Makris Georgios D, Reutfors Johan, Andersen Morten, White Richard A, Ekselius Lisa, Papadopoulos Fotios C
Department of Neuroscience, Psychiatry, Uppsala University Hospital, Uppsala University, Uppsala, Sweden.
Centre for Pharmacoepidemiology, Department of Medicine Solna, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden.
J Affect Disord. 2017 Jun;215:245-255. doi: 10.1016/j.jad.2017.03.028. Epub 2017 Mar 10.
Decreased binding capacity of SERT in the prefrontal cortex has been observed in both suicide victims and suicide attempters. Moreover, some studies have shown that SERT has a seasonal variation with lower binding capacity in the spring and summer, which coincides with a seasonal peak of suicides. Our aim was to explore whether the season of treatment initiation with antidepressants is associated with suicide or suicide attempt and compare it with the underlying suicide seasonality in the general population.
Using Swedish registers, patients who initiated treatment with an antidepressant were followed up to three months for suicidal behavior. Cox regression analyses were used. Results were compared with the underlying seasonal pattern by calculating standardized mortality ratios (SMRs) for suicides and standardized incidence ratios (SIRs) for suicide attempts.
Patients aged ≥65 years had higher risk for suicide when initiating antidepressant treatment in the summer, and also a higher risk for suicide attempt when initiating treatment in the spring and summer. Young patients (0-24 years) presented a higher risk for suicide attempt when initiating treatment in the autumn. Patients with previous suicide attempt had a seasonal pattern, with a higher risk to carry out a suicide attempt in the summer and autumn. Results from the SMR and SIR calculations numerically support these findings.
We used information of filling an antidepressant prescription as a proxy of actual antidepressant treatment. Patients with combination, augmentation therapy or those switching antidepressant during follow-up were excluded. Thus, our results refer to less complicated psychopathology.
Our results indicate an interaction between biological and health care-related factors for the observed seasonal pattern of suicidal behavior in the elderly, whereas psychological and societal factors may be more important for the seasonality observed in the younger patients.
在自杀受害者和自杀未遂者中均观察到前额叶皮质中5-羟色胺转运体（SERT）的结合能力下降。此外，一些研究表明，SERT存在季节性变化，在春季和夏季结合能力较低，这与自杀的季节性高峰相吻合。我们的目的是探讨开始使用抗抑郁药治疗的季节是否与自杀或自杀未遂有关，并将其与普通人群潜在的自杀季节性进行比较。
利用瑞典的登记资料，对开始使用抗抑郁药治疗的患者进行长达三个月的自杀行为随访。采用Cox回归分析。通过计算自杀的标准化死亡比（SMR）和自杀未遂的标准化发病比（SIR），将结果与潜在的季节性模式进行比较。
≥65岁的患者在夏季开始抗抑郁药治疗时自杀风险较高，在春季和夏季开始治疗时自杀未遂风险也较高。年轻患者（0-24岁）在秋季开始治疗时自杀未遂风险较高。有过自杀未遂史的患者呈现出季节性模式，在夏季和秋季进行自杀未遂的风险较高。SMR和SIR计算结果在数值上支持了这些发现。
我们将填写抗抑郁药处方的信息用作实际抗抑郁药治疗的替代指标。排除了接受联合治疗、增效治疗或在随访期间更换抗抑郁药的患者。因此，我们的结果涉及不太复杂的精神病理学情况。
我们的结果表明，在老年人中观察到的自杀行为季节性模式中，生物学因素和与医疗保健相关的因素之间存在相互作用，而心理和社会因素可能对年轻患者中观察到的季节性更为重要。
