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1.
Environ Int ; 160: 107069, 2022 02.
Article in English | MEDLINE | ID: mdl-34974237

ABSTRACT

In recent decades, the possibility that use of mobile communicating devices, particularly wireless (mobile and cordless) phones, may increase brain tumour risk, has been a concern, particularly given the considerable increase in their use by young people. MOBI-Kids, a 14-country (Australia, Austria, Canada, France, Germany, Greece, India, Israel, Italy, Japan, Korea, the Netherlands, New Zealand, Spain) case-control study, was conducted to evaluate whether wireless phone use (and particularly resulting exposure to radiofrequency (RF) and extremely low frequency (ELF) electromagnetic fields (EMF)) increases risk of brain tumours in young people. Between 2010 and 2015, the study recruited 899 people with brain tumours aged 10 to 24 years old and 1,910 controls (operated for appendicitis) matched to the cases on date of diagnosis, study region and age. Participation rates were 72% for cases and 54% for controls. The mean ages of cases and controls were 16.5 and 16.6 years, respectively; 57% were males. The vast majority of study participants were wireless phones users, even in the youngest age group, and the study included substantial numbers of long-term (over 10 years) users: 22% overall, 51% in the 20-24-year-olds. Most tumours were of the neuroepithelial type (NBT; n = 671), mainly glioma. The odds ratios (OR) of NBT appeared to decrease with increasing time since start of use of wireless phones, cumulative number of calls and cumulative call time, particularly in the 15-19 years old age group. A decreasing trend in ORs was also observed with increasing estimated cumulative RF specific energy and ELF induced current density at the location of the tumour. Further analyses suggest that the large number of ORs below 1 in this study is unlikely to represent an unknown causal preventive effect of mobile phone exposure: they can be at least partially explained by differential recall by proxies and prodromal symptoms affecting phone use before diagnosis of the cases. We cannot rule out, however, residual confounding from sources we did not measure. Overall, our study provides no evidence of a causal association between wireless phone use and brain tumours in young people. However, the sources of bias summarised above prevent us from ruling out a small increased risk.


Subject(s)
Brain Neoplasms , Cell Phone , Glioma , Adolescent , Adult , Brain Neoplasms/epidemiology , Brain Neoplasms/etiology , Case-Control Studies , Child , Electromagnetic Fields/adverse effects , Glioma/etiology , Humans , Male , Radio Waves/adverse effects , Young Adult
2.
J Eur Acad Dermatol Venereol ; 36(3): 391-402, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34862986

ABSTRACT

BACKGROUND: Early diagnosis is the most effective intervention to improve the prognosis of cutaneous melanoma. Even though the introduction of dermoscopy has improved the diagnostic accuracy, it can still be difficult to distinguish some melanomas from benign melanocytic lesions. Digital dermoscopy monitoring can identify dynamic changes of melanocytic lesions: To date, some algorithms were proposed, but a universally accepted one is still lacking. OBJECTIVES: To identify independent predictive variables associated with the diagnosis of cutaneous melanoma and develop a multivariable dermoscopic prediction model able to discriminate benign from malignant melanocytic lesions undergoing digital dermoscopy monitoring. METHODS: We collected dermoscopic images of melanocytic lesions excised after dermoscopy monitoring and carried out static and dynamic evaluations of dermoscopic features. We built two multivariable predictive models based on logistic regression and random forest. RESULTS: We evaluated 173 lesions (65 cutaneous melanomas and 108 nevi). Forty-two melanomas were in situ, and the median thickness of invasive melanomas was 0.35 mm. The median follow-up time was 9.8 months for melanomas and 9.1 for nevi. The logistic regression and random forest models performed with AUC values of 0.87 and 0.89, respectively, were substantially higher than those of the static evaluation models (ABCD TDS score, 0.57; 7-point checklist, 0.59). Finally, we built two risk calculators, which translate the proposed models into user-friendly applications, to assist clinicians in the decision-making process. CONCLUSIONS: The present study demonstrates that the integration of dynamic and static evaluations of melanocytic lesions is a safe approach that can significantly boost the diagnostic accuracy for cutaneous melanoma. We propose two diagnostic tools that significantly increase the accuracy in discriminating melanoma from nevi during digital dermoscopy monitoring.


Subject(s)
Melanoma , Nevus , Skin Neoplasms , Dermoscopy/methods , Humans , Melanocytes/pathology , Melanoma/diagnostic imaging , Melanoma/pathology , Nevus/diagnostic imaging , Skin Neoplasms/diagnostic imaging , Skin Neoplasms/pathology
3.
ESMO Open ; 6(2): 100064, 2021 04.
Article in English | MEDLINE | ID: mdl-33711672

ABSTRACT

BACKGROUND: Checkpoint inhibitors in melanoma can lead to self-immune side-effects such as vitiligo-like depigmentation (VLD). Beyond the reported association with favorable prognosis, there are limited data regarding VLD patient features and their echo on the therapeutic outcomes. METHODS: To assess the association between VLD and a series of clinical and biological features as well as therapeutic outcomes, we built an observational cohort study by recruiting patients who developed VLD during checkpoint inhibitors. RESULTS: A total of 148 patients from 15 centers (101 men, median age 66 years, BRAF mutated 23%, M1c 42%, Eastern Cooperative Oncology Group (ECOG) status 0/1 99%, normal lactate dehydrogenase 74%) were enrolled. VLD was induced by ipilimumab, programmed cell death-1 (PD-1) inhibitors, and their combination in 32%, 56%, and 12%, respectively. The median onset was 26 weeks and it was associated with other skin and nonskin toxicities in 27% and 28%, respectively. After 3 years of VLD onset, 52% (95% confidence interval 39% to 63%) were progression free and 82% (95% confidence interval 70% to 89%) were still alive. The overall response rate was 73% with 26% complete response. Univariable analysis indicated that BRAF V600 mutation was associated with a better overall survival (P = 0.028), while in multivariable analysis a longer progression-free survival was associated with BRAF V600 (P = 0.093), female sex (P = 0.008), and M stage other than 1a (P = 0.024). When VLD occurred, there was a significant decrease of white blood cell (WBC) count (P = 0.05) and derived WBC-to-lymphocytes ratio (dWLR; P = 0.003). A lower monocyte count (P = 0.02) and dWLR (P = 0.01) were also reported in responder patients. CONCLUSIONS: Among VLD population, some features might help to identify patients with an effective response to immunotherapy, allowing clinicians to make more appropriate choices in terms of therapeutic options and duration.


Subject(s)
Immune Checkpoint Inhibitors/adverse effects , Ipilimumab/adverse effects , Melanoma , Vitiligo , Aged , Female , Humans , Immune Checkpoint Inhibitors/therapeutic use , Ipilimumab/therapeutic use , Italy/epidemiology , Male , Melanoma/drug therapy , Vitiligo/chemically induced , Vitiligo/diagnosis
4.
Br J Dermatol ; 184(4): 722-730, 2021 04.
Article in English | MEDLINE | ID: mdl-32479678

ABSTRACT

BACKGROUND: The PROspective Cutaneous Lymphoma International Prognostic Index (PROCLIPI) study is a prospective analysis of an international database. Here we examine front-line treatments and quality of life (QoL) in patients with newly diagnosed mycosis fungoides (MF). OBJECTIVES: To identify (i) differences in first-line approaches according to tumour-nodes-metastasis-blood (TNMB) staging; (ii) parameters related to a first-line systemic approach and (iii) response rates and QoL measures. METHODS: In total, 395 newly diagnosed patients with early-stage MF (stage IA-IIA) were recruited from 41 centres in 17 countries between 1 January 2015 and 31 December 2018 following central clinicopathological review. RESULTS: The most common first-line therapy was skin-directed therapy (SDT) (322 cases, 81·5%), while a smaller percentage (44 cases, 11·1%) received systemic therapy. Expectant observation was used in 7·3%. In univariate analysis, the use of systemic therapy was significantly associated with higher clinical stage (IA, 6%; IB, 14%; IIA, 20%; IA-IB vs. IIA, P < 0·001), presence of plaques (T1a/T2a, 5%; T1b/T2b, 17%; P < 0·001), higher modified Severity Weighted Assessment Tool (> 10, 15%; ≤ 10, 7%; P = 0·01) and folliculotropic MF (FMF) (24% vs. 12%, P = 0·001). Multivariate analysis demonstrated significant associations with the presence of plaques (T1b/T2b vs. T1a/T2a, odds ratio 3·07) and FMF (odds ratio 2·83). The overall response rate (ORR) to first-line SDT was 73%, while the ORR to first-line systemic treatments was lower (57%) (P = 0·027). Health-related QoL improved significantly both in patients with responsive disease and in those with stable disease. CONCLUSIONS: Disease characteristics such as presence of plaques and FMF influence physician treatment choices, and SDT was superior to systemic therapy even in patients with such disease characteristics. Consequently, future treatment guidelines for early-stage MF need to address these issues.


Subject(s)
Mycosis Fungoides , Skin Neoplasms , Humans , Mycosis Fungoides/pathology , Mycosis Fungoides/therapy , Neoplasm Staging , Prognosis , Prospective Studies , Quality of Life , Skin Neoplasms/pathology , Skin Neoplasms/therapy
5.
One Health ; 10: 100159, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33117874

ABSTRACT

INTRODUCTION: Historically, leishmaniasis in Italy was constrained to areas with Mediterranean climate. In the last 20 years, sand fly vectors (Phlebotomus perniciosus), cases of canine leishmaniasis (CanL) and cases of human visceral leishmaniasis (VL) have been observed in Northern Italian regions, traditionally classified as cold areas unsuitable for sand fly survival. AIM: We aim to evaluate through a One-Health approach the risk of endemic transmission of Leishmania infantum in the Piedmont Region, Northern Italy. METHODS: We collected environmental, entomological, animal, and human data. We applied a geostatistical binomial model to map the probability of P. perniciosus presence in the study area, using selected environmental parameters as predictors. We evaluated the spatial relationship between the probability of P. perniciosus presence and the geographical distribution of CanL and VL cases observed between 1999 and 2013. RESULTS: Between 1999 and 2003, 142 sampling sets (17%) out of 839 resulted positive for P. perniciosus. Elevation, degree of slope, normalized difference vegetation index (NDVI) and summer temperatures were associated with positive sampling sets. During the study period, 164 (13.6%) of Piedmont municipalities reported at least one autochthonous case of CanL, while 89 VL cases were observed in 54 municipalities (4.5%). We observed an association between municipalities affected by autochthonous CanL cases and the estimated probability of P. perniciosus presence (Odds Ratio for 10% increase of probability: 2.66; 95% confidence intervals (CI): 2.16-3.37). We found that human VL incident cases were positively associated with the probability of the municipality of residence of being endemic for CanL (Incidence Rate Ratio for 10% increase of probability: 1.49; 95% CI 1.02-2.16). CONCLUSIONS: Using a One-Health approach, we quantified the spatial association between the distribution of P. perniciosus, municipalities endemic for CanL and incident cases of human VL, suggesting that the disease has become endemic in the Piedmont region.

7.
Ann Oncol ; 28(10): 2517-2525, 2017 Oct 01.
Article in English | MEDLINE | ID: mdl-28961843

ABSTRACT

BACKGROUND: Advanced-stage mycosis fungoides (MF)/Sézary syndrome (SS) patients are weighted by an unfavorable prognosis and share an unmet clinical need of effective treatments. International guidelines are available detailing treatment options for the different stages but without recommending treatments in any particular order due to lack of comparative trials. The aims of this second CLIC study were to retrospectively analyze the pattern of care worldwide for advanced-stage MF/SS patients, the distribution of treatments according to geographical areas (USA versus non-USA), and whether the heterogeneity of approaches has potential impact on survival. PATIENTS AND METHODS: This study included 853 patients from 21 specialist centers (14 European, 4 USA, 1 each Australian, Brazilian, and Japanese). RESULTS: Heterogeneity of treatment approaches was found, with up to 24 different modalities or combinations used as first-line and 36% of patients receiving four or more treatments. Stage IIB disease was most frequently treated by total-skin-electron-beam radiotherapy, bexarotene and gemcitabine; erythrodermic and SS patients by extracorporeal photochemotherapy, and stage IVA2 by polychemotherapy. Significant differences were found between USA and non-USA centers, with bexarotene, photopheresis and histone deacetylase inhibitors most frequently prescribed for first-line treatment in USA while phototherapy, interferon, chlorambucil and gemcitabine in non-USA centers. These differences did not significantly impact on survival. However, when considering death and therapy change as competing risk events and the impact of first treatment line on both events, both monochemotherapy (SHR = 2.07) and polychemotherapy (SHR = 1.69) showed elevated relative risks. CONCLUSION: This large multicenter retrospective study shows that there exist a large treatment heterogeneity in advanced MF/SS and differences between USA and non-USA centers but these were not related to survival, while our data reveal that chemotherapy as first treatment is associated with a higher risk of death and/or change of therapy and thus other therapeutic options should be preferable as first treatment approach.


Subject(s)
Mycosis Fungoides/therapy , Sezary Syndrome/therapy , Adolescent , Adult , Aged , Aged, 80 and over , Australia/epidemiology , Brazil/epidemiology , Child , Europe/epidemiology , Female , Humans , Japan/epidemiology , Male , Medical Oncology/methods , Medical Oncology/statistics & numerical data , Middle Aged , Mycosis Fungoides/mortality , Mycosis Fungoides/pathology , Neoplasm Staging , Retrospective Studies , Sezary Syndrome/mortality , Sezary Syndrome/pathology , United States/epidemiology , Young Adult
8.
Med Lav ; 106(5): 325-32, 2015 Sep 09.
Article in English | MEDLINE | ID: mdl-26384258

ABSTRACT

The III Italian Consensus Conference on Pleural Mesothelioma (MM) convened on January 29th 2015. This report presents the conclusions of the 'Epidemiology, Public Health and Occupational Medicine' section. MM incidence in 2011 in Italy was 3.64 per 100,000 person/years in men and 1.32 in women. Incidence trends are starting to level off. Ten percent of cases are due to non-occupational exposure. Incidence among women is very high in Italy, because of both non-occupational and occupational exposure. The removal of asbestos in place is proceeding slowly, with remaining exposure. Recent literature confirms the causal role of chrysotile. Fibrous fluoro-edenite was classified as carcinogenic by IARC (Group 1) on the basis of MM data. A specific type (MWCNT-7) of Carbon Nanotubes was classified 2B. For pleural MM, after about 45 years since first exposure, the incidence trend slowed down; with more studies needed. Cumulative exposure is a proxy of the relevant exposure, but does not allow to distinguish if duration or intensity may possibly play a prominent role, neither to evaluate the temporal sequence of exposures. Studies showed that duration and intensity are independent determinants of MM. Blood related MM are less than 2.5%. The role of BAP1 germline mutations is limited to the BAP1 cancer syndrome, but negligible for sporadic cases. Correct MM diagnosis is baseline; guidelines agree on the importance of the tumor gross appearance and of the hematoxylin-eosin-based histology. Immunohistochemical markers contribute to diagnostic confirmation: the selection depends on morphology, location, and differential diagnosis. The WG suggested that 1) General Cancer Registries and ReNaM Regional Operational Centres (COR) interact and systematically compare MM cases; 2) ReNaM should report results presenting the diagnostic certainty codes and the diagnostic basis, separately; 3) General Cancer Registries and COR should interact with pathologists to assure the up-to-date methodology; 4) Necroscopy should be practiced for validation. Expert referral centres could contribute to the definition of uncertain cases. Health surveillance should aim to all asbestos effects. No diagnostic test is recommended for MM screening. Health surveillance should provide information on risks, medical perspective, and smoking cessation. The economic burden associated to MM was estimated in 250,000 Euro per case.


Subject(s)
Lung Neoplasms , Mesothelioma , Occupational Diseases , Pleural Neoplasms , Asbestos/adverse effects , Humans , Italy , Lung Neoplasms/epidemiology , Lung Neoplasms/etiology , Mesothelioma/epidemiology , Mesothelioma/etiology , Mesothelioma, Malignant , Occupational Diseases/epidemiology , Occupational Diseases/etiology , Occupational Medicine , Pleural Neoplasms/epidemiology , Pleural Neoplasms/etiology , Public Health
9.
Breast Cancer Res Treat ; 148(3): 511-23, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25395316

ABSTRACT

To identify markers of non-response to neoadjuvant chemotherapy (NAC) that could be used in the adjuvant setting. Sixteen pathologists of the European Working Group for Breast Screening Pathology reviewed the core biopsies of breast cancers treated with NAC and recorded the clinico-pathological findings (histological type and grade; estrogen, progesterone receptors, and HER2 status; Ki67; mitotic count; tumor-infiltrating lymphocytes; necrosis) and data regarding the pathological response in corresponding surgical resection specimens. Analyses were carried out in a cohort of 490 cases by comparing the groups of patients showing pathological complete response (pCR) and partial response (pPR) with the group of non-responders (pathological non-response: pNR). Among other parameters, the lobular histotype and the absence of inflammation were significantly more common in pNR (p < 0.001). By ROC curve analyses, cut-off values of 9 mitosis/2 mm(2) and 18% of Ki67-positive cells best discriminated the pNR and pCR + pPR categories (p = 0.018 and < 0.001, respectively). By multivariable analysis, only the cut-off value of 9 mitosis discriminated the different response categories (p = 0.036) in the entire cohort. In the Luminal B/HER2- subgroup, a mitotic count <9, although not statistically significant, showed an OR of 2.7 of pNR. A lobular histotype and the absence of inflammation were independent predictors of pNR (p = 0.024 and <0.001, respectively). Classical morphological parameters, such as lobular histotype and inflammation, confirmed their predictive value in response to NAC, particularly in the Luminal B/HER2- subgroup, which is a challenging breast cancer subtype from a therapeutic point of view. Mitotic count could represent an additional marker but has a poor positive predictive value.


Subject(s)
Breast Neoplasms/drug therapy , Mitosis/genetics , Neoadjuvant Therapy , Biomarkers, Tumor/genetics , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Cell Proliferation/genetics , Disease-Free Survival , Drug Resistance, Neoplasm , Estrogens/genetics , Female , Humans , Receptor, ErbB-2/genetics , Receptors, Progesterone/genetics
10.
Int J Androl ; 35(6): 828-834, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22713104

ABSTRACT

Testicular cancer is one of the most rapidly increasing tumour types but its aetiology is still largely unexplained. Cryptorchidism and familial testicular cancer, established risk factors, explain less than 10% of all cases. Among investigated post-natal factors, early puberty was suggested as a potential risk factor but the topic has been poorly investigated. We undertook a meta-analysis of the effect of age at puberty on testicular cancer risk, attempting at enhancing the homogeneity in the definition of the exposure among studies to obtain valid pooled estimates. Search strategies were conducted in PubMed on December 2011. All markers of puberty onset (age at voice change, age when started shaving and reported age at onset) were considered. We re-categorized age at puberty from all studies into a common three-level variable: younger than peers, same age as peers, older than peers. A total of 391 references were retrieved, of which 12 met the inclusion criteria. Later puberty appeared to be protective. In particular late vs. same age at start shaving gave an OR of 0.84 (95% CI: 0.75-0.95, five studies); late vs. same age at voice change gave an OR of 0.87 (95% CI: 0.75-1.01, five studies); and later age than peers at reported onset of puberty gave an OR of 0.81 (95% CI: 0.73-0.89, eight studies). Early puberty showed no effect on testicular cancer risk. This meta-analysis has found consistent evidence of a decreased risk of testicular cancer in association with later puberty, suggesting that post-natal factors may contribute to testicular cancer risk.


Subject(s)
Age Factors , Puberty , Testicular Neoplasms/physiopathology , Humans , Male , Risk Factors
11.
Early Hum Dev ; 86 Suppl 1: 59-61, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20138718

ABSTRACT

Late-onset sepsis (LOS) affects a large proportion of pre-term neonates in neonatal intensive care units (NICUs) worldwide, with high morbidity and related mortality, and frequent occurrence of severe late neurodevelopmental impairment. Due to the frequency, severity and difficulties in early diagnosis and prompt therapy, prevention is crucial for decreasing the burden of infection-related complications in NICUs. It is well known that feeding with fresh maternal milk, hygiene measures and the cautious use of H2-blockers are related with a decreased risk of developing sepsis. However, evidence from randomised clinical trials exists only for fluconazole in the prevention of fungal infections in the NICU. Lactoferrin is the main whey protein in mammalian milk, and is involved in innate immune host defences. Notably, human lactoferrin can be found at increased concentrations in colostrum and in milk from mothers of premature neonates. Human (hLF) and bovine lactoferrin (bLF) share a high (77%) amino-acid homology, and the same N-terminal peptide responsible for antimicrobial activity, called lactoferricin. In vitro, bLF shows potent direct antimicrobial activity against all types of pathogens, which occurs via anti-cell wall actions and leads to disintegration of the micro-organism's membranes. bLF is also synergistic with many antimicrobials and antifungals, and promotes growth and differentiation of the immature gut. Based on this background data, a randomised clinical trial was recently conducted in very low birth weight pre-term neonates given bLF alone or with the probiotic Lactobacillus GG. The aim of the trial was to assess the ability of bLF to prevent late-onset sepsis of any origin in the studied infants during their stay in the NICU. This article discusses the preliminary data from this study, along with the proposed mechanisms of action of bLF in pre-term infants.


Subject(s)
Infant, Premature , Lactoferrin/physiology , Sepsis/prevention & control , Age of Onset , Animals , Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Cattle , Humans , Infant, Newborn , Infant, Premature/growth & development , Infant, Premature/physiology , Infant, Premature, Diseases/prevention & control , Lactoferrin/chemistry , Lactoferrin/pharmacology , Premature Birth/microbiology , Sepsis/congenital , Sepsis/epidemiology
12.
Eur J Cancer ; 44(6): 830-9, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18329873

ABSTRACT

PURPOSE: The aim of this study was to assess the risk of second malignant neoplasms (SMNs) other than central nervous system (CNS) neoplasms after childhood CNS cancer in an international multicentre study. METHODS: Individual data on cases of CNS cancer in children (0-14 years) and on subsequent SMNs were obtained from 13 population-based cancer registries contributing data for different time periods in 1943-2000. Standardised incidence ratios (SIRs) with 95% confidence intervals (CI), absolute excess risk and cumulative incidence of SMNs were computed. RESULTS: We observed 43 SMNs in 8431 CNS cancer survivors. The SIR was 10.6 (4.85-20.1) for thyroid cancer (nine cases), 2.75 (1.01-5.99) for leukaemia (six cases) and 2.47 (0.90-5.37) for lymphoma (six cases). The SIRs were highest in the first 10 years after CNS cancer diagnosis. The cumulative incidence of non-CNS SMNs was 3.30% (0.95-5.65%) within 45 years after a CNS cancer diagnosis. Within 15 years, the cumulative incidence was highest for cases diagnosed after 1980 (0.56%, 95% CI: 0.29-0.82%). CONCLUSION: This population-based study indicates that about one every 180 survivors of a childhood CNS cancer will develop a non-CNS SMN within the following 15 years. The excess is higher after glioma and embryonal malignant tumour than after another CNS tumour.


Subject(s)
Central Nervous System Neoplasms/epidemiology , Neoplasms, Second Primary/epidemiology , Adolescent , Adult , Aged , Child , Child, Preschool , Epidemiologic Methods , Female , Humans , Infant , Infant, Newborn , Male , Middle Aged , Risk
13.
Occup Environ Med ; 65(5): 354-63, 2008 May.
Article in English | MEDLINE | ID: mdl-18032530

ABSTRACT

OBJECTIVES: Previous studies into occupational risk factors for non-Hodgkin's lymphoma (NHL) in New Zealand have indicated that farmers and meat workers are at increased risk for these neoplasms. A new nationwide case-control study was conducted to assess whether previously observed associations persist and to identify other occupations that may contribute to the risk of NHL in the New Zealand population. METHODS: A total of 291 incident cases of NHL (age 25-70 years) notified to the New Zealand Cancer Registry during 2003 and 2004, and 471 population controls, were interviewed face-to-face. The questionnaire collected demographic information and a full occupational history. The relative risk for NHL associated with ever being employed in particular occupations and industries was calculated by unconditional logistic regression adjusting for age, sex, smoking, ethnicity and socioeconomic status. Estimates were subsequently semi-Bayes adjusted to account for the large number of occupations and industries being considered. RESULTS: An elevated NHL risk was observed for field crop and vegetable growers (OR 2.74, 95% CI 1.04 to 7.25) and horticulture and fruit growing (OR 2.28, 95% CI 1.37 to 3.79), particularly for women (OR 3.44, 95% CI 0.62 to 18.9; OR 3.15, 95% CI 1.50 to 6.61). Sheep and dairy farming was not associated with an increased risk of NHL. Meat processors had an elevated risk (OR 1.97, 95% CI 0.97 to 3.97), as did heavy truck drivers (OR 1.98, 95% CI 0.92 to 4.24), workers employed in metal product manufacturing (OR 1.92, 95% CI 1.12 to 3.28) and cleaners (OR 2.11, 95% CI 1.21 to 3.65). After semi-Bayes adjustment the elevated risks for horticulture and fruit growing, metal product manufacturing and cleaners remained statistically significant, representing the most robust findings of this study. CONCLUSIONS: This study has confirmed that crop farmers and meat workers remain high risk occupations for NHL in New Zealand, and has identified several other occupations and industries of high NHL risk that merit further study.


Subject(s)
Lymphoma, Non-Hodgkin/etiology , Occupational Diseases/etiology , Occupations , Adult , Aged , Agriculture , Case-Control Studies , Female , Humans , Logistic Models , Lymphoma, Non-Hodgkin/prevention & control , Male , Meat-Packing Industry , Middle Aged , New Zealand , Occupational Diseases/prevention & control , Occupational Exposure/analysis , Occupations/statistics & numerical data , Risk Assessment/methods , Risk Factors , Surveys and Questionnaires
15.
Bull Math Biol ; 66(5): 1027-37, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15294417

ABSTRACT

Epidemiologists are interested in using models that incorporate the effects of clustering in the spatial pattern of disease on epidemic dynamics. Bolker (1999, Bull. Math. Biol. 61, 849-874) has developed an approach to study such models based on a moment closure assumption. We show that the assumption works above a threshold initial level of disease that depends on the spatial dispersal of the pathogen. We test an alternative assumption and show that it does not have this limitation. We examine the relation between lattice and continuous-medium implementations of the approach.


Subject(s)
Disease Outbreaks , Epidemiologic Methods , Models, Biological , Plant Diseases , Markov Chains , Plants
16.
J Theor Biol ; 226(2): 125-41, 2004 Jan 21.
Article in English | MEDLINE | ID: mdl-14643183

ABSTRACT

The nature of pathogen transport mechanisms strongly determines the spatial pattern of disease and, through this, the dynamics and persistence of epidemics in plant populations. Up to recently, the range of possible mechanisms or interactions assumed by epidemic models has been limited: either independent of the location of individuals (mean-field models) or restricted to local contacts (between nearest neighbours or decaying exponentially with distance). Real dispersal processes are likely to lie between these two extremes, and many are well described by long-tailed contact kernels such as power laws. We investigate the effect of different spatial dispersal mechanisms on the spatio-temporal spread of disease epidemics by simulating a stochastic Susceptible-infective model motivated by previous data analyses. Both long-term stationary behaviour (in the presence of a control or recovery process) and transient behaviour (which varies widely within and between epidemics) are examined. We demonstrate the relationship between epidemic size and disease pattern (characterized by spatial autocorrelation), and its dependence on dispersal and infectivity parameters. Special attention is given to boundary effects, which can decrease disease levels significantly relative to standard, periodic geometries in cases of long-distance dispersal. We propose and test a definition of transient duration which captures the dependence of transients on dispersal mechanisms. We outline an analytical approach that represents the behaviour of the spatially-explicit model, and use it to prove that the epidemic size is predicted exactly by the mean-field model (in the limit of an infinite system) when dispersal is sufficiently long ranged (i.e. when the power-law exponent a

Subject(s)
Models, Statistical , Plant Diseases , Disease Outbreaks , Disease Transmission, Infectious , Models, Biological
17.
Math Biosci ; 183(1): 15-35, 2003 May.
Article in English | MEDLINE | ID: mdl-12604133

ABSTRACT

Many biologists use population models that are spatial, stochastic and individual based. Analytical methods that describe the behaviour of these models approximately are attracting increasing interest as an alternative to expensive computer simulation. The methods can be employed for both prediction and fitting models to data. Recent work has extended existing (mean field) methods with the aim of accounting for the development of spatial correlations. A common feature is the use of closure approximations for truncating the set of evolution equations for summary statistics. We investigate an analytical approach for spatial and stochastic models where individuals interact according to a generic function of their distance; this extends previous methods for lattice models with interactions between close neighbours, such as the pair approximation. Our study also complements work by Bolker and Pacala (BP) [Theor. Pop. Biol. 52 (1997) 179; Am. Naturalist 153 (1999) 575]: it treats individuals as being spatially discrete (defined on a lattice) rather than as a continuous mass distribution; it tests the accuracy of different closure approximations over parameter space, including the additive moment closure (MC) used by BP and the Kirkwood approximation. The study is done in the context of an susceptible-infected-susceptible epidemic model with primary infection and with secondary infection represented by power-law interactions. MC is numerically unstable or inaccurate in parameter regions with low primary infection (or density-independent birth rates). A modified Kirkwood approximation gives stable and generally accurate transient and long-term solutions; we argue it can be applied to lattice and to continuous-space models as a substitute for MC. We derive a generalisation of the basic reproduction ratio, R(0), for spatial models.


Subject(s)
Demography , Models, Biological , Population Dynamics , Computer Simulation , Forecasting , Plant Diseases , Stochastic Processes , Time Factors
18.
Age Ageing ; 13(6): 349-56, 1984 Nov.
Article in English | MEDLINE | ID: mdl-6334987

ABSTRACT

Mental illness was recorded in 17% of men and 30% of women at the first examination of a random sample of the population of north Edinburgh consisting of 215 men and 272 women aged 62-90 years. Chronic brain syndrome (CBS) was found in 6% of men and 10.7% of women. CBS severe enough to constitute clinical dementia occurred in 3% of the sample. CBS increased in prevalence with age, particularly in women. Depressive illness was found in 3.7% of men and 6.6% of women. Anxiety states were present in 7% of men and 16.5% of women. Physical health and measurements were recorded in the same random sample in respect of ischaemic heart disease, stroke, blood pressure, chronic bronchitis, respiratory function, visual acuity, audiometry, urinary incontinence and food intake. The physical findings related to CBS were poor vision, poor hearing, urinary incontinence and poor diet. Five years later 113 men and 148 women were re-examined. The annual incidence of CBS was 0.4% in men and 1.4% in women. The annual incidence of depressive illness was 0.8% in both sexes, and of anxiety neurosis was 0.3%. Mortality rates were high in subjects with CBS. All moderate/severe cases of CBS had died by the end of seven years, but 15% of the mild cases were alive after 14 years. Prevalence and incidence of CBS in the study were similar to those reported by other authors. Figures for depressive illness and anxiety neurosis tended to be higher than in other surveys.


Subject(s)
Mental Disorders/epidemiology , Morbidity , Aged , Attitude to Health , Bronchitis/epidemiology , Cerebral Infarction/epidemiology , Coronary Disease/epidemiology , Cross-Sectional Studies , Dementia/epidemiology , Female , Humans , Hypertension/epidemiology , Male , Middle Aged , Presbycusis/epidemiology , Visual Acuity
19.
Age Ageing ; 13(1): 42-8, 1984 Jan.
Article in English | MEDLINE | ID: mdl-6702503

ABSTRACT

Handgrip was measured, using a modified sphygmomanometer cuff, in a random sample of 487 older people in Edinburgh in 1968-9. The prevalence of dementia was determined by full psychiatric examination. The error score in the Isaacs-Walkey test was also recorded. Five years later, 261 of the original sample were re-examined. In both examinations treated cross-sectionally there was a significant decrease in grip strength as age increased. However, the mean of the five-year change in individuals did not differ significantly from zero and was not related to age. Handgrip was not significantly related to dementia either at the first examination or as a predictor of new dementia at the five-year examination. Mean handgrip was significantly less at the first examination in those who subsequently died, compared with five-year survivors.


Subject(s)
Dementia/physiopathology , Isometric Contraction , Muscle Contraction , Aged , Dementia/epidemiology , Female , Humans , Longitudinal Studies , Male , Middle Aged , Scotland
20.
Br J Nutr ; 34(3): 517-27, 1975 Nov.
Article in English | MEDLINE | ID: mdl-1201272

ABSTRACT

1. Dietary histories covering 1 week were obtained from 212 men and 263 women, aged 62--90 years, who formed a random sample of the older people living in a defined area of Edinburgh. The histories were validated by 2 d weighed-diet records for 219 of the subjects. 2. Nutrient intakes are given as mean values and standard deviations, and as percentage distributions of intake relative to the recommended intakes of nutrients. Intakes are also related to factors which might affect diet adversely. 3. Mean values obtained suggested that intakes were less than recommended intakes for more nutrients for women than for men, particularly values for energy and vitamin D. Values for percentage distributions indicated that a substantial proportion of all subjects had low intakes of ascorbic acid and vitamin D, that the energy intake of many women was low and that for most nutrients a greater proportion of men than of women had the recommended intake. Factors assocIATED With significant proportions of subjects with less than the recommended intakes were mental illness in women and deafness and severe dyspnoea in men. 4. Possible action to improve the diet of the elderly is discussed.


Subject(s)
Aged , Diet Surveys , Nutrition Surveys , Ascorbic Acid Deficiency/epidemiology , Deafness/epidemiology , Dyspnea/epidemiology , Female , Humans , Male , Mental Disorders/epidemiology , Middle Aged , Nutritional Requirements , Scotland , Sex Factors , Vitamin D Deficiency/epidemiology
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