PPPD 1: Persistent Posture-Perceived Dizziness Has Three Subtypes

，-（PPPD），，“”，（PPV）、-（SMD）、（VV）（CSD）
。
2017，Barany4，PPPD，/
。
，PPPD4？？？？
。
：Tinyel，
。
PPPD（NPQ）、（DHI）、（HADS）（、、、）108PPPD，PPPD3，3，PPPD，PPV、SMD、VV、CSD（，PPPD≠PPV+SMD+VV+CSD）
。
1 PPPD（NPQ）01First Step：32 NPQ33——/、，NPQ
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A series of statistical analyses were carried out after the assessment, and 3 worsening factors were obtained: factor 1 (related to problems related to visual stimulation): visual factors, factor 2 (related to problems related to walking and active movement): active movement factors, factors 3 (related to passive movement and standing-related problems): Passive movement/standing factor
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Among the three factors, visual factor was the primary factor aggravating the symptoms of PPPD
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 02Second Step: Three subtypes Based on the discovery of three exacerbating factors, after a series of integration and analysis, three subtypes of PPPD were obtained
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Subtype 1 (higher score on visual factors): Visually dominant, Subtype 2 (higher active motor score): Active motor dominant, Subtype 3 (no dominant worsening factor, affected by 3 worsening factors similar): Hybrid
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As can be seen from the naming of subtypes, the classification of subtypes is directly related to exacerbation factors
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 Figure 3 Three subtypes of PPPD and their corresponding exacerbating factors 03Third Step: Demographic and clinical characteristics What is the use of finding subtypes of PPPD? There were no significant differences among the three subtypes in terms of gender, course of disease, DHI score, HADS score, and even various vestibular function tests (instantly began to suspect that the enthusiasm of island scholars would be wasted?)
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However, there is a "but" in everything, and there is hope
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Some results are still clinically relevant, for example, the mean age of subtype 2 (active motor-dominant) was significantly greater than that of subtype 1 (visual-dominant)
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Although it is almost always "unclear" when it comes to "mechanism", (the "but" that represents hope appears again) some scientific reasoning can still be done, for example, the mechanism of factor 1 (visual factor) It is to increase the dependence of vision on spatial orientation.
The mechanism of factor 2 (active movement factor) is to increase the dependence of somatosensory on spatial orientation.
With age, vision deteriorates.
Naturally, we cannot rely on vision to perceive space and direction, and we rely more on feeling.
Judgment, this is completely in line with the clinical manifestations
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Figure 4.
Basic demographic characteristics of the 3 subtypes of PPPD.
It seems very frustrating to say that the 3 subtypes have no significant differences in various vestibular function tests, but (with hope again) there are still some Significantly, this may suggest that the characteristics of each subtype of PPPD are not derived from the type and severity of vestibular dysfunction
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 04 It took a lot of effort to summarize and what if I got many negative results? It's okay, the island scholars have set a good example for us, but there will always be a hopeful but
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Although PPPD was born after PPV, SMD, VV, and CSD, it is still an independent disease with 3 exacerbating factors and 3 subtypes
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PPPD is still a new topic and a lot of research is needed to understand it
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A small step for a scholar from an island country is a giant leap for a scholar from the world
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 Reference: Yagi C, Morita Y, Kitazawa M, Yamagishi T, Ohshima S, Izumi S, Takahashi K and Horii A (2021) Subtypes of Persistent Postural-Perceptual Dizziness.
Front.
Neurol.
12:652366.