C. Kent Kwoh

Hyperuricemia and Incidence of Hypertension Among Men Without Metabolic Syndrome

The aim of this project was to study the risk of developing hypertension over a 6-year follow-up in normotensive men with baseline hyperuricemia (serum uric acid >7.0 mg/dL) but without diabetes/glucose intolerance or metabolic syndrome. We analyzed the data on men without metabolic syndrome or hypertension at baseline from the Multiple Risk Factor Intervention Trial. These men (n=3073; age: 35 to 57 years) were followed for an average of 6 years by annual examinations. Follow-up blood pressure among those with baseline was consistently higher than among those with normal serum uric acid concentration. We used Cox regression models for adjustment for the effects of serum creatinine, body mass index, age, blood pressure, proteinuria, serum cholesterol and triglycerides, alcohol and tobacco use, risk factor interventions, and use of diuretics. In these models, normotensive men with baseline hyperuricemia had an 80% excess risk for incident hypertension (hazard ratio: 1.81; 95% CI: 1.59 to 2.07) compared with those who did not. Each unit increase in serum uric acid was associated with a 9% increase in the risk for incident hypertension (hazard ratio: 1.09; 95% CI: 1.02 to 1.17). We conclude that the hyperuricemia–hypertension risk relationship is present among normotensive middle-aged men without diabetes/glucose intolerance or metabolic syndrome.

Objective physical activity measurement in the osteoarthritis initiative: Are guidelines being met?†

OBJECTIVE Osteoarthritis (OA) clinical practice guidelines identify a substantial therapeutic role for physical activity, but objective information about the physical activity of this population is lacking. The aim of this study was to objectively measure levels of physical activity in adults with knee OA and report the prevalence of meeting public health physical activity guidelines. METHODS Cross-sectional accelerometry data from 1,111 adults with radiographic knee OA (49-84 years old) participating in the Osteoarthritis Initiative accelerometry monitoring ancillary study were assessed for meeting the aerobic component of the 2008 Physical Activity Guidelines for Americans (≥150 minutes/week moderate-to-vigorous-intensity activity lasting ≥10 minutes). Quantile regression was used to test median sex differences in physical activity levels. RESULTS Aerobic physical activity guidelines were met by 12.9% of men and 7.7% of women with knee OA. A substantial proportion of men and women (40.1% and 56.5%, respectively) were inactive, having done no moderate-to-vigorous activity that lasted 10 minutes or more during the 7 days. Although men engaged in significantly more moderate-to-vigorous activity (average daily minutes 20.7 versus 12.3), they also spent more time in no or very-low-intensity activity than women (average daily minutes 608.2 versus 585.8). CONCLUSION Despite substantial health benefits from physical activity, adults with knee OA were particularly inactive based on objective accelerometry monitoring. The proportions of men and women who met public health physical activity guidelines were substantially less than those previously reported based on self-reported activity in arthritis populations. These findings support intensified public health efforts to increase physical activity levels among people with knee OA.

Understanding ethnic differences in the utilization of joint replacement for osteoarthritis: The role of patient-level factors

Background. There is a marked difference between black patients and white patients in the utilization of joint replacement therapy. The reasons behind this disparity remain unknown. Objectives. To examine how black and white potential candidates for joint replacement compare with respect to their overall familiarity with joint replacement as an option, as well as their perceptions of the risks/benefits of this procedure. Methods. Cross-sectional survey of 596 elderly patients with symptomatic osteoarthritis of the knee or hip or both attending primary care clinics at Cleveland VAMC. Results. Black (44%) and white (56%) patients in this cohort were comparable with respect to age and clinical factors. However, black patients were less likely to be employed (8% vs. 15%, P = 0.017) or to be married (39% vs. 56%, P = 0.000), but more likely to report an annual household income of less than

Analgesic usage for low back pain: Impact on health care costs and service use

10,000 (41% vs. 20%, P = 0.000) and less than high school education (43% vs. 29%, P = 0.001). Black patients were less likely than white patients to have had family or friends who had had joint replacement (OR, 0.39 [0.26–0.61]), or to report a good understanding of joint replacement as a form of treatment (OR, 0.62 [0.42–0.92]). They were more likely than white patients to expect longer hospital course (OR, 4.09 [2.57–6.54]), moderate to extreme pain (OR, 2.61 [1.74–3.89]), and moderate to extreme difficulty walking after replacement surgery (OR, 2.76 [1.83–4.16]). Conclusion. Black patients were less likely than white patients to be familiar with joint replacement surgery and more likely to express concerns about postsurgical pain and difficulty walking.

Factors Associated With Patients Who Leave Acute-Care Hospitals Against Medical Advice

Study Design. Cross-sectional analysis of analgesic use by patients with low back pain (LBP). Objectives. To describe patterns of analgesic use and their cost implications for the use of other care services among individuals with LBP enrolled in a health insurance plan during 2001. It was hypothesized that the use of analgesics would be most frequent among patients with LBP with neurologic findings. Summary of Background Data. National guidelines have recommended analgesics as the primary pharmacologic treatment of LBP. The choice of specific analgesics has major cost and service use implications. Methods. The University of Pittsburgh Health System includes 18 affiliated hospitals, more than 5000 physicians, and a commercial health plan with 255,958 members in 2001. This study uses the System Health Plan’s insurance claims database to identify members who had services provided for one of 66 International Classification of Diseases, Version 9, Clinical Modification codes that identify mechanical LBP (n = 17,148). Results. In 2001, 7631 (43.5%) members with claims for LBP services had no analgesic pharmacy claims. The other 9517 (55.5%) had analgesics claims costing a total of

Variation in perceptions of treatment and self-care practices in elderly with osteoarthritis: a comparison between African American and white patients.

1.4 million; 68% of claimants were prescribed an opioid and 58% nonselective nonsteroidal antiinflammatory drugs (NSAID). The costs of opioids, NSAID, and cyclooxygenase-2 selective NSAID for patients with LBP represented 48%, 24%, and 28%, respectively, of total health plan expenditures for all uses of these drugs, including cancer. Opioid use was associated with the high volume usage of LBP care services. Patients with LBP with and without neurologic involvement and those with acquired lumbar spine structural disorders had similar patterns of analgesic use: those with congenital structural disorders were less likely to use analgesics; and those with psychogenic pain and LBP related to orthopedic devices were more likely to use opioids. Conclusions. With this health plan, a high proportion of patients with LBP had claims for opioids during 2001. The use of opioids by patients with LBP represents a major cost for the health plan, and is associated with specific patient characteristics and their use of other LBP services.

Knee Articular Cartilage Damage in Osteoarthritis: Analysis of MR Image Biomarker Reproducibility in ACRIN-PA 4001 Multicenter Trial

OBJECTIVES We examined hospital- and patient-related factors associated with discharge against medical advice (termed self-discharge) after emergency admission to acute-care hospitals. METHODS We analyzed data from the Nationwide Inpatient Sample of the Healthcare Cost and Utilization Project using logistic regression models to assess the relationship between self-discharge and a set of patient and hospital characteristics. RESULTS Of 3,039,050 discharges in the sample, 43 678 were against medical advice (1.44%). In multivariable modeling, predictors of self-discharge included having Medicaid insurance (adjusted odds ratio [AOR]=3.32; 95% confidence interval [CI]=3.22, 3.42), having Medicare insurance (AOR=1.64; 95% CI=1.59, 1.70), urban location (AOR=1.66; 95% CI=1.61, 1.72), medium (AOR=1.25; 95% CI=1.20, 1.29) or large (AOR=1.08, 95% CI=1.05, 1.12) hospital (defined by the number of beds), shorter hospital stay (OR=0.84; 95% CI=0.84, 0.85), and African American race (AOR=1.10; 95% CI=1.07, 1.14). Teaching hospitals had fewer self-discharges (AOR=0.90; 95% CI=0.88, 0.92). Other predictors of discharge against medical advice included age, gender, and income. CONCLUSIONS Approximately 1 in 70 hospital discharges in the United States are against medical advice. Both hospital and patient characteristics were associated with these decisions.

Ethnic differences in the perception of prayer and consideration of joint arthroplasty

OBJECTIVE To compare elderly African American and white patients with osteoarthritis of the knee or hip with respect to their perceptions of the efficacy of traditional and complementary treatments and their self-care practices. METHODS An observational, cross-sectional study design using structured questionnaires was employed. RESULTS The sample consisted of 593 patients (44% African American and 56% white). The 2 groups were comparable with respect to age, disease severity or functional status, and comorbidities. African Americans were more likely than whites to report lower educational level and household income. African Americans were also more likely than whites to perceive various traditional and complementary care modalities as efficacious. However, they were less likely than whites to perceive joint replacement therapy as efficacious (odds ratio 0.52, 95% confidence interval 0.28-0.98). African American patients were more likely than white patients to rely on self-care measures for their arthritis. CONCLUSION African American and white patients with osteoarthritis of the knee or hip differ with respect to their perceptions of traditional and complementary treatments for arthritis and their self-care practices.

Quantitative MRI measures of cartilage predict knee replacement: a case–control study from the Osteoarthritis Initiative

PURPOSE To prospectively determine the reproducibility of quantitative magnetic resonance (MR) imaging biomarkers of the morphology and composition (spin lattice relaxation time in rotating frame [T1-ρ], T2) of knee cartilage in a multicenter multivendor trial involving patients with osteoarthritis (OA) and asymptomatic control subjects. MATERIALS AND METHODS This study was HIPAA compliant and approved by the institutional review committees of the participating sites, with written informed consent obtained from all participants. Fifty subjects from five sites who were deemed to have normal knee joints (n = 18), mild OA (n = 16), or moderate OA (n = 16) on the basis of Kellgren-Lawrence scores were enrolled. Each participant underwent four sequential 3-T knee MR imaging examinations with use of the same imager and with 2-63 days (median, 18 days) separating the first and last examinations. Water-excited three-dimensional T1-weighted gradient-echo imaging, T1-ρ imaging, and T2 mapping of cartilage in the axial and coronal planes were performed. Biomarker reproducibility was determined by using intraclass correlation coefficients (ICCs) and root-mean-square coefficients of variation (RMS CVs, expressed as percentages). RESULTS Morphometric biomarkers had high reproducibility, with ICCs of 0.989 or greater and RMS CVs lower than 4%. The largest differences between the healthy subjects and the patients with radiographically detected knee OA were those in T1-ρ values, but precision errors were relatively large. Reproducibility of T1-ρ values was higher in the thicker patellar cartilage (ICC range, 0.86-0.93; RMS CV range, 14%-18%) than in the femorotibial joints (ICC range, 0.20-0.84; RMS CV range, 7%-19%). Good to high reproducibility of T2 was observed, with ICCs ranging from 0.61 to 0.98 and RMS CVs ranging from 4% to 14%. CONCLUSION MR imaging measurements of cartilage morphology, T2, and patellar T1-ρ demonstrated moderate to excellent reproducibility in a clinical trial network.

Assessing physical activity in persons with knee osteoarthritis using accelerometers: data from the osteoarthritis initiative.

Context. Ethnic differences in utilization of arthroplasty may reflect differences in health-related attitudes and beliefs. Objective. To examine ethnic differences in the perception and use of prayer in the treatment of arthritis and its role in patients’ decision making toward surgery. Design. A cross-sectional survey. Setting. VA Primary Care Clinics. Patients. Patients older than 50 years with chronic moderate-to-severe knee pain, hip pain, or both. Measures. The “helpfulness of prayer” in the treatment of arthritis and patients’ attitude toward joint arthroplasty. Results. Five hundred ninety-six veterans; 44% black patients, 56% white patients. Groups were comparable with respect to age (65 ± 9.5 vs. 66 ± 9), disease severity as assessed by WOMAC (47 ± 17 vs. 45 ± 17). Black patients scored higher than white patients on the religiosity scale (77 ± 17 vs. 70 ± 21). In multivariate analysis, black patients were more likely than white patients to perceive prayer as helpful in the management of their arthritis (OR, 2.1; 95% CI, 1.19, 3.72). Black patients were also less likely than white patients to consider surgery for severe hip/knee pain (OR, 0.58; 95% CI 0.34, 0.99); this relationship between ethnicity and consideration of surgery is mediated by perceptions of “helpfulness of prayer.” The odds ratio for this relationship changes to 0.70 (P = 0.215). Conclusion. In this sample, black patients were more likely than white patients to perceive prayer as helpful and to have actually used prayer for their arthritis. Perception of helpfulness of prayer may be an important explanatory variable in the relationship between ethnicity and patients’ decision in considering arthroplasty.