Development and preliminary evaluation of the OsteoArthritis Questionnaire (OA-Quest): a psychometric study

Fish oil supplementation reduces osteoarthritis-specific pain in older adults with overweight/obesity

Objectives

OA is a leading cause of chronic pain and disability. Next to inflammation, vascular pathology has been hypothesized to play a role in its aetiology and progression. Owing to side effects and the low efficacy of pharmacological treatments, dietary supplements are popular as alternative treatments, but evidence of efficacy is limited. We tested whether fish oil and curcumin supplementation can reduce chronic pain and OA burden in older adults.

Methods

A 16-week randomized, double-blind, placebo-controlled, 2 × 2 factorial design supplementation trial with fish oil (2000 mg/day docosahexaenoic acid + 400 mg/day eicosapentaenoic acid), curcumin (160 mg/day) or a combination of both was undertaken in sedentary overweight/obese older adults. Secondary outcomes included treatment-induced changes in self-reported chronic pain and OA burden and whether changes were related to changes in small artery elasticity (surrogate marker for microvascular function), CRP (inflammatory marker) and well-being.

Results

The majority of participants (131 of 152) reported chronic pain, which was predominantly OA specific. Fish oil significantly reduced OA-specific pain (P = 0.002, Cohen’s d = 0.56) and burden (P = 0.015, Cohen’s d = 0.45) compared with no fish oil treatment; reductions were correlated with improvements in microvascular function and well-being. Curcumin, alone or in combination with fish oil, did not reduce pain measures.

Conclusion

Our findings indicate potential for fish oil to alleviate OA pain and burden in overweight/obese older adults. Further investigations should be undertaken in patients with clinically diagnosed OA to evaluate fish oil alone and as an adjunct to conventional pharmacotherapy and to investigate underlying mechanisms.

Trial registration

Australian and New Zealand Clinical Trials Register, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=370788, ACTRN12616000732482p.

Psychometric evaluation supported construct validity, temporal stability, and responsiveness of the Osteoarthritis Questionnaire

OBJECTIVES

The Osteoarthritis Questionnaire (OA-Quest) is a new measure of individual burden of osteoarthritis, composing seven brief (4-11 items; total 42 items), independent scales. This study describes the psychometric evaluation of the OA-Quest. Specifically, temporal stability, convergent and discriminant validity, and responsiveness of the OA-Quest to joint replacement surgery were examined.

STUDY DESIGN AND SETTING

Participants were drawn from rheumatology (n = 62), orthopedic (n = 90), and community (n = 175) settings. Temporal stability of the OA-Quest was evaluated over a 2-week period and was assessed with intraclass correlation coefficients. Responsiveness was assessed with standardized effect sizes and paired samples t-tests. Convergent and discriminant validity was assessed with a multitrait multimethod confirmatory factor analysis (MTMM CFA).

RESULTS

The OA-Quest scales had high temporal stability, with intraclass correlation coefficients between 0.75 (lost productivity) and 0.94 (physical limitations) and showed improvements of expected magnitude and direction 3 months after joint replacement surgery, supporting their responsiveness. MTMM CFA supported the convergent and discriminant validity of the OA-Quest, demonstrated by adequate model fit (χ² = 483.54, df = 184, P < 0.001, comparative fit index = 0.95, Tucker-Lewis index = 0.93, root mean square error of approximation = 0.07, standardized root mean square residual = 0.06) and factor loadings of the expected magnitude and direction.

CONCLUSION

The OA-Quest has strong evidence of temporal stability, construct validity, and is responsive to change following joint replacement surgery.

Application of validity theory and methodology to patient-reported outcome measures (PROMs): building an argument for validity

BACKGROUND

Data from subjective patient-reported outcome measures (PROMs) are now being used in the health sector to make or support decisions about individuals, groups and populations. Contemporary validity theorists define validity not as a statistical property of the test but as the extent to which empirical evidence supports the interpretation of test scores for an intended use. However, validity testing theory and methodology are rarely evident in the PROM validation literature. Application of this theory and methodology would provide structure for comprehensive validation planning to support improved PROM development and sound arguments for the validity of PROM score interpretation and use in each new context.

OBJECTIVE

This paper proposes the application of contemporary validity theory and methodology to PROM validity testing.

ILLUSTRATIVE EXAMPLE

The validity testing principles will be applied to a hypothetical case study with a focus on the interpretation and use of scores from a translated PROM that measures health literacy (the Health Literacy Questionnaire or HLQ).

DISCUSSION

Although robust psychometric properties of a PROM are a pre-condition to its use, a PROM's validity lies in the sound argument that a network of empirical evidence supports the intended interpretation and use of PROM scores for decision making in a particular context. The health sector is yet to apply contemporary theory and methodology to PROM development and validation. The theoretical and methodological processes in this paper are offered as an advancement of the theory and practice of PROM validity testing in the health sector.

Association between osteoarthritis and mental health in a Korean population: a nationwide study

AIM

Osteoarthritis (OA) is a chronic disease and has become a major health problem in recent years. OA causes chronic pain and disability and can induce mental disorders such as stress perception, depression and suicidal ideation. We investigated the incidence of perceived stress, depressed mood and suicidal ideation in OA patients, using the 2010-2012 Korea National Health and Nutrition Examination Survey (KNHANES).

METHOD

A total of 8271 participants were included (3580 male and 4691 female). OA patients were defined as participants with knee/hip joint pain and radiographic changes of the knee/hip joints. Mental disorders included stress perception, depression and suicidal ideation. Odds ratios (ORs) and 95% confidence intervals (95% CIs) for mental disorders were calculated according to the OA.

RESULTS

In the multiple logistic regression model, compared to the non-OA group, the ORs of high stress perception, depression and suicidal ideation were 1.59 (95% CI 1.10-2.31), 1.52 (95% CI 1.01-2.29) and 1.90 (95% CI 1.33-2.72), respectively, in male, and 1.41 (95% CI 1.19-1.68), 1.27 (95% CI 1.04-1.54) and 1.49 (95% CI 1.25-1.78), respectively, in female.

CONCLUSION

OA is associated with impaired mental health. OA patients had high stress perception, depression and suicidal ideation. More numbers of male with OA had much more mental disorders than female with OA.