Cold weather is a predisposing factor for testicular torsion in a tropical country. A retrospective study

CONTEXT AND OBJECTIVE:Testicular torsion is a medical and urological emergency because it can lead to loss of the organ. The theory of seasonal testicular torsion occurrence is based on studies from institutions located in cold and temperate regions. The objective here was to determine whether cold weather is associated with higher incidence of testicular torsion in a tropical country, such as Brazil.DESIGN AND SETTING:Retrospective study, conducted in a tertiary and teaching hospital.METHODS:Patients with acute testicular torsion confirmed by surgery between April 2006 and March 2011 were studied. Information on weather conditions at the time of symptom onset was collected.RESULTS:A total of 64 testicular torsion cases were identified. The months with the highest incidences of testicular torsion were June (16%), July (19%) and August (11%), which had the lowest mean temperatures, of 17.6 °C, 16.4 °C and 18.2 °C, respectively. Eleven percent of cases occurred during spring (October to December), 16% occurred in summer (January to March), 34% occurred in fall (April to June) and 39% occurred in winter (July to September). There was a significant association between the incidence of testicular torsion and the season (fall and winter), P &lt; 0.001.CONCLUSIONS:Testicular torsion follows a seasonal association even in a tropical country, and is more frequent in the colder months of the year, namely fall and winter, when almost three-quarters of the cases occurred. These observations add further evidence that cold weather has an etiologic role in testicular torsion occurrence.研究背景与目的：睾丸扭转（Testicular torsion）属于内科与泌尿外科急症，可导致患侧睾丸丢失。睾丸扭转的季节发生理论，源于寒冷及温带地区相关机构开展的研究。本研究旨在明确在巴西这类热带国家中，寒冷天气是否与睾丸扭转发病率升高存在关联。 研究设计与研究地点：本研究为一项回顾性研究，在一所三级教学医院开展。 研究方法：纳入2006年4月至2011年3月经手术确诊的急性睾丸扭转患者，收集患者症状发作时的气象条件信息。 研究结果：共纳入64例睾丸扭转病例。发病率位居前三的月份为6月（16%）、7月（19%）与8月（11%），上述月份的平均气温分别为17.6℃、16.4℃与18.2℃，为全年平均气温最低的时段。春季（10月至12月）病例占比11%，夏季（1月至3月）占比16%，秋季（4月至6月）占比34%，冬季（7月至9月）占比39%。睾丸扭转发病率与季节（秋季与冬季）存在显著相关性（P<0.001）。 研究结论：即便在热带国家，睾丸扭转仍存在季节相关性，且在每年较寒冷的秋季与冬季更为高发，该时段病例占比近四分之三。本研究结果进一步证实寒冷天气在睾丸扭转发病中具有病因学作用。