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D Coggon

Publications and source records attributed to D Coggon.

At least 55 records · Page 3Linked to original sources
PubMed2000

Risk factors for the incidence and progression of radiographic knee osteoarthritis.

OBJECTIVE: Preventive strategies against knee osteoarthritis (OA) require a knowledge of risk factors that influence the initiation of the disorder and its subsequent progression. This population-based longitudinal study was performed to address this issue. METHODS: Ninety-nine men and 255 women aged > or =55 years had baseline interviews and weight-bearing knee radiographs in 1990-1991. Repeat radiographs were obtained in 1995-1996 (mean followup duration 5.1 years, median age at followup 75.8 years). Risk factors assessed at baseline were tested for their association with incident and progressive radiographic knee OA by logistic regression. RESULTS: Rates of incidence and progression were 2.5% and 3.6% per year, respectively. After adjusting for age and sex, the risk of incident radiographic knee OA was significantly increased among subjects with higher baseline body mass index (odds ratio [OR] 18.3, 95% confidence interval [95% CI] 5.1-65.1, highest versus lowest third), previous knee injury (OR 4.8, 95% CI 1.0-24.1), and a history of regular sports participation (OR 3.2, 95% CI 1.1-9.1). Knee pain at baseline (OR 2.4, 95% CI 0.7-8.0) and Heberden's nodes (OR 2.0, 95% CI 0.7-5.7) were weakly associated with progression. Analyses based on individual radiographic features (osteophyte formation and joint space narrowing) supported differences in risk factors for either feature. CONCLUSION: Most currently recognized risk factors for prevalent knee OA (obesity, knee injury, and physical activity) influence incidence more than radiographic progression. Furthermore, these factors might selectively influence osteophyte formation more than joint space narrowing. These findings are consistent with knee OA being initiated by joint injury, but with progression being a consequence of impaired intrinsic repair capacity.

Aged↗
PubMed2000

Occupational physical activities and osteoarthritis of the knee.

OBJECTIVE: To assess the risk of knee osteoarthritis (OA) associated with kneeling, squatting, and other occupational activities. METHODS: We compared 518 patients who were listed for surgical treatment of knee OA and an equal number of control subjects from the same communities who were matched for sex and age. Histories of knee injury and occupational activities were ascertained at interview, height and weight were measured, and the hands were examined for Heberden's nodes. Data were analyzed by conditional logistic regression. RESULTS: After adjustment for body mass index (BMI), history of knee injury, and the presence of Heberden's nodes, risk was elevated in subjects who reported prolonged kneeling or squatting (odds ratio [OR] 1.9; 95% confidence interval [95% CI] 1.3-2.8), walking >2 miles/day (OR 1.9; 95% CI 1.4-2.8), and regularly lifting weights of at least 25 kg (OR 1.7; 95% CI 1.2-2.6) in the course of their work. The risks associated with kneeling and squatting were higher in subjects who also reported occupational lifting, and appeared to interact multiplicatively with the risk conferred by obesity. People with a BMI of > or =30 kg/m2 whose work had entailed prolonged kneeling or squatting had an OR of 14.7 (95% CI 7.2-30.2), compared with subjects with a BMI <25 kg/m2 who were not exposed to occupational kneeling or squatting. CONCLUSION: There is now strong evidence for an occupational hazard of knee OA resulting from prolonged kneeling and squatting. One approach to reducing this risk may lie in the avoidance of obesity in people who perform this sort of work.

Aged↗
PubMed2000

Sensory neural processing in work-related upper limb disorders.

Pain in the upper limb is a common complaint in adults, and is often attributed to or exacerbated by occupational activities. In many patients there is no demonstrable pathology in the neck or arm to account for the symptom, and this has prompted the hypothesis that such cases might arise through abnormal neural processing of sensory information with a lowering of pain thresholds. In this paper we review the evidence in support of this theory and suggest directions for future research.

Adult↗
PubMed2000

The Southampton examination schedule for the diagnosis of musculoskeletal disorders of the upper limb.

OBJECTIVES: Following a consensus statement from a multidisciplinary UK workshop, a structured examination schedule was developed for the diagnosis and classification of musculoskeletal disorders of the upper limb. The aim of this study was to test the repeatability and the validity of the newly developed schedule in a hospital setting. METHOD: 43 consecutive referrals to a soft tissue rheumatism clinic (group 1) and 45 subjects with one of a list of specific upper limb disorders (including shoulder capsulitis, rotator cuff tendinitis, lateral epicondylitis and tenosynovitis) (group 2), were recruited from hospital rheumatology and orthopaedic outpatient clinics. All 88 subjects were examined by a research nurse (blinded to diagnosis), and everyone from group 1 was independently examined by a rheumatologist. Between observer agreement was assessed among subjects from group 1 by calculating Cohen's kappa for dichotomous physical signs, and mean differences with limits of agreement for measured ranges of joint movement. To assess the validity of the examination, a pre-defined algorithm was applied to the nurse's examination findings in patients from both groups, and the sensitivity and specificity of the derived diagnoses were determined in comparison with the clinic's independent diagnosis as the reference standard. RESULTS: The between observer repeatability of physical signs varied from good to excellent, with kappa coefficients of 0.66 to 1.00 for most categorical observations, and mean absolute differences of 1.4 degrees -11.9 degrees for measurements of shoulder movement. The sensitivity of the schedule in comparison with the reference standard varied between diagnoses from 58%-100%, while the specificities ranged from 84%-100%. The nurse and the clinic physician generally agreed in their diagnoses, but in the presence of shoulder capsulitis the nurse usually also diagnosed shoulder tendinitis, whereas the clinic physician did not. CONCLUSION: The new examination protocol is repeatable and gives acceptable diagnostic accuracy in a hospital setting. Examination can feasibly be delegated to a trained nurse, and the protocol has the benefit of face and construct validity as well as consensus backing. Its performance in the community, where disease is less clear cut, merits separate evaluation, and further refinement is needed to discriminate between discrete pathologies at the shoulder.

Adult↗
PubMed2000

Prevalence and pattern of occupational exposure to hand transmitted vibration in Great Britain: findings from a national survey.

OBJECTIVES: To estimate the number of workers in Great Britain with significant occupational exposure to hand transmitted vibration (HTV). Also, to identify the occupations and industries where such exposures arise, and the main sources of exposure. METHODS: A questionnaire was posted to 22,194 men and women aged 16-64, comprising 21,201 subjects selected at random from the age-sex registers of 34 general practices in England, Scotland, and Wales, and a further 993 subjects selected at random from the central pay registers of the three armed services. Among other things, the questionnaire asked about exposure to sources of HTV in current and earlier employment. Responses were assessed by occupation and industry, and prevalence estimates for the country as a whole were derived from census information on occupational and industrial populations nationally. Estimates were also made in exposed workers of the average daily dose of vibration (A(8) root mean squared (rms) for the past week, based on their reported sources and durations of exposure. RESULTS: Usable questionnaires were returned by 12,907 subjects (overall response rate 58%). From these it was estimated that some 4.2 million men and 667 000 women in Great Britain are exposed to HTV at work in a 1 week period, and that personal daily exposures to vibration exceed a suggested action level equivalent to 2.8 ms(-2) for 8 hours (A(8) >2.8 ms(-2) rms) in at least 1.2 million men and 44,000 women. High estimated doses (A(8) >5 ms(-2) rms) arose most often in bricklayers and masons, gardeners and groundsmen, carpenters and joiners, electricians and electrical maintenance fitters, and builders and building contractors. The industries where high A(8) values most often arose were construction, motor vehicle repair and maintenance, manufacture of basic metals, and agriculture. The most common sources of exposure were hammer drills, hand held portable grinders, and jigsaws. CONCLUSIONS: Exposure to HTV is surprisingly prevalent, and preventive measures and health surveillance may be warranted for many men in Britain. Control strategies should focus on prevention at source, with priority accorded to the common sources of exposure and the occupations in which significant exposures tend to arise. Many vibratory tools that are common in Britain have been overlooked in previous surveys, highlighting an important focus for future research.

Adolescent↗
PubMed2000

Prevalence and pattern of occupational exposure to whole body vibration in Great Britain: findings from a national survey.

OBJECTIVES: To estimate the number of workers in Great Britain with significant occupational exposure to whole body vibration (WBV) and to identify the common sources of exposure and the occupations and industries where such exposures arise. METHODS: A postal questionnaire was posted to a random community sample of 22,194 men and women of working age. Among other things, the questionnaire asked about exposure to WBV in the past week, including occupational and common non-occupational sources. Responses were assessed by occupation and industry, and national prevalence estimates were derived from census information. Estimates were also made of the average estimated daily personal dose of vibration (eVDV). RESULTS: From the 12,907 responses it was estimated that 7.2 million men and 1.8 million women in Great Britain are exposed to WBV at work in a 1 week period if the occupational use of cars, vans, buses, trains, and motor cycles is included within the definition of exposure. The eVDV of >374,000 men and 9000 women was estimated to exceed a proposed British Standard action level of 15 ms(-1.75). Occupations in which the estimated exposures most often exceeded 15 ms(-1.75) included forklift truck and mechanical truck drivers, farm owners and managers, farm workers, and drivers of road goods vehicles. These occupations also contributed the largest estimated numbers of workers in Great Britain with such levels of exposure. The highest estimated median occupational eVDVs were found in forklift truck drivers, drivers of road goods vehicles, bus and coach drivers, and technical and wholesale sales representatives, among whom a greater contribution to total dose was received from occupational exposures than from non-occupational ones; but in many other occupations the reverse applied. The most common sources of occupational exposure to WBV are cars, vans, forklift trucks, lorries, tractors, buses, and loaders. CONCLUSIONS: Exposure to whole body vibration is common, but only a small proportion of exposures exceed the action level proposed in British standards, and in many occupations, non-occupational sources are more important than those at work. The commonest occupational sources of WBV and occupations with particularly high exposures have been identified, providing a basis for targeting future control activities.

Adolescent↗
PubMed2000

Validity of self reported occupational exposures to hand transmitted and whole body vibration.

OBJECTIVES: To assess the accuracy with which workers report their exposure to occupational sources of hand transmitted (HTV) and whole body vibration (WBV). METHODS: 179 Workers from various jobs involving exposure to HTV or WBV completed a self administered questionnaire about sources of occupational exposure to vibration in the past week. They were then observed at work over 1 hour, after which they completed a second questionnaire concerning their exposures during this observation period. The feasibility of reported sources of exposure during the past week was examined by questioning managers and by inspection of tools and machines in the workplace. The accuracy of reported sources and durations of exposure in the 1 hour period were assessed relative to what had been observed. RESULTS: The feasibility of exposure in the previous week was confirmed for 97% of subjects who reported exposure to HTV, and for 93% of subjects who reported exposure to WBV. The individual sources of exposure reported were generally plausible, but occupational use of cars was substantially overreported, possibly because of confusion with their use in travel to and from work. The accuracy of exposures reported during the observation period was generally high, but some sources of HTV were confused-for example, nailing and stapling guns reported as riveting hammers, and hammer drills not distinguished from other sorts of drill. Workers overestimated their duration of exposure to HTV by a median factor of 2.5 (interquartile range (IQR) 1.6-5.9), but estimated durations of exposure were more accurate when the exposure was relatively continuous rather than for intermittent short periods. Reported durations of exposure to WBV were generally accurate (median ratio of reported to observed time 1.1, IQR 1.0-1.2). CONCLUSIONS: Sources of recent occupational exposure to vibration seem to be reported with reasonable accuracy, but durations of exposure to HTV are systematically overestimated, particularly when the exposure is intermittent and for short periods. This raises the possibility that dose-response relations may have been biased in some of the studies on which exposure standards might be based, and that the levels in currently proposed standards may be too high. Future studies should pay attention to this source of error during data collection.

Adolescent↗
PubMed2000

Prevalence of Raynaud's phenomenon in Great Britain and its relation to hand transmitted vibration: a national postal survey.

OBJECTIVES: To assess the prevalence of Raynaud's phenomenon in the general population of Great Britain and to estimate the proportion and number of cases attributable to hand transmitted vibration (HTV). METHODS: A questionnaire was posted to a random sample of 22,194 adults of working age. Information was collected on the lifetime prevalence of finger blanching, smoking habits, and occupational and leisure time exposures to HTV. Associations with risk factors were explored by logistic regression, with odds ratios converted into prevalence ratios (PRs). RESULTS: Among the 12 907 respondents, 1835 (14.2%) reported finger blanching at some time, including 1529 (11. 8%) in whom symptoms were induced by cold, and 597 (4.6%) in whom the blanched area was also clearly demarcated. Prevalences were higher in women than men. Around one fifth of cases (2% of respondents) had consulted a doctor about their symptoms. By comparison with men who had never been exposed to HTV, the PR for cold induced blanching in those exposed only at work was 2.0 (95% CI 1.7 to 2.3), and in men exposed both at work and in leisure it was 2. 5 (95% CI 2.1 to 3.1). Higher risks were found in men who consulted a doctor about cold induced blanching, among whom 37.6% of cases were estimated to arise from exposure to HTV. The estimated number of cases attributable to HTV nationally was 222 000 in men who reported extensive blanching (blanching affecting at least eight of the digits or 15 phalanges). Similar patterns of risk were found in women, but the attributable proportion was much lower (5.3% in cases consulting a doctor). CONCLUSIONS: Raynaud's phenomenon is common in the general population. Many cases are attributable to HTV, especially in men, emphasising the public health importance of this common occupational hazard.

Adolescent↗
PubMed2000

Personal exposures of children to nitrogen dioxide relative to concentrations in outdoor air.

OBJECTIVES: To investigate the relation between fluctuations in personal exposure to nitrogen dioxide (NO(2)) in school children and changes in outdoor NO(2) concentrations. METHODS: 114 Asthmatic school children aged 7-12 years were recruited from the Southampton area. Weekly average personal exposures to NO(2) were measured over a 13 month period with passive diffusion tubes. At the same time, outdoor NO(2) concentrations were monitored at a fixed site in the centre of Southampton. Correlations between weekly personal exposures and mean outdoor concentrations during the same periods were examined. RESULTS: Mean duration of follow up was 32 weeks. Measurements of weekly mean personal NO(2) exposures were generally low and ranged from 2.47 to 1751 [corrected] micrograms/m(3) with a geometric mean of 60 [corrected] micrograms/m(3). Substantial variation in personal exposures occurred between children and more especially within individual children from week to week. Daily outdoor concentrations of NO(2) ranged from 15.2 to 105.2 [corrected] micrograms/m(3), with a geometric mean of 43.4 [corrected] micrograms/m(3). There was no evidence of seasonal variation in outdoor concentrations. No significant correlation was found between each child's weekly mean personal exposures to NO(2) and mean outdoor concentrations for the corresponding periods. CONCLUSION: At low outdoor NO(2) concentrations, fluctuations in NO(2) in outdoor air as measured at a central monitoring station do not contribute importantly to variations in personal exposure when averaged over a week.

Air Pollution↗
PubMed2000

Personal exposure to nitrogen dioxide and risk of airflow obstruction in asthmatic children with upper respiratory infection.

BACKGROUND: Several studies have linked air pollution by nitrogen dioxide (NO(2)) with increased hospital admissions for asthma in children. Exacerbations of asthma in children are often precipitated by upper respiratory infections. It is therefore possible that NO(2) increases the risk of airways obstruction when asthmatic children develop upper respiratory infections. METHODS: To test this hypothesis a sample of 114 asthmatic children aged 7-12 years were followed for a total of up to 13 months. Probable upper respiratory infections were identified by consensus review of daily symptom diaries, and episodes of airways obstruction from serial records of peak expiratory flow (PEF). Personal exposures to NO(2) were measured with Palmes tubes that were changed weekly. Generalised estimating equations were used to assess the relative risk (RR) of an asthmatic exacerbation starting within seven days of an upper respiratory infection according to estimated NO(2) exposure during the one week period from two days before to four days after the onset of the infection. RESULTS: The children were followed for an average of 34 weeks during which 318 upper respiratory infections and 224 episodes of reduced PEF were diagnosed. PEF episodes were much more likely to occur in the seven days following the onset of an upper respiratory infection than at other times. Estimated exposures to NO(2) at the time of infections were generally low (geometric mean 10.6 microg/m(3)). Compared with exposures of < or = 8 microg/m(3), exposures of >28 microg/m(3) were associated with a RR of 1.9 (95% confidence interval 1.1 to 3.4) for the development of an asthmatic episode within seven days of an infection. CONCLUSIONS: The findings give some support to the hypothesis that NO(2) increases the risk of asthmatic exacerbations following respiratory infections, even at relatively low levels of exposure. Further studies in populations with higher exposures would be useful.

Air Pollutants↗
PubMed2000

Occupational lifting is associated with hip osteoarthritis: a Japanese case-control study.

OBJECTIVE: Hip osteoarthritis (OA) is a frequent cause of pain and disability in Western countries, but the disorder is less common in Japan. A case-control study in Britain found obesity, hip injury, and occupational lifting to be associated with hip OA among men and women. However, there are few epidemiological studies concerning factors associated with hip OA in Japan. We performed a comparable case-control study of the disorder in Japan, and contrasted the findings with those from Britain. METHODS: The study was carried out in 2 health districts in Wakayama Prefecture, Japan. Cases were men and women aged > or = 45 years listed for total hip arthroplasty due to OA over one year, and who did not have an established cause of secondary OA (e.g., rheumatoid arthritis, ankylosing spondylitis). For each case, a control was selected randomly from the general population and was individually matched to the case for age, sex, and district of residence. Cases and controls were interviewed with a structured questionnaire about medical history, physical activity, socioeconomic factors, and occupation. Measurements were made of height and weight. RESULTS: One hundred fourteen cases (103 women, 11 men) were compared with 114 controls. We found no relationship between obesity and hip OA (OR = 1.0, 95% CI 0.5-1.9; highest vs lowest thirds of distribution of body mass index). There was, however, a statistically significant association between occupational lifting and hip OA, such that regular lifting of 25 kg in the individual's first job (OR = 3.6, 95% CI 1.3-9.7) or of 50 kg in their main job (OR = 4.0, 95% CI 1.1-14.2) was associated with increased risk of hip OA. These associations remained after adjustment for potential confounding variables. In contrast, those subjects who spent > 2 h each day sitting during their first job were significantly less likely to have the disorder (crude OR = 0.5, 95% CI 0.3-0.9). This association also remained statistically significant after adjustment for potential risk factors. CONCLUSION: Our findings support the hypothesis that occupational physical activity, particularly the lifting of very heavy loads in the workplace at regular intervals, predisposes to hip OA in both Britain and Japan. The lack of association between obesity or hand involvement and hip OA in Japan suggests that the contribution of constitutional and mechanical risk factors to this disorder might differ in different populations. However, attention to manual handling in the workplace would appear an important aspect of preventive strategies against hip OA in Western and Oriental populations.

Aged↗
PubMed1999

Prevalence and risk factors for latex allergy: a cross sectional study in a United Kingdom hospital.

OBJECTIVES: To determine the prevalence and risk factors for symptoms related to gloves, and the relation between symptoms and immunological evidence of type 1 hypersensitivity to latex in a United Kingdom health care setting. METHODS: A cross sectional survey was carried out among 773 employees at a British hospital. A self administered questionnaire was used to collect information about symptoms related to gloves and associated risk factors in a sample of hospital staff who were likely to use gloves at work. All of those who reported symptoms suggestive of type 1 hypersensitivity were invited for skin prick testing and measurement of specific IgE to latex (RAST). RESULTS: Among the 372 responders, symptoms related to gloves were common, 49% reported redness or itching of the hands, 14% reported urticaria, and 6% reported chest tightness. However, the frequency of positive skin prick tests and RASTs was surprisingly low (only two subjects tested positive). CONCLUSIONS: These findings indicate the need for caution in the interpretation of symptoms related to gloves even when they seem to suggest type 1 hypersensitivity.

Adult↗
PubMed1999

Respiratory symptoms in older people and use of domestic gas appliances.

BACKGROUND: Studies in children and young women have indicated an increased risk of respiratory illness in association with the use of domestic gas appliances, possibly caused by oxides of nitrogen generated when gas is burned. It is not known whether risks are similarly increased in older subjects. METHODS: A questionnaire about respiratory symptoms in the past year and potential risk factors for respiratory disease was mailed to 6000 men and women aged 65 years and older who were selected at random from the lists of general practices in North Bristol, UK. Associations between symptoms and the use of gas appliances were examined by logistic regression with adjustment for age, sex, social class, and smoking habits. RESULTS: Questionnaires were completed by 4792 (80%) of those mailed. The most common symptoms were exercise induced breathlessness, wheeze, or chest tightness (51%); wheeze (27%); morning phlegm (20%); and daytime breathlessness at rest (19%). In an analysis that included all subjects only weak associations were found with use of gas appliances, odds ratios all being 1.2 or less. The risks associated with use of a gas hob tended to be higher in women, with odds ratios of 1.36 (95% CI 1.01 to 1.83) for wheeze and 1.33 (95% CI 0.56 to 3.17) for morning chest tightness, but were lower than had been reported previously in younger women. CONCLUSION: The absence of stronger associations cannot readily be explained by bias or confounding. Gas cookers and fires are unlikely to be an important cause of respiratory illness in the elderly. If they do cause such illness, the largest risks are likely to be in women who use gas hobs.

Aged↗