Looking back on 30+ years of the Johnston County Osteoarthritis Project while looking forward with the Johnston County Health Study: A narrative review.

Over the last 30 years, knowledge of the epidemiology of osteoarthritis (OA) has dramatically advanced, and Osteoarthritis and Cartilage has been on the forefront of disseminating research findings from large OA cohort studies, including the Johnston County OA Project (JoCoOA). The JoCoOA is a population-based, prospective longitudinal cohort that began roughly 30 years ago with a key focus on understanding prevalence, incidence, and progression of OA, as well as its risk factors, in a predominantly rural population of Black and White adults 45+ years old in a county in the southeastern United States. Selected OA results that will be discussed in this review include racial differences, lifetime risk, biomarkers, mortality, and OA risk factors.

Association of Traumatic Knee Injury With Radiographic Evidence of Knee Osteoarthritis in Military Officers.

Objective: The association between knee injury and knee osteoarthritis (OA) is understudied relative to its importance, particularly in younger populations. This study was undertaken to examine the association of knee injury with radiographic features of knee OA in military officers, who have a physically demanding profession and high rates of knee injury.

Methods: Participants were recruited in 2015-2017 from an existing program that enrolled 6,452 military officers during 2004-2009.

Effect of Diet and Exercise on Knee Pain in Patients With Osteoarthritis and Overweight or Obesity: A Randomized Clinical Trial.

Importance: Some weight loss and exercise programs that have been successful in academic center-based trials have not been evaluated in community settings.

Objective: To determine whether adaptation of a diet and exercise intervention to community settings resulted in a statistically significant reduction in pain, compared with an attention control group, at 18-month follow-up.

Design, Setting, And Participants: Assessor-blinded randomized clinical trial conducted in community settings in urban and rural counties in North Carolina.

Point prevalence of Hip Symptoms, Radiographic, And Symptomatic OA at Five Time Points: The Johnston County Osteoarthritis Project, 1991-2018.

Objective: To describe the point prevalence of hip symptoms, radiographic hip osteoarthritis (rHOA), severe rHOA, and symptomatic rHOA (sxHOA) at five time points in the longitudinal, population-based Johnston County Osteoarthritis Project (JoCoOA).

Design: Data were from 3068 JoCoOA participants who attended up to five study visits (1991-2018). Standardized supine pelvis radiographs were read by a single, expert musculoskeletal radiologist with high reliability.

Tibiofemoral knee osteoarthritis progresses symmetrically by knee compartment in the GOGO cohort.

Objective: To evaluate the degree of symmetry of knee osteoarthritis (OA) structural severity and progression of participants with a mean follow-up time of 3.8 years.

Design: Participants from the Genetics of Generalized Osteoarthritis (GOGO) study (n = 705) were selected on the basis of radiographic evidence of OA in at least 1 knee, availability of radiographs at baseline and follow-up, and no history of prior knee injury or surgery.

Association of Biomarkers with Individual and Multiple Body Sites of Pain: The Johnston County Osteoarthritis Project.

Introduction: Biochemical biomarkers may provide insight into musculoskeletal pain reported at individual or multiple body sites. The purpose of this study was to determine if biomarkers or pressure-pain threshold (PPT) were associated with individual or multiple sites of pain.

Methods: This cross-sectional analysis included 689 community-based participants.

Biomarker clusters differentiate phenotypes of lumbar spine degeneration and low back pain: The Johnston County Osteoarthritis Project.

Objective: Describe the association between biomarkers and lumbar spine degeneration (vertebral osteophytes [OST], facet joint osteoarthritis [FOA], and disc space narrowing [DSN]), for persons with and without low back pain (LBP) and determine whether clusters based on biomarkers differentiate lumbar spine structure with and without LBP.

Methods: Using data from the Johnston County Osteoarthritis Project (2006-2010), we measured serum N-cadherin, Keratin-19, Lumican, CXCL6, RANTES, HA, IL-6, BDNF, OPG, and NPY, and urinary CTX-II. Biomarkers were used to group participants using k-means cluster analysis.

Reinvigorating an Academy of Medical Educators Using Ecological Systems Theory.

The educational framework of communities of practice postulates that early learners join medical communities as social networks that provide a common identity, role modeling and mentorship, and experiential learning. While being elected into a medical society is an honor, member engagement in these groups can falter if the society membership is seen as an honorific rather than one requiring continuing participation. As an example, Academies of Medical Educators have been established by many academic medical centers to encourage collaboration, skill development, professional identity formation, and scholarship.

Association of Increased Serum Lipopolysaccharide, But Not Microbial Dysbiosis, With Obesity-Related Osteoarthritis.

Objective: To test the hypothesis that an altered gut microbiota (dysbiosis) plays a role in obesity-associated osteoarthritis (OA).

Methods: Stool and blood samples were collected from 92 participants with a body mass index (BMI) ≥30 kg/m , recruited from the Johnston County Osteoarthritis Project. OA patients (n = 50) had hand and knee OA (Kellgren/Lawrence [K/L] grade ≥2 or arthroplasty).

The Prevalence of Knee Symptoms, Radiographic, and Symptomatic Osteoarthritis at Four Time Points: The Johnston County Osteoarthritis Project, 1999-2018.

Objective: To describe point prevalence of knee symptoms, radiographic knee osteoarthritis (rKOA), severe rKOA, and symptomatic rKOA at four time points in the longitudinal, population-based Johnston County Osteoarthritis Project (JoCo OA).

Methods: Data were from 2573 JoCo OA participants with up to 18 years of follow-up (1999-2018) and standardized fixed-flexion knee radiographs read by a single, reliable expert musculoskeletal radiologist. The four outcomes were 1) self-reported knee symptoms, defined by "On most days, do you have pain, aching, or stiffness in your right/left knee?"; 2) rKOA, defined as a Kellgren-Lawrence grade (KLG) of 2 to 4); 3) severe rKOA, defined as a KLG of 3 or 4; and 4) symptomatic rKOA, defined as both symptoms and rKOA in the same joint.

Associations Between Baseline and Longitudinal Semiautomated Quantitative Joint Space Width at the Hip and Incident Hip Osteoarthritis: Data From a Community-Based Cohort.

Objective: To evaluate quantitative joint space width (JSW) at 10-, 30-, and 50-degree locations in relation to incident radiographic and symptomatic hip osteoarthritis (HOA) in a community-based cohort.

Methods: Data were from Johnston County OA Project participants with supine hip radiographs at each of 4 time points; all had Kellgren/Lawrence (K/L) grades and quantitative JSW. We assessed covariates (age, race, height, weight, body mass index [BMI]) associated with quantitative JSW and hip-level associations between quantitative JSW and HOA over time using sex-stratified and multivariable-adjusted linear mixed models.

Predictors of Lumbar Spine Degeneration and Low Back Pain in the Community: The Johnston County Osteoarthritis Project.

Objective: To determine the incidence and worsening of lumbar spine structure and low back pain (LBP) and whether they are predicted by demographic characteristics or clinical characteristics or appendicular joint osteoarthritis (OA).

Methods: Paired baseline (2003-2004) and follow-up (2006-2010) lumbar spine radiographs from the Johnston County Osteoarthritis Project were graded for osteophytes (OST), disc space narrowing (DSN), spondylolisthesis, and presence of facet joint OA (FOA). Spine OA was defined as at least mild OST and mild DSN at the same level for any level of the lumbar spine.

Discovery and fine-mapping of height loci via high-density imputation of GWASs in individuals of African ancestry.

Although many loci have been associated with height in European ancestry populations, very few have been identified in African ancestry individuals. Furthermore, many of the known loci have yet to be generalized to and fine-mapped within a large-scale African ancestry sample. We performed sex-combined and sex-stratified meta-analyses in up to 52,764 individuals with height and genome-wide genotyping data from the African Ancestry Anthropometry Genetics Consortium (AAAGC).

Knee osteoarthritis and time-to all-cause mortality in six community-based cohorts: an international meta-analysis of individual participant-level data.

Background: Osteoarthritis (OA) is a chronic joint disease, with increasing global burden of disability and healthcare utilisation. Recent meta-analyses have shown a range of effects of OA on mortality, reflecting different OA definitions and study methods. We seek to overcome limitations introduced when using aggregate results by gathering individual participant-level data (IPD) from international observational studies and standardising methods to determine the association of knee OA with mortality in the general population.

A Meta-Analysis of the Transferability of Bone Mineral Density Genetic Loci Associations From European to African Ancestry Populations.

Genetic studies of bone mineral density (BMD) largely have been conducted in European populations. We therefore conducted a meta-analysis of six independent African ancestry cohorts to determine whether previously reported BMD loci identified in European populations were transferable to African ancestry populations. We included nearly 5000 individuals with both genetic data and assessments of BMD.

Foot Osteoarthritis Frequency and Associated Factors in a Community-Based Cross-Sectional Study of White and African American Adults.

Objective: Few studies have explored foot osteoarthritis (OA) in the general population. The purpose of this study was to determine the frequency of foot OA and identify associated factors in a cross-sectional analysis of a large community-based cohort.

Methods: Data were from the 2013-2015 study visit of the Johnston County OA Project.

Identification of Sarcopenia Components That Discriminate Slow Walking Speed: A Pooled Data Analysis.

Background: The Sarcopenia Definitions and Outcomes Consortium (SDOC) sought to identify cut points for muscle strength and body composition measures derived from dual-energy x-ray absorptiometry (DXA) that discriminate older adults with slow walking speed. This article presents the core analyses used to guide the SDOC position statements.

Design: Cross-sectional data analyses of pooled data.

Associations among neighborhood poverty, perceived neighborhood environment, and depressed mood are mediated by physical activity, perceived individual control, and loneliness.

Few studies have documented the pathways through which individual level variables mediate the effects of neighborhoods on health. This study used structural equation modeling to examine if neighborhood characteristics are associated with depressive symptoms, and if so, what factors mediated these relationships. Cross-sectional data came from a sample of mostly rural, older adults in North Carolina (n = 1,558).

Is the Association between Knee Injury and Knee Osteoarthritis Modified by the Presence of General Joint Hypermobility.

Objective: To evaluate whether joint hypermobility modifies the association between knee joint injury and knee osteoarthritis (OA) among adults.

Methods: Data were from three studies: Genetics of Generalized Osteoarthritis (GOGO; N=2,341), Genetics of Osteoarthritis (GO; N=1,872), and the population-based Johnston County Osteoarthritis Project (JoCoOA; N=1,937). Knee injury was defined as a self-report of prior fracture or severe injury to either knee.

Author Correction: Genome-wide association study of knee pain identifies associations with GDF5 and COL27A1 in UK Biobank.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Genome-wide meta-analysis identified novel variant associated with hallux valgus in Caucasians.

Background: Hallux valgus, one of the most common structural foot deformities, is highly heritable. However, previous efforts to elucidate the genetic underpinnings of hallux valgus through a genome-wide association study (GWAS) conducted in 4409 Caucasians did not identify genome-wide significant associations with hallux valgus in both gender-specific and sex-combined GWAS meta-analyses. In this analysis, we add newly available data and more densely imputed genotypes to identify novel genetic variants associated with hallux valgus.

Effects of Comorbid Cardiovascular Disease and Diabetes on Hand Osteoarthritis, Pain, and Functional State Transitions: The Johnston County Osteoarthritis Project.

Objective: The purpose of this study is to examine the course of hand osteoarthritis (HOA) and its relationship with cardiovascular disease (CVD) and diabetes (DM).

Methods: Data were collected at 3 timepoints from 845 Johnston County Osteoarthritis Project participants (two-thirds women, one-third African Americans, mean age 60 yrs) with and without HOA, CVD, or DM. A diagnosis of radiographic HOA (rHOA) required a Kellgren-Lawrence severity grade of ≥ 2 in at least 3 joints in each hand.

Comorbid conditions and the transition among states of hip osteoarthritis and symptoms in a community-based study: a multi-state time-to-event model approach.

Background: We examined the association of three common chronic conditions (obesity, diabetes mellitus [DM], and cardiovascular disease [CVD]) with transitions among states of hip osteoarthritis (HOA).

Methods: This longitudinal analysis used data from the Johnston County Osteoarthritis Project (JoCo OA, n = 3857), a community-based study in North Carolina, USA, with 18.4 ± 1.