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Biomedical subjects

M Harth

Publications and source records attributed to M Harth.

At least 37 records · Page 2Linked to original sources
PubMed1999

The London Fibromyalgia Epidemiology Study: direct health care costs of fibromyalgia syndrome in London, Canada.

OBJECTIVE: To estimate direct health care costs associated with fibromyalgia (FM) within a representative community sample. METHODS: A random sample of 3395 noninstitutionalized adults was screened for widespread pain. Individuals screening positive were examined for FM. Direct health care costs were compared among those with confirmed FM (FM cases, FC), those with widespread pain not having FM (pain controls, PC), controls without widespread pain (general controls, GC), and a random sample of age, sex and geographically matched controls from the Ontario Health Insurance Plan database (OHIP controls, OC). RESULTS: One hundred FC (86 women) were compared to 76 PC subjects, 135 GC, and 380 OC. FC used more medications and outpatient health services than PC subjects, and about twice the health services at twice the cost compared to GC and OC. The mean difference in direct costs for health services between FC and OC was $493 Cdn annually (p<0.001). CONCLUSION: FM has a major effect on direct health care costs.

Adult↗
PubMed1999

The London Fibromyalgia Epidemiology Study: the prevalence of fibromyalgia syndrome in London, Ontario.

OBJECTIVE: To estimate the point prevalence of fibromyalgia syndrome (FM) among noninstitutionalized Canadian adults; and to assess the effect of demographic variables on the odds of having FM. METHODS: A screening questionnaire was administered via telephone to a random community sample of 3395 noninstitutionalized adults residing in London, Ontario. Individuals screening positive were invited to be examined by a rheumatologist to confirm or exclude FM using the 1990 American College of Rheumatology classification criteria. RESULTS: One hundred confirmed cases of FM were identified, of whom 86 were women. Mean age among FM cases was 49.2 years among women, 39.3 years among men (p < 0.02). FM affects an estimated 4.9% (95% CI 4.7%, 5.1%) of adult women and 1.6% (1.3%, 1.9%) of adult men in London, for a female to male ratio of roughly 3 to one. In women, prevalence rises steadily with age from < 1% in women aged 18-30 to almost 8% in women 55-64. Thereafter, it declines. The peak prevalence in men also appears to be in middle age (2.5%; 1.1%, 5.7%). FM affects 3.3% (3.2%, 3.4%) of noninstitutionalized adults in London. Female sex, middle age, less education, lower household income, being divorced, and being disabled are associated with increased odds of having FM. CONCLUSION: FM is a common musculoskeletal disorder among Canadian adults, especially among women and persons of lower socioeconomic status.

Adolescent↗
PubMed1999

The London Fibromyalgia Epidemiology Study: comparing the demographic and clinical characteristics in 100 random community cases of fibromyalgia versus controls.

OBJECTIVE: To identify demographic and clinical features that distinguish fibromyalgia (FM) from other chronic widespread pain. METHODS: We identified 100 confirmed FM cases, 76 widespread pain controls, and 135 general controls in a random community survey of 3395 noninstitutionalized adults living in London, Ontario. FM cases were distinguished from pain controls using the 1990 American College of Rheumatology (ACR) classification criteria for FM. RESULTS: The mean age of FM cases was 47.8 years (range 19 to 86), the same as for pain controls; 86% of FM cases were female versus 67.1% of pain controls (p < 0.01). FM cases were less educated than general controls (p = 0.03). Male and female FM cases were similar, except females were older and reported more major symptoms (both p = 0.02). FM cases reported more severe pain and fatigue, more symptoms, more major symptoms, and worse overall health than pain controls or general controls. The most commonly reported major symptoms among FM cases were musculoskeletal pain (77.3%), fatigue (77.3%), severe fatigue lasting 24 h after minimal activity (77.0%), nonrestorative sleep (65.7%), and insomnia (56.0%). Subjects with 11-14 tender points were more similar to those with 15-18 tender points than to those with 7-10 points in 11 of 14 clinical variables. On multivariate analysis, 4 symptoms distinguished FM cases from pain controls: pain severity (p = 0.004), severe fatigue lasting 24 h after minimal activity (p = 0.006), weakness (p = 0.008), and self-reported swelling of neck glands (p = 0.01). CONCLUSION: In the general population, adults who meet the ACR definition of FM appear to have distinct features compared to those with chronic widespread pain who do not meet criteria.

Adult↗
PubMed1997

Effects of beta 2-agonist- and dexamethasone-treatment on relaxation and regulation of beta-adrenoceptors in human bronchi and lung tissue.

1. Long-term treatment with beta 2-adrenoceptor agonists can lead to a decreased therapeutic efficacy of bronchodilatation in patients with obstructive pulmonary disease. In order to examine whether or not this is due to beta-adrenoceptor desensitization, human bronchial muscle relaxation was studied in isolated bronchial rings after pretreatment with beta 2-adrenoceptor agonists. Additionally, the influence of pretreatment with dexamethasone on desensitization was studied. 2. The effect of beta 2-agonist incubation alone and after coincubation with dexamethasone on density and affinity of beta-adrenoceptors was investigated by radioligand binding experiments. 3. In human isolated bronchi, isoprenaline induces a time- and concentration-dependent beta-adrenoceptor desensitization as judged from maximal reduction in potency by a factor of 7 and reduction of 73 +/- 4% in efficacy of isoprenaline to relax human bronchial smooth muscle. 4. After an incubation period of 60 min with 100 mumol l-1 terbutaline, a significant decline in its relaxing efficacy (81 +/- 8%) and potency (by a factor 5.5) occurred. 5. Incubation with 30 mumol l-1 isoprenaline for 60 min did not impair the maximal effect of a subsequent aminophylline response but led to an increase in potency (factor 4.4). 6. Coincubation of dexamethasone with isoprenaline (120 min; 30 mumol l-1) preserved the effect of isoprenaline on relaxation (129 +/- 15%). 7. In radioligand binding experiments, pretreatment of lung tissue for 60 min with isoprenaline (30 mumol l-1) resulted in a decrease in beta-adrenoceptor binding sites (Bmax) to 64 +/- 1.6% (P < 0.05), while the antagonist affinity (KD) for [3H]-CGP-12177 remained unchanged. 8. In contrast, radioligand binding studies on lung tissue pretreated with either dexamethasone (30 mumol l-1) or isoprenaline (30 mumol l-1) plus dexamethasone (30 mumol l-1) for 120 min did not lead to a significant change of Bmax (160 +/- 22.1% vs 142.3 +/- 28.7%) or KD (5.0 nmol l-1 vs 3.5 nmol l-1) compared to the controls. 9. In conclusion, pretreatment of human bronchi with beta-adrenoceptor agonists leads to functional desensitization and, in lung tissue, to down-regulation of beta-adrenoceptors. This effect can be counteracted by additional administration of dexamethasone. Our model of desensitization has proved useful for the identification of mechanisms of beta-adrenoceptor desensitization and could be relevant for the evaluation of therapeutic strategies to counteract undesirable effects of long-term beta-adrenoceptor stimulation.

Adrenergic beta-2 Receptor Agonists↗
PubMed1997

Occupational exposure to desflurane and isoflurane during cardiopulmonary bypass: is the gas outlet of the membrane oxygenator an operating theatre pollution hazard?

We have compared occupational exposure to isoflurane and desflurane during cardiopulmonary bypass, with and without a scavenging system at the membrane oxygenator outlet. Trace concentrations of volatile anaesthetics were measured by a direct reading instrument in 40 elective heart surgery procedures. Measurements were obtained in the breathing zones of the anaesthetist and perfusionist. When a scavenging system was used, median desflurane values were less than 0.3 ppm and isoflurane values less than 0.2 ppm. Without a scavenging system values were, in general, three- (isoflurane) to five- (desflurane) fold higher. We conclude that the use of a scavenging system at the membrane oxygenator outlet can reduce occupational exposure to volatile anaesthetics. We therefore recommend routine use of scavenging devices during cardiopulmonary bypass.

Adult↗
PubMed1997

Occupational exposure to sevoflurane, halothane and nitrous oxide during paediatric anaesthesia. Waste gas exposure during paediatric anaesthesia.

We report the findings of a study on exposure of operating room staff to sevoflurane, halothane and nitrous oxide during induction and maintenance of anaesthesia in children. Concentrations of anaesthetic agents in the operating theatre were measured directly by highly sensitive, photoacoustic infrared spectrometer during 20 anaesthetics. Samples were taken from the breathing zones of the anaesthetist and the circulating nurse. The operating theatre was of modern design with an air conditioning system providing 20 changes of air each hour. The threshold values of 100 ppm N2O, 50 ppm isoflurane and 10 ppm halothane recommended by the United Kingdom Committee for Occupational Safety and Health (COSH) were exceeded in several cases for a short time during mask induction. After tracheal intubation, trace concentrations of sevoflurane, halothane and N2O were mostly under the recommended levels and comparable to levels measured during adult anaesthesia.

Adult↗
PubMed1997

Liver transplant in adult Still's disease.

Adult Still's disease (ASD) is an uncommon form of polyarthritis associated with numerous systemic manifestations, including hepatic involvement. Rarely, liver involvement can be fatal. We describe the case of a young man with ASD with terminal liver failure who required a life saving liver transplant.

Adult↗
PubMed1996

Functional restoration. Returning patients with chronic low back pain to work--revolution or fad?

STUDY DESIGN: A review was performed to assess the basis for functional restoration programs in returning patients with chronic low back pain to work. OBJECTIVE: To review and assess the effectiveness of functional restoration programs in the treatment of chronic low back pain. SUMMARY OF BACKGROUND DATA: Functional restoration programs generally use an aggressive program of physical exercises and psychosocial support with the focus on improving function despite the pain. METHODS: A review was conducted of significant papers presenting results of large clinical trials that used functional restoration programs. RESULTS: Several influential studies have reported statistically significant improvement in return-to-work rates of treated patients. The comparison groups consisted of treatment failures and/or patients refused entry to the programs because of insurers refusal to pay. Selection bias, incomplete follow-up, and inappropriate allocation of compared patients cast doubt on the effectiveness of these functional restoration programs. The only published prospective randomized clinical trial failed to demonstrate the efficacy of a functional restoration program. CONCLUSIONS: Further clinical trials based on sound methodology are needed.

Disability Evaluation↗
PubMed1996

The efficacy of dexamethasone iontophoresis for the treatment of rheumatoid arthritic knees: a pilot study.

OBJECTIVE: To examine the efficacy of dexamethasone sodium phosphate (DEX) iontophoresis for the treatment of rheumatoid arthritis (RA) of the knee, and to obtain statistical information for a future randomized controlled trial (RCT). METHODS: Ten subjects with RA, ranging in age from 34-75, were randomly assigned to either the experimental or placebo group. Iontophoresis treatments were given to both groups on days 1, 3, and 5. Five subjects in the experimental group received a mixture of 1 ml of DEX (4 mg/ml) and 1 ml of injectable sterile water; those in the placebo group received 2 ml of saline solution. Pain on movement, at rest, and on pressure, active joint count, and active range of motion, were evaluated on days 1, 5, and 20. The patient's global assessment of treatment efficacy was also assessed on days 5 and 20. Mann-Whitney U tests and Friedman two-way analyses of variance were performed for statistical analyses. RESULTS: Pain at rest was found to be statistically different between the two groups (P = 0.0317). Statistical significance was also found over time for pain on movement within the experimental group (P = 0.0224). CONCLUSION: The results suggest that DEX iontophoresis is more effective than placebo in relieving pain at rest and on movement in the RA knee. Based on the study data, a total of 40 subjects will be required for an RCT of a similar nature.

Activities of Daily Living↗
PubMed1996

Risk factors for adult Still's disease.

OBJECTIVE: To assess risk factors for adult Still's disease (ASD). METHODS: A matched case-control study of 60 patients with ASD and 60 same sex siblings closest in age was conducted. Subjects were recruited from cohorts in Eastern Canada, Pittsburgh, and the Arthritis, Rheumatism, and Aging, Medical Information Systems (ARAMIS). A questionnaire was used to obtain data on demographic characteristics, education, income, occupation, exposure to toxic substances, stress, and medical history. RESULTS: 116 patients with ASD were identified, of which 104 participated. 86 identified same sex siblings, of which 60 replied. When compared to same sex siblings, ASD patients were similar with respect to education and occupation but had a trend to higher median income. There were no significant associations of ASD with smoking, alcohol consumption, individual toxic substances, vaccination, blood transfusion, minor or major surgery, pregnancy, or diet in the year preceding disease onset. There were no significant associations with tonsillectomy or adenoidectomy, appendectomy, asthma, hay fever, allergy shots, or pregnancy at any time preceding the onset of disease. There was a statistically nonsignificant increase in a history of exposure to coal dust [odds ratio (OR) 3.0; 95% confidence interval (CI) 0.30 to 28.84], in allergy preceding the onset of disease (OR 2.67; 95% CI 0.71 to 10.05), and in oral contraceptive use in the year preceding onset (OR 2.00; 95% CI 0.18 to 22.06). Stressful life events (OR 2.56; 95% CI 1.18 to 5.52) in the year preceding onset was significantly associated with increased risk for ASD. This positive association should be treated with caution unless confirmed by a separate study. CONCLUSION: This exploratory study of risk factors for ASD draws attention to stress as a potentially important risk factor, while likely excluding a considerable number of others.

Adult↗
PubMed1995

A controlled study of the long-term prognosis of adult Still's disease.

PURPOSE: To assess the long-term prognosis of patients with adult Still's disease for physical and psychological disability, pain, social functioning, social support, medication use, formal education, occupation, time lost from work, and family income, and to contrast these results with those of same-sex sibling controls. PATIENTS AND METHODS: Patients were recruited from medical center-based cohorts in Pittsburgh and Eastern Canada and from a national survey of rheumatologists. Patients and same-sex sibling controls completed the Health Assessment Questionnaire for physical disability, the psychological and social function domains of the Arthritis Impact Measurement Scales, and the Interpersonal Skills Evaluation List questionnaire for social support, and replied to questions on medication use, formal education, occupation, time lost from work, and family income. RESULTS: One hundred four of 111 eligible adult Still's patients (94%) provided data. They identified 86 same-sex sibling controls, of whom 60 (70%) participated. The mean duration of adult Still's disease was 10 years. Approximately half of patients continued to require medication even 10 years after diagnosis. Patients had significantly higher levels of pain, physical disability, and psychological disability when compared with the controls. However, the levels of pain and physical disability were low compared to patients with other rheumatic diseases. Educational achievement, occupational prestige, social functioning and support, time lost from work, and family income were similar for both patients and controls. CONCLUSIONS: Despite causing disability, pain, and, in many, the need for long-term medication, patients with adult Still's disease are resilient. The disease did not interfere with educational attainment, occupational prestige, social functioning and support, time lost from work, or family income.

Adolescent↗
PubMed1995

Work disability evaluation and the fibromyalgia syndrome.

Fibromyalgia syndrome (FMS) is a common and costly cause of work disability. Patients with FMS, nevertheless, encounter considerable difficulties in their assessment of claims for disability payments. Factors that contribute to FMS as an important cause of disability are its high prevalence, the patients' perception of severe discomfort, and poor function. Disability evaluation in FMS is controversial for several reasons including lack of acceptance of the diagnosis, concurrent psychological abnormalities, difficulties in objectifying disability, deficiencies in instruments of evaluation, the uncertain efficacy of treatment, and physician attitudes. Third parties appear to have inappropriate expectations of the physician's role in determining disability. We suggest that the process of disability evaluation be improved by more objective assessments and by the inclusion of other health professionals in assessing disability and necessary retraining. Further research is needed to develop better instruments for measuring disability, to assess the long-term effects of various treatments, and to clarify the contributions of the work place and of compensation in causing or aggravating FMS.

Adult↗
PubMed1995

Fibromyalgia in rheumatology practice: a survey of Canadian rheumatologists.

OBJECTIVE: To determine the perceived proportion of fibromyalgia (FMS) among new consultations in rheumatology practices relative to other rheumatologic disorders. METHODS: We conducted a cross sectional random mail survey of 100 Canadian rheumatologists. The sampling frame was the 1991 membership directory of the Canadian Rheumatology Association from which 100 nonpediatric rheumatologists practising in Canada were selected by stratified random sampling. RESULTS: Results from 89 respondents indicate that FMS is perceived to be one of the 3 most common diagnoses among new patient consultations across Canada. Perceived incidence was not affected by urban size or university affiliation of practice. FMS was the only rheumatologic disorder believed by a majority of respondents to have increased in proportion over the past 5 years. CONCLUSION: In Canada, FMS appears to contribute to a high proportion of outpatient care in rheumatology.

Canada↗
PubMed1994

Septic arthritis due to Mycobacterium marinum.

We describe a patient with septic arthritis and osteomyelitis of the ring finger due to Mycobacterium marinum. A review of the literature shows fewer than 40 reported cases of joint infection with this organism. Most of the patients reported had been previously in good health, and had been in contact with fish or otherwise involved in aquatic activities. The arthritis affects mainly the hands or wrists and is insidious in onset. Delay in diagnosis, and initial inappropriate treatment with intraarticular steroids are frequent. Therapy with antibiotics and/or surgical debridement is usually successful.

Arthritis, Infectious↗