The Psychol Med-Tang team explored the electrophysiological characteristics of sleep in 27 neuropsychiatric disorders

Written by Nie Yuru

Responsible editor—Wang Sizhen, Fang Yiyi

Editor—Summer Leaf

Neuropsychiatric diseases are a significant cause of disability and death worldwide, taking a huge toll
on individuals, families and health systems.
Sleep disturbance is a common clinical symptom
in patients with neuropsychiatric disorders.
In the past, sleep disturbances were seen as clinical symptoms
caused by pathological changes in neuropsychiatric disorders.
There is growing evidence of complex interactions and potential bidirectional causal relationships
between sleep disorders and these disorders.
Sleep disorders can predict the development of neuropsychiatric disorders (eg, depression, anxiety, and neurodegeneration) longitudinally, and effective treatment of neuropsychiatric disorders can improve sleep disorder symptoms [1-3].

Therefore, clarifying the relationship between sleep and neuropsychiatric disorders may help to understand the pathological mechanisms of these disorders [4].

Polysomnography (PSG) is the gold standard
for objectively assessing an individual's sleep characteristics.
Exploring the PSG sleep characteristic variables in patients with neuropsychiatric disorders has the potential to reveal the neurobiological mechanisms of specific diseases, as well as the commonalities and differences between different diseases [5].

Recent studies have found that meta-analyses are susceptible to reporting bias, publication bias, residual confounding bias, and other types of issues that may lead to overestimation of the parameters of the data being tested [6].

Such defects can lead to false-positive results [7], which may mask the most important or significant neurobiological features
of a particular disease.
Therefore, we used an umbrella analysis method to assess the strength of the evidence, the precision of the estimates, robustness, and possible bias for changes in nocturnal PSG characteristics for different neuropsychiatric disorders
.

On November 15, 2022, Professor Tang Xiangdong's team from the Sleep Medicine Center of West China Hospital of Sichuan University published a title in Psychological Medicine "Patterns of polysomnography parameters in 27 neuropsychiatric diseases: an umbrella review
.
" In the article, the researchers explored and compared schizophrenia, bipolar disorder, generalized anxiety disorder, depression, obsessive-compulsive disorder, post-traumatic stress disorder, autism spectrum disorder, anorexia nervosa, stroke, epilepsy, Alzheimer's disease, Parkinson's disease, Huntington's disease, migraine, and traumatic brain injury through umbrella analysis27 The macroscopic and microscopic sleep structure patterns of neuropsychiatric diseases differed, and the results showed that different neuropsychiatric diseases had completely different overall changes in
PSG.
The overall pattern of PSG change is an important dimension that reflects the neuropathological characteristics of different neuropsychiatric disorders.

(Further reading: For the relevant research progress of Tang Xiangdong's research group, see the "Logical Neuroscience" report (click to read):.
) Neurosci Biobehav Rev—Tang Xiangdong's team explores the pharmacological and psychotherapeutic efficacy of PTSD nightmares).

The results of the analysis showed that the overall pattern of sleep changes varied widely between different diseases (Figure 1).

Compared to healthy controls, patients with major depressive disorder (MDD) had sleep latency SL), decreased sleep efficiency (SE), increased percentage sleep in NREM stage 1 in patients with narcolepsy, Parkinson's disease Decrease in REM sleep percentage during the REM phase of disease (PD) is evidence
with a highly suggestive level 。 These findings can also be observed in other neuropsychiatric disorders such as post-traumatic stress disorder, schizophrenia, and Huntington's disease, although the level of confidence in the evidence varies
.
This suggests that changes in individual PSG parameters should be considered as cross-diagnostic sleep features for various neuropsychiatric disorders, rather than signature sleep features
for specific diseases.
There is still a lack of strong evidence that any single change in sleep parameters is specific to
a particular disease.
Observing the overall pattern of changes in PSG found that neither disease had the same overall pattern of changes in sleep characteristics (Figure 1), indicating PSG The overall pattern of change characteristic may be a specific marker
to distinguish between different disease diagnoses.

Fig.
1 Change pattern of sleep parameters (standardized mean difference)
in 27 patients with neuropsychiatric diseases.

(Source: Zhang Y et al.
, Psychol Med, 2022).

Fig.
2 Confidence in polysomnography changes for 27 neuropsychiatric disorders
.

(Source: Zhang Y et al.
, Psychol Med, 2022).

Of the 321 pooled analyses, none had a convincing (convincing) PSG differential strength according to the quantitative umbrella analysis criteria (Figure 2)
。 Only seven (2.
2%) analyses were supported by highly suggestive evidence: people with MDD SL increased, SE decreased; Patients with narcolepsy have increased NREM stage 1 sleep percentage, NREM 2 stage sleep percentage, SL and REML (rapid eye movement sleep latency).
) lower; The percentage of REM sleep is reduced
in PD patients.