Total parenteral nutrition is associated with worse hospital outcomes among elderly diabetic patients: a propensity score matched analysis on discharge records

Background

Recent trials and reviews have raised question about the safety of total parenteral nutrition (TPN), due to the increased rate of TPN related complications. Diabetic patients are vulnerable to hyperglycaemia, and poor studies have investigated hospital out-comes of diabetic patients requiring TPN. The aim of this study was to evaluate the association of in-hospital mortality, prolonged length of stay and transfer to long-term care facilities among diabetic patients with TPN.

Methods

The study considered all hospital admissions of diabetic patients over 65 years of age performed between 2006 and 2015 in Abruzzo Region, Italy. To compare the outcomes of TPN and non-TPN patients, a propensity score matching procedure was performed.

Results

A total of 140,556 admissions were analyzed. After matching, 1947 patients were included into the analyses: 649 patients with TPN and 1298 controls. TPN was significantly associated to in-hospital mortality (OR=7.15; 95%CI 5.54-9.22), prolonged LOS (OR=2.78; 95%CI 2.28-3.38) and transfer to LTCF (OR=2.16; 95%CI 1.64-2.85).

Discussion

TPN is associated with poor outcomes among elderly diabetic patients in the Italian setting. Being aware of the risk factors among diabetic patients with TPN can be used to anticipate the patients' needs during the admission and the immediate post-discharge period.

Comparison of admissions for Acute Coronary Syndrome between 2020 and two control periods in Abruzzo

Background

The coronavirus epidemic has put unprecedented strain on health services, threatening hospital capacity in facing such a high number of Covid-19 patients in need of treatment. The aim of this study is to compare the hospitalization rate for acute coronary syndrome (ACS) in the first nine months of 2020 with the same period of 2018 and 2019.

Methods

This is a retrospective study of hospital discharge records. The pathologies of interest were coded as follows: all the hospitalizations with main discharge diagnosis as ICD-9-CM 410.xx, 411.xx, 413.xx for Acute Coronary Syndrome (ACS); 410.xx was used in all diagnoses except in codes 410.7x or 410.9x for acute ST-elevation myocardial infarction (STEMI); 410.7x was used in all diagnoses except 410.9.x for acute non-STEMI. Hospitalization rate ratios (HRR) comparing the study period with each of the control periods were calculated using Poisson regression.

Results

During the study period there was a statistically significant decrease in hospitalizations for ACS both vs 2018 (HRR 0.80;95%CI 0.80-0.81; p < 0.001) and vs 2019 (HRR 0.85;95%CI 0.84-0.86; p < 0.001). A decrease also affected STEMI vs 2018 (HRR 0.91;95%CI 0.90-0.92; p < 0.001) and vs 2019 (HRR 0.87;95%CI 0.86-0.88; p < 0.001) and NSTEMI vs 2018 (HRR 0.76;95%CI 0.75-0.77; p < 0.001) and vs 2019 (HRR 0.79;95%CI 0.78-0.80; p < 0.001).

Conclusions

This report shows a significant decrease in ACS-related hospitalization rates across the Region during the study period. General out-of-hospital mortality need to be further investigated, as to focus on patients died of ACS without receiving adequate assistance from the emergency network.

Key messages

Hospitalizations for acute coronary syndromes, STEMI and NSTEMI underwent a statistically significant decrease.

During the pandemic, some health needs related to fatal emergencies were not met by the health services.

The Indirect Impact of Covid-19 Pandemic on Hospitalizations for Cardiovascular Diseases in Abruzzo

Background

In 2020 the Covid-19 pandemic influenced the organization of all health systems, imposing new rules for accessing the hospitals and delaying or reducing the ability to cope with all the population needs. In addition, people with life-threatening conditions deferred care for their fear of contagion. The study aimed to evaluate the indirect impact of Covid-19 on hospitalization rates for cardiovascular diseases in 2020 in Abruzzo.

Methods

Data were obtained from the hospital discharge records of all Abruzzo. We analyzed all the hospitalizations included in Major Diagnostic Categories 5 (cardiovascular diseases). First, we distinguished both between public or private hospitalizations and ordinary or day-hospital admissions. Second, we compared the first nine months of 2020 with a mean of the same months in the two previous years. Finally, we calculated the variable percentage.

Results

A huge reduction in hospitalization in MCD 5 contest was observed in each subgroup. Specifically, ordinary regimen had a peak of -56,4% in April. Day-hospital admissions were the most affected by Covid-19 with a peak of -84% in April. The largest reduction in hospitalizations occurred in private hospitals, in both ordinary (-81% in April) and DH admissions (-100% in April). A rebound in admissions was reported only for ordinary private regime between June and September, with a peak of + 24% in August.

Conclusions

Covid-19 had a severe impact on Abruzzo hospitalizations. The medical conditions that we examined needed effective hospital treatment to avoid adverse outcomes or death. Subsequently, fewer hospitalizations for such medical conditions were almost certainly associated with patient harm. Despite the pandemic, health system leaders should manage to provide subjects with hospital care, when necessary.

Key messages

Covid-19 had a significant indirect impact on the rate of hospitalizations for cardiovascular disease in Abruzzo.

Despite the pandemic, regional health systems should manage to provide effective hospital care for patients with cardiovascular conditions that require hospitalization.

Differences in COVID-19 mortality between pandemic phases in a southern Italian region

Background

Overall mortality is a relevant indicator of the population burden during COVID-19 pandemic, reflecting the overload and preparedness of the healthcare system. This study aimed to analyse the distribution of deaths in SARS-CoV-2 positive patients between pandemic phases and to evaluate the characteristics of COVID-19 patients deceased during the year.

Methods

Data on confirmed COVID-19 cases were collected from the recording system of the Department of Prevention of the Local Health Authority of Abruzzo Region, Italy. The course of the epidemic was stratified in 4 phases: the first wave (March-May 2020), the low incidence phase (June-September 2020), the second wave (October 2020-December 2021), and the variants spread phase in our region (January-March 2021).

Results

From March 2020 to March 2021 we registered 17,082 cases of SARS-CoV-2 infection, of these patients 571 (3.35%) had a fatal outcome. The mortality was the highest during the first ‘peak' phase, interesting the 14.20% of the notified cases, and the lowest during the last phase (2.50%). Mortality due to COVID-19 mainly affected men (54.99%) and geriatric patients (median age: 84; IQR: 75-90). Women dying for SARS-CoV-2 infection had a more advanced median age (87; IQR: 79-92) than men (81; IQR: 73-87). The lowest median age was registered in patients deceased during the low incidence phase (75.5; IQR: 71-82). The median time span, in days, from a SARS-CoV-2 positive test to death was significant lower in the phase 1 (days:10; IQR:4-20) then in phase 4 (days:14; IQR:8-22) (p < 0.001).

Conclusions

Our results showed that mortality markedly decreased during the COVID-19 epidemic, and this could be likely related to an improved organisation and delivery of care, in addition to a better knowledge of disease treatment. Elderly patients were more likely to progress toward fatal outcome. The healthcare systems should pay special attention to them in order to effectively manage possible future pandemics.

Key messages

The COVID-19 mortality reduction highlights an improvement of health care; the elderly remains at major risk of death.

Providing pandemic prevention and care models focused also on vulnerable groups is a major public health challenge.

Reduction in Neurological Disease Hospitalization Rate During Covid-19 Pandemic in Abruzzo

Background

As a consequence of the Covid-19 outbreak, Italy has adopted unprecedented preventive measures such as large-scale application of social isolation and hospital rearrangements. These measures have led to difficulty in managing diseases and hospitalizations, particularly acute and severe conditions such as neurological morbidities. The aim of the present analysis is to investigate the change in hospital admissions for neurological diseases over the first nine months of 2020 in Abruzzo region.

Methods

Data were obtained from the Hospital Discharge Records of all Abruzzo. We analyzed all the hospitalizations included in Major Diagnostic Categories 1 (neurological diseases). First, we distinguished both between public or private hospitalizations and ordinary or day-hospital admissions. Second, we compared the first nine months of 2020 with a mean of the same months in the two previous years. Finally, we calculated the variable percentage.

Results

A huge reduction in MCD 1 series hospitalizations was observed in each subgroup. Specifically, ordinary regimen had a peak of -47,3% in April. Day-hospital admissions were the most affected by Covid-19 with a peak of more than 90% in April both in public and private hospitals. The largest reduction occurred in private hospitals, both in ordinary (-75% in April) and DH admissions (-93,8% in March).

Conclusions

Despite the severity of the diseases included in MDC 1 (i.e. ischemic stroke, intracranial hemorrhage), a significant decline was detected in hospital admissions in Abruzzo. Subsequently, a high number of subjects might have not received the necessary health assistance leading to an increase in mortality and morbidity for these severe pathologies. Additionally, patients might have avoided seeking hospital care in response to the fear of contagion triggered either by media or as a result of the stay-at-home government recommendations.

Key messages

An alarming reduction in all types of hospitalizations for neurological diseases occurred over the first months of pandemic in Abruzzo.

Greater management efforts are needed to reduce the morbidity and mortality rates associated with the reduced hospital admissions during the pandemic.

Vaccination coverage after the introduction of mandatory law: results from an Italian Southern Region

Background

Over the latest decades, Europe has been facing the spreading of vaccine hesitancy. This growing phenomenon has resulted in decreasing vaccination coverage all over Europe, particularly in Italy for measles, mumps and rubella. In order to face up this problem, in 2017 Italy introduced compulsory vaccination against 10 different infectious diseases: diphtheria, tetanus, pertussis, polio, hepatitis B, haemophilus influenzae B (all included in the hexavalent vaccine), measles, mumps, rubella (included in the MMR vaccine) and chickenpox (from the 2017 cohort). The aim of this study was to evaluate vaccination coverages in 2019 in Abruzzo, an Italian Southern Region, after the introduction of compulsory vaccinations.

Methods

In this study the following indicators were taken into account: vaccination coverages at 24 months of age (2017 cohort of birth), vaccination coverages at 36 month of age (2016 cohort), vaccination coverages at 5/6 years of age (2013 and 2014 cohorts) and vaccination coverages at 16 and 18 years of age (2001 and 2003 cohorts). Vaccination coverage rates were calculated as the number of vaccinated patients for each disease over the total number of patients born in the year considered.

Results

At the end of 2019, the 2017 cohort reached 95% coverage for all vaccinations except for chickenpox (87.9%). Conversely, the 2016 cohort showed low rates for MMR and chickenpox, up to 90.8% and 52.1% respectively. Additionally, 2013 and 2014 teenager cohorts showed coverage rates lower than 95% for all the compulsory vaccinations.

Conclusions

After two years of mandatory vaccination law in Italy, vaccination coverages have reached the 95% threshold only among patients of 24 months of age. Older cohorts still show inadequate vaccination coverages despite the introduction of mandatory vaccination law. Health services at regional level should develop policies and strategies aiming to improve vaccination coverages and to reach herd immunity.

Key messages

After the introduction on mandatory vaccination, vaccination coverages reached the 95% threshold only among patients of 24 months of age. Health services should develop strategies aiming to improve vaccination coverages.

Attitudes towards COVID-19 preventive measures: an Italian cross-sectional study

Background

The outbreak of COVID-19 was declared Public Health Emergency of International Concern on the January 2020. During an infectious disease outbreak, non-pharmaceutical interventions are essential to delay an epidemic peak and to flatten the epidemic curve, in order to wait for vaccine development. Perception or beliefs may be essential in determining adherence to official recommendations. The aim of this study was to assess whether perceptions of COVID-19 and awareness of preventive strategies effectiveness were associated to behavioural changes.

Methods

Web-based survey was performed in Italy between the 9 and the 15 March 2020. The survey contained six sections: subject's demographics, subject's behaviours during the latest three weeks, subject's behaviours during the latest 24 hours, perceived efficacy of behaviours, awareness raised by the government-led prevention campaign for COVID-19 and co-occurring anxiety.

Results

1912 participants were enrolled in the study. 48.1% of the participants (n = 919) reported to perform at least 7 preventive behaviours. Most people reported a change in the frequency of their hand-washing (94.7%), an increment in the frequency of surface cleaning and disinfecting (58.9%), and a reduction in the use of public transport (92.5%). Behavioural changes were related to an increase in the anxiety level (OR 1.47; 95%CI 1.16-1.87). After adjusting for personal characteristics and anxiety, an association resulted between clear perception of COVID-19 high infectiousness (OR 1.25; 95%CI 1.00-1.59) and of its severe consequences (OR 1.29; 95%CI 1.05-1.59), clearness of communication about the virus (OR 1.41; 95%CI 1.17-1.71), and increased likelihood of performing the recommended behavioural changes.

Conclusions

To better protect people against future epidemics, health-promotion efforts should be aimed at increasing the level of awareness towards infectious diseases and at implementing and encouraging non-pharmaceutical interventions.

Key messages

Clear perception of COVID-19 high infectiousness and of its severe consequences are associated with an increased likelihood of performing the recommended behavioural changes.

Health promotion strategies should be a critical part of infection prevention and control program.

The impact of gender on diabetes-related lower extremity amputations: An Italian regional analysis on trends and predictors

BACKGROUND

Diabetes-related lower extremity amputations (LEAs) are a major public health issue. The aim of the study was to evaluate trends by gender and predictors of LEAs in an Italian region.

METHODS

Data were collected from hospital discharge records between 2006 and 2015. Gender- and age-adjusted standardised hospitalisation rates for major and minor amputations were calculated. Poisson regression model was performed to estimate trends in LEAs.

RESULTS

Hospitalisation rates decreased for minor amputations both among males (-30.0%) and females (-5.3%), while the major amputation rates decreased only for males (-44.7%). Males were at higher risk of undergoing major (IRR 1.41, 95%CI 1.19-1.67) and minor (IRR 1.62, 95%CI 1.45-1.82) amputations. Peripheral vascular disease was the leading predictor of major and minor amputations.

CONCLUSION

A significant reduction of LEAs was observed only for males. Identifying their predictable factors may help caregivers to provide higher standards of diabetes care.

Norovirus foodborne outbreak in an agritourism: causes, development and legal consequences

Background

Norovirus is the main causative agent of viral acute gastroenteritis. It is easily transmitted and frequently causes foodborne and waterborne outbreaks. The Food Hygiene Service of ASL 2 Abruzzo received notification of gastrointestinal illness in 33 customers who attended a lunch at an agritourism on 28 July 2019.

Methods

The investigation started immediately. The event was reported to the Judicial Authority and food preparation was suspended. Stool specimens and rectal swabs were collected from 18 guests and 2 food handlers and tested. A questionnaire survey was given to the customers. During the inspection, the Food Hygiene Service sampled some food leftover and water from faucets. Furthermore, it found an incomplete HACCP manual.

Results

The 31 cases of gastrointestinal illness occurred within 12-72 hours and didn't need hospitalization. Among the affected subjects,18 were men (58.1%) with a median age of 51 years. All the biological samples collected from the subjects were positive for Norovirus GII, as revealed by Real Time-PCR. The two food handlers resulted positive for Norovirus GII, but they were asymptomatic. They were tested up to 3 weeks after the outbreak and their feces remained positive. Water and food samples resulted negative, except for raw ham's outer surface, that resulted positive for Norovirus GII. The contamination probably occurred during food preparation.

Discussion

This outbreak was related to food cross-contamination by infected food handlers, likely caused by a failure in application of both personal and food hygiene measures prescribed in HACCP plan. Food preparation restarted on 12 September 2019, but infected food handlers were dismissed until they were positive. The Judicial Authority will file a lawsuit against the food operator business that could lead to imprisonment or fines.

Key messages

Norovirus outbreaks are recognized as a public health concern causing a high number of cases and serious health consequences in children and the elderly. HACCP manual must be customized for each food business and integrally applied by food handlers in order to attain a higher standard of food safety for prevention of foodborne illness.

Rotavirus gastroenteritis hospitalization in children. Trends in Abruzzo Region, 2008-2018

Background

Rotavirus is the most important cause of hospitalization for gastroenteritis and dehydration in children under 5 years old. In developed countries, it significantly affects public health in terms of costs and morbidity. Despites the availability of an effective vaccine, the coverage remains low in Italy. This study aimed to evaluate the epidemiological impact of rotavirus hospitalizations in Abruzzo, an Italian region, from 2008 to 2018.

Methods

Data were obtained from hospital discharge records of all Abruzzo hospitals. For the study, only the admissions due to rotavirus infection occurring in children aged 0 to 5 over the study period were taken into consideration. For each year, age-adjusted standardized hospitalization rates for rotavirus infection were calculated, and time trends were analyzed by joint point regression models.

Results

A total of 747 admissions were identified. During the study period, a significant increase of admissions was observed among children under 1 year of age (AAPC +9.8%, 95%CI 0.0;20.5, p &lt; 0.001) and a significant decrease was observed among children between 2 and 3 years of age (AAPC -10.6%, 95%CI -20.0; -0.1, p &lt; 0.001). Overall, the standardized rate increased (AAPC +5.2%, 95%CI -3.0;14.1, p = 0.2).

Conclusions

These results confirm that Rotavirus gastroenteritis has a heavy impact on pediatric hospitalization in Abruzzo Region. Subsequently, the study gives evidence of the need to improve vaccination coverage, in order to reduce morbidity and costs for the Italian healthcare system.

Key messages

In Abruzzo region, rotavirus gastroenteritis is a very important cause of morbidity and hospitalization in children under 5 years old. This study confirms the need of an improvement in vaccination coverage, that is the most effective mean to reduce the high morbidity, as well as the social and health costs.

A novel tool to predict in-hospital mortality after hip-fracture: the PRIMOF score

Background

Increased life expectancy has led to an increased incidence of hip fractures in aged people. Patients reporting hip fractures often show relevant comorbidities leading to prolonged hospital stays, significant complications, and higher mortality rates. Being aware of the factors associated with in-hospital death or adverse events can help patients and healthcare providers make informed planning and management. The aims of this study were the development and validation of a score predicting in-hospital mortality among hip fractured patients.

Methods

Patients were selected from the hospital discharge record referring to the period 2006-15 and including data on the population aged 40 years or over in Abruzzo, a region of Southern Italy. The whole population was divided into 2 random samples in order to control the accuracy of predictions and to increase the reliability of all the statistical analyses. A multivariate logistic regression model was performed to identify the predictors of in-hospital mortality. All the diagnoses significantly associated with in-hospital mortality were included in the final model.

Results

The score ranged between 0 and 27 and was divided into four groups to facilitate the tool interpretation. An increase in odds ratio values was documented alongside the increase in PRIMOF score both in training and in validation groups. The score showed a good calibration and a good accuracy in predicting in-hospital mortality.

Conclusions

This study has shown that a simple score, based on the clinical history of the patient, allows to stratify the risk of hip fractured population in terms of in-hospital mortality. The identification of individuals at high risk of short-term death can be of great significance to health providers and public and private health services.

Key messages

Patients reporting hip fractures often show relevant comorbidities leading to higher in-hospital mortality rates. A simple score, based on the clinical history of the patient, allows to stratify the risk of hip fractured population in terms of in-hospital mortality.

Physical multimorbidity, mental health and unplanned admissions from 2008 to 2018 in Abruzzo region

Background

Multimorbidity is defined as the presence of more than one long-term disorder and it is associated with increased use of health services. Socioeconomic deprivation and mental health conditions may lead to undesirable additional unplanned admission to hospital (urgent or emergency admission). This study examines the association among unplanned admission, multimorbidity, mental health and socioeconomic deprivation for both preventable and not preventable hospitalization.

Methods

We conducted a retrospective analysis of hospital discharge records between 2008 and 2018 in Abruzzo, an Italian region. Multilevel logistic regression models were implemented for both preventable and not preventable unplanned admissions. We set as levels the district of residence and Local Health Authority. As independent variables we used the Italian Deprivation Index of the district of residence to mitigate socioeconomic inequalities, unweighted count of physical health conditions (0, 1, 2, 3, ≥4), the presence of a diagnosis of mental health condition. All the models were also adjusted for age and gender.

Results

We selected 2,017,720 non preventable admissions, 836,808 (41.45%) of which unplanned, and 152,938 preventable admissions, 107,336 (70.18%) of which unplanned. Both unplanned and potentially unplanned admissions were associated with increasing physical multimorbidity (for ≥4 v. 0 condition, OR 4.85; CI95% 4.26-5.53 for unplanned admission and OR 1.42; CI95% 1.11-1.83 for preventable unplanned admission) and with mental health conditions (OR 1.66; CI95% 1.57-1.75 for unplanned admission and OR 1.18; CI95% 1.00-1.38 for preventable unplanned admission).

Conclusions

Co-occurrence of physical multimorbidity and mental health condition was associated either with unplanned admission or unplanned preventable admission. Primary care interventions targeting multimorbidity are necessary to reduce the hospital service burden.

Key messages

Physical multimorbidity substantially affects the use of acute hospital services. Primary care interventions targeting multimorbidity are necessary to reduce the hospital service burden.

Pediatric ambulatory care sensitive admission and deprivation index, ten years retrospective analysis

Background

Ambulatory Care Sensitive Conditions (ACSCs) are conditions where effective community care and case management can help prevent the need for hospital admission. Even if the ACSC episode itself is managed well, an emergency admission for an ACSC is often symptom of overall poor quality of primary and community care. Lower socioeconomic status individuals show higher rates of hospitalization due to ACSCs. The purposes of this study is to examine the association between socioeconomic status and the risk of hospitalization due to an ACSC in pediatric population through a retrospective analysis of administrative data of the Abruzzo region.

Methods

We identified hospital discharge records from 2008 to 2018 of subjects under 18 years of age to take into consideration for the study. Hospitalizations due to ACSCs were selected by ICD9-CM coding developed by Billings et al. and implemented by Lu et al. For establishing the socioeconomic status, we used the Italian Deprivation Index (IDI) developed by Caranci et al. as a categorical variable expressed in quintiles. A multilevel logistic regression model was implemented using ACSC vs non ACSC hospitalization as dependent variables.

Results

In the study period, a total of 317,586 hospital discharge records were selected, 18059 (5.69%) of which related to ambulatory care sensitive hospitalization. After correcting for age, gender, and citizenship, ACSCs hospitalization was associated with lower IDI (aOR1.21;CI95%1.09-1.34) and a slight gradient as the deprivation increased. Moreover, it was also associated with emergency department admission (aOR6.53;CI95%6.19-6.89).

Conclusions

Avoidable hospitalization in pediatric settings is associated with lower socioeconomic status computed by IDI. This study confirms inequity in primary care or community care after adjusting for age, gender and citizenship. Italian deprivation index represents a useful tool to identify population and areas where improving prevention is necessary.

Key messages

The Italian deprivation index could be used to implement primary and community care strategies in pediatric settings. Socio-economic factors are associated with the performance of the health services.

Attitudes toward vaccination among healthcare workers: a cross-sectional study from Italy

Background

In Italy, the loss of confidence in vaccines has resulted in low vaccination coverage also among healthcare workers (HCWs). Low vaccination coverage among HCWs may lead to dangerous outbreaks and may increase absenteeism. The aim of this study was to investigate vaccine coverage and the attitudes toward vaccination among HCWs.

Methods

A multicenter cross-sectional study was conducted from August to November 2019 among HCWs referring to all the hospitals of the Local Health Authority 02 of Abruzzo Region, Italy. The survey was based on the questionnaire proposed by the H-ProImmune Project, aiming at investigating vaccination coverage and beliefs towards vaccination. Besides a descriptive analysis of the results, a logistic regression analysis was performed to evaluate the association between vaccine coverage and type of occupation (medical doctor, nurse, obstetric nurse, other).

Results

A total of 347 HCWs were enrolled in the study. The 57.3% reported to have missed diphtheritis-tetanus-pertussis (DTP) vaccination, the 50.1% reported to have missed measles-mumps-rubella (MPR) vaccination, and the 62.5% reported to have missed flu vaccination. In comparison with medical doctors, obstetric nurses were more likely to be associated to MPR vaccination (OR 2.8;95%CI 1.1-7.6; p = 0.047). As far as flu vaccination was concerned, both nurses and obstetric nurses showed lower confidence (respectively OR 0.2; 95%CI 0.1-0.3; p &lt; 0.001 and OR 0.1; 95%CI 0.1-0.5; p = 0.003). Moreover, other healthcare professionals reported to believe in natural immunization more than in vaccination (26.5%; p &lt; 0.001) and they were also worried about long-term effects of vaccination (10.2%; p = 0.044). Differently, nurses were more frequently worried about vaccine side effects (24%; p &lt; 0.001).

Conclusions

This survey shows that the vaccination coverage taken into consideration results to be below the 95% threshold. Training on vaccine and mandatory measures may be necessary in order to achieve better coverage.

Key messages

Among HCW all vaccination coverage considered resulted below the threshold. Training on vaccine and mandatory measures may be needed in order to achieve better coverage.

Heart failure hospitalizations in persons with and without diabetes in an Italian region: 2008-2018

Background

Hospitalization rate for heart failure (HF) is considered a prevention quality indicator and it is used as a tool to evaluate health services quality. This study aims to assess time trends in HF hospitalizations in a region of Southern Italy, focusing on diabetes mellitus as comorbidity.

Methods

Data were collected from hospital discharge records. All patients aged 18 or over hospitalized for HF in Abruzzo between 2008 and 2018 were selected, either with or without a diagnostic code of diabetes. Admissions for cardiac procedures were excluded. For each year, gender- and age-adjusted standardized hospitalization rates were calculated. Predictors of HF admissions were estimated by a multivariable regression model.

Results

Over the study period, 60,737 HF admissions occurred, 34,518 of which among people aged more than 65 (56.8%). A total of 15,424 hospitalizations were performed among diabetic patients (25.4%). The overall age- and gender-adjusted HF hospitalization rate declined substantially from 2008 to 2018 (-12.1%). Diabetes (adjOR 2.48; 95%CI 2.41-2.55), myocardial infarction (adjOR 3.92; 95%CI 3.70-4.14), peripheral vascular disease (adjOR 2.30; 95%CI 2.16-2.44), chronic obstructive pulmonary disease (adjOR 3.97; 95%CI 3.86-4.09) and renal disease (adjOR 5.61; 95%CI 5.44-5.78) were factors associated to an increased risk of HF hospitalization. Although HF admission rates remained higher, a significant reduction was highlighted among diabetic patients (-34.7%). Instead, time trend was nearly stable among persons without diabetes (+2.7%).

Conclusions

This study has shown a decline in HF hospitalization rate over the period considered, particularly among diabetic patients. HF hospitalization may be potentially avoided with good outpatient care. As the causes for HF admissions may include poor quality of care or problems accessing care, it is worthwhile to identify the triggering factors and the potential targets for an early intervention.

Key messages

A reduction of HF admissions was observed only among diabetics and not among people without diabetes. As the HF hospitalizations are potentially preventable, the knowledge of the epidemiology is crucial for management of preventive health care.

Infections in diabetics: a ten-year analysis on hospital discharge records in an Italian region

Background

Patients with diabetes mellitus (DM) have increased risk of developing infections and complications from infections that require hospitalization and greater healthcare utilization. This study aimed to analyze hospitalizations in DM patients with a diagnosis of infection and to assess the burden of infections on the regional healthcare system in terms of length of stay and in-hospital mortality.

Methods

A retrospective cross-sectional study was performed from 2006 to 2015 in Abruzzo, an Italian region. Data were collected from hospital discharge records (HDRs) of patients with a diagnosis of DM. All the admissions with an ICD-9 infection diagnostic code were identified. Logistic regression models were implemented to evaluate the association between infections and the study outcomes.

Results

A total of 182,709 HDRs of DM patients were identified, 12,381 (6.78%) of which related to an infectious disease. The number of admissions with a diagnosis of infection increased during the study period (+4.0%). Respiratory infections were the most common (69.8%), followed by sepsis (9%), and skin and soft tissue infections (8.7%). Factors associated with the infection were age&lt;18 (aOR=1.88; 95%CI:1.42-2.47), age≥65 (aOR=1.29; 95%CI:1.23-1.35), and DM type 2 (aOR=1.19; 95%CI:1.12-1.26). Diabetic patients with an infectious disease had a longer median length of stay (days:10; IQR:6-16) than those without infections (days:7; IQR:3-12) (p &lt; 0.001), and showed higher in-hospital mortality (aOR=2.67; 95% CI:2.5-2.8).

Conclusions

Over the study period, hospitalizations related to infections among diabetics rose. The increase was registered mostly among the youngest and the oldest subjects. Infectious disease diagnosis was associated with longer length of stay and higher in-hospital mortality. Cost-effective strategies for infection prevention in patients with DM are needed in order to reduce morbidity and the impact of these conditions on the healthcare system.

Key messages

Patients with diabetes have increased risk of developing infections. In our study, infectious disease diagnosis was associated with longer length of stay and higher in-hospital mortality. Cost-effective strategies for infection prevention in patients with diabetes are needed in order to reduce morbidity and the impact of these conditions on the healthcare system.

The effect of COPD on length of stay and in-hospital mortality of diabetic patients

Background

Chronic Obstructive Pulmonary Disease (COPD) is a preventable and treatable disease characterized by persistent respiratory symptoms and airflow limitation. It is currently one of the leading cause of death worldwide. Metabolic syndrome has been recognized as one of the most relevant clinical comorbidities associated with COPD. Diabetes is more prevalent in COPD than in the general population, ranging between 10.1-23.0%. However, the link between COPD and diabetes is much less clear. The aim of this study was to investigate the effect of COPD on diabetic patients, focusing on length of stay and in-hospital mortality.

Methods

The study considered all hospital admissions of diabetic patients aged over 65 years performed between January 2006 and December 2015 in Abruzzo, a region of Italy. Data were collected from all hospital discharge records. A 1:1 propensity score-matching algorithm was used to match patients with and without COPD, according to their baseline characteristics. Logistic regression analysis was performed to evaluate the risk of in-hospital mortality and prolonged length of stay among diabetic patients with COPD.

Results

A total of 140,556 ?patients were included: 18,379 with COPD and 122,177 without COPD. After matching procedure, 36,758 patients were included into the analysis: 18,379 with COPD and 18,379 controls. After matching, all the baseline characteristics resulted well balanced, with a standardized mean difference less than 10% for all the variables considered. COPD patients showed a higher risk of in-hospital mortality (OR: 1.10; 95%CI 1.01-1.20; p = 0.036) and length of stay over 15 days (OR:1.18; 95%CI 1.06-1.31; p = 0.002).

Conclusions

In a cohort of Italian patients, diabetic patients with COPD showed a higher risk of in-hospital mortality and prolonged length of stay compared with diabetic patients without COPD. Defining the causes of these differences would improve public health surveillance systems and policies.

Key messages

Diabetes is more prevalent in COPD than in the general population. Diabetic patients with COPD showed a higher risk of in-hospital mortality and prolonged length of stay compared with diabetic patients without COPD.

Arsenic Exposure and Risk of Urothelial Cancer: Systematic Review and Meta-Analysis

Background: Arsenic is a toxic metalloid element widely distributed throughout the environment. Arsenic contaminated water has become an ongoing public health issue affecting hundred million people worldwide. The aim of this paper was to summarize the evidence in the association between arsenic metabolites and urinary tract cancer risk. Methods: A systematic review was conducted searching for observational studies that evaluated the association of arsenic metabolites and urinary tract cancer. Risk estimates from individual studies were pooled by using random effects models. Results: All the metabolites considered in this study resulted to be significantly associated to urothelial cancer, respectively: IA% 3.51 (1.21-5.82) (p = 0.003), MMA with WMD = 2.77 (1.67-3.87) (p < 0.001) and DMA with WMD = -4.56 (-7.91-1.22) (p = 0.008). Conclusions: Arsenic metabolites are significantly associated to urothelial cancer. Future studies will help to verify the independent association(s) between arsenic metabolites and urothelial cancer.

Predictors and Trend of Ketoacidosis Hospitalization Rate in Type 2 Diabetes Mellitus Patients from 2006 to 2015 in Abruzzo Region, Italy

AIMS

This study aimed to assess the trend of hospitalizations for DKA in adult patients with type 2 diabetes mellitus and its associated factors.

DESIGN

A retrospective cross-sectional study was performed. Data were collected from hospital discharge records (HDRs) of patients (age ≥18) with either primary or secondary discharge diagnosis for DKA and type 2 diabetes from 2006 to 2015 in Abruzzo region. Age-adjusted hospitalization rates were computed by gender and standardized on the regional population in 2006. A logistic regression model was implemented using presence of DKA as dependent variable.

RESULTS

We identified 160,366 HDRs with type 2 diabetes. Out of them, 1611 (1.00%) were due to DKA. The hospitalization rates for DKA increased both for male +115.9 and female +142.8%, from 2006 to 2015. The most significant predictors of DKA were age 18-44 (aOR=4.17), uncontrolled diabetes (aOR=1.79), trauma (aOR=1.38), any infection (aOR=1.68), liver disease (aOR=1.29), fluid and electrolyte disorders (aOR=2.09), psychosis (aOR=1.69).

CONCLUSIONS

Trends of DKA in adult patients with type 2 diabetes has been increasing in both male and female. Multimorbidity is an open challenge for public health, therefore better coordination is needed among different specialist consultants to reduce the occurrence of this preventable complication.

Ketoacidosis admission rate in type 2 diabetes mellitus patients from 2006 to 2015 in Abruzzo, Italy

Background

Diabetic ketoacidosis (DKA) is a potentially life-threatening but largely preventable complication of diabetes and is associated with significant health care utilization and expenditure. Whereas DKA is mostly related to type 1 diabetes, over recent years an increasing number of hospital admissions for DKA have been reported in adult subjects with type 2 diabetes. The aim of this study was to assess the trend of hospitalizations for DKA in adult patients with type 2 diabetes and its associated factors.

Methods

A retrospective cross-sectional study was performed from 2006 to 2015 in Abruzzo region. Data were collected from hospital discharge records (HDRs) of type 2 diabetes adult patients with either primary or secondary diagnosis for DKA. Age-adjusted hospitalization rates were computed by gender and standardized on the regional population in 2006. A logistic regression model was implemented using the presence of DKA as dependent variable.

Results

We identified 160,366 HDRs with type 2 diabetes. Out of them, 1611 (1.00%) were due to DKA. The hospitalization rates for DKA increased both for male +115.9 and female +142.8%, from 2006 to 2015. Associated factors of DKA were age ranging from 18 to 44 (adjOR=4.17; 95%CI:3.27-4.31), uncontrolled diabetes (adjOR=1.79; 95%CI:1.60-2.01), trauma (adjOR=1.38; 95%CI:1.13-1.68), any infection (adjOR=1.68; 95%CI:1.22-.2.33), liver disease (adjOR=1.29; 95%CI:1.09-1.53), fluid and electrolyte disorders (adjOR=2.09; 95%CI:1.09-1.53), psychosis (adjOR=1.69; 95%CI:1.25-2.30).

Conclusions

Hospitalization trends for DKA in adult patients with type 2 diabetes have been increasing and are associated with some comorbidities. Early screening, appropriate patients, families and communities education remain an important aspect of preventing an acute diabetic complication such as DKA. Moreover, multimorbidity complicates the disease management and remains an open challenge for public health.

Key messages

This study addresses hospitalizations for DKA in adult patients with type 2 diabetes, an occurrence increasing worldwide for unclear reasons. For preventing DKA in type 2 diabetes patients, it is useful taking into consideration the known trigger factors, but it is also worthwhile improving the management of comorbidities in outpatients.

Arsenic metabolism and urothelial cancer risk: a systematic review and meta-analysis

Background

Arsenic is a toxic metalloid element frequently found in the environment. Chronic arsenic exposure is a critical public health issue in many countries since the identification of arsenic and its compounds as human carcinogens by the World Health Organization. After absorption, inorganic arsenic (iAs) is mainly methylated into monomethylated and dimethylated compounds (MMA, DMA), which are then excreted through the kidney together with unmethylated iAs. Whether the methylation process is to detoxify or potentiate arsenic toxicity, however, remains an ongoing debate. The purpose of this systematic review was to conduct a comprehensive meta-analysis to estimate the association between arsenic exposure and urothelial cancer.

Methods

10 observational studies met the inclusion criteria and were included in the systematic review. IAs%, MMA% and DMA% were extracted from each paper. Weighted Mean Differences with 95% confidence intervals were defined according to Cases minus Controls. Pooled risk estimates from individual studies were assessed using random effects models. Meta-regression analysis was performed to estimate the extent of urothelial cancer risk as a function of iAs%, MMA% and DMA%.

Results

Results showed as patients with urothelial cancer presented higher level of urinary iAs% (WMD 2.70, 95%CI 0.64-4.76), MMA% (WMD 2.81, 95%CI 1.43-4.20) and DMA% (WMD-3.44, 95%CI-6.57–0.30).

Conclusions

These findings suggest that higher level of iAs% and MMA% and lower level of DMA% were associated with an increased risk of urothelial cancer. Additional population based studies are needed to understand the role of arsenic in cancer development. Understanding the meaning of arsenic metabolism could improve the risk assessment of arsenic toxicity and provide a potential tool for disease prediction and prevention.

Key messages

Higher level of iAs%, MMA% and DMA% were associated with an increased risk of urothelial cancer. Understanding the meaning of arsenic metabolism could improve the risk assessment of arsenic toxicity.

Trends by gender and predictors of diabetes-related amputations: an Italian regional analysis

Background

Lower extremity amputations (LEAs) are common among people with diabetes, resulting in high disability and mortality. Understanding trends in diabetes-related LEAs is important for assessing the quality of care. Aim of this study was to evaluate predictors and time trends in LEAs in a region of Southern Italy, focusing on gender difference.

Methods

Hospital discharge records were used to identify all diabetic adult patients hospitalized for LEAs between 2006 and 2015. For each year, gender- and age-adjusted standardized hospitalization rates for major and minor amputations were calculated and time trends were analyzed by gender. Predictors of LEAs were estimated by a multivariable regression model.

Results

In the study period, 579 major and 1345 minor amputations were performed in Abruzzo. Gender- and age-adjusted standardized admission rates decreased for minor amputations among both males (-29.96%) and females (-5.33%), whereas major amputations rates decreased only for males (-44.73%). Males were at higher risk of undergoing major (Rate Ratio [RR] 1.41, 95%CI 1.19-1.67) and minor (RR 1.62, 95%CI 1.45-1.82) amputations, but the male-to-female rate ratio decreased for major and minor amputations. Peripheral vascular disease was the main predictor of major (adjOR 4.09, 95%CI 3.31-5.06) and minor amputations (adjOR 12.90, 95%CI 11.00-15.12). Age over 85 (adjOR 9.07, 95%CI 1.84-44.71) and more than 3 comorbidities (adjOR 2.51, 95%CI 1.75-3.60) were parameters associated only with major amputations.

Conclusions

Reducing the number of LEAs represents a healthcare priority. This study emphasizes the existence of gender disparities in LEAs, highlighting a significant reduction of LEAs for males and a lack of improvement for females. Thus, it is worthwhile to investigate potential clinical, behavioral and healthcare-related causes of this difference, in order to plan health system changes aimed at improving care and facilitating access to health care for women.

Key messages

Time trends in LEAs showed a substantial improvement only for males, highlighting the existence of gender difference. Understanding the underlying causes is essential to improve the quality of care.

Trends of diabetes-delated preventable hospitalizations in an italian region from 2006 to 2015

Background

Diabetes-related preventable hospitalizations (DRPHs) are indicators of primary care effective services. The aim of this study is to compute the trends of DRPHs, and to assess the risk factors for increased in-hospital length of stay (LOS) and costs in an Italian region.

Methods

DRPHs were computed following the AHRQ definitions, which include four types: short-term complications (PQI-1), long-term complications (PQI-3), uncontrolled diabetes (PQI-14), lower-extremity amputations (PQI-16). Trends were direct standardized on in-habitants in 2006. Negative binomial regression model was used.

Results

In the study period PQI-1 increased +426.9 %, PQI-3 +175.5%, PQI-14 +231.7% and PQI-16 decreased -26.2%. Prolonged LOS was related to type 2 diabetes (p &lt; 0.001), peripheral vascular disease (p = 0.045), uncomplicated hypertension (p &lt; 0.001), liver disease (p &lt; 0.001) for PQI-1; type 2 diabetes (p &lt; 0.001), uncomplicated hypertension (p &lt; 0.001), complicated hypertension (p &lt; 0.001) for PQI-3; type 2 diabetes (p &lt; 0.001 ), complicated hypertension (p = 0.001), metastasis (p = 0.042) for PQI-14; female gender (p = 0.001), congestive heart failure (CHF) (p = 0.001), valvulopathy (p = 0.024), BPCO (p = 0.028), renal failure (p &lt; 0.001), liver disease (p = 0.015) for PQI-16.Considerable factors affecting the costs were female gender (p = 0.005), peripheral vascular disease (p = 0.006), renal failure (p = 0.050) for PQI-1; type 2 diabetes (p = 0.002), arrhythmia (p = 0.002), peripheral vascular disease (p &lt; 0.001), BPCO (p &lt; 0.001), renal failure (p &lt; 0.001) for PQI-3; peripheral vascular disease (p = 0.004), uncomplicated hypertension (p = 0.005), BPCO (p = 0.011), renal failure (p = 0.009), liver disease (p &lt; 0.001), psychosis (p = 0.027) for PQI-14; CHF (p = 0.014), arrhythmia (p = 0.001 ), uncomplicated hypertension (p = 0.003), renal failure (p = 0.008), deficiency anemia (p = 0.032) for PQI-16.

Conclusions

DRPHs has been increasing and some comorbidities need to be better managed in outpatient setting to reduce LOS and costs.

Key messages

This study addresses the effect of multimorbidity on the burden of diabetes-related preventable hospitalizations using administrative data from an entire italian region over 10 years period. This study uses Prevention Quality Indicators to measure their burden on regional public health and produces useful evidences for the improvement of diabetes management in outpatient setting.

Bedrock sculpting under an active alpine glacier revealed from cosmic-ray muon radiography

Mountain glaciers form landscapes with U-shaped valleys, roche moutonées and overdeepenings through bedrock erosion. However, little evidence for active glacial carving has been provided particularly for areas above the Equilibrium Line Altitude (ELA) where glaciers originate. This is mainly due to our lack of information about the shape of the bedrock underneath active glaciers in highly elevated areas. In the past years, the bedrock morphology underneath active glaciers has been studied by geophysical methods in order to infer the subglacial mechanisms of bedrock erosion. However, these comprise surveys on the glaciers' surface, from where it has been difficult to investigate the lateral boundary between the ice and the bedrock with sufficient resolution. Here we perform a muon-radiographic inspection of the Eiger glacier (Switzerland, European Alps) with the aid of cosmic-ray muon attenuation. We find a reach (600 × 300 m) within the accumulation area where strong lateral glacial erosion has cut nearly vertically into the underlying bedrock. This suggests that the Eiger glacier has profoundly sculpted its bedrock in its accumulation area. This also reveals that the cosmic-ray muon radiography is an ideal technology to reconstruct the shape of the bedrock underneath an active glacier.

First demonstration of antimatter wave interferometry

Interference of matter waves is at the heart of quantum physics and has been observed for a wide range of particles from electrons to complex molecules. Here, we demonstrate matter wave interference of single positrons using a period-magnifying Talbot-Lau interferometer based on material diffraction gratings. The system produced high-contrast periodic fringes, which were detected by means of nuclear emulsions capable of determining the impact point of each individual positron with submicrometric resolution. The measured energy dependence of fringe contrast in the range of 8 to 16 keV proves the quantum-mechanical origin of the periodic pattern and excludes classical projective effects, providing the first observation to date of antimatter wave interference. Future applications of this interferometric technique include the measurement of the gravitational acceleration of neutral antimatter systems exploiting the inertial sensing capabilities of Talbot-Lau interference.

Study of the radioactivity induced in air by a 15-MeV proton beam

Radioactivity induced by a 15-MeV proton beam extracted into air was studied at the beam transport line of the 18-MeV cyclotron at the Bern University Hospital (Inselspital). The produced radioactivity was calculated and measured by means of proportional counters located at the main exhaust of the laboratory. These devices were designed for precise assessment of air contamination for radiation protection purposes. The main produced isotopes were (11)C, (13)N and (14)O. Both measurements and calculations correspond to two different irradiation conditions. In the former, protons were allowed to travel for their full range in air. In the latter, they were stopped at the distance of 1.5 m by a beam dump. Radioactivity was measured continuously in the exhausted air starting from 2 min after the end of irradiation. For this reason, the short-lived (14)O isotope gave a negligible contribution to the measured activity. Good agreement was found between the measurements and the calculations within the estimated uncertainties. Currents in the range of 120-370 nA were extracted in air for 10-30 s producing activities of 9-22 MBq of (11)C and (13)N. The total activities for (11)C and (13)N per beam current and irradiation time for the former and the latter irradiation conditions were measured to be (3.60 ± 0.48) × 10(-3) MBq (nA s)(-1) and (2.89 ± 0.37) × 10(-3) MBq (nA s)(-1), respectively.

Accelerator-based tests of radiation shielding properties of materials used in human space infrastructures

Shielding is the only practical countermeasure for the exposure to cosmic radiation during space travel. It is well known that light, hydrogenated materials, such as water and polyethylene, provide the best shielding against space radiation. Kevlar and Nextel are two materials of great interest for spacecraft shielding because of their known ability to protect human space infrastructures from meteoroids and debris. We measured the response to simulated heavy-ion cosmic radiation of these shielding materials and compared it to polyethylene, Lucite (PMMA), and aluminum. As proxy to galactic nuclei we used 1 GeV n iron or titanium ions. Both physics and biology tests were performed. The results show that Kevlar, which is rich in carbon atoms (about 50% in number), is an excellent space radiation shielding material. Physics tests show that its effectiveness is close (80-90%) to that of polyethylene, and biology data suggest that it can reduce the chromosomal damage more efficiently than PMMA. Nextel is less efficient as a radiation shield, and the expected reduction on dose is roughly half that provided by the same mass of polyethylene. Both Kevlar and Nextel are more effective than aluminum in the attenuation of heavy-ion dose.

Shielding of relativistic protons

Protons are the most abundant element in the galactic cosmic radiation, and the energy spectrum peaks around 1 GeV. Shielding of relativistic protons is therefore a key problem in the radiation protection strategy of crewmembers involved in long-term missions in deep space. Hydrogen ions were accelerated up to 1 GeV at the NASA Space Radiation Laboratory, Brookhaven National Laboratory, New York. The proton beam was also shielded with thick (about 20 g/cm2) blocks of lucite (PMMA) or aluminium (Al). We found that the dose rate was increased 40-60% by the shielding and decreased as a function of the distance along the axis. Simulations using the General-Purpose Particle and Heavy-Ion Transport code System (PHITS) show that the dose increase is mostly caused by secondary protons emitted by the target. The modified radiation field after the shield has been characterized for its biological effectiveness by measuring chromosomal aberrations in human peripheral blood lymphocytes exposed just behind the shield block, or to the direct beam, in the dose range 0.5-3 Gy. Notwithstanding the increased dose per incident proton, the fraction of aberrant cells at the same dose in the sample position was not significantly modified by the shield. The PHITS code simulations show that, albeit secondary protons are slower than incident nuclei, the LET spectrum is still contained in the low-LET range (<10 keV/microm), which explains the approximately unitary value measured for the relative biological effectiveness.

Cytogenetic effects of high-energy iron ions: dependence on shielding thickness and material

We report results for chromosomal aberrations in human peripheral blood lymphocytes after they were exposed to high-energy iron ions with or without shielding at the HIMAC, AGS and NSRL accelerators. Isolated lymphocytes were exposed to iron ions with energies between 200 and 5000 MeV/nucleon in the 0.1-1-Gy dose range. Shielding materials consisted of polyethylene, lucite (PMMA), carbon, aluminum and lead, with mass thickness ranging from 2 to 30 g/cm2. After exposure, lymphocytes were stimulated to grow in vitro, and chromosomes were prematurely condensed using a phosphatase inhibitor (calyculin A). Aberrations were scored using FISH painting. The yield of total interchromosomal exchanges (including dicentrics, translocations and complex rearrangements) increased linearly with dose or fluence in the range studied. Shielding decreased the effectiveness per unit dose of iron ions. The highest RBE value was measured with the 1 GeV/nucleon iron-ion beam at NSRL. However, the RBE for the induction of aberrations apparently is not well correlated with the mean LET. When shielding thickness was increased, the frequency of aberrations per particle incident on the shield increased for the 500 MeV/nucleon ions and decreased for the 1 GeV/nucleon ions. Maximum variation at equal mass thickness was obtained with light materials (polyethylene, carbon or PMMA). Variations in the yield of chromosomal aberrations per iron particle incident on the shield follow variations in the dose per incident particle behind the shield but can be modified by the different RBE of the mixed radiation field produced by nuclear fragmentation. The results suggest that shielding design models should be benchmarked using both physics and biological data.

Modelled microgravity does not modify the yield of chromosome aberrations induced by high-energy protons in human lymphocytes

The aim was to evaluate the effect of modelled microgravity on radiation-induced chromosome aberrations (CAs). G0 peripheral blood lymphocytes were exposed to 60 MeV protons or 250 kVp X-rays in the dose range 0-6 Gy, and allowed to repair DNA damage for 24 h under either normal gravity or microgravity modelled by the NASA-designed rotating-wall bioreactor. Cells were then stimulated to proliferate by phytohaemagglutinin (PHA) under normal gravity conditions and prematurely condensed chromosomes were harvested after 48 h. CAs were scored in chromosomes 1 and 2 by fluorescence in-situ hybridization. Proliferation gravisensitivity was examined by cell growth curves and by morphological evaluation of mitogen-induced activation. Cell replication rounds were monitored by bromodeoxyuridine labelling. Modelled microgravity markedly reduced PHA-mediated lymphocyte blastogenesis and cell growth. However, no significant differences between normal gravity and modelled microgravity were found in the dose-response curves for the induction of aberrant cells or total interchromosomal exchange frequency. Rotating-wall bioreactor-based microgravity reproduced space-related alterations of mitogen stimulation in human lymphocytes but did not affect the yield of CAs induced by low-linear energy transfer radiation.

Fragmentation studies of relativistic iron ions using plastic nuclear track detectors

We measured fluence and fragmentation of high-energy (1 or 5 A GeV) 56Fe ions accelerated at the Alternating Gradient Synchrotron or at the NASA Space Radiation Laboratory (Brookhaven National Laboratory, NY, USA) using solid-state CR-39 nuclear track detectors. Different targets (polyethylene, PMMA, C, Al, Pb) were used to produce a large spectrum of charged fragments. CR-39 plastics were exposed both in front and behind the shielding block (thickness ranging from 5 to 30 g/cm2) at a normal incidence and low fluence. The radiation dose deposited by surviving Fe ions and charged fragments was measured behind the shield using an ionization chamber. The distribution of the measured track size was exploited to distinguish the primary 56Fe ions tracks from the lighter fragments. Measurements of projectile's fluence in front of the shield were used to determine the dose per incident particle behind the block. Simultaneous measurements of primary 56Fe ion tracks in front and behind the shield were used to evaluate the fraction of surviving iron projectiles and the total charge-changing fragmentation cross-section. These physical measurements will be used to characterize the beam used in parallel biological experiments.

Chromosomal aberrations induced by high-energy iron ions with shielding

Biophysical models are commonly used to evaluate the effectiveness of shielding in reducing the biological damage caused by cosmic radiation in space flights. To improve and validate these codes biophysical experiments are needed. We have measured the induction of chromosomal aberrations in human peripheral blood lymphocytes exposed in vitro to 500 MeV/n iron ion beams (dose range 0.1-1 Gy) after traversing shields of different material (lucite, aluminium, or lead) and thickness (0-11.3 g/cm2). For comparison, cells were exposed to 200 MeV/n iron ions and to X-rays. Chromosomes were prematurely condensed by a phosphatase inhibitor (calyculin A) to avoid cell-cycle selection produced by the exposure to high-LET heavy-ion beams. Aberrations were scored in chromosomes 1, 2, and 4 following fluorescence in situ hybridization. The fraction of aberrant lymphocytes has been evaluated as a function of the dose at the sample position, and of the fluence of primary 56Fe ions hitting the shield. The influence of shield thickness on the action cross-section for the induction of exchange-type aberrations has been analyzed, and the dose average-LET measured as a function of the shield thickness. These preliminary results prove that the effectiveness of heavy ions is modified by shielding, and the biological damage is dependent upon shield thickness and material.

Biological dosimetry in Russian and Italian astronauts

Large uncertainties are associated with estimates of equivalent dose and cancer risk for crews of long-term space missions. Biological dosimetry in astronauts is emerging as a useful technique to compare predictions based on quality factors and risk coefficients with actual measurements of biological damage in-flight. In the present study, chromosomal aberrations were analyzed in one Italian and eight Russian cosmonauts following missions of different duration on the MIR and the international space station (ISS). We used the technique of fluorescence in situ hybridization (FISH) to visualize translocations in chromosomes 1 and 2. In some cases, an increase in chromosome damage was observed after flight, but no correlation could be found between chromosome damage and flight history, in terms of number of flights at the time of sampling, duration in space and extra-vehicular activity. Blood samples from one of the cosmonauts were exposed in vitro to 6 MeV X-rays both before and after the flight. An enhancement in radiosensitivity induced by the spaceflight was observed.

Cell inactivation by beryllium, boron and carbon ions at the low-energy irradiation facility of the Naples University

The 3MV HVEC TTT-3 Tandem accelerator at the University of Naples, already used for radiobiological studies with protons and alpha particles, was set up for irradiation of biological samples with low energy carbon, boron, and beryllium beams. Radiobiological characterisation and study of these ion beams is essential in hadrontherapy (correction of hadrotherapy) to understand, for example, the possible biological effect of the target fragmentation products. Furthermore in space radiation biology we need to know the biological effects of heavy ions, a component of cosmic radiation that can contribute to the radiobiological risk when long sojourns in space are concerned. V79 Chinese hamster cells were irradiated with the different ions and the resulting cell inactivation data are reported.

A model of radiation-induced myelopoiesis in space

Astronauts' radiation exposure limits are based on experimental and epidemiological data obtained on Earth. It is assumed that radiation sensitivity remains the same in the extraterrestrial space. However, human radiosensitivity is dependent upon the response of the hematopoietic tissue to the radiation insult. It is well known that the immune system is affected by microgravity. We have developed a mathematical model of radiation-induced myelopoiesis which includes the effect of microgravity on bone marrow kinetics. It is assumed that cellular radiosensitivity is not modified by the space environment, but repopulation rates of stem and stromal cells are reduced as a function of time in weightlessness. A realistic model of the space radiation environment, including the HZE component, is used to simulate the radiation damage. A dedicated computer code was written and applied to solar particle events and to the mission to Mars. The results suggest that altered myelopoiesis and lymphopoiesis in microgravity might increase human radiosensitivity in space.

Effect of space radiation on expression of apoptosis-related genes in endometrial cells: a preliminary study

In this paper we present some preliminary results on alteration of gene expression caused by radiation on human endometrial cells. To this purpose, we have studied the modulation of the expression of the bcl-2 gene family in two cell lines following irradiations with low energy protons and gamma-rays from a 60Co. The two epithelial cell strains, namely AN3Ca and HEC1B cells, both obtained from human neoplastic endometrial tissues, grow in culture and continue to maintain some differentiated functions typical of the original tissue. Indeed, these cells, that can be considered as representative of different stages of cellular transformation of endometrium. Because their epithelial nature and rapid growth, the expression of genes related to the maintenance of the cellular homeostasis (correction of omeostasis), as the pro and anti-apoptotic ones, is expected to be susceptible to changes in environment, including radiation. The effects have been evaluated in terms of both cell survival and changes in the expression of pro- and anti apoptotic proteins. Even though the data reported above can not be considered complete and/or definitive, nevertheless, in whole, they confirm that these cells may constitute a suitable model system to study, at molecular level, the effects of cosmic radiation on endometrium. Further observation, ensuing from these preliminary data, is that endometrial cells present different sensitivity to radiation in regard to its 'quality' and 'dosage', in accord to the original stage of differentiation.

Inactivation of human cells exposed to fractionated doses of low energy protons: relationship between cell sensitivity and recovery efficiency

Within the framework of radiation biophysics research in the hadrontherapy field, split-dose studies have been performed on four human cell lines with different radiation sensitivity (SCC25, HF19, H184B5 F5-1 M10, and SQ20B). Low energy protons of about 8 and 20 keV/micron LET and gamma-rays were used to study the relationship between the recovery ratio and the radiation quality. Each cell line was irradiated with two dose values corresponding to survival levels of about 5% and 1%. The same total dose was also delivered in two equal fractions separated by 1.5, 3, and 4.5 hours. A higher maximum recovery ratio was observed for radiosensitive cell lines as compared to radioresistant cells. The recovery potential after split doses was small for slow protons, compared to low-LET radiation. These data show that radiosensitivity may not be related to a deficient recovery, and suggest a possible involvement of inducible repair mechanisms.

On the radiosensitivity of man in space

Astronauts' radiation exposure limits are based on experimental and epidemiological data obtained on Earth. It is assumed that radiation sensitivity remains the same in the extraterrestrial space. However, human radiosensitivity is dependent upon the response of the hematopoietic tissue to the radiation insult. It is well known that the immune system is affected by microgravity. We have developed a mathematical model of radiation-induced myelopoiesis which includes the effect of microgravity on bone marrow kinetics. It is assumed that cellular radiosensitivity is not modified by the space environment, but repopulation rates of stem and stromal cells are reduced as a function of time in weightlessness. A realistic model of the space radiation environment, including the HZE component, is used to simulate the radiation damage. A dedicated computer code was written and applied to solar particle events and to the mission to Mars. The results suggest that altered myelopoiesis and lymphopoiesis in microgravity might increase human radiosensitivity in space.

Calibration curves for biological dosimetry by fluorescence in situ hybridisation

Dose-response curves were measured for the induction of chromosomal aberrations in peripheral blood lymphocytes after acute exposure in vitro to 60Co gamma rays. Blood was obtained from four different healthy donors, and chromosomes were either observed at metaphase, following colcemid accumulation, or prematurely condensed by calyculin A. Cells were analysed in three different Italian laboratories. Chromosomes 1, 2, and 4 were painted, and simple-type interchanges between painted and non-painted chromosomes were scored in cells exposed in the dose range 0.1-3.0 Gy. The chemical-induced premature chromosome condensation method was also used combined with chromosome painting (chromosome 4 only) to determine calibration curves for high dose exposures (up to 20 Gy X rays). Calibration curves described in this paper will be used in our laboratories for biological dosimetry by fluorescence in situ hybridisation.