Schizophrenia associated with thermal dysregulation
has been demonstrated in several studies, as well as being noted in the
observations of clinicians for many years. However, while there is an
abundance of research, many of the results have proven to be contradictory,
in particular regarding the confounding effect of antipsychotic medication.
To this end we will review the evidence concerning abnormal
thermoregulation. Understanding the thermal dysregulation may give us an
insight into the pathogenesis of schizophrenia, and a potential role for
orexins in the disease.
To analyse current experimental literature on thermoregulation
in schizophrenia in medicated and unmedicated patients.
PubMed - searched with MeSH term “schizophrenia”, with additional terms;
“thermoregulation”, “orexin” or “hypocretin”.
While there may be disagreements in various studies, the weight of
the early evidence points to untreated schizophrenic patients having lower
baseline core temperatures, while later studies with neuroleptics showed an
increase. Several studies also showed an impaired heat loss in
schizophrenic patients, both in medicated and unmedicated patients.
Meanwhile, orexins have been linked to heat production and heat loss during
sleep. There are also studies showing that orexins are activated by
antipsychotics, and also project to thalamic nuclei that show reduced
volume and connectivity in schizophrenia.
The thermal dysregulation seen in schizophrenia is a complex
process, and the underlying pathogenesis remains to be uncovered. This
mechanism may involve orexins, which may also play a part in both the
pathogenesis of schizophrenia and the relief of symptoms by antipsychotics.