Abstract
Objective This study was aimed to investigate the effects of microvascular decompression (MVD) on sleep disorders and obsessions in trigeminal neuralgia.
Methods Clinical data from 115 patients with trigeminal neuralgia treated with MVD from August 1, 2017 to May 31, 2018 at Jining First People's Hospital were analyzed retrospectively. The preoperative and postoperative risk factors for sleep disorders and obsessions, as well as the effects of MVD on sleep disorders and obsessions, were examined.
Results In 115 patients, there were significant differences in preoperative sleep disorders associated with sex, monthly household income, pain in multiple branches, visual analog scale (VAS) score, and Self-Rating Depression Scale (SDS) score ( p < 0.05). Preoperative obsessions were significantly different according to age, gender, pain in multiple branches, monthly household income, VAS score, and Self-Rating Anxiety Scale (SAS) score groups ( p < 0.05). A 1-year recurrence was positively correlated with sleep disturbance (odds ratio = 3.829) and obsessions (odds ratio = 4.507). In addition, the results revealed a negative correlation between the manipulation of trigeminal neuralgia and postoperative sleep disorders ( B ≥ 1.043). Moreover, there was a significant difference in sleep disorders and obsessions before and 1 year after MVD ( p < 0.05).
Conclusion For patients with trigeminal neuralgia, pain caused by sleep and obsession disorders should be examined early to identify an effective solution. Moreover, MVD, as a first treatment, is valuable for improving the physiological and psychological prognosis of patients.
Keywords: trigeminal neuralgia, microvascular decompression, sleep disorders, obsessions
Introduction
Trigeminal neuralgia is a cranial nerve disease involving severe, transient, repetitive, and electric shock-like pain in single or multiple branches of the trigeminal nerve. 1 However, the pathogenesis of the disease is currently contentious. The theory of neurovascular compression is one of the most widely accepted explanations, 2 and microvascular decompression (MVD) is considered as one of the most effective treatments for the disorder. 3 This surgical method has been well studied, and thousands of patients with trigeminal neuralgia have benefitted from it. 4
Although trigeminal neuralgia is a relatively common disease, and the prognosis is usually excellent, the severe pain caused by trigeminal neuralgia can seriously impact patients' quality of life. 5 It has been reported that anxiety and depression in patients with trigeminal neuralgia are worse than in patients with atypical facial pain. 6 Moreover, long-term chronic pain can lead to psychological problems, such as poor sleep quality and obsessive-compulsive symptoms. 7 In recent years, several studies have focused on the treatment of MVD and surgical techniques, while few studies have examined the psychological problems associated with the disease. In addition, the diagnosis and treatment of comorbid mental illnesses caused by this painful disorder have often been neglected in developing countries, for various cultural and economic reasons. 8
Research into the mental disorders associated with trigeminal neuralgia may be valuable for improving medical services and prognosis for patients with trigeminal neuralgia. This notion conforms to the modern medical conception of the relationships between “biology, psychology, and society.” 9 To address this issue, we searched for relevant literature published in the PubMed database, and conducted a prospective study of sleep disorders and obsessions among patients with trigeminal neuralgia to determine the risk factors and curative effects of MVD on these psychological problems.
Methods
Study Subjects
We selected 152 patients with trigeminal neuralgia who underwent MVD at the Department of Neurosurgery of the First People's Hospital of Jining City in Shandong Province from August 1, 2017 to May 31, 2018. All of the patients met the diagnostic criteria for primary trigeminal neuralgia in the Chinese expert consultation on microvascular decompression for trigeminal neuralgia and glossopharyngeal neuralgia. The inclusion criteria included the following: (1) pain limited to the trigeminal sensory root distribution area, with a clear remission period; (2) obvious inducing factors or trigger points; (3) received a sigmoid sinus approach for trigeminal MVD treatment; (4) initially responded effectively to carbamazepine; and (5) cooperation with a follow-up survey. The exclusion criteria included the following: (1) age below 30 or over 85 years; (2) carbamazepine was ineffective; (3) confirmed presence of tumors, vascular malformations, and other secondary pathological factors; (4) history of mental illness or cognitive impairment in the past; and (5) lost during follow-up. All patients voluntarily participated in the study and signed the informed consent. This study was approved by the Jining City Ethics Committee.
Scoring Scale
Visual analogue scale/score (VAS) 10 : the VAS used a 10-cm horizontal line to indicate different degrees of pain, and patients were instructed to indicate their pain on the line based on the severity of the pain. Scores of 1 to 3 points indicated mild pain, 4 to 7 points indicated moderate pain, and 8 to 10 points indicated severe pain.
The self-rating depression scale (SDS) 11 : the SDS included 20 items, divided into four grades of self-rating scale. The scale included two items of mental-emotional symptoms, eight items of somatic disorders, two items of psychomotor disorders and eight items of depressive psychological disorders. The SDS is generally considered appropriate for adults with depressive symptoms of varying degrees. An SDS standard score ≥ 53 indicates a positive classification for depression. In addition, patients with scores of 53 to 62 points and 63 to 72 points were divided into mild depression and moderate depression groups, respectively. Patients with scores greater than 73 points were considered to have severe depression.
Self-rating anxiety scale (SAS) 12 : the SAS uses a four-level rating scale to assess the frequency of symptoms defined by the items. This scale is suitable for adults with anxiety symptoms and has similarly broad applicability to the SDS. An SAS standard score ≥ 50 indicates anxiety status, with higher scores indicating more severe anxiety.
Pittsburgh sleep quality index (PSQI) 13 : The PSQI is a 19-item questionnaire based on the patient's sleep quality in the last month, and it is suitable for patients with sleep disorders, mental disorders, and healthy individuals for assessing sleep quality. Scores of 0 to 5 points for sleep quality are considered healthy, while scores of 6 points or more indicate sleep impairment.
The Yale–Brown obsessive-compulsive scale (Y-BOCS) 14 : the Y-BOCS survey questionnaire is divided into obsessions and compulsions, and is used for measuring the severity of obsessive-compulsive symptoms in clinical settings. The total Y-BOCS score is 40 points, and each part has 20 points. A score of simple obsessiveness ≥6 indicates that the symptom of obsessive thought is positive. In addition, scores of 6 to 9 points are considered to indicate mild obsessions, scores of 10 to 14 points indicate obsessions of moderate severity, and scores of 15 to 20 points indicate the most severe level of obsessions.
Data Collection
All 152 patients received statistics of general clinical features (such as age, sex, branch of pain, side, and other conditions; details in Tables 1 2 3 4 ) and the above-mentioned scoring scale surveys (VAS, SDS, SAS, PSQI, and Y-BOCS) on the day of admission immediately. Participants then underwent a standard retrosigmoid approach to trigeminal nerve MVD under general anesthesia after preoperative preparation. We recorded the recovery and intraoperative situation (condition of intraoperative relevant vessels, manipulation of trigeminal nerve; details in Tables 5 6 7 8 ), postoperative complications, and recurrence of the patients over time after MVD. All patients were followed-up 1 year strictly, after discharge, by telephone. The error of follow-up time does not exceed 3 days (If it is exceeded, we will exclude this case).We collected and recorded these data using the same method described above. All researchers were professionally trained. However, there were 37 patients with a series of problems of lost to follow-up, answering the questions perfunctorily or refusing to follow-up among 152 patients. Finally, a total of 115 patients were included in the statistical analysis.
Table 1. Analysis of preoperative PSQI Chi-square test in patients with trigeminal neuralgia.
| Characteristics | No. (%) | Preoperative PSQI | χ 2 /T | p -Value | ||
|---|---|---|---|---|---|---|
| ≤5 (%) | >5 (%) | |||||
| Sex | Male | 58 (50.4) | 21 (67.7) | 37 (44) | 5.085 | 0.024 |
| Female | 57 (49.6) | 10 (32.3) | 47 (56) | |||
| Age (y) | ≤40 | 4 (3.5) | 3 (9.7) | 1 (1.2) | 5.353 | 0.069 |
| 41–60 | 42 (36.5) | 9 (29) | 33 (39.3) | |||
| ≥61 | 69 (60) | 19 (61.3) | 50 (59.5) | |||
| Side of pain | Left | 52 (45.2) | 14 (45.2) | 38 (45.2) | 0.000 | 0.994 |
| Right | 63 (54.8) | 17 (54.8) | 46 (54.8) | |||
| Distribution of pain a | Single branch | 68 (59.1) | 21 (67.7) | 47 (56) | 1.302 | 0.254 |
| More than 1 branch | 47 (40.9) | 10 (32.3) | 37 (44) | |||
| Medical history time (mo) | ≤3 | 12 (10.4) | 4 (12.9) | 8 (9.5) | 0.287 | 0.866 |
| 3–12 | 12 (10.4) | 3 (9.7) | 9 (10.7) | |||
| ≥12 | 91 (79.1) | 24 (77.4) | 67 (79.8) | |||
| Marital status | Married | 114 (99.1) | 30 (96.8) | 84 (100) | 2.733 | 0.098 |
| Single | 1 (0.9) | 1 (3.2) | 0 (0) | |||
| Education level (y) | <9 | 66 (57.4) | 15 (48.4) | 51 (60.7) | 1.407 | 0.236 |
| ≥9 | 49 (42.6) | 16 (51.6) | 33 (39.3) | |||
| Monthly income (Yuan) | ≤3,000 | 26 (22.6) | 5 (16.1) | 21 (25) | 10.911 | 0.004 |
| 3,001–5000 | 56 (48.7) | 10 (32.3) | 46 (54.8) | |||
| ≥5,001 | 33 (28.7) | 16 (51.6) | 17 (20.2) | |||
| Employment status | Employed (including retired) | 35 (30.4) | 13 (41.9) | 22 (26.2) | 2.651 | 0.103 |
| Unemployed | 80 (69.6) | 18 (58.1) | 62 (73.8) | |||
| Alcohol and tobacco hobbies | No | 86 (74.8) | 22 (71) | 64 (76.2) | 0.328 | 0.567 |
| Yes | 29 (25.2) | 9 (29) | 20 (23.8) | |||
| BMI (kg/m 2 ) | Standard b | 94 (81.7) | 28 (90.3) | 66 (78.6) | 2.095 | 0.148 |
| Not standard c | 21 (18.3) | 3 (9.7) | 18 (21.4) | |||
| Prehospital treatment | No | 27 (23.5) | 8 (25.8) | 19 (22.6) | 2.975 | 0.226 |
| Other treatments (not including tooth extraction treatment) | 62 (53.9) | 13 (41.9) | 49 (58.3) | |||
| Tooth extraction treatment | 26 (22.6) | 10 (32.3) | 16 (19) | |||
| Other chronic diseases | No | 45 (39.1) | 12 (38.7) | 33 (39.3) | 0.003 | 0.955 |
| Yes | 70 (60.9) | 19 (61.3) | 51 (60.7) | |||
| VAS scores | 2–7 | 65 (56.5) | 2 4(77.4) | 41 (48.8) | 7.542 | 0.006 |
| 8–10 | 50 (43.5) | 7 (22.6) | 43 (51.2) | |||
| SDS scores | <53 | 43 (37.4) | 18 (58.1) | 25 (29.8) | 7.748 | 0.005 |
| ≥53 | 72 (62.6) | 13 (41.9) | 59 (70.2) | |||
| SAS scores | <50 | 43 (37.4) | 13 (41.9) | 30 (35.7) | 0.374 | 0.541 |
| ≥50 | 72 (62.6) | 18 (58.1) | 54 (64.3) | |||
Abbreviations: BMI, body mass index; PSQI, Pittsburgh Sleep Quality Index; SAS, self-rating anxiety scale; SDS, self-rating depression scale; VAS, visual analog scale.
“Distribution of Pain” represents distribution area accumulated by trigeminal neuralgia, including six branches(take the sagittal line as the center, the left and right face each occupy three branches). To explore the correlation between extent of pain and the subject of our study, we divide the distribution of pain into “single branch” and “more than 1 branch.”
“Standard” represents a BMI value between “18.5” to “24.9,” which means moderate obesity.
“Not standard” represents a BMI < 18.5 or > 24.9, which mean being thin or overweight.
Table 2. Logical regression analysis of preoperative PSQI in patients with trigeminal neuralgia.
| Factors | B a | SE b | OR c | DF d | Sig e |
|---|---|---|---|---|---|
| Sex | 1.521 | 0.628 | 4.579 | 1 | 0.015 |
| Age (y) | 0.230 | 0.498 | 1.259 | 1 | 0.643 |
| Side of pain | 0.421 | 0.578 | 1.523 | 1 | 0.467 |
| Distribution of pain | 1.355 | 0.650 | 3.876 | 1 | 0.037 |
| Medical history time (mo) | −0.341 | 0.437 | 0.711 | 1 | 0.436 |
| Marital status | −24.836 | 40,192.980 | 0.000 | 1 | 1.000 |
| Education level | −0.555 | 0.602 | 0.574 | 1 | 0.356 |
| Monthly income (Yuan) | −1.244 | 0.487 | 0.288 | 1 | 0.011 |
| Employment status | 0.380 | 0.623 | 1.462 | 1 | 0.542 |
| Alcohol and tobacco hobbies | −0.343 | 0.691 | 0.710 | 1 | 0.620 |
| BMI (kg/m 2 ) | 1.463 | 0.980 | 4.319 | 1 | 0.136 |
| Prehospital treatment | −0.673 | 0.421 | 0.510 | 1 | 0.110 |
| Other chronic diseases | −0.609 | 0.594 | 0.544 | 1 | 0.305 |
| VAS scores | 0.584 | 0.616 | 1.793 | 1 | 0.343 |
| SDS scores | 1.365 | 0.568 | 3.916 | 1 | 0.016 |
| SAS scores | −0.217 | 0.588 | 0.805 | 1 | 0.712 |
| Constant | 23.066 | 40,192.980 | 10,412,026,635.95 | 1 | 1.000 |
Abbreviations: BMI, body mass index; PSQI, Pittsburgh Sleep Quality Index; SAS, self-rating anxiety scale; SDS, self-rating depression scale; VAS, visual analog scale.
“B” represents regression coefficient.
“SE” represents standard error.
“OR” represents adjusted odds ratio.
“dF” represents degree of freedom.
“Sig” represents p -value.
Table 3. Analysis of preoperative Y-BOCS obsessions Chi-square test in patients with trigeminal neuralgia.
| Characteristics | No. (%) | Preoperative Y-BOCS obsessions | χ 2 | p -Value | ||
|---|---|---|---|---|---|---|
| <6 (%) | ≥6 (%) | |||||
| Sex | Male | 58 (50.4) | 17 (63) | 41 (46.6) | 2.215 | 0.137 |
| Female | 57 (49.6) | 10 (37) | 47 (53.4) | |||
| Age (y) | ≤40 | 4 (3.5) | 3 (11.1) | 1 (1.1) | 6.124 | 0.047 |
| 41–60 | 42 (36.5) | 9 (33.3) | 33 (37.5) | |||
| ≥61 | 69 (60) | 15 (55.6) | 54 (61.4) | |||
| Side of pain | Left | 52 (45.2) | 12 (44.4) | 40 (45.5) | 0.009 | 0.926 |
| Right | 63 (54.8) | 15 (55.6) | 48 (54.5) | |||
| Distribution of pain | Single branch | 68 (59.1) | 20 (74.1) | 48 (54.5) | 3.260 | 0.071 |
| More than one branch | 47 (40.9) | 7 (25.9) | 40 (45.5) | |||
| Medical history time (mo) | ≤3 | 12 (10.4) | 2 (7.4) | 10 (11.4) | 0.783 | 0.676 |
| 3–12 | 12 (10.4) | 2 (7.4) | 10 (11.4) | |||
| ≥12 | 91 (79.1) | 23 (85.2) | 68 (77.3) | |||
| Marital status | Married | 114 (99.1) | 26 (96.3) | 88 (100) | 3.288 | 0.070 |
| Single | 1 (0.9) | 1 (3.7) | 0 (0) | |||
| Education level (y) | <9 | 66 (57.4) | 13 (48.1) | 53 (60.2) | 1.233 | 0.267 |
| ≥9 | 49 (42.6) | 14 (51.9) | 35 (39.8) | |||
| Monthly income (Yuan) | ≤3,000 | 26 (22.6) | 4 (14.8) | 22 (25) | 2.863 | 0.239 |
| 3,001–5,000 | 56 (48.7) | 12 (44.4) | 44 (50) | |||
| ≥5001 | 33 (28.7) | 11 (40.7) | 22 (25) | |||
| Employment status | Employed (including retired) | 35 (30.4) | 8 (29.6) | 27 (30.7) | 0.011 | 0.917 |
| Unemployed | 80 (69.6) | 19 (70.4) | 61 (69.3) | |||
| Alcohol and tobacco hobbies | No | 86 (74.8) | 22 (81.5) | 64 (72.7) | 0.840 | 0.360 |
| Yes | 29 (25.2) | 5 (18.5) | 24 (27.3) | |||
| BMI (kg/m 2 ) | Standard | 94 (81.7) | 22 (81.5) | 72 (81.8) | 0.002 | 0.968 |
| Not standard | 21 (18.3) | 5 (18.5) | 16 (18.2) | |||
| Prehospital treatment | No | 27 (23.5) | 4 (14.8) | 23 (26.1) | 2.951 | 0.229 |
| Other treatments(not including tooth extraction treatment) | 62 (53.9) | 14 (51.9) | 48 (54.5) | |||
| Tooth extraction treatment | 26 (22.6) | 9 (33.3) | 17 (19.3) | |||
| Other chronic diseases | No | 45 (39.1) | 9 (33.3) | 36 (40.9) | 0.498 | 0.480 |
| Yes | 70 (60.9) | 18 (66.7) | 52 (59.1) | |||
| VAS scores | 2–7 | 65 (56.5) | 20 (74.1) | 45 (51.1) | 4.423 | 0.035 |
| 8–10 | 50 (43.5) | 7 (25.9) | 43 (48.9) | |||
| SDS scores | <53 | 43 (37.4) | 12 (44.4) | 31 (35.2) | 0.750 | 0.387 |
| ≥53 | 72 (62.6) | 15 (55.6) | 57 (64.8) | |||
| SAS scores | <50 | 43 (37.4) | 16 (59.3) | 27 (30.7) | 7.208 | 0.007 |
| ≥50 | 72 (62.6) | 11 (40.7) | 61 (69.3) | |||
Abbreviations: BMI, body mass index; SAS, self-rating anxiety scale; SDS, self-rating depression scale; VAS, visual analog scale; Y-BOCS, Yale-Brown obsessive-compulsive scale.
Table 4. Logical regression analysis of preoperative Y-BOCS obsessions in patients with trigeminal neuralgia.
| Factors | B | SE | OR | DF | Sig |
|---|---|---|---|---|---|
| Sex | 1.496 | 0.643 | 4.464 | 1 | 0.020 |
| Age (y) | 0.519 | 0.497 | 1.681 | 1 | 0.296 |
| Side of pain | 0.338 | 0.594 | 1.402 | 1 | 0.570 |
| Distribution of pain | 1.454 | 0.688 | 4.279 | 1 | 0.035 |
| Medical history time (mo) | −0.594 | 0.499 | 0.552 | 1 | 0.234 |
| Marital status | −23.754 | 40,192.970 | 0.000 | 1 | 1.000 |
| Education level | −0.663 | 0.589 | 0.515 | 1 | 0.260 |
| Monthly income (Yuan) | −1.045 | 0.486 | 0.352 | 1 | 0.031 |
| Employment status | −0.532 | 0.687 | 0.587 | 1 | 0.439 |
| Alcohol and tobacco hobbies | 0.481 | 0.732 | 1.618 | 1 | 0.511 |
| BMI (kg/m 2 ) | 0.669 | 0.842 | 1.952 | 1 | 0.427 |
| Prehospital treatment | −0.760 | 0.452 | 0.468 | 1 | 0.093 |
| Other chronic diseases | −0.967 | 0.616 | 0.380 | 1 | 0.116 |
| VAS scores | 0.318 | 0.632 | 1.375 | 1 | 0.615 |
| SDS scores | 0.132 | 0.617 | 1.142 | 1 | 0.830 |
| SAS scores | 1.274 | 0.592 | 3.577 | 1 | 0.031 |
| Constant | 22.805 | 40,192.970 | 8,016,987,482.305 | 1 | 1.000 |
Abbreviations: BMI, body mass index; DF, degree of freedom; OR, odds ratio; SAS, self-rating anxiety scale; SDS, self-rating depression scale; SE, standard error; Sig., p -value; VAS, visual analog scale; Y-BOCS, Yale-Brown obsessive-compulsive scale.
Table 5. Chi-square test analysis of PSQI score in patients with trigeminal neuralgia 1-year after MVD.
| Characteristics | No. (%) | Postoperative PSQI | χ 2 /T | p -Value | ||
|---|---|---|---|---|---|---|
| ≤5 | >5 | |||||
| Intraoperative relevant vessels condition | No blood vessels | 7 (6.1) | 6 (8.2) | 1 (2.4) | 1.664 | 0.435 |
| Single vessel | 78 (67.8) | 49 (67.1) | 29 (69) | |||
| Multiple vessels | 30 (26.1) | 18 (24.7) | 12 (28.6) | |||
| Condition of manipulation of trigeminal nerve a | No manipulation | 90 (78.3) | 53 (72.6) | 37 (88.1) | 5.439 | 0.066 |
| Internal neurolysis | 18 (15.7) | 13 (17.8) | 5 (11.9) | |||
| Partially section the sensory root | 7 (6.1) | 7 (9.6) | 0 (0) | |||
| Complications during 7 days after operation | No | 93 (80.8) | 61 (82.5) | 32 (76.2) | 0.936 | 0.333 |
| Yes | 22 (19.2) | 12 (17.5) | 10 (23.8) | |||
| Recurrence | No | 97 (84.4) | 66 (90.4) | 31 (73.8) | 5.566 | 0.018 |
| Yes | 18 (15.6) | 7 (9.6) | 11 (26.2) | |||
Abbreviation: MVD, microvascular decompression; PSQI, Pittsburgh Sleep Quality Index.
“Condition of manipulation of trigeminal nerve” includes three manipulation methods: no manipulation for the nerve(or simple decompression), internal neurolysis and partially section the sensory root.
Table 6. Logistic regression analysis of sleeping PSQI score in patients with trigeminal neuralgia 1-year after MVD.
| Factors | B | SE | OR | DF | Sig |
|---|---|---|---|---|---|
| Intraoperative relevant vessels condition | 0.271 | 0.423 | 1.312 | 1 | 0.522 |
| Condition of manipulation of trigeminal nerve | −1.043 | 0.513 | 0.352 | 1 | 0.042 |
| Complications during 7 days after operation | −0.215 | 0.508 | 1.240 | 1 | 0.672 |
| Recurrence | 1.343 | 0.562 | 3.829 | 1 | 0.017 |
| Constant | −0.925 | 0.583 | 0.397 | 1 | 0.112 |
Abbreviations: DF, degree of freedom; MVD, microvascular decompression; OR, odds ratio; PSQI, Pittsburgh Sleep Quality Index; SE, standard error; Sig., p -value.
Table 7. Analysis of Y-BOCS obsessions Chi-square test in patients with trigeminal neuralgia 1-year after MVD.
| Characteristics | No. (%) | Postoperative Y-BOCS obsessions | χ 2 | p -Value | ||
|---|---|---|---|---|---|---|
| <6 | ≥6 | |||||
| Intraoperative relevant vessels condition | No blood vessels | 7 (6.1) | 6 (5.9) | 1 (7.7) | 1.345 | 0.510 |
| Single vessel | 78 (67.8) | 71 (69.6) | 7 (53.8) | |||
| Multiple vessels | 30 (26.1) | 25 (24.5) | 5 (38.5) | |||
| Condition of manipulation of trigeminal nerve | No manipulation | 90 (78.3) | 79 (77.5) | 11 (84.6) | 0.968 | 0.616 |
| Internal neurolysis | 18 (15.7) | 16 (15.7) | 2 (15.4) | |||
| Partially section the sensory root | 7 (6.1) | 7 (6.9) | 0 (0) | |||
| Complications during 7 days after operation | No | 93 (80.8) | 84 (82.3) | 9 (69) | 1.283 | 0.257 |
| Yes | 22 (19.2) | 18 (17.7) | 4 (30.7) | |||
| Recurrence | No | 97 (84.4) | 89 (87.3) | 8 (61.5) | 5.776 | 0.016 |
| Yes | 18 (15.6) | 13 (12.7) | 5 (38.5) | |||
Abbreviations: MVD, microvascular decompression; Y-BOCS, Yale–Brown obsessive-compulsive scale.
Table 8. Logistic regression analysis of Y-BOCS obsessions score in patients with trigeminal neuralgia 1-year after MVD.
| Factors | B | SE | OR | DF | Sig |
|---|---|---|---|---|---|
| Intraoperative relevant vessels condition | 0.370 | 0.613 | 1.488 | 1 | 0.546 |
| Condition of manipulation of trigeminal nerve | −0.497 | 0.743 | 0.609 | 1 | 0.504 |
| Complications during 7 days after operation | 0.538 | 0.700 | 1.712 | 1 | 0.442 |
| Recurrence | 1.506 | 0.658 | 4.507 | 1 | 0.022 |
| Constant | −2.904 | 0.897 | 0.055 | 1 | 0.001 |
Abbreviations: DF, degree of freedom; MVD, microvascular decompression; OR, odds ratio; SE, standard error; Sig., p -value; Y-BOCS, Yale–Brown obsessive-compulsive scale.
Statistical Analyses
We used IBM SPSS 22.0 for statistical analysis of the data. The measurement data were expressed as x ± s, and the enumeration data were recorded as frequencies and percentages. We performed a Chi-square test and logistic regression analysis of preoperative and postoperative PSQI (Pittsburgh Sleep Quality Index) and Y-BOCS obsession scores in all patients to identify risk factors. Paired t -tests were used to analyze the preoperative and postoperative PSQI, including Y-BOCS obsession scores. Associations were considered statistically significant when p < 0.05.
Results
General Clinical Characteristics
We grouped 115 patients according to clinical characteristics and research purposes comprising 58 men (50.4%) and 57 women (49.6%) with a mean age of 62.35 ± 10.97 years (range, 32–84 years) in our study. Pain was located on the left side of the face in 52 cases (45.2%) and on the right side of the face in 63 cases (54.8%). 68 patients (59.1%) had pain involving a single branch, and 47 patients (40.9%) had pain involving multiple branches. In 26 cases (22.6%), monthly household income was less than 3,000 (y) income, with 56 patients' (48.7%) income level between 3,000 and 5,000 (y), and 33 (28.7%) patients earned more than 5,000 (y) per month. Other patient characteristics are shown in Table 1 .
Preoperative Situation Regarding Pain, Depression, Anxiety, Sleep Disorders, and Obsessions
Sixty-five patients (56.5%) reported mild or moderate pain and 50 patients (43.5%) reported severe pain. The mean VAS score was 6.76 ± 1.8 (range, 1–10). The numbers of depression-positive and anxiety-positive patients were both 72 (62.6%, SDS score ≥ 53, SAS score ≥ 50). The mean SDS score was 59.52 ± 17.0 (range, 25–100) and SAS score was 52.50 ± 13.3 (range, 25–100).
In the current study, there were 84 patients with sleep disorders (PSQI score > 5) and 88 patients with obsessions (Y-BOCS-obsession score ≥ 6). The mean PSQI score was 9.64 ± 4.94 and the mean Y-BOCS-obsession score was 8.90 ± 5.03.
Risk Factors for Preoperative Sleep Disorders and Obsessions
There were significant differences between PSQI ≤ 5 points and > 5 points groups in sex, monthly household income, preoperative VAS score, and SDS score groups after Chi-square test analysis ( p < 0.05). Logistic regression analysis revealed that sex, pain in multiple branches, monthly household income, and SDS score were related to sleep disorders. The results indicated that the incidence of sleep disorders in females was 4.579 times (odds ratio [OR] = 4.579) higher than that in males. The rate of sleep disorders in patients with pain involving multiple branches was 3.876 times (OR = 3.876) that in patients with pain involving a single branch. Patients with positive depression status had a 3.916 times (OR = 3.916) higher prevalence of sleep disorders compared with patients with no depression, and monthly household income was negatively correlated with sleep disorders ( B = −1.244, in Tables 1 and 2 ).
The different preoperative Y-BOCS obsession score groups had significant differences in sex, VAS, and SAS scores ( p < 0.05) in Chi-square tests. Logistic regression analysis revealed that sex (OR = 4.464), cumulative branches of pain (OR = 4.279), and SAS score (OR = 3.577) exhibited positive correlations with sleep disorders, which were negatively correlated with monthly household income ( B = −1.405, in Tables 3 and 4 ).
Risk Factors for Postoperative Sleep Disorders, Obsessions, and Follow-up
Scores for sleep disorders and obsessions were significantly different between postoperative recurrence in Chi-square tests and logistic regression analysis. Logistic regression analysis revealed that postoperative recurrence was positively correlated with sleep disorders (OR = 3.829) and obsessions (OR = 4.507) in 1-year follow up, while manipulation of the trigeminal nerve was negatively correlated with sleep disorders ( B ≥ 1.043, in Tables 5 6 7 8 ). Moreover, we manipulated the trigeminal nerve in 25 cases (21.8%).
Paired t -test analysis revealed that sleep disorders and obsession scores exhibited a significant downward trend between MVD preoperative score and 1-year follow-up ( p < 0.05). Mean PSQI score decreased from 9.64 ± 4.94 to 4.65 ± 3.51 ( p < 0.05) and mean Y-BOCS obsession score also decreased from 8.90 ± 5.03 to 2.52 ± 3.66 ( p < 0.05, in Table 9 ).
Table 9. Paired t -test analysis of PSQI and Y-BOCS obsessions scores before and 1-year after MVD in patients with trigeminal neuralgia .
| Characteristics | Before MVD | 1-year after MVD | t -Value | p -Value |
|---|---|---|---|---|
| PSQI | 9.64 ± 4.94 | 4.65 ± 3.51 | 9.374 | 0.000 |
| Y-BOCS obsessions | 8.90 ± 5.03 | 2.52 ± 3.66 | 13.166 | 0.000 |
Abbreviations: MVD, microvascular decompression; PSQI, Pittsburgh Sleep Quality Index; Y-BOCS, Yale–Brown obsessive-compulsive scale.
Discussion
Trigeminal neuralgia is a relatively common neurological functional disease in middle-aged and elderly patients. The condition is characterized by unbearable electric shock-like pain distributed in the area of the fifth cranial nerve, resulting in a decline in patients' quality of life. 15 Traditionally, trigeminal neuralgia has been considered a “suicide disease” with a high risk of self-harm. 16 Although a small number of previous studies have reported data regarding patients' psychological problems, this research is relatively limited, particularly in China. With economic development on a global scale, psychological health is receiving increasing attention in hospital settings. Therefore, we investigated sleep disorders and obsessions among 115 patients with trigeminal neuralgia, as well as patients' degree of pain, depression, and anxiety, aiming to elucidate the psychological problems of patients and the effects of MVD.
Regarding sleep disorders, our results indicated that 84 of 115 patients exhibited mild-to-severe sleep disorders. In addition, sleep disorders were more serious in patients with pain involving multiple branches of the trigeminal sensory root, VAS scores of 8 to 10, and/or SAS scores ≥53. These results appear to be related to the pain caused by the disease. According to Table 2 , pain with stronger severity and an extensive pain area is more likely to physiologically affect the patient's dopamine system, and change their sensitivity to pain. This may increase the intensity of emotional responses, such as discomfort and tension, potentially leading to poor sleep and even insomnia. 17 Some patients took carbamazepine or anticonvulsant medication before going to sleep, and these drugs can cause drowsiness that reduces the frequency of awakening. However, the awakening of a patient with pain is not accidental during sleep. About 60% of patients reported that they repeatedly awoke in sudden severe pain. Awakening was typically associated with touching the trigger-point involuntarily. 18 Therefore, we propose that carbamazepine and anticonvulsant medication do not provide a sleep protection mechanism during sleep, even if patients seldom wake up during sleep. Repeated and severe pain can affect sleep quality. In addition, long-term sleep disorders affect the synthesis of endogenous opiates and the functions of opioid receptors, reducing the pain threshold, and leading to a vicious circle. 19 The rate of cooccurrence of chronic pain and mental illness is reported to be as high as 65%, and depression is the most common type of cooccurring mental illness. 20 Zakrzewska et al reported that 35.7% of patients with trigeminal neuralgia had mild-to-severe depression, while more than 50% of patients had more serious anxiety disorders. 21 In the current study, 72 patients (62.6%) were positive for depression and anxiety separately, and sleep conditions were worse among these patients. Logistic regression analysis revealed that the degree of sleep disorders among depressed patients was 3.916 times greater than that of nondepressed patients. It is possible that different psychological disorders have negative effects on each other, reducing the quality of sleep in patients with trigeminal neuralgia. Moreover, these interactions may affect the prognosis of the disease.
Obsessive-compulsive disorder can be divided into obsession-type, compulsion-type, and mixed obsessive-compulsive type. About 50% of these patients have simple obsessions as the main clinical symptom that belongs to the category of anxiety mental illness. 22 In contrast, compulsion is a behavior performed to alleviate the subjective anxiety of patients. In essence, obsession is a prerequisite for compulsion. 23 Clinically, we found that the majority of patients feared washing their faces, brushing their teeth, eating, and drinking because of severe pain. This psychological fear was found to affect patients' lives and to take up a lot of their time, severely reducing their quality of life. However, we found that most patients did not have the corresponding compulsions in the process of communication. We speculate that this finding may be related to the fear caused by the paroxysmal pain involved in the disease. This may be slightly different from obsessive-compulsive disorder in the traditional sense, because it is not entirely caused by genetic, psychological, social, environmental, or other factors. Furthermore, the treatment of the patients in the current study did not require specific drug treatment for obsessions. 24 However, from a broader perspective, we propose that this phenomenon constitutes a type of obsession. Because the mental burden and life impact of obsessiveness is far greater than that of compulsion, 25 we primarily focused on patients' obsessions. Chi-square tests revealed that preoperative Y-BOCS obsessions scores were more serious among patients who were older, those with severe pain, and those in the anxiety-positive group. Logistic regression analysis revealed that the rate of obsessions in patients with pain in multiple branches was 4.279 times greater than that among patients with pain in a single branch. In addition, the rate of obsessions among anxiety-positive patients was 3.577 times greater than that of other patients with nonanxiety status. Stein et al reported that anxiety, depression, and even adverse drug reactions are major factors in aggravating obsessions disorder. 26 Severe, widespread, and desperate pain are also regarded as critical factors for obsession-related behavior. 8 In addition, long-term obsessions can lead to moderate or greater pain, which can cause a decline in social function, interpersonal relationships, and learning ability, resulting in depression, anxiety, and other mental discomfort, and the incidence is higher among older patients. 27 28 This is consistent with the results of our research.
In the current study, logistic regression analysis indicated that the incidence of sleep disorders and obsessions was higher among women than men. There were 57 female patients in our study, of which 47 had sleep disorders and obsessions. One potential explanation is that psychological adaptability, physical adaptability, and emotional venting of women were decreased compared with men, possibly due to the regulation of climacteric endocrine, differences in family, and work roles, or life pressures. 10 Several specific negative factors (such as production and obesity) may aggravate the development of mental illness, resulting in more serious negative reactions to trigeminal neuralgia, sleep disorders, and obsession symptoms among women. 29 30 It should be noted that the analysis of sleep and obsession disorders revealed that monthly household income was negatively correlated with both types of disorder. In addition, patients with lower income exhibited more severe sleep disorders and obsessions. It is possible that lower income patients are more worried about their financial situation in the course of treatment, which could increase their psychological burden and sense of pressure. 10 Moreover, low-income work is more likely to involve physical labor, and patients with low incomes may have lower social status and more complex family relationships, as well as a lack of support during the course of treatment. These factors could also potentially influence their emotions, and the effects are reported to be more prominent among low-income female patients. 31 32 33 This possibility was also supported by our clinical observation and communication data.
The etiology of trigeminal neuralgia is currently unclear, and neurovascular compression is one of the most widely accepted theories. 34 MVD is considered to be a safe and effective procedure, and is usually used as the first choice for treatment. 35 The early effectiveness rate of MVD for trigeminal neuralgia is 90 to 95%, and decreases to 75% after 1 year and 5 years of follow-up. 36 The current results revealed that the prognosis of patients with no recurrence after MVD was better than that of recurrent patients in terms of sleep disorders and obsessions, while the sleep quality of patients who did not undergo internal neurolysis for trigeminal nerve or artial sensory root sectioning was worse than that of patients who received surgical manipulation of the nerve. The follow-up results of 115 patients revealed that 18 patients (15.6%) had recurrence, including 11 (26.2%) cases of sleep disorders, and 5 (38.5%) cases of obsessions. We found that the recurrence of postoperative pain can lead to an increase of psychological fear, including a refusal of surgical treatment in some cases, as well as a distrust of doctors. This negative emotion also increased the psychological pressure to refuse treatment in future. Therefore, avoiding excessive traction during surgery and appropriate treatment of the veins are critical aspects of the surgical procedure. Thus, we believe that during MVD procedures, it is important to undertake exploration of relevant vessels and adequate decompression. In addition, avoiding excessive intraoperative traction, correct handling of the petrosal veins, and the specific details of MVD are important factors to consider. 37 Among the 25 patients receiving trigeminal nerve manipulation (including seven patients without obvious vascular compression), we implemented internal neurolysis for trigeminal nerve of 18 patients (15.6%), and partially section the sensory root of seven patients (6.1%). In addition, there were 11 patients suffering severe pain, 21 patients with positive depressive symptoms, as well as 19 anxiety-positive patients, preoperatively. Moreover, 22 patients had sleep disorders and 20 patients had obsessions, but improved significantly after MVD. In addition, the results revealed serious psychological symptoms in seven older patients (aged 65–84 years), who underwent partial sensory root sectioning during operation, and all the patients had sleep disorders and obsessions that did not show recurrence in follow-up. Although internal neurolysis and partially sensory root sectioning can cause facial anesthesia, the procedure also greatly reduces the recurrence rate. 38 Compared with severe pain, we believe that facial numbness is a desirable choice for patients who cannot endure a long period of pain. We believe that patients with older age and severe preoperative symptoms are suitable for undergoing internal neurolysis for trigeminal nerve or partially sensory root sectioning.
Because of the long-term facial numbness of some patients after internal neurolysis or partially section, we did not include this group of patients in the statistical analysis unless a patient also exhibited other symptoms of discomfort, such as nausea and vomiting, cerebrospinal fluid leakage, subcutaneous fluid, or intracranial infection. The results also revealed that there was no significant correlation between postoperative severe complications and prognosis. In addition, we found that sleep disorders and obsessions were both associated with lower postoperative 1-year scores compared with preoperative scores in the paired t -test. Patients' mental disorders typically improved after surgery.
Conclusion
Overall, for patients with trigeminal neuralgia, severe pain appears to be a critical component of sleep disorders and obsessions. Early and effective solutions for pain are an important goal for treating this physical and psychological condition, and MVD currently appears to be the best treatment option. MVD cannot only relieve the physical pain of patients, but can also improve psychological difficulties, greatly improving the overall therapeutic effect for trigeminal neuralgia. 5
Limitations
The current study involved several limitations that should be considered. First, since we only examined 115 patients with trigeminal neuralgia who presented to our department, our results may be prone to geographical selectivity bias. Second, the number of patients was relatively small. Thus, our sample may not be representative of the general population of trigeminal neuralgia patients. Currently, we only had 1-year follow-up data for all patients. We plan to continue data collection for this sample in an ongoing way. Thus, we plan to undertake a longer follow-up study with the patients in the current study, to explore the long-term psychological effects of MVD for postoperative patients with trigeminal neuralgia.
Footnotes
Conflict of Interest None declared.
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