A Comprehensive Profile of Clinical, Psychiatric ... - Wiley Online Library

Epilrpsiu, 40(9):1292-1298, 1999 Lippincott Williams & Wilkins, Inc., Philadelphia

0 International League Against Epilepsy

Clinical Research

A Comprehensive Profile of Clinical, Psychiatric, and Psychosocial Characteristics of Patients with Psychogenic Nonepileptic Seizures *Alan B. Ettinger, 3Orrin Devinsky, ?$Deborah M. Weisbrot, *$Ravindra K. Ramakrishna, and *$Amit Goyal Departments of *Neurology and fPsychiatry and the $Epilepsy Management Program, State University of New York at Stony Brook, Stony Brook: and $Department of Neurology and the Comprehensive Epilepsy Center, New York University School of Medicine, Hospital for Joint Diseases Orthopaedic Institute, New York, New York, U.S.A.

Summary: Purpose: To attain a comprehensive profile of clinical, psychiatric and psychosocial characteristics of patients with psychogenic nonepileptic seizures (NESs), and to assess the relation of these factors to NES outcome. Methods: We administered a telephone-based structured questionnaire to 56 patients with NESs (16 male and 40 female patients; mean age, 35 years) at a mean follow-up time of 18 months after making the diagnosis of NES. Results: Mean age of NES onset was 28 years with a mean duration of 8 years. Episodes resolved in 29 (51.8%) cases, decreased in 24 (42.9%), persisted unchanged in two (3.6%), and increased in frequency in one (1.8%). Thirty (53.6%) patients, including 13 (44.8%) of patients whose NESs resolved, were rehospitalized for NESs or for other symptoms. Twentynine ( 5 1.8%) had significant depressive symptoms, 22 (39.3%) had suicidal ideation, and 11 (19.6%) attempted suicide [including 6 (21%) of the patients whose NESs resolved]. Believ-

ing the NES diagnosis was associated with resolution or improvement of NES frequency (p c 0.029), whereas anger in response to receiving the diagnosis did not predict a poorer outcome. Patients’ perceptions of having good health (p < 0.02) and good occupational functioning (p < 0.04) were highly correlated with NES resolution. Only patients whose episodes resolved were employed at the time of follow-up. Conclusions: At a mean of 1.5 years, NES outcome was poor, with resolution in only half the group and with frequent rehospitalizations after NES diagnosis, even among patients whose NES resolved. Depressive symptoms, suicidal ideation, and suicide attempts were common. Believing the NES diagnosis and patient perceptions of having good health and good occupational functioning correlated well with NES resolution. Key Words: Nonepileptic seizures-Pseudoseizures-Outcome-Prognosis-Depression.

Psychogenic nonepileptic seizures (NESs, also known as pseudoseizures, or psychogenic or hysterical seizures) are clinical events that resemble epileptic attacks but are unassociated with physiologic central nervous system dysfunction (1,2). Although an abundant literature (3-8) focuses on the clinical distinctions between epileptic and NESs, relatively few studies have examined outcomes in patients with NESs (Table 1). Some of these studies were limited by small sample size (9), inclusion of patients with both epileptic and NESs (10-12), reliance on methods other than video-EEG to make the NES diagnosis (13,14), and marked variability in follow-up durations (1 2).

The current literature provides limited information about many clinical, psychiatric, and psychosocial characteristics of patients with pure NESs, such as episode precipitants, postictal symptoms, suicide rates, reactions to the receiving the NES diagnosis, and its relation with prognosis, frequency of hospitalizations for NESs after the NES diagnosis, and the correlation of social and occupational functioning with NES outcome. We therefore sought (a) to develop a comprehensive profile of these characteristics among patients with NESs who were rigorously diagnosed and who lacked concomitant active epilepsy, (b) to assess NES outcome, and (c) to identify factors that predict NES prognosis.

METHODS

AcceDted Januarv 19. 1999. Address correspondence and reprint requests to Dr. A. B. Ettinger at Epilepsy Management Program, Department of Neurology, Health Sciences Center T12-020. State Universitv of New York at Stonv Brook. Stony Brook, NY 11794-8121, U.S.A.’

Population We identified patients older than 12 years, diagnosed with NES between the dates of 1990 and 1996 at the New 1292

1293

PSYCHOGENIC NONEPILEPTIC SEIZURES TABLE 1. NES outcome studies No.

Duration of follow-up

Walczak, et al. 1995 (10)

72

15 mo

Lempert & Schmidt, 1990 (14)

50

24 mo

Kristensen & Alving, 1992 (30) Krumholz & Neidermeyer, 1983 ( I 1) Meierkord, et al. 1991 (12)

28 41

5.8 yr 5 Y‘

70

2 1 yr

Present study

56

Author, year

Outcome

Predictive features for good outcome

35% episode free 41% decreased S O % 34% episode free 22% reduced 45% episode free 29% episode free 15% reduced 40% episode free

52% episode free

18 mo

York University Hospital for Joint Diseases Comprehensive Epilepsy Center. Most patients were referred by community neurologists or self-referred for diagnostic or presurgical evaluation or for therapeutic intervention. Patients came from a broad range of socioeconomic and ethnic backgrounds (most patients were white). The majority came from the New York City metropolitan area. The NES diagnosis was based on a comprehensive neurologic evaluation and video-EEG monitoring that captured characteristic episodes during the recording. Episodes identified as NESs were not associated with postictal prolactin elevation, or electroencephalographic seizure correlate, and were clinically atypical for epileptic seizures (7,8). The diagnosis of NES was presented during the hospital stay (>90%) or at the first outpatient follow-up visit (I50

Persistent (n = 2)

Improved (n = 24)

Worsened (n = 1)

All cases = 56)

(n

Before Dx.

After Dx .

Before Dx.

After Dx.

Before Dx.

After Dx.

Before Dx.

After Dx.

Before Dx.

After Dx.

20,709 7,24.1% 2, 6.9% 0

0 0 0 0

l4,58.3% 6, 10.7% 2, 3.6% 2, 3.6%

22,91.6% l,4.2% I , 4.2% 0

],SO% 1,50% 0 0

1,50% 1,50% 0 0

],SO% 0 0 0

1,SO%

36,64.3% 14,25% 4,7.1% 2, 3.6%

53,94.6% 2, 3.6% 1, 1.8% 0

0 0 0

Epilepsia, Vol. 40, No. 9, 199Y

A. B. ETTINGER ET AL. TABLE 3. Hospitalizations and emergency room visits after the diagnosis of NES Reason for hospitalization (n, % within each outcome category) For NES

Other medical problems

Both NES and other

Total hospitalizations

ER visits

Outcome category Resolved cases Improved cases Persistent cases Worsened cases All cases

2 (6.9%) 4 (16.7%) 0 0 6 (10.7%)

10 (34.5%) 9 (37.5%) 1 (50.0%) 0 20 (35.7%)

1(3.4%) 1 (4.2%) 1 (50.0%) 1 (100%) 4 (7.1%)

13 (44.8%) 14 (58.3%) 2 ( 100%) 1 (100%) 30 (53.6%)

4 (7.1%) 9 (16.1%) 1 (50.0%) I(lOO%) 15 (26.8%)

(n, %)

time preceding NES diagnosis and the time of current follow-up for the following items:

follow-up period, as well as prior and current use of AEDs.

1. History and description of NES: These questions focused on age of NES onset, age at the time of NES diagnosis, symptoms experienced during and after episodes, precipitants of events, and use of AEDs. 2. Attitude toward diagnosis: This section examined patients’ feelings about receiving the NES diagnosis and whether they agreed or disagreed with the diagnosis. 3. Psychiatric variables: These questions dealt with symptoms of depression, any lifetime history of suicidal ideation and suicide attempts, and psychiatric interventions before and after the NES diagnosis. We also administered the Beck Depression Inventory (19), a 21-item self-report measure with scores > 16 suggestive of significant depressive symptoms. 4. General functioning: This section probed patients’ perceptions of changes in their general health, physical activity, occupational status, and relationships with family and friends.

Statistics We divided patients into two groups, one with subjects whose NESs resolved versus all others. The x2 statistic and the t test, where appropriate, were used to assess the relation of NES outcome to other variables.

RESULTS Seventy-six patients met study criteria. Eight patients could not be reached, two died (neither of suicide), and 10 declined to participate, leaving 56 patients [16 (28.6%) male; 40 (71.4%) female patients] who entered the study. (Demographic factors were similar between patients entered in the study and the 20 patients not included.) Neither gender, age of NESs, nor ethnicity predicted outcome. The mean duration of NES follow-up was 17.9 months (SD & 10.6 months). Mean age at the time of NES diagnosis was 33 years, with a range of 12-58 years (SD t- 12 years); mean age at follow-up was 34.73 years (SD f 11.94 years; range, 14-61 years). The mean age of NES onset was 27.8 years (range, 9-58 years; SD f 12.6). The mean NES duration was 7.79 years (SD 5 8.90; range, 1-38 years). None of these variables predicted NES outcome.

To investigate outcome, we examined the frequency of episodes at the time of follow-up. Patients reported whether they were episode free (“resolved”), had lessfrequent episodes (“improved”), had episode frequency unchanged (“persistent”), or had an increase in episode frequency (“worsened”). We inquired about hospitalizations for NESs or other reasons that occurred during the TABLE 4. Description

Outcome Episodes resolved in 29 (51.8%) cases, decreased in 24 (42.9%), persisted unchanged in two (3.6%), and increased in frequency in one case (1.8%). Specific epiof

NES clinical characteristics

During seizure

Resolved (n, % within each outcome category)

Improved (n. %)

Persistent (n, %)

Worsened (n, %I

All cases (n, %)

Physical movement Facial movement Tongue biting Conscious Incontinence Tired after seizure Remember seizure Related to stress

20 (83.3%) 12 (41.3%) 7 (24. I %) 9 (3 1.0%) 4 (13.8%) 24 (82.8%) 9 (3 1.O%) 18 (62.1%)

17 (70.8%) I 1 (45.8%) 8 (33.3%) 8 (33.3%) 7 (29.2%) 22 (91.7%) 10 (41.7%) 12 (50.0%)

0 0 0 0 0 2 ( 100%) I(50%) 1(50%)

1 (100%) 1 (100%)

38 (67.9%) 24 (42.9%) 15 (262%) 18 (32. I % ) 12 (21.4%) 49 (87.5%) 21 (37.5%) 32 (57.1%)

Epilepsici. Vo/. 40. No. Y, 1999

0 1 (1 00%) 1 (100%) 1 ( I 00%) 1 (100%) 1 (1 00%)

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PSYCHOGENIC NONEPILEPTIC SEIZURES

TABLE 5. Reactions to receiving the NES diagnosis Resolved (n, % within each outcome category)

Reactions

7 (24.1%) 12 (41.3%) 1 (3.4%) 26 (89.7%)

Anger Relief Other" Believe diagnosis (p < 0.029) I'

Persistent (n,

Worsened (n, %)

All cases (n, %)

5 (20.8%) 9 (37.5%)

1(50%) 0

0 0

13 (23.2%) 21 (37.5%)

17 (70.8%)

I(50%)

0

44 (78.6%)

Improved (n, 5%)

1(1.8%)

Data missing in three cases

sode frequencies before and after diagnosis are displayed in Table 2. Most patients had episode frequencies ranging from one to 50 episodes per month; two had >150 episodes per month. The mean duration of NES follow-up was 19.2 months (SD 10.8) in the group with resolved NES and 16.4 months (SD f 10.4) in the unresolved group (p = NS). Among the five patients between age 14 and 18 years, four became episode free, and one experienced a marked decrease in episode frequency. AEDs were not prescribed in 27 cases before diagnosis. Among the remaining 29 cases, AEDs were stopped in 17 (58.6%), continued in 11 (37.9%), and data were missing in one (3.4%) case. Table 3 displays the frequency and reasons for hospitalization after the NES diagnosis was revealed to patients. More than 50% of the entire sample was hospitalized. There was no statistically significant relation between postdiagnosis hospitalization and NES outcome. Most hospitalizations were for reasons other than NESs.

*

Description of NES Table 4 summarizes clinical characteristics of NESs as described by patients, including relation to stress and the postictal symptoms. Most patients (38; 67.9%) reported limb or truncal movements during their episodes. In 24 (42.9%) cases, facial movements occurred with or without movements of the limbs or trunk. Tongue-biting and incontinence were reported infrequently, whereas postictal fatigue was commonly reported. Among 15 (26.8%) cases who noted tongue-biting during an episode, eight were reported as involving the lateral tongue, three in the front, three in the front and lateral tongue, and data were missing in one case. Fewer than a third of patients noted preserved consciousness during episodes. Approximately

half of the patients considered their episodes to be stress related. None of these variables was predictive of outcome.

Attitude toward diagnosis Patients' reactions to receiving the NES diagnosis are represented in Table 5. Most patients with improved or abolished NESs stated that they believed the NES diagnosis (p < 0.029). However, a response of anger was independent of agreeing or disagreeing with the diagnosis and did not predict a poorer NES prognosis. Psychiatric variables Overall, 29 (51.8%) of the patients met criteria for significant depressive symptoms on the Beck Depression Inventory (14 in the abolished group, 12 in the improved group, two in the persistent unchanged group, and one patient with worsened NES). More than one third of patients overall (n = 22; 39.3%) had a history of suicidal ideation including 10 (34.5%) patients in the abolished group, nine (37.5%) patients in the improved group, two (100%) patients in the persistent unchanged group, and the one patient in the worsened group. A history of suicide attempts occurred in 11 (19.6%) overall, including six (20.7%) in patients whose NES resolved, four (16.7%) in patients with decreased NES frequency, and in the one patient with increased NES. The frequency and nature of psychiatric interventions before and after diagnosis are highlighted in Table 6. A minority of patients received psychiatric treatment before the NES diagnosis, whereas most sought psychiatric intervention after the diagnosis was made. Overall, 42 patients received a psychiatric intervention of some kind; 26 specifically saw a psychiatrist only, whereas five saw a psychiatrist as well as a counselor, social worker, or

TABLE 6. Psychiatric interventions

Counselor Psychologist Social worker Psychiatrist Other


Improved (n, %)

Persistent (n,

Worsened

1(3.4%) 4 (13.8%) 2 (6.9%) 13 (44.8%) 1 (3.4%)

1(4.2%) 5 (20.8%) 2 (8.3%) 15 (62.5%) 1 (4.2%)

0 1(50%) 0 2 (100%) 0

0

2 (3.6%)

0 0 I(lOO%) 0

10 (17.9%) 4 (7.1 %)

(n, %)

All cases (n, %)

31 (55.4%) 2 (3.6%)

Categories nut mutually exclusive.

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A. B. ETTINGER ET AL.

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TABLE 7. Patient perceptions of family, occupational, social, and physical functioning Family functioning (p < 0.057) Health functioning (p < 0.020) Occupational functioning (p < 0.037) Physical activity (p < 0.07) Social functioning (p < 0.098)

Abolished

Improved

Persistent

Worsened

All cases

14 (48.3%) 20 (69.0%) 14 (48.3%) 16 (55.2%) 13 (44.8%)

4 ( I 6.7%) 8 (33.3%) 3 (12.5%) 6 (25.0%) 4 (16.7%)

0 0 1(50%) 0 0

0 0 0 0 0

18 (32.1%) 28 (50.0%) 18 (32.1%) 22 (39.3%) 17 (30.4%)

psychologist. Eleven patients saw only a counselor, social worker, or psychologist. There was no statistically significant difference in outcome among patients who did or did not receive any intervention, or among different types of interventions.

General functioning Patients’ perceptions of changes in their general health and physical activity, occupational status, and relationships with family and friends are displayed in Table 7. Patients’ perceptions of good health (p < 0.02) and good occupational functioning (p < 0.04) were most highly correlated with resolution of NESs; there was a trend toward statistical significance between outcome and all other measured aspects of functioning as well. Patients’ employment and disability status are highlighted in Table 8. Most patients who were currently employed were in the group of patients whose NESs resolved (p = NS). Only patients whose episodes resolved were employed at the time of follow-up (n = 9). Patient marital relationships at the time of NES diagnosis are displayed in Table 9. Marital status did not predict NES outcome.

DISCUSSION Only half of our patients experienced resolution of NESs after an average of 18 months after diagnosis and recommended therapy. Further, >50% were rehospitalized, and 27% were evaluated in emergency rooms after the NES diagnosis was revealed, many for medical problems other than NESs. Although we could not determine whether their medical conditions were functional, we speculate that somatization (a common comorbid diagnosis among patients with conversion disorder) (20) may have been a contributing factor in many cases. Presenting the diagnosis and its nonorganic etiology may had led some patients to replace NESs with new confounding symptoms (i.e., symptom substitution). NES resolution in the face of new functional symptoms would still imply a suboptimal outcome. Together these findings suggest

that future studies should more accurately define the frequency and nature of other symptoms, the better to clarify true outcome in patients with NESs. Our rate of NES resolution was slightly higher than in most series (Table l), possibly because our study excluded patients with concomitant epilepsy whose epileptic seizures may have been mistaken for persistent NESs in some cases. Patients with persistent NESs may have more frequently refused to participate in the survey, biasing our results. The patient group whose NESs resolved had slightly longer mean durations of follow-up compared with other patients, suggesting that NES episodes would have resolved in some, given a longer observation period. However, the differences in follow-up durations were not statistically significant. Our approach to therapy was eclectic and included psychopharmacology for specific psychiatric disorders, psychotherapy, behavioral modification for patients with lower intelligence and poor insight, social work interventions, and family counseling. Whether this eclectic approach was more effective than others remains unknown. NES outcome in the five adolescent patients included NES resolution in four and improvement in one case. Although numbers were too small for statistical analysis, this trend is consistent with prior series (21,22) that demonstrated a better outcome in younger age groups. Similar to one study (1 2) and contrasting with others (10,l l), we found no relation between NES duration and outcome. However, if our population included more patients diagnosed within months of NES onset, a shorter NES duration may have correlated better with prognosis. The mean duration of NES before diagnosis was -8 years, with one patient experiencing NESs for 38 years. This suggests that the medical community should be better educated about recognizing the possibility of NESs and the value of referral for video-EEG monitoring to clarify diagnosis. Several factors were predictive of NES outcome. Patients whose NESs resolved were more likely to believe the diagnosis; however, an angry reaction did not pre-

TABLE 8. Employment status

Currently employed Employed at time of diagnosis Medical disability


Resolved

Improved

Persistent

Worsened

All cases

20 (69.0%) 1 I (37.9%) 9 (31.0%)

I 1 (45.8%) 1 1 (45.8%) 11 (45.8%)

1 (50%) I(50%) 0

0 1 ( I 00%) 1 (1 00%)

32 (57.1%) 24 (42.9%) 21 (37.5%)

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PSYCHOGENIC NONEPILEPTIC SEIZURES TABLE 9. Marital status at time of NES diagnosis Improved (n, %)

Persistent (n.

Worsened (n, %I

All cases

Marital status


Never married Married Divorced Widowed

15,51.7% 12,41.4% 2, 6.9% 0

9,37.5% 12,50% 2, 8.3% 1,4.2%

2, 100% 0 0 0

0 1, 100% 0 0

26, 46.4% 25,44.6% 4, 7.1% 1,1.8%

clude episode resolution, suggesting that patients may come to terms with the diagnosis over time. Patient perceptions of good functioning in many domains, especially general health and occupation, were significantly correlated with favorable NES outcome. The improved adjustment in such patients likely translates into more opportunity and more personal inclination to express stress and psychological conflicts in ways other than NESs. Interventions that promote better patient functioning and self-esteem could conceivably help patients overcome NESs. Whereas the objective documentation of tongue biting (particularly in the lateral portion of the tongue) is considered to be highly specific for epileptic seizures (23), 27% of our patients claimed to bite their tongues during these episodes, including the lateral aspects. Our study suggests that depending on subjective reports of tonguebiting will not reliably distinguish epileptic from NESs. Incontinence, a symptom that might be considered specific for epileptic seizures, occurred in 2 1% of our cases. Another survey of patients with NESs found even higher rates of reported incontinence (24). Nearly 50% of the patients reported a relation of stress to their episodes. Although it is intuitive to relate psychogenic episodes to a psychological precipitant, this relation is not specific to NESs. A separate survey focusing on seizure precipitants found a higher rate of stress-related episodes in patients with epilepsy than in patients with NESs (25). Stress is well recognized as a provocative or contributory factor for other medical (e.g., angina, asthma), neurologic (e.g., parkinsonian tremor), and psychiatric disorders. Symptoms of depression were common among our patients, consistent with a number of prior NES series ( I 1,14,26) and high rates of depression reported among patients with conversion disorders (20). However, depressive symptoms are unlikely to distinguish epileptic from nonepileptic disorders, because depression occurs in an estimated 20-60% of epilepsy cases (27,28). In a recent survey of 89 patients with epilepsy attending a tertiary center clinic (a setting likely to be the site of NES evaluations as well), 52% had significantly elevated depression scores on the Center for Epidemiologic StudiesDepression Scale (CES-D) (29). A very disturbing finding was the common history of suicidal ideation and suicide attempts, even among patients whose NESs resolved. These findings further sup-

h %)

port the need for intensive psychiatric intervention in this population. Our failure to demonstrate differences in outcome between patients who received or did not receive psychiatric interventions should be interpreted with caution. Although dissociative and conversion disorders that underlie the pathophysiology of NESs are often difficult to treat effectively, many other confounding factors may have influenced our results. Our study was not a randomized trial. Further, we have little insight into the specific nature and standardization of the interventions received or the degree of patient compliance with recommended therapies. A larger controlled series may be needed to demonstrate a positive effect. Our results were also limited by our reliance on symptom assessments by patients who may have amplified or minimized symptoms in some cases. Our study may also have been compromised by the usual limitations inherent in performing retrospective assessments. The diagnostic challenges of NESs have diminished in the age of video-EEG monitoring, whereas the therapeutic challenges have increased. Neurology and psychiatry can now reliably diagnose patients with NESs, but we remain uncertain why some patients enjoy symptom resolution after the diagnosis is presented and others continue to suffer from refractory NESs and other conversion and somatic symptoms. Understanding how the conversion symptoms developed, how patients react to the diagnosis, and how and when symptom substitution occurs may shed light on the underlying mechanism and long-term outcome.

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