Rheumatoid Arthritis: van Staa TP

van Staa TP. · Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands. · Calcif Tissue Int. · Pubmed #16969593 No free full text.

Abstract: Oral glucocorticoids (GCs) are frequently used in the treatment of inflammatory conditions, such as rheumatoid arthritis or asthma. They have adverse skeletal effects, primarily through reductions in bone formation and osteocyte apoptosis. Several findings indicate that changes in the quality of bone may significantly contribute to the increased risk of fracture and that loss of BMD only partially explains the increased risk of fracture in oral GC users. Epidemiological studies have found that the increases in the risk of fracture in oral GC users are dose dependent and occur within three months of starting GC therapy. Daily doses of >2.5 mg prednisone equivalent have been associated with increases in the risk of fractures and randomised studies reported adverse skeletal effects with daily doses as low as 5 mg. After discontinuation of GC treatment, the risk of fracture may reduce towards baseline levels unless patients previously used high cumulative doses of oral GCs. Users of inhaled GCs have also an increased risk of fracture, especially at higher doses. But it is likely that this excess risk is related to the severity of the underlying respiratory disease, rather than to the inhaled GC therapy. It has been recommended that patients who start on oral GC therapy should receive calcium and vitamin D supplementation. Patients with a higher risk of fracture should also receive a bisphosphonate.

Edwards CJ, Cooper C, Fisher D, Field M, van Staa TP, Arden NK. · University of Southampton, and Southampton General Hospital, Southampton, UK. · Arthritis Rheum. · Pubmed #17907232 links to  free full text

Abstract: OBJECTIVE: To evaluate the effect of disease-modifying antirheumatic drugs (DMARDs) on the likelihood of patients with rheumatoid arthritis (RA) developing septic arthritis (SA). METHODS: The United Kingdom General Practice Research Database (GPRD) was used to identify adults with RA, and age-, sex-, and practice-matched control subjects. Subjects were studied between 1987 and 2002. The risk of developing SA (excluding infected joint replacements) for individuals with RA was calculated and the effect of DMARD use determined. RESULTS: A total of 136,977 subjects (34,250 patients with RA, 102,747 controls) were identified. SA was identified in 345 subjects, of which 321 (236 in patients with RA, 85 in controls) cases occurred during the study period. The incidence rate of SA was 12.9 times higher in subjects with RA than in those without (95% confidence interval [95% CI] 10.1-16.5, P < 0.001). The incident rate ratios (IRRs) for developing SA while receiving DMARDs compared with receiving no DMARDs were different for different medications. Penicillamine (adjusted IRR 2.51, 95% CI 1.29-4.89, P = 0.004), sulfasalazine (adjusted IRR 1.74, 95% CI 1.04-2.91, P = 0.03), and prednisolone (adjusted IRR 2.94, 95% CI 1.93-4.46, P < 0.001) were associated with an increased incidence of SA when compared with not receiving any DMARD. The use of other DMARDs including methotrexate showed no such effect. CONCLUSION: Individuals with RA have an increased risk of developing SA. This increased risk can be attributed to both the disease process and the use of DMARDs.

van Staa TP, Geusens P, Bijlsma JW, Leufkens HG, Cooper C. · MRC Epidemiology Resource Centre, University of Southampton, Southampton, UK. · Arthritis Rheum. · Pubmed #17009229 links to  free full text

Abstract: OBJECTIVE: To determine whether patients with rheumatoid arthritis (RA) have an increased risk of fracture, and to estimate their long-term absolute fracture risk. METHODS: We studied patients with RA ages >or=40 years in the British General Practice Research Database, each matched by age, sex, calendar time, and practice to 3 control patients. Incident fractures, as recorded in the computerized medical records, were ascertained over a median followup of 7.6 years. The fracture rate in RA patients compared with controls was adjusted for smoking, body mass index (BMI), and several clinical risk factors, and Cox proportional hazards models were used to calculate the relative risk (RR) of fracture in RA. A risk score was then developed to provide an estimate of the 5- and 10-year fracture risk among RA patients. RESULTS: There were 30,262 patients with RA, of whom 2,460 experienced a fracture during followup. Compared with controls, patients with RA had an increased risk of fracture, which was most marked at the hip (RR 2.0, 95% confidence interval [95% CI] 1.8-2.3) and spine (RR 2.4, 95% CI 2.0-2.8). Indicators of a substantially elevated risk of fracture (at the hip) included >10 years' duration of RA (RR 3.4, 95% CI 3.0-3.9), low BMI (RR 3.9, 95% CI 3.1-4.9), and use of oral glucocorticoids (RR 3.4, 95% CI 3.0-4.0). Modeling of the long-term risk profiles revealed that, for example, in a woman age 65 years with longstanding RA whose risk factors also included low BMI, a history of fracture, and frequent use of oral glucocorticoids, the 5-year risk of hip fracture was 5.7% (95% CI 5.3-6.1%). CONCLUSION: Patients with RA are at increased risk of osteoporotic fractures. This increased risk is attributable to a combination of disease activity and use of oral glucocorticoids.

van Staa TP, Geusens P, Zhang B, Leufkens HG, Boonen A, Cooper C. · Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands. · Rheumatology (Oxford). · Pubmed #16899499 links to  free full text

Abstract: OBJECTIVES: There are few data on the cost-effectiveness of bisphosphonates with oral glucocorticoids (GCs). An individual patient-based pharmaco-economic model was developed. METHODS: Data were obtained from a cohort of oral GC users aged 40+ (n = 190 000) in the UK General Practice Research Database. Individualized fracture and mortality risks were calculated specific for age, sex, daily and cumulative GC dose, indication and other clinical risk factors. UK costs of medication and direct costs of fracture were obtained from National Institute for Clinical Excellence and used to estimate costs per quality-adjusted life-year (QALY) gained and fracture prevented for bisphosphonates in patients treated for 5 yrs with GCs. RESULTS: With the use of 5 mg GCs daily, the cost per one QALY gained with bisphosphonates was 41k UK pounds (95% confidence intervals 22-72k) in women aged <60 [men 40k pounds (29-54k)], 17k pounds (13-24k) in women aged 60-79 [men 43k pounds (31-60k)], 5k pounds(3-6k) in women aged 80+ [men 35k pounds (25-46k)]. With 15 mg GC, these figures were 17k pounds (14-21k), 13k pounds (10-16k) and 15k pounds (9-26k) in women and 22k pounds (17-26k), 34 pounds (23-53k) and 33k pounds (27-42k) in men, respectively. When stratifying by overall fracture risk and life expectancy at the start of GC therapy, cost per QALY increased with decreasing life expectancy. Patients with rheumatoid arthritis had comparatively better cost-effectiveness, given higher fracture risk and better life expectancy. CONCLUSIONS: The cost-effectiveness of bisphosphonates varied substantially. Bisphosphonates can be considered cost-effective in patients with higher fracture risks, such as elderly patients (with a life expectancy over 5 yrs), and younger patients with a fracture history, low body mass index, rheumatoid arthritis or using high GC doses.