Giovanni Milan

Pattern and determinants of hospitalization during heat waves: an ecologic study

BackgroundNumerous studies have investigated mortality during a heatwave, while few have quantified heat associated morbidity. Our aim was to investigate the relationship between hospital admissions and intensity, duration and timing of heatwave across the summer months.MethodsThe study area (Veneto Region, Italy) holds 4577408 inhabitants (on January 1st, 2003), and is subdivided in seven provinces with 60 hospitals and about 20000 beds for acute care. Five consecutive heatwaves (three or more consecutive days with Humidex above 40°C) occurred during summer 2002 and 2003 in the region. From the regional computerized archive of hospital discharge records, we extracted the daily count of hospital admissions for people aged ≥75, from June 1 through August 31 in 2002 and 2003. Among people aged over 74 years, daily hospital admissions for disorders of fluid and electrolyte balance, acute renal failure, and heat stroke (grouped in a single nosologic entity, heat diseases, HD), respiratory diseases (RD), circulatory diseases (CD), and a reference category chosen a priori (fractures of the femur, FF) were independently analyzed by Generalized Estimating Equations.ResultsHeatwave duration, not intensity, increased the risk of hospital admissions for HD and RD by, respectively, 16% (p < .0001) and 5% (p < .0001) with each additional day of heatwave duration. At least four consecutive hot humid days were required to observe a major increase in hospital admissions, the excesses being more than twofold for HD (p < .0001) and about 50% for RD (p < .0001). Hospital admissions for HD peaked equally at the first heatwave (early June) and last heatwave (August) in 2004 as did RD. No correlation was found for FF or CD admissions.ConclusionThe first four days of an heatwave had only minor effects, thus supporting heat health systems where alerts are based on duration of hot humid days. Although the finding is based on a single late summer heatwave, adaptations to extreme temperature in late summer seem to be unlikely.

Epidemiologic evidence of cancer risk in textile industry workers: a review and update.

A meta-analysis of epidemiologic studies for textile industry workers was undertaken in an attempt to evaluate whether the cancer risk varies within the textile industry in relation to the job held or the textile fiber used. We combined studies published up until 1990, when an ad hoc IARC Monograph was issued, and those published after 1990 with the aim of appreciating evidence of reversing trends in cancer risk. Observed and expected cases reported in the original studies were summed up and the totals were divided to obtain a pooled relative risk (PRR) with a 95% confidence interval (CI) estimated with a fixed-effect model. We calculated a chi-square test (x2) of heterogeneity among studies. When PRR and x2 were both significant, PRR and CI were calculated with a random-effect model and the source of heterogeneity was investigated. Lung cancer risk was around 0.4 in the first study on cotton workers published in 1936, around 0.7 in subsequent studies, mostly published in the 1970s and 1980s, and around 1.0 in the last studies published in the 1990s. Papers published in the 1970s and 1980s produced consistent risk estimates for lung cancer risk, which was significantly lower than 1.0 in workers exposed to cotton (PRR 3/4-0.77; CI3/4-0.69-0.86) and wool dust (0.71; 0.50-0.92), as well as in carders and fiber preparers (0.73; 0.54-0.91), weavers (0.71; 0.56-0.85), and spinners and weavers (0.78; 0.66-0.91). Lung cancer PRRs did not significantly deviate from 1.0 in textile workers using synthetic fibers or silk, and in dyers. Increased PRRs were found for sinonasal cancer in workers exposed to cotton dust, and in workers involved in spinning or weaving (4.14; 1.80-6.49). PRR was 1.46 (1.10-1.82) for cancer of the digestive system in textile workers using synthetic fibers or silk, and 1.34 (1.10-1.59) for colorectal cancer in spinners and weavers. The increased bladder cancer PRR in dyers (1.39; 1.07-1.71) is generally attributed to textile dye exposure. In studies published after 1990, there is a general tendency to move toward unity for all the cancer risk estimates, leading to an increasing heterogeneity among studies. Since adjustment for smoking made little difference to the findings, the latter could be attributed to the exposure to textile dusts. The recent findings could be due to a lowering of dust concentration in the workplaces. The reduction of cases of upper respiratory tract cancer parallels with a corresponding increase of lung cancer cases. So, preventive measures have paradoxically increased the lung cancer burden to the textile workers.

Measuring Accuracy of Discharge Diagnoses for a Region-Wide Surveillance of Hospitalized Strokes

Background and Purpose— Measuring the impact of stroke through population-based stroke registers is complex and costly. The aim of the present study is to assess the validity of hospital discharge diagnoses (all ages) and to estimate the total number of hospitalized stroke events in the Veneto region (Northeastern Italy, 4 500 000 inhabitants). Methods— All discharges covering a 1-year period (1999) from Veneto hospitals with International Classification of Diseases, 9th Revision codes 342, 430 to 434, and 436 to 438 were identified. A stratified sample was extracted and submitted to retrospective clinical record review according to the World Health Organization MONItoring trends and determinants in CArdiovascular disease stroke project. Using the positive predictive value (PPV) for validated acute stroke of each code to adjust for inaccuracy of discharge diagnoses, an estimate of hospital strokes was obtained. Results— 4015 admissions were reviewed. Codes 430, 431, 434, and 436 as primary diagnoses had the highest PPV, which sharply decreased in the other diagnostic levels. Code 342 also showed a high PPV. The probability of suspected events meeting the stroke definition increased with age and was highest for patients admitted to neurological wards and for fatal events. Overall 9400 strokes (first-ever and recurrent) were estimated to be hospitalized in 1999, with an attack rate of 208 per 100 000. Conclusions— Our data indicate that once validation studies are undertaken on a sample of all hospitalized events, hospital discharge records can provide a valuable source of information on the actual burden of strokes on hospital services.

Lung cancer risk in workers exposed to poly(vinyl chloride) dust: a nested case-referent study

Background: There have been few investigations of an association between poly(vinyl chloride) (PVC) dust exposure and an increase in lung cancer incidence, and their conclusions have been inconsistent. Aims: To determine whether PVC and/or vinyl chloride monomer (VCM) is the associated risk factor(s), by means of a nested case-referent study, in order to estimate lung cancer risk, avoiding selection, information, or confounding biases. Methods: Thirty eight cases of histologically verified lung cancer and 224 control subjects without a history of cancer were selected from an Italian cohort of 1658 vinyl chloride workers. Information sources included clinical records (diagnosis, smoking habits) and plant records (occupational history). The risk of lung cancer was estimated by odds ratios (OR) with 95% confidence intervals (CI), calculated using logistic regression models. Results: In PVC baggers exposed to high levels of respirable PVC particles in the workplace, the lung cancer OR increases by 20% for each extra year of work (OR = 1.2003; 95% CI 1.0772 to 1.3469; p = 0.0010), when the influence of age and smoking habits is controlled. No relation was found between lung cancer and cumulative VCM exposure. Conclusion: This nested case-control study showed, in the VCM/PVC industry, an increased risk of lung cancer associated with exposure to PVC dust; previous cohort studies failed to recognise such excess, probably because they used VCM exposure as the risk indicator.

Sustainability of the effects of the demerit points system on seat belt use: a region-wide before-and-after observational study in Italy.

To assess the short and long term effects of the demerit points system on seat belt use, we set a region-wide cross-sectional observational study 3 months before, and 3 and 15 months after the introduction of the scheme (July 2003) in the Veneto Region, Italy. We analysed differences in seat belt use by year of observation, gender and position in the vehicle, and obtained adjusted prevalence ratio (APR) through Poisson regression. A total of 29,303 drivers, 28,778 front and 12,186 rear passengers were observed. Prevalence levels of 54% for drivers and 53% for front passengers in 2003 switched to 83 and 76%, respectively, 3 months after the new legislation, with further slight increases 15 months thereafter. Seventy-four percent rear passengers were still not compliant with the legislation in 2005. The probability of being belted was 25% lower in males than females (APR=0.75, 95% CI 0.73-0.77) at the beginning of the study period. However, the effect of the new legislation was 19% greater among males (APR=1.19, 95% CI 1.16-1.23). A substantial increase in seat belt use was reached and sustained with the demerit points system. Specific efforts should target rear passengers whose seat belt use still remains worryingly low.

Cancer increased after a reduction of infections in the first half of this century in Italy: Etiologic and preventive implications

Two rate ratios indicating the disappearance of infections and the growth of tumours, respectively, were simultaneously plotted against the calendar years of occurrence in a period during which mortality rates were reasonably comparable to incidences. The transformation used gave upward trend time variations for infectious diseases, providing strong evidence that in Italy during the first half of this century variations in infectious diseases preceded variations in cancer. While some bacteria and viruses are known to be cancer agents, sparse studies indicate that a hosts immune response to infection may destroy cancer cells. With a decreasing mortality from infectious illnesses, there may have been a reduction in the activation of immunological mechanisms against transformed cells in early phases of carcinogenesis. If cancer growth is a consequence of a lower exposure to chronic sublethal doses of microbial agents, bacterial derivates could be potentially useful in cancer chemoprevention.

Lung and other cancer site mortality in a cohort of Italian cotton mill workers

Background: Several studies report a lower than expected mortality in lung cancer among workers exposed to organic dust. Recent studies also reported a decreased risk for cancer at other sites. Objectives: To evaluate the mortality from lung and other cancer sites in cotton mill workers. Material and methods: A cohort of 3961 Italian cotton mill workers was divided into those working with carding (exposed to high levels of endotoxin-containing cotton dust) and other tasks, which generally have lower exposure. Standardised mortality ratios (SMRs), with 95% confidence intervals (CI), were calculated using death rates of the regional general population as a reference. Cancer mortality was analysed in relation to the length of employment in the two task groups. An internal analysis was also performed through Poisson regression. Results: Among workers in carding departments, lung cancer SMRs were 1.88 (CI: 0.69 to 4.08), 1.01 (CI: 0.20 to 2.94) and 0.22 (CI: 0.00 to 1.24), respectively, for <6, 6–12 and >12 years of employment (χ2 for trend = 5.45; p<0.05). A significant (p = 0.04) trend was confirmed by Poisson regression. No reduced risks were found for other forms of cancer, nor for those working with other tasks. Conclusions: The results support previous reports that a high and prolonged exposure to cotton dust and other endotoxin-containing organic dusts is related to a lower risk of lung cancer. There was no indication of a reduced risk for other forms of cancer.

Effect of the new diagnostic criteria for ST-elevation and non-ST-elevation acute myocardial infarction on 4-year hospitalization: an analysis of hospital discharge records in the Veneto Region.

Objective To assess the burden of hospitalization for acute coronary syndrome (ACS) and the impact of the new diagnostic criteria for acute myocardial infarction on epidemiology of ACSs. Methods We analysed the hospital discharge record archives of the Veneto Region in the period 2000–2003, including admissions of regional residents outside the study area. We defined a list of ICD-9-CM codes for the identification of different types of ACS. We examined trends in standardized hospitalization rates as well as patient characteristics (age, sex) and pattern of care (setting, invasive revascularization, length of hospital stay, in-hospital mortality). Results The hospitalization rate for non-ST-elevation myocardial infarction increased by about 70%, with a parallel decrease in hospitalizations for unstable angina, whereas the hospitalization rate for ST-elevation myocardial infarction remained unchanged. These trends are likely influenced by the new diagnostic criteria for acute myocardial infarction. At the end of the study period, although the main patient characteristics did not vary substantially, the pattern of care turned out to be more aggressive. Conclusions Despite some limitations, our results indicate that the new diagnostic criteria for acute myocardial infarction have a major impact on epidemiological evaluation. These data may be relevant when comparing epidemiological data of different periods and planning healthcare policies. Further studies are needed in order to evaluate the accuracy of ICD-9-CM codes in the diagnosis of ACSs.

Hospital care services for digestive diseases in Italy: the first quantitative assessment.

The scarcity of human and structural resources for specialized gastroenterology care is a problem in many Western countries. Data regarding the resources for Italian Gastroenterology, so far lacking, have been thus searched and evaluated. Based on an agreement protocol between the Italian Association of Hospital Gastroenterologists and Endoscopists (AIGO) and the Ministry of Health, national data regarding all Institutions providing gastroenterological care were analysed. Hospital beds in Gastroenterology units are presented by region, regimen of stay and per million inhabitants as of January 2011. Association of Hospital Gastroenterologists and Endoscopists also performed a survey of gastroenterology units in all Italian regions regarding number of ordinary/day hospital beds and the number of staff gastroenterologists. The Ministry data showed a total of 174 Gastronterology Units in Italy, a total of 2062 hospital beds for the discipline, for a proportion of 34.2 beds per million inhabitants. The Association of Hospital Gastroenterologists and Endoscopists survey showed a total of 1425 gastroenterologists in Italy. These data should represent a key reference for appropriate planning of specialized care for digestive diseases.