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Biomedical subjects

D Coggon

Publications and source records attributed to D Coggon.

At least 109 records · Page 6Linked to original sources
PubMed1996

Upper aerodigestive cancer in battery manufacturers and steel workers exposed to mineral acid mists.

OBJECTIVE: To assess the risk of cancer from inhalation of mineral acid mists. METHODS: A cohort study and nested case-control study of upper aerodigestive tumours were carried out in men employed since 1950 at two battery plants and two steel works in Britain. The cohort was identified from personnel records and included 2678 men with definite exposure to acid mists (mainly sulphuric acid), 367 with possible exposure, and 1356 who were unexposed. Mortality was compared with that in the national population by the person-years method. Cases of upper aerodigestive cancer were identified from death certificates and cancer registrations, and their exposure to acids was compared with that of age matched controls (five per case) from the same plant by conditional logistic regression. RESULTS: In follow up to 31 December 1993, 93% of men were traced, including 1277 who had died. Among the men definitely exposed to acid mists, overall mortality was less than in the national population (standardised mortality ratio (SMR) 0.92, 95% confidence interval (95% CI) 0.85-0.98) as was mortality from all cancers (SMR 0.92, 95% CI 0.79-1.05) and specifically from cancer of the larynx (SMR 0.48, 95% CI 0.01-2.70) and lung (SMR 0.98, 95% CI 0.78-1.22). A total of 15 incident or fatal cases of upper aerodigestive cancer were identified during follow up. When these men were compared with controls, risk was moderately increased in those who had worked for at least five years in jobs entailing exposures to sulphuric or hydrochloric acid in excess of 1 mg/m3 (OR 2.0, 95% CI 0.4-10). CONCLUSIONS: These findings are consistent with those from other studies which have indicated a hazard of upper aerodigestive cancer from acid mists. However, they indicate that any risk from exposures to sulphuric and hydrochloric acid below 1 mg/m3 is small.

Aerosols↗
PubMed1996

Work related respiratory symptoms in radiographers.

OBJECTIVE: To determine the prevalence of work related symptoms among radiographers compared with a control group of physiotherapists. METHOD: A postal questionnaire was used to collect information from radiographers and physiotherapists who registered in the United Kingdom during 1985-9. RESULTS: Satisfactory questionnaires were returned by 2354 (65%) of the radiographers and 3048 (69%) of the physiotherapists. There was a clear excess of work related symptoms among the radiographers. In particular, they were more likely to complain of symptoms that were worse at work, mouth soreness, sore, itchy, or runny eyes, persistent blocked nose, persistent itchy nose or sneezing, sore throat, headache, and of lower respiratory tract symptoms, which were also worse on workdays. These symptoms were associated particularly with the use of automatic processing machines. 235 radiographers gave a history of wheeze or chest tightness that had been worse at work or on days when at work. CONCLUSIONS: Work related symptoms suggesting irritation of the eyes and upper airways were more common in radiographers than controls, and may be related to exposure to x ray film processing chemicals. Men and women who reported work related wheeze or chest tightness will be followed up in more detail to assess the prevalence of occupational asthma in the cohort.

Adult↗
PubMed1996

Exposure to styrene and mortality from nonmalignant respiratory diseases.

A cohort of 34,560 men and 6128 women employed in 660 European factories manufacturing reinforced plastic products, followed up originally to assess the risk of cancer, was used to assess the risk of non-malignant respiratory diseases associated with exposure to styrene. Mortality from pneumonia was associated with intensity of exposure to styrene, but this may have been due to chance. Mortality from bronchitis, emphysema, and asthma was not associated with styrene exposure.

Cohort Studies↗
PubMed1996

Does dietary intake of vitamins C and E influence lung function in older people?

Antioxidants in the lung have a protective role against oxidative damage. We have investigated whether dietary antioxidant intake in elderly people is related to lung function. Dietary intakes of ascorbic acid (vitamin C) and alpha-tocopherol (vitamin E) and lung function were assessed in 178 men and women aged 70 to 96 yr selected on the basis of reported respiratory symptoms. After adjustment for age, gender, height, smoking habits, total energy intake, and vitamin C intake by multiple linear regression, vitamin E intake was significantly associated with FEV1 p = 0.012 and FVC p = 0.003. There was no evidence of any interaction between vitamin E intake and current tobacco smoking as determinants of lung function. For every extra milligram increase in vitamin E in the daily diet, FEV1 increased by an estimated 42 ml and FVC by an estimated 54 ml. These results suggest that dietary intake of vitamin E may influence lung function in the elderly, but food frequency questionnaires in this study were not of sufficient sensitivity to explore this hypothesis further.

Aged↗
PubMed1996

Exposure to styrene and mortality from nonmalignant diseases of the genitourinary system.

OBJECTIVES: A historical cohort study was carried out to investigate mortality from nonmalignant diseases of the genitourinary system among workers in the reinforced plastics industry, where high workroom concentrations of styrene are encountered. METHODS: The external comparisons in this report were based on an average of 12.6 years of retrospective follow-up of 35 443 workers who were first employed in the reinforced plastics industry during 1945-1991 and were known to have been exposed to styrene in their work. For the internal comparisons, 2641 subjects with incomplete occupational histories were excluded, leaving 32 802 subjects. Previous individual exposure histories to styrene were reconstructed through job histories and environmental and biological monitoring data. RESULTS: Mortality from nonmalignant diseases of the genitourinary system (N = 20) was associated with average exposure to styrene (P for trend 0.05). Weaker increasing trends in risk were seen for time since first exposure and cumulative exposure, while no increase was identified for duration of exposure. There was a significant increasing trend in mortality from nephritis and nephrosis (N = 5), associated with an increasing average level of exposure to styrene (P for trend 0.03). No clear trend was observed for time since first exposure, duration of exposure, or cumulative exposure. CONCLUSIONS: In this large cohort study of workers exposed to styrene, mortality from nonmalignant diseases of the genitourinary system increased as the average intensity of exposure increased. This finding indicates that other data should be scrutinized.

Air Pollutants, Occupational↗
PubMed1996

Water fluoridation and osteoporotic fracture.

Osteoporotic fractures constitute a major public health problem. These fractures typically occur at the hip, spine and distal forearm. Their pathogenesis is heterogeneous, with contributions from both bone strength and trauma. Water fluoridation has been widely proposed for its dental health benefits, but concerns have been raised about the balance of skeletal risks and benefits of this measure. Fluoride has potent effects on bone cell function, bone structure and bone strength. These effects are mediated by the incorporation of fluoride ions in bone crystals to form fluoroapatite, and through an increase in osteoblast activity. It is believed that a minimum serum fluoride level of 100 ng/ml must be achieved before osteoblasts will be stimulated. Serum levels associated with drinking water fluoridated to 1 ppm are usually several times lower than this value, but may reach this threshold at concentrations of 4 ppm in the drinking water. Animal studies suggest no effect of low-level (0-3 ppm) fluoride intake on bone strength, but a possible decrease at higher levels. Sodium fluoride has been used to treat established osteoporosis for nearly 30 years. Recent trials of this agent, prescribed at high doses, have suggested that despite a marked increase in bone mineral density, there is no concomitant reduction in vertebral fracture incidence. Furthermore, the increase in bone density at the lumbar spine may be achieved at the expense of bone mineral in the peripheral cortical skeleton. As a consequence, high dose sodium fluoride (80 mg daily) is not currently used to treat osteoporosis. At lower doses, recent trials have suggested a beneficial effect on both bone density and fracture. The majority of epidemiological evidence regarding the effect of fluoridated drinking water on hip fracture incidence is based on ecological comparisons. Although one Finnish study suggested that hip fracture rates in a town with fluoridated water were lower than those in a matching town without fluoride, a later study failed to show differences. Ecological studies from the United States and Great Britain have, if anything, revealed a weak positive association between water fluoride concentration and hip fracture incidence. Two studies examining hip fracture rates before and after fluoridation yielded discordant results, and are complicated by underlying time trends in hip fracture incidence. Only two studies have attempted to examine the relation between water fluoride concentration and fracture risk at an individual level. In one of these, women in a high fluoride community had double the fracture risk of women in a low fluoride community. In the other, there was no relationship between years of fluoride exposure and incidence of spine or non-spine fractures. In conclusion, the epidemiological evidence relating water fluoridation to hip fracture is based upon ecological comparisons and is inconclusive. However, several studies suggest the possibility of a weak adverse effect, which warrants further exploration. Data on the relationship between fluoride intake and hip fracture risk at the individual level, and data relating fluoridation to bone mineral density are required. Until these become available, the burden of evidence suggesting that fluoridation might be a risk factor for hip fracture is weak and not sufficient to retard the progress of the water fluoridation programme.

Aged↗
PubMed1996

Generalized osteoarthritis in women: pattern of joint involvement and approaches to definition for epidemiological studies.

OBJECTIVE: To ascertain whether clustering between joint sites in osteoarthritis (OA) is more common than would be expected simply from the rising prevalence of the disorder with age, and to explore a definition of generalized OA (GOA) by determining the pattern of joint group involvement, in a population sample of peri and postmenopausal women. METHODS: Radiographs of the hands, knees, and hips were obtained in a population sample of 702 women aged 45 to 64 years. Distal interphalangeal, proximal interphalangeal, carpometacarpal, knee, and hip OA were assessed using the Kellgren-Lawrence grading system. Logistic regression was used to test for overall clustering of OA between joint sites, and log linear models were used to study the patterns of association between different sites. RESULTS: Multiple involvement of the 5 joint groups studied occurred significantly more frequently than could be expected by chance alone (chi 2 = 52.3, df = 5, p < 0.001), and this clustering remained significant after age adjustment (chi 2 = 26.1, df = 5, p < 0.001). Thresholds could be defined for the number of involved joint groups that distinguished a polyarticular subset of OA. These thresholds varied with age and the radiographic cutoff at which OA was assigned. Thus, for grade 2+ disease, GOA could be defined by involvement of 2 or more joint groups at age 45-47 years, but required involvement of all 5 joint groups at age 60-64 years. Symmetry within joint groups was the most pronounced feature in the pattern of joint involvement in the sample as a whole, with associations between different joint groups being substantially weaker than those for symmetrical bilateral involvement of a particular joint. CONCLUSION: There is a clear tendency towards polyarticular OA among women aged 45-64 years. However, there is no single threshold number of joint sites that can be used to define GOA. The pattern of joint involvement in OA is primarily symmetrical, and this pattern strongly suggests a systemic etiology in this subset of postmenopausal women.

Arthrography↗
PubMed1995

Questionnaire based exposure assessment methods.

In environmental epidemiological studies, questionnaires may be the method of choice for assessing exposure because no other source of information is available, or because they provide the most efficient study design, allowing a larger study size and greater statistical power than would be possible with other more accurate measurement techniques. Problems may arise from a lack of content validity (the questionnaire does not cover all sources of exposure to the hazard of interest) or criterion validity (e.g., through inaccurate recall or misunderstanding of questions). Methods for validating questionnaires are described. The usefulness of validated 'standard' questionnaires is discussed, particularly in regard to comparison of exposure patterns in various populations studied separately. It is stressed that the validity of standard questionnaires should not be automatically assumed when they are applied to populations other than those in which they have been tested.

Environmental Exposure↗
PubMed1995

Human papillomavirus DNA and TP53 mutations in lung cancers from butchers.

To investigate whether the high frequency of human papillomavirus infection in butchers may be linked to their higher than average incidence of lung cancer, we have examined lung cancers from 40 butchers and 26 controls for the presence of DNA from both HPV type 7, which is found almost uniquely in hand warts from butchers and fishermen, and for those HPV types associated with laryngeal and genital cancers. No HPV 7, and only a low frequency of HPV DNA was found, suggesting that HPV infection does not make an important contribution to the elevated levels of lung cancer in meat handlers. In addition, the frequency of p53 mutation was shown to be slightly lower than previously reported in lung cancers.

Adult↗
PubMed1995

Management of sharps injuries and contamination incidents in health care workers: an audit in the Wessex and Oxford regions.

Fifteen NHS occupational health departments from the Wessex and Oxford regions took part in an audit of the management of sharps injuries and contamination incidents. Data were collected prospectively for a series of 1102 incidents notified over a nine-month period. The rates of notified incidents for each department ranged from 9 to 44 incidents per 1000 staff members per year. The proportion of injured employees who were naturally immune to hepatitis B or had completed a full course of vaccination against the infection ranged from 57 to 83%, with the main shortfall occurring in ancillary workers. Some departments rarely stored source serum, while others did so in the majority of cases. The proportion of cases where the injured person was known to have had hepatitis B antibody levels > 100 IU/l within the past 12 months, or underwent immediate antibody assessment or had an immediate vaccination against hepatitis B varied from 26 to 97%, with a median of 68%. On the basis of these findings, the audit group has set targets against which performance will be re-assessed in a follow-up exercise.

Accidents, Occupational↗
PubMed1995

Osteoarthritis of the hip joint and acetabular dysplasia in women.

OBJECTIVE: To investigate the suggestion that osteoarthritis (OA) of the hip joint is often caused by subclinical acetabular dysplasia among elderly British women. METHODS: We examined 393 hip joints from the radiographs of a sample of women aged 60-75 years undergoing intravenous urography. Acetabular dysplasia was assessed using measurements of the centre-edge (CE) angle and acetabular depth (AD), which are both reduced in this condition. OA was assessed using an overall grade based on the Kellgren and Lawrence system and by measurement of minimum joint space (MJS). RESULTS: MJS was the more repeatable measure of OA, and showed a strong correlation with overall grade (Spearman rank correlation coefficient rs = -0.61, p < 0.01). MJS was significantly negatively correlated with CE angle (Pearson correlation coefficient r = -0.25, p < 0.001) and AD (r = -0.11, p < 0.05). Consistent with these findings, there was a weak but significant positive correlation between overall grade of OA and one of the two measures (CE angle) of acetabular dysplasia. CONCLUSIONS: These results do not support the hypothesis that mild degrees of acetabular dysplasia account for a substantial proportion of hip OA in elderly women. Changes in hip joint geometry as a result of OA may be responsible for the weak negative association observed.

Aged↗
PubMed1995

Low back pain in Hong Kong: prevalence and characteristics compared with Britain.

STUDY OBJECTIVE: To compare the prevalence of low back pain and associated disability in Hong Kong with that in Britain, and to explore whether differences could be explained by certain known risk factors. DESIGN: A cross sectional survey with information collected at interview. Findings were compared with those from an earlier survey in Britain. SETTING: Two housing blocks in Hong Kong. SUBJECTS: Altogether 288 men and 364 women aged 18 years or older, who were resident in the two housing blocks and agreed to interview (response rate = 80%). MAIN RESULTS: Thirty nine per cent (95% confidence interval (CI) 34%, 44%) of interviewees reported having had low back pain at some time, and 21% (95% CI 18%, 25%) had had low back pain in the past 12 months. After standardisation for age and sex, all of the back symptoms examined were substantially less common in Hong Kong than in Britain. The one year period prevalence of low back pain was associated with occupational lifting (in both sexes) and with tall stature (in men only). Subjects tended to carry out less heavy lifting at work and to be shorter than participants in the earlier British study but these differences did not completely explain their lower prevalence of back pain. CONCLUSIONS: The findings indicate a lower prevalence of back symptoms in Hong Kong than Britain that is partly explained by differences in stature and occupational lifting. In addition, Hong Kong people may have a higher threshold for reporting symptoms, or they may differ in their exposure to other, unrecognised risk factors.

Adolescent↗
PubMed1995

Differences in occupational mortality from pleural cancer, peritoneal cancer, and asbestosis.

OBJECTIVE: To assess whether the increased risk of disease related to asbestos in occupations from the construction and engineering industries applies equally to pleural cancer, peritoneal cancer, and asbestosis. METHODS: Analysis was based on deaths among men aged 20-74 in England and Wales during 1979-80 and 1982-90. (n = 1,656,096). Information about cause of death and the last full time occupation of decedents was derived from death certificates. Proportional mortality ratios (PMRs) by occupation were calculated for each of pleural cancer, peritoneal cancer, and asbestosis. RESULTS: Altogether, 2848 deaths were attributed to cancer of the pleura, 362 to cancer of the peritoneum, and 281 to asbestosis. When occupations were ranked according to PMRs from these diseases, striking differences were found. The category of construction workers which included laggers had the highest mortality from peritoneal cancer (PMR 990, 64 deaths), but a PMR of only 160 (77 deaths) for pleural cancer. In contrast, several occupations with much higher mortality from pleural tumours had no excess of peritoneal cancer. PMRs for asbestosis related more closely to those for peritoneal than pleural cancer. CONCLUSIONS: These findings suggest that the exposure-response relations for diseases related to asbestos are not all linear, and that risks of pleural mesothelioma may be underestimated by simple extrapolation from observations in cohorts with heavy exposure.

Adult↗
PubMed1995

Mortality of butchers and cooks identified from the 1961 census of England and Wales.

OBJECTIVES: To explore a suspected hazard of lung cancer in butchers and cooks. METHODS: 4018 male butchers and 2062 male cooks were identified from the 1961 census of England and Wales. 4857 (79.9%) of these men were traced through the National Health Service Central Register, and 3518 deaths were recorded during follow up to the end of 1992. Mortality from lung cancer and other causes was compared with that of the general population by the person-years method. RESULTS: Mortality from all causes was significantly below that of the national population in both butchers (standardized mortality ratio (SMR) 0.94, 95% confidence interval (95% CI) 0.90-0.98) and cooks (SMR 0.89, 95% CI 0.84-0.95). When allowance was made for a latency of 20 years from entry to follow up, the deficit in butchers was reduced, but that in cooks persisted, and was largely explained by a shortfall of deaths from cancer and circulatory disease. Mortality from lung cancer was close to expectation in the butchers (SMR 1.01, 95% CI 0.90-1.13) and below expectation in the cooks (SMR 0.93, 95% CI 0.75-1.13). Cooks had increased mortality from cancers of the oral cavity (SMR 5.57) and pharynx (SMR 2.66). CONCLUSIONS: The findings provide no support for an occupational hazard of lung cancer in either butchers or cooks. The possibility of excess risk in sub-groups of these occupations cannot be discounted. The high rates of oral and pharyngeal cancer in cooks are probably a consequence of high alcohol consumption.

Cause of Death↗
PubMed1995

Manual handling activities and risk of low back pain in nurses.

OBJECTIVE: To investigate the risk factors for low back pain in hospital nurses, with particular emphasis on the role of specific nursing activities. METHODS: A cross sectional survey of 2405 nurses employed by a group of teaching hospitals was carried out. Self administered questionnaires were used to collect information about occupational activities, non-occupational risk factors for back symptoms, and history of low back pain. RESULTS: The overall response rate was 69%. Among 1616 women, the lifetime prevalence of back pain was 60% and the one year period prevalence 45%. 10% had been absent from work because of back pain for a cumulative period exceeding four weeks. Rates in men were generally similar to those in women. In women back pain during the previous 12 months was weakly associated with height, and was significantly more common in those who reported frequent non-musculoskeletal symptoms such as headache and low mood. After adjustment for height and non-musculoskeletal symptoms, significant associations were found with frequency of manually moving patients around on the bed, manually transferring patients between bed and chair, and manually lifting patients from the floor. In contrast, no clear increase in risk was found in relation to transfer of patients with canvas and poles, manually lifting patients in and out of the bath, or lifting patients with mechanical aids. Confirmation of these findings is now being sought in a prospective study of the same population. CONCLUSIONS: This study confirms that low back pain is highly prevalent among nurses and is associated with a high level of sickness absence. People who often report non-musculoskeletal symptoms were significantly more likely to report low back pain. Specific manual handling tasks were associated with an increased risk of back pain; however, no such association was found with mechanised patient transfers.

Adult↗
PubMed1995

Contrasting geographical distribution of mortality from pneumoconiosis and chronic bronchitis and emphysema in British coal miners.

To explore whether the characteristics of coal mine dust that predispose to chronic airways obstruction are the same as those associated with pneumoconiosis, mortality from the two disease was compared in coal miners in 22 counties of England and Wales during 1979-80 and 1982-90. The proportional mortality ratios (PMRs) for coal workers' pneumoconiosis varied from 135 (95% confidence interval (95% CI) 16-488) in Leicestershire to 3825 (95% CI 1538-7881) in South Glamorgan. The PMRs for chronic bronchitis and emphysema were consistently higher than those in other occupations, but showed much less geographical variation and did not correlate geographically with those for pneumoconiosis. These findings indicate that the pathogenetic mechanisms by which coal mine dust causes chronic bronchitis and emphysema depend on different features of the dust from those producing pneumoconiosis. Also, they suggest that current social security regulations in Britain, which require evidence of pneumoconiosis as a condition of compensation for chronic bronchitis and emphysema in coal miners, may discriminate unfairly against claimants from some regions.

Adult↗
PubMed1995

The influence of increased bronchial responsiveness, atopy, and serum IgE on decline in FEV1. A longitudinal study in the elderly.

We have performed a 4-yr prospective survey of the association of allergen skin test positivity, total serum immunoglobulin E (IgE), and bronchial responsiveness to methacholine, with longitudinal decline in FEV1, in subjects over 65 yr of age. In 1987, 324 subjects completed a respiratory questionnaire, and underwent measurement of FEV1 and FVC, methacholine challenge, skin prick testing (to Dermatophagoides pteronyssinus, cat fur, mixed grasses, and Aspergillus fumigatus) and estimation of total serum IgE. After an interval of 4 yr, 212 subjects were reexamined. The mean annual decline in FEV1 was significantly higher in males than in females, but was not significantly influenced by smoking habits defined at the start of the study. The relation of atopy (skin test reaction to allergen > or = 3 mm greater than saline control), increased bronchial responsiveness (PD20FEV1 < or = 6.4 mumoles methacholine) and serum IgE > 80 IU/ml, to annual decline in FEV1 was examined for each risk factor individually with adjustment for age, sex, height, and initial FEV1, by multiple linear regression. Both atopy and bronchial responsiveness were significantly associated with accelerated decline in FEV1. Elevated IgE was correlated with faster FEV1 decline in subjects who were current smokers at the start of the study. In a multiple regression model examining the mutually adjusted associations of all relevant variables with annual decline in FEV1, male sex was the most important predictor (B = 38.6 ml/yr, 95% Cl = 4.3, 72.9). Increased bronchial responsiveness also tended to be associated with accelerated decline in FEV1. In further analyses incorporating the same variables, but restricted to specific smoking categories, age was the only significant factor in the never-smokers, whereas both atopy (B = 44.5 ml/yr, 95% Cl = 3.8, 85.3) and increased bronchial responsiveness (B = 43.5 ml/yr, 95% Cl = 4.6, 82.3) were significant predictors of accelerated FEV1 decline in former and current smokers combined.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗