Author's replyBMJ 1996; 312 doi: https://doi.org/10.1136/bmj.312.7040.1227c (Published 11 May 1996) Cite this as: BMJ 1996;312:1227
- H Bounameaux
- Senior lecturer Division of Angiology and Haemostasis, Department of Internal Medicine, University Hospital of Geneva, Geneva, Switzerland
EDITOR,—T M Allan and A S Douglas's additional data on the increased risk of fatal pulmonary embolism in the cold months are interesting. As we stated in our paper, however, these data do not necessarily contradict our observation of a lack of seasonal variation in deep vein thrombosis, the source of pulmonary embolism. Indeed, comorbidities related to the winter might contribute to a reduced tolerance to small emboli. Alun Tomkinson questions our crude grouping of events by monthly or arbitrary seasonal periods, though this makes sense in a study that aimed at assessing monthly and seasonal variations. Admittedly, our data do not exclude the possibility of daily variations in the occurrence of deep vein thrombosis related to changes in ambient temperature (or barometric pressure or humidity). Since we had no access to these meteorological data, we are unable to study this interesting hypothesis.