Symptomatic slow-acting drugs for osteoarthritis (SYSADOAs) are recommended for the medium- to long-term management of knee osteoarthritis (OA) due to their abilities to control pain, improve function and delay joint structural changes. Among SYSADOAs, evidence is greatest for the patented crystalline glucosamine sulfate (pCGS) formulation (Mylan). Glucosamine is widely available as glucosamine sulfate (GS) and glucosamine hydrochloride (GH) preparations that vary substantially in molecular form, pharmaceutical formulation and dose regimen. Only pCGS is given as a highly bioavailable once-daily dose (1500 mg), which consistently delivers the plasma levels of around 10 μmol/L required to inhibit interleukin-1-induced expression of genes involved in the pathophysiology of joint inflammation and tissue destruction. Careful consideration of the evidence base reveals that only pCGS reliably provides a moderate effect size on pain that is higher than paracetamol and equivalent to non-steroidal anti-inflammatory drugs (NSAIDs), while non-crystalline GS and GH fail to reach statistical significance for pain reduction. Chronic administration of pCGS has disease-modifying effects, with a reduction in need for total joint replacement lasting for 5 years after treatment cessation. Pharmacoeconomic studies of pCGS demonstrate long-term reduction in additional pain analgesia and NSAIDs, with a 50% reduction in costs of other OA medication and healthcare consultations. Consequently, pCGS is the logical choice, with demonstrated medium-term control of pain and lasting impact on disease progression. Physician and patient education on the differentiation of pCGS from other glucosamine formulations will help to improve treatment selection, increase treatment adherence, and optimize clinical benefit in OA.
OBJECTIVES: Hand osteoarthritis (HOA) is common but little is known about how HOA has impact on disability and quality of life (QoL).We aim to identify important domains of concern among participants suffering from symptomatic HOA in Singapore, representing an Asian socio-cultural context.
METHODS: A qualitative study using a focus group technique was performed. We ran focus groups stratified by gender, ethnicity and language. Two independent, trained analysts identified relevant categories and assigned codes to text segments through open coding, with discrepancies resolved through consensus. The final lists of domains and subthemes descriptive of QoL were then compared to the following commonly used HOA specific instruments: Functional Index for Hand Osteoarthritis (FIHOA), Score for Assessment and quantification of Chronic Rheumatic Affections of the Hand (SACRAH), Australian/Canadian Hand Osteoarthritis Index (AUSCAN); and Health Assessment Questionnaire (HAQ).
RESULTS: Twenty-six patients (23 women, three men; 24 Chinese and two Malay; mean ± SD age 62.9 ± 7.5 years) with symptomatic HOA according to the American College of Rheumatology Classification Criteria participated in seven focus groups. Two and five focus groups were conducted in Chinese and English, respectively. The qualitative analysis revealed pain, stiffness and functional disability as the main domains. However, psychological consequences, aesthetic concerns, participation in leisure activities, participation in family roles were important concepts from the focus groups which were not covered by existing instruments. Impact on work productivity by HOA and the unmet health care need is revealed.
CONCLUSION: The domains of concepts important to people with HOA in an Asian socio-cultural context are not fully represented in the most commonly used instruments. Further studies on the selection of main domains relevant to HOA patients are necessary.
Study site: Rheumatology outpatient clinic, Singapore General Hospital