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Pain perception in schizophrenia: influence of neuropeptides, cognitive disorders, and negative symptoms.

Urban-Kowalczyk M, Pigońska J, Śmigielski J - Neuropsychiatr Dis Treat (2015)

Bottom Line: There were no differences in RTIII among study groups.Strong negative correlation (P<0.001) was found between PANSS N scores and subjective pain threshold on the right lower limb.Increase in β-endorphin level may be related to this issue, but it is uncertain if such concentration ensures analgesic effect.

View Article: PubMed Central - PubMed

Affiliation: Department of Affective and Psychotic Disorders, Medical University of Łódź, Łódź, Poland.

ABSTRACT

Objectives: The causes and nature of insensitivity to pain in schizophrenia remain unknown. The role of endorphins and the association of cognitive dysfunction and negative symptoms are postulated.

Methods: In this study, 43 patients with schizophrenia, five first-degree relatives, and 34 healthy controls were examined. Participants' plasma concentrations of substance P, β-endorphin, and calcitonin gene-related peptide (CGRP) were assessed. In patients, the Trail-Making Test, the Color Reading Interference Test (Stroop test), and the Positive and Negative Syndrome Scale Negative Syndrome subscale (PANSS N) test were performed. We also evaluated pain threshold using nociceptive reflex (RTIII) testing.

Results: The mean β-endorphin concentration was about 20% higher in patients than in healthy controls (P<0.05). CGRP concentrations were significantly higher in patients than in controls (5.34 ng/mL versus 4.16 ng/mL; P<0.01). Subjects treated with antipsychotic polytherapy had higher concentrations of CGRP than did patients treated with second-generation antipsychotic monotherapy (5.92 ng/mL versus 5.02 ng/mL; P<0.05). There were no correlations between any biochemical parameters and Trail-Making Test, Stroop test, and PANSS N scores. There were no differences in RTIII among study groups. Strong negative correlation (P<0.001) was found between PANSS N scores and subjective pain threshold on the right lower limb.

Conclusion: The insensitivity to pain in schizophrenia is a complex phenomenon that is probably not related to changes in nociceptive pathways. Increase in β-endorphin level may be related to this issue, but it is uncertain if such concentration ensures analgesic effect. It is unknown if patients with schizophrenia in fact experience less pain. Cognitive impairment and excess negative symptoms may strongly influence the patient's expression of pain.

No MeSH data available.


Related in: MedlinePlus

Comparison of β-endorphin concentrations in test groups.Notes: Patients with schizophrenia had about 20% (P<0.05) higher β-endorphin plasma concentrations than did healthy controls and patients’ relatives. Statistical analysis: analysis of variance rank test, Mann–Whitney test.
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f1-ndt-11-2023: Comparison of β-endorphin concentrations in test groups.Notes: Patients with schizophrenia had about 20% (P<0.05) higher β-endorphin plasma concentrations than did healthy controls and patients’ relatives. Statistical analysis: analysis of variance rank test, Mann–Whitney test.

Mentions: Twenty-eight patients with schizophrenia were treated with second-generation antipsychotics (SGAs) in monotherapy, and 15 patients were treated with polytherapy (SGA + first-generation antipsychotic). The mean PANSS N score in patients was 23.56 (minimum score 16, maximum score 30; standard deviation =4.49). The mean concentration of β-endorphin was significantly higher in patients than in healthy controls and in first-degree relatives (27.59±11.2 pmol/L versus 22.16±6.44 pmol/L and 21.44±8.24 pmol/L, respectively; P<0.05) (Figure 1). There were no statistically significant differences in β-endorphin concentrations between healthy control and relatives.


Pain perception in schizophrenia: influence of neuropeptides, cognitive disorders, and negative symptoms.

Urban-Kowalczyk M, Pigońska J, Śmigielski J - Neuropsychiatr Dis Treat (2015)

Comparison of β-endorphin concentrations in test groups.Notes: Patients with schizophrenia had about 20% (P<0.05) higher β-endorphin plasma concentrations than did healthy controls and patients’ relatives. Statistical analysis: analysis of variance rank test, Mann–Whitney test.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4532169&req=5

f1-ndt-11-2023: Comparison of β-endorphin concentrations in test groups.Notes: Patients with schizophrenia had about 20% (P<0.05) higher β-endorphin plasma concentrations than did healthy controls and patients’ relatives. Statistical analysis: analysis of variance rank test, Mann–Whitney test.
Mentions: Twenty-eight patients with schizophrenia were treated with second-generation antipsychotics (SGAs) in monotherapy, and 15 patients were treated with polytherapy (SGA + first-generation antipsychotic). The mean PANSS N score in patients was 23.56 (minimum score 16, maximum score 30; standard deviation =4.49). The mean concentration of β-endorphin was significantly higher in patients than in healthy controls and in first-degree relatives (27.59±11.2 pmol/L versus 22.16±6.44 pmol/L and 21.44±8.24 pmol/L, respectively; P<0.05) (Figure 1). There were no statistically significant differences in β-endorphin concentrations between healthy control and relatives.

Bottom Line: There were no differences in RTIII among study groups.Strong negative correlation (P<0.001) was found between PANSS N scores and subjective pain threshold on the right lower limb.Increase in β-endorphin level may be related to this issue, but it is uncertain if such concentration ensures analgesic effect.

View Article: PubMed Central - PubMed

Affiliation: Department of Affective and Psychotic Disorders, Medical University of Łódź, Łódź, Poland.

ABSTRACT

Objectives: The causes and nature of insensitivity to pain in schizophrenia remain unknown. The role of endorphins and the association of cognitive dysfunction and negative symptoms are postulated.

Methods: In this study, 43 patients with schizophrenia, five first-degree relatives, and 34 healthy controls were examined. Participants' plasma concentrations of substance P, β-endorphin, and calcitonin gene-related peptide (CGRP) were assessed. In patients, the Trail-Making Test, the Color Reading Interference Test (Stroop test), and the Positive and Negative Syndrome Scale Negative Syndrome subscale (PANSS N) test were performed. We also evaluated pain threshold using nociceptive reflex (RTIII) testing.

Results: The mean β-endorphin concentration was about 20% higher in patients than in healthy controls (P<0.05). CGRP concentrations were significantly higher in patients than in controls (5.34 ng/mL versus 4.16 ng/mL; P<0.01). Subjects treated with antipsychotic polytherapy had higher concentrations of CGRP than did patients treated with second-generation antipsychotic monotherapy (5.92 ng/mL versus 5.02 ng/mL; P<0.05). There were no correlations between any biochemical parameters and Trail-Making Test, Stroop test, and PANSS N scores. There were no differences in RTIII among study groups. Strong negative correlation (P<0.001) was found between PANSS N scores and subjective pain threshold on the right lower limb.

Conclusion: The insensitivity to pain in schizophrenia is a complex phenomenon that is probably not related to changes in nociceptive pathways. Increase in β-endorphin level may be related to this issue, but it is uncertain if such concentration ensures analgesic effect. It is unknown if patients with schizophrenia in fact experience less pain. Cognitive impairment and excess negative symptoms may strongly influence the patient's expression of pain.

No MeSH data available.


Related in: MedlinePlus