Cervical muscle stiffness and parasympathetic nervous system improvements for treatment-resistant depression

Takayoshi Matsui; Kazuhiro Hara; Makoto Iwata; Shuntaro Hojo; Nobuyuki Shitara; Yuzo Endo; Hideoki Fukuoka; Masaki Matsui; Hiroshi Kawaguchi

doi:10.1186/s12891-022-05860-2

Cervical muscle stiffness and parasympathetic nervous system improvements for treatment-resistant depression

BMC Musculoskelet Disord. 2022 Oct 11;23(1):907. doi: 10.1186/s12891-022-05860-2.

Authors

Takayoshi Matsui^{1

2}, Kazuhiro Hara², Makoto Iwata¹, Shuntaro Hojo¹, Nobuyuki Shitara¹, Yuzo Endo¹, Hideoki Fukuoka¹, Masaki Matsui², Hiroshi Kawaguchi³

Affiliations

¹ Tokyo Neurological Center, Toranomon 4-1-17, Minato-ku, Tokyo, 105-0001, Japan.
² Matsui Hospital, Kan-nonji 739, Tokyo, Kagawa, 768-0013, Japan.
³ Tokyo Neurological Center, Toranomon 4-1-17, Minato-ku, Tokyo, 105-0001, Japan. kawaguchi0126@gmail.com.

Abstract

Background: Although treatment-resistant depression (TRD) is a major public health problem that increases mortality due to suicides, a considerable percentage of patients do not respond adequately to variable treatments. Patients with TRD sometimes have comorbid cervical stiffness. This observational study aims to examine the association of local modulation of cervical muscles with TRD and to learn the involvement of the parasympathetic nervous system in the underlying mechanism.

Methods: A total of 1103 hospitalized patients with TRD who were resistant to outpatient care were enrolled between May 2006 and October 2021. All patients underwent local modulation of the cervical muscles by physical therapy during hospitalization. The presence or absence of TRD and whole-body disorders, such as headache, dazzling, cervical stiffness, and cardiovascular and gastrointestinal disorders, was determined by the patient's subjectivity using the self-rated medical interview sheet at admission and discharge. Pupil light reflex parameters were also measured at admission and discharge using a binocular infrared pupilometer.

Results: The improvement rate of TRD during hospitalization was 72.1%, and did not differ significantly by sex, age, and hospitalization period. The improvement of TRD showed a strong association with those of cervical stiffness and dazzling, a pupil light reflex disorder (p < 0.001: odds ratios = 12.76 and 6.39, respectively), but not with those of headache or cardiovascular and gastrointestinal disorders (p > 0.05). In the TRD-improved patients, the pupil light reflex parameters representative of the parasympathetic nervous system function ameliorated: pupil diameter decreased, while constriction rate and velocity increased during hospitalization. In contrast, little amelioration of the parameters was seen in the TRD-unimproved patients.

Conclusions: Cervical muscle stiffness may be associated with TRD, possibly through dysfunction of the parasympathetic nervous system.

Trial registration: ID: UMIN000040590. First registration date: 30/05/2020.

Keywords: Cervical muscle; Parasympathetic nervous system; Physical therapy; Treatment-resistant depression (TRD).

Publication types

Observational Study

MeSH terms

Depression*
Headache
Humans
Muscles
Parasympathetic Nervous System
Suicide*