Individual risk factors for hip osteoarthritis: obesity, hip injury, and physical activity

Musculoskeletal function following bariatric surgery

OBJECTIVE

Bariatric surgery is an effective method for acute weight loss. While the impact of bariatric surgery on general medical conditions (e.g., type 2 diabetes) is well documented, few studies focus on physical functional outcomes following weight-loss induced by bariatric surgery.

DESIGN AND METHODS

We report on 50 women aged 20-74 scheduled for Roux-en-Y gastric bypass (RYGB) procedure who were enrolled for a prospective 1-year study. Height, weight, and waist circumference were recorded preoperatively and at 6 and 12 months, postoperatively. To track musculoskeletal/physical function changes, the timed-get-up-and-go (TGUG) and short-form health survey-36 (SF-36) and short musculoskeletal function assessment (SFMA) questionnaires were administered.

RESULTS

Patients had significant weight loss and functional improvement. At 1 year mean weight loss was 48.5 kg and mean TGUG improvement was 3.1 s. SMFA and SF-36 also showed improvement in functional components with weight loss at 6 months and 1-year post surgery. Significant associations were observed between TGUG and SMFA measures at all time points. Final weight at 1 year post bariatric surgery was also significantly correlated with most functional outcomes and changes in these outcomes. Partial correlations controlling for age revealed additional associations between body weight and functional outcomes, especially at the 6-month visit.

CONCLUSION

Our results suggest that significant rapid weight loss, such as that attained by bariatric surgery, acutely improves musculoskeletal function in morbidly obese patients. Additionally, for patients with musculoskeletal disease or injury, weight loss resulting from bariatric surgery may serve as an adjunct for improving global functional outcome, and enhancing the rehabilitation potential.

Primary osteoarthritis of the hip: a genetic disease caused by European genetic variants

Primary osteoarthritis of the hip is a separate phenotype that occurs at a rate of 3% to 6% in the populations of the world with European ancestry. In all non-European populations, there is a consistent rarity of primary osteoarthritis that suggests a different etiology for these few patients. Family, sibling, and twin studies prove primary osteoarthritis to be a genetic disease with a 50% heritability caused by European genetic variants. The genetic basis is reinforced by the lower rate of primary osteoarthritis in American minorities consistent with their degree of European gene admixture. Whether the mechanism of degeneration of primary osteoarthritis may be secondary through a morphologic deformity, such as femoroacetabular impingement, remains unknown. The virtual absence of the disease in non-Europeans indicates that the European gene component is necessary for the expression of this separate phenotype of osteoarthritis.

Exemestane for breast cancer prevention: a critical shift?

The Mammary Prevention 3 (MAP.3) placebo-controlled randomized trial in 4,560 high-risk postmenopausal women showed a 65% reduction in invasive breast cancer with the use of exemestane at 35 months median follow-up. Few differences in adverse events were observed between the arms, suggesting a promising risk:benefit balance with exemestane for use in chemoprevention. Yet, the MAP.3 design and implementation raise concerns regarding limited data maturity and not prospectively including key bone-related and other toxicities as study end points. Exemestane for prevention is juxtaposed against selective estrogen receptor modulators and the other aromatase inhibitors. Additional issues for prevention, including the influence of obesity, alternative dosing, and biomarker use in phase III trials, are addressed.

SIGNIFICANCE

The recently completed MAP.3 trial of exemestane for breast cancer prevention offers a potential new standard for pharmaceutical risk reduction in high-risk postmenopausal women. In addition to describing key findings from the publication of MAP.3 and related trials, our review undertakes a detailed analysis of the strengths and weaknesses of MAP.3 as well as the implications for future prevention research.

Impact of obesity and diabetes on arthritis: An update

The incidence of obesity and diabetes has been increased with alarming rate in recent years and became a common problem around the globe including developing as well as in developed countries with incalculable social costs. Obesity and type 2 diabetes are two common co-morbidities occur together. Obesity and diabetes is closely associated with many diseases, osteoarthritis, hypertension, certain form of cancer, sleep-breathing disorders and coronary heart disease. Impacts of obesity and diabetes (insulin resistance) on arthritis have been seen in patients that we associated with combination of various factors like increased availability of high- energy foods, genetic susceptibility and decreased physical activity in modern society. Arthritis is becoming pandemic around the globe and its occurrence with obesity and diabetes has been observed more common than ever. Combination of these two chronic conditions makes these diseases more vulnerable for human health. Till now very limited information is established about the pathological and mechanistic correlation among these health ailments. In this review article we aimed to survey the literature covering the influence of obesity and diabetes on arthritis pathology and tried to establish correlation with these diseases.

The clinical pattern of knee osteoarthritis in Jordan: a hospital based study

BACKGROUND

Different clinical profiles of knee osteoarthritis (KOA) have been reported in the literature. The aim of this investigation was to describe the clinical patterns of KOA in an ethnically distinct and homogenous population that has not been widely reported. Patients with KOA were seen in outpatient rehabilitation and orthopedic clinic of Jordan University Hospital (JUH), to determine any possible association between age, BMI, radiographic severity, and pain severity.

METHODS

Patients diagnosed with KOA attending an outpatient rehabilitation clinic at JUH were studied to describe their clinical characteristics. They were included based on criteria developed by the American College of Rheumatology. Detailed histories, clinical examinations and X-rays, and anthropometric data were obtained. Data analysis focused on descriptive statistics and correlations among demographic and clinical characteristics.

RESULTS

The study included 214 patients with a mean age of 55.3 years (range = 30-84 years). The mean BMI was 29.5± 5.6. We found a significant moderate positive correlation between age and radiographic severity of KOA (0.435; p <. 001) and pain severity (0.383; p. <. 001). There was also a significant weak positive correlation between BMI, radiographic severity of KOA (0.242, p <. 05), and pain severity (0.266, p. <. 01).

CONCLUSIONS

We concluded that in this hospital-based cohort study in Jordan, the clinical pattern of KOA is comparable to Western cultures. However, the combination of BMI and mechanical loading during everyday activities that include different religious and cultural habits and may help explain the high level of radiographic severity in our sample.

Arthroplasty Utilization in the United States is Predicted by Age-Specific Population Groups

Osteoarthritis is a common indication for hip and knee arthroplasty. An accurate assessment of current trends in healthcare utilization as they relate to arthroplasty may predict the needs of a growing elderly population in the United States. First, incidence data was queried from the United States Nationwide Inpatient Sample from 1993 to 2009. Patients undergoing total knee and hip arthroplasty were identified. Then, the United States Census Bureau was queried for population data from the same study period as well as to provide future projections. Arthroplasty followed linear regression models with the population group >64 years in both hip and knee groups. Projections for procedure incidence in the year 2050 based on these models were calculated to be 1,859,553 cases (hip) and 4,174,554 cases (knee). The need for hip and knee arthroplasty is expected to grow significantly in the upcoming years, given population growth predictions.

Does endotoxaemia contribute to osteoarthritis in obese patients?

OA (osteoarthritis) is a degenerative condition associated with obesity. A number of metabolic explanations have been proposed to explain the association between obesity and OA in non-weight-bearing joints; however, none of these hypotheses have been demonstrated empirically. In the present Hypothesis article, we recognize that obesity is associated with compromised gut mucosa, translocation of microbiota and raised serum LPS (lipopolysaccharide). The consequent activation of the innate immune response leads to increased serum titres of inflammatory mediators in obese patients, with both local and systemic markers of inflammation associated with onset and progression of OA. Furthermore, a number of workers have shown that articular cartilage repair is impaired by a range of inflammatory mediators, both in vitro and in vivo. We propose that metabolic endotoxaemia, caused by impaired gastric mucosa and low-grade chronic inflammation, may contribute to the onset and progression of OA in obese patients. This may account for the association between obesity and OA at non-weight-bearing joints which cannot be explained by biomechanical factors.

Is lifelong knee joint force from work, home, and sport related to knee osteoarthritis?

Purpose. To investigate the association of cumulative lifetime knee joint force on the risk of self-reported medically-diagnosed knee osteoarthritis (OA). Methods. Exposure data on lifetime physical activity type (occupational, household, sport/recreation) and dose (frequency, intensity, duration) were collected from 4,269 Canadian men and women as part of the Physical Activity and Joint Heath cohort study. Subjects were ranked in terms of the "cumulative peak force index", a measure of lifetime mechanical knee force. Multivariable logistic regression was conducted to obtain adjusted effects for mean lifetime knee force on the risk of knee OA. Results. High levels of total lifetime, occupational and household-related force were associated with an increased in risk of OA, with odds ratio's ranging from approximately 1.3 to 2. Joint injury, high BMI and older age were related to risk of knee OA, consistent with previous studies. Conclusions. A newly developed measure of lifetime mechanical knee force from physical activity was employed to estimate the risk of self-reported, medically-diagnosed knee OA. While there are limitations, this paper suggests that high levels of total lifetime force (all domains combined), and occupational force in men and household force in women were risk factors for knee OA.

Musculoskeletal pain in patients with type 2 diabetes

AIMS

The aims were to investigate the prevalence of musculoskeletal pain in patients with type 2 diabetes and demonstrate possible associated factors.

METHODS

Nine hundred fifty-one patients completed a validated questionnaire used in The Danish Health and Morbidity Survey and results were compared to data for 2923 matched subjects from the Danish population. Musculoskeletal pain was self-reported Pain in the shoulder and neck; Low-back pain; and Pain in the arm, hand, knee and/or hip.

RESULTS

Compared to the age, gender and region matched controls patients reported musculoskeletal pain 1.7-2.1 times as frequent (p<0.001). Pain was more frequently reported in women (p<0.001). Low-back pain and Pain in the arm, hand, knee and/or hip was associated with body mass index (p<0.005). Low-back pain was associated with a sedentary life style, impaired quality of life and reduced physical function (p<0.05).

CONCLUSIONS

The prevalence of musculoskeletal pain was seriously increased in patients with type 2 diabetes. It was associated with body mass index, reduced quality of life, low physical function and the ability to be physical active. Focus on musculoskeletal pain in clinical practice is therefore of major importance in lifestyle interventions in type 2 diabetes.

The osteoarthritic niche and modulation of skeletal stem cell function for regenerative medicine

Osteoarthritis (OA) is the most common cause of arthritis worldwide and represents a significant healthcare burden, particularly in the context of an ageing population. Traditionally, painkillers, injections and physiotherapy have been the mainstay of treatment, with patients being referred for joint replacement surgery (arthroplasty) when these options fail. Whilst effective in reducing pain and improving joint function, these approaches are not without potential complications. With the development of tissue-engineering techniques over recent years there has been considerable interest in applying these strategies to provide new, innovative, alternative effective means of treating OA. This review explores the unique microenvironment present within an osteoarthritic joint, highlighting the features that comprise the osteoarthritic niche and could be modulated in the development of novel treatments for OA. Existing tissue-engineering strategies for repairing bone and cartilage defects are discussed, with particular reference to how these might be modified, both to improve existing treatments, such as impaction bone grafting, as well as in the development of future treatments for OA.

Relationship of acetabular dysplasia and femoroacetabular impingement to hip osteoarthritis: a focused review

Hip osteoarthritis (OA) leads to significant functional limitations and economic burden. If modifiable risk factors for hip OA are identified, it may be possible to implement preventative measures. Bony abnormalities associated with acetabular dysplasia (AD) and femoroacetabular impingement have been recently implicated as risk factors for hip OA. The purpose of this focused review is to summarize the available evidence describing the relationship between bony abnormalities and hip OA. A librarian-assisted database search with PubMed, Embase, and CENTRAL was performed. Relevant articles were identified and assessed for inclusion criteria. The authors reviewed cohort and case-control studies that reported on the association between abnormal hip morphology and hip OA. The available literature suggests that an association exists between bony abnormalities found in AD and femoroacetabular impingement and hip OA, and preliminary evidence suggests that AD is a risk factor for OA; however, these conclusions are based on limited evidence. Prospective, longitudinal studies are needed to confirm the causal relationship between abnormal hip morphology and the future development of hip OA.

Epidemiological evidence for work load as a risk factor for osteoarthritis of the hip: a systematic review

Objective

Osteoarthritis of the hip (OA) is a common degenerative disorder of the joint cartilage that presents a major public health problem worldwide. While intrinsic risk factors (e.g, body mass and morphology) have been identified, external risk factors are not well understood. In this systematic review, the evidence for workload as a risk factor for hip OA is summarized and used to derive recommendations for prevention and further research.

Methods

Epidemiological studies on workload or occupation and osteoarthritis of the hip were identified through database and bibliography searches. Using pre-defined quality criteria, 30 studies were selected for critical evaluation; six of these provided quantitative exposure data.

Results

Study results were too heterogeneous to develop pooled risk estimates by specific work activities. The weight of evidence favors a graded association between long-term exposure to heavy lifting and risk of hip OA. Long-term exposure to standing at work might also increase the risk of hip OA.

Conclusions

It is not possible to estimate a quantitative dose-response relationship between workload and hip OA using existing data, but there is enough evidence available to identify job-related heavy lifting and standing as hazards, and thus to begin developing recommendations for preventing hip OA by limiting the amount and duration of these activities. Future research to identify specific risk factors for work-related hip OA should focus on implementing rigorous study methods with quantitative exposure measures and objective diagnostic criteria.

The pathology of the end-stage osteoarthritic lesion of the knee: potential role in cartilage repair

The purpose was to explore whether there were any pathological characteristics of the end-stage osteoarthritic sclerotic lesion that have potential to participate in cartilage repair. Specimens harvested following total knee surgery were examined for gross pathology including staining with Safranin O. Multiple small sections of the lesion were placed in tissue culture for 6 weeks. Gross examination and photographic documentation was made at 3 and 6 weeks. At 6 weeks the specimens from culture were subject to histological examination. The pathology of the end-stage osteoarthritic lesion showed sclerotic bone, dead osteons, hypervascularity and scattered cartilaginous aggregates. Additional observations showed multiple pitting on the sclerotic surface, which histologically was related to three events; fragmentation of dead bone, ruptured blood vessels, and eroded aggregates. There were no pathological or biological changes in the specimens following the time in tissue culture. The in-depth pathological evaluation showed the end-stage osteoarthritic lesion to have certain features with potential to facilitate cartilage repair. The cartilaginous aggregates may be a participant in cartilage repair following surgery. The cartilaginous aggregates remained unchanged in the tissue culture absent the normal synovial joint chemical and physical environment and therefore further testing with a different experimental model would be necessary to establish these aggregates as a source of cartilage regeneration. The multiple small depressions in this lesion may have potential to be a "home" for therapeutics.

The benefits of bariatric surgery in obese patients with hip and knee osteoarthritis: a systematic review

Osteoarthritis is a common progressive disease leading to joint pain and severe disability. It is a complex multifactorial disease leading to damage of cartilage, deposition of subchondral bone matrix and release of pro-inflammatory cytokines. Obesity is an emerging epidemic and also an important risk factor for osteoarthritis. Weight loss has been shown to improve pain and function in hip and knee joints with osteoarthritis. Bariatric surgery currently is the only evidence-based approach to marked weight loss in obese individuals. However, there is currently limited literature to evaluate the role of bariatric surgery in hip and knee osteoarthritis. The objective of the present study was to systematically review the literature regarding the effectiveness of bariatric surgery in obese adult patients in improving large weight-bearing joint (hip and knee) osteoarthritis. Published English-language manuscripts were considered for review inclusion. A comprehensive search of electronic databases using broad search terms was completed. From a total of 400 articles, eight articles were identified. A total of six studies were included for qualitative analysis. A general trend was identified indicating improved hip and knee osteoarthritis following marked weight loss secondary to bariatric surgery. This systematic review demonstrates that bariatric surgery may benefit obese patients with hip or knee osteoarthritis. However, this review identifies the need for randomized controlled trials to clarify the role and indications for bariatric surgery.

Chiropractic care of a 70-year-old female patient with hip osteoarthritis

OBJECTIVE

The purpose of this case report is to describe the response to chiropractic care of a geriatric patient with left hip pain, a history of repetitive falls, poor balance, myofascial dysfunction, and hip osteoarthritis.

CLINICAL FEATURES

A 70-year-old, white, female patient presented for chiropractic care with a chief complaint of left hip pain of 1 year's duration and a history of 2 falls within the past 5 years. The patient's initial Lower Extremity Functional Index score was 42%. Important initial examination findings include a body mass index of 45.0, a One Leg Standing Test of 4 seconds, a Timed Up and Go test of 17 seconds, decreased active range of motion findings, and degenerative radiological findings of the left hip joint.

INTERVENTION AND OUTCOME

Chiropractic treatment primarily consisted of hip and spinal manipulation, mobilization, and passive stretching. The patient was seen 16 times over a 12-week period. After 12 weeks of care, the patient had a significant decrease on the Lower Extremity Functional Index and had demonstrated improvements in left hip internal rotation and in Timed Up and Go and One Leg Standing Test times. The Patient Global Impression of Change scale indicated that the patient was "very much better."

CONCLUSION

This case illustrates a patient who had increased range of motion, improved balance and gait speed, and decreased disability after a 12-week course of chiropractic care.

Quantification of the whole-body burden of radiographic osteoarthritis using factor analysis

Introduction

Although osteoarthritis (OA) commonly involves multiple joints, no widely accepted method for quantifying whole-body OA burden exists. Therefore, our aim was to apply factor analytic methods to radiographic OA (rOA) grades across multiple joint sites, representing both presence and severity, to quantify the burden of rOA.

Methods

We used cross-sectional data from the Johnston County Osteoarthritis Project. The sample (n = 2092) had a mean age of 65 ± 11 years, body mass index (BMI) 31 ± 7 kg/m², with 33% men and 34% African Americans. A single expert reader (intra-rater κ = 0.89) provided radiographic grades based on standard atlases for the hands (30 joints, including bilateral distal and proximal interphalangeal [IP], thumb IP, metacarpophalangeal [MCP] and carpometacarpal [CMC] joints), knees (patellofemoral and tibiofemoral, 4 joints), hips (2 joints), and spine (5 levels [L1/2 to L5/S1]). All grades were entered into an exploratory common factor analysis as continuous variables. Stratified factor analyses were used to look for differences by gender, race, age, and cohort subgroups.

Results

Four factors were identified as follows: IP/CMC factor (20 joints), MCP factor (8 joints), Knee factor (4 joints), Spine factor (5 levels). These factors had high internal consistency reliability (Cronbach's α range 0.80 to 0.95), were not collapsible into a single factor, and had moderate between-factor correlations (Pearson correlation coefficient r = 0.24 to 0.44). There were no major differences in factor structure when stratified by subgroup.

Conclusions

The 4 factors obtained in this analysis indicate that the variables contained within each factor share an underlying cause, but the 4 factors are distinct, suggesting that combining these joint sites into one overall measure is not appropriate. Using such factors to reflect multi-joint rOA in statistical models can reduce the number of variables needed and increase precision.

Hip Osteoarthritis MRI Scoring System (HOAMS): reliability and associations with radiographic and clinical findings

OBJECTIVE

To develop a semiquantitative MRI-based scoring system (HOAMS) of hip osteoarthritis (OA) and test its reliability and validity.

DESIGN

Fifty-two patients with chronic hip pain were included. 1.5T magnetic resonance imaging (MRI) was performed on all patients. Pelvic radiographs were scored according to the Kellgren-Lawrence (KL) system. Clinical outcomes were assessed by the hip osteoarthritis outcome score (HOOS). MRIs were analyzed using a novel whole-joint MRI score that incorporated 13 articular features. Reliability was determined on a random subset of 15 cases. Weighted-kappa statistics and overall agreement were used as a measure of intra- and inter-observer reliability. Associations between MRI features and radiographic OA severity were calculated using Cochran-Armitage test for trend. Ordinal logistic regression was used to assess associations between MRI features and severity of pain and functional limitation.

RESULTS

Distribution of radiographic grading was: KL 0=12 (27%), KL 1=11 (25%), KL 2=14 (32%), KL 3=5 (11%) and KL 4=2 (5%). Intra-reader reliability for the different features ranged from 0.18 (cysts) to 0.85 (cartilage). Inter-reader reliability ranged between 0.15 (cysts) and 0.85 (BMLs). Low kappas were due to low frequencies of some features as overall percent agreement was good to excellent (83.8% and 83.1%). There was a strong association between MRI-detected lesions and radiographic severity (P=0.002). Non-significant trends were observed between MRI features and clinical outcomes.

CONCLUSION

MRI-based semiquantitative assessment of the hip shows adequate reliability. Presence of more severe MRI-detected intraarticular pathology shows a strong association with radiographic OA. The results suggest possible associations between MRI-detected pathology and clinical symptoms.

Weight gain and the risk of total hip replacement a population-based prospective cohort study of 265,725 individuals

OBJECTIVE

To study the association between change in the body mass index (BMI) at different ages and the risk of a later total hip replacement (THR) due to primary osteoarthritis (OA).

DESIGN

A total of 265,725 individuals who had two repeated measurements of weight and height were included from national health screenings. These individuals were followed prospectively. The data were matched with the Norwegian Arthroplasty Register and 4,442 of these individuals were identified as having received a THR for primary OA. Cox proportional hazard regression was used to calculate sex-specific relative risks for having a THR according to age at screening and BMI change.

RESULTS

Men and women aged 20 years or younger at the first screening in the quartile with the greatest BMI change per year had more than twice the risk of later having a THR compared with those in the quartile with the smallest BMI change per year. For men older than 30 years at the first screening, there was no relationship between BMI gain, or weight gain, and later risk of THR. For older women, BMI gain was associated with risk of THR, but to a lesser degree than in younger women.

CONCLUSION

There was a clear relationship between change in BMI and the risk of later THR in young men and women, whereas the association was absent in older men and weaker in older women. It is important to focus on weight control to prevent future OA, and the preventive strategy should be focused on the young population.

Influence of lifetime hip joint force on the risk of self-reported hip osteoarthritis: a community-based cohort study

OBJECTIVE

To investigate the influence of cumulative lifetime hip joint force on the risk of self-reported medically-diagnosed hip osteoarthritis (OA).

DESIGN

Prospective cohort.

SETTING

General population.

PARTICIPANTS

Members of Canadian Association of Retired Persons, community-dwelling.

MAIN OUTCOME

Health-professional diagnosed hip OA, self-reported.

METHODS

Exposure data on lifetime physical activity type (occupational, household, sport) and dose (frequency, intensity, duration) was collected in 2005. Subjects were ranked in terms of a 'cumulative peak force index' (CFPI), a measure of lifetime mechanical hip joint force. Multivariable survival analyses were performed to obtain adjusted effects for mean lifetime exposure and during 5-year age periods.

RESULTS

Of 2918 subjects aged 45-85, 176 (6.03%) developed hip OA during the 2-year follow up (43 men, 133 women). The highest quintile of mean lifetime hip CPFI (HR 2.32; 95% CI 1.31-4.12), and high hip force in three age periods (35-39, 40-44, 45-49) were independently associated with hip OA. Previous hip injury was an approximate five-fold risk for development of hip OA across all models. In analysis by activity domain (occupation, sport, household), there was a trend (non-significant) for the highest quintile of occupational force, but not sport or household, to be associated with hip OA.

CONCLUSIONS

A newly proposed measure of lifetime mechanical hip force was used to estimate the risk of self-reported, medically-diagnosed hip OA. While there are important limitations, this prospective study suggests that lifelong physical activity is generally safe. Very high levels of lifetime force from all domains combined, and in particular from occupational forces, may be important in the etiology of hip OA.

Rheumatic manifestations of diabetes mellitus

DM is associated with various musculoskeletal manifestations. The strength of this relationship varies among the various musculoskeletal disorders; the associations are based mostly on epidemiologic data. For most of these conditions, definitive pathophysiologic correlates are lacking.Hand and shoulder disorders occur more frequently than other musculoskeletal manifestations of DM. Recognition of the association between DM and shoulder adhesive capsulitis, DD, and stenosing flexor tenosynovitis facilitates their correct diagnosis in the setting of DM and prompt initiation of appropriate treatment, which may include optimizing glycemic control. Conversely, awareness and identification of the characteristic musculoskeletal manifestations of DM may facilitate earlier diagnosis of DM and initiation of glucose-lowering therapy to retard the development of diabetic complications.Much less has been published about the musculoskeletal complications of DM than about its micro- and macrovascular complications. Prospective case-control cohort studies are needed to establish the true prevalence of musculoskeletal complications of DM and the metabolic syndrome, especially in this era of tighter glycemic control.The potential relationship between DM and the development of OA needs to be clarified in large, prospective, case-control cohort studies. The effect on musculoskeletal manifestations of various therapeutic regimens to manage DM should be studied prospectively. Treatment regimens for some musculoskeletal conditions associated with DM, such as DISH, should be studied in larger prospective, randomized,controlled clinical trials.At the molecular level, further studies are warranted to clarify the potential contribution of AGEs and adipokines to the development of OA and diabetic musculoskeletal syndromes, such as shoulder adhesive capsulitis, DD, stenosing flexor tenosynovitis, and LJM. Identification of such molecular targets for therapy would promote the development of additional treatments for these and other rheumatic diseases.

One in four people may develop symptomatic hip osteoarthritis in his or her lifetime

OBJECTIVE

To estimate the lifetime risk of symptomatic hip osteoarthritis (OA).

DESIGN

We analyzed data from the Johnston County Osteoarthritis Project [a longitudinal population-based study of OA in North Carolina, United States (n=3068)]. The weighted baseline sample comprised 18% blacks and 54% women, and the mean age was 63 years (range=45-93). Symptomatic hip OA was defined as a Kellgren-Lawrence (K-L) radiographic score of ≥ 2 (anterior-posterior pelvis X-rays) and pain, aching or stiffness on most days, or groin pain, in the same hip. Lifetime risk, defined as the proportion who developed symptomatic hip OA in at least one hip by age 85, among people who live to age 85, was modeled using logistic regression with repeated measures (through generalized estimating equations).

RESULTS

Lifetime risk of symptomatic hip OA was 25.3% [95% confidence interval (CI)=21.3-29.3]. Lifetime risk was similar by sex, race, highest educational attainment, and hip injury history. We studied lifetime risk by body mass index (BMI) in three forms: at age 18; at baseline and follow-up; and at age 18, baseline and follow-up and found no differences in estimates.

CONCLUSION

The burden of symptomatic hip OA is substantial with one in four people developing this condition by age 85. The similar race-specific estimates suggest that racial disparities in total hip replacements are not attributable to differences in disease occurrence. Despite increasing evidence that obesity predicts an increased risk of both hip OA and joint replacement, we found no association between BMI and lifetime risk.

Is physical activity a risk factor for primary knee or hip replacement due to osteoarthritis? A prospective cohort study

OBJECTIVE

To estimate prospectively any association between measures of physical activity and the risk of either primary knee or hip replacement due to osteoarthritis (OA).

METHODS

Eligible subjects (n = 39,023) were selected from participants in a prospective cohort study recruited 1990-1994. Primary knee and hip replacement for OA during 2001-2005 was determined by linking the cohort records to the National Joint Replacement Registry. A total physical activity level was computed, incorporating both intensity and frequency for different forms of physical activity obtained by questionnaire at baseline attendance.

RESULTS

There was a dose-response relationship between total physical activity level and the risk of primary knee replacement [hazards ratio (HR) 1.04, 95% CI 1.01-1.07 for an increase of 1 level in total physical activity]. Although vigorous activity frequency was associated with an increased risk of primary knee replacement (HR 1.42, 95% CI 1.08-1.86) for 1-2 times/week and HR 1.24 (95% CI 0.90-1.71) for ≥ 3 times/week), the p for trend was marginal (continuous HR 1.08, 95% CI 1.00-1.16, p = 0.05). The frequency of less vigorous activity or walking was not associated with the risk of primary knee replacement, nor was any measure of physical activity associated with the risk of primary hip replacement.

CONCLUSION

Increasing levels of total physical activity are positively associated with the risk of primary knee but not hip replacement due to OA. Physical activity might affect the knee and hip joints differently depending on the preexisting health status and anatomy of the joint, as well as the sort of physical activity performed.

Mild acetabular dysplasia and risk of osteoarthritis of the hip: a case-control study

OBJECTIVE

To determine whether mild variation in acetabular depth (AD) and shape is a risk factor for osteoarthritis (OA) of the hip.

METHODS

The unaffected contralateral hip of patients with unilateral hip OA was compared with hips of asymptomatic controls without hip OA, derived from the Nottingham Genetics Osteoarthritis and Lifestyle case-control study. Standardised anteroposterior x-rays of the pelvis were used to measure centre edge (CE) angle and AD. Cut-off points for narrow CE angle and shallow AD were calculated from the control group (mean -1.96 × SD). The relative risk of hip OA associated with each feature was estimated using OR and 95% CI and adjusted risks were calculated by logistic regression.

RESULTS

In controls, both the CE angle and the AD were lower in the left hip than in the right hip. The CE angle related to age in both hips, and AD of the right hip was lower in men than in women. The contralateral unaffected hip in patients with unilateral hip OA had a decreased CE angle and AD compared with controls, irrespective of side. The lowest tertile of the CE angle in contralateral hips was associated with an eightfold risk of OA (aOR 8.06, 95% CI 4.87 to 13.35) and the lowest tertile of AD was associated with a 2.5-fold risk of OA (aOR 2.53, 95% CI 1.28 to 5.00). Significant increases in the risk of OA were also found as the CE angle and AD decreased.

CONCLUSION

Constitutional mild acetabular dysplasia appears to increase the risk of hip OA.

The relationship between body mass index and hip osteoarthritis: a systematic review and meta-analysis

OBJECTIVE

Body mass index, a measure of relative weight, is increasingly recognized as an important risk factor for osteoarthritis, especially in weight bearing joints. The objective was to assess the association between body mass index and hip osteoarthritis susceptibility and investigate the difference between sex, study type and osteoarthritis definition.

METHODS

We did electronic searches of Medline, Embase and Cochrane library from the commencement to December 2009. A meta-analysis and meta-regression was executed to quantitatively assess the strength of associations between body mass index and hip osteoarthritis risk. Study-specific incremental estimates were standardized to determine the risk associated with a 5 kg/m(2) increase in body mass index.

RESULTS

Fourteen epidemiological studies were included. Our study showed that body mass index was significantly positive associated with hip osteoarthritis risk. A 5-unit increase in body mass index was related to an increased risk of hip osteoarthritis (RR: 1.11; 95%CI: 1.07, 1.16). The magnitudes of associations were similar in women as compared with men (women, RR: 1.10; 95%CI: 1.05, 1.15; men, RR: 1.08; 95%CI: 1.04, 1.12; p > 0.05). The summary estimates were 1.12 (95%CI: 1.02, 1.24) in case-control studies and 1.11 (95%CI: 1.06, 1.16) in cohort studies (p > 0.05). Body mass index was positively associated with hip osteoarthritis defined by radiography and/or clinical symptom (RR: 1.04; 95%CI: 1.00, 1.07) and clinical surgery (RR: 1.16; 95%CI: 1.11, 1.22) with no significant difference (p > 0.05).

CONCLUSION

Increased body mass index contributes to a positive effect on susceptibility to hip osteoarthritis. Associations between body mass index and hip osteoarthritis risk do not vary by sex, study design or osteoarthritis definition.

Associations of occupational tasks with knee and hip osteoarthritis: the Johnston County Osteoarthritis Project

OBJECTIVE

This cross-sectional study examined associations of occupational tasks with radiographic and symptomatic osteoarthritis (OA) in a community-based sample.

METHODS

Participants from the Johnston County Osteoarthritis Project (n = 2729) self-reported the frequency of performing 10 specific occupational tasks at the longest job ever held (never/seldom/sometimes vs often/always) and lifetime exposure to jobs that required spending > 50% of their time doing 5 specific tasks or lifting 22, 44, or 110 pounds 10 times weekly. Multivariable logistic regression models examined associations of each occupational task separately with radiographic and symptomatic knee and hip OA, controlling for age, race, gender, body mass index, prior knee or hip injury, and smoking.

RESULTS

Radiographic hip and knee OA were not significantly associated with any occupational tasks, but several occupational tasks were associated with increased odds of both symptomatic knee and hip OA: lifting > 10 pounds, crawling, and doing heavy work while standing (OR 1.4-2.1). More occupational walking and standing and less sitting were also associated with symptomatic knee OA, and more bending/twisting/reaching was associated with symptomatic hip OA. Exposure to a greater number of physically demanding occupational tasks at the longest job was associated with greater odds of both symptomatic knee and hip OA.

CONCLUSION

Our results confirm an association of physically demanding occupational tasks with both symptomatic knee and hip OA, including several specific activities that increased the odds of OA in both joint groups. These tasks represent possibilities for identifying and targeting at-risk individuals with preventive interventions.

Effects of body weight and alcohol consumption on insulin sensitivity

Background

Obesity is a risk factor for the development of insulin resistance, which can eventually lead to type-2 diabetes. Alcohol consumption is a protective factor against insulin resistance, and thus protects against the development of type-2 diabetes. The mechanism by which alcohol protects against the development of type-2 diabetes is not well known. To determine the mechanism by which alcohol improves insulin sensitivity, we fed water or alcohol to lean, control, and obese mice. The aim of this study was to determine whether alcohol consumption and body weights affect overlapping metabolic pathways and to identify specific target genes that are regulated in these pathways.

Method

Adipose tissue dysfunction has been associated with the development of type-2 diabetes. We assessed possible gene expression alterations in epididymal white adipose tissue (WAT). We obtained WAT from mice fed a calorie restricted (CR), low fat (LF Control) or high fat (HF) diets and either water or 20% ethanol in the drinking water. We screened the expression of genes related to the regulation of energy homeostasis and insulin regulation using a gene array composed of 384 genes.

Results

Obesity induced insulin resistance and calorie restriction and alcohol improved insulin sensitivity. The insulin resistance in obese mice was associated with the increased expression of inflammatory markers Cd68, Il-6 and Il-1α; in contrast, most of these genes were down-regulated in CR mice. Anti-inflammatory factors such as Il-10 and adrenergic beta receptor kinase 1 (Adrbk1) were decreased in obese mice and increased by CR and alcohol. Also, we report a direct correlation between body weight and the expression of the following genes: Kcnj11 (potassium inwardly-rectifying channel, subfamily J, member 11), Lpin2 (lipin2), and Dusp9 (dual-specificity MAP kinase phosphatase 9).

Conclusion

We show that alcohol consumption increased insulin sensitivity. Additionally, alterations in insulin sensitivity related with obesity were coupled with alterations in inflammatory genes. We provide evidence that alcohol may improve insulin sensitivity by up-regulating anti-inflammatory genes. Moreover, we have indentified potential gene targets in energy metabolic pathways and signal transducers that may contribute to obesity-related insulin resistance as well as calorie restriction and alcohol-induced insulin sensitivity.

Cancer risk is not increased after conventional hip arthroplasty

BACKGROUND AND PURPOSE

Wear debris from conventional total hip arthroplasty (THA) induces chromosomal aberrations and DNA damage, which may promote cancerogenesis. A long latent period is required for solid tumors. We therefore re-analyzed a large THA cohort for cancer.

PATIENTS AND METHODS

We updated a cohort of 24,636 patients with primary osteoarthritis and metal-on-polyethylene THA who had been entered in the Finnish Arthroplasty Register between 1980 and 1995, and linked it to the Finnish Cancer Registry for cancer risk assessment up to 2005. The mean follow-up time was 13 years. The numbers of cancer cases observed were compared with expected rates based on incidence in the general population.

RESULTS

The standardized incidence ratio (SIR) for the whole follow-up period was 0.95 (95% confidence interval (CI): 0.92-0.97). After 10 years of follow-up, the SIR was equal to that in the normal population (SIR = 0.98, 95% CI: 0.94-1.03). Incidence of lung cancer was low throughout the follow-up time and that of prostate cancer was slightly elevated. The incidence rates for all other forms of cancer did not deviate significantly from those in the normal population.

INTERPRETATION

We found no increased cancer risk in patients with conventional THA after an average of 13 years and up to 25 years of follow-up.

Characterization of individual radiographic features of hip osteoarthritis in African American and White women and men: the Johnston County Osteoarthritis Project

OBJECTIVE

To describe differences in radiographic features of hip osteoarthritis (OA) between African American and white men and women.

METHODS

We conducted a cross-sectional analysis of radiographic hip OA using baseline data from the Johnston County Osteoarthritis Project, using Kellgren/Lawrence (K/L) grade, and the presence, location, and severity of 4 individual radiographic features (joint space narrowing [JSN], subchondral cysts, sclerosis, and osteophytes). Sex-specific logistic regression was used to evaluate associations between race and individual radiographic features, adjusting for age, body mass index, education, and prior hip injury. Robust variance estimators via generalized estimating equations were used to account for correlation between hips from the same individual.

RESULTS

The sample (n = 2,739) comprised 57% women and 31% African American participants. Among women, African Americans and whites had a similar prevalence of hip OA, defined as K/L grade > or =2 (23% versus 22%), but African American women were significantly more likely to have superior or medial JSN, moderate or severe axial JSN, medial or lateral osteophytes, and subchondral cysts. Among men, 21% of African Americans and 17% of whites had hip OA; African American men were more likely to have superior or medial JSN and lateral osteophytes, but were less likely to have axial JSN.

CONCLUSION

Individual radiographic features and patterns of hip OA differed by race among women and men, suggesting the possibility of anatomic and/or developmental variation in the hip joint. African Americans have an increased frequency of features that have been predictive of hip replacement in other populations, a finding worthy of further study.

The robust association between childhood physical abuse and osteoarthritis in adulthood: findings from a representative community sample

OBJECTIVE

Research suggests a role of early-life trauma in the development of arthritis. This study investigated the relationship between childhood physical abuse and osteoarthritis (OA) while controlling for age, sex, race, and socioeconomic status (SES), in addition to the following types of risk factors for OA: 1) concurrent childhood stressors, 2) adult health behaviors, and 3) depression.

METHODS

Data from the provinces of Manitoba and Saskatchewan were selected from the 2005 Canadian Community Health Survey (n = 13,093). Respondents with missing arthritis data or with arthritis types other than OA were excluded (n = 1,985). Of the 11,108 remaining respondents, 6.9% (n = 854) reported childhood physical abuse by someone close to them, and 10.1% (n = 1,452) reported that they had been diagnosed with OA by a health professional. The regional-level response rate was 84%.

RESULTS

When adjusting for all 3 types of risk factors, a significant association between childhood physical abuse and OA was found (odds ratio [OR] 1.56, 95% confidence interval [95% CI] 1.21-2.00). In contrast, when adjusting for age, sex, race, and SES only, the OR was 1.99 (95% CI 1.57-2.52).

CONCLUSION

The association between childhood physical abuse and OA remained significant, even after controlling for many risk factors that may mediate the relationship. Further research is needed to investigate potential pathways through which arthritis develops as a consequence of childhood physical abuse.

Changes in proximal femoral mineral geometry precede the onset of radiographic hip osteoarthritis: The study of osteoporotic fractures

OBJECTIVE

Radiographic hip osteoarthritis (RHOA) is associated with increased hip areal bone mineral density (aBMD). This study was undertaken to examine whether femoral geometry is associated with RHOA independent of aBMD.

METHODS

Participants in the Study of Osteoporotic Fractures in whom pelvic radiographs had been obtained at visits 1 and 5 (mean 8.3 years apart) and hip dual x-ray absorptiometry (DXA) had been performed (2 years after baseline) were included. Prevalent and incident RHOA phenotypes were defined as composite (osteophytes and joint space narrowing [JSN]), atrophic (JSN without osteophytes), or osteophytic (femoral osteophytes without JSN). Analogous definitions of progression were based on minimum joint space and total osteophyte score. Hip DXA scans were assessed using the Hip Structural Analysis program to derive geometric measures, including femoral neck length, width, and centroid position. Relative risks and 95% confidence intervals for prevalent, incident, and progressive RHOA per SD increase in geometric measure were estimated in a hip-based analysis using multinomial logistic regression with adjustment for age, body mass index, knee height, and total hip aBMD.

RESULTS

In 5,245 women (mean age 72.6 years), a wider femoral neck with a more medial centroid position was associated with prevalent and incident osteophytic and composite RHOA phenotypes (P < 0.05). Increased neck width and centroid position were associated with osteophyte progression (both P < 0.05). No significant geometric associations with atrophic RHOA were found.

CONCLUSION

Differences in proximal femoral bone geometry and spatial distribution of bone mass occur early in hip OA and predict prevalent, incident, and progressive osteophytic and composite phenotypes, but not the atrophic phenotype. These bone differences may reflect responses to loading occurring early in the natural history of RHOA.

What epidemiology has told us about risk factors and aetiopathogenesis in rheumatic diseases

This article will review how epidemiological studies have advanced our knowledge of both genetic and environmental risk factors for rheumatic diseases over the past decade. The major rheumatic diseases, including rheumatoid arthritis, juvenile idiopathic arthritis, psoriatic arthritis, ankylosing spondylitis, systemic lupus erythematosus, scleroderma, osteoarthritis, gout, and fibromyalgia, and chronic widespread pain, will be covered. Advances discussed will include how a number of large prospective studies have improved our knowledge of risk factors, including diet, obesity, hormones, and smoking. The change from small-scale association studies to genome-wide association studies using gene chips to reveal new genetic risk factors will also be reviewed.

Sex differences in the association between body mass index and total hip or knee joint replacement resulting from osteoarthritis

OBJECTIVE

To examine the association between body mass index (BMI) and osteoarthritis (OA) leading to total hip (THR) or knee (TKR) joint replacement.

METHODS

Case-control study design. All patients still living in Iceland who had had a THR or TKR resulting from OA before the end of 2002 were invited to participate. First-degree relatives of participating patients served as controls. A total of 1473 patients (872 women) and 1103 controls (599 women), all born between 1910 and 1939 and who had answered a questionnaire including questions about height and weight, were analysed. A randomly selected sample, representative of the Icelandic population, was used as a secondary control group.

RESULTS

The OR, adjusted for age, occupation and presence of hand OA, for having a THR was 1.1 (95% CI 0.9 to 1.5) for overweight men and 1.7 (95% CI 1.0 to 2.9) for obese men. The OR for having a TKR was 1.7 (95% CI 1.1 to 2.6) for overweight men and 5.3 (95% CI 2.8 to 10.1) for obese men. The OR for having a THR was 1.0 (95% CI 0.8 to 1.3) for overweight women and 1.0 (95% CI 0.6 to 1.5) for obese women. The OR for having a TKR was 1.6 (95% CI 1.1 to 2.2) for overweight women and 4.0 (95% CI 2.6 to 6.1) for obese women.

CONCLUSION

This study supports a positive association between high BMI and TKR in both sexes, but for THR the association with BMI seems to be weaker, and possibly negligible for women.

Incidence of severe knee and hip osteoarthritis in relation to different measures of body mass: a population-based prospective cohort study

OBJECTIVE

To determine in a prospective population-based cohort study relationships between different measures of body mass and the incidence of severe knee and hip osteoarthritis defined as arthroplasty of knee or hip due to osteoarthritis.

MATERIALS AND METHODS

Body mass index (BMI), waist circumference, waist-hip ratio (WHR), weight and percentage of body fat (BF%) were measured at baseline in 11,026 men and 16,934 women from the general population. The incidence of osteoarthritis over 11 years was monitored by linkage with the Swedish hospital discharge register.

RESULTS

471 individuals had knee osteoarthritis and 551 had hip osteoarthritis. After adjustment for age, sex, smoking and physical activity, the relative risks (RR) of knee osteoarthritis (fourth vs first quartile) were 8.1 (95% CI 5.3 to 12.4) for BMI, 6.7 (4.5 to 9.9) for waist circumference, 6.5 (4.6 to 9.43) for weight, 3.6 (2.6 to 5.0) for BF% and 2.2 (1.7 to 3.0) for WHR. Corresponding RR for hip osteoarthritis were 2.6 (2.0 to 3.4) for BMI, 3.0 (2.3 to 4.0) for weight, 2.5 (1.9 to 3.3) for waist, 1.3 (0.99 to 1.6) for WHR and 1.5 (1.2 to 2.0) for BF%.

CONCLUSION

All measures of overweight were associated with the incidence of knee osteoarthritis, with the strongest relative risk gradient observed for BMI. The incidence of hip osteoarthritis showed smaller but significant differences between normal weight and obesity. Our results support a major link between overweight and biomechanics in increasing the risk of knee and hip osteoarthritis in men and women.

Relationship between body adiposity measures and risk of primary knee and hip replacement for osteoarthritis: a prospective cohort study

INTRODUCTION

Total joint replacement is considered a surrogate measure for symptomatic end-stage osteoarthritis. It is unknown whether the adipose mass and the distribution of adipose mass are associated with the risk of primary knee and hip replacement for osteoarthritis. The aim of the present investigation was to examine this in a cohort study.

METHODS

A total of 39,023 healthy volunteers from Melbourne, Australia were recruited for a prospective cohort study during 1990 to 1994. Their body mass index, waist circumference, and waist-to-hip ratio were obtained from direct anthropometric measurements. The fat mass and percentage fat were estimated from bioelectrical impedance analysis. Primary knee and hip replacements for osteoarthritis between 1 January 2001 and 31 December 2005 were determined by data linkage to the Australian Orthopaedic Association National Joint Replacement Registry. Cox proportional hazards regression models were used to estimate the hazard ratios (HRs) for primary joint replacement associated with each adiposity measure.

RESULTS

Comparing the fourth quartile with the first, there was a threefold to fourfold increased risk of primary joint replacement associated with body weight (HR = 3.44, 95% confidence interval (CI) = 2.83 to 4.18), body mass index (HR = 3.44, 95% CI = 2.80 to 4.22), fat mass (HR = 3.51, 95% CI = 2.87 to 4.30), and percentage fat (HR = 2.99, 95% CI = 2.46 to 3.63). The waist circumference (HR = 2.77, 95% CI = 2.26 to 3.39) and waist-to-hip ratio (HR = 1.46, 95% CI = 1.21 to 1.76) were less strongly associated with the risk. Except for the waist-to-hip ratio, which was not significantly associated with hip replacement risk, all adiposity measures were associated with the risk of both knee and hip joint replacement, and were significantly stronger risk factors for knee.

CONCLUSIONS

Risk of primary knee and hip joint replacement for osteoarthritis relates to both adipose mass and central adiposity. This relationship suggests both biomechanical and metabolic mechanisms associated with adiposity contribute to the risk of joint replacement, with stronger evidence at the knee rather than the hip.

Nonspherical femoral head shape (pistol grip deformity), neck shaft angle, and risk of hip osteoarthritis: a case-control study

OBJECTIVE

To determine whether 2-dimensional measures of femoral head shape and angle are associated with hip osteoarthritis (OA).

METHODS

We compared cases with symptomatic radiographic hip OA with asymptomatic controls with no radiographic hip OA. On anteroposterior pelvis radiographs, we measured "pistol grip deformity" for each hip (visually categorized as nonspherical, indeterminate, or spherical), the femoral head-to-femoral neck ratio as an interval measure of femoral head shape, and the femoral neck shaft angle. The relative risk of hip OA associated with each feature was estimated using odds ratios (ORs) and 95% confidence intervals (95% CIs), adjusted for possible confounders using a logistic regression model.

RESULTS

Of 1,007 cases, 965 had definite radiographic hip OA; of 1,123 controls, 1,111 had no radiographic OA. The prevalence of pistol grip deformity in at least 1 hip was 3.61% in controls and 17.71% in cases (OR 6.95 [95% CI 4.64-10.41]), and the prevalence of abnormal femoral head-to-femoral neck ratio in at least 1 hip was 3.70% in controls and 24.27% in cases (OR 12.08 [95% CI 8.05-18.15]). The risk of hip OA increased as the femoral head-to-femoral neck ratio decreased (P for trend<0.001) and with each extreme of neck shaft angle (P<0.05). In cases with unilateral hip OA, the prevalence of abnormal femoral head-to-femoral neck ratio in the unaffected hip was 2 times greater than that in controls (OR 1.82 [95% CI 1.07-3.07]); in contrast, an abnormally low, but not abnormally high, neck shaft angle was more common in unaffected hips than in controls (OR 1.79 [95% CI 1.03-3.14]).

CONCLUSION

Our findings indicate that pistol grip deformity is associated with hip OA. The increased prevalence of pistol grip deformity and an abnormally low neck shaft angle in unaffected hips of cases with unilateral OA suggests that they are risk factors for development of hip OA. However, both a nonspherical head shape and an increase in neck shaft angle may occur as a consequence of OA.

Obesity and osteoarthritis in knee, hip and/or hand: an epidemiological study in the general population with 10 years follow-up

Background

Obesity is one of the most important risk factors for osteoarthritis (OA) in knee(s). However, the relationship between obesity and OA in hand(s) and hip(s) remains controversial and needs further investigation. The purpose of this study was to investigate the impact of obesity on incident osteoarthritis (OA) in hip, knee, and hand in a general population followed in 10 years.

Methods

A total of 1854 people aged 24–76 years in 1994 participated in a Norwegian study on musculoskeletal pain in both 1994 and 2004. Participants with OA or rheumatoid arthritis in 1994 and those above 74 years in 1994 were excluded, leaving n = 1675 for the analyses. The main outcome measure was OA diagnosis at follow-up based on self-report. Obesity was defined by a body mass index (BMI) of 30 and above.

Results

At 10-years follow-up the incidence rates were 5.8% (CI 4.3–7.3) for hip OA, 7.3% (CI 5.7–9.0) for knee OA, and 5.6% (CI 4.2–7.1) for hand OA. When adjusting for age, gender, work status and leisure time activities, a high BMI (> 30) was significantly associated with knee OA (OR 2.81; 95%CI 1.32–5.96), and a dose-response relationship was found for this association. Obesity was also significantly associated with hand OA (OR 2.59; 1.08–6.19), but not with hip OA (OR 1.11; 0.41–2.97). There was no statistically significant interaction effect between BMI and gender, age or any of the other confounding variables.

Conclusion

A high BMI was significantly associated with knee OA and hand OA, but not with hip OA.

The effect of moderate impact exercise on skeletal integrity in master athletes

We measured bone mineral density (BMD) in senior athletes competing in running and swimming events and compared results to those of sedentary controls. Total body BMD was greatest among runners suggesting that moderate impact activities continue to play a role in maintaining skeletal integrity with age.

INTRODUCTION

The role of moderate impact exercise in maintaining skeletal integrity as we age remains unclear.

METHODS

To determine the effect of moderate impact exercise on skeletal integrity in the elderly, we recruited master athletes, including 44 runners (moderate impact exercise) and 43 swimmers, competing in the 2005 National Senior Olympic Games and 87 non-athletes, all over the age of 65 years. Height, weight, calcium, vitamin D intake, bone mineral density (BMD) of the total body, spine, hip (total hip, femoral neck, trochanter, intertrochanter), forearm (1/3 distal radius), and heel ultrasound, and Z-scores were characterized by mean +/- SD and compared by analysis of variance. T-scores were used to determine sites of osteopenia and osteoporosis.

RESULTS

Total body BMD of runners was significantly greater than that of controls (1.11 +/- 0.13 versus 1.10 +/- 0.13 g/cm(2), p < 0.05) and marginally greater than that of swimmers when adjusted for age and weight. Heel ultrasound bone mass of runners was significantly greater than that of swimmers or controls. Runners also had higher BMD in the total hip, intertrochanter and 1/3 distal radius when compared to swimmers.

CONCLUSION

These findings suggest that moderate impact exercise contributes to skeletal integrity in older age.

The epidemiology of obesity and gastrointestinal and other diseases: an overview

The worldwide prevalence of obesity continues to increase, with devastating implications for overall health. Epidemiological trends indicate the primary contributors are environmental (e.g., increased caloric intake, lack of exercise), although the evidence is surprisingly equivocal. Increased body mass index (BMI) is associated with an increase in all-cause mortality and in diseases related to this increasing mortality rate, such as diabetes mellitus, cardiovascular disease, and cancer, including those of the gastrointestinal system. Some of these associations are even more pronounced when obesity is measured by waist-to-hip ratio, a marker of visceral adipose tissue, versus BMI. Higher BMI is related to increased risk of developing gall stones, and obese patients experience GI symptoms, such as vomiting and diarrhea, more often compared with those of normal body mass. Although the exact cause remains uncertain, these symptoms may be connected to eating habits or to changes in gastrointestinal motility.