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Jean-Marie Berthelot

Publications and source records attributed to Jean-Marie Berthelot.

At least 19 recordsLinked to original sources

Deriving utility scores for co-morbid conditions: a test of the multiplicative model for combining individual condition scores.

BACKGROUND: The co-morbidity of health conditions is becoming a significant health issue, particularly as populations age, and presents important methodological challenges for population health research. For example, the calculation of summary measures of population health (SMPH) can be compromised if co-morbidity is not taken into account. One popular co-morbidity adjustment used in SMPH computations relies on a straightforward multiplicative combination of the severity weights for the individual conditions involved. While the convenience and simplicity of the multiplicative model are attractive, its appropriateness has yet to be formally tested. The primary objective of the current study was therefore to examine the empirical evidence in support of this approach. METHODS: The present study drew on information on the prevalence of chronic conditions and a utility-based measure of health-related quality of life (HRQoL), namely the Health Utilities Index Mark 3 (HUI3), available from Cycle 1.1 of the Canadian Community Health Survey (CCHS; 2000-01). Average HUI3 scores were computed for both single and co-morbid conditions, and were also purified by statistically removing the loss of functional health due to health problems other than the chronic conditions reported. The co-morbidity rule was specified as a multiplicative combination of the purified average observed HUI3 utility scores for the individual conditions involved, with the addition of a synergy coefficient s for capturing any interaction between the conditions not explained by the product of their utilities. The fit of the model to the purified average observed utilities for the co-morbid conditions was optimized using ordinary least squares regression to estimate s. Replicability of the results was assessed by applying the method to triple co-morbidities from the CCHS cycle 1.1 database, as well as to double and triple co-morbidities from cycle 2.1 of the CCHS (2003-04). RESULTS: Model fit was optimized at s = .99 (i.e., essentially a straightforward multiplicative model). These results were closely replicated with triple co-morbidities reported on CCHS 2000-01, as well as with double and triple co-morbidities reported on CCHS 2003-04. CONCLUSION: The findings support the simple multiplicative model for computing utilities for co-morbid conditions from the utilities for the individual conditions involved. Future work using a wider variety of conditions and data sources could serve to further evaluate and refine the approach.

Journal Article↗

Current management of reflex sympathetic dystrophy syndrome (complex regional pain syndrome type I).

Although no major advances have occurred in the curative treatment of reflex sympathetic dystrophy syndrome (RSDS), new pathogenic insights may soon lead to innovative approaches, which may also prove effective in alleviating some forms of neuropathic pain. Preventing nerve compression and ischemia-reperfusion injury constitute valuable measures for preventing RSDS. Vitamin C administration can also prevent RSDS, together with clonidine in high-risk patients. Short-term glucocorticoid therapy has been found effective in preventing RSDS after stroke but has not been evaluated in other situations. Beneficial effects of bisphosphonates have been documented in several placebo-controlled trials. Placebo-controlled trials of ketamine and spinal cord stimulation are in order to confirm or refute the promising results obtained in open-label studies. Mirror visual feedback was introduced recently for the rehabilitation of patients with RSDS but needs to be evaluated in randomized controlled trials.

Analgesics↗

Gluteus tendon rupture is underrecognized by French orthopedic surgeons: results of a mail survey.

OBJECTIVES: To obtain information on the diagnosis and surgical treatment of hip rotator cuff tears by French orthopedic surgeons. METHODS: Survey conducted in 2003 by mailing questionnaires to 459 orthopedic surgeons practicing in France. RESULTS: Of the 84 respondents, 38 (45%) were not aware that tears could occur in the hip rotator cuff and 11 (13%) had never suspected this diagnosis in any of their patients. The 35 (42%) remaining surgeons had experience with at least one case of gluteal tendon repair; among them, 24 (29%) made the diagnosis fortuitously during surgery for another reason (total hip arthroplasty). Only 11 (13%) surgeons had performed surgery to treat gluteal tendon tears that were diagnosed preoperatively (gluteus medius in 20 cases, gluteus maximus in six cases, and gluteus minimus in three cases; total, 29 cases). Of these 29 cases, only 14 were treated by surgical tendon repair (by six [7%] surgeons); the remaining repair procedures were done during total hip arthroplasty. The retrospective data collection procedure and absence of medium-term follow-up data preclude conclusions about the outcomes of surgical treatment. CONCLUSION: Gluteal tendon tears may be underrecognized by orthopedic surgeons in France, who may have limited experience with repairing these lesions. Autopsy and imaging studies have shown gluteal tendon tears in up to 10% of individuals older than 60 years.

Buttocks↗

Provocative sacroiliac joint maneuvers and sacroiliac joint block are unreliable for diagnosing sacroiliac joint pain.

Mapping studies of pain elicited by injections into the sacroiliac joints (SIJs) suggest that sacroiliac joint syndrome (SIJS) may manifest as low back pain, sciatica, or trochanteric pain. Neither patient-reported symptoms nor provocative SIJ maneuvers are sensitive or specific for SIJS when SIJ block is used as the diagnostic gold standard. This has led to increasing diagnostic use of SIJ block, a procedure in which an anesthetic is injected into the joint under arthrographic guidance. However, several arguments cast doubt on the validity of SIJ block as a diagnostic gold standard. Thus, the effects of two consecutive blocks are identical in only 60% of cases, and the anesthetic diffuses out of the joint in 61% of cases, often coming into contact with the sheaths of the adjacent nerve trunks or roots, including the lumbosacral trunk (which may contribute to pain in the groin or thigh) and the L5 and S1 nerve roots. These data partly explain the limited specificity of SIJ block for the diagnosis of SIJS and the discordance between the pain elicited by the arthrography injection and the response to the block. The limitations of provocative maneuvers and SIJ blocks may stem in part from a contribution of extraarticular ligaments to the genesis of pain believed to originate within the SIJs. These ligaments include the expansion of the iliolumbar ligaments, the dorsal and ventral sacroiliac ligaments, the sacrospinous ligaments, and the sacrotuberous ligaments (sacroiliac joint lato-sensu). They play a role in locking or in allowing motion of the SIJs. Glucocorticoids may diffuse better than anesthetics within these ligaments. Furthermore, joint fusion may result in ligament unloading.

Diagnosis, Differential↗

Obesity--a growing issue.

OBJECTIVES: This article, based on longitudinal data, follows a sample of people who were aged 20 to 56 in 1994/95 to determine the percentage who made the transition from normal to overweight, or from overweight to obese by 2002/03. Characteristics that increased the chances of overweight people becoming obese are examined. DATA SOURCES: The data are from five cycles of the National Population Health Survey, 1994/95 through 2002/03. ANALYTICAL TECHNIQUES: Cox proportional hazards modelling was used to identify variables associated with an increased or decreased risk of becoming obese; 1,937 men and 1,184 women who were overweight in 1994/95 were selected. MAIN RESULTS: Close to a third (32%) of people who were aged 20 to 56 and of normal weight in 1994/95 had become overweight by 2002/03. During the same period, almost a quarter of those who had been overweight in 1994/95 had become obese. Among people who were overweight, the risk of obesity was relatively high for younger men and members of low-income households. Overweight men who smoked or who had activity restrictions had a high risk of obesity. Physical activity helped women avoid obesity.

Adult↗

Estimating summary measures of health: a structured workbook approach.

BACKGROUND: Summary measures of health that combine mortality and morbidity into a single indicator are being estimated in the Canadian context for approximately 200 diseases and conditions. To manage the large amount of data and calculations for this many diseases, we have developed a structured workbook system with easy to use tools. We expect this system will be attractive to researchers from other countries or regions of Canada who are interested in estimating the health-adjusted life years (HALYs) lost to premature mortality and year-equivalents lost to reduced functioning, as well as population attributable fractions (PAFs) associated with risk factors. This paper describes the workbook system using cancers as an example, and includes the entire system as a free, downloadable package. METHODS: The workbook system was developed in Excel and runs on a personal computer. It is a database system that stores data on population structure, mortality, incidence, distributions of cases entering a multitude of health states, durations of time spent in health states, preference scores that weight for severity, life table estimates of life expectancies, and risk factor prevalence and relative risks. The tools are Excel files with embedded macro programs. The main tool generates workbooks that estimate HALY, one per disease, by copying data from the database into a pre-defined template. Other tools summarize the HALY results across diseases for easy analysis. RESULTS: The downloadable zip file contains the database files initialized with Canadian data for cancers, the tools, templates and workbooks that estimate PAF and a user guide. The workbooks that estimate HALY are generated from the system at a rate of approximately one minute per disease. The resulting workbooks are self-contained and can be used directly to explore the details of a particular disease. Results can be discounted at different rates through simple parameter modification. CONCLUSION: The structured workbook approach offers researchers an efficient, easy to use, and easy to understand set of tools for estimating HALY and PAF summary measures for their country or region of interest.

Journal Article↗

[Algodystrophy].

Explore the source record for details and available documents.

Diagnosis, Differential↗

Tachon's syndrome (suracute back and/or thoracic pain following local injections of corticosteroids). A report of 318 French cases.

OBJECTIVES: To assess the frequency, features, and outcome of excruciating lumbar, dorsal, and/or thoracic pain following injections of local corticosteroids in rare instances. METHODS: A questionnaire mailed to 500 French rheumatologists. RESULTS: Three hundred and eighteen cases were reported by 92 rheumatologists (one event per 8000 injections or 6.5 years of practice), following injections into lumbar epidural space (39%), an upper limb (30%), a lower limb (mostly the heel) (24%), or other locations (7%), of cortivazol (67%), hydrocortisone (25%), betamethasone (7%), or paramethasone (1%). Symptoms occurred 1-5 min (78%) or less than 1 min (22%) after injection, and highly acute axial pain usually lasted for less than 5 min (34%) or 5-15 min (51%). In addition to pain in lumbar (84%) and/or dorsal regions (25%) [often preceded or associated with thoracic pain (36%)], other signs were: anxiety (87%), shortness of breath (64%), facial flushing (64%), diffuse sweating (41%), agitation (29%), transient cough (23%), abdominal pain (20%), transient hypertension (15%), paleness (10%), hypotension (8%), diarrhoea (3%) and headache (3%). None of these patients was known to be allergic, and urticaria developed in only 2%. Outcome was favourable in all cases (even though 4/318 patients were transiently hospitalised) with an overall duration of 25 +/- 71 min. Another injection was performed later in 146/318 cases (46%), but Tachon's syndrome recurred in only 20 of these 146 patients (14%). CONCLUSION: The outcome of this impressive syndrome seems excellent. Tachon's syndrome might be the venous counterpart of Nicolau's syndrome (injection of corticosteroids in an artery).

Adrenal Cortex Hormones↗

Suspected disk space infection with negative microbiological tests-report of eight cases and comparison with documented pyogenic discitis.

UNLABELLED: Few data are available on patients with suspected noniatrogenic pyogenic discitis but negative microbiological tests. OBJECTIVES: To compare the features, treatment, and outcomes in patients with suspected versus microbiologically documented noniatrogenic pyogenic discitis. PATIENTS: A retrospective chart review identified eight patients with suspected noniatrogenic pyogenic discitis managed at our institution over a 15-year period. Eighteen age- and sex-matched patients with microbiologically documented noniatrogenic pyogenic discitis managed at our institution during the same period served as controls. RESULTS: The eight cases had a longer time to diagnosis, a greater risk of abscess formation or epidural infection, and a smaller number of cutaneous portals of entry, as compared to the controls. None of the cases had evidence of endocarditis or diabetes mellitus. Infection at another site preceded the discitis in half the cases. Empirical treatment with two antimicrobials (usually a fluoroquinolone with a beta-lactam or fosfomycin) ensured a full recovery in all eight cases, with no relapses or long-term recurrences, whereas relapses occurred in three of the 18 controls treated with antibiotics selected by antibiotic susceptibility testing. CONCLUSION: Noniatrogenic pyogenic discitis with negative microbiological studies is associated with distinctive clinical features consistent with smoldering infection. The outcome is favorable under empirical two-drug antimicrobial therapy, usually including a fluoroquinolone given by the intravenous route.

Abscess↗

Cervical cancer mortality by neighbourhood income in urban Canada from 1971 to 1996.

BACKGROUND: The reduction of socioeconomic inequalities in health is an explicit objective of health policy in Canada, yet rates of death from cervical cancer are known to be higher among women of low socioeconomic status than among those of higher socioeconomic status. To evaluate progress toward the World Health Organization's goal of "Health for All," we examined whether income-related differentials in cervical cancer mortality diminished from 1971 to 1996. METHODS: Death registration data for Canada's census metropolitan areas in 1971, 1986, 1991 and 1996 were assigned to census tracts through postal code, and the tracts were in turn assigned to income quintiles based on their proportion of the population below the Statistics Canada low-income cutoff values. We compared age-standardized death rates (using the 1966 world population standard) in the female population (excluding those in institutions) across the 5 income quintiles and calculated interquintile rate ratios (poorest over richest) and interquintile rate differences (poorest minus richest). RESULTS: From 1971 to 1996, the overall age-standardized cervical cancer death rate per 100 000 women (and 95% confidence interval) declined from 5.0 (4.5-5.6) to 1.9 (1.7-2.1), the interquintile rate ratio diminished from 2.7 (1.8-4.2) to 1.7 (1.1- 2.6), and the interquintile rate difference decreased from 4.6 (2.8- 6.4) to 1.1 (0.2-1.9). INTERPRETATION: The income-related disparity in rates of death from cervical cancer as measured by rate ratios and rate differences diminished markedly in urban Canada from 1971 to 1996. Among the numerous factors that may have contributed to the decline (including decline in fertility and improvement in diet), one important factor was probably the implementation of effective screening programs.

Adult↗

Role for suppressor T cells in the pathogenesis of autoimmune diseases (including rheumatoid arthritis). Facts and hypotheses.

Although uncontrolled clones of autoreactive T cells play a central role in the pathogenesis of autoimmunity, another mechanism potentially involved in many autoimmune diseases is deficiency of suppressor T cells, most notably those belonging to the antiidiopeptide TH3/Tr1 TCD4+CD25+(high) subset. Failure of suppressor mechanisms may be in part primary, due to defective positive selection of suppressor T cells in the thymus, and in part acquired, secondary to chronic infections promoted by deficiencies in innate immunity. Renewed interest in suppressor TCD4+ cells has generated plausible explanations for many events including paradoxical induction of autoimmune disorders by immunosuppressive agents or thymectomy. Insights into the physiology of these regulatory T-cell clones might suggest new treatment options, although many currently used drugs (including anti-TNF alpha agents) enhance the activity of several suppressor T-cell clones. Investigation of these suppressor clones in rheumatoid arthritis is still in its infancy and faces obstacles such as the need for identifying key clones in each individual patient and the presence of T-cell repertoire contraction. This last phenomenon exists at disease onset and may stem from early thymus dysfunction, which may also lead to a reduction in suppressor TCD4+ cell counts. Thus, although restoring deficient suppressor clones may provide a full recovery in animals, the high prevalence of T-cell repertoire contraction in humans with rheumatoid arthritis may severely limit the beneficial effects of this therapeutic approach.

Animals↗

Patient knowledge of their disease: a French multicenter study in ankylosing spondylitis.

OBJECTIVES: To assess knowledge of ankylosing spondylitis (AS) by patients and to identify factors associated with knowledge. METHODS: Ninety patients receiving follow-up in France for AS completed a disease knowledge auto-questionnaire yielding a correct answer score [CAS] and a correct item score [CIS]. Correlations between these scores and other factors were examined. RESULTS: Mean CAS was 16.4/25 (SD = 4.8) and mean CIS 7.3 +/- 3.1/14. Female gender, higher educational level, having read about AS, being aware of AS support groups, and having received longer tertiary-care hospital management were associated with better knowledge. In the multivariate analysis, only three factors were independently associated with the level of knowledge in this population: "reading about AS", "level of general education", and "awareness of an AS support group". CONCLUSION: Knowledge of AS by French patients was lower than previously reported in a British population. Although education should be offered to all AS patients, the need may be greater in those with limited formal schooling. Booklets on the disease and contact with patient groups seem to be useful tools for improving knowledge of the disease.

Adult↗

Premature mortality in health regions with high aboriginal populations.

OBJECTIVES: Potential years of life lost (PYLL) before age 75 in health regions with a relatively high proportion of Aboriginal residents is compared, by cause of death, with all other health regions. DATA SOURCES: The findings are based on mortality data for 1995 through 1997 from the Canadian Vital Statistics Database, and on population estimates for 1995, 1996 and 1997 at the health region level. ANALYTICAL TECHNIQUES: PYLL was calculated by age and sex for two groups of health regions: the 18 with a high proportion (19% or more) of Aboriginal residents and the remaining 120, which had smaller proportions of Aboriginal residents. PYLL rate differences and rate ratios were used to compare the two groups. MAIN RESULTS: The PYLL rate per 1,000 person-years at risk for all causes of death was about 50% greater in the high-Aboriginal health regions than in the other group. Almost 40% of total PYLL in high-Aboriginal health regions was attributable to injuries, notably, suicide and motor vehicles accidents.

Accidents, Traffic↗

Informing patients about serious side effects of drugs. A 2001 survey of 341 French rheumatologists.

OBJECTIVES: In May 2001, we surveyed French rheumatologists to determine how they inform their patients about serious side effects of drugs. RESULTS: Of the 600 rheumatologists invited to participate in the study, 341 completed and returned the questionnaire. Most respondents believed that full information on patients would become the rule (mean, 62.1 +/- 28.3, the items being scored on a 100-point scale where 0 was "not at all" and 100 "absolutely"). The answer to this item varied little across age groups. Respondents felt that patient information fell primarily on the physician, (78 +/- 23), followed by pharmaceutical companies (64 +/- 32) and pharmacists (46 +/- 33). The respondents believed that full information of patients about side effects would primarily benefit physicians (51 +/- 32), followed by pharmaceutical companies (43 +/- 30) and patients (38 +/- 28). The reaction of patients to information on drug-related risks was described as "always favorable" by 2% of the respondents and as "fairly often favorable" by 55%. Among respondents, 9% always gave information on serious side effects, 66% fairly often, and 4% never; 2% always communicated information on the approximate frequency of serious adverse events, 21% fairly often, and 33% never. Similarly, 3% of the respondents always warned their patients of lethal risks, 11% fairly often, and 44% never. When evaluated on a 100-point scale (0, not at all knowledgeable; 100, very knowledgeable), knowledge of serious side effects of drugs for musculoskeletal conditions was 73 +/- 23, whereas knowledge of the frequency of these effects was only 52 +/- 22. Eight percent of the respondents always recommended that patients read the package insert, 27% fairly often, and 32% never. Conversely, the possible adverse effects of not taking the treatment were always specified by 21% of the respondents and fairly often by 88%.

Adult↗

Search for correlation of CD8 T cell response to Epstein-Barr virus with clinical status in rheumatoid arthritis: a 15 month followup pilot study.

OBJECTIVE: To assess in a longitudinal 15 month followup study the CD8 T cell response to immunodominant Epstein-Barr virus (EBV) antigens of 17 patients with rheumatoid arthritis (RA); and to seek an association between these responses and both clinical activity/severity of RA and a qualitative PCR for EBV in peripheral blood. METHODS: At each patient's visit every 3 months: (1) RA activity was assessed for Disease Activity Score (DAS-28); (2) a qualitative PCR for EBV was performed; (3) CD8 T cell response to EBV epitopes was screened in peripheral blood, using an autopresentation assay of 13 EBV peptides previously identified as immunodominant targets in RA synovia. Activation of anti-EBV CD8 T cells was evaluated by measuring the release of tumor necrosis factor-a. RESULTS: The semiquantitative CD8 T cell response to EBV roughly paralleled RA clinical activity in only 4/17 patients. No clear association could be found between positive PCR for EBV (performed at least once in 10/17 patients) and RA activity/severity or fatigue. Reactivity was not qualitatively broader in samples where PCR for EBV proved positive, and most often focused on one or 2 EBV antigens. However, these antigens differed between patients, as did the magnitude of CD8 T cell response to immunodominant antigens at different timepoints for the same patient. CONCLUSION: The CD8 T cell response to EBV paralleled clinical activity in only 4/17 patients. Our pilot study does not support the hypothesis that this CD8 response contributes to RA activity/flares, although the quantitative variations in the pattern of this reactivity over time confirmed that control of EBV manifestations was difficult in most patients with RA.

Adult↗

Potential impact of population-based colorectal cancer screening in Canada.

Randomized controlled trials (RCT) have shown the efficacy of screening for colorectal cancer (CRC) using the faecal occult blood test (FOBT) with follow-up by colonoscopy. We evaluated the potential impact of population-based screening by FOBT followed by colonoscopy in Canada: mortality reduction, cost-effectiveness, and resource requirements. The microsimulation model POHEM was adapted to simulate CRC screening using Canadian data and RCT results about test sensitivity and specificity, participation, incidence, staging, progression, mortality and direct health care costs. In Canada, biennial screening of 67% of individuals aged 50-74 in the year 2000 resulted in an estimated 10-year CRC mortality reduction of 16.7%. The life expectancy of the cohort increased by 15 days on average and the demand for colonoscopy rose by 15% in the first year. The estimated cost of screening was $112 million per year or $11,907 per life-year gained (discounted at 5%). Potential effectiveness would depend on reaching target participation rates and finding resources to meet the demand for FOBT and colonoscopy. This work was conducted in support of the National Committee on Colorectal Cancer Screening.

Aged↗