Pablo Lardelli-Claret

Exposure to pesticides and cryptorchidism: geographical evidence of a possible association

Synthetic hormone-disrupting chemicals may play a role in the increased frequency of cryptorchidism observed in some studies. We used a spatial ecological design to search for variations in orchidopexy rates in the province of Granada in Spain and to search for relationships between these differences and geographical variations in exposure to pesticides. Orchidopexy rates were estimated for the period from 1980 to 1991 in all municipalities and health care districts served by the University of Granada Hospital. A random sample of males of the same age (1-16 years) admitted for any reason during the same period was used to estimate inpatient control rates. Each municipality was assigned to one of four levels of pesticide use. We used Poisson homogeneity tests to detect significant differences in rates of orchidopexy between districts and between levels of pesticide use. Poisson and logistic regression models were also used to estimate the strength of association between orchidopexy and level of pesticide use. Orchidopexy rates tended to be higher in districts near the Mediterranean coast where intensive farming is widespread. The city of Granada, where the reference hospital is located, also had higher figures both for orchidopexy and inpatient control rates. Regression models showed that the strength of association between orchidopexy and level of pesticide use tended to increase with higher levels of use, with the exception of level 0 (mainly in the city of Granada). Our results are compatible with a hypothetical association between exposure to hormone-disruptive chemicals and the induction of cryptorchidism. Several methodological limitations in the design make it necessary to evaluate the results with caution. ImagesFigure 1.Figure 2.Figure 3.

The influence of passengers on the risk of the driver causing a car collision in Spain. Analysis of collisions from 1990 to 1999.

OBJECTIVE To determine how the number of passengers, their age and their sex influence the risk of different types of Spanish drivers causing a collision between two or more cars. METHODS We selected, from the Spanish database of traffic crashes resulting in personal injuries or death, those collisions between two or more cars that occurred between 1990 and 1999 in which only one of the involved drivers committed a driving infraction. These drivers were considered the cases; non-infractor drivers were considered their matched controls. We collected information on the number, age and sex of the passengers in each vehicle, along with some potential confounding variables of the drivers and the vehicles involved. Crude and adjusted odds ratios were calculated for the main categories of driver and passenger. RESULTS A protective effect for the presence of passengers was detected (adjusted odds ratio: 0.69; 95% CI: 0.67-0.70). The protective effect was higher for drivers aged more than 45 years and lower for the youngest drivers (<24 years old). The strongest association was observed for female passengers who accompanied male drivers. The protective effect was lower for passengers older than 64 years. CONCLUSIONS Our results suggest that drivers are less likely to cause a car collision between two or more cars that results in personal injuries or death when they are accompanied by passengers, regardless of driver or passenger characteristics.

Driver dependent factors and the risk of causing a collision for two wheeled motor vehicles

Objective: To assess the effect of driver dependent factors on the risk of causing a collision for two wheeled motor vehicles (TWMVs). Design: Case control study. Setting: Spain, from 1993 to 2002. Subjects: All drivers of TWMVs involved in the 181 551 collisions between two vehicles recorded in the Spanish registry which did not involve pedestrians, and in which at least one of the vehicles was a TWMV and only one driver had committed a driving infraction. The infractor and non-infractor drivers constituted the case and control groups, respectively. Main outcome measures: Logistic regression analyses were used to obtain crude and adjusted odds ratio estimates for each of the driver related factors recorded in the registry (age, sex, nationality, psychophysical factors, and speeding infractions, among others). Results: Inappropriate speed was the variable with the greatest influence on the risk of causing a collision, followed by excessive speed and driving under the influence of alcohol. Younger and older drivers, foreign drivers, and driving without a valid license were also associated with a higher risk of causing a collision. In contrast, helmet use, female sex, and longer time in possession of a driving license were associated with a lower risk. Conclusions: Although the main driver dependent factors related to the risk of causing a collision for a TWMV were similar to those documented for four wheeled vehicles, several differences in the pattern of associations support the need to study moped and motorcycle crashes separately from crashes involving other types of vehicles.

Proportion of Hospital Deaths Associated with Adverse Events

OBJECTIVES To determine the fraction of hospital deaths potentially associated with the occurrence of adverse events (AE). DESIGN A paired (1:1) case-control study. SETTING An 800-bed, teaching tertiary care hospital. PATIENTS All patients older than 14 years admitted to the hospital between January 1, 1990, and January 1, 1991, were eligible. All 524 consecutive deaths (death rate of 3.74%) that occurred in the hospital comprised the case group. For each case, a control patient was matched for both primary diagnosis on admission and admission date. MEASUREMENTS The proportion of hospital deaths associated with adverse events (defined as problems of any nature and seriousness faced by the patient during hospitalization, and potentially traceable to clinical or administrative management) was estimated from attributable risks adjusted for age, sex, service, severity of illness, length of stay, and quality of the medical record. RESULTS For stays longer than 48 hours, the adjusted attributable risk for all adverse events was estimated to be 0.51 (0.40-0.61). When the data were stratified according to the category of adverse event, the attributable risks remained significant except for administrative problems. The greatest proportion of deaths associated with adverse events was observed for surgical adverse events [0.56 (0.38-0.71)] and nosocomial infection [0.22 (0.14-0.28)]. CONCLUSIONS A significant proportion of intrahospital deaths were associated with AE. These results suggest the need to consider programs focused on the prevention of mortality from AE.

Proportion of hospital deaths potentially attributable to nosocomial infection.

OBJECTIVE To determine the fraction of hospital deaths potentially associated with nosocomial infection (NI). DESIGN A matched (1:1) case-control study. SETTING An 800-bed, tertiary-care, teaching hospital. PATIENTS All patients older than 14 years who were admitted to the hospital between January 1, 1990, and January 1, 1991, were eligible. All 524 consecutive deaths that occurred in the hospital comprised the case group. For each case, a control patient was matched for primary admission diagnosis and admission date. OUTCOME MEASURES The proportion of hospital deaths potentially associated with NI was estimated from the population attributable risk (PAR) adjusted for age, gender, service, severity of illness, length of stay, and quality of the medical record. RESULTS For stays longer than 48 hours, the PAR for all NIs was estimated to be 21.3% (95% confidence interval [CI95], 16.8%-30.5%). The greatest proportion of deaths potentially associated with NIs was observed in patients with only one infection (PAR, 15.0%; CI95, 10.9%-22.6%) and bacteremia or sepsis (PAR, 7.7%; CI95, 4.6%-11.6%). CONCLUSIONS NIs are associated with a large proportion of intrahospital deaths. This information may help clinicians and healthcare managers to assess the impact of programs for the prevention and control of NIs on intrahospital death.

Risk compensation theory and voluntary helmet use by cyclists in Spain

Objective: To obtain empirical data that might support or refute the existence of a risk compensation mechanism in connection with voluntary helmet use by Spanish cyclists. Design: A retrospective case series. Setting: Spain, from 1990 to 1999. Subjects: All 22 814 cyclists involved in traffic crashes with victims, recorded in the Spanish Register of Traffic Crashes with Victims, for whom information regarding helmet use was available. Main outcome measures: Crude and adjusted odds ratios for the relation between committing a traffic violation and using a helmet. Results: Fifty four percent of the cyclists committed a traffic violation other than a speeding infraction. Committing a traffic violation was associated with a lower frequency of helmet use (adjusted odds ratio (aOR) 0.63, 95% confidence interval (CI) 0.58 to 0.69). Cycling at excessive or dangerous speed, a violation observed in 4.5% of the sample, was not significantly associated with helmet use either alone (aOR 0.95, 95% CI 0.56 to 1.61) or in combination with any other violation (aOR 0.97, 95% CI 0.79 to 1.20). Conclusions: The results suggest that the subgroup of cyclists with a higher risk of suffering a traffic crash are also those in which the health consequences of the crash will probably be higher. Although the findings do not support the existence of a strong risk compensation mechanism among helmeted cyclists, this possibility cannot be ruled out.

Impact of different levels of carbohydrate intolerance on neonatal outcomes classically associated with gestational diabetes mellitus

OBJECTIVE To compare the influence of different levels of carbohydrate intolerance on neonatal outcomes. STUDY DESIGN The cohort constituted by the 1962 pregnant women screened for gestational diabetes who gave birth at the University Hospital of Granada (Spain) in the year 1995 was followed retrospectively. Women were classified into three groups: diagnosis of gestational diabetes, positive screen but non-gestational diabetes, and negative screen. Frequency of adverse newborn outcomes were quantified for each group and compared for statistical significance. RESULTS Gestational diabetes was associated with a greater incidence of high birth weight, hypoglycemia and hypocalcemia. Adequate metabolic control of the illness reduced the risk of adverse outcomes. Birth weight traced a positive slope with respect to the degree of carbohydrate intolerance. Regardless of carbohydrate intolerance, macrosomia was always higher among gravidae with gestational diabetes risk factors than among women without them. CONCLUSION Both maternal gestational diabetes risk factors and greater carbohydrate intolerance in gravidae are associated with an increase in adverse newborn outcomes.

Risk factors for causing road crashes involving cyclists: An application of a quasi-induced exposure method

A quasi-induced exposure approach was applied to the Spanish Register of Traffic Crashes to identify driver- and vehicle-related factors associated with the risk of causing a road crash involving a cyclist in Spain from 1993 to 2009. We analyzed 19,007 collisions between a bicycle and another vehicle in which only one of the drivers committed an infraction, and 13,540 records that included the group of non-infractor cyclists in the above collisions plus cyclists involved in single-bicycle crashes. Adjusted odds ratios were calculated for being responsible for each type of crash for each factor considered. Age from 10 to 19 years, male sex, alcohol or drug consumption and non-helmet use were cyclist-related variables associated with a higher risk of crash, whereas cycling more than 1h increased only the risk of single crashes. Bicycles with brake defects and ridden by two occupants were also at higher risk of involvement in a crash, whereas light defects were associated only with collisions with another vehicle. For drivers of the other vehicle, age more than 60 years, alcohol, not using safety devices and nonprofessional drivers were at higher risk. The risk of colliding with a bicycle was higher for mopeds than for passenger cars.

Predictive value of a screen for gestational diabetes mellitus : influence of associated risk factors

Background. There is a need for solid evidence of the relative advantages of universal vs. selective screening for gestational diabetes mellitus. Our study of a broad obstetric population determines the positive predictive value of the 50‐g oral glucose challenge test for screening in the presence and absence of classical gestational diabetes risk factors.

Association of main driver-dependent risk factors with the risk of causing a vehicle collision in Spain, 1990–1999

PURPOSE To assess the strength of association of main driver-dependent risk factors with the risk of causing a collision between vehicles in Spain, from 1990 to 1999. METHODS The data for this paired-by-collision, case-control study were obtained from the Spanish Dirección General de Tráfico traffic crash database. The study included all 220284 collisions involving two or more vehicles with four or more wheels, in which only one of the drivers involved committed an infraction. Infractor drivers comprised the case group; noninfractor drivers involved in the same collision were their corresponding paired controls. RESULTS All driver-dependent factors were associated with the risk of causing a collision. The highest adjusted odds ratio estimates were obtained for sleepiness (64.35; CI, 45.12-91.79), inappropriate speed (28.33; CI, 26.37-30.44), and driving under the influence of alcohol with a positive breath test (22.32; CI, 19.64-25.37). An increase in the number of years in possession of a driving license showed a protective effect, albeit the strength of the effect decreased as age increased. CONCLUSIONS Our results emphasize the urgent need to implement strategies aimed mainly at controlling speeding, sleepiness, and alcohol consumption before driving-the main driver-dependent risk factors for causing a vehicle collision.