Anca D. Dragomir

Lifetime risk of symptomatic knee osteoarthritis

OBJECTIVE To estimate the lifetime risk of symptomatic knee osteoarthritis (OA), overall and stratified by sex, race, education, history of knee injury, and body mass index (BMI). METHODS The lifetime risk of symptomatic OA in at least 1 knee was estimated from logistic regression models with generalized estimating equations among 3,068 participants of the Johnston County Osteoarthritis Project, a longitudinal study of black and white women and men age >or=45 years living in rural North Carolina. Radiographic, sociodemographic, and symptomatic knee data measured at baseline (1990-1997) and first followup (1999-2003) were analyzed. RESULTS The lifetime risk of symptomatic knee OA was 44.7% (95% confidence interval [95% CI] 40.0-49.3%). Cohort members with history of a knee injury had a lifetime risk of 56.8% (95% CI 48.4-65.2%). Lifetime risk rose with increasing BMI, with a risk of 2 in 3 among those who were obese. CONCLUSION Nearly half of the adults in Johnston County will develop symptomatic knee OA by age 85 years, with lifetime risk highest among obese persons. These current high risks in Johnston County may suggest similar risks in the general US population, especially given the increase in 2 major risk factors for knee OA, aging, and obesity. This underscores the immediate need for greater use of clinical and public health interventions, especially those that address weight loss and self-management, to reduce the impact of having knee OA.

Prevalence of Hip Symptoms and Radiographic and Symptomatic Hip Osteoarthritis in African Americans and Caucasians: The Johnston County Osteoarthritis Project

Objective. To report contemporary estimates of the prevalence of hip-related osteoarthritis (OA) outcomes in African Americans and Caucasians aged ≥ 45 years. Methods. Weighted prevalence estimates and their corresponding 95% confidence intervals for hip symptoms, radiographic hip OA, symptomatic hip OA, and severe radiographic hip OA were calculated using SUDAAN® for age, race, and sex subgroups among 3068 participants (33% African Americans, 38% men) in the baseline examination (1991–97) of The Johnston County Osteoarthritis Project, a population-based study of OA in North Carolina. Radiographic hip OA was defined as Kellgren-Lawrence radiographic grade ≥ 2, moderate/severe radiographic hip OA as grades 3 and 4, and symptomatic hip OA as hip symptoms in a hip with radiographic OA. Results. Hip symptoms were present in 36%; 28% had radiographic hip OA; nearly 10% had symptomatic hip OA; and 2.5% had moderate/severe radiographic hip OA. Prevalence of all 4 outcomes was higher in older individuals; most outcomes were higher for women and African Americans. Conclusion. African Americans in this population do not have a lower prevalence of hip-related OA outcomes as previous studies suggested. Increasing public and health system awareness of the relatively high prevalence of these outcomes, which can be disabling, may help to decrease their effects and ultimately prevent them.

Serum cartilage oligomeric matrix protein reflects osteoarthritis presence and severity: The Johnston county osteoarthritis project

OBJECTIVE To characterize serum cartilage oligomeric matrix protein (COMP) levels by age and gender for a radiographically defined population free of hip and knee osteoarthritis (OA), and to examine the potential utility of COMP as a diagnostic biomarker for knee OA. METHODS Serum samples and knee and hip radiographs were obtained at a baseline evaluation as part of the Johnston County Osteoarthritis Project, a population-based study of OA in rural North Carolina. A total of 291 Caucasian participants were randomly selected for COMP analysis, 143 patients with radiographic knee OA (Kellgren/Lawrence [K/L] grade > or = 2) and 148 controls with neither hip nor knee OA (K/L grade 0), evenly distributed by age and gender. COMP was quantified by competitive enzyme-linked immunosorbent assay with monoclonal antibody 17-C10. The natural log-transformed COMP data were analyzed using general linear models. RESULTS Serum COMP levels were significantly elevated (P = 0.0001) in the age > or = 65 group (mean +/- SD 1,302.1 +/- 496.7 ng/ml) versus the age 45-54 and age 55-64 groups (1,058.1 +/- 432.4 and 1,038.6 +/- 313.3, respectively). Serum COMP levels of the OA group were significantly higher than those of the control group (1,208.57 +/- 487.47 ng/ml versus 1,061.83 +/- 370.58 ng/ml; P = 0.0093). Serum COMP levels also increased significantly with knee OA K/L grade (P = 0.0047), knee OA laterality (P = 0.0043), and number of knee and hip joints involved (P = 0.0001). There was no significant difference in serum COMP levels by gender or obesity. CONCLUSION We demonstrate that in a population-based sample, serum COMP levels can distinguish an OA-affected subgroup from an unaffected subgroup and can reflect disease severity and multiple joint involvement in OA.

Self-reported functional status in osteoarthritis of the knee in a rural southern community : The role of sociodemographic factors, obesity, and knee pain

OBJECTIVE This study examined the roles of sociodemographic factors (age, race, gender, education, marital status), obesity, and severity of radiographic knee osteoarthritis (OA) and knee pain on self-reported functional status. METHODS The sample included 1,272 African-American and Caucasian individuals, aged 45 years or older, from the Johnston County Osteoarthritis Project. Analysis of variance was used to assess variation in mean Health Assessment Questionnaire (HAQ) scores by the above variables. RESULTS Mean HAQ scores differed by severity of radiographic knee OA and knee pain, obesity, and all demographic factors (P < 0.0001), except race. Only age, female sex, obesity, and knee pain severity were independent effects (P < 0.0009). Disability associated with knee pain varied by both radiographic knee OA severity and obesity. CONCLUSIONS Knee pain severity was more important than radiographic knee OA severity in determining disability. Obesity was independently associated with disability and compounded disability from knee pain. Studies of disability in knee OA should include assessment of obesity, severity of radiographic knee OA, and severity of knee pain, as well as their interactions.

Potential Risk Factors Associated With Subtypes of Uterine Leiomyomata

Objective: To compare potential risk factors for uterine leiomyomata (UL) subtypes among premenopausal African American and Caucasian women. Methods: This cross-sectional study included 986 premenopausal women, aged 35 to 49 years old, from the National Institute of Environmental Health Sciences (NIEHS) Uterine Fibroid Study (UFS). Uterine leiomyomata were subtyped as submucosal, intramural/subserosal, and diffuse, based on ultrasound examinations. Results: For both ethnic groups, age, age at menarche, body mass index, and current physical activity had similar associations across the 3 UL subtypes. Inverse associations with pregnancies after age 24 appeared to be stronger for the submucosal subtype. Current smoking was associated only with diffuse UL (adjusted odds ratio [aOR] = 1.97, 95% CI: 1.11, 3.51 in African Americans, aOR = 3.00, 95% CI: 1.07, 8.38 in Caucasians). Conclusions: Although the 2 focal UL subtypes had similar risk factor profiles, the diffuse UL subtype appeared to have a distinctive risk profile with regard to current smoking. Further study of the diffuse heterogeneity seen with uterine ultrasound is needed.

Uterine leiomyomata associated with self-reported stress urinary incontinence.

AIMS To investigate the association between the presence and characteristics of uterine leiomyomata (UL) and self-reported stress urinary incontinence (SUI). METHODS The study included 836 premenopausal participants (474 African American and 362 Caucasian) in the National Institute of Environmental Health Sciences (NIEHS) Uterine Fibroid Study. UL were characterized at baseline with ultrasound screening, and SUI was assessed at follow-up (after 4 years, on average). Linear risk models were used to estimate adjusted prevalence differences (aPD) and 95% confidence intervals (CI), controlling for age, ethnicity, body mass index (BMI), and number of deliveries. RESULTS Compared with women without UL, SUI prevalence was higher among women with any UL (aPD = 7.4%, 95% CI 0.4-14.3) and women with UL 2-4 cm (aPD = 9.6%, 95% CI 1.3-17.9). Marginally significant results were found for the presence of UL > or =4 cm and anterior UL > or =2 cm. CONCLUSIONS The observed 7% increase in prevalence of this common condition for women with UL is of clinical importance. Further research is needed before concluding that treatment for larger UL might enhance SUI treatment in some women.

A geographic assessment of health-care coverage in two "rural" north carolina communities'

The study shows the value of using basic geographic techniques to examine two key concepts of health-care delivery—service coverage and location of a community along a rural-urban continuum. Three types of coverage are discussed for two small North Carolina communities: the availability of physicians of all types, the accessibility to hospitals of all sizes, and the utilization of primary-care physicians. The usefulness of the concept of a rural-urban continuum in helping to define degree of rurality and how this concept affects coverage is demonstrated by looking at two towns midway along the continuum. Although the towns are only nine miles apart, they have very different coverage profiles, indicating that unique local health-care-delivery situations must be taken into account. The study towns do not fit the rural stereotype of poor availability and accessibility, although these two types of coverage could be improved. The micro-scale study of the utilization of primary care physicians revealed that several sociodemographic factors were not important, but that measuring perceived travel time, whether or not people had to be driven to care, perceived health status, and health insurance status were important.