The relationship between ambient particulate matter and respiratory mortality: a multi-city study in Italy.

The association of air pollutants with natural and respiratory mortality has been consistently reported. However, several aspects of the relationship between particulate matter with a 50% cut-off aerodynamic diameter of 10 µm (PM(10)) and respiratory mortality require further investigation. The aim of the present study was to assess the PM(10)-respiratory mortality association in Italy and examine potentially susceptible groups. All deaths from natural (n=276,205) and respiratory (n=19,629) causes among subjects aged ≥ 35 yrs in 10 northern, central and southern Italian cities in 2001-2005 were included in the study. Pollution data for PM(10), nitrogen dioxide and ozone were also obtained. A time-stratified case-crossover analysis was carried out. Different cumulative lags were selected to analyse immediate, delayed, prolonged and best-time effects of air pollution. The shape of the exposure-response curve was analysed. Age, sex, chronic conditions and death site were investigated as potential effect modifiers. We found a 2.29% (95% CI 1.03-3.58%) increase in respiratory mortality at 0-3 days lag. The increase in respiratory mortality was higher in summer (7.57%). The exposure-response curve had a linear shape without any threshold. Sex and chronic diseases modified the relationship between particular matter (PM) and respiratory mortality. The effect of PM on respiratory mortality was stronger and more persistent than that on natural mortality. Females and chronic disease sufferers were more likely to die of a respiratory disease caused by air pollution than males and healthy people.

Profiling hospital performance to monitor the quality of care: the case of COPD.

Comparative outcomes data are widely used to monitor quality of care in the cardiovascular area; little is available in the respiratory field. We applied validated methods to compare hospital outcomes for chronic obstructive pulmonary disease (COPD) exacerbation. From the hospital information system, we selected all hospital admissions for COPD exacerbation in Rome (for 2001-2005). Vital status within 30 days was obtained from the municipality mortality register. Each hospital was compared to a pool of hospitals with the lowest adjusted mortality rate (the benchmark). Age, sex and several potential clinical predictors were covariates in logistic regression analysis. 12,756 exacerbated COPD patients were analysed (mean age 74 yrs, 71% males). Diabetes, hypertension, ischaemic heart disease, heart failure and arrhythmia were the most common coexisting conditions. The average crude mortality in the benchmark group was 3.8%; in the remaining population it was 7.5% (range 5.2-17.2%). In comparison with the benchmark, the relative risk of 30-day mortality varied widely across the hospitals (range 1.5-5.9%). A large variability in 30-day mortality after COPD exacerbation exists even considering patients' characteristics. Although these results do not detect mechanisms related to worse outcomes, they may be useful to stimulate providers to revision and improvement of COPD care management.

The impact on risk-factor analysis of different mortality outcomes in COPD patients.

The aim of the present study was to analyse the role of potential selection processes and their impact when evaluating risk factors for 30-day mortality among patients hospitalised for chronic obstructive pulmonary disease (COPD). A cohort of 26,039 patients aged > or = 35 yrs and hospitalised with COPD were enrolled. A 30-day follow-up was carried out using both the cause mortality register (CMR) and the hospital discharge register (HDR). Individual and hospital factors associated with 30-day mortality were studied using both mortality outcomes. The 30-day mortality rate was 1.21.1,000 patient-days(-1) (95% confidence interval (CI) 1.14-1.29) using the CMR, and 1.06.1,000 patient-days(-1) (95% CI 0.98-1.13) using the HDR. Male patients, the most poorly educated, those who resided outside Rome and those who had more than one hospitalisation in the previous 2 yrs were more likely to die after discharge than when hospitalised. The most frequent cause of in-hospital death was respiratory disease and after discharge, heart disease. Older age, male sex, comorbidities, previous hospitalisations for respiratory failure, and admission to a ward not appropriate to treat respiratory diseases were the most important predictors of 30-day mortality. Using in-hospital 30-day mortality provides a significantly different estimate of the role of specific risk factors.

The concurrent COPD mortality doubles the mortality estimate from COPD as underlying cause in Lazio, Italy.

BACKGROUND: In Lazio region (Italy), mortality data are currently available from the death cause registry (DCR), which reports only underlying causes. Mortality due to other causes, defined concurrent mortality, are need to appropriately estimate the health impact from chronic diseases. The aims of the study were to estimate concurrent mortality from chronic obstructive pulmonary disease (COPD), using hospital discharge registry (HDR), to discuss the validity and limits of this method, and to compare underlying and concurrent mortality from COPD in the Lazio region. METHODS: A mortality study was carried out for residents who died in 1996-2000 with COPD listed as the underlying cause of death and those who died in the hospital with a different underlying cause of death listed but with a discharge diagnosis of COPD. Age-standardized mortality rates were obtained for males and females separately, using the direct method. A random sample of death certificates was used to validate concurrent causes of death as defined from discharge diagnoses. RESULTS: Age-standardised mortality for COPD as underlying cause of death was 3.68/10,000 in male and 2.29/10,000 in female residents. Mortality increased slightly in the study period for women, but no trend was evident. Age-standardised mortality for COPD as concurrent cause of death was 2.39/10,000 in male and 1.31/10,000 in female residents. The positive predictive value for concurrent COPD mortality was 54.3%. CONCLUSIONS: Concurrent COPD mortality contributed 62.3% to the whole mortality. The estimates of concurrent COPD mortality were comparable to those reported in other countries, though using hospital data may overestimate the real concurrent mortality as estimated from death certificates.

The burden of hospitalised pneumonia in Lazio, Italy, 1997-1999.

OBJECTIVE: To evaluate the burden of hospitalised pneumonia in adults in the Lazio region (1997-1999); to describe community-acquired pneumonia (CAP), suspected nosocomial infection (NI) and AIDS-related pneumonia. METHODS: Using data from the Hospital Information System, we traced the hospitalisation history of patients and classified CAP, NI and AIDS-related pneumonia. RESULTS: During the study period, 30517 incident events of pneumonia occurred: 20497 CAP, 9760 NI, and 964 AIDS-related pneumonia; 704 of these were also NI (annual incidence rate 158, 75 and 7.4 per 100 000 population, respectively). The mean ages were 65, 69 and 38 years for CAP, NI, and AIDS-related pneumonia, respectively. Higher hospitalisation rates were observed in Rome than in the rest of the region for NI and AIDS-related cases, but not for CAP. Lower socioeconomic groups showed a higher incidence of CAP and AIDS-related pneumonia. Peaks of incidence were observed in winter for CAP and NI. Only 20% of pneumonias have an aetiological diagnosis. In-hospital fatality rates were 9.4%, 29.3% and 11.2% for CAP, NI and AIDS-related pneumonia, respectively. CONCLUSION: The high incidence and fatality of CAP and NI, especially among the elderly, makes these diseases a problem that is re-emerging in industrialised countries with an ageing population.

Cancer among farmers in central Italy.

This case-referent study evaluated cancer risks among farmers in central Italy. Cancer cases (N = 1674, 17 sites) were selected from all deceased men aged 35-80 years; a random sample of 480 decedents formed the reference series. Farmers had a decreased risk of lung and bladder cancer and melanoma and nonsignificant excess risks for stomach, rectal, kidney, and nonmelanoma skin cancer. Stomach and kidney cancer were significantly increased among the farmers with > 10 years' experience, and stomach, rectal, and pancreatic cancer were increased among licensed pesticide users with > 10 years' experience. Possible relationships emerged between specific crops and cancer: fruit and colon and bladder cancer, wheat and prostate cancer, olives and kidney cancer, and potato and kidney cancer. The results regarding stomach, pancreatic, lung, bladder, and prostate cancer and melanoma congrue with earlier results. The kidney cancer excess, the association of colon and bladder cancer with orchard farming, and the excess of rectal cancer among licensed farmers are new and unexpected findings.

Infectious diseases in Rome during the Millennium Year.

During 2000, the millennium year, 26 million people visited Rome. An improved surveillance system for infectious diseases, especially for foodborne disease outbreaks (FBDO), meningitis, and legionnaires' disease was introduced in 1997. This rapid alert network links public health services with the principal sources of diagnosis and laboratory based surveillance. For travel related legionnaires' disease, international surveillance was implemented. Specific control measures for FBDOs were adopted. No increase in the overall incidence of these diseases was observed, and no atypical pathogens in FBDOs or meningitis were isolated in 2000 relating to 1998-99. Cases of legionnaires' disease and FBDOs involving foreign tourists increased (10/4 and 7/2 observed/expected respectively). Three out of six FBDOs involving pilgrims occurred in religious guesthouses. While an increase in cases of legionnaires' disease and FBDOs among foreign tourists was observed by the surveillance system, the millennium year did not influence the epidemiology of infectious diseases in the residential population of Lazio.

Cohort study of mortality among farmers and agricultural workers.

A cohort study was made of the mortality experience of 1701 male and 426 female farm workers (Aprilia, Italy) during the period 1972-1988. A low overall mortality was found due mainly to a decreased risk of circulatory diseases and respiratory conditions. Also, the overall cancer mortality was reduced (SMR = 0.88 for males and 0.58 for females). No statistically significant excesses were observed in cancer mortality, but there was an evident tendency towards an increased risk of gastric cancer (0 = 23, SMR = 1.24), renal cancer (0 = 5, SMR = 2.12), skin cancer (0 = 2, SMR = 1.67) and leukemia (0 = 6, SMR = 1.54), mainly of the myeloid type. Finally, 41 lung cancer cases were observed against 40.12 expected. Under 65 years excess deaths were found for all cancer sites investigated except cancer of the lymphatic and hemopoietic tissues. Since farmers usually have a low lung cancer rate, the increased mortality in the young age group (0 = 24, SMR = 1.28) and also the excess of kidney cancer (0 = 4, SMR = 3.67), although not statistically significant, deserve consideration in relation to past exposure to pesticides, especially DDT, in this population.

[The monitoring of cholinesterases in farm workers and tradesmen exposed to phosphoric esters and carbamates]. / Monitoraggio delle colinesterasi in lavoratori agricoli e commercianti esposti ad esteri fosforici e carbammati.

Cholinesterase (ChE) levels (Ellman method) were monitored in 90 subjects (69 males and 21 females) exposed to carbamate and organophosphate pesticides (78 agricultural workers and 12 pesticide vendors). Pre-exposure baseline values of plasma and red blood cell cholinesterase activities were defined for each subject with two blood samples (23 workers) or three blood samples (59 workers) taken almost thirty days after the last exposure. After control of intra-individual variation, 8 subjects with only one pre-exposure value and 13 with a coefficient of variation above 30% were excluded. For the other 59 subjects, the intra-individual variation of erythrocyte ChE (16%) was similar to the inter-individual one (15%), whereas the inter-individual variation of plasma ChE (21%) was higher than the intra-individual one (14%). Laboratory variation for plasma ChE measurements was 8%. Baseline values were analyzed (ANOVA) for sex, age, task and hour and season of sampling. Both erythrocyte and plasma enzymes, corrected for hematocrit, were lower in females. Plasma cholinesterase activity was lower in "re-entry" agricultural workers and in pesticide vendors. Post-exposure cholinesterase activity was measured in 54 workers within a few (1-21) days after last handling. Average relative reduction was 15.2% (95% C.I. = 4.9%-25.5%) in erythrocyte cholinesterase activity and 29.1% (95% C.I. = 18.2%-40.1%) in plasma cholinesterase activity. The one-way variance analysis showed marked plasma ChE reduction in mixers, loaders and appliers (36%, 95% C.I. = 24%-48%) and in parathion handlers (35%, 95% C.I. = 21%-49%. No significant reduction in blood cell cholinesterase activity in relation to task and to pesticide handled was observed. We conclude that the intra-individual variations of the baseline values were higher for three repetitions (88% and 84% of the population were within a variability of less than 30%, for AChE and for ChE respectively) than for two repetitions (91% and 88% of the population were within 30% of variability for AChE and for ChE respectively). The figures show a greater sensitivity of plasma ChE activity in acute exposure, probably due to a poor reliability in detection of erythrocyte ChE by local laboratories. The maximum reduction (38%, 95% C.I. = 22%-53%) in plasma ChE activity was observed within six days of the last exposure in loaders and appliers.

Risk factors for multidrug resistant tuberculosis in Europe: a systematic review.

BACKGROUND: The resurgence of tuberculosis (TB) in western countries has been attributed to the HIV epidemic, immigration, and drug resistance. Multidrug resistant tuberculosis (MDR-TB) is caused by the transmission of multidrug resistant Mycobacterium tuberculosis strains in new cases, or by the selection of single drug resistant strains induced by previous treatment. The aim of this report is to determine risk factors for MDR-TB in Europe. METHODS: A systematic review was conducted of published reports of risk factors associated with MDR-TB in Europe. Meta-analysis, meta-regression, and sub-grouping were used to pool risk estimates of MDR-TB and to analyse associations with age, sex, immigrant status, HIV status, occurrence year, study design, and area of Europe. RESULTS: Twenty nine papers were eligible for the review from 123 identified in the search. The pooled risk of MDR-TB was 10.23 times higher in previously treated than in never treated cases, with wide heterogeneity between studies. Study design and geographical area were associated with MDR-TB risk estimates in previously treated patients; the risk estimates were higher in cohort studies carried out in western Europe (RR 12.63; 95% CI 8.20 to 19.45) than in eastern Europe (RR 8.53; 95% CI 6.57 to 11.06). National estimates were possible for six countries. MDR-TB cases were more likely to be foreign born (odds ratio (OR) 2.46; 95% CI 1.86 to 3.24), younger than 65 years (OR 2.53; 95% CI 1.74 to 4.83), male (OR 1.38; 95% CI 1.16 to 1.65), and HIV positive (OR 3.52; 95% CI 2.48 to 5.01). CONCLUSIONS: Previous treatment was the strongest determinant of MDR-TB in Europe. Detailed study of the reasons for inadequate treatment could improve control strategies. The risk of MDR-TB in foreign born people needs to be re-evaluated, taking into account any previous treatment.

The impact of the Catholic Jubilee in 2000 on infectious diseases. A case-control study of giardiasis, Rome, Italy 2000-2001.

Mass gatherings are believed to increase the transmission of infectious diseases although surveillance systems have shown a low impact. The Catholic Jubilee was held in Rome, Italy in 2000. We conducted a case-control study to analyse the risk factors of giardiasis among residents. All diseases reported to the laboratory surveillance system from January 2000 to May 2001 were compared with hospital controls concurrently selected in the same season as cases and frequency-matched for age and birth country. Fifty-two cases (44.1%) and 72 controls were enrolled. In the multivariable analysis factors associated with giardiasis among adults were: travelling abroad (OR 24.2, P>0.01), exposure to surface water (OR 4.80, P=0.05), high educational level (OR 3.8, P=0.03). Having a maid from a high-prevalence country was independently associated (OR 2.3) although not statistically significant. This is the only exposure that changed during the Jubilee.

Tuberculosis treatment outcomes in Europe: a systematic review.

In order to facilitate the control of tuberculosis (TB), the World Health Organization (WHO) has defined a standardised short-course chemotherapy and a strategy, directly observed therapy. In 2000, WHO surveillance of TB treatments in Europe recorded a successful outcome rate of 77%. The aim of this report is to estimate treatment outcomes in European countries based on published studies and to identify their determinants. A systematic review was conducted of published reports of TB treatment outcomes in Europe. Meta-analysis, meta-regression and subgrouping were used to pool treatment outcomes and analyse associations with mean age, sex, immigration status and multidrug resistance. Of the 197 articles identified in the search, 26 were eligible for the review; 74.4% of outcomes were successful, 12.3% were unsuccessful and 6.8% of patients died. Heterogeneity was high for all outcomes. National estimates were possible for six countries. Multidrug resistance was inversely associated with successful outcome, which were fewer in populations with >9% multidrug-resistant TB, and in patients aged <44 yrs. Successful tuberculosis treatment outcomes were below the 85% threshold suggested by the World Health Organization. There was an inverse association with levels of multidrug-resistant tuberculosis. The unexplained heterogeneity between the studies for unsuccessful outcomes seems to be due to differing interpretations given to World Health Organization definitions.

Outbreaks of food borne diseases in the Lazio region, Italy: the results of epidemiological field investigations.

BACKGROUND: More thorough information about risks, exposures and vehicles of food borne diseases can be obtained from epidemiological field investigations than from infectious disease reports or laboratory data. METHODS: We analysed the results of 410 field investigations of food borne disease outbreaks reported from 1996 to 2000 and conducted as cohort studies. RESULTS: The incidence of food borne outbreaks increased from 0.8/100,000 in 1996 to 2.0 in 1999, as did the incidence of salmonellosis (from 16/100,000 to 21 in the same period) and diarrhoea episodes reported by laboratories (from 12/100,000 in 1997 to 29 in 1999). Of the food borne disease outbreaks, 264 (64.4%) occurred in private homes; 5 (1.2%) in hospitals; 31 (7.6%) in canteens and refectories, 84 (20.5%) in restaurants, 41 of which occurred during special functions. The home outbreaks exposed few people (average of 7), had high attack rates (61.7% average) and a high proportion of known aetiology (66%), while food borne disease outbreaks in canteens and restaurants (during special functions) exposed many people (300 and 81, respectively), had medium attack rates (19.7 and 34.5%, respectively) and a higher proportion of confirmed vehicles (50 and 49%, respectively), compared to those occurring at home (21%). Salmonella spp. was the most frequent agent detected in each setting (67% of confirmed cases). The most frequent vehicles at home were mushrooms and sweets containing eggs and cream; in canteens, meat and vegetables and in restaurants, shellfish. CONCLUSIONS: Outbreak characteristics varied according to the setting. This implies the need for a different approach of field investigations, and different preventive measures.

An epidemic of gastroenteritis and mild necrotizing enterocolitis in two neonatal units of a University Hospital in Rome, Italy.

In the summer of 1999 a cluster of 18 cases of necrotizing enterocolitis (NEC) occurred in a University Hospital in Rome, Italy. The cases presented with mild clinical and radiological signs, and none died. Seventy-two per cent had a birth weight of > 2500 g, 66.7% had a gestational age of > 37 weeks, 30% presented with respiratory diseases and/or hypoglycaemia. All cases occurred within 10 days of birth and between 5 and 7 days after two clusters of diarrhoea (14 cases). The NEC outbreak had two phases; most cases in the first phase occurred in the at-risk unit, whereas those in the second phase occurred in the full-term unit. In the multivariate analysis, invasive therapeutic procedures, pathological conditions and formula feeding were associated with NEC. Although no predominant common bacteria were isolated, we suggest an infective origin of this outbreak.

Immunological changes among farmers exposed to phenoxy herbicides: preliminary observations.

OBJECTIVES: To evaluate short term immunological changes after agricultural exposure to commercial formulations of chlorophenoxy herbicides. METHODS: Blood samples were collected from 10 farmers within seven days before exposure, one to 12 days after exposure, and again 50 to 70 days after exposure. Whole blood was used to count lymphocyte subsets with monoclonal antibodies. Peripheral blood mononuclear (PBM) cells were used to measure natural killer (NK) cell activity and lymphocyte response to mitogenic stimulations. Values before exposure were used as reference. RESULTS: In comparison with concentrations before exposure, a significant reduction was found one to 12 days after exposure in the following variables (P < 0.05): circulating helper (CD4) and suppressor T cells (CD8), CD8 dim, cytotoxic T lymphocytes (CTL), natural killer cells (NK), and CD8 cells expressing the surface antigens HLA-DR (CD8-DR), and lymphoproliferative response to mitogen stimulations. All immunological values found 50-70 days after exposure were comparable with concentrations before exposure, but mitogenic proliferative responses of lymphocytes were still significantly decreased. CONCLUSIONS: According to our data agricultural exposure to commercial 2,4-dichlorophenoxyacetic acid (2,4-D) and 4-chloro-2-methylphenoxyacetic acid (MCPA) formulations may exert short term immunosuppressive effects. Further studies should clarify whether the immunological changes found may have health implications and can specifically contribute to cancer aetiology.

Factors associated with hepatitis B virus immunization coverage at the beginning of a population campaign in the Lazio region, Italy.

BACKGROUND: The hepatitis B virus (HBV) vaccination was introduced in Italy in 1991 as compulsory among newborns and among 11-year-old children. METHODS: We conducted a retrospective study to evaluate the HBV immunization coverage of the two target populations by the public health services in the Lazio region and to analyze factors associated with starting and completing HBV immunization in the initial period of the campaign. We used data registered in the public health services of 7/51 Health Districts. As a proxy indicator of services' performance we used the "expected immunization period," that is, the 6-month period in which each child should have been started on immunization, according to the calendar. RESULTS: HBV vaccine coverage rates were 63% in the younger cohort and 50% in the older one. The results of univariate and multivariate regression analysis showed that starting HBV immunization was associated with being newborn (crude OR = 3.30; 95%CI 2.17-2.44), with living in a small city (crude OR = 6.81; 95%CI 6.12-7.58), and with being assigned to the second (crude OR = 1.77; 95%CI 1.65-1.90) or to the third 6-month period of the expected immunization period (crude OR = 2.58; 95%CI 2.42-2.76). The probability of completing HBV immunization was higher among children who had had the first dose "age-appropriately" or with "acceptable delay" and among those living in small cities. It was lower among children in the second or the third 6-month period. Size of urban area of residence was associated with both outcomes: the city of Rome showed the lowest probabilities of starting and completing HBV immunization, while the small cities showed the highest ones. CONCLUSIONS: The performance of public health services was the most important determinant of recourse to public health services for vaccinations; it varied according to size of urban area; in towns organization difficulties contributed to the delay of starting vaccination, for at least a year. The expected immunization period was a good proxy indicator of services' performance. The timing of the first dose was the strongest predictor of completing vaccination also at the beginning of the campaign.

Estimating incidence of bacterial meningitis with capture-recapture method, Lazio Region, Italy.

To estimate the incidence of bacterial meningitis in the Lazio Region, including the city of Rome, and to assess the quality of the surveillance systems, we adopted a multiple-capture model by merging cases from three sources available in 1995-1996: the Notifiable Disease Surveillance (NDS) system, the Special Hospital Surveillance (SHS) system and the Hospital Discharge (HD) registry. A medical record revision was carried out to confirm the cases of bacterial meningitis. A total of 199 individuals was classified as probable or confirmed cases of bacterial meningitis in 1995-1996. In this period, the incidence of reported meningitis was 3.8/100,000 (population = 5,209,633). The log-linear model yielded a total estimated number of 236 cases (95% confidence interval (CI): 206-306), the estimate of incidence reaching the value of 4.5/100,000. Hospital Discharge registry showed the highest sensitivity (77%), the SHS system the highest positive predictive value (83%). In 1997-1998, the meningitis surveillance was integrated with an additional laboratory-based source and yielded 326 cases, with an incidence of reported cases of 6.3/100,000. Laboratory surveillance, involving 115 (92%) public hospitals and 84 (57%) private clinics, contributed 35 (27%) cases in addition to those notified to NDS (n = 130). Multiple-capture models, in our experience could estimate the bacterial meningitis incidence with a very good approximation. In order to improve both sensitivity and positive predictive value of surveillance, hospital and public health sources should be integrated with laboratory-based system.

Persistence of anti-HBs 5 years after the introduction of routine infant and adolescent vaccination in Italy.

A population survey was conducted to assess the duration of anti-HBs levels > 10 IU/l in vaccinees living in Lazio Region (Italy) 5 years after the introduction (15 June 1991) of compulsory vaccination of new-borns and 11-year-old children. A random sample of 1192 (533 children born in 1991--92 and 659 adolescents born in 1979--81) was selected. In 92.9% of children and 94.1% of adolescents anti-HBs titres were protective (> or = 10 IU/l). These subjects with protective titres were divided into three categories: low responders (anti-HBs titres = 10--500 IU/l), medium responders (anti-HBs titres = 501--2000 IU/l) and high responders (anti-HBs titres > 2000 IU/l). Factors associated with the level of response were analysed, using a multiple politomic logistic regression analysis. Greater age at first dose (11--12 years) was associated with higher titres (OR = 2.1, 95% CI = 1.4--3.2 for medium responders and OR = 3.0, 95% CI = 1.9--4.8 for high responders). Simultaneous administration of DT vaccine was associated with lower titres (OR = 0.4, 95% CI = 0.2-0.8 for medium responders and OR = 0.3, 95% CI = 0.1--0.7 for high responders).