Burning Fog: Cognitive Impairment in Burning Mouth Syndrome

Abstract

Background: Due to its common association with chronic pain experience, cognitive impairment (CI) has never been evaluated in patients with burning mouth syndrome (BMS). The purpose of this study is to assess the prevalence of CI in patients with BMS and to evaluate its relationship with potential predictors such as pain, mood disorders, blood biomarkers, and white matter changes (WMCs).Methods: A case-control study was conducted by enrolling 40 patients with BMS and an equal number of healthy controls matched for age, gender, and education. Neurocognitive assessment [Mini Mental State Examination (MMSE), Digit Cancellation Test (DCT), the Forward and Backward Digit Span task (FDS and BDS), Corsi Block-Tapping Test (CB-TT), Rey Auditory Verbal Learning Test (RAVLT), Copying Geometric Drawings (CGD), Frontal Assessment Battery (FAB), and Trail Making A and B (TMT-A and TMT-B)], psychological assessment [Hamilton Rating Scale for Depression and Anxiety (HAM-D and HAM-A), Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), and 36-Item Short Form Health Survey (SF-36)], and pain assessment [Visual Analogic Scale (VAS), Total Pain Rating index (T-PRI), Brief Pain Inventory (BPI), and Pain DETECT Questionnaire (PD-Q)] were performed. In addition, blood biomarkers and MRI of the brain were recorded for the detection of Age-Related WMCs (ARWMCs). Descriptive statistics, the Mann-Whitney U-test, the Pearson Chi-Squared test and Spearman's correlation analysis were used.Results: Patients with BMS had impairments in most cognitive domains compared with controls (p < 0.001**) except in RAVLT and CGD. The HAM-D, HAM-A, PSQI, ESS, SF-36, VAS, T-PRI, BPI and PD-Q scores were statistically different between BMS patients and controls (p < 0.001**) the WMCs frequency and ARWMC scores in the right temporal (RT) and left temporal (LT) lobe were higher in patients with BMS (p = 0.023*).Conclusions: Meanwhile, BMS is associated with a higher decline in cognitive functions, particularly attention, working memory, and executive functions, but other functions such as praxis-constructive skills and verbal memory are preserved. The early identification of CI and associated factors may help clinicians to identify patients at risk of developing time-based neurodegenerative disorders, such as Alzheimer's disease (AD) and vascular dementia (VD), for planning the early, comprehensive, and multidisciplinary assessment and treatment.

The use of self‐report questionnaires in an analysis of the multidimensional aspects of pain and a correlation with the psychological profile and quality of life in patients with burning mouth syndrome: A case‐control study

“…In this study, pain was described by all the patients as burning in quality and it was considered the worst symptom by 23 (57%). The most frequent additional symptoms reported by our samples were xerostomia, a change in the tongue morphology and dysgeusia, in line with previous studies 3,33,35 . In addition, the BMS patients suffered from a high pain intensity (VAS: 8–10; BPI intensity: 19.8–30), which deeply interfered, in terms of intensity and quality, in the individual's life activities (BPI interference: 9–32).…”

“…The most frequent additional symptoms reported by our samples were xerostomia, a change in the tongue morphology and dysgeusia, in line with previous studies. 3,33,35 Instead, in this study, from the analysis of the pain quality, the median and IQR of the SF-MPQ assessment was 5 [3-7.25] in the BMS patients, a result considered to be elevated, as compared with the study of Riordain 8 on 32 individuals, who found a median and IQR for the SF-MPQ of 1.0 [0.0-2.0], and with the study of Tu et al 36 on 248 patients, where the mean of the SF-MPQ was 2.58 ± 2.98.…”

White matter hyperintensities in Burning Mouth Syndrome assessed according to the Age-Related White Matter Changes scale

“…Burning Mouth Syndrome is a type of complex chronic neuropathic orofacial pain disorder, frequently associated with emotional and cognitive impairment ( de Souza et al, 2012 ; Canfora et al, 2021 ). It is known that changes involving the brain structure and networks, typical of central neuropathies, play a key role in the aetiopathogenesis of disease ( Khan et al, 2014 ; Wada et al, 2017 ; Kurokawa et al, 2021 ).…”

“…In one of our previous studies, we have demonstrated for the first time that patients with BMS suffer from cognitive decline mainly in attention, working memory and executive functions, showing a higher score on the ARWMCs in the temporal lobes compared with healthy subjects, thereby suggesting a higher percentage of WMHs in this area of the brain in patients affected by BMS ( Canfora et al, 2021 ).…”

“…The sample size, equal to 100 BMS patients and 102 controls, was set by fixing a power test value (1-Beta) at no less than 99%, associated with a significance of no more than 5%. This sample size was calculated using the effect size value of 0.69, measured in a previously published research study regarding the ARWMCs ( Canfora et al, 2021 ). The calculations were computed using the Gpower software (v 3.1.9).…”