Background:The number of patients with dementia is forecast to grow continuously. However, there are indications that the incidence and prevalence is falling in high-income countries. Objective:To examine whether any effects of declining incidence and prevalence rates of dementia and mild cognitiveimpairment (MCI) were evident in Germany between 2015 and 2019. Methods:The analysis was based on 797 general and 132 specialists (neurological/psychiatric) practices and included 10.1 million patients aged 18 years and older who visited between January 2014 and December 2019 one of the practitioners. The prevalence and incidence of dementia and MCI were demonstrated descriptively. Results:Between 2015 and 2019, the prevalence (incidence) of dementia decreased from 2.18%(0.44%) in 2015 to 2.07%(0.35%) in 2019. A relatively large decrease in the prevalence (incidence) of dementia was observed in patients aged 80 and older, at –1.47%(–0.62%), compared to younger patients, at –0.40%(–0.18%). By contrast, the prevalence and incidence of MCI have remained constant over the years (0.19%to 0.22%and 0.06%, respectively). Overall, the number of patients diagnosed with dementia decreased slightly by 1%while the number of patients diagnosed with MCI increased by 17%, which is caused by continued demographic changes. Conclusion:Our results confirmed the reduction in the prevalence and incidence of dementia and revealed a decrease in the number of patients with dementia despite continued demographic changes. Future studies are warranted to determine whether the results are caused by changing risk and lifestyle factors or changes in medical diagnosis and treatment behavior of the practitioners.

中文翻译：

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2015 年至 2019 年德国一般和专科实践中痴呆症和轻度认知障碍患病率和发病率的趋势

背景：预计痴呆症患者的数量将持续增长。然而，有迹象表明，高收入国家的发病率和流行率正在下降。目的：检查 2015 年至 2019 年德国痴呆症和轻度认知障碍 (MCI) 的发病率和患病率下降是否有任何影响。 2014 年 1 月至 2019 年 12 月期间就诊的 1010 万名 18 岁及以上患者，其中一名从业者。描述性地证明了痴呆和 MCI 的患病率和发病率。结果：2015-2019年痴呆症患病率（发生率）从2015年的2.18%（0.44%）下降到2019年的2.07%（0.35%）。与年轻患者相比，80 岁及以上患者的痴呆症患病率（发生率）下降幅度相对较大，为 –1.47%(–0.62%)，而年轻患者为 –0.40%(–0.18%)。相比之下，MCI 的患病率和发病率多年来一直保持不变（分别为 0.19% 至 0.22% 和 0.06%）。总体而言，诊断为痴呆症的患者人数略有减少 1%，而诊断为 MCI 的患者人数增加了 17%，这是由于人口结构的持续变化所致。结论：我们的结果证实了痴呆症的患病率和发病率的降低，并揭示了尽管人口结构持续变化，但痴呆症患者的数量有所减少。