Antibodies against lytic and latent Kaposi's sarcoma-associated herpes virus antigens and lymphoma in the European EpiLymph case-control study.

BACKGROUND: Kaposi's sarcoma-associated herpes virus is associated with primary effusion lymphoma and multicentric Castleman's disease. METHODS: Seropositivity to lytic and latent Kaposi's sarcoma herpes virus (KSHV) antigens were examined in 2083 lymphomas and 2013 controls from six European countries. RESULTS: Antibodies against KSHV latent and lytic antigens were detectable in 4.5% and 3.4% of controls, respectively, and 3.6% of cases (P>0.05). The KSHV seropositivity was associated with splenic marginal zone lymphoma (SMZL) (odds ratio (OR)=4.11, 95% confidence interval (CI)=1.57-10.83) and multiple myeloma (OR=0.31, 95% CI=0.11-0.85). CONCLUSION: The KSHV is unlikely to contribute importantly to lymphomagenesis among immunocompetent subjects. However, the observed association with SMZL may underline a chronic antigen mechanism in its aetiology.

[Cancer incidence among petrochemical workers in the Porto Torres industrial area, 1990-2006]. / Incidenza di patologie neoplastiche nei lavoratori del complesso petrolchimico di Porto Torres, 1990-2006.

BACKGROUND: Various epidemiological studies explored cancer mortality and incidence among petrochemical workers. We followed up cancer incidence in a cohort of 5350 male petrochemical workers in the industrial area of Porto Torres (Sardinia, Italy). MATERIAL AND METHODS: The follow-up covered the period from 01/01/1990, when completeness of the cohort was certain and reference rates by the local Cancer Registry became available, up to 31/12/2006. Cohort members were subjects employed for six months or more in one of the chemical plants of the industrial area, alive as at 01/01/1990. Overall, a total of 81,392 person-years at risk were accumulated. The standardized incidence ratio (sir), as the ratio of observed to expected events, and its 95% confidence interval (CI) were calculated for all cancers and selected cancer sites, in the total cohort and in sub-cohorts of workers in plants where exposure to chemical agents evaluated in the IARC Monographs might have occurred. RESULTS: An increase in risk for all cancers was observed in the total cohort (596 cases; sir = 1.09; 95% CI 1.00-1.18), and it was highest for non-Hodgkin lymphoma (NHL, 26 cases: sir = 1.78; 95% CI 1.22-2.62). Risk for haemolymphatic cancer was highest in the sub-cohort of workers employed for 10 years or more, with a latency period of 20 years or longer, and among those employed in the manufacture and polymerization of vinyl chloride (VCM; all cancers, 51 cases: sir = 1.43; 95% CI 1.08-1.88; NHL, 4 cases: sir=4.06; 95% CI 1.64-10.0). Risk of haemolymphatic cancer was not significantly elevated in the sub-cohort potentially exposed to benzene. An excess risk of bladder cancer (RR = 1.46; 95% CI 1.09-1.96), but not of pleural cancer, was observed in the sub-cohort potentially exposed to asbestos. No significant increase in cancer risk was observed among workers potentially exposed to acrylonitrile, butadiene, or styrene. CONCLUSIONS: Our follow-up study of petrochemical workers showed an increase in risk for all cancers, and particularly NHL, apparently concentrated among workers potentially exposed to VCM

Prevalence of overweight and obesity in Sardinian adolescents.

BACKGROUND: To estimate the prevalence of overweight and obesity among adolescents in Sardinia and to examine the association with several biological and geographic factors. METHODOLOGY: A cross-sectional study was performed in 3,946 unselected adolescents (2,011 boys, 1,935 girls; aged 11-15 years) attending the public secondary schools in 33 Sardinian municipalities: 28 semi-rural, 5 urban, sub-grouped according to their geographic location (mountain, hillside and plain). Oversized children were measured and their BMI defined as being above normal values according to parameters provided by the International Obesity Task Force (IOFT) by Cole et al. (BMI for age > or = 95th percentile). Relative risk for overweight and obesity was calculated using Poisson regression analysis: risks associated to each covariate were reciprocally adjusted. The 95% confidence interval (CI) of the estimated risk was calculated using Wald's formula (RR, RR = log(n) beta +/- 1.96 se(beta)). MAIN FINDINGS: The overall prevalence rate found for overweight and obesity was 14.9% (95% C.I.: 13.7-16.1%) and 3.7% (95% C.I. 3.1-4.3%), respectively. Overweight rate showed no association with gender, whereas belonging to the female sex constituted a significant protection against obesity. Increasing age in the range 12-14 years was protective against both overweight and obesity in the whole sample. A similar finding however was not observed for obesity in girls or overweight in boys, when considered separately. Boys, but not girls, living in urban areas displayed a modest though significant 20% increase in overweight and a 40% decrease in obesity risk. Living in a mountainous area conveyed a 30% decrease in risk of overweight and a 50% decrease in risk of obesity, when compared to living on the plains and hillside combined. However, the small sample size of study subjects living in mountainous areas generated extremely wide 95% confidence intervals, thereby preventing the drawing of any significant conclusions. CONCLUSION: In comparison with other surveys performed by the IOFT, Sardinian adolescents show a low prevalence rate for oversize, emphasizing a marked discrepancy with the general north-south rising trend of oversize observed throughout Europe. Geographic location, aesthetic or other age related factors seem to exert a different gender-specific influence on overweight and obesity. SIGNIFICANCE: The present report is cross sectional and the consequences of overweight and obesity on individuals over time are not traceable. However, the outcome of the study suggests the need to implement suitable policies and public health programs leading to increased awareness.

Tobacco smoking, alcohol drinking and Hodgkin's lymphoma: a European multi-centre case-control study (EPILYMPH).

We analysed the effects of tobacco and alcohol in the aetiology of Hodgkin's lymphoma (HL), based on 340 cases and 2465 controls enrolled in Spain, France, Italy, Germany, Ireland and Czech Republic, between 1998 and 2004. Current smokers showed a significantly increased odds ratio (OR) of HL of 1.39 (95% confidence interval (CI) = 1.04-1.87). Analyses were also conducted separately for subjects younger than 35 years (179 cases) and for older subjects (161 cases). For subjects below age 35, no association was observed between tobacco and HL, whereas for older subjects, ever-smokers experienced a doubled risk of HL as compared to never smokers and the OR of HL for current smoking was 2.35 (95% CI = 1.52-3.61), with suggestion of a dose-response relationship. A protective effect of alcohol was observed in both age groups. The OR for ever-regular drinking was 0.58 (95% CI = 0.38-0.89) for younger subjects and 0.50 (95% CI = 0.34-0.74) for older subjects. There was no evidence of interaction between tobacco and alcohol. Our results are consistent with previous studies, suggesting a protective effect of alcohol on HL. An effect of tobacco was suggested for HL occurring in middle and late age, although this finding might have occurred by chance.

[Assessment of occupational noise exposure: methodology, measurement error, evaluation criteria]. / La valutazione dell'esposizione professionale al rumore procedure, errore di misura, criterio di decisione.

BACKGROUND: Occupational noise exposure can be monitored directly by personal sampling or indirectly, by area sampling. Personal sampling is performed using an integrating sound level meter, worn by the worker while performing his/her job. When area sampling is used, measurements need to be made in all locations where a typical worker stays while performing his/her tasks; the respective partial lengths of exposure need to be accurately monitored, and the time-weighted average sound level of the measured noise levels must be calculated. OBJECTIVES: Current regulations identify three different thresholds, corresponding to different types of action, but they do not propose any standard criteria to decide whether a threshold has been exceeded. Defining standard procedures to assess occupational noise exposure and identifying such thresholds is crucial. METHODS: Using empirical data collected in the field, the effects are illustrated of the number of sampling locations and of the partial lengths of exposure on area sampling measurements, and the effects of duration of noise exposure on both area and personal samplings. RESULTS: When dealing with area samplings, an accurate definition of both sampling locations and partial lengths of exposure is crucial. When arbitrary decisions are taken in selecting sampling locations and/or establishing partial lengths of exposure, spatial changes in noise level and operator' displacements while performing his/her tasks may affect results. Sampling for less than the duration of noise exposure is the major contributor to measurement error, particularly under conditions of unpredictable variation in noise level. In fact, as noise level in the non-monitored time fraction is unknown, measurement error cannot be determined. We estimate that, even under the most favorable circumstances, sampling should last not less than 40% of the duration of a given noise-generating occurrence, for repeated measurements to be dispersed within a range not wider than that generated by the instrumental error. Inter-daily variability is another important aspect in personal noise exposure evaluation. This is a general occurrence, whose effects cannot be controlled by simply considering weekly instead of daily exposures. Results of an investigation, covering about 60 different jobs within a primary aluminum plant, show an inter-daily variability in noise exposure greater than 5 dBA in about 75% of cases. CONCLUSIONS: Personal sampling, when correctly performed and covering the total duration of exposure, provides the most reliable result as it integrates noise over all locations where the worker actually stays while performing his/her tasks, and over the total length of time spent in each task. We propose extending personal sampling to the total duration of actual noise exposure as the standard procedure for monitoring daily personal noise exposure, and valid for the majority of work places. When the range of daily noise exposure includes one regulatory threshold, corresponding to a given type of action, we propose as a standard decision criterion to refer prudentially to the upper 95% confidence limit of the LEP,d arithmetic mean. Such criterion would allow to standardize procedures and decision methods, with the prospect of further improvements in the assessment of exposure to noise.

Occupational risk factors for the sporadic form of Creutzfeldt-Jakob disease.

Some case reports among European farmers and a few case-control studies suggested the hypothesis of an increased risk of the sporadic form of CJD (sCJD) associated with livestock farming or work as a butcher. Also, the discovery of the possibility of transmission of the disease via blood or by contact following corneal or dura madre transplant suggested that health occupations might also run higher sCJD risks. However, a meta-analysis of three case-control studies and a multicentre European study did not find any positive association between sCJD and health-related jobs or occupational contact with livestock, such as cattle and sheep, or animal products. To explore possible occupational risk factors for Creutzfeldt-Jakob disease (CJD), we used a publicly available US database including about 6 million deaths in 24 states during 1984-95. Cases were 636 deaths (300 men and 336 women) with CJD (ICD-9 code 046.1) as the underlying cause of death. Controls were 3,180 deaths randomly selected from among those who died from all other diseases except those affecting the central nervous system. CJD cases represented a wide variety of occupations (159) and industries (147). Among occupations and industries, for which previous reports suggested potential exposure to a transmissible spongiform encephalopathy (TSE) agent, the OR for CJD was significantly increased among butchers (OR = 6.8, 95% C.I. 1.5, 30.1, based on 4 cases and 3 controls), and persons working in offices of physicians (OR = 4.6, 95% C.I. 1.2, 17.6 based on 5 cases and 4 controls). Nine other occupations and seven other industries, for which no previous suggestion existed in the literature, also showed significant associations. Overall, our results suggest that occupational exposures are not an important source of sCJD infection. However, as the excess among butchers and some workers in health occupations was consistent with previous reports, more indepth research is warranted to address the hypothesis.

Independent expression of serological markers of thyroid autoimmunity and hepatitis virus C infection in the general population: results of a community-based study in north-western Sardinia.

To assess the relationship between serological markers of thyroid autoimmunity and chronic hepatitis C, we surveyed the general population of two villages in the region of Sardinia, Italy, where infection with hepatitis viruses is endemic and the prevalence of autoimmune diseases is elevated. A total of 1310 subjects aged 6-88 years (65% of the total resident population) participated in the survey, and 1233 (94%; 444 males and 789 females) agreed to provide a blood sample. Autoantibodies to thyroid peroxidase (anti-TPO) were measured by radioimmunoassay; antibodies to HCV (anti-HCV) by a third generation enzyme immunoassay and borderline positive results confirmed by recombinant immunoblot assay. For both anti-HCV and anti-TPO the age- and gender-standardized prevalence rates (SPR) were calculated and the significance of the association between the two antibodies tested by Yates corrected chi2 test. The overall SPR for anti-HCV was 50.7x10(-3) (86/1,233), similar between men [49.1x10(-3) (22/444)] and women [52.3x10(-3) (64/789)]. The overall SPR for anti-TPO was 136.9x10(-3) (204/1,233), and that among women [201x10(-3) (174/789)] was almost 3-fold that among men [71.6x10(-3) (30/444)]. A concurrent anti-HCV and anti-TPO positivity was found in a small minority of subjects [8/1,233 (0.65%)], all women aged 57-81 years. The SPR for the two concurrent events was 3.3x10(-3), which was not significantly different (Yates corrected chi2 test = 0.65) from that expected under the assumption of unrelated events. To explore whether HCV infection is a risk factor for anti-TPO positivity, we designed a case-control study with anti-TPO positive subjects as the cases, and anti-TPO negative subjects as the controls. The age- and gender-adjusted odd ratio (OR) was 0.4 (95% CI 0.2,0.7), indicating a negative association. In conclusion, no evidence for epidemiological association of circulating thyroid autoantibodies and antibodies to HCV was found. Our findings do not therefore support a pathogenetic link between HCV infection and thyroid autoimmunity.

Mortality of Sardinian lead and zinc miners: 1960-88.

The mortality of 4740 male workers of two lead and zinc mines was followed up from 1960 to 1988. Exposure to respirable dust was comparable in the two mines, but the median concentration of silica in respirable dust was 10-fold higher in mine B (12.8%) than in mine A (1.2%), but the mean annual exposure to radon daughters in underground workplaces differed in the opposite direction (mine A: 0.13 working levels (WL), mine B: 0.011 WL). Total observed deaths (1205) were similar to expected figures (1156.3) over a total of 119 390.5 person-years at risk. Underground workers of mine B had significant increases in risk of pulmonary tuberculosis (SMR 706, 95% confidence interval (95% CI) 473-1014) and non-malignant respiratory diseases (SMR 518; 95% CI 440-1606), whereas the only significant excess at mine A was for non-malignant respiratory diseases (SMR 246; 95% CI 191-312). Total cancer and lung cancer mortality did not exceed the expectation in the two mines combined. A 15% excess mortality for lung cancer, increased up to an SMR 204 (95% CI 89-470) for subjects employed > or = 26 years, was, however, found among underground workers in mine A who on the average experienced an exposure to radon daughters 10-fold higher than those of mine B. By contrast, despite their higher exposure to silica, mine B underground workers experienced a lower than expected lung cancer mortality. A ninefold increase in risk of peritoneal and retroperitoneal cancer combined was also found among underground workers of mine A (SMR 917; 95% CI 250-2347; based on four deaths). A causal association with workplace exposures is unlikely, however, as the SMR showed an inverse trend by duration of employment. These findings are consistent with low level exposure to radon daughters as a risk factor for lung cancer among metal miners. Exposure to silica at the levels estimated for the mine B underground environment did not increase the risk of lung cancer.

Lung cancer mortality among female mine workers exposed to silica.

A mortality cohort study (1951-1988) was conducted on 526 female workers in two lead and zinc mines in southwestern Sardinia (Italy), 310 of whom had been exposed to silica. Women exposed to silica showed a nonsignificant 38% increase in the standardized mortality ratio (SMR) for nonmalignant respiratory diseases, which was highest and statistically significant among women at the mine with the highest exposure to silica (SMR = 217; 95% confidence interval [CI] = 104, 400; based on 10 observed and 4.6 expected deaths). Five deaths from lung cancer also occurred among those exposed to silica (SMR = 283; 95% CI = 91,660), but the excess was not related to the level or duration of exposure. No information was available concerning lifestyle risk factors in this cohort. However, smoking was quite rare among Sardinian women at the time cohort members worked, so it may be presumed that very few of them were smokers.

[Mortality in workers of a primary aluminum foundry in Portovesme in Sardinia]. / Mortalità nei lavoratori della fonderia di alluminio primario di Portovesme in Sardegna.

The standard mortality rates (SMRs) were calculated for 1148 workers of a primary aluminium plant in Portovesme, Sardinia, hired between 1971, when production started, and 1980. Status (living or decreased) was ascertained as at 31 December 1990 and the relationship between observed and expected deaths with respective 95% confidence limits were calculated on the basis of age-specific regional rates for each calendar year of the follow-up. The SMR for all causes was 81 with confidence limits between 61 and 108 based on a total of 48 deaths. Mortality due to malignant neoplasms did not differ from the expected rate. The observed deaths due to lung cancer were decidedly less than the expected number (3 observed versus 4.7 expected). A significant excess of cancer of the pancreas was observed with special reference to anode production, based, however, on only 3 observed cases against 0.8 expected. In the absence of a more precise definition of the causes of death, of the environmental exposure levels and of the non-occupational confounding factors, and considering the young age of the cohort under study, it is at present doubtful whether the excess of cancer of the pancreas can be associated with work in the primary aluminium industry. The results should therefore be taken as preliminary, indicating that further studies are required.

Occupational exposure to lead and blood cholesterol in glucose-6-phosphate dehydrogenase deficient and normal subjects.

The effect of chronic lead poisoning on blood cholesterol levels of 148 patients, admitted to the Institute of Occupational Medicine of the University of Cagliari (Italy), was studied in connection with the genetic pattern of Glucose-6-Phosphate Dehydrogenase (G6PD) activity. The erythrocyte G6PD activity of twenty-six patients was genetically deficient. Multiple regressions were elaborated including the following in the model as independent variables: age, Quetelet index and blood lead or urinary lead in the 24 hours following 15 mg/Kg of i.v. calcium ethylen-diamine-tetracetate (EDTA) (PbUEDTA), expressed as a ratio with body weight (PbUEDTA/Kg). Dependent variables were alternatively, total cholesterol, cholesterol esters, LDL and HDL cholesterol. The analysis showed that G6PD deficient subjects have generally lower intercepts, but only for HDL the difference approached the statistical significance. Lead poisoning affected blood cholesterol of G6PD deficient subjects differently from normal ones: while total cholesterol and LDL tended to decrease in both, positive slopes were observed for cholesterol esters in G6PD deficient and for HDL in G6PD normal subjects.

Mortality from lung cancer among Sardinian patients with silicosis.

The mortality of 724 subjects with silicosis, first diagnosed in 1964-70 in the Sardinia region of Italy, was followed up through to 31 December 1987. Smoking, occupational history, chest x ray films, and data on lung function were available from clinical records for each member of the cohort. The overall cohort accounted for 10,956.5 person-years. The standardised mortality ratios (SMRs) for selected causes of death (International Classification of Diseases (ICD) eighth revision) were based on the age specific regional death rates for each calendar year. An excess of deaths for all causes (SMR = 1.40) was found, mainly due to chronic obstructive lung disease, silicosis, and tuberculosis with an upward trend of the SMR with increasing severity of the International Labour Office (ILO) radiological categories. Twenty two subjects died from lung cancer (SMR = 1.29, 95% confidence interval (95% CI) = 0.8-2.0). The risk increased after a 10 and 15 year latency but the SMR never reached statistical significance. No correlation was found between lung cancer and severity of the radiological category, the type of silica (coal or metalliferous mines, quarries etc), or the degree of exposure to silica dust. A significant excess of deaths from lung cancer was found among heavy smokers (SMR = 4.11) and subjects with airflow obstruction (SMR = 2.83). A nested case-control study was planned to investigate whether the association between lung cancer and airway obstruction was due to confounding by smoking. No association was found with the ILO categories of silicosis or the estimated cumulative exposure to silica. The risk estimate for lung cancer by airflow obstruction after adjusting by cigarette consumption was 2.86 for a mild impairment and 7.23 for a severe obstruction. The results do not show any clear association between exposure to silica, severity of silicosis, and mortality from lung cancer. Other environmental or individual factors may act as confounders in the association between silicosis and lung cancer. Among them, attention should be given to chronic airways obstruction as an independent risk factor for lung cancer in patients with silicosis.

Nitrate and nitrite exposure in Italian populations with different gastric cancer rates.

Exposure to nitrate and nitrite from dietary sources was estimated by questionnaire and measurement of salivary levels of the ions in residents of four regions of Italy with longstanding, contrasting, gastric cancer mortality rates. Whether using salivary levels or dietary questionnaire estimations no association was found between nitrate and nitrite exposure and gastric cancer mortality rates. For salivary nitrate and nitrite, the intra-provincial variation was greater than any inter-province difference. However, for dietary nitrate and nitrite intakes, there were significant differences between the regional groups (but not related to gastric cancer risk). Despite the limitations of the methods used, there was a weak positive association between salivary concentrations of nitrate and questionnaire assessment. Dietary factors are likely to play key roles at different stages of the gastric carcinogenic process. Nitrate may play a part but is unlikely to be a rate-limiting factor in all individuals or populations.