[Productivity costs of rheumatoid arthritis in Germany. Cost composition and prediction of main cost components]. / Produktivitätskosten der rheumatoiden Arthritis in Deutschland. Kostenzusammensetzung und Prädiktion der Hauptkostenkomponenten.

OBJECTIVE: Identification of predictors for the productivity cost components: (1) sick leave, and (2) work disability in gainfully employed and (3) impaired household productivity in unemployed patients with rheumatoid arthritis (RA) from the societal perspective. METHODS: Investigation of productivity costs was linked to a multicenter, randomized, controlled trial evaluating the effectiveness of clinical quality management in 338 patients with RA. The productivity losses were assessed according to the German Guidelines on Health Economic Evaluation. By means of multivariate logistic regression analyses, predictors of sick leave, work disability (employed patients, n=96), and for days confined to bed in unemployed patient (n=242) were determined. RESULTS: Mean annual costs of 970 EUR arose per person taking into consideration all patients (453 EUR sick leave, 63 EUR work disability, 454 EUR impaired productivity of unemployed patients). Disease activity, disease severity, and impaired physical function were global predictors for all of the cost components investigated. Sick leave costs were predicted by prior sick leave periods and the vocational status blue collar worker, work disability costs by sociodemographic variables (marital status, schooling), and the productivity costs of unemployed patients by impaired mental health and impaired physical functions. CONCLUSIONS: Interventions such as reduction in disease progression and control of disease activity, early vocational rehabilitation measures and vocational retraining in patients at risk of quitting working life, and self-management programs to learn coping strategies might decrease future RA-related productivity costs.

Implementing standardized cost categories within economic evaluations in musculoskeletal diseases.

We present a matrix of relevant resource utilization domains for use in standardizing applied cost assessment in musculoskeletal conditions. In addition,we highlight the importance of selecting cost categories during the development of an economic evaluation. A set of four steps was applied: (a) literature search identifying economic evaluations in osteoarthritis and osteoporosis, (b) listing and aggregation of cost categories mentioned in the identified articles, (c) development of a matrix of resource utilization domains, and (d) qualitative discussion regarding the generalizability of the matrix to other musculoskeletal conditions such as rheumatoid arthritis. We examined 41 full-length articles (25 cost-of-illness studies or cost-comparisons, 14 cost-effectiveness analyses, and 2 cost-utility analyses), of which 16 studies focused on osteoarthritis and 25 on osteoporosis. The reviewed studies used a total of 151 different cost categories which, after adjustment for synonymous labeling, made up 34 cost categories. A matrix of 16 separate resource utilization domains was developed including seven outpatient, three inpatient, four other disease-related, and two productivity cost domains. We found that cost assessment in economic evaluation in the key musculo-skeletal diseases (osteoarthritis, osteoporosis, and rheumatoid arthritis) is performed rather inhomogeneously. A generalized matrix of applicable resource utilization domains and a flowchart facilitating the development of appropriate resource utilization data have been developed.

Development of a matrix of cost domains in economic evaluation of rheumatoid arthritis.

The aim of our study was to comprehensively review and critically appraise the cost domains used in economic evaluations of the rheumatic diseases and to use this information to propose standardization of cost domains. The literature search identified 210 abstracts, 32 of which included original cost data. The listed cost categories were grouped into 3 major areas: (direct) health care costs, other (direct) disease related costs, and productivity costs (indirect costs). The number of individual cost categories was reduced by considering the following criteria: (1) inclusion of all relevant cost domains; (2) avoidance of double counting; (3) summarizing of related categories under one representative heading; (4) feasibility of level of aggregation. After adjustment for synonymous labeling, 38 cost categories remained. The subsequent development of a classification scheme of cost categories led to a set of 19 separate cost domains including 7 outpatient, 3 inpatient, 6 other disease related, and 3 productivity cost domains. This literature review indicates that cost assessment in economic evaluations in rheumatoid arthritis lacks standardization. A preliminary scheme to categorize cost assessment in rheumatic conditions is presented. The adoption of standards for economic evaluation would greatly facilitate national and international comparisons.

Cost assessment instrument in rheumatology: evaluation of applied instrument characteristics.

We compared the major characteristics of internationally applied cost assessment instruments (CAI) in rheumatic conditions. Fifteen utilization questionnaires were identified and assessed using a structured approach. The forms differed considerably with respect to applied characteristics: length (3-113 items), recall period (between 1 week and 1 year), format (2 interview, 13 self-administered), response categories, cost units (physical vs monetary), and cost domains covered. While all included a gross assessment of outpatient and inpatient costs, the level of disaggregation differed. Only a few CAI included an assessment of other direct disease related costs (e.g., home remodeling or home health care services) and out-of-pocket expenditure. Productivity costs were included in all but 2 CAI. Efforts to further standardize the applied CAI should (1) be based on sound psychometric data, (2) define a required core set of cost domains covered, (3) discriminate between generic and relevant disease related cost components, and (4) examine the feasibility of developing international standards for cost data.

Effects of a calcium entry blocker on blood pressure and renal function during angiotensin-induced hypertension.

The effects of the calcium entry blocker nitrendipine on blood pressure (BP) and renal hemodynamics were studied in rats with angiotensin II (ANG II)-induced hypertension. The ANG II was infused subcutaneously by implanted osmotic minipumps for 14 to 16 days. There was a progressive rise in BP in ANG II-infused rats to levels 58 mm Hg above basal by Day 10, whereas control rats with sham pumps remained normotensive. Nitrendipine or vehicle was administered by gavage to groups of control and hypertensive rats for 5 days, and clearance experiments were performed with the rats under anesthesia on the last day. The prolonged infusion of ANG II increased the renal vascular resistance and reduced the glomerular filtration rate and renal Na+ excretion. At a dose of 3 mg/100 g body weight, nitrendipine had no consistent effects on BP or renal function of control rats. By contrast, in rats with ANG II-induced hypertension, nitrendipine normalized both the BP and the changes in renal vascular resistance and glomerular filtration rate. Despite the fall in BP, nitrendipine caused a marked diuresis and natriuresis. Moreover, nitrendipine increased Na+ excretion of conscious, ANG II-hypertensive rats but not of controls. Thus, nitrendipine appears to be highly effective in reversing ANG II-induced hypertension and Na+ retention. These findings also indicate that the hypertension, renal vasoconstriction, and Na+ retention accompanying prolonged ANG II infusions may be mediated by calcium-dependent mechanisms.

Nitrendipine reverses vasoconstriction and renal hemodynamic changes in experimental hypertension.

Nitrendipine, a calcium entry blocker, was administered by gavage (3 mg/100 g body weight/day) to rats with prolonged angiotensin-II-(AII) induced hypertension. AII was infused by osmotic minipump implanted subcutaneously. Persistent hypertension was established after 5 days. Normotensive control rats had empty sham pumps. Nitrendipine, administered from day 11 to 15 after pump implantation, normalized blood pressure consistently in AII rats, whereas it had no significant hypotensive effect in controls. Renal clearance experiments in anesthetized rats revealed that nitrendipine reversed all noted abnormalities of AII-infused rats, including hypertension and reductions in glomerular filtration rate, renal blood flow, and urinary sodium excretion. When receiving nitrendipine, sham controls did not show significant changes in blood pressure, renal function, or natriuresis. The results demonstrate that oral administration of nitrendipine is highly effective in normalizing blood pressure during prolonged AII-induced hypertension. The antihypertensive effect is achieved by this calcium entry blocker's vasodilatory action, supported by a marked natriuretic effect. By contrast, blood pressure and renal function of normotensive control rats were not appreciably affected by oral nitrendipine.