Duration of physical activity, sitting, sleep and the risk of total knee replacement among Chinese in Singapore, the Singapore Chinese Health Study

Exercise Therapy for Knee and Hip Osteoarthritis: Is There An Ideal Prescription?

Purpose of review

Exercise therapy is the first line treatment for patients with knee and hip osteoarthritis (OA) but is consistently underutilized. In this review, we aim to provide health care professionals with an overview of the latest evidence in the areas of exercise therapy for OA, which can serve as a guide for incorporating the ideal exercise therapy prescription in the overall management plan for their patients with OA.

Recent findings

Evidence continues to be produced supporting the use of exercise therapy for all patients with knee or hip OA. Ample evidence exists suggesting exercise therapy is a safe form of treatment, for both joint structures and the patient overall. Several systematic reviews show that exercise therapy is likely to improve patient outcomes, regardless of disease severity or comorbidities. However, no single type of exercise therapy is superior to others.

Summary

Health care practitioners and patients should be encouraged to incorporate exercise therapy into treatment plans and can be assured of the safety profile and likelihood of improvement in important patient outcomes. Since no single exercise therapy program shows vastly superior benefit, patient preference and contextual factors should be central to the shared decision-making process when selecting and individualising appropriate exercise therapy prescriptions.

Food sources of dietary fibre and risk of total knee replacement related to severe osteoarthritis, the Singapore Chinese Health Study

Objectives

We aimed to evaluate the association between fibre intake and its food sources, and the risk of total knee replacement (TKR) due to severe knee osteoarthritis (KOA).

Methods

We used data from the Singapore Chinese Health Study, a prospective cohort study that recruited 63 257 participants aged 45–74 years from 1993 to 1998. At baseline, we assessed diet using a validated 165-item semiquantitative food frequency questionnaire, together with body mass index (BMI) and lifestyle factors. Incident TKR cases were identified via record linkage with nationwide hospital discharge database through 2017.

Results

There were 2816 cases of incident TKR due to severe KOA. The total fibre intake at baseline was not associated with the risk of TKR after adjustment for confounders. Among the food sources of fibre, higher intake of legumes was associated with a lower risk of TKR in a dose-dependent manner; compared with those having the lowest quartile intake, HR (95% CI) was 0.86 (0.76, 0.96) for those having the highest quartile intake (p for trend=0.004). This association was consistent after including BMI in the model and homogeneous across BMI categories. The consumption of other fibre sources, namely grain products, nuts and seeds, soy food, fruits and vegetables, was not associated with the risk of TKR.

Conclusion

Intake of legumes, but not total fibre, was associated with a reduced risk of TKR. Further research is needed to replicate our findings and to evaluate possible biological mechanisms that could explain the effect of dietary legumes on pathogenesis or progression of KOA.

Occupational Risk in Knee Osteoarthritis: A Systematic Review and Meta-Analysis of Observational Studies

OBJECTIVE

To assess the association between occupational exposures and knee osteoarthritis (OA).

METHODS

We systematically searched for observational studies that examined the relationship between occupational exposures and knee OA and total knee replacement. Four databases were searched up to October 1, 2019. Two reviewers independently assessed study quality using the Newcastle-Ottawa Scale and evidence quality using the Grading of Recommendations Assessment, Development and Evaluation approach. Subgroup meta-analyses were conducted for important study characteristics and each type of occupational exposure. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were estimated for the meta-analysis using random-effects models.

RESULTS

Eighty eligible studies were identified including 25 case-control (n = 20,505 total participants), 36 cross-sectional (n = 139,463 total participants), and 19 cohort studies (n = 16,824,492 total participants). A synthesis of 71 studies suggested increased odds of knee OA (OR 1.52 [95% CI 1.37-1.69]) by combining different physically demanding jobs and occupational activities as compared to sedentary occupations and/or low-exposure groups. Odds of knee OA were greater in males and in industry-based studies and studies assessing lifetime occupational exposures. There were 9 specific job titles that were associated with knee OA, including farmer, builder, metal worker, and floor layer. Occupational lifting, kneeling, climbing, squatting, and standing were all associated with higher odds of knee OA as compared to the odds of knee OA in sedentary workers.

CONCLUSION

Strenuous, physically demanding occupations and occupational activities were associated with increased odds of knee OA as supported by moderate-quality evidence. Specifically, agricultural and construction sectors, which typically involve heavy lifting, frequent climbing, prolonged kneeling, squatting, and standing, carried increased odds of knee OA.

Occupation and risk of knee osteoarthritis and knee replacement: A longitudinal, multiple-cohort study

OBJECTIVES

To examine the effect of occupation on knee osteoarthritis (OA) and total knee replacement (TKR) in working-aged adults.

METHODS

We used longitudinal data from the Chingford, Osteoarthritis Initiative (OAI) and Multicentre Osteoarthritis (MOST) studies. Participants with musculoskeletal disorders and/or a history of knee-related surgery were excluded. Participants were followed for up to 19-years (Chingford), 96-months (OAI) and 60-months (MOST) for incident outcomes including radiographic knee OA (RKOA), symptomatic RKOA and TKR. In those with baseline RKOA, progression was defined as the time from RKOA incidence to primary TKR. Occupational job categories and work-place physical activities were assigned to levels of workload. Logistic regression was used to examine the relationship between workload and incident outcomes with survival analyses used to assess progression (reference group: sedentary occupations).

RESULTS

Heavy manual occupations were associated with a 2-fold increased risk (OR: 2.07, 95% CI 1.03 to 4.15) of incident RKOA in the OAI only. Men working in heavy manual occupations in MOST (2.7, 95% CI 1.17 to 6.26) and light manual occupations in OAI (2.00, 95% CI 1.09 to 3.68) had a 2-fold increased risk of incident RKOA. No association was observed among women. Increasing workload was associated with an increased risk of symptomatic RKOA in the OAI and MOST. Light work may be associated with a decreased risk of incident TKR and disease progression.

CONCLUSION

Heavy manual work carries an increased risk of incident knee OA; particularly among men. Workload may influence the occurrence of TKR and disease progression.

Calibration of a physical functioning item bank for measurement of health-related quality of life in Singapore

PURPOSE

We aimed to develop and calibrate an item bank to measure physical function (PF) in Singapore, a multi-ethnic city in Southeast Asia.

METHODS

We recruited participants from community and hospital settings stratified for age and gender, with and without medical conditions to administer candidate pool of 61-items derived from the people's perspectives. We calibrated their responses using Samejima's graded response model of item response theory (IRT), including model assumptions, model fit, differential item functioning (DIF), and concurrent and known-groups validity.

RESULTS

496 participants (50% male; 41% above 50 years old; 33.3% Chinese, 32.7% Malay and 34.1% Indian; 35% without chronic illness) were included in the calibration of item bank. 6 items were excluded due to mis-fit and local dependence. Redundancies in the response level was collapsed and re-scoring, while preserving the 5-level response structure. We found the final 55-item PF bank had adequate fit to IRT assumptions of unidimensionality, local independence and monotonicity. Items generally showed discernible ceiling effects with latent scores between - 3.5 to + 1.5. We found no DIF with gender, ethnicity or education. The PF scores correlated in the hypothesized direction with self-reported global health (Spearman's rho =  - 0.35, 95% confidence intervals - 0.43 to - 0.27) and discriminated between groups stratified by age, gender and medical conditions.

CONCLUSION

The 55-item Singapore PF item bank provides an adequate tool for measuring the lower end of PF, with greatest potential utility in healthcare settings where restoration to normal physical functioning is the goal of intervention.

Genetic risk, adherence to a healthy lifestyle, and type 2 diabetes risk among 550,000 Chinese adults: results from 2 independent Asian cohorts

BACKGROUND

Whether genetic susceptibility to type 2 diabetes is modified by a healthy lifestyle among Chinese remains unknown.

OBJECTIVES

The aim of the study was to determine whether genetic risk and adherence to a healthy lifestyle contribute independently to the risk of developing type 2 diabetes.

METHODS

We defined a lifestyle score using BMI, alcohol intake, smoking, physical activities, and diets in 461,030 participants from the China Kadoorie Biobank and 38,434 participants from the Singapore Chinese Health Study. A genetic risk score was constructed based on type 2 diabetes loci among 100,175 and 16,172 participants in each cohort, respectively. A Cox proportional-hazards model was used to estimate the interaction between genetic and lifestyle factors on the risk of type 2 diabetes.

RESULTS

In 2 independent Asian cohorts, we consistently found a healthy lifestyle (the bottom quintile of lifestyle score) was associated with a substantially lower risk of type 2 diabetes than an unhealthy lifestyle (the top quintile of lifestyle score) regardless of genetic risk. In those at a high genetic risk, the risk of type 2 diabetes was 57% lower among participants with a healthy lifestyle than among those with an unhealthy lifestyle in the pooled cohorts. Among participants at high genetic risk, the standardized 10-y incidence of type 2 diabetes was 7.11% in those with an unhealthy lifestyle vs. 2.45% in those with a healthy lifestyle.

CONCLUSIONS

In 2 independent cohorts involving 558,302 Chinese participants, we did not observe an interaction between genetics and lifestyle with type 2 diabetes risk, but our findings provide replicable evidence to show lifestyle factors and genetic factors were independently associated with the risk of type 2 diabetes. Within any genetic risk category, a healthy lifestyle was associated with a significantly lower risk of type 2 diabetes among the Chinese population.

Ex vivo physiological compression of human osteoarthritis cartilage modulates cellular and matrix components

Mechanical stimulation appears to play a key role in cartilage homeostasis maintenance, but it can also contribute to osteoarthritis (OA) pathogenesis. Accumulating evidence suggests that cartilage loading in the physiological range contributes to tissue integrity maintenance, whereas excessive or reduced loading have catabolic effects. However, how mechanical stimuli can regulate joint homeostasis is still not completely elucidated and few data are available on human cartilage. We aimed at investigating human OA cartilage response to ex vivo loading at physiological intensity. Cartilage explants from ten OA patients were subjected to ex vivo controlled compression, then recovered and used for gene and protein expression analysis of cartilage homeostasis markers. Compressed samples were compared to uncompressed ones in presence or without interleukin 1β (IL-1β) or interleukin 4 (IL-4). Cartilage explants compressed in combination with IL-4 treatment showed the best histological scores. Mechanical stimulation was able to significantly modify the expression of collagen type II (collagen 2), aggrecan, SOX9 transcription factor, cartilage oligomeric matrix protein (COMP), collagen degradation marker C2C and vascular endothelial growth factor (VEGF). Conversely, ADAMTS4 metallopeptidase, interleukin 4 receptor alpha (IL4Rα), chondroitin sulfate 846 epitope (CS846), procollagen type 2 C-propeptide (CPII) and glycosaminoglycans (GAG) appeared not modulated. Our data suggest that physiological compression of OA human cartilage modulates the inflammatory milieu by differently affecting the expression of components and homeostasis regulators of the cartilage extracellular matrix.