Eleni Petridou

Human factors in the causation of road traffic crashes

Road traffic crashes (RTCs) are responsible for a substantial fraction of morbidity and mortality and are responsible for more years of life lost than most of human diseases. In this review, we have tried to delineate behavioral factors that collectively represent the principal cause of three out of five RTCs and contribute to the causation of most of the remaining. Although sharp distinctions are not always possible, a classification of behavioral factors is both necessary and feasible. Thus, behavioral factors can be distinguished as (i) those that reduce capability on a long-term basis (inexperience, aging, disease and disability, alcoholism, drug abuse), (ii) those that reduce capability on a short-term basis (drowsiness, fatigue, acute alcohol intoxication, short term drug effects, binge eating, acute psychological stress, temporary distraction), (iii) those that promote risk taking behavior with long-term impact (overestimation of capabilities, macho attitude, habitual speeding, habitual disregard of traffic regulations, indecent driving behavior, non-use of seat belt or helmet, inappropriate sitting while driving, accident proneness) and (iv) those that promote risk taking behavior with short-term impact (moderate ethanol intake, psychotropic drugs, motor vehicle crime, suicidal behavior, compulsive acts). The classification aims to assist in the conceptualization of the problem that may also contribute to behavior modification-based efforts.

The risk profile of childhood leukaemia in Greece: a nationwide case-control study.

The risk profile of childhood leukaemia in Greece was studied through a case-control investigation that included all 153 incident cases of the disease, ascertained throughout the country during 1993 and 1994, and two hospital controls for every case matched for gender, age and place of residence. The data were analysed using conditional logistic regression and the associations are expressed in terms of adjusted odds ratios (OR) and their 95% confidence intervals. Cases were born to mothers of a higher standard education, the OR for an increment of four schooling years being 1.48 (1.17-1.87) and had higher birth weight, the OR for an increment of 500g being 1.36 (1.04-1.77). Pet ownership and birth after a pregnancy with anaemia were associated with increased risk, the ORs being 2.18 (1.14-4.16) and 2.60 (1.39-4.86) respectively. From the frequency analyses, indicative inverse associations were found with birth order, household crowding and previous hospitalization with allergic diseases, whereas indicative positive associations were found with diabetes mellitus during pregnancy and with neonatal jaundice. Substantial or significant elevations were not found with respect to maternal smoking and coffee drinking during pregnancy, diagnostic radiography and ultrasonographic examinations or blood transfusions. A significant inverse association with maternal consumption of alcohol could be due to multiple comparisons, but a detrimental effect can probably be excluded. A non-significant positive association with total shots of viral vaccinations and a weak non-significant inverse association with breast feeding were also found. We interpret the findings of this study as being compatible with acute childhood leukaemia being linked with delayed development of herd immunity to fairly common infectious agents, in conjunction with accelerated perinatal and early post-natal growth.

A role of sunshine in the triggering of suicide

Several reports indicate that suicide follows a seasonal pattern with a dominant peak during the month of maximum daylight. The purpose of this study was to evaluate the hypothesis that sunshine exposure may trigger suicidal behavior. We found a remarkably consistent pattern of seasonality with peak incidence around June in the northern hemisphere and December in the southern hemisphere. Moreover, there was a positive association between the seasonal amplitude of suicide (measured by relative risk) and total sunshine in the corresponding country. These findings indicate that sunshine may have a triggering effect on suicide, and suggests further research in the field of sunshine-regulated hormones, particularly melatonin.

Leptin and insulin growth factor I in relation to breast cancer (Greece).

AbstractObjectives: Because both breast cancer and the hormone leptin are associated with obesity and reproductive phenomena in women, we have examined whether there is a relationship between leptin and breast cancer among premenopausal and postmenopausal women. We have also evaluated in this dataset the association of IGF-I with breast cancer. Methods: Seventy-five cases, diagnosed during mammographic screening, with incident breast cancer were matched for age and type of permanent residence with seventy-five controls from those screened negative in the same study base. Results: There was no evidence for an association between IGF-I and either premenopausal or postmenopausal breast cancer risk or between leptin and postmenopausal breast cancer. Among premenopausal women, however, there was a strong and statistically significant inverse association of leptin with breast cancer. Conclusion: We did not confirm the positive association, reported from other investigations, of IGF-I with premenopausal breast cancer risk. We have found evidence, however, that leptin may be inversely related to breast cancer risk among premenopausal women. The latter finding is not biologically implausible and deserves to be examined in additional datasets.

Low adiponectin levels are associated with renal cell carcinoma: a case-control study.

Adiponectin is a novel endogenous insulin sensitizer, secreted by mature adipocytes. Circulating levels of adiponectin are inversely associated with obesity and insulin resistance. Because obesity is a risk factor for renal cell carcinoma (RCC), we hypothesized that low adiponectin levels are associated with RCC. To evaluate this hypothesis, we conducted a case‐ control study of 70 patients with histologically confirmed RCC and 280 healthy controls matched by gender, age and county of residence. Study subjects were interviewed and blood samples were collected during a 32‐month period in Athens, Greece. Serum adiponectin levels were statistically, significantly and inversely associated with RCC when compared with controls (OR = 0.76, p = 0.05) and this association remained practically unchanged after controlling for BMI; the introduction of waist to hip ratio along with adiponectin in the multiple logistic regression analysis model rendered the association between adiponectin and RCC risk insignificant, indicating that altered levels of adiponectin may mediate the effect of central or intra‐abdominal obesity on RCC. Prospective studies as well as studies exploring underlying mechanisms are needed to fully explore the role of adiponectin in predicting future risk of RCC in humans.

Leptin and Body Mass Index in Relation to Endometrial Cancer Risk

Background/Aim: Because leptin is a hormone associated with obesity and reproduction, we attempted to examine whether there is a relationship between leptin and endometrial cancer. Methods: Cases were 84 women with histologically confirmed incident endometrial cancer, whereas controls were 84 women admitted to the same hospital for small surgical operations. The serum leptin levels were determined in fasting morning blood samples by using radioimmunoassay. The mean values of leptin levels among cases and controls were compared with simple t test, and the data were further analyzed using multiple logistic regression procedures. Results: The serum leptin levels were 36.7 ± (SD) 25.7 ng/ml among cases and 26.9 ± 19.8 ng/ml among controls (p = 0.006). After adjustment for known risk factors of endometrial cancer, components of the insulin-like growth factor system did not confound the association of leptin with endometrial cancer, but this association was eliminated, when the body mass index was adjusted for. Thus, the odds ratio for an increment of 1 SD of blood leptin was 1.52 (p = 0.03) before adjustment for body mass index, but only 1.13 (p = 0.62) after adjustment for it. Conclusions: In a case-control study of incident endometrial cancer in Greece, we found evidence that leptin is strongly positively associated with endometrial cancer. It cannot be conclusively inferred, however, whether leptin elevation, as a consequence of obesity, plays a role in endometrial carcinogenesis or whether it is a simple correlate of obesity.

Assessing the burden of injury in six European countries

OBJECTIVE To assess injury-related mortality, disability and disability-adjusted life years (DALYs) in six European countries. METHODS Epidemiological data (hospital discharge registers, emergency department registers, mortality databases) were obtained for Austria, Denmark, Ireland, Netherlands, Norway, and the United Kingdom (England and Wales). For each country, the burden of injury was estimated in years lost due to premature mortality (YLL), years lived with disability (YLD), and DALYs (per 1000 persons). FINDINGS We observed marked differences in the burden of injury between countries. Austria lost the largest number of DALYs (25 per 1000 persons), followed by Denmark, Norway and Ireland (17-20 per 1000 persons). In the Netherlands and United Kingdom, the total burden due to injuries was relatively low (12 per 1000 persons). The variation between countries was attributable to a high variation in premature mortality (YLL varied from 9-17 per 1000 persons) and disability (YLD varied from 2-8 per 1000 persons). In all countries, males aged 25-44 years represented one third of the total injury burden, mainly due to traffic and intentional injuries. Spinal cord injury and skull-brain injury resulted in the highest burden due to permanent disability. CONCLUSION The burden of injury varies considerably among the six participating European countries, but males aged 15-24 years are responsible for a disproportionate share of the assessed burden of injury in all countries. Consistent injury control policy is supported by high-quality summary measures of population health. There is an urgent need for standardized data on the incidence and functional consequences of injury.

Breast-feeding and maternal smoking in the etiology of Crohn's disease and ulcerative colitis in childhood

Medical records concerning pediatric or adolescent patients first diagnosed with Crohns disease or ulcerative colitis in two New York hospitals during a 5-year period (1986 to 1990) were abstracted, and information concerning sex, age, race, birthplace, sibship size, birth order, maternal age at birth, month of birth, duration of breast-feeding, and maternal smoking was recorded. Medical records of patients presenting at the respective pediatric gastroenterology departments immediately before or after the patients with inflammatory bowel disease were seen were also abstracted in order to generate a control series. Data concerning 68 patients with Crohns disease, 39 patients with ulcerative colitis, and 202 control patients were analyzed through multiple logistic regression. Breast-feeding was negatively associated with Crohns disease (P approximately 0.04) and ulcerative colitis (P approximately 0.07), with relative risk point estimates around 0.5 and with evidence of duration-dependent trends in both instances. There was no evidence of association of either disease with maternal age at birth, birth order, maternal smoking, or season of birth.

Risk factors for childhood burn injuries: a case-control study from Greece

During a 12-month period 239 children who presented with a burn injury at the Emergency Department of a teaching childrens hospital in Athens, with city-wide coverage, and 239 gender- and age-matched controls with minor non-injury ailments were interviewed. The questionnaire covered sociodemographic characteristics of the children and their families, information allowing the construction of a burn avoidance index in their homes and items from the Achenback scale that were synthesized into a child activity score. The data were analyzed through conditional logistic regression. In general, socio-demographic variables were not of overwhelming importance, although some of the findings indicate that supervision lapses and barefoot walking of gypsy children increase the risk of burn injuries. The kitchen in an inherently high risk place for injuries and the powerful inverse association of the burn avoidance index with burn injury risk points towards steps that could be easily taken and impart substantial protection. There was no evidence in this study of burn injury proneness or that hyperactivity of the child increased the risk of burn injury; indeed, the results point in the opposite direction. Our results strongly support the view that childhood burn injuries are largely environmentally conditioned and, accordingly, easily preventable.

Doping use among tertiary education students in six developed countries

Data on doping among young non-professional athletes are scarce. In order to estimate the prevalence and predictors of doping use, a standardized, anonymous questionnaire was self-administered by 2650 tertiary education students from five European Union countries (Finland, France, Germany, Greece, Italy) and Israel. The reported usage rate of a doping agent (at least once) was 2.6%, with no significant variation in the frequency of doping reporting among the participating countries. Doping was, however, less common among students of biomedical schools (OR: 0.49, 95% CI: 0.27–0.89) and was higher among males (OR: 2.16, 95% CI: 1.25–3.74). Students, who use to drink coffee or recall frequent occasions of involvement in drunkenness episodes, were more likely (twice and three times, respectively) to report doping, and students using nutritional supplements or having participated in a major athletic event were more likely (four times and twice, respectively) to report doping in comparison with students who do not. Of note is the high odds ratio for reporting individual doping when having a friend who uses doping (OR: 8.61, 95% CI: 4.49–16.53). Given the large size of the physically active young individuals in the population and the small number of professional athletes, doping in the general population may be, in absolute terms, as sizeable problem as it is among the professional athletes. There was evidence that high-risk behaviour and supplement use increased the risk of doping.