The longitudinal relationship between hand, hip and knee osteoarthritis and cardiovascular events: a population-based cohort study.

OBJECTIVE: In this population-based cohort study, we examined the association between the presence of symptomatic osteoarthritis (OA) and risk for cardiovascular (CV) events. METHOD: A cohort aged ≥55 years recruited from 1996 to 98 was followed through provincial health administrative data to 2014. Demographics, joint complaints and functional limitations were collected. Hip, knee and hand OA were defined using a validated definition. Using Cox-regressions, the relationship between OA and a composite CV outcome (myocardial infarction (MI), stroke, angina, heart failure, revascularization) was assessed controlling for age, body mass index (BMI), sex, pre-existing metabolic factors, comorbidities, income status, primary care exposure and functional limitations. RESULTS: 18,490 participants were included: median age was 68 years, 60.3% were female; 24.4% met criteria for OA (10.0% hip, 15.3% knee, 16.0% hand), 16.3% self-reported limitation in grip and 25.4% in walking. Over a median 13.4 years, 31.9% experienced a CV event. Controlling for all but walking limitation, a dose-response relationship was observed between number of joints affected by knee/hip OA and CV risk (HR 2 hips/knees vs none: 1.13, 95% CI 1.03-1.23; 3+ hips/knees: 1.22, 95% CI 1.09-1.36). This relationship became non-significant additionally controlling for difficulty walking. Self-reported difficulty walking was associated with a 30% increased hazard for CV events. The effect of hand OA was not significant. CONCLUSION: In a large population cohort, a greater burden of hip/knee OA was associated with higher CV risk; the relationship was explained by OA-related difficulty walking. Increased attention to management of OA with a view to improving mobility has potential to reduce CV events.

Osteoarthritis-related difficulty walking and risk for diabetes complications.

OBJECTIVES: To examine the effect of Osteoarthritis (OA)-related difficulty walking on risk for diabetes complications in persons with diabetes and OA. DESIGN: A population cohort aged 55+ years with symptomatic hip and knee OA was recruited 1996-98 and followed through provincial administrative data to 2015 (n = 2,225). In those with confirmed OA (examination and radiographs) and self-reported diabetes at baseline (n = 359), multivariate Cox regression modeling was used to examine the relationship between baseline difficulty walking (Health Assessment Questionnaire (HAQ) difficulty walking score; use of walking aid) and time to first diabetes-specific complication (hospitalization for hypo- or hyperglycemia, infection, amputation, retinopathy, or initiation of chronic renal dialysis) and cardiovascular (CV) events. RESULTS: Participants' mean baseline age was 71.4 years; 66.9% were female, 77.7% had hypertension, 54.0% had pre-existing CV disease, 42.9% were obese and 15.3% were smokers. Median HAQ difficulty walking score was 2/3 indicating moderate to severe walking disability; 54.9% used a walking aid. Over a median 6.1 years, 184 (51.3%) experienced one or more diabetes-specific complications; 191 (53.2%) experienced a CV event over a median 5.7 years. Greater baseline difficulty walking was associated with shorter time to the first diabetes-specific complication (adjusted HR per unit increase in HAQ walking 1.24, 95% CI 1.04-1.47, P = 0.02) and CV event (adjusted HR for those using a walking aid 1.35, 95% CI 1.00-1.83, P = 0.04). CONCLUSIONS: In a population cohort with OA and diabetes, OA-related difficulty walking was a significant - and potentially modifiable - risk factor for diabetes complications.

The Impact of Compliance with Imaging Follow-up on Mortality After Endovascular Abdominal Aortic Aneurysm Repair: A Population Based Cohort Study.

OBJECTIVE: Compliance with regular imaging follow-up after endovascular aortic aneurysm repair (EVAR) is inconsistent, and evidence of benefit from scheduled long-term surveillance is limited. This study sought to characterize the association between post-EVAR imaging frequency and long-term survival. METHODS: Using administrative health databases for the province of Ontario, Canada, a cohort of patients was identified who underwent EVAR between 2004 and 2014. Minimum appropriate imaging follow-up (MAIFU) was defined as a CT scan or ultrasound of the abdomen within 90 days of EVAR as well as every 15 months thereafter. Multivariate time to event analyses characterized the association between compliance with MAIFU over time and all-cause mortality. RESULTS: 4988 patients treated by EVAR were identified. Median follow-up was 3.4 years (IQR 2.0-5.3 years) and 90 day mortality was 1.6%. Among those who survived over 90 days, 87% (N = 4251 of 4902) underwent at least one CT scan or ultrasound of the abdomen within 90 days, but only 58% (N = 2859 of 4902) went on to meet MAIFU criteria. Infrequent imaging correlated with lower follow-up by a vascular surgeon, but not with infrequent primary care or specialist consultations. Consistently meeting MAIFU criteria was associated with a lower risk of death when compared with missing the first imaging follow-up within 90 days (HR 0.82, 95% CI 0.69-0.96, p = .014), or when compared with having first imaging follow-up within 90 days but subsequently not meeting MAIFU criteria (HR 0.78, 95% CI 0.68-0.91, p = .001). A larger proportion of the follow-up period meeting MAIFU criteria was associated with a lower risk of death. CONCLUSIONS: These data support efforts to improve compliance with imaging surveillance after EVAR.

Primary care physicians' perceptions about and confidence in deciding which patients to refer for total joint arthroplasty of the hip and knee.

OBJECTIVE: The purpose of this study is to examine the perceptions of primary care physicians (PCPs) regarding indications, contraindications, risks and benefits of total joint arthroplasty (TJA) and their confidence in selecting patients for referral for TJA. DESIGN: PCPs recruited from among those providing care to participants in an established community cohort with hip or knee osteoarthritis (OA). Self-completed questionnaires were used to collect demographic and practice characteristics and perceptions about TJA. Confidence in referring appropriate patients for TJA was measured on a scale from 1 to 10; respondents scoring in the lowest tertile were considered to have 'low confidence'. Descriptive analyses were conducted and multiple logistic regression was used to determine key predictors of low confidence. RESULTS: 212 PCPs participated (58% response rate) (65% aged 50+ years, 45% female, 77% >15 years of practice). Perceptions about TJA were highly variable but on average, PCPs perceived that a typical surgical candidate would have moderate pain and disability, identified few absolute contraindications to TJA, and overestimated both the effectiveness and risks of TJA. On average, PCPs indicated moderate confidence in deciding who to refer. Independent predictors of low confidence were female physicians (OR = 2.18, 95% confidence interval (CI): 1.06-4.46) and reporting a 'lack of clarity about surgical indications' (OR = 3.54, 95% CI: 1.87-6.66). CONCLUSIONS: Variability in perceptions and lack of clarity about surgical indications underscore the need for decision support tools to inform PCP - patient decision making regarding referral for TJA.

Comparative trends in incident fracture rates for all long-term care and community-dwelling seniors in Ontario, Canada, 2002-2012.

SUMMARY: In this population-based study, we compared incident fracture rates in long-term care (LTC) versus community seniors between 2002 and 2012. Hip fracture rates declined more rapidly in LTC than in the community. An excess burden of fractures occurred in LTC for hip, pelvis, and humerus fractures in men and hip fractures only in women. INTRODUCTION: This study compares trends in incident fracture rates between long-term care (LTC) and community-dwelling seniors ≥65 years, 2002-2012. METHODS: This is a population-based cohort study using administrative data. Measurements were age/sex-adjusted incident fracture rates and rate ratios (RR) and annual percent change (APC). RESULTS: Over 11 years, hip fracture rates had a marked decline occurring more rapidly in LTC (APC, -3.49 (95% confidence interval (CI), -3.97, -3.01)) compared with the community (APC, -2.93 (95% CI, -3.28, -2.57); p < 0.05 for difference in slopes). Humerus and wrist fracture rates decreased; however, an opposite trend occurred for pelvis and spine fractures with rates increasing over time in both cohorts (all APCs, p < 0.05). In 2012, incident hip fracture rates were higher in LTC than the community (RRs: women, 1.55 (95% CI, 1.45, 1.67); men, 2.18 (95% CI, 1.93, 2.47)). Higher rates of pelvis (RR, 1.48 (95% CI, 1.22, 1.80)) and humerus (RR, 1.40 (95% CI, 1.07, 1.84)) fractures were observed in LTC men, not women. In women, wrist (RR, 0.76 (95% CI, 0.71, 0.81)) and spine (RR, 0.52 (95% CI, 0.45, 0.61)) fracture rates were lower in LTC than the community; in men, spine (RR, 0.75 (95% CI, 0.57, 0.98) but not wrist fracture (RR, 0.91 (95% CI, 0.67, 1.23)) rates were significantly lower in LTC than the community. CONCLUSION: Previous studies in the community have shown declining hip fracture rates over time, also demonstrated in our study but at a more rapid rate in LTC. Rates of humerus and wrist fractures also declined. An excess burden of fractures in LTC occurred for hip fractures in women and for hip, pelvis, and humerus fractures in men.

γ-Glutamyl hydrolase modulation and folate influence chemosensitivity of cancer cells to 5-fluorouracil and methotrexate.

BACKGROUND: γ-Glutamyl hydrolase (GGH) regulates intracellular folate and antifolates for optimal nucleotide biosynthesis and antifolate-induced cytotoxicity, respectively. The modulation of GGH may therefore affect chemosensitivity of cancer cells, and exogenous folate levels may further modify this effect. METHODS: We generated a novel model of GGH modulation in human HCT116 and MDA-MB-435 cancer cells and investigated the effect of GGH modulation on chemosensitivity to 5-fluorouracil (5FU) and methotrexate (MTX) at different folate concentrations in vitro and in vivo. RESULTS: Overexpression of GGH significantly decreased chemosensitivity of MDA-MB-435 cells to 5FU and MTX at all folate concentrations as expected. In contrast, in HCT116 cells this predicted effect was observed only at very high folate concentration, and as the folate concentration decreased this effect became null or paradoxically increased. This in vitro observation was confirmed in vivo. Inhibition of GGH significantly increased chemosensitivity of both cancer cells to 5FU at all folate concentrations. Unexpectedly, GGH inhibition significantly decreased chemosensitivity of both cancer cells to MTX at all folate concentrations. In both GGH modulation systems and cell lines, the magnitude of chemosensitivity effect incrementally increased as folate concentration increased. CONCLUSION: Modulation of GGH affects chemosensitivity of cancer cells to 5FU and MTX, and exogenous folate levels can further modify the effects.

Exclusion of patients with sequential primary total joint arthroplasties from arthroplasty outcome studies biases outcome estimates: a retrospective cohort study.

OBJECTIVE: Total joint arthroplasty (TJA) outcome studies have largely focused on recipients of a single primary TJA, which may bias outcome estimates. DESIGN: This retrospective cohort study utilized health administrative databases from Ontario, Canada, to assemble a cohort that received a first primary elective hip or knee TJA for osteoarthritis (OA) between 2002 and 2009 (index TJA). Characteristics of TJA recipients at their index TJA were compared for those who did vs did not go on to receive one or more subsequent primary, elective hip/knee TJAs (multiple TJAs - yes/no) over a 2-year follow-up period. Cox proportional hazards, censored on death, was used to examine the relationship of receipt of multiple TJAs (yes/no) on rates of surgical complications for the index TJA, controlling for confounders. RESULTS: Among 97,374 eligible patients, 19,856 (20.4%) received a second primary elective TJA procedure within 2 years. In bivariate analyses, recipients of multiple primary TJAs were significantly more likely than single TJA recipients to be female, younger, with fewer co-morbidities (P < 0.0001), and to experience surgical complications with the index surgery, including early revision (P < 0.0001). Controlling for patient differences, receipt of >1 primary TJAs over 2 years was independently and significantly associated with lower odds of having experienced a surgical complication following the index arthroplasty (adjusted HR 0.65, 95%CI 0.59-0.72). CONCLUSIONS: One in five patients receiving their first elective primary hip or knee TJA received a second hip/knee TJA within 2 years. Our results indicate that exclusion of this large subsample of TJA recipients from TJA outcomes studies over-estimates surgical risks and may underestimate patient-reported benefits.

Continental variations in IgA nephropathy among Asians.

BACKGROUND/AIMS: Local variations in patient demographics and medical practice can contribute to differences in renal outcomes in patients with IgA nephropathy. We report the experiences of two groups of Asians with IgA nephropathy across continents. MATERIALS AND METHODS: We retrospectively examined two cohorts of Asian patients with IgA nephropathy from The King Chulalongkorn Memorial Hospital registry, Thailand (1994 - 2005), and The Metropolitan Toronto Glomerulonephritis registry, Canada (1975 - 2006), and compared their baseline characteristics. Slope of estimated glomerular filtration rate (eGFR) in each group was approximated using separate repeated measures regression models for each country. RESULTS: There were 152 Canadian and 76 Thai patients. At the time of first presentation, Thai patients were more likely to be female (63.2 vs. 44.1%, p = 0.01), have less baseline proteinuria (1.2 vs. 1.7 g/d, p = 0.08) and more likely to receive angiotensin-converting enzyme inhibitors (ACE-I) or angiotensin receptor blockers (ARB) (64.0 vs. 15.2%, p < 0.01), or prednisone (41.3 vs. 4.6%, p < 0.01). The annual change in estimated glomerular filtration rate (eGFR) for the Thai and Canadian groups were -0.82 ml/min/1.73 m2/year and -3.35 ml/min/1.73 m2/year, respectively, after adjustment for age, sex, mean arterial pressure (MAP), proteinuria, body mass index, Haas histological grade, chronicity scores and baseline medications. CONCLUSIONS: Although disease severity was similar among IgA nephropathy patients in Canada and Thailand, more Thai patients were on ACE-I/ARB or prednisone therapy at baseline. Further prospective research is needed to explore international differences in demographic and environmental factors, health resources, and disease management to determine how they may impact long-term outcomes in Asians with IgA nephropathy.

Hospital-acquired invasive group a streptococcal infections in Ontario, Canada, 1992-2000.

BACKGROUND: A significant proportion of invasive group A streptococcal infections are hospital acquired. No large, prospective studies have characterized this subgroup of cases and evaluated the risk of transmission in hospitals. METHODS: We conducted prospective, population-based surveillance of invasive group A streptococcal infections in Ontario, Canada, from 1992 to 2000. Epidemiologic and microbiologic investigations were conducted to identify cross-transmission. RESULTS: We identified 291 hospital-acquired cases (12.4%) among 2351 cases of invasive group A streptococcal disease. Hospital-acquired invasive group A streptococcal infections are heterogeneous, including surgical site (96 cases), postpartum (86 cases), and nonsurgical, nonobstetrical infections (109 cases). Surgical site infections affected 1 of 100,000 surgical procedures and involved all organ systems. Postpartum infections occurred at a rate of 0.7 cases per 10,000 live births and exhibited an excellent prognosis. Nonsurgical, nonobstetrical infections encompassed a broad range of infectious syndromes (case-fatality rate, 37%). Nine percent of cases were associated with in-hospital transmission. Transmission occurred from 3 of 142 patients with community-acquired cases of necrotizing fasciitis requiring intensive care unit (ICU) admission, compared with 1 of 367 patients with community-acquired cases without necrotizing fasciitis admitted to the ICU and 1 of 1551 patients with other cases (P<.001). Fifteen outbreaks were identified; 9 (60%) involved only 2 cases. Hospital staff were infected in 1 of 15 outbreaks, but colonized staff were identified in 6 (60%) of 10 investigations in which staff were screened. CONCLUSIONS: Presentation of hospital-associated invasive group A streptococcal infections is diverse. Cross-transmission is common; illness occurs in patients but rarely in staff. Isolation of new cases of necrotizing fasciitis and intervention after a single nosocomial case may also prevent transmission.

The economic cost of musculoskeletal disorders in Canada.

OBJECTIVE: This study estimated the total cost of musculoskeletal disorders for Canadians in 1994 and assessed the sensitivity of these cost estimates to variations in the definition of musculoskeletal disorders. METHODS: Disease-related costs, from a societal perspective, were measured using a prevalence-based analysis. First, direct treatment costs, including expenditures on hospitals and other institutions, physicians and other health professionals, drugs, research, and other items were assessed. Second, indirect costs associated with lost (or foregone) productivity due to disability and premature mortality were evaluated using the human capital approach. RESULTS: The total cost of musculoskeletal disorders in Canada was $25.6 billion (in 1994 Canadian dollars, $1.00 CDN approximately $0.75 US) or 3.4% of the gross domestic product. Direct and indirect costs were estimated at $7.5 billion and $18.1 billion, respectively. Lower and upper bound estimates of the total cost of musculoskeletal disorders, derived from the sensitivity analysis, were $19.9 billion and $30.8 billion, respectively. Wide variations were reported in the total cost of various musculoskeletal disorder subcategories, with the highest costs reported for injuries ($10.7 billion), back and spine disorders ($8.1 billion), and arthritis and rheumatism ($5.9 billion). CONCLUSIONS: The economic cost of musculoskeletal disorders was substantial and was sensitive to the definition of musculoskeletal disorders and other underlying assumptions. The hallmark of this study was the variation between subcategories in their cost, pattern of health resource use, and sequelae. The cost estimates may provide guidance in setting priorities for research and prevention activities.

Risk factors in elective laparoscopic cholecystectomy for conversion to open cholecystectomy.

BACKGROUND: Most cholecystectomies can be performed using a laparoscopic approach. However, 3 to 10 percent of laparoscopic cholecystectomies (LC) must be converted to open cholecystectomies (OC) and preoperative factors that predict risk for conversion are still not defined. STUDY DESIGN: Preoperative and intraoperative data were collected and analyzed from 628 patients who were scheduled for elective LC by two surgeons in an academic institution. Logistic regression was performed on data from two groups of patients: LC completed, 596 patients (95 percent) and LC converted, 32 patients (5 percent). RESULTS: Elective LC was accomplished with no common bile duct injuries, low morbidity rate (7.3 percent), and zero mortality rate. Both patient and surgeon factors predicted conversion from LC to OC. Older patients (65 years of age or older, (p < 0.01), males (p < 0.01), and patients with multiple attacks (ten or more) of biliary colic (p < 0.01), or a documented history of acute cholecystitis (p < 0.01) had a greater risk for conversion. Both surgeons had higher rates of conversion (p < 0.05) during the learning phase (fewer than 50 LC) of their experience. CONCLUSIONS: Risk factors for conversion may be predicted and awareness of these factors should help in the selection of the appropriate procedure for patients and in selection of cases for resident training.

Costs and outcomes associated with alternative discharge strategies following joint replacement surgery: analysis of an observational study using a propensity score.

We estimated the impact of alternative discharge strategies, following joint replacement (JR) surgery, on acute care readmission rates and the total cost of a continuum of care. Following surgery, patients were discharged to one of four destinations. Propensity scores were used to adjust costs and outcomes for potential bias in the assignment of discharge destinations. We demonstrated that the use of rehabilitation hospitals may lower readmission rates, but at a prohibitive incremental cost of each saved readmission, that patients discharged with home care had longer acute care stays than other patients, that the provision of home care services increased health system costs, and that acute care readmission rates were greatest among patients discharged with home care. Our study should be seen as one important stepping stone towards a full economic evaluation of the continuum of care for patients.

The effects of fee bundling on dental utilization.

OBJECTIVE: To examine dental utilization following an adjustment to the provincial fee schedule in which preventive maintenance (recall) services were bundled at lower fees. DATA SOURCES/STUDY SETTING: Blue Cross dental insurance claims for claimants associated with four major Ontario employers using a common insurance plan over the period 1987-1990. STUDY DESIGN: This before-and-after design analyzes the dental claims experience over a four-year period for 4,455 individuals 18 years of age and older one year prior to the bundling of services, one year concurrent with the change, and two years after the introduction of bundling. The dependent variable is the annual adjusted payment per user. DATA COLLECTION/EXTRACTION METHODS: The analysis was based on all claims submitted by adult users for services received at recall visits and who reported at least one visit of this type between 1987 and 1990. In these data, 26,177 services were provided by 1,214 dentists and represent 41 percent of all adult service claims submitted over the four years of observation. PRINCIPAL FINDINGS: Real per capita payment for adult recall services decreased by 0.3 percent in the year bundling was implemented (1988), but by the end of the study period such payments had increased 4.8 percent relative to pre-bundling levels. Multiple regression analysis assessed the role of patient and provider variables in the upward trend of per capita payments. The following variables were significant in explaining 37 percent of the variation in utilization over the period of observation: subscriber employment location; ever having received periodontal scaling or ever having received restorative services; regular user; dentist's school of graduation; and interactions involving year, service type, and regular user status. CONCLUSIONS: The volume and intensity of services received by adult patients increased when fee constraints were imposed on dentists. Future efforts to contain dental expenditures through fee schedule design will need to take this into consideration. Issues for future dental services research include provider billing practices, utilization among frequent attenders, and outcomes evaluation particularly with regard to periodontal care and replacement of restorations.

Familial segregation in the occurrence and severity of periampullary neoplasms in familial adenomatous polyposis.

BACKGROUND: Familial adenomatous polyposis (FAP) patients often develop periampullary adenomas that may progress to periampullary cancer, a common cause of death in this population. The risk of periampullary cancer in FAP is unclear, and variables that predict the occurrence and severity of periampullary tumors are not well understood. The specific aim of this study was to determine whether the risk of periampullary neoplasia segregates in specific FAP families. MATERIALS AND METHODS: A total of 144 FAP patients from 74 families were either screened by gastroduodenoscopy (n = 132) or information was obtained from surgical or autopsy reports (n = 12). The severity of periampullary neoplasia was recorded for each patient and graded based on maximum polyp size and histology. Linear regression was used to determine the significance of a number of variables with respect to periampullary neoplasia. A blood sample was available from at least one member of 50 unrelated families and used to detect germline mutations in codons 686 through 1693 of the adenomatous polyposis coli (APC) gene. RESULTS: Statistically significant familial segregation was found for the incidence and severity of periampullary neoplasia (P < 0.02). Age was also a statistically significant variable (P < 0.01). No correlation was observed between specific APC germline mutations and periampullary polyp frequency and severity. CONCLUSIONS: The occurrence and severity of periampullary neoplasms in patients with FAP segregates in families. This familial association may be related to as yet unidentified modifier genes or perhaps common environmental factors. These results should prove useful in developing upper gastrointestinal screening protocols for FAP patients at risk for periampullary neoplasia.

Rates of revision knee replacement in Ontario, Canada.

BACKGROUND: The present study was designed to measure the longevity of knee replacements and to assess the determinants of revision knee replacements in order to enhance the potential for informed decision-making. METHODS: Data on all hospitalizations for knee replacement that occurred in Ontario, Canada, between April 1, 1984, and March 31, 1991, were acquired. To calculate the rates of revision knee replacement, two algorithms were developed: one distinguished primary knee replacements from revision knee replacements, and the second linked revision knee replacements to primary knee replacements. The Kaplan-Meier method was used to assess survivorship (absence of a revision) for primary knee replacement. A proportional-hazards regression model was estimated to assess the role of independent variables on the survival of primary knee replacements. RESULTS: During the period of the study, 7.0 percent (1301) of 18,530 knee replacements were classified as revisions. Significant differences were identified between hospitalizations for primary and revision knee replacements in terms of the patient and hospital characteristics. Patients who were more than fifty-five years old, lived in a rural area, or had a diagnosis of rheumatoid arthritis had a significantly (p < 0.05) longer duration before revision than did other patients. Primary knee replacements performed in a teaching or specialty hospital had a significantly (p < 0.05) shorter duration before revision than did those performed in a non-teaching hospital. The long-term rates of revision were uniformly low. Estimates of the proportion of knee replacements that would need to be revised within seven years ranged from a low of 4.3 percent, with use of the algorithm for the longest time to revision, to a high of 8.0 percent, with use of the algorithm for the shortest time to revision. CONCLUSIONS: Revision of a primary knee replacement was a rare event that depended on a patient's age, gender, and place of residence as well as on the hospital where the primary knee replacement was performed. Estimates of the rates of revision knee replacement after almost seven years ranged from a low of 4.3 percent to a high of 8.0 percent.

Health-related quality of life after knee replacement.

A cross-sectional, community-based survey of a random sample of 1750 of 242,311 Medicare recipients was performed. The patients were at least sixty-five years old and had had a primary or revision knee replacement (either unilaterally or bilaterally) between 1985 and 1989. Three samples were surveyed separately: a national sample (to reflect the United States as a whole) and samples from Indiana and the western part of Pennsylvania (sites chosen for convenience to assess the validity of the findings for the national sample on a regional level). Each sample was stratified by race, age, residence (urban or rural), and the year of the procedure. Valid and reliable questionnaires were used to elicit the participants' assessments of pain, physical function, and satisfaction two to seven years after the knee replacement. Of the 1486 patients who were eligible for inclusion in the survey, 1193 (80.3 per cent) responded. The mean age of the respondents was 72.6 years. Eight hundred and forty-nine respondents (71.2 per cent) were white, and 849 (71.2 per cent) were women. The participants reported that they had little or no pain in the knee at the time of the survey, regardless of the age at the time of the knee replacement, the body-mass index, or the length of time since the knee replacement. After adjustment for potential confounding variables, predictors of better physical function after the replacement were an absence of problems with the contralateral knee, primary knee replacement (rather than revision) (Indiana sample only), and a lower body-mass index (Indiana and western Pennsylvania samples). Four hundred and fifteen (85.2 per cent) of the 487 patients in the national sample were satisfied with the result of the knee replacement. In what we believe to be the first community-based study of the outcome of knee replacement, patients reported having significant (p = 0.0001) and persistent relief of pain, improved physical function, and satisfaction with the result two to seven years postoperatively. The findings of the present study suggest that age and obesity do not have a negative impact on patient-relevant outcomes (pain and physical function). Dissemination of these findings has the potential to increase appropriate referrals for knee replacement and thereby reduce the pain and functional disability due to osteoarthrosis of the knee.

The economic burden of disabling hip and knee osteoarthritis (OA) from the perspective of individuals living with this condition.

OBJECTIVE: To estimate the direct and indirect arthritis-attributable costs to individuals with disabling hip and/or knee osteoarthritis (OA). METHODS: An established population cohort with disabling hip and/or knee OA from two regions of Ontario, Canada was surveyed to determine participant and caregiver costs related to OA, and the predictors of these costs. RESULTS: The response rate was 87.2%. Of 1378 respondents, 1258 had OA (mean age 73.1 yr, range 59-100). Sixty per cent (n = 758) reported OA-related costs. Among these individuals, the average annual cost was 12,200 dollars(CDN dollars in 2002, where 1.00 CDN dollar approximately 0.81 US dollar). Time lost from employment and leisure by participants and their unpaid caregivers accounted for 80% of the total. Men were less likely than women to report costs (adjusted odds ratio 0.54, P < 0.0001), but when they did their expenditures were significantly higher (P = 0.004). Greater disability was associated with higher costs: compared with individuals with WOMAC total scores <15, those with scores > or = 55 were 15 times more likely to report costs, and their costs were 3 times greater (both P < 0.0001). Both the young (<65 yr) and very old were more likely to incur costs (P < 0.0001), and when they did their costs were higher (P < 0.001). CONCLUSION: Costs incurred were mainly for time lost from employment and leisure, and for unpaid informal caregivers. Failure to value such indirect costs significantly underestimates the true burden of OA. Costs increased with worsening health status and greater OA severity. After adjustment, men were less likely to incur costs, possibly due to greater social resources.

Socio-economic status and surgery in children: myringotomies and tonsillectomies in Ontario, Canada, 1996-2000.

AIM: To examine the relation between socio-economic status and (1) receipt of paediatric otolaryngological surgery, and (2) inclusion of adjuvant procedures. METHODS: Using data on myringotomies with insertion of tympanostomy tube and tonsillectomies for all children in Ontario, Canada, from 1996 to 2000, and census data on socio-economic status, we examined the association between socio-economic status and (1) the probability of surgery (myringotomy or tonsillectomy), and (2) the probability that surgery was accompanied by an adjuvant procedure. RESULTS: Lower socio-economic status was associated with increased likelihood that a child's initial surgery was a tonsillectomy rather than a myringotomy (odds ratio per unit increase in the deprivation index = 1.09, p = 0.01, confidence interval 1.06-1.11), and with increased likelihood that those children having a myringotomy would undergo a tonsillectomy during the same hospitalization (odds ratio 1.14, p < 0.0001, confidence interval 1.11-1.16). Children from neighbourhoods with larger immigrant populations were less likely to receive either procedure (odds ratios per 1% increase in the proportion of immigrants = 0.97 (p < 0.0001, confidence interval 0.96-0.97) for myringotomies and 0.97 (p < 0.0001, confidence interval 0.97-0.98) for tonsillectomies). CONCLUSIONS: Socio-economic status was associated with treatment selection for the two most common paediatric surgical procedures. Further research should examine whether differences in treatment arise at the level of the primary care physician, the specialist, and/or are due to parental preference.

Referral of children with otitis media. Do family physicians and pediatricians agree?

OBJECTIVE: To determine factors influencing family physicians' and pediatricians' decisions to refer children with recurrent acute otitis media (RAOM) and otitis media with effusion (OME) to otolaryngologists for an opinion about tympanostomy tube insertion. DESIGN: Mailed survey. SETTING: Physicians' practices in Ontario. PARTICIPANTS: Random sample of 1459 family physicians and all 775 pediatricians in the province. MAIN OUTCOME MEASURES: Physicians' reports of the influence of 17 factors on decisions to refer (more likely, no influence, less likely to refer) and number of episodes of otitis media, months with effusion, level of hearing loss, or months of continuous antibiotics without improvement prompting referral. RESULTS: Physicians agreed (> 80% concordance) on six out of 17 factors as indications for referring children with RAOM or OME. Opinions about the importance of other factors varied widely. Family physicians would refer children with otitis media after fewer episodes of illness, fewer months of effusion, lower levels of hearing loss, and fewer months of prophylactic antibiotic therapy than pediatricians (all P < .001). Pediatricians would prescribe continuous antibiotics longer (11.8 weeks) than family physicians (8.9 weeks, P < .0001), which correlated with lower referral thresholds for family physicians. CONCLUSION: Family physicians' and pediatricians' self-reported referral practices for surgical opinions on children with otitis media varied considerably. These observations raise questions about the consistency of care for children with otitis media and whether revised clinical guidelines would be helpful.

Opiate-seeking behavior under conditions of methadone detoxification and removal.

This study was carried out to determine whether heroin-dependent persons, having completed methadone detoxification, can be maintained on an inert substance which has previously been associated with methadone. Forty heroin-dependent men and women were randomly allocated to either a "standard detoxification" group or a cordial substitution group. Results showed that subjects administered methadone-associated cordial after methadone detoxification could not be retained at the clinic for a time significantly beyond that of subjects in the standard detoxification group despite the inability of the subjects to accurately estimate methadone dosage. The role of cognitive factors is discussed.