A Molecular Epidemiology Project on Diet and Cancer: The Epic-Italy Prospective Study. Design and Baseline Characteristics of Participants

Environmental ozone exposure and oxidative DNA damage in adult residents of Florence, Italy

In 71 adults residing in Florence, Italy, enrolled in a prospective study, we investigated the correlation between individual levels of oxidative DNA damage detected by the Comet assay in circulating lymphocytes, and a specific ozone exposure score calculated in 10 different time-windows (0-5 to 0-90 days) before blood drawing, based on daily measurements provided by the local environmental monitoring system. Overall, statistically significant positive correlations between average ozone concentrations and DNA damage emerged in almost all time-windows considered; correlations were more evident among males, non-smokers, and traffic-exposed workers. Multivariate regression analyses taking into account selected individual characteristics, showed an independent effect on DNA damage of average ozone concentrations in the last 60-90 days before blood drawing. Local residents showed a divergent pattern with correlations restricted to shorter time-windows. Our results suggest that ozone concentrations at ground levels modulate oxidative DNA damage in circulating lymphocytes of residents of polluted areas.

DNA adducts and PM(10) exposure in traffic-exposed workers and urban residents from the EPIC-Florence City study

Air pollution and particulate matter in urban areas have been associated with increased mortality from cardiovascular and respiratory diseases and increased cancer risk. Carcinogenic effects of particulate matter have been related to the contents of specific compounds, such as polycyclic aromatic hydrocarbons. The latter may form bulky DNA adducts, that may be considered as candidate markers of cancer risk. We have recently shown that traffic-exposed workers and the general population in Florence have divergent levels of DNA adducts, possibly related to different levels of exposure to genotoxic agents from vehicle emissions. In the current study, in a series of 214 Florence City healthy adults enrolled in a prospective study in the period 1993-1998 (152 residents / 62 traffic-exposed workers), we investigated the correlation between individual levels of DNA bulky adducts and PM(10) exposure scores based on daily environmental measures provided by the local Environmental Protection Agency for the whole study period, by two types of urban monitoring stations (high- and low-traffic). We found that PM(10) cumulative scores from high-traffic stations over the last 1-2 weeks prior to blood drawing significantly correlated (r=0.58, p=0.02) with DNA adduct levels among non-smoking traffic-exposed workers (but not among residents with no occupational exposure to vehicle emissions). A multivariate regression analysis adjusted for possible confounders confirmed these findings. PM(10) scores from low-traffic stations did not show any correlation. These results show that DNA adduct levels in non-smoking workers reflect the average levels of exposure to PM(10) in high-traffic urban areas experienced over a time period of 1-2 weeks. Since DNA adduct levels have been found predictive of lung cancer risk, our findings provide clues relevant to the reduction of genotoxic damage and possibly cancer risk among traffic-exposed urban workers.

A dietary pattern rich in olive oil and raw vegetables is associated with lower mortality in Italian elderly subjects

Dietary habits play an important role in healthy ageing. We have investigated the role of dietary patterns on overall mortality in a large series of Italian elderly, recruited in five EPIC cohorts in Northern (Varese and Turin), Central (Florence) and Southern Italy (Naples and Ragusa).A total of 5611 subjects (72·6 % women) aged 60 years or older, enrolled in 1993–1998, were prospectively followed (median 6·2 years), with 152 deaths (98 women). Four major dietary patterns were identified by using an exploratory factor analysis based on dietary information collected at enrolment. The associations between these dietary patterns and overall mortality were evaluated by Cox models adjusted for potential confounders. The ‘Olive Oil & Salad’ pattern, characterised by a high consumption of olive oil, raw vegetables, soups and poultry, emerged as being inversely associated with overall mortality in both crude and adjusted models. After adjustment for gender, age and caloric intake, overall mortality was reduced by approximately 50 % in the highest quartile and a significant trend emerged (P = 0·008). This association persisted after adjusting for several additional confounders (hazard ratio (HR) 0·50; 95 % CI 0·29, 0·86; P for trend =  0·02). An association of the ‘Pasta & Meat’ pattern (characterised by pasta, tomato sauce, red meat, processed meat, added animal fat, white bread and wine) with increased overall mortality was also suggested, but only for the highest quartile in a multivariate model. Dietary recommendations aimed at the Italian elderly population should support a dietary pattern characterised by a high consumption of olive oil, raw vegetables and poultry.

Feasibility of Running Clinics to Collect Biological Specimens in a Nationwide Cohort Study—Adventist Health Study-2

PURPOSE

Collecting biologic and questionnaire data allows analyses that can include both genetic/biomarker and behavioral factors. Therefore, the feasibility of collecting biological specimens from a nationally dispersed cohort (Adventist Health Study-2) was tested.

METHODS

We selected 2130 subjects from California, Washington, Texas, and Louisiana to simulate a widely scattered cohort. Clinics were held at local church halls. Nonclinic attendees were invited to mail in their blood samples. The remaining nonparticipants were offered a home visit by a venipuncturist.

RESULTS

Sixty-four percent of nonblack and 38.4% of black invitees attended the clinics. Another 11.3% of nonblack and 5.9% of black subjects from a subsample mailed in their blood samples. A venipuncturist visit collected samples from another 5.3% of nonblack subjects, but hurricanes disrupted this method among blacks. This experience suggests that we could collect biological samples from 81.2% and at least 44.3% of the nonblack and black subjects, respectively.

CONCLUSIONS

We have demonstrated the feasibility of collecting biological specimens from black as well as nonblack subjects, with an efficient, cost-effective system, and limited personpower, overcoming many of the complexities imposed by scattered subjects, diversity of culture, as well as cumbersome and varied state legislation governing clinics and clinic personnel.

Trends in incidence rates of oesophagus and gastric cancer in Italy by subsite and histology, 1986-1997

OBJECTIVE

Population-based studies in Western countries suggest that the incidence of oesophageal adenocarcinoma (OA) and gastric cardia adenocarcinoma (GCA) is increasing, whereas the incidence of distal gastric carcinoma and oesophageal squamous cell carcinoma (OSCC) is declining. This is the first population-based study carried out in a southern European region to evaluate the time trends in incidence rates of oesophageal and gastric tumours according to subsite and histology over the period 1986-1997.

METHODS

Cancer cases were drawn from seven registries of the Italian Network of Cancer Registries, which covers approximately 9% of the Italian population (annual average 5 027 944). Time trends in age and sex-standardized incidence rates were reported. Estimated annual percentage changes (EAPC) and related 95% confidence intervals (CI) were estimated by modelling age, sex, subsite and morphology-specific incidence rates through Poisson log-linear regression, and whenever necessary negative-binomial regression. Overall, 25 895 gastric and 2497 oesophageal carcinomas were examined.

RESULTS

On the whole, an increasing trend was observed for OA plus GCA. The increase was statistically significant in younger women (<60 years: EAPC 3.7; 95% CI 0.2; 7.3) and in older men (>75 years: EAPC 4.0; 95% CI 1.2; 6.9). Similar trends were also observed in proximal gastric cancer (GCA plus fundus). A decline in the stomach subfundus incidence was observed in both sexes and in each age group. OSCC decreased significantly in men (EAPC-2.6; 95% CI-4.1;-0.9).

CONCLUSIONS

It is plausible that the different tendencies in oesophageal and proximal gastric cancer in men and women are attributable to heterogeneous distributions of risk factors by sex or age.

Dietary and lifestyle determinants of mammographic breast density. A longitudinal study in a Mediterranean population

High mammographic breast density (H-MBD) has been associated with increased breast cancer (BC) risk, even after adjustment for established BC risk factors. Only a few studies have examined the influence of diet on MBD. In a longitudinal study in Florence, Italy, we identified about 2,000 women with a mammogram taken 5 years after enrollment, when detailed information on dietary and lifestyle habits and anthropometric measurements had been collected. Original mammograms have been identified and retrieved (1,668; 83%), and MBD was assessed by 2 experienced readers, according to Wolfe's classification and a semiquantitative scale. By logistic analysis, we compared women with H-MBD (P2 + DY according to Wolfe's classification) with those with low-MBD (N1 + P1). H-MBD was confirmed to be inversely associated with BMI, number of children and breast feeding, while it was directly associated with higher educational level, premenopausal status and a previous breast biopsy. In multivariate analyses adjusted for non-dietary variables, H-MBD was inversely associated with increasing consumption of vegetables (p for trend = 0.005) and olive oil (p for trend = 0.04). An inverse association was also evident between H-MBD and frequent consumption of cheese and high intakes of beta-carotene, vitamin C, calcium and potassium (p for trend < or = 0.05). On the other hand, we found a positive association with increasing consumption of wine (p for trend = 0.01). This large longitudinal study, the first carried out in Mediterranean women, suggests that specific dietary components may play a key role in determining MBD in this population, thus possibly modulating BC risk.

Associations between dietary pattern and lifestyle, anthropometry and other health indicators in the elderly participants of the EPIC-Italy cohort

INTRODUCTION

Epidemiological studies have shown that dietary behaviour is an important aetiological factor in various chronic diseases. We used principal component factor analysis to identify dietary patterns and to examine the associations of these patterns with health-related variables in a sample of elderly (> or =60 years) Italians participating in the European Prospective Investigation into Cancer and Nutrition (EPIC).

METHODS AND RESULTS

Exploratory factor analysis was applied to the intake of food groups as estimated by semi-quantitative food questionnaires. Individual participants were assigned factor scores, indicating the extent to which their diet conformed to each of the four dietary patterns identified: prudent (cooked vegetables, pulses, cabbage, seed oil and fish); pasta & meat (pasta, tomato sauce, red meat, processed meat, bread and wine); olive oil & salad (raw vegetables, olive oil, soup and chicken); and sweet & dairy (sugar, cakes, ice cream, coffee and dairy). Highly educated people had high scores on prudent and low scores on pasta & meat. The pasta & meat and prudent patterns were strongly positively associated with body mass index (BMI) and waist-to-hip ratio (WHR) in men and women. Hyperlipidaemic men and women consumed more of the prudent and olive oil & salad patterns and less of the sweet & dairy pattern than those with normal lipids. The olive oil & salad was significantly higher and the pasta & meat and sweet & dairy patterns significantly lower in men and women who had dieted over the previous year, suggesting awareness of the health consequences of these patterns.

CONCLUSIONS

Dietary pattern analysis provides a characterization of recurrent dietary behaviour in elderly people, and can be used to provide tangible dietary advice to elderly people.

Twenty-four-hour urinary excretion of ten pesticide metabolites in healthy adults in two different areas of Italy (Florence and Ragusa)

The determination of pesticide metabolites in human biological fluids represents an important biomarker of exposure in the general population and exposed workers. In the frame of a prospective study, we measured the 24-h urinary excretion of 10 pesticide metabolites to evaluate non-occupational exposure to pesticides in the general population in two different areas in Italy. We collected 24-h urine samples from 69 healthy adults residing in Florence (Central Italy, n = 51) and Ragusa (Southern Italy, n = 18). The volunteers (25 males, 44 females; mean age 56 years) did not report any occupational exposure. We measured: six alkylphosphates, aspecific metabolites of organophosphorus pesticides [dimethylphosfate (DMP), dimethylthiophosfate (DMTP), dimethyldithiophosfate (DMDTP), diethylphosfate (DEP), diethylthiophosfate (DEDP), and diethyldithiophosfate (DEDTP)]; 3,5,6-trichloro-2-pyridinol (TCP), the main metabolite of chlorpyrifos; 3-phenoxybenzoic acid (3-PBA), a metabolite of pyrethroid insecticides; ethylenethiourea (ETU) a metabolite of ethylenebisdithiocarbamates; methamidophos (METH), an organophosphorus insecticide. We also measured PABA excretion as compliance marker (mean recovery 95%). Dimethylphosphates were found in detectable concentrations in the majority of samples (89.9%, 82.6% and 60.9% for DMP, DMTP and DMDTP, respectively). Urinary diethylphosphates (DEP, DETP, DEDTP) concentrations were above the detection limit in 80.9%, 61.8% and 27.5% of samples, respectively. TCP, 3-PBA and ETU were detected in 78.3%, 53.6% and 21.7% of samples, respectively. Methamidophos was detected in two samples (2.8%). The median number of metabolites detected in the same urine sample was 6 (range 0-9). Excretion levels were highest for alkylphosphates, particularly for DMTP (median: 142.6 nmol/day). Multivariate analysis showed statistically significant differences between these two groups of adults, with higher mean values of urinary excretion of alkylphosphates, TCP and ETU in Florence in comparison to Ragusa. Overall, a very high percentage of 24-h urine samples positive for several pesticide metabolites emerged, with higher levels of urinary daily excretion in subjects residing in the more urbanised area. Our results suggest that food monitoring programs should be supported by general campaigns aimed to reduce the use of pesticides in agriculture.

DNA bulky adducts in a Mediterranean population correlate with environmental ozone concentration, an indicator of photochemical smog

Ozone (O(3)), the major oxidant component in photochemical smog, mostly derives from photolysis of nitrogen dioxide. O(3) may have biologic effects directly and/or via free radicals reacting with other primary pollutants and has been reported to influence daily mortality and to increase lung cancer risk. Although DNA damage may be caused by ozone itself, only other photochemical reaction products (as oxidised polycyclic aromatic hydrocarbons) may form bulky DNA adducts, a reliable biomarker of genotoxic damage and cancer risk, showing a seasonal trend. In a large series consisting of 320 residents in the metropolitan area of Florence, Italy, enrolled in a prospective study for the period 1993-1998 (206 randomly sampled volunteers, 114 traffic-exposed workers), we investigated the correlation between individual levels of DNA bulky adducts and a cumulative O(3) exposure score. The average O(3) concentrations were calculated for different time windows (0-5 to 0-90 days) prior to blood drawing for each participant, based on daily measurements provided by the local monitoring system. Significant correlations between DNA adduct levels and O3 cumulative exposure scores in the last 2-8 weeks before enrollment emerged in never smokers. Correlations were highest in the subgroup of never smokers residing in the urban area and not occupationally exposed to vehicle traffic pollution, with peak values for average concentrations 4-6 weeks before enrollment (r = 0.34). Our current findings indicate that DNA adduct formation may be modulated by individual characteristics and by the cumulative exposure to environmental levels of ozone in the last 4-6 weeks, possibly through ozone-associated reactive pollutants.