Two knees or not two knees? Patient costs and outcomes following bilateral and unilateral total knee joint replacement surgery for OA.

AIMS: This study aims to address medical and non-medical direct costs and health outcomes of bilateral and unilateral total knee replacement from the patients' perspective during the first year post-surgery. METHODS: Osteoarthritis patients undergoing primary unilateral total knee or bilateral total knee replacement (TKR) surgery at three Sydney hospitals were eligible. Patients completed questionnaires pre-operatively to record expenses during the previous three months and health status immediately prior to surgery. Patients then maintained detailed prospective cost diaries and completed SF-36 and WOMAC Index each three months for the first post-operative year. RESULTS: Pre-operatively, no significant differences in health status were found between patients undergoing unilateral TKR and bilateral TKR. Both unilateral and bilateral TKR patients showed improvements in pain, stiffness and function from pre-surgery to 12 months post-surgery. Patients who had bilateral TKR spent an average of 12.3 days in acute hospital and patients who had unilateral TKR 13.6 days. Totally uncemented prostheses were used in 6% of unilateral replacements and 48% of bilateral replacements. In hospital, patients who had bilateral TKR experienced significantly more complications, mainly thromboembolic, than patients who had unilateral TKR. Regression analysis showed that for every one point increase in the pre-operative SF-36 physical score (i.e. improving physical status) out-of-pocket costs decreased by 94%. Out-of-pocket costs for female patients were 3.3 times greater than for males. CONCLUSION: Patients undergoing bilateral TKR and unilateral TKR had a similar length of stay in hospital and similar out-of-pocket expenditures. Bilateral replacement patients reported better physical function and general health with fewer health care visits one year post procedure. Patients requiring bilateral TKR have some additional information to aid their decision making. While their risk of peri-operative complications is higher, they have an excellent chance of good health outcomes at 12 months and are not going to be doubly "out-of-pocket" for the experience.

Living with rheumatoid arthritis: expenditures, health status, and social impact on patients.

OBJECTIVE: To determine costs related to living with rheumatoid arthritis (RA), and to identify the association between health status-as measured by the Health Status Questionnaire short form-36 (SF-36) and the disease specific index Health Assessment Questionnaire (HAQ)-and the social impact of RA. METHODS: A prospective cohort study was carried out on 81 patients with RA who completed four consecutive three month cost diaries. The SF-36, HAQ, and social impact at baseline and one year follow up were also assessed. RESULTS: Women reported worse SF-36 physical function and HAQ scores than men and received more assistance from family and friends. Women spent more on non-prescription medication and devices to assist them than men. Older patients had higher expenditure on visits to health professionals, whereas younger patients spent more on prescription medication and tests. Pension status and membership of private health insurance schemes were important determinants in these differences in expenditure. CONCLUSION: Costs increased with duration of disease, those with private health insurance had greater out of pocket costs (excluding membership fees), and those with pension support had fewer costs. Women were more affected by RA than men in health status, social impact, and out of pocket costs.

Living with osteoarthritis: patient expenditures, health status, and social impact.

OBJECTIVE: To determine "out-of-pocket" expenditures related to osteoarthritis (OA) and to explore whether demographic details, health status scores (Medical Outcomes Study 36-item Short Form [SF-36] and Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC]), or perception of social effect were expenditure determinants. METHODS: A prospective cohort study of community-dwelling subjects with OA completed 4 consecutive 3-month cost diaries. In addition, subjects completed the SF-36 and WOMAC at baseline and at 12 months. Social impact at baseline was collected. Four groups categorized by age and sex were compared. Patients undergoing joint replacement were excluded. RESULTS: Differences in health status were defined more by age than by sex, especially for physical function. The costs to the patients were high, particularly for women, who spent more on medications and special equipment. Women also reported receiving more assistance from family and friends. Higher disease-related expenditures were associated with greater pain levels, poorer social function and mental health, and longer duration of disease. Significant independent predictors of total patient expenditures related to OA were being female and having joint stiffness. CONCLUSION: Despite having heavily subsidized health care and access to the Pharmaceutical Benefits Scheme, out-of-pocket costs for patients with OA in Australia are considerable. Higher expenditures for patients with OA are related to more advanced disease, especially for women.

A comparison of outcomes in osteoarthritis patients undergoing total hip and knee replacement surgery.

OBJECTIVE: The aims of this study were to assess changes in physical function and quality of life with the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the instrument of the Medical Outcomes Study SF-36 Health Survey (MOS SF-36), respectively, in patients undergoing hip anf knee joint replacement surgery and to compare the responsiveness of these two outcome measures 1 year after surgery. DESIGN: One hundred and ninety-four patients with osteoarthritis (OA knee 108, OA hip 86) admitted to four hospitals in Sydney were followed over a period of 1 year at 3 monthly intervals. RESULTS: WOMAC measures improved significantly after 1 year for OA hip and OA knee: there was reduction in pain of 71% and 53%, reduction of stiffness of 55% and 43% and improvement in physical function of 68% and 43%, respectively. MOS SF-36 measures in those having hip surgery improved significantly for pain (222%), physical function (247%), physical role functioning (402%), general health (110%), vitality (143%0, social functioning (169%) and mental health (114%). For those in the knee surgery group, significant improvement was seen for pain (175%), physical function (197%), physical role functioning (275%), vitality (125%) and social functioning (119%). The WOMAC was a more responsive measure than the MOS SF-36. CONCLUSION: WOMAC and MOS SF-36 detect significant and clinically meaningful changes in outcome after hip and knee replacement. WOMAC requires a smaller sample size and is more responsive in the short term. For a follow-up longer than 6 months MOS SF-36 provides additional information. The improvement in outcomes following hip joint surgery were significantly greater than those following knee surgery.

Determinants of willingness to pay for hip and knee joint replacement surgery for osteoarthritis.

OBJECTIVES: To determine whether patients with osteoarthritis (OA) would be willing to pay for joint replacement and whether patient characteristics or health outcomes, including pain, physical function and health-related quality of life, were related to willingness to pay (WTP). METHODS: Patients who had undergone primary total hip replacement (THR) or total knee replacement (TKR) for OA completed a disease-specific questionnaire (Western Ontario and McMaster: WOMAC index), a generic measure of health status (Medical Outcome Study Short Form-36: SF-36) and an Evaluation Questionnaire to measure WTP and satisfaction with the replacement. RESULTS: Responses were obtained from 109 (77%) THR patients and 129 (72%) TKR patients. Mean age of respondents was 67 yr for THR (47% female) and 73 yr for TKR (60% female). Overall, 85% of patients responded to the WTP question. Of the THR patients, 71% were willing to pay something, 11% were not willing to pay anything and 18% did not answer the question. For TKR patients these figures were 70, 16 and 14% respectively. However, of those who responded to the WTP question, only 25% of the THR patients and 18% of the TKR patients indicated they would be willing to pay the actual current average cost of the operation in Australia (>/= A$15 000). A lower postoperative pain score (as measured by the WOMAC index) was a significant predictor of WTP for both THR and TKR patients. Income also significantly predicted WTP in THR patients but not in TKR patients. The other significant predictors for TKR patients were older age, having private health insurance and willingness to recommend joint replacement to others. CONCLUSIONS: Willingness to pay was a measure that was understandable and acceptable to patients, most of whom were willing to pay something. There was a high correlation between WTP, good health outcomes and patient satisfaction, pain relief being the dominant determinant.

Outcomes after hip or knee replacement surgery for osteoarthritis. A prospective cohort study comparing patients' quality of life before and after surgery with age-related population norms.

OBJECTIVE: To compare the health-related quality of life of people with osteoarthritis before and after primary total hip and knee replacement surgery with that of the general Australian population. DESIGN: A prospective cohort study. SETTING: Three Sydney hospitals, public and private. PARTICIPANTS: Patients with osteoarthritis undergoing primary total hip (n = 59) and knee (n = 92) joint replacement surgery. MAIN OUTCOME MEASURE: Medical Outcomes Study Short Form (SF-36) scores before and 12 months after joint replacement surgery (compared with population norms). RESULTS: Patients in each age group showed a significant improvement in health-related quality of life after joint replacement surgery in most scales of the SF-36, particularly physical function, role physical and bodily pain. SF-36 scores for the 42 hip-replacement patients aged 55-74 years improved to equal or exceed the population norm on all scales. SF-36 scores of the 52 knee replacement patients aged 55-74 years improved, but physical function and bodily pain scores remained significantly worse than the population norm. SF-36 scores for both hip (n = 17) and knee (n = 40) replacement patients aged 75 years and over improved significantly, becoming similar to population norms for this age group. CONCLUSIONS: Total hip or knee replacement for osteoarthritis significantly improves patient health and well-being at 12 months after surgery. Age alone should not be a barrier to surgery.