Summary Objective To assess the associations of atrophic tibiofemoral osteoarthritis (OA) with progression of radiographic joint space narrowing (JSN) and magnetic resonance imaging (MRI)-defined ...progression of cartilage damage. Design Participants of the Multicenter Osteoarthritis (MOST) Study with available radiographic and MRI assessments at baseline and 30 months were included. The atrophic OA phenotype was defined as OARSI grades 1 or 2 for JSN and grade 0 for osteophytes. Based on MRI, atrophic OA was defined as tibiofemoral (TF) cartilage damage grades ≥3 in at least 2 of 10 subregions with absent or tiny osteophytes in all TF subregions. Progression of JSN and cartilage loss on MRI, was defined as (1) no, (2) slow, and (3) fast progression. Co-variance and logistic regression with generalized estimated equations were performed to assess the association of atrophic knee OA with any progression, compared to non-atrophic OA knees. Results A total of 476 knees from 432 participants were included. There were 50 (10.5%) knees with atrophic OA using the radiographic definition, and 16 (3.4%) knees with atrophic OA using MRI definition. Non-atrophic OA knees more commonly exhibited fast progression of JSN and cartilage damage. Logistic regression showed that the atrophic phenotype of knee OA was associated with a decreased likelihood of progression of JSN and cartilage loss. Conclusion In this sample, the atrophic phenotype of knee OA was associated with a decreased likelihood of progression of JSN and cartilage loss compared to the non-atrophic knee OA phenotype.
Objective
To examine whether obesity increases the risk of progression of knee osteoarthritis (OA).
Methods
We used data from the Multicenter Osteoarthritis Study, a longitudinal study of persons ...with or at high risk of knee OA. OA was characterized at baseline and 30 months using posteroanterior fixed‐flexion radiographs and Kellgren/Lawrence (K/L) grading, with alignment assessed on full‐extremity films. In knees with OA at baseline (K/L grade 2 or 3), progression was defined as tibiofemoral joint space narrowing on the 30‐month radiograph. In knees without OA at baseline (K/L grade 0 or 1), incident OA was defined as the development of radiographic OA at 30 months. Body mass index (BMI) at baseline was classified as normal (<25 kg/m2), overweight (25–<30 kg/m2), obese (30–<35 kg/m2), and very obese (≥35 kg/m2). The risk of progression was tested in all knees and in subgroups categorized according to alignment. Analyses were adjusted for age, sex, knee injury, and bone density.
Results
Among the 2,623 subjects (5,159 knees), 60% were women, and the mean ± SD age was 62.4 ± 8.0 years. More than 80% of subjects were overweight or obese. At baseline, 36.4% of knees had tibiofemoral OA, and of those, only one‐third were neutrally aligned. Compared with subjects with a normal BMI, those who were obese or very obese were at an increased risk of incident OA (relative risk 2.4 and 3.2, respectively P for trend < 0.001); this risk extended to knees from all alignment groups. Among knees with OA at baseline, there was no overall association between a high BMI and the risk of OA progression; however, an increased risk of progression was observed among knees with neutral but not varus alignment. The effect of obesity was intermediate in those with valgus alignment.
Conclusion
Although obesity was a risk factor for incident knee OA, we observed no overall relationship between obesity and the progression of knee OA. Obesity was not associated with OA progression in knees with varus alignment; however, it did increase the risk of progression in knees with neutral or valgus alignment. Therefore, weight loss may not be effective in preventing progression of structural damage in OA knees with varus alignment.
Objective
The study objective was to determine the relationship of magnetic resonance imaging (MRI)‐detected features of patellofemoral joint osteoarthritis to pain and functional outcomes.
Methods
...We sampled 1,099 participants from the 60‐month visit of the Multicenter Osteoarthritis Study (mean ± SD age: 66.8 ± 7.5 years; body mass index: 29.6 ± 4.8; 65% female). We determined the prevalence of MRI‐detected features of patellofemoral joint osteoarthritis (eg, cartilage damage, bone marrow lesions, and osteophytes) and assessed the relationship between these features and knee pain severity, knee pain on stairs, chair stand time, and walking less than 6,000 steps per day. We evaluated the relationship of MRI features to each outcome using logistic and linear regression, adjusting for potential covariates.
Results
Participants with cartilage damage in 3‐4 subregions had the highest mean pain severity (22.0/100; 95% confidence interval CI: 17.6‐26.4 mm). They also showed higher odds of having at least mild pain on stairs (odds ratio OR: 3.3; 95% CI: 1.7‐6.5) and of walking less than 6,000 steps per day (OR: 2.3; 95% CI: 1.1‐4.4) compared with those without cartilage damage. Participants with bone marrow lesions in 3‐4 subregions had higher odds of at least mild pain on stairs than those without (OR: 3.3; 95% CI: 2.2‐5.2). Participants with osteophytes in 3‐4 subregions also had higher odds of walking less than 6,000 steps/day (OR 2.1, 95% CI: 1.3‐3.5, respectively).
Conclusion
MRI‐detected features of osteoarthritis of the patellofemoral joint are related to pain and functional performance. This knowledge highlights the need to develop treatments for those with patellofemoral joint osteoarthritis to improve pain and maximize function.
Stroke imposes a substantial economic burden on individuals and society. This study estimates the lifetime direct and indirect costs associated with the three major types of stroke: subarachnoid ...hemorrhage (SAH), intracerebral hemorrhage (ICH), and ischemic stroke (ISC).
We developed a model of the lifetime cost of incident strokes occurring in 1990. An epidemiological model of stroke incidence, survival, and recurrence was developed based on a review of the literature. Data on direct cost of treating stroke were obtained from Medicare claims data, the 1987 National Medical Expenditure Survey (NMES), and insurance claims data representing a group of large, self-insured employers. Indirect costs (the value of foregone market and nonmarket production) associated with premature morbidity and mortality were estimated based on data from the US Bureau of Economic Analysis and the 1987 NMES.
The lifetime cost per person of first strokes occurring in 1990 is estimated to be $228,030 for SAH, $123,565 for ICH, $90,981 for ISC, and $103,576 averaged across all stroke sub-types. Indirect costs accounted for 58.0% of lifetime costs. Aggregate lifetime cost associated with an estimated 392,344 first strokes in 1990 was $40.6 billion: $5.6 billion for SAH, $6.0 billion for ICH, and $29.0 billion for ISC. Acute-care costs incurred in the 2 years following a first stroke accounted for 45.0%, long-term ambulatory care accounted for 35.0%, and nursing home costs accounted for 17.5% of aggregate lifetime costs of stroke.
The lifetime cost of stroke varies considerably by type of stroke and entails considerable costs beyond the first 2 years after a stroke.
Previous studies have shown that alendronate can increase bone mineral density (BMD) and prevent radiographically defined (morphometric) vertebral fractures. The Fracture Intervention Trial aimed to ...investigate the effect of alendronate on the risk of morphometric as well as clinically evident fractures in postmenopausal women with low bone mass.
Women aged 55–81 with low femoral-neck BMD were enrolled in two study groups based on presence or absence of an existing vertebral fracture. Results for women with at least one vertebral fracture at baseline are reported here. 2027 women were randomly assigned placebo (1005) or alendronate (1022) and followed up for 36 months. The dose of alendronate (initially 5 mg daily) was increased (to 10 mg daily) at 24 months, with maintenance of the double blind. Lateral spine radiography was done at baseline and at 24 and 36 months. New vertebral fractures, the primary endpoint, were defined by morphometry as a decrease of 20% (and at least 4 mm) in at least one vertebral height between the baseline and latest follow-up radiograph. Non-spine clinical fractures were confirmed by radiographic reports. New symptomatic vertebral fractures were based on self-report and confirmed by radiography.
Follow-up radiographs were obtained for 1946 women (98% of surviving participants). 78 (8·0%) of women in the alendronate group had one or more new morphometric vertebral fractures compared with 145 (15·0%) in the placebo group (relative risk 0·53 95% CI 0·41–0·68). For clinically apparent vertebral fractures, the corresponding numbers were 23 (2·3%) alendronate and 50 (5·0%) placebo (relative hazard 0·45 0·27–0·72). The risk of any clinical fracture, the main secondary endpoint, was lower in the alendronate than in the placebo group (139 13·6%
vs 183 18·2%; relative hazard 0·72 0·58–0·90). The relative hazards for hip fracture and wrist fracture for alendronate versus placebo were 0·49 (0·23–0·99) and 0·52 (0·31–0·87). There was no significant difference between the groups in numbers of adverse experiences, including upper-gastrointestinal disorders.
We conclude that among women with low bone mass and existing vertebral fractures, alendronate is well tolerated and substantially reduces the frequency of morphometric and clinical vertebral fractures, as well as other clinical fractures.
Summary Purpose To determine the association of MRI-assessed worsening of tibiofemoral cartilage damage, meniscal damage, meniscal extrusion, separately and together, with progression of radiographic ...joint space narrowing (JSN). Method and materials The Multicenter Osteoarthitis Study (MOST) Study is a cohort study of subjects with or at risk for knee osteoarthritis (OA). Knees with radiographic OA Kellgren–Lawrence grade 2 at baseline and with baseline and 30-month 1.0T MRIs were selected for reading using the WORMS system for cartilage damage, meniscal damage, and meniscal extrusion. The association of worsening of cartilage damage, meniscal damage, and/or meniscal extrusion with increases in the JSN was performed using logistic regression. Results A total of 276 knees (one per subject) were included (women 68.5%, mean age 62.9 ± 7.8, mean body mass index (BMI) 30.2 ± 5.0). Worsening of each MRI feature was associated with any increase in JSN ( P < 0.01). Worsening of cartilage damage was more frequently observed than worsening of meniscal damage and extrusion, and was significantly associated with both slow and fast progression of JSN. An increasing risk of JSN worsening was associated with increasing number of worsening MRI features ( P for trend < 0.0001). Conclusion Worsening of tibiofemoral cartilage damage, meniscal damage, and meniscal extrusion are independent predictors of JSN progression in the same compartment. Worsening of cartilage damage is more frequently observed in JSN when compared to meniscal worsening. A strong cumulative effect on JSN progression is observed for worsening of more than one MRI feature.
Controversy persists concerning the impact of community water fluoridation on bone health in adults, and few studies have assessed relationships with bone at younger ages. Ecological studies of ...fluoride’s effects showed some increase in bone mineral density of adolescents and young adults in areas with fluoridated water compared with non-fluoridated areas. However, none had individual fluoride exposure measures. To avoid ecological fallacy and reduce bias, we assessed associations of average daily fluoride intake from birth to age 15 yr for Iowa Bone Development Study cohort members with age 15 yr dual-energy x-ray absorptiometry (DXA) bone outcomes (whole body, lumbar spine, and hip), controlling for known determinants (including daily calcium intake, average daily time spent in moderate-to-vigorous intensity physical activity, and physical maturity). Mean (SD) daily fluoride intake was 0.66 mg (0.24) for females and 0.78 mg (0.30) for males. We found no significant relationships between daily fluoride intake and adolescents’ bone measures in adjusted models (for 183 females, all p values ≥ .10 and all partial R2 ≤ 0.02; for 175 males, all p values ≥ .34 and all partial R2 ≤ 0.01). The findings suggest that fluoride exposures at the typical levels for most US adolescents in fluoridated areas do not have significant effects on bone mineral measures.
To examine factors associated with blood exposure and percutaneous injury among health care workers, we assessed occupational risk factors, compliance with standard precautions, frequency of ...exposure, and reporting in a stratified random sample of 5123 physicians, nurses, and medical technologists working in Iowa community hospitals. Of these, 3223 (63%) participated. Mean rates of hand washing (32%–54%), avoiding needle recapping (29%–70%), and underreporting sharps injuries (22%–62%; overall, 32%) varied by occupation (P < .01). Logistic regression was used to estimate the adjusted odds of percutaneous injury (aORinjury), which increased 2%–3% for each sharp handled in a typical week. The overall aORinjury for never recapping needles was 0.74 (95% CI, 0.60–0.91). Any recent blood contact, a measure of consistent use of barrier precautions, had an overall aORinjury of 1.57 (95% CI, 1.32–1.86); among physicians, the aORinjury was 2.18 (95% CI, 1.34–3.54). Adherence to standard precautions was found to be suboptimal. Underreporting was found to be common. Percutaneous injury and mucocutaneous blood exposure are related to frequency of sharps handling and inversely related to routine standard-precaution compliance. New strategies for preventing exposures, training, and monitoring adherence are needed.
Summary Objective Radiographic disease and knee pain are thought to decrease physical activity in people with knee osteoarthritis (OA), but this has not been formally studied. We examined change in ...objectively measured daily walking over 2 years and evaluated the association of certain risk factors with reduced walking among adults with or at risk of knee OA. Design Steps/day over 7 days were collected at baseline and 2 years later in subjects with or at risk of knee OA from the Multicenter Osteoarthritis Study using a StepWatch. We evaluated the presence of radiographic knee osteoarthritis (ROA), knee pain, worsening of ROA and pain over 2 years, obesity, depressive symptoms, living situation, catastrophizing, fatigue, widespread pain and comorbidities with 2-year change in daily walking using regression models adjusted for potential confounders. Results 1318 met inclusion criteria (age 66.9 ± 7.7, 59% women, BMI 30.6 ± 5.9) and walked 126 ± 1700 steps/day fewer steps at 2 years (95% CI −218, −35). People with depressive symptoms at baseline walked 455 fewer steps/day −872, −68, and there was a trend for people with ROA worsening to walk 183 fewer steps/day −377.5, 11.7. No other factors met statistical significance for change in daily walking. Conclusion Adults with or at risk of knee OA experienced only minimal declines in daily walking over 2 years. Nonetheless, depressive symptoms and may be worsening ROA are associated with a decline in steps/day in adults with or at risk of knee OA.
PDF
