Ramirez-Lassepas M, Haus E, Lakatua D J, Sackett L, Swoyer J
Ann Neurol. 1980 Nov;8(5):539-41. doi: 10.1002/ana.410080512.
Seasonal periodicity in the onset of spontaneous intracerebral hemorrhage was studied in 118 consecutive cases occurring during a six-year span. The patients were urban residents of eastern Minnesota, a region characterized by wide seasonal fluctuations in daylight and temperature. The greatest number of cases consistently occurred each year during January and February. Circannual (about one year) periodicity was demonstrated by statistical analysis using rhythmometric techniques. This periodicity coincided with that reported for mortality from cerebrovascular and cardiovascular diseases in the United States and elsewhere. Available information suggests that in populations at high risk for vascular diseases, climatic conditions might act as synchronizers to endogenous rhythms influencing the periodic occurrence of pathological vascular events.
在一项对连续118例在六年期间发生的自发性脑出血病例的研究中，研究了其发病的季节性周期。这些患者是明尼苏达州东部的城市居民，该地区的特点是日光和温度有很大的季节性波动。每年1月和2月出现的病例数始终最多。使用节律测量技术进行统计分析表明存在年周期（约一年）。这种周期性与美国和其他地方报道的脑血管和心血管疾病死亡率的周期性一致。现有信息表明，在血管疾病高危人群中，气候条件可能作为内源性节律的同步器，影响病理性血管事件的周期性发生。
