Post-occupational health surveillance of asbestos workers.

BACKGROUND: Italian law requires an extensive health surveillance of workers after cessation of their employment status in the case of occupational exposure to carcinogens, including asbestos. Nonetheless, Italian law does not specify the timeframe of these clinical checks, nor who has financial and organizational responsibility for this surveillance. A literature search confirmed a lack of consensus around the objectives and methods to follow up workers with past occupational exposure to asbestos. OBJECTIVES: To develop an updated evidence-based methodology for an appropriate health surveillance programme. METHODS: We present an overview of the field experience developed by the Veneto Region from 2000 to 2011, and new studies that could contribute to establishing a national policy for the medical surveillance of workers with past asbestos exposure. RESULTS: There were three specific topics: (1) definition of a reliable method to identify asbestos workers (through multiple sources and procedures that meet current confidentiality regulations); (2) detection of asbestos fibres in biological media (to support the etiological diagnosis of asbestos-related diseases); (3) creation of a national protocol of health surveillance (through the assessment of policies developed by other Regions in this field, and recruiting from these regions a cohort of past-exposed workers: the epidemiological study should offer relevant suggestions for specific surveillance approaches, based on either estimated cumulative asbestos exposure or detection of x-ray patterns of pleural plaques and/or asbestosis). CONCLUSIONS: These studies will support the Regions in setting up health care policies directed at workers with past asbestos exposure.

[Feasibility of a screening programme for lung cancer among workers previously heavily exposed to asbestos]. / Valutazione di un programma per la diagnosi precoce di cancro polmonare negli ex esposti ad asbesto.

BACKGROUND: We evaluated the feasibility and costs of a screening programme with spiral CT for the early diagnosis of lung cancer among workers previously heavily exposed to asbestos. METHODS: We invited 2000 workers, 1165 (58%) of whom accepted. Women and individuals with incomplete information were excluded; 1119 subjects (mean age, 57 years) entered the main analysis. Subjects with non-calcified lung nodules and/or dubious pleural plagues (No=338) entered a post-screening diagnostic protocol based on radiological follow-up. RESULTS: Twenty-five biopsies were performed (13 pulmonary, 9 pleural, 3 combined) revealed 5 cases of lung cancer (including 1 in stage IA). The positive predictive value of the screening test was low (31%) despite its known high sensitivity (100%) and specificity (99%). Incidence of lung cancer was similar to that registered among male residents of the Veneto Region aged 55 to 59 years. The cost of the programme was Euro 1,000 per screened subject and Euro 245,000 per diagnosis (total cost, Euro 1,181,310). The total radiation dose administered to healthy subjects was about 1,100 mSv (220 mSv per lung cancer diagnosis). CONCLUSIONS: This screening programme was ineffective due to the low participation rate, the small number of diagnoses, low predictive value, and high costs.

[Occupational injuries and sickness absence: association with job demand, decision latitude, and life style in 2174 workers in the Veneto Region]. / Infortuni sul lavoro e assenze dal lavoro per malattia: associazioni con carico lavorativo, autonomia decisionale e stili di vita in 2174 lavoratori del veneto.

BACKGROUND: Stress was the most frequent (26,9%) health problem reported in a survey on the perception of working and health conditions in 5000 workers in the Veneto Region. OBJECTIVES: The aim of the study was to investigate in the Veneto Region the association between occupational stress and events occurred in the previous 12 months: occupational accidents, or sickness absence for 10 or more consecutive days. METHODS: Perceived occupational stress is correlated, according to Karasek's model, to high job demand (JD) and low decision latitude (DL). Using Karasek's questionnaire (to which questions on smoking and alcohol consumption were added), we examined 2174 subjects working in 30 companies with between 10 and 500 employees, who belonged to the occupational categories of industry and services that are more prevalent in the Veneto Region. The questionnaire was administered by the occupational physician during health surveillance. The subjects were classified on the basis of current exposure to psychosocial factors or, for subjects reporting an event, their exposure at that time. We identified the tertiles of JD and DL; data were submitted to the analysis of multiple logistic regression, estimating odds ratio (OR) and 95% confidence interval (CI). The population attributable risk (PAR) was calculated using the formula (pc (OR-1)/OR), where pc is the fraction of exposed cases. RESULTS: An elevated risk of occupational accidents was found in subjects with regular consumption of alcohol (OR = 2.0; IC = 1.2-3.5), in smokers smoking 10-20 (2.3; 1.3-3.8) or >20 cigarettes/day (3.8; 1.8-7.9), in the highest tertile of JD (2.29; 1.35-3.89) and in the lowest tertile of DL (1.6; 1.0-2.6). PAR was 37.6% for occupational factors (high JD and low DL), 44.5%for non-occupational factors (cigarette smoking and alcohol consumption), and 82.1% overall. The risk of sickness absence increased in subjects smoking 10-20 cigarettes (1.63 = 1.1-2.40), in the highest tertile of JD (1.5; 1.0-2.2) and in the lowest tertile of DL (1.6; 1.1-2.2). PAR was 26.1% for occupational factors (high JD and low DL), 7.6% for non-occupational factors (smoking), and 30.4% overall. While the risk of sick absence increased mainly with the reduction of DL, the risk of occupational accidents increased with increasing JD and, to a lesser extent, with decreasing DL. The current approach to accident prevention is based only on technical and administrative aspects, in spite of the fact that 80% of accidents are not attributable to malfunctioning of machinery. Injury prevention should address technical, personal and psychosocial risk factors together as a whole.

[Association between causes of lNPS compensated disability and occupational category (Veneto Region, 1994-2002): a surveillance method for occupational diseases?]. / Associazione tra causa di invalidita pensionabile INPS e comparto lavorativo (Veneto, 1994-2002): un metodo di sorveglianza delle malattie professionali?

BACKGROUND: According to Italian law, workers are insured against disability through the National Social Security Institute (INPS), whose records contain information on diseases causing disability and occupational histories. OBJECTIVES: Using the INPS data, our objective was to identify any excess risk of disabling diseases in relation to the occupational categories. METHODS: Insurance covers all private sector employees, a small proportion of public sector employees, agricultural labourers, domestic workers, self-employed workers (craftsmen, commercial dealers,farmers), and few other occupational categories. For each insured worker, a database was created containing registry data, occupational history and, for compensated workers, the disease code, for each year from 1994 to 2002. A cohort study design was adopted, in which references were self-employed workers (with mixed exposure) to whom different categories of employees in agriculture, industry, crafts, and services were compared. Data were analyzed by means of Poisson regression, estimating the Incidence Rate Ratio (IRR) and confidence interval (CI) at 99.99%, instead of 95%, in order to set the threshold of error for the entire study at 0.05. RESULTS: In the construction industry there were significantly high risks of disability in both industry and crafts for tumours (industry: IRR = 2.07; IC = 1. 67-2.57; crafts: 2.57; 1.89-3.18), circulatory disorders (industry: IRR = 2.24; IC = 1.65-3.04; crafts.: 3.06; 2.16-4.32), and bone and joint diseases (industry. IRR = 5.0; IC = 3.15-7.94; crafts: 6.58; 5.04-8.59). CONCLUSIONS: The advantage of this approach is to recruit a large number of subjects at limited cost. The procedure here proposed is a mainly exploratory approach aimed at establishing new study hypotheses: disability, in fact, is acknowledged by INPS when its cause is not occupational according to the current literature.