Headache Medicine 2021, 12(1) p-ISSN 2178-7468, e-ISSN 2763-6178

ASAA

DOI: 10.48208/HeadacheMed.2021.7

Headache Medicine

Original

Association between sleep and awake bruxism in patients with migraine

Keryn Sporh Godk

Maria Luiza dos Santos

Marco Antonio Takashi Utiumi

2,3,4

João Guilherme

Bochnia Küster

Luiz Carlos Canalli Filho

Nikolai José Eustátios Kotsifas

Bin Cheng Tan

Eldislei Mioto

Gabriel Eduardo Faria Colombani

Elcio Juliato Piovesan

2,3

Federal University of Paraná, Health Sciences Sector, Curitiba PR, Brazil.

Federal University of Paraná General Hospital, Department of Internal Medicine, Curitiba PR, Brazil.

São José Neurology Clinic, São José dos Pinhais PR, Brazil.

Marcelino Champagnat Hospital, Neurology Service, Curitiba PR, Brazil.

Abstract

Introduction

When migraine undergoes transformation from episodic to chronic form it becomes more disabling due

to the refractoriness in treatment and the emergence of comorbidities, with the establishment of a bidi-

rectional relationship between sleep bruxism and chronic migraine. This study aimed to assess whether

sleep and awake bruxism are more prevalent in chronic migraine when compared to episodic migraine

and also to establish possible clinical correlations with the process of chronication.

Methods

210 patients were allocated to the study, 97 with episodic migraine and 113 with chronic migraine,

who underwent face-to-face interviews with the completion of the scales: specic questionnaire for the

diagnosis of sleep and awake bruxism, PHQ-9 (depression), GAD-7 (anxiety), Epworth Scale (daytime

sleepiness), MIDAS (migraine incapacity) and HIT-6 (impact of headache).

Results

The prevalence of sleep and awake bruxism was similar in patients with episodic versus chronic migraine

(p=0.300 and p=0.238). The correlation of patients with concomitant awake and sleep bruxism and with

high scores on the migraine incapacity (MIDAS) and headache impact (HIT-6) scales was higher among

patients with chronic migraine than in patients with episodic migraine. (p<0.001 and p<0.001).

Conclusion

Sleep and awake bruxism alone are not more prevalent in chronic migraine when compared to epi-

sodic migraine, although bruxism causes greater impact and disability on individuals with chronic

migraine.

Elcio Juliato Piovesan

Rua General Carneiro, 180,

Alto da Glória, Curitiba, Paraná,

Brazil

Federal University of Paraná

General Hospital

Zip-Code: 80060-900

Phone number: +55 41

33601866

piovesan1@hotmail.com

Edited by:

Marcelo Moraes Valença

Keywords:

Sleep bruxism

Awake bruxism

Migraine Disorders

Impact prole of the disease

Depression

Comorbidity

Received: June 28, 2021

Accepted: August 11, 2021

ASAA

Godk KS, Santos ML, Utiumi MAT, Küster JGB, Canalli Filho LC, Kotsifas NJE, Tan BC, Mioto E, Colombani GEF, Piovesan EJ

Association between sleep and awake bruxism in patients with migraine

Introduction

igraine is considered one of the most debilitating pa-

thologies with roughly half of the patients losing func-

tional capacity during migraine attacks in addition to being

associated with a wide spectrum of comorbidities.

In Brazil,

migraine has a prevalence of 15.2% reaching its peak in

the third decade of life and in the female sex (27.1%).

According to its frequency, it can be classied as episodic

(<15 days a month) or chronic (≥15 days a month for at

least 3 months a year).

Migraine is clinically characterized

by a headache with a duration of 4 to 72 hours if left un-

treated, with a unilateral, pulsatile pain pattern of moderate

to severe intensity, aggravated by routine physical activity

and usually associated with nausea, vomiting, photophobia,

phonophobia and allodynia.

The prevalence of the chronic

form of migraine in Brazil is 5.12% being characterized

by a greater impact on the quality of life, more refractori-

ness to prophylactic treatments, greater predisposition to

comorbidities, disability and loss of productivity, and an

increased demand for medical services and hospitalizations

that consequently generate a high socioeconomic cost.

5,6

Bruxism is a frequent disorder with 85% to 90% of the

general population reporting at least one episode of

grinding or clenching their teeth throughout their lives.

Bruxism is dened as a repetitive activity of the masticatory

muscles that is characterized by squeezing or grinding

the teeth and/or pushing or holding the jaw, being

classied according to its circadian phenotype in sleep

bruxism or awake bruxism.

More recently, sleep bruxism

was dened as masticatory muscle activity during sleep,

formed by a rhythmic phase (Phasic Phase) and a non-

rhythmic phase (Tonic Phase). Awake Bruxism is an activity

of the masticatory muscles that occurs during wakefulness,

being characterized by repetitive and prolonged tooth

contact and/or locking or protrusion of the jaw. Both are

not considered movement disorders in healthy individuals.

Self-reported sleep bruxism is 13% in the adult population

and for awake bruxism the prevalence is 22% in adults

and 31% in women and young people.

It is estimated

that one in ve people in the general population have a

clinical overlap between sleep and awake bruxism.

The

presence of bruxism can be associated with environmental

and genetic factors, stress, anxiety, depression, alterations

in the autonomic system, sleep structure, and use of drugs

or medications, and those are in line with the factors and

comorbidities related to migraine.

12,13

The association between migraine and bruxism in adults

has been documented by several studies, although the

causality has not yet been completely elucidated.

study carried out in Brazil in 2013 showed that 74.6% of

participants with chronic migraine also had sleep bruxism.

Canto et al. in 2014 demonstrated that the risk for patients

with the chronic form of migraine to develop sleep bruxism

is 3.12-3.8 times higher thus demonstrating a bidirectional

relationship between those two pathologies. Regarding

episodic migraine no statistically signicant results were

evidenced.

The inuence of sleep or awake bruxism in the evolution

process of episodic to chronic migraine is not well reported

in the literature. This study aimed to assess whether sleep

and awake bruxism are more prevalent in chronic migraine

when compared to episodic migraine and also to establish

possible clinical correlations with chronication.

Methods

Study design

A comparative cross-sectional observational study between

episodic migraine (EM) and chronic migraine (CM) was

carried out, and individuals of both sexes aged between

18 and 64 years participated. Diagnosis of EM and CM

was dened according to the criteria of the International

Classication of Headache Disorders 3rd edition (ICHD-3).

Patients were allocated into groups based on consultations

carried out between 2018 and 2020 and three Brazilian

healthcare centers participated in this research: a tertiary-

level healthcare center that exclusively serves the public

health system (Federal University of Paraná General

Hospital) and two headache outpatient clinics (São José

Neurology Clinic and Marcelino Champagnat Hospital).

Ethical aspects

This study was approved by the Ethics Committee of the

Federal University of Paraná General Hospital (registration

2.732.610, CAAE number: 87998518.8.0000.0096)

and was registered in the Brazilian Registry of Clinical

Trials (RBR-9wgwnj). Written Informed Consent was

obtained from all the patients prior to data collection.

Study design and population characteristics

Subjects allocated to study participation should meet the

following criteria: (1) Present a denitive diagnosis of EM

or CM (with or without analgesic abuse) in accordance

with the ICHD-3 criteria; (2) Had migraine attacks within

a minimum period of six months at the beginning of the

ASAA

Godk KS, Santos ML, Utiumi MAT, Küster JGB, Canalli Filho LC, Kotsifas NJE, Tan BC, Mioto E, Colombani GEF, Piovesan EJ

Association between sleep and awake bruxism in patients with migraine

study; (3) Had no limitations in information retrieval (e.g.,

severe aphasia, severe hearing loss, or other situations that

could limit the understanding of the questionnaire applied);

(4) Had no associated conditions that could promote

diagnostic confusion (e.g., HIV infections, active cancer,

use of immunosuppressive drugs); (5) Completed all

medical questionnaires; and (6) Agreed to participate in

the study by signing the Written Informed Consent form. All

subjects included in the study received a clinical diagnosis

of EM or CM after a face-to-face medical consultation with

a neurologist with experience in the area of headache

(authors MATU and EJP). The exclusion criteria were: (1)

Withdrawal by the participant of the consent to participate

in the study; and (2) The development of any other type of

headache during the research interval.

Weekly alcohol consumption was classied as: (1) Present;

or (2) Absent. The aerobic physical activity classication

was in accordance with the World Health Organization

recommendations: (1) ≥150 minutes of moderate intensity

or (2) ≥75 minutes of vigorous intensity per week were

considerated as adequate physical activity and the rest

was considered as (3) sedentary.

Monthly income was

calculated to assess the socioeconomic inuence on the

results. The monthly earnings of all family members were

added and divided by the number of individuals residing

in the family group. For years with migraine disease, the

period between the rst migraine attack and the time of

study evaluation was considered.

Data collection, instruments and methods used

To assess depression, anxiety and daytime sleepiness, the

following scales were respectively used: PHQ-9 (Patient

Health Questionnaire-9)

; GAD-7 (Generalized Anxiety

Disorder-7)

and Epworth scale.

MIDAS (Migraine

Disability Assessment Test)

and HIT-6 (Headache Impact

Test)

scales were also included to assess, respectively,

migraine disability and headache impact in study subjects.

Identification of awake and sleep bruxism

To establish the diagnosis of sleep bruxism, a questionnaire

consisting of seven questions prepared by the American

Academy for Sleep Disorders was used

: (1) “Do you

grind or clench your teeth during sleep?”; (2) “When you

wake up, do you feel pain or fatigue in the muscles of the

face?”; (3) “When you wake up and move your mouth, do

you notice stiffness or blockage in your joint?”; (4) “You feel

discomfort in your teeth when you wake up?”; (5) “Do you

feel a headache in your temples when you wake up?”; (6)

“Has a relative or roommate ever reported that you make

creaking noises while sleeping?”; (7) “In the past three

months, have you had fractured teeth or llings, except

for cavities or leaks?”. Using those questions patients were

evaluated in the last 30 days prior to treatment using a

Likert scale consisting of ve possible answers: never; less

than once a month; between one and three days a month;

between one and three days a week; more than four

days a week. Frequent bruxism was considered when the

individual reported a frequency equal to or greater than

once a week for questions 1 or 6. When the frequency

was less than once a week, but occurring at least once a

month, it was considered as eventual bruxism.

To characterize awake bruxism four questions were applied

following the Oral Behavior Checklist

: (1) “Do you grind

or clench your teeth when you are awake?”; (2) “Do you

press, touch or hold your teeth when not chewing?”; (3)

“Do you hold or tense the muscles without chewing?”; (4)

“Do you press, touch or hold your teeth when you are not

chewing?”. The Likert scale was also applied to quantify

awake bruxism. Awake bruxism was considered as present

when the patient answered questions 1, 2 and/or 3 with

the statement “sometime”.

Directed acyclic graphs

Prior to data analysis, directed acyclic graphs were used to

demonstrate each of our assumptions and for statistical adjustment

(Figures 1A, 1B and 1C). The structured model, based on

information from the literature regarding possible relationships

between bruxism and migraine, included variables considered

relevant for predicting sleep bruxism and CM

25,26

(Figure 1A).

The second model considered anxiety and depression symptoms

as part of a confounding pathway between sleep bruxism and

migraine chronicity (Figure 1B). The third model shows our

assumptions for the effect of wakefulness bruxism as a factor in

the chronicity of migraine (Figure 1C). The directed acyclic graphs

were developed in DAGitty software.

ASAA

Godk KS, Santos ML, Utiumi MAT, Küster JGB, Canalli Filho LC, Kotsifas NJE, Tan BC, Mioto E, Colombani GEF, Piovesan EJ

Association between sleep and awake bruxism in patients with migraine

Figure 1. Figures 1A and 1B: Model 1 and 2 (adjusted) for sleep

bruxism. Figure 1C: Model 3 for awake bruxism. Circles: green

- antecedent factors of bruxism; blue - antecedents of migraine

chronicity; red - factors needing adjustment; light gray: factors

not measured in this study; green with triangle - bruxism; blue

marked with I - chronic migraine; white - selection bias. Arrows:

black - causal relationship; green - effects of bruxism on migraine

chronication; red - confounding pathway that needs adjustment.

Statistical analysis

All statistical analyzes were conducted using R version

4.0.2.16. Shapiro-Wilk test and quantile-quantile graphs

were used to verify normality. Thus, sample data were

summarized as mean ± standard deviation, median

(interquartile range) and count (percentage ratio). A

multivariate logistic regression model was tted according

to each model assumption with the presence of CM as the

dependent variable to calculate the prole's odds ratio

(OR) and likelihood ratio ranges. To assess the model's

t, residual analysis, the ratio between residual deviation

and residual degrees of freedom, the Hosmer and

Lemeshow test, the Osius-Rojek test, the Stukel test and the

inuence analysis were used. Tests were performed with a

signicance level of 0.05 and the listwise exclusion method

was used to deal with missing data.

Results

254 individuals were invited to participate in the study, of

which 212 (83%) agreed. After the interview, two patients

were excluded after presenting a recent headache pattern

different from migraine. Thus, 97 patients (46%) with a

diagnosis of EM and 113 patients (54%) with CM were

included. Of the group of patients with EM, 76 did not

have aura (78%) and 21 had aura (22%). In the CM group

78 patients (69%) had analgesic abuse.

The EM and CM groups did not differ with regards to

age (p=0.187), sex (p=0.746), marital status (p=0.451),

race (p=0.167), routine physical activity (p=0.480), body

mass index (p=0.446), family income (p=0.131) and

smoking (p=0.191). Patients with EM had higher alcohol

consumption than patients with CM (p=0.020). Patients

with CM had a slightly longer duration of disease, but not

signicant (p=0.093). Analgesic abuse was higher in the

CM group (p<0.001). The degree of disability was also

higher in the CM group (MIDAS score) (p<0.001) (Table

1).

Table 1. Descriptive and comparative analysis of general clinical aspects

in the episodic and chronic migraine groups.

Variable Episodic migraine (n=97) Chronic migraine (n=113) p-value

Age (years) 38.21±12.54 40.54±12.67 0.187

Gender: female 88 (91%) 101 (89%) 0.746

Marital status: married 56 (58%) 71 (63%) 0.451

Skin color: white 79 (81%) 83 (73%) 0.167

MIDAS score 20 (39) 57 (73)

<0.001***

Migraine duration (years) 10 (14.75) 13 (18) 0.093

Analgesic abuse 24 (25%) 78 (69%)

<0.001***

Adequate physical

activity†

20 (21%) 19 (17%) 0.480

BMI (kg/m²) 25.32 (6.73) 25.49 (7.43) 0.446

Monthly household income

per resident

(Brazilian real)

2500 (2500) 1500 (1500) 0.131

Current or former smoker 3 (3%) 9 (8%) 0.191

Weekly alcohol

consumption

24 (25%) 14 (12%) 0.02*

All data are summarized as mean ± standard deviation, count (frequency,

%) or median (interquartile ratio) according to the variable type and

distribution. * p<0.050; ** p<0.010; *** p<0.001. † At least 150 minutes

of moderate-intensity or 75 minutes of vigorous-intensity aerobic physical

activity. MIDAS: Migraine Disability Assessment.

The frequency of sleep and awake bruxism was similar

in the EM and CM groups (p=0.300 and p=0.238).

Anxiety and depression scores were higher in the CM

group (p=0.012 and p=0.003, respectively). The daytime

sleepiness score was similar in the EM and CM groups

ASAA

Godk KS, Santos ML, Utiumi MAT, Küster JGB, Canalli Filho LC, Kotsifas NJE, Tan BC, Mioto E, Colombani GEF, Piovesan EJ

Association between sleep and awake bruxism in patients with migraine

(Table 2). There was no signicant difference when

comparing the effect of the presence of isolated sleep or

awake bruxism with the absence of bruxism in patients with

CM on the MIDAS and HIT-6 scores (Table 3).

Table 2. Descriptive and comparative analysis of sleep and awake bruxism

in the episodic and chronic migraine groups.

Variable Episodic migraine (n=97) Chronic migraine (n=113) p-value

Sleep bruxism: absent 30 (31%) 29 (26%) 0.300

Sleep bruxism: eventual 25 (26%) 23 (20%) -

Sleep bruxism: frequent 42 (43%) 61 (54%) -

Awake bruxism: absent 33 (34%) 39 (35%) 0.238

Awake bruxism: eventual 46 (47%) 43 (38%)

Awake bruxism: frequent 18 (19%) 31 (27%) -

GAD-7 (anxiety) 8 (8) 11 (9)

0.012*

PHQ-9 (depression) 7 (7) 10 (8)

0.003**

Epworth Scale (daytime

sleepiness)

6 (7) 6 (8) 0.807

All data are summarized as count (frequency, %) or median (interquartile

ratio) according to the variable type and distribution. * p<0.050; **

p<0.010; *** p<0.001. GAD-7: Generalized Anxiety Disorder-7. PHQ-9:

Patient Health Questionnaire-9.

When compared with patients with CM without bruxism,

those with both sleep and awake bruxism had a worse

disability measured by MIDAS (p=0.003), whereas the

impact of headache by the HIT-6 scale was similar with or

without bruxism (p=0.210). However, when the HIT-6 scale

was measured at different degrees of impact, a statistically

signicant difference was found (p=0.007).

Among patients with both types of bruxism, 92.4% had

a severe headache impact score, while patients without

bruxism had a percentage of 72.7% (Table 3). For EM the

difference between the MIDAS and HIT-6 scores regarding

the absence and presence of the two types of bruxism

alone or together was not signicant.

When comparing the EM versus CM groups, regarding

the effect of sleep bruxism on MIDAS and HIT-6, no

statistical differences were found (p=0.126 and p=0.310,

respectively). Regarding the effect of awake bruxism

on MIDAS and HIT-6 the results obtained were also not

statistically different (p=0.930 and p=0.220, respectively).

In the association of both bruxisms, it was observed that the

difference was signicant regarding the effect of bruxism

on the MIDAS and HIT-6 scores being more pronounced in

the CM group (p<0.001 and p<0.001) (Table 4).

Table 3. Relationship between MIDAS and HIT-6 scores and sleep bruxism,

awake bruxism and both in the chronic migraine group.

Chronic migraine

With sleep bruxism

Without sleep

bruxism

p-value

MIDAS Grade 1 4 (25%) 5 (22.7%)

0.800

Grade 2 0 2 (9.1%)

Grade 3 2 (12.5%) 2 (9.1%)

Grade 4 10 (62.5%) 13 (59.1%)

Midas score 32,5 (8.75; 122.5) 30 (6.750; 66.5) 0.600

HIT-6 Little or no impact 0 1 (4.5%)

0.740

Moderate impact 1 (6.3%) 4 (18.2%)

Substantial impact 1 (6.3%) 1 (4.5%)

Severe impact 14 (87.5%) 16 (72.7%)

HIT-6 score 66,5 (60.75; 72) 65 (57.25; 68.75) 0.520

With awake bruxism

Without awake

bruxism

MIDAS Grade 1 1 (20%) 5 (22.7%)

0.400

Grade 2 0 2 (9.1%)

Grade 3 2 (40%) 2 (9.1%)

Grade 4 2 (40%) 13 (59.1%)

Midas score 15 (11; 76) 30 (6.75; 66.5) 0.970

HIT-6 Little or no impact 0 1 (4.5%)

Moderate impact 1 (20%) 4 (18.2%)

Substantial impact 0 1 (4.5%)

Severe impact 4 (80%) 16 (72.7%)

HIT-6 score 66 (66; 66) 65 (57.25; 68.75) 1

Both sleep and awake

bruxism

Without bruxism

MIDAS Grade 1 5 (7.6%) 5 (22.7%)

0.060

Grade 2 2 (3%) 2 (9.1%)

Grade 3 4 (6.1%) 2 (9.1%)

Grade 4 55 (83.3%) 13 (59.1%)

Midas score 69 (35; 101) 30 (6.75; 66.5) 0.003**

HIT-6 Little or no impact 0 1 (4.5%)

0.007**

Moderate impact 1 (1.5%) 4 (18.2%)

Substantial impact 4 (6.1%) 1 (4.5%)

Severe impact 61 (92,4%) 16 (72.7%)

HIT-6 score 66 (64; 70) 65 (57.25; 68.75) 0.210

All data are summarized as count (frequency, %) or median (interquartile

ratio) according to the variable type and distribution. * p<0.050; **

p<0.010; *** p<0.001. MIDAS: Migraine Disability Assessment. HIT-6:

Headache Impact Test.

ASAA

Godk KS, Santos ML, Utiumi MAT, Küster JGB, Canalli Filho LC, Kotsifas NJE, Tan BC, Mioto E, Colombani GEF, Piovesan EJ

Association between sleep and awake bruxism in patients with migraine

Table 4. Relationship between MIDAS and HIT-6 scores and sleep bruxism,

awake bruxism and both in episodic migraine versus chronic migraine.

Episodic migraine Chronic migraine

p-value

With sleep bruxism With sleep bruxism

MIDAS

Grade 1 3 (33.3%) 4 (25%)

0.048*

Grade 2 3 (33.3%) 0

Grade 3 1 (11.1%) 2 (12.5%)

Grade 4 2 (22.2%) 10 (62.5%)

Midas score 7 (5; 17) 32,5 (8.75; 122.5) 0.126

HIT-6

Little or no impact 0 0

0.460

Moderate impact 2 (22.2%) 1 (6.3%)

Substantial impact 1 (11.1%) 1 (6.3%)

Severe impact 6 (66.7%) 14 (87.5%)

HIT-6 score 66 (59; 67) 66,5 (60.75; 72) 0.310

With awake bruxism

With awake

bruxism

MIDAS

Grade 1 2 (28.6%) 1 (20%)

Grade 2 1 (14.3%) 0

Grade 3 1 (14.3%) 2 (40%)

Grade 4 3 (42.9%) 2 (40%)

Midas score 15 (6; 37) 15 (11; 76) 0.930

HIT-6

Little or no impact 0 0

Moderate impact 2 (28.6%) 1 (20%)

Substantial impact 1 (14.3%) 0

Severe impact 4 (57.1%) 4 (80%)

HIT-6 score 62 (55; 64) 66 (66; 66) 0.220

Both sleep and awake

bruxism

Both sleep and

awake bruxism

MIDAS

Grade 1 9 (16.7%) 5 (7.6%)

0.002**

Grade 2 7 (13%) 2 (3%)

Grade 3 10 (18.5%) 4 (6.1%)

Grade 4 28 (51.9%) 55 (83.3%)

Midas score 22,5 (10; 58) 69 (35; 101) <0.001***

HIT-6

Little or no impact 3 (5.6%) 0

0.020*

Moderate impact 5 (9.3%) 1 (1.5%)

Substantial impact 6 (11.1%) 4 (6.1%)

Severe impact 40 (74.1%) 61 (92.4%)

HIT-6 score 63 (59.25; 66.75) 66 (64; 70) <0.001***

All data are summarized as count (frequency, %) or median (interquartile

ratio) according to the variable type and distribution. * p<0.050; **

p<0.010; *** p<0.001. MIDAS: Migraine Disability Assessment. HIT-6:

Headache Impact Test.

For patients with both types of bruxism, a difference was

found in the MIDAS classications between patients in

the two groups (EM and CM), and for patients with CM,

83.3% were classied as 4, while for EM this proportion

was of 51.9% (p=0.002). A statistical difference was also

found between the categories of the HIT-6 questionnaire,

with the CM group having 92.4% of patients classied as

severe impact, while for patients with EM this proportion

was 74.1% (p=0.020) (Table 4).

Using multivariate logistic regression to estimate the effect

of bruxism on migraine, four scenarios were separated,

according to the adjustment of the variables, but there was

no difference in the prevalence of bruxism between the EM

and CM groups (Table 5).

Table 5. Multivariate logistic regression models for estimating the effect

of bruxism on migraine.

Model Comparison OR 95% CI

Not adjusted Sleep bruxism: absent Ref. -

Sleep bruxism: eventual 0.95 0.440-2.040

Sleep bruxism: frequent 1.50 0.790-2.870

Model 1 Sleep bruxism: absent Ref. -

Sleep bruxism: eventual 1.17 0.520-2.680

Sleep bruxism: frequent 1.50 0.750-3.000

Model 2 Sleep bruxism: absent Ref. -

Sleep bruxism: eventual 1.15 0.500-2.650

Sleep bruxism: frequent 1.35 0.660-2.750

Model 3 Awake bruxism: absent Ref. -

Awake bruxism: eventual 0.77 0.390-1.520

Awake bruxism: frequent 1.33 0.580-3.060

Odds ratio for chronic migraine to cause more bruxism in different models

for those with sleep bruxism (models 1 and 2) and awake bruxism (model

3). Model 1 was adjusted for age, use of preventive medication for migraine

and selection method. Model 2 added adjustments for anxiety and

depression symptoms. Model 3 was adjusted for age, anxiety symptoms,

use of preventive medication for migraine and selection method. OR: Odds

ratio. CI: Condence interval. Ref.: reference level.

Discussion

We have observed in the literature that patients with EM

and CM have an increased prevalence of sleep bruxism

and awake bruxism.

14,16

No previous study aimed to assess

the risk that sleep and/or awake bruxism could cause

in the process of chronication of migraine. However, a

study carried out in Brazil showed that the association of

sleep bruxism with migraine was signicant although only

in the chronic form, with no signicant association in the

episodic form of the disease.

However, data from our

study did not support sleep or awake bruxism as being

more prevalent in CM when compared to EM, which could

indicate that there is no relationship between bruxism

and migraine chronicity. However when sleep and awake

bruxism presented concomitally we observed greater

impact and disability on individuals with CM.

As demonstrated by the results of this study, CM is a

disease with greater debilitating power than the episodic

form. This disease brings together patients from different

groups of individuals, as it has in common a headache

pattern typical of migraine, but at the same time they have

ASAA

Godk KS, Santos ML, Utiumi MAT, Küster JGB, Canalli Filho LC, Kotsifas NJE, Tan BC, Mioto E, Colombani GEF, Piovesan EJ

Association between sleep and awake bruxism in patients with migraine

symptoms that are not related to headache and that can

identied as comorbidities. The CaMEO study was perhaps

one of the most important efforts to identify and classify

patients with CM into different groups based on their other

associated clinical characteristics (comorbidities).

In this

study, according to the group of symptoms (comorbidities),

patients were subdivided into eight classes: Class 1 –

Multimorbidities (several associated comorbidities); Class

2 – Respiratory and Psychiatric Comorbidities; Class 3 –

Respiratory and other pains (eg bromyalgia); Class 4 –

Respiratory; Class 5 – Psychiatric; Class 6 – Cardiovascular;

Class 7 – Pain; Class 8 – Few Comorbidities.

This classication allowed a risk stratication for the

evolution of EM to CM. Thus, patients with Class 1 have

an annual risk of 5.34 times higher to undergo migraine

chronication. On the other hand, patients with only one

comorbidity have a 1.53 times greater risk of suffering

this transformation than migraine individuals without

comorbidities.

In these studies, awake and/or sleep

bruxism were not evaluated as a factor in the evolution of

EM to CM.

Another fact from these studies was that the assessment

of the impact of migraine using the MIDAS scales proved

to be effective as a prognostic factor of chronication,

which when high inuences any of the reported classes of

comorbidities.

27,28

In the present study, it was observed that

individuals with sleep and awake bruxism at the same time

have a higher degree of migraine disability. Given these

data, we can assume that bruxism could collaborate with

the degree of disability in CM.

The disability caused by migraine does not fully explain the

association between the comorbidity classes and the risk of

progression to the chronic form, demonstrating that multiple

comorbidities may play a role in this transformation process

but only a higher degree of disability alone would not justify

the transformation from EM to CM.

There is, therefore,

the need for an aggregating factor of transformation, as

may have been the case with the presence of both types

of bruxism. A 10-point increase in disability (MIDAS) is

believed to have the power to transform EM in CM by 1.11

times, 20 points 1.22 times, and 40 points 1.49 times.

An European study evaluated the correlation of the impact

of headache (HIT-6) with sleep bruxism diagnosed by

polysomnography. It has been shown that the relationship

between sleep bruxism and the impact of headache on the

patient's life is only modest, being altered only in patients

with phasic bruxism and is associated with the moment

of awakening.

In our study, however, we did not nd

signicant relevance of the effect of isolated sleep bruxism

on the degree of impact of headache in patients with EM

and CM. However, there was a positive association of a

higher headache impact score in patients with CM who

had both sleep and awake bruxism. In the literature, there

are no reports of similar studies that trace the relationship

of the impact of headache (HIT-6) with the chronicity of

migraine, as well as whether bruxism would have any

inuence on it. In other words, analyzing these data

together, it is possible to show that patients affected by

both forms of bruxism could have repercussions on the

severity of CM when assessed by the degree of impact of

the headache.

A limitation found in our study was that the diagnosis of

bruxism is only classied as possible, as it was based on

self-report, without clinical evaluation and complementary

tests which are necessary for a probable and denitive

diagnosis.

A healthy control group was also not formed

to be used in the comparisons. Future studies using

longitudinal and controlled methodology would be useful

to elucidate the inuences of sleep and awake bruxism on

both forms of migraine.

Conclusion

In conclusion, sleep or awake bruxism alone are not more

prevalent in CM when compared to EM. We observed,

however, that bruxism causes greater impact and disability

on individuals with CM and thus could participate as a

cofactor in the process of migraine chronication.

Conflict of Interest: There is no conict of interest to declare.

Funding: This study was nanced in part by the Coordenação de

Aperfeiçoamento de Pessoal de Nível Superior – Brazil (CAPES) – Finance

Code 001 (grant number 88887.465414/2019-00). This work was

sponsored by Allergan (grant number PG-2020-10985). The funders had

no role in study design, data collection and analysis, decision to publish, or

preparation of the manuscript.

Authors’ contributions: All authors contributed equally to this work.

Keryn Sporh Godk

https://orcid.org/0000-0003-3231-6061

Maria Luiza dos Santos

https://orcid.org/0000-0001-7745-8739

Marco Antonio Takashi Utiumi

https://orcid.org/0000-0001-5273-6798

João Guilherme Bochnia Küster

https://orcid.org/0000-0002-1828-2726

Luiz Carlos Canalli Filho

https://orcid.org/0000-0001-5438-2823

ASAA

Godk KS, Santos ML, Utiumi MAT, Küster JGB, Canalli Filho LC, Kotsifas NJE, Tan BC, Mioto E, Colombani GEF, Piovesan EJ

Association between sleep and awake bruxism in patients with migraine

Nikolai José Eustátios Kotsifas

https://orcid.org/0000-0003-4735-1812

Bin Cheng Tan

https://orcid.org/0000-0003-0812-7906

Eldislei Mioto

https://orcid.org/0000-0001-5376-9292

Gabriel Eduardo Faria Colombani

https://orcid.org/0000-0003-2774-5152

Elcio Juliato Piovesan

https://orcid.org/0000-0002-0915-0430

References

1. Brandes JL. Migraine and functional impairment.

CNS Drugs

2009;23(12):1039-1045 Doi:

10.2165/11530030-000000000-00000

2. Queiroz LP, Peres MF, Piovesan EJ, Kowacs F, Ciciarelli

MC, Souza JA and Zukerman E. A nationwide population-

based study of migraine in Brazil.

Cephalalgia

2009;29(6):642-649 Doi: 10.1111/j.1468-

2982.2008.01782.x

3. Headache Classication Committee of the International

Headache Society (IHS) The International Classification

of Headache Disorders, 3rd edition.

Cephalalgia

2018;38(1):1-211 Doi: 10.1177/0333102417738202

4. Ribeiro FAM, Anderle F, Grassi V, Barea LM, Stelzer FG

and Reppold CRJRBdNeP. Avaliação Neuropsicológica

em Pacientes com Enxaqueca Episódica e Enxaqueca

Crônica/Cefaleia Associada ao uso Excessivo de

Analgésicos. 2017;21(1):17-32

5. Giacomozzi AR, Vindas AP, Silva AA, Jr., Bordini

CA, Buonanotte CF, Roesler CA, . . . Filho PF. Latin

American consensus on guidelines for chronic migraine

treatment.

Arq Neuropsiquiatr

2013;71(7):478-486

Doi: 10.1590/0004-282x20130066

6. Lantéri-Minet M, Duru G, Mudge M and Cottrell S.

Quality of life impairment, disability and economic

burden associated with chronic daily headache, focusing

on chronic migraine with or without medication overuse:

a systematic review.

Cephalalgia

2011;31(7):837-850

Doi: 10.1177/0333102411398400

7. Sateia MJ. International Classification of Sleep Disorders-

Third Edition.

Chest

2014;146(5):1387-1394 Doi:

10.1378/chest.14-0970

8. Lobbezoo F, Ahlberg J, Raphael KG, Wetselaar P, Glaros

AG, Kato T, . . . Manfredini D. International consensus on

the assessment of bruxism: Report of a work in progress.

J Oral Rehabil

2018;45(11):837-844 Doi: 10.1111/

joor.12663

9. Lobbezoo F, Ahlberg J, Glaros AG, Kato T, Koyano K,

Lavigne GJ, . . . Winocur E. Bruxism defined and graded:

an international consensus.

J Oral Rehabil

2013;40(1):2-

4 Doi: 10.1111/joor.12011

10. Ella B, Ghorayeb I, Burbaud P and Guehl D. Bruxism

in Movement Disorders: A Comprehensive Review.

J Prosthodont

2017;26(7):599-605 Doi: 10.1111/

jopr.12479

11. Lavigne GJ, Khoury S, Abe S, Yamaguchi T and Raphael

K. Bruxism physiology and pathology: an overview

for clinicians.

J Oral Rehabil

2008;35(7):476-494 Doi:

10.1111/j.1365-2842.2008.01881.x

12. Wieckiewicz M, Paradowska-Stolarz A and Wieckiewicz

W. Psychosocial aspects of bruxism: the most paramount

factor influencing teeth grinding.

Biomed Res Int

2014;469187 Doi: 10.1155/2014/469187

13. Manfredini D. The Triangle Bruxism, Pain, and

Psychosocial Factors.

Academic Centre for Dentistry

Amsterdam (ACTA)

, Amsterdam, The Netherlands; 2021

14. Costa AL, D'Abreu A and Cendes F. Temporomandibular

joint internal derangement: association with headache,

joint effusion, bruxism, and joint pain.

J Contemp Dent

Pract

2008;9(6):9-16

15. Fernandes G, Franco AL, Gonçalves DA, Speciali JG,

Bigal ME and Camparis CM. Temporomandibular

disorders, sleep bruxism, and primary headaches are

mutually associated.

J Orofac Pain

2013;27(1):14-20

Doi: 10.11607/jop.921

16. De Luca Canto G, Singh V, Bigal ME, Major PW and

Flores-Mir C. Association between tension-type headache

and migraine with sleep bruxism: a systematic review.

Headache

2014;54(9):1460-1469 Doi: 10.1111/

head.12446

17. Organization WH. Global Recommendations on

Physical Activity for Health. 2010;60p

18. Kroenke K, Spitzer RL and Williams JB. The PHQ-9:

validity of a brief depression severity measure.

J Gen

Intern Med

2001;16(9):606-613 Doi: 10.1046/j.1525-

1497.2001.016009606.x

19. Spitzer RL, Kroenke K, Williams JB and Löwe B. A brief

measure for assessing generalized anxiety disorder: the

GAD-7.

Arch Intern Med

2006;166(10):1092-1097 Doi:

https://www.doi.org/10.1001/archinte.166.10.1092