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A J Silman

Publications and source records attributed to A J Silman.

At least 19 recordsLinked to original sources
PubMed2000

Characterizing the quantitative genetic contribution to rheumatoid arthritis using data from twins.

OBJECTIVE: Twin concordance data for rheumatoid arthritis (RA) on their own provide only limited insight into the relative genetic and environmental contribution to the disease. We applied quantitative genetic methods to assess the heritability of RA and to examine for evidence of differences in the genetic contribution according to sex, age, and clinical disease characteristics. METHODS: Data were analyzed from 2 previously published nationwide studies of twins with RA conducted in Finland and the United Kingdom. Heritability was assessed by variance components analysis. Differences in the genetic contribution by sex, age, age at disease onset, and clinical characteristics were examined by stratification. The power of the twin study design to detect these differences was examined through simulation. RESULTS: The heritability of RA was 65% (95% confidence interval [95% CI] 50-77) in the Finnish data and 53% (95% CI 40-65) in the UK data. There was no significant difference in the strength of the genetic contribution according to sex, age, age at onset, or disease severity subgroup. Both study designs had power to detect a contribution of at least 40% from the common family environment, and a difference in the genetic contribution of at least 50% between subgroups. CONCLUSION: Genetic factors have a substantial contribution to RA in the population, accounting for approximately 60% of the variation in liability to disease. Although tempered by power considerations, there is no evidence in these twin data that the overall genetic contribution to RA differs by sex, age, age at disease onset, and disease severity.

Adult↗
PubMed2000

The association between chronic widespread pain and mental disorder: a population-based study.

OBJECTIVE: Patients with chronic widespread pain (CWP) have been reported to have a greater prevalence of mental disorders and somatization than that found in the general population, but the true association between CWP and mental disorders is unknown. In this study, we investigated whether there is an increased prevalence of mental disorder in people with CWP from the general population. We also describe the psychiatric diagnoses associated with CWP. METHODS: In a population-based case-control study, 1,953 subjects (75% of a random sample of individuals age 18-65 years) completed a questionnaire that included a pain assessment and the 12-item General Health Questionnaire (GHQ-12). Of 710 subjects scoring >1 on the GHQ-12, 301 were assessed further using a structured psychiatric interview and detailed assessment of medical records to identify cases of mental disorder, in accordance with criteria of the 10th edition of the International Classification of Diseases. The association between CWP and mental disorder was modeled using logistic regression, adjusting for possible confounders including age, sex, and nonresponders. RESULTS: We estimated the overall population prevalence of mental illness to be 11.9%. The odds of having a mental disorder for subjects with versus those without CWP were 3.18 (95% confidence interval 1.97-5.11). Most subjects with mental disorders were diagnosed as having mood and anxiety disorders. Only 3 cases of somatoform disorders were identified, and all were associated with pain. CONCLUSION: This study, although unable to demonstrate a cause-and-effect relationship, showed that 16.9% of those with CWP were estimated to have a psychiatric diagnosis, suggesting that these disorders should be identified and treated.

Adolescent↗
PubMed2000

Validity of self-report of fractures: results from a prospective study in men and women across Europe. EPOS Study Group. European Prospective Osteoporosis Study Group.

In population-based studies of osteoporosis, ascertainment of fractures is typically based on self-report, with subsequent verification by medical records. The aim of this analysis was to assess the validity of self-report of incident nonspine fractures using a postal questionnaire. The degree of overreporting of fracture (false positives) was assessed by comparing self-reports of new fracture from respondents in the multicenter European Prospective Osteoporosis Study with data from other sources including radiographs and medical records. In the analysis, 563 subjects reported nonspine fractures. Verification of the presence of fracture was possible in 510 subjects. Of these, fractures were not confirmed in 11% (false positives). The percentage of false positives was greater in men than in women (15% vs 9%, p = 0.04), and less for fractures of the distal forearm and hip than for fractures at other sites. In a separate study, the degree of underreporting (false negatives) was assessed by follow-up of 251 individuals with confirmed fracture ascertained from the records of fracture clinics in three European centers (Lubeck, Oviedo, Warsaw). Questionnaire responses were received from 174 (69%) subjects. Of these, 12 (7%) did not recall sustaining a fracture (false negatives). The percentage of false negatives was lower for hip and distal forearm fractures with only 3 of 90 (3%) such fractures not recalled. Using the combined data from both studies, of those who reported a 'date' of fracture on the questionnaire, 91% of subjects were correct to within 1 month of the actual date of the fracture. A postal questionnaire is a relatively simple and accurate method for obtaining information about the occurrence of hip and distal forearm fractures, including their timing. Accuracy of ascertainment of fractures at other sites is less good and where possible self-reported fractures at such sites should be verified from other sources.

Aged↗
PubMed2000

Development and validation of a questionnaire to assess disabling foot pain.

This study outlines the design and validation of a new self-administered instrument for assessing foot pain and disability. The 19-item questionnaire was tested on 45 rheumatology patients, 33 patients who had attended their general practitioner with a foot-related problem and 1000 responders to a population survey of foot disorders. Levels of reported disability were found to be greatest for rheumatology patients and least for community subjects. In addition, the instrument was able to detect differences in disability levels reported by community subjects who did and did not consult with a health care professional and those who did and did not have a history of past and current foot pain. A good level of agreement was found when items on the questionnaire were compared with similar items on the ambulation sub-scale of the Functional Limitation Profile questionnaire. A Cronbach's alpha value of 0.99 and item-total correlation values between 0.25 and 0.62 confirmed the internal consistency of the instrument. Finally the results of a principal components analysis identified three constructs that reflected disabilities that are associated with foot pain: functional limitation, pain intensity and personal appearance. The design of the foot disability questionnaire makes it a suitable instrument for assessing the impact of painful foot conditions in both community and clinical populations.

Adult↗
PubMed2000

Hip geometry, bone mineral distribution, and bone strength in European men and women: the EPOS study.

Hip geometry and bone mineral density (BMD) have been shown previously to relate, independently of each other, to risk of hip fracture. We used Lunar DPX "beta" versions of hip strength analysis (HSA) and hip axis length (HAL) software to analyze scans from ten representative age-stratified population samples in the European Prospective Osteoporosis Study (EPOS). All 1617 subjects were >50 years of age, and 1033 were women. The data were modeled with gender and center as categorical variables. The bone mineral density of the upper half of the femoral neck declined at a faster rate with age than that in the lower half. Femoral neck cross-sectional moment of inertia (CSMI), a measure of resistance to bending, showed no significant age reduction in either gender. However, height and weight effects on CSMI were significantly more beneficial in men than in women (0.002 < p < 0.012) and the weight effect appeared to be mediated by bone mineral content (BMC). Compressive stress (Cstress), defined as the stress in the femoral neck at its weakest cross section arising from a standardized fall, was higher in women. Although Cstress increased with body weight when BMC was held constant, in practice it fell through the association and statistical interaction of rising body weight with rising BMC. HAL, as expected, was strongly positively associated with male gender and also height (p < 0.0001). Hip strength-related indices were markedly center-dependent. Significant differences (p < 0.0001) were noted between the centers for all the variables investigated that related to hip geometry. Adjustment for femoral neck bone mineral content (totBMC) showed these center differences to account for >50% of center variation in hip strength, which remained highly significant (p < 0.0001). We conclude that there are substantial geographical differences in femoral neck geometry as well as in BMD. These geometric variations may contribute to the large variations in hip fracture risk across Europe. The effects of aging on hip strength need to be explored in longitudinal studies.

Age Factors↗
PubMed2000

Does location of vertebral deformity within the spine influence back pain and disability? European Vertebral Osteoporosis Study (EVOS) Group.

OBJECTIVE: Vertebral deformity is associated with back pain and disability. The aim of this analysis was to determine whether location within the spine influences the strength of association between vertebral deformity, back pain and disability. METHODS: Men and women aged 50 years and over were recruited from population registers in 30 European centres. Subjects were invited for an interviewer administered questionnaire, and for lateral spinal radiographs. The questionnaire included questions about back pain, general health and functional ability. The spinal radiographs were evaluated morphometrically and vertebral deformity defined according to the McCloskey-Kanis method. RESULTS: 756 (11.7%) men and 885 (11. 8%) women had evidence of one or more vertebral deformities. Among women with a single deformity, after adjusting for age and centre, those with a lumbar deformity were more likely than those with a thoracic deformity to report back pain, both currently (OR=1.4; 95% CI 1.0, 2.0) and in the past year (OR=1.5; 95% CI 1.0, 2.3). No association was observed in men. Among women with two deformities, those with adjacent deformities were more likely than those with non-adjacent deformities to report poor general health (OR=2.2; 95%CI 0.9, 5.6), impaired functional ability (OR=1.9; 95%CI 0.8, 4. 7) and current back pain (OR=2.1; 95%CI 0.9, 4.9), though none of these associations were statistically significant. By contrast, among men, non-adjacent deformities were associated with impaired functional ability compared with those with adjacent deformities. CONCLUSION: Location within the spine influences the strength of association between self reported health factors and vertebral deformity.

Aged↗
PubMed2000

Occupational risk factors for shoulder pain: a systematic review.

OBJECTIVES: To systematically evaluate the available evidence on occupational risk factors of shoulder pain. METHODS: Relevant reports were identified by a systematic search of Medline, Embase, Psychlit, Cinahl, and Current Contents. The quality of the methods of all selected publications was assessed by two independent reviewers using a standardised checklist. Details were extracted on the study population, exposures (physical load and psychosocial work environment), and results for the association between exposure variables and shoulder pain. RESULTS: 29 Studies were included in the review; three case-control studies and 26 cross sectional designs. The median method score was 60% of the maximum attainable score. Potential risk factors related to physical load and included heavy work load, awkward postures, repetitive movements, vibration, and duration of employment. Consistent findings were found for repetitive movements, vibration, and duration of employment (odds ratio (OR) 1.4-46 in studies with method scores >/= 60%). Nearly all studies that assessed psychosocial risk factors reported at least one positive association with shoulder pain, but the results were not consistent across studies for either high psychological demands, poor control at work, poor social support, or job dissatisfaction. Studies with a method score >/=60% reported ORs between 1.3 and 4.0. Substantial heterogeneity across studies for methods used for exposure assessment and data analysis impeded statistical pooling of results. CONCLUSIONS: It seems likely that shoulder pain is the result of many factors, including physical load and the psychosocial work environment. The available evidence was not consistent across studies, however, and the associations were generally not strong. Future longitudinal research should evaluate the relative importance of each individual risk factor and the role of potential confounding variables-such as exposure during leisure time-to set priorities for the prevention of shoulder pain in occupational settings.

Bias↗
PubMed2000

Hospital referrals for low back pain: more coherence needed.

Low back pain is a common reason for hospital referral but little is known of the resulting workload in different specialties. All new outpatient attendances for conditions with low back pain were recorded over one month in a teaching hospital and a district general hospital. The patients were seen in at least ten specialties and two-fifths of them had been seen previously with the same symptom in another department. In the two hospitals, low back pain accounted for 15% and 12% of all new outpatient attendances. A more coherent referral policy is needed.

Hospital Records↗
PubMed2000

Risk factors for vertebral deformities in men: relationship to number of vertebral deformities. European Vertebral Osteoporosis Study Group.

Recent epidemiological studies suggest a similar overall prevalence of vertebral deformity in men to that in women, though the influence of increasing age on the prevalence of vertebral deformity is less marked in men. However, most affected men have only a single or two vertebral deformities, which may be unrelated to osteoporosis. The aim of this study was to examine the role of risk factors, previously demonstrated to be associated with vertebral osteoporosis in females, in men with single/dual deformities compared to those with multiple deformities. Age stratified random samples of men aged 50 years and over were recruited from population registers in 30 European centers as part of the European Vertebral Osteoporosis Study (EVOS). Subjects had a lateral spinal radiograph and the presence of vertebral deformity was determined using the McCloskey algorithm. Lifestyle and other risk factor data were obtained from an interviewer-administered questionnaire. In all 6937 men with a mean age of 64.4 (SD = 8.5) years were studied of whom 738 (10.6%) subjects had one or two deformities, and 109 (1.6%) subjects had three or more deformities. There was a marked increase in the prevalence of multiple vertebral deformities with increasing age, but only a modest effect of age on the prevalence of single deformities. Associations between various risk factors for osteoporosis and vertebral deformity were analyzed separately in men with single/dual vertebral deformity from those with three or more deformities using logistic regression. After adjustment for age, there were statistically significant associations between the following risk factors and multiple deformities: previous hip fracture (odds ratio [OR] 10.5), lack of regular physical activity (OR 2.9), low body mass (OR 2.5), and previous steroid use (OR 2.3). By contrast, there were only weak associations with these same variables in males with single/dual deformities and, apart from poor self-reported general health, all of the 95% confidence intervals spanned unity. There was no difference in the reporting of very heavy levels of physical activity under the age of 50 years between men with single/dual deformities and those with multiple deformities. In conclusion, men with multiple deformities showed a similar pattern of risk factor association to those seen in women with vertebral deformity, in contrast to men with single/dual deformities.

Aged↗
PubMed1999

Does the presence of postmenopausal symptoms influence susceptibility to vertebral deformity? European Vertebral Osteoporosis Study (EVOS) Group.

BACKGROUND: Previous reports suggest a possible increased risk of osteoporosis in those with postmenopausal symptoms. There are, however, no data from population samples, exploring the relationship between postmenopausal symptoms and vertebral osteoporosis. AIM: To determine if there is an association between self-reported postmenopausal symptoms and radiographic vertebral deformity. METHODS: Women aged 50 years and over were recruited from population registers in 30 European centres and invited to attend for an interviewer administered questionnaire and lateral thoracic and lumbar spine radiographs. The questionnaire sought information about aspects of lifestyle, personal, medical and gynaecological history, including postmenopausal symptoms: flushing, sleep disturbance and 'other' symptoms. Radiographs were taken according to a standard protocol and evaluated morphometrically. Vertebral deformity was defined according to the McCloskey-Kanis method. Bone mineral density data were obtained in a subsample of women at both the spine and femoral neck. RESULTS: A total of 4023 postmenopausal women, aged 50-64 years, were studied: 73% reported a history of flushing, 45% sleep disturbance and 23% 'other' symptoms, at or around their menopause. The prevalence of vertebral deformity was 8.2%. Those with postmenopausal symptoms were slightly younger and more likely to have ever taken hormone replacement therapy (HRT) than those without symptoms. After adjusting for potential confounders (age, centre, body mass index, cigarette smoking and HRT) there was no association between deformity and any of the postmenopausal symptoms: flushing (odds ratio (OR) 1.0; 95% confidence intervals (CI) 0.8, 1.3), sleep disturbance (OR 1.0; 95% CI 0.8, 1.2), 'other' symptoms (OR 0.9; 95% CI 0.7, 1.3). Amongst women who had ever taken HRT, however, those with vertebral deformity were more likely to report a history of flushing (OR 2.1; 95% CI 0.9,4.8). CONCLUSION: A history of postmenopausal symptoms per se does not appear to be associated with increased susceptibility to vertebral osteoporosis. However, women with more severe symptoms (as suggested by their use of HRT) may be at increased risk.

Bone Density↗
PubMed1999

Short-term physical risk factors for new episodes of low back pain. Prospective evidence from the South Manchester Back Pain Study.

STUDY DESIGN: A prospective population-based cohort study performed in South Manchester, United Kingdom. OBJECTIVES: To determine whether nonoccupational physical activity and indicators of physical stress on the spine predict low back pain in the short term. SUMMARY OF BACKGROUND DATA: There is evidence that physical activity outside the workplace helps to protect against low back pain in the long term. However, such activity may injure or stress the spine in the short term. METHODS: A baseline survey questionnaire identified 2715 adults, aged 18-75 years, with no low back pain at the time of the survey. Information on potential predictors of low back pain also was obtained. New episodes of back pain were identified during the subsequent year. RESULTS: A new low back pain episode occurred in 34% of men and 37% of women. Poor general health at baseline was the strongest predictor of a new episode of pain (men: relative risk (RR) 1.5, 95% confidence intervals (CI) 0.8, 2.7; women: RR 2.2, 95% CI 1.2, 4.0). High weight was associated with subsequent low back pain in women (RR 1.4; 95% CI 1.0, 2.0), but neither height nor weight predicted low back pain in men. A self-rated low level of physical activity was not consistently linked with subsequent low back pain, nor were specific nonoccupational physical activities, apart from home-improvement work in men and regular sports in women. CONCLUSION: Although some specific activities may be hazardous to the back, physical activity outside the workplace does not increase the short-term risk of low back pain overall. Leisure-time physical activity is not a hazard to the back, whereas poor physical health in both genders and heavier weight in women do increase the risk of new low back pain episodes in the short term.

Adult↗
PubMed1999

Predicting who develops chronic low back pain in primary care: a prospective study.

OBJECTIVES: To quantify the relative contribution of premorbid and episode specific factors in determining the long term persistence of disabling symptoms of low back pain. DESIGN: Prospective cohort study. SETTING: Two general practices in the south Manchester area. PARTICIPANTS: 180 patients, who previously participated in a cross sectional population survey, who consulted because of low back pain during the study period. They were followed at 1 week and 3 and 12 months after consultation. MAIN OUTCOME MEASURE: Persistent disabling low back pain in the 12 months after the consultation. RESULTS: Disabling low back pain persisted in one third of participants after consultation and was more common with increasing age, among those with a history of low back pain, and in women. Persistence of symptoms was associated with "premorbid" factors (high levels of psychological distress (odds ratio 3.3; 95% confidence interval 1.5 to 7.2), poor self rated health (3.6; 1.9 to 6.8), low levels of physical activity (2.8; 1.4 to 5.6), smoking (2. 1; 1.0 to 4.3), dissatisfaction with employment (2.4; 1.3 to 4.5)) and factors related to the episode of low back pain (duration of symptoms, pain radiating to the leg (2.6; 1.3 to 5.1), widespread pain (6.4; 2.7 to 15), and restriction in spinal mobility). A multivariate model based on six factors identified groups whose likelihood of persistent symptoms ranged from 6% to 70%. CONCLUSIONS: The presence of persistent low back pain is determined not only by clinical factors associated with pain but also by the premorbid state.

Adolescent↗
PubMed1999

Interferon-alpha does not improve outcome at one year in patients with diffuse cutaneous scleroderma: results of a randomized, double-blind, placebo-controlled trial.

OBJECTIVE: To determine whether interferon-alpha (IFNalpha) reduces the severity of skin involvement in early (<3 years) diffuse scleroderma. METHODS: In a randomized, placebo-controlled, double-blind trial, 35 patients with early scleroderma received subcutaneous injections of either IFNalpha (13.5 x 10(6) units per week in divided doses) or indistinguishable placebo. Outcomes assessed were the modified Rodnan skin score, as determined by a single observer at baseline, 6 months, and 12 months, as well as data on renal, cardiac, and lung function. Pre- and posttreatment skin biopsy samples were analyzed and blood was obtained for assessment of procollagen peptide levels. RESULTS: There were 11 withdrawals from the IFNalpha group and 3 from the placebo group due to either toxicity, lack of efficacy, or death. In the intent-to-treat analysis, there was a greater improvement in the skin score in the placebo group between 0 and 12 months (mean change IFNalpha -4.7 versus placebo -7.5; P = 0.36). There was also a greater deterioration in lung function in patients receiving active therapy, as assessed by either the forced vital capacity (mean change IFNalpha -8.2 versus placebo +1.3; P = 0.01) or the diffusing capacity for carbon monoxide (mean change IFNalpha -9.3 versus placebo +4.7; P = 0.002). Skin biopsy showed no significant decrease in collagen synthesis in the IFNalpha group, and no significant differences in the levels of procollagen peptides were seen between the 2 groups. CONCLUSION: This study suggests that IFNalpha is of no value in the treatment of scleroderma, and that it may in fact be deleterious.

Adolescent↗
PubMed1999

Does rheumatoid arthritis remit during pregnancy and relapse postpartum? Results from a nationwide study in the United Kingdom performed prospectively from late pregnancy.

OBJECTIVE: To ascertain the influence of pregnancy on disease activity in women with rheumatoid arthritis (RA) during pregnancy and postpartum. METHODS: One hundred forty pregnant women were recruited from a nationwide campaign and were followed prospectively in the last trimester and at 1 and 6 months postpartum. Standardized assessment of joint symptoms, examination of inflamed joints, and the Health Assessment Questionnaire (HAQ) were the main measures of disease activity. RESULTS: There was only a modest fall in HAQ scores during pregnancy, with >25% of women having substantial levels of disability. Other parameters of disease activity showed a greater trend toward improvement, although only 23 (16%) were in complete remission (no joints with active disease and no therapy). Similarly, there was relatively little change in the distribution of HAQ scores from pregnancy to postpartum. There was, however, a statistically significant increase in the mean number of inflamed joints compared with the findings during pregnancy. Analysis of the possible influence of treatment suggested that therapy was associated with more severe disease and was not related to reduction in disease activity. CONCLUSION: This, the largest prospective study of the influence of pregnancy on RA activity, has demonstrated widespread variability in disease response.

Adult↗
PubMed1999

Estimating the incidence of rheumatoid arthritis: trying to hit a moving target?

OBJECTIVE: To examine the effect of delay between symptom onset and notification to an arthritis register and the effect of application of the American College of Rheumatology (ACR; formerly, the American Rheumatism Association) 1987 criteria in a cumulative manner on estimates of the incidence of rheumatoid arthritis (RA). METHODS: General practitioners and/or hospital consultants in the Norwich Health Authority, Norfolk, UK, notified the Norfolk Arthritis Register (NOAR) of all patients who had onset of inflammatory polyarthritis (swelling of > or =2 joints) during 1990. The patients were assessed within 2 weeks of notification and annually thereafter. The ACR 1987 criteria for RA were applied at each assessment. Age- and sex-specific incidence rates were calculated. RESULTS: If up to 12 months elapsed from symptom onset to notification to NOAR and the ACR criteria were applied at the baseline assessment, RA incidence estimates, age-adjusted to the population of England and Wales, were 30.8/100,000 for women and 12.7/100,000 for men. If up to 5 years elapsed from symptom onset to notification, these estimates rose by 45% for women and 36% for men. If up to 5 years elapsed between symptom onset and notification and the criteria were applied cumulatively, the estimates rose by 75% and 93% for women and men, respectively, compared with the 1-year data, reaching 54.0/100,000 for women and 24.5 per 100,000 for men. CONCLUSION: Accurate estimation of the incidence of RA requires long-term followup of patients who present with undifferentiated inflammatory polyarthritis. The highest age-adjusted estimates from this study are probably the best that are available.

Adolescent↗