Search

ObjectiveTo investigate the public health impact of obesity and other modifiable risk factors related to physical inactivity in adults with knee osteoarthritis (OA).MethodsThe frequency of inactivity as defined by the US Department of Health and Human Services was assessed from objective accelerometer monitoring of 1,089 participants (ages 49-84 years) with radiographic knee OA during the Osteoarthritis Initiative 48-month visit (2008-2010). The relationship between modifiable factors (weight status, dietary fat, fiber, smoking, depressive symptoms, knee function, knee pain, and knee confidence) with inactivity was assessed using odds ratios (ORs) and attributable fractions (AFs), controlling for descriptive factors (age, sex, race, education, lives alone, employment, frequent knee symptoms, and comorbidity).ResultsAlmost half (48.9%) of participants with knee OA were inactive. Being overweight (OR 1.8, 95% confidence interval [95% CI] 1.2-2.5) or obese (OR 3.9, 95% CI 2.6-5.7), having inadequate dietary fiber intake (OR 1.6, 95% CI 1.2-2.2), severe knee dysfunction (OR 1.9, 95% CI 1.3-2.8), and severe pain (OR 1.7, 95% CI 1.1-2.5) were significantly related to inactivity, controlling for descriptive factors. Modifiable factors with significant average AFs were being overweight or obese (AF 23.8%, 95% CI 10.5-38.6%) and inadequate dietary fiber (AF 12.1%, 95% CI 0.1-24.5%), controlling for all factors.ConclusionBeing obese or overweight, the quality of the diet, severe pain, and severe dysfunction are significantly associated with physical inactivity in adults with knee OA. All components should be considered in designing physical activity interventions that target arthritis populations with low activity levels.

Objective: Many patients with rheumatoid arthritis (RA) experience sleep disturbances, commonly attributed to joint pain. Sleep disturbances could also influence pain. One mechanism may be through dysregulated pain processing, manifested by enhanced pain sensitivity. The present study was undertaken to examine the role of pain sensitization, measured by quantitative sensory testing (QST), as a mediator in the pathway of sleep disturbance leading to subsequent pain. Methods: We used longitudinal data from 221 patients with active RA who were followed for 12 weeks after initiating a disease‐modifying antirheumatic drug. Baseline QST included pressure pain thresholds at articular (wrists, knees) and nonarticular (trapezius, thumbnails) sites, temporal summation (TS) at the wrist and forearm, and conditioned pain modulation (CPM). Baseline sleep disturbance and subsequent pain intensity were assessed using the Patient‐Reported Outcomes Measurement Information System (PROMIS). We evaluated correlations between sleep disturbance, QSTs, and subsequent pain intensity. Mediation analyses separately assessed each QST as a mediator, adjusting for baseline confounding factors. Results: Sleep disturbance was correlated with all QST measures except wrist TS and CPM. Sleep disturbance significantly predicted subsequent pain (coefficient for a meaningful increase of 5 units in sleep disturbance = 0.32 (95% confidence interval 0.11, 0.50) in multiple regression. QST mediated 10–19% of this effect. Conclusion: Pain sensitization may be one mechanism through which sleep disturbance contributes to pain. The small magnitude of association indicates that unmeasured pathways may contribute to this relationship. Intervention studies are needed to establish causality and determine whether improving sleep can improve pain in patients with RA. [ABSTRACT FROM AUTHOR]

Objective: Despite the numerous health benefits of physical activity, inactivity is endemic among adults with knee osteoarthritis (OA). Because sleep quality may be a target in order to improve physical activity behavior, we investigated the cross‐sectional relationship between restless sleep and physical activity in participants with or at risk for knee OA. Methods: We analyzed accelerometer‐measured physical activity and clinical data of participants included in the Osteoarthritis Initiative (OAI). We used multiple regression analysis to evaluate physical activity for participants, who were grouped by the reported frequency of restless sleep, and adjusted for demographic and medical confounders. Results: Of the 1,892 OAI participants for whom complete data were available, 300 participants (16%) reported restless sleep ≥3 days in the past week. Participants who reported restless sleep for much of the time (3–4 days/week) and most of the time (5–7 days/week) had 11.9% and 23.7% less weekly minutes of moderately vigorous activity, respectively, compared to participants who reported rarely restless sleep (<1 day/week) (P for trend 0.021). These differences persisted after accounting for age, sex, race, body mass index, medical comorbidity, and knee OA severity and pain (P for trend 0.023). Differences related to restless sleep were largely attenuated by the presence of high depressive symptoms and low energy levels. Conclusion: Poor sleep quality is associated with less physical activity in persons with or at risk for knee OA. Future studies are needed to determine the mechanisms of how poor sleep and physical activity are related, how energy and depression mediate these relationships, and whether interventions that improve sleep quality might result in increased physical activity. [ABSTRACT FROM AUTHOR]

Objective This cross-sectional study examined racial/ethnic differences in meeting the 2008 United States Department of Health and Human Services Physical Activity Guidelines aerobic component (≥150 moderate-to-vigorous minutes/week in bouts of ≥10 minutes) among persons with or at risk of radiographic knee osteoarthritis (RKOA). Methods We evaluated African American versus white differences in guideline attainment using multiple logistic regression, adjusting for sociodemographic (age, sex, site, income, and education) and health factors (comorbidity, depressive symptoms, overweight/obesity, and knee pain). Our analyses included adults ages 49-84 years who participated in accelerometer monitoring at the Osteoarthritis Initiative 48-month visit (n = 1,142 with RKOA and n = 747 at risk of RKOA). Results Two percent of African Americans and 13.0% of whites met the guidelines. For adults with and at risk of RKOA, significantly lower rates of guidelines attainment among African Americans compared to whites were partially attenuated by health factor differences, particularly overweight/obesity and knee pain (with RKOA: adjusted odds ratio [OR] 0.24, 95% confidence interval [95% CI] 0.08-0.72; at risk of RKOA: OR 0.28, 95% CI 0.07-1.05). Conclusion Despite known benefits from physical activity, attainment of the physical activity guidelines among persons with and at risk of RKOA was low. African Americans were 72-76% less likely than whites to meet the guidelines. Culturally relevant interventions and environmental strategies in the African American community targeting overweight/obesity and knee pain may reduce future racial/ethnic differences in physical activity and improve health outcomes. [ABSTRACT FROM AUTHOR]

Objective We evaluated whether African Americans in the Osteoarthritis Initiative (OAI) have a greater risk (versus whites) of poor 4-year function outcome within strata defined by sex, body mass index (BMI), and waist circumference. Methods Using Western Ontario and McMaster Universities Osteoarthritis Index function, 20-meter walk, and chair stand performance, poor outcome was defined as moving into a worse function group or remaining in the 2 worst groups over 4 years. Logistic regression was used to evaluate the relationship between racial group and outcome within each stratum, adjusting for age, education, and income, and then further adjusting for BMI, comorbidity, depressive symptoms, physical activity, knee pain, and osteoarthritis (OA) severity. Results In 3,695 persons with or at higher risk for knee OA, higher BMI and large waist circumference were each associated with poor outcome. Among women with high BMI and among women with large waist circumference, African Americans were at greater risk for poor outcome by every measure, adjusting for age, education, and income. From fully adjusted models, potential explanatory factors included income, comorbidity, depressive symptoms, pain, and disease severity. Findings were less consistent for men, emerging only for the 20-meter walk or chair stand outcomes, and potentially explained by age and knee pain. Conclusion Among OAI women with excess body weight, African Americans are at greater risk than whites for poor 4-year outcome. Modifiable factors that may help to explain these findings in the OAI include comorbidity, depressive symptoms, and knee pain. Targeting such factors, while supporting weight loss, may help to lessen the outcome disparity between African American and white women. [ABSTRACT FROM AUTHOR]