and less disability progression were each significantly related to increasing quartile categories of daily time spent in light intensity physical activities (hazard ratios for disability onset 1.00, 0.62, 0.47, and 0.58, P for trend=0.007; hazard ratios for progression 1.00, 0.59, 0.50, and 0.53, P for trend=0.003) with control for socioeconomic factors (age, sex, race/ethnicity, education, income) and health factors (comorbidities, depressive symptoms, obesity, smoking, lower extremity pain and function, and knee assessments: osteoarthritis severity, pain, symptoms, prior injury). This finding was independent of time spent in moderate-vigorous activities. These prospective data showed an association between greater daily time spent in light intensity physical activities and reduced risk of onset and progression of disability in adults with osteoarthritis of the knee or risk factors for knee osteoarthritis. An increase in daily physical activity time may reduce the risk of disability, even if the intensity of that additional activity is not increased.
    BMJ (online) 01/2014; 348:g2472. · 17.22 Impact Factor
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    ABSTRACT: OBJECTIVE To examine the association between sedentary behavior and BP among Osteoarthritis Initiative (OAI) participants. DESIGN We conducted a cross-sectional analysis of the OAI 48-month visit participants whose physical activity was measured using accelerometers. Participants were classified into four quartiles according to the percentage of wear time that was sedentary (<100 activity counts per minute). Users of antihypertensive medications or NSAIDs were excluded. Our main outcomes were systolic and diastolic blood pressures (SBP and DBP) and “elevated BP” defined as BP ≥ 130/85 mm Hg. RESULTS For this study cohort (N = 707), mean BP was 121.4 ± 15.6/74.7 ± 9.5 mm Hg and 33% had elevated BP. SBP had a graded association with increased sedentary time (P for trend = 0.02). The most sedentary quartile had 4.26 mm Hg higher SBP (95% CI, 0.69 – 7.82; p = 0.02) than the least sedentary quartile, adjusting for age, moderate-to-vigorous (MV) physical activity, and other demographic and health factors. The probability of having elevated BP significantly increased in higher sedentary quartiles (P for trend = 0.046). There were no significant findings for DBP. CONCLUSION A strong graded association was demonstrated between sedentary behavior and increased SBP and elevated BP, independent of time spent in MV physical activity. Reducing daily sedentary time may lead to improvement in blood pressure and reduction in cardiovascular risk.
    Osteoarthritis and Cartilage 01/2014; · 4.26 Impact Factor
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    ABSTRACT: Poor functional outcomes post-knee replacement are common, but estimates of its prevalence vary, likely in part because of differences in methods used to assess function. The agreement between improvement in function and absolute good levels of function after knee replacement has not been evaluated. We evaluated the attainment of improvement in function and absolute good function after total knee replacement (TKR) and the agreement between these measures. Using data from The Multicenter Osteoarthritis (MOST) Study, we determined the prevalence of achieving a minimal clinically important improvement (MCII, ≥ 14.2/68 point improvement) and Patient Acceptable Symptom State (PASS, ≤ 22/68 post-TKR score) on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Physical Function subscale at least 6 months after knee replacement. We also assessed the frequency of co-occurrence of the 2 outcomes, and the prevalence according to pre-knee replacement functional status. We included 228 subjects who had a knee replacement during followup (mean age 65 yrs, mean body mass index 33.4, 73% female). Seventy-one percent attained the PASS for function after knee replacement, while only 44% attained the MCII. Of the subjects who met the MCII, 93% also attained the PASS; however, of subjects who did not meet the MCII, 54% still achieved a PASS. Baseline functional status was associated with attainment of each MCII and PASS. There was only partial overlap between attainment of a good level of function and actually improving by an acceptable amount. Subjects were more likely to attain an acceptable level of function than to achieve a clinically important amount of improvement post-knee replacement.
    The Journal of Rheumatology 12/2013; · 3.26 Impact Factor
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    ABSTRACT: Objective To evaluate the association of metabolic risk factors with severity and 2-year progression of early degenerative cartilage changes at the knee, measured with T2 relaxation times in middle-aged subjects from the Osteoarthritis Initiative. Methods Cartilage segmentation and T2 map generation were performed in knee 3T magnetic resonance images from 403 subjects ages 45–60 years without radiographic osteoarthritis (OA). The influence of risk factors on baseline T2 and longitudinal progression of T2 was analyzed using linear regression, adjusting for age, sex, and other OA risk factors. ResultsFour metabolic risk factors, i.e., high abdominal circumference (P < 0.001), hypertension (P = 0.041), high fat consumption (P = 0.023), and self-reported diabetes mellitus (P = 0.010), were individually associated with higher baseline T2. When the 4 metabolic risk factors were considered in a multivariate regression model, higher T2 remained significantly associated with abdominal circumference (P < 0.001) and diabetes mellitus (P = 0.026), and there was a trend for high fat consumption (P = 0.096). For the individual risk factors, only diabetes mellitus remained associated with higher baseline T2 after adjustment for body mass index (BMI). After adjustment for BMI, baseline T2 increased in a dose-response manner with the number of metabolic risk factors present (P = 0.032 for linear trend), and subjects with ≥3 metabolic factors (versus <3) had significantly higher baseline T2 (mean difference 1.2 msec [95% confidence interval 0.3, 2.1]; P = 0.011). Metabolic risk factors were not significantly associated with increases in T2 during followup. Conclusion Metabolic risk factors are associated with higher T2, suggesting that increased cartilage degeneration may be caused by modifiable metabolic disorders.
    Arthritis Care & Research. 12/2013; 65(12).
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    ABSTRACT: OBJECTIVE To determine whether older adults with diabetes are at increased risk of an injurious fall requiring hospitalization.RESEARCH DESIGN AND METHODS The longitudinal Health, Aging, and Body Composition Study included 3,075 adults aged 70-79 years at baseline. Hospitalizations that included ICD-9-Clinical Modification codes for a fall and an injury were identified. The effect of diabetes with and without insulin use on the rate of first fall-related injury hospitalization was assessed using proportional hazards models.RESULTSAt baseline, 719 participants had diabetes, and 117 of them were using insulin. Of the 293 participants who were hospitalized for a fall-related injury, 71 had diabetes, and 16 were using insulin. Diabetes was associated with a higher rate of injurious fall requiring hospitalization (hazard ratio [HR] 1.48 [95% CI 1.12-1.95]) in models adjusted for age, race, sex, BMI, and education. In those participants using insulin, compared with participants without diabetes, the HR was 3.00 (1.78-5.07). Additional adjustment for potential intermediaries, such as fainting in the past year, standing balance score, cystatin C level, and number of prescription medications, accounted for some of the increased risk associated with diabetes (1.41 [1.05-1.88]) and insulin-treated diabetes (2.24 [1.24-4.03]). Among participants with diabetes, a history of falling, poor standing balance score, and A1C level ≥8% were risk factors for an injurious fall requiring hospitalization.CONCLUSIONS Older adults with diabetes, in particular those using insulin, are at greater risk of an injurious fall requiring hospitalization than those without diabetes. Among those with diabetes, poor glycemic control may increase the risk of an injurious fall.
    Diabetes care 10/2013; · 7.74 Impact Factor
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    ABSTRACT: To study the natural evolution of cartilage T2 relaxation times in knees with various extents of morphological cartilage abnormalities, assessed with 3 Tesla MRI from the Osteoarthritis Initiative. Right knee MRIs of 245, 45- to 60-year-old individuals without radiographic osteoarthritis (OA) were included. Cartilage was segmented and T2 maps were generated in five compartments (patella, medial and lateral femoral condyle, medial, and lateral tibia) at baseline and 2-year follow-up. We examined the association of T2 values and 2-year change of T2 values with various Whole-Organ MR Imaging Scores (WORMS). Statistical analysis was performed with analysis of variance and Students t-tests. Higher baseline T2 was associated with more severe cartilage defects at baseline and subsequent cartilage loss (P < 0.001). However, longitudinal T2 change was inversely associated with both baseline (P = 0.038) and follow-up (P = 0.002) severity of cartilage defects. Knees that developed new cartilage defects had smaller increases in T2 than subjects without defects (P = 0.045). Individuals with higher baseline T2 showed smaller T2 increases over time (P < 0.001). An inverse correlation of longitudinal T2 changes versus baseline T2 values and morphological cartilage abnormalities suggests that once morphological cartilage defects occur, T2 values may be limited for evaluating further cartilage degradation.J. Magn. Reson. Imaging 2013. © 2013 Wiley Periodicals, Inc.
    Journal of Magnetic Resonance Imaging 09/2013; · 2.57 Impact Factor
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    ABSTRACT: To determine whether quadriceps weakness is associated with elevated risk of worsening knee pain over 5 years. The Multicenter Osteoarthritis Study (MOST) is a longitudinal study of 50-79-year-old adults with knee osteoarthritis (OA) or known risk factors for knee OA. The predictor variable was baseline isokinetic quadriceps strength. Covariates included baseline body mass index (BMI), physical activity level, and history of knee surgery. The outcome was worsening pain reported on the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index pain subscale or knee replacement surgery between baseline and 5-year follow-up. Analyses were knee-based and used generalized estimating equations, stratified by sex to assess whether the lowest compared with the highest tertile of baseline quadriceps strength was associated with an increased risk of worsening knee pain at 5-year follow-up, controlling for age, BMI, history of knee surgery, and physical activity level as well as correlation between knees within participants. Analyses of worsening knee pain included 4,648 knees from 2,404 participants (61% female). Men with lower quadriceps strength did not have a higher risk of worsening knee pain (RR {95% CI} = 1.01 {0.78-1.32}, P = 0.9183). However, women in the lowest compared with the highest strength tertile had a 28% increased risk of worsening knee pain (RR {95% CI} = 1.28 {1.08-1.52}, P = 0.0052). Quadriceps weakness was associated with an increased risk of worsening of knee pain over 5 years in women, but not in men.
    Osteoarthritis and Cartilage 09/2013; 21(9):1154-9. · 4.26 Impact Factor

Publication Stats

25k Citations
2,243.24 Total Impact Points


  • 2014
    • University of San Francisco
      San Francisco, California, United States
  • 1989–2014
    • University of California, San Francisco
      • • Department of Epidemiology and Biostatistics
      • • Department of Radiology and Biomedical Imaging
      • • Division of Rheumatology
      • • Division of Prevention Science
      • • Division of General Internal Medicine
      • • Division of Hospital Medicine
      San Francisco, California, United States
  • 2013
    • Technische Universität München
      München, Bavaria, Germany
    • The University of Manchester
      Manchester, England, United Kingdom
    • University of Minnesota Duluth
      Duluth, Minnesota, United States
    • Hospital for the Heart
      San Paulo, São Paulo, Brazil
  • 2007–2013
    • University of Iowa
      • Department of Orthopaedics and Rehabilitation
      Iowa City, Iowa, United States
  • 2004–2013
    • Boston University
      • • Department of Radiology
      • • Section of Clinical Epidemiology
      Boston, Massachusetts, United States
    • University of Minnesota Twin Cities
      • School of Public Health
      Minneapolis, MN, United States
  • 2003–2013
    • National Institute on Aging
      • • Laboratory of Epidemiology, Demography and Biometry (LEDB)
      • • Clinical Research Branch (CRB)
      Baltimore, Maryland, United States
    • The University of Tennessee Health Science Center
      • • Division of Biostatistics and Epidemiology
      • • Department of Preventive Medicine
      Memphis, Tennessee, United States
    • Overton Brooks VA Medical Center
      Shreveport, Louisiana, United States
    • Peking Union Medical College Hospital
      • Department of Obstetrics and Gynecology
      Beijing, Beijing Shi, China
  • 2012
    • The Prevention Group
      Omaha, Nebraska, United States
  • 2001–2012
    • University of Massachusetts Boston
      • Clinical Epidemiology Research and Training Unit
      Boston, MA, United States
  • 2011
    • University of Oxford
      Oxford, England, United Kingdom
    • Harvard Medical School
      Boston, Massachusetts, United States
  • 2009–2011
    • Lund University
      Lund, Skåne, Sweden
    • Wake Forest School of Medicine
      • Sticht Center on Aging
      Winston-Salem, NC, United States
  • 1997–2011
    • CSU Mentor
      Long Beach, California, United States
    • Permanente Medical Group
      Pasadena, California, United States
    • University of Sydney
      Sydney, New South Wales, Australia
  • 2010
    • University of California, Davis
      Davis, California, United States
  • 2007–2010
    • California Pacific Medical Center Research Institute
      • Research Institute
      San Francisco, CA, United States
  • 2008–2009
    • Boston Medical Center
      Boston, Massachusetts, United States
  • 1993–2009
    • University of Pittsburgh
      • • Department of Epidemiology
      • • Department of Orthopaedic Surgery
      Pittsburgh, Pennsylvania, United States
  • 2006
    • University of Southampton
      Southampton, England, United Kingdom
  • 2005
    • Park Nicollet Health Services
      Minneapolis, Minnesota, United States
    • University of Queensland 
      • School of Human Movement Studies
      Brisbane, Queensland, Australia
    • U.S. Department of Veterans Affairs
      • Geriatric Research, Education and Clinical Center (GRECC)
      Washington, Washington, D.C., United States
  • 2000–2005
    • VU University Amsterdam
      • • Faculty of Earth and Life Sciences
      • • Faculty of Medicine/VU University Medical Center
      Amsterdam, North Holland, Netherlands
  • 1999–2003
    • University of California, Los Angeles
      • • Division of Geriatrics
      • • Department of Medicine
      Los Angeles, CA, United States
  • 2002
    • Minneapolis Veterans Affairs Hospital
      Minneapolis, Minnesota, United States
    • Centers for Disease Control and Prevention
      • Division of Diabetes Translation
      Druid Hills, GA, United States
  • 1998–1999
    • Stanford University
      • Department of Health Research and Policy
      Palo Alto, CA, United States
  • 1990–1996
    • Columbia University
      • Department of Epidemiology
      New York City, NY, United States
  • 1994
    • Kaiser Permanente
      • Center for Health Research (Oregon, Hawaii, and Georgia)
      Oakland, California, United States
    • Oregon Health and Science University
      • Division of General Internal Medicine
      Portland, OR, United States