Discontinuation of anticoagulation or antiaggregation treatment may be safe in patients with primary antiphospholipid syndrome when antiphospholipid antibodies became persistently negative.

Recommended treatment for patients with primary antiphospholipid syndrome (APS) after a thrombotic event is long-term anticoagulation. Few patients with APS and previously positive antiphospholipid antibodies (aPL) may become negative over time. It is still not exactly known how to treat these patients when aPL become persistently negative. We described the follow-up of 11 primary APS patients whose aPL become persistently negative and in whom thromboprophylaxis was discontinued. The primary end-point was the recurrence of thrombosis in patients with previous thrombotic event and a first thrombotic event in women with previous obstetric APS. Ten (90%) patients were female. Seven (64%) patients had a history of deep venous thrombosis, two of them with pulmonary embolism, and four (36%) women had recurrent miscarriage. Lupus anticoagulant (LAC) was the aPL most frequently detected (82%). Two patients had both LAC and IgG anticardiolipin antibodies. No new thrombotic episode was observed after a median follow-up period of 20 months. Anticoagulation or antiaggregation could be discontinued in some peculiar patients with low-risk primary APS whose aPL become persistently negative. However, studies including a larger number of patients are required to confirm these results.

The association of age, sex and helmet use with the risk of death for occupants of two-wheeled motor vehicles involved in traffic crashes in Spain.

BACKGROUND: This study was designed to separate the association of age, sex and helmet use with the risk of death for occupants of two-wheeled motor vehicles (TWMV) involved in crashes into its two theoretical components: severity of the crash and occupant resilience. METHODS: We analyzed the retrospective cohort comprising all 48 016 pairs of drivers and passengers aged 14 years or more in TWMV involved in crashes with victims in Spain from 1993 to 2007 recorded in the Spanish traffic crash registry. The outcome (death or survival), age, sex and helmet use was known for both occupants. Adjusted relative risks (RR) for the association of age, sex and helmet with the risk of death were calculated with Poisson regression models. RESULTS: Each 1-year increase in age was related with a 3% increase in the risk of death related with lower resilience. The severity-dependent RR of death was 1.84 for male sex and 0.86 for non-helmet use, and the resilience-dependent RR was 0.72 and 2.53, respectively. CONCLUSIONS: The direction and magnitude of the association between age, sex and helmet use and the risk of death of an occupant of a TWMV involved in a crash changed depending on which component of risk was considered: crash severity or occupant resilience. Specifically, female sex and non-helmet use seemed to be associated with crashes of lower severity, but together with increased age they were also related with lower resilience to the energy released in the crash, and therefore with a higher risk of death after adjustment for crash severity. This should be taken into account when assessing the association of individual factors with the risk of death after a crash.

[Effect of environmental factors on the risk of death for drivers of two-wheeled motorized vehicles involved in road crashes]. / Efecto de las circunstancias ambientales sobre el riesgo de defunción de los conductores de vehículos de dos ruedas de motor implicados en accidentes de tráfico.

OBJECTIVES: To assess the effect of environmental factors on the risk of death for drivers of two-wheeled motorized vehicles (TWMV) after a crash. METHODS: We studied a case series comprising all 309,626 drivers of TWMV involved in road crashes with victims compiled by the Spanish Department of Transportation from 1993 to 2002. The dependent variable was death of the driver. Environmental factors included temporal variables (year, month, day and hour of the crash) and spatial variables (area where the accident took place and light conditions, among others). Confounding variables related to the driver (age, sex, helmet use), the vehicle, and the type of crash were also recorded. Poisson regression models were constructed to obtain crude and adjusted relative risks for each environmental condition. RESULTS: In the adjusted analysis, no association was found between most time-related factors and the risk of death, with the exception of an increased risk in the early hours of the morning. The risk of death was much greater for crashes on open roads (especially highways and motorways) than in urban areas, where the risk of death increased as the size of the town decreased. CONCLUSIONS: After adjustment for several confounders, the only environmental factors related to the risk of death in TWMV drivers after a crash were the area when the crash occurred, and (more weakly) the time of day when it occurred.

Efecto de las circunstancias ambientales sobre el riesgo de defunción de los conductores de vehículos de dos ruedas de motor implicados en accidentes de tráfico / Effect of environmental factors on the risk of death for drivers of two-wheeled motorized vehicles involved in road crashes

Objetivos: Valorar el efecto de las circunstancias ambientales sobre el riesgo de muerte de los conductores de vehículos de dos ruedas de motor (VDRM) tras un accidente de tráfico. Métodos: Se ha estudiado la serie de casos formada por los 309.626 conductores de VDRM implicados en accidentes de tráfico con víctimas en España, entre 1993 y 2002, recogidos por la Dirección General de Tráfico. La variable dependiente ha sido la defunción del conductor. Como variables ambientales se han considerado factores temporales (año, mes, día y hora) y espaciales (zona del accidente, iluminación, entre otros). También se han recogido potenciales factores de confusión dependientes del conductor (edad, sexo, uso de casco), del vehículo y el tipo de accidente. Se han obtenido, mediante modelos de regresión de Poisson, riesgos relativos crudos y ajustados para cada categoría ambiental. Resultados: Para la mayoría de las variables temporales, no hay asociación con el riesgo de defunción en el análisis ajustado, a excepción de un mayor riesgo para la conducción de madrugada. El riesgo aumenta fuertemente en carretera (especialmente autopistas y autovías) con respecto a las zonas urbanas, para las que hay una clara relación dosis-respuesta entre un menor tamaño del municipio y una mayor letalidad. Conclusiones: Tras ajustar por los factores de riesgo dependientes del conductor, el efecto de los factores ambientales sobre el riesgo de muerte del conductor de un VDRM tras el accidente se circunscribe a la zona donde se produce el accidente y, en menor medida, a la hora en que ocurre

Objectives: To assess the effect of environmental factors on the risk of death for drivers of two-wheeled motorized vehicles (TWMV) after a crash. Methods: We studied a case series comprising all 309,626 drivers of TWMV involved in road crashes with victims compiled by the Spanish Department of Transportation from 1993 to 2002. The dependent variable was death of the driver. Environmental factors included temporal variables (year, month, day and hour of the crash) and spatial variables (area where the accident took place and light conditions, among others). Confounding variables related to the driver (age, sex, helmet use), the vehicle, and the type of crash were also recorded. Poisson regression models were constructed to obtain crude and adjusted relative risks for each environmental condition. Results: In the adjusted analysis, no association was found between most time-related factors and the risk of death, with the exception of an increased risk in the early hours of the morning. The risk of death was much greater for crashes on open roads (especially highways and motorways) than in urban areas, where the risk of death increased as the size of the town decreased. Conclusions: After adjustment for several confounders, the only environmental factors related to the risk of death in TWMV drivers after a crash were the area when the crash occurred, and (more weakly) the time of day when it occurred