Suvisaari J M, Haukka J K, Tanskanen A J, Lönnqvist J K
Department of Mental Health and Alcohol Research, National Public Health Institute, Helsinki, Finland.
Psychol Med. 2000 Mar;30(2):315-24. doi: 10.1017/s0033291700001756.
Patients with schizophrenia have a winter-spring excess of births compared with the general population, the cause of which is unresolved. Fluctuations in the magnitude of the seasonal variation may provide clues to its aetiology.
All Finnish patients with schizophrenia born between 1950 and 1969 (N = 15892) were identified from two nationwide health-care registers. Their background demographic information was obtained from the Population Register Centre, which also provided monthly numbers of births in each municipality of Finland as multidimensional tables, with sex and year, month and place of birth as marginals. The incidence of schizophrenia was modelled using Poisson regression analysis, with sex, onset age, birth cohort, place of birth (urban/rural), trend and seasonal variation as explanatory variables. We also constructed a monthly time series and decomposed it into three components--seasonal, trend and remainder.
Seasonal variation of births among patients born in the 1950s, especially between 1955 and 1959, was marked, but decreased among patients born in the 1960s. No interaction between place of birth or sex and seasonal variation was observed. The incidence was higher among the rural-born than the urban-born, but declined more slowly among the urban-born than the rural-born.
The intensity of the factor causing the seasonal variation of births in schizophrenia may be decreasing. Urban birth may be emerging as a risk factor for schizophrenia in Finland, as elsewhere.
与普通人群相比，精神分裂症患者冬春季节出生人数过多，其原因尚未明确。季节变化幅度的波动可能为其病因提供线索。
从两个全国性医疗保健登记处识别出所有1950年至1969年出生的芬兰精神分裂症患者（N = 15892）。他们的背景人口统计学信息来自人口登记中心，该中心还提供了芬兰每个市镇每月的出生人数，以多维表格形式呈现，性别、年份、月份和出生地为边际变量。使用泊松回归分析对精神分裂症的发病率进行建模，将性别、发病年龄、出生队列、出生地（城市/农村）、趋势和季节变化作为解释变量。我们还构建了一个月度时间序列，并将其分解为三个组成部分——季节性、趋势性和余项。
20世纪50年代出生的患者中，尤其是1955年至1959年之间，出生的季节性变化明显，但在20世纪60年代出生的患者中有所下降。未观察到出生地或性别与季节变化之间的相互作用。农村出生者的发病率高于城市出生者，但城市出生者的发病率下降速度比农村出生者慢。
导致精神分裂症患者出生季节变化的因素强度可能正在降低。与其他地方一样，城市出生可能正在成为芬兰精神分裂症的一个风险因素。
