BIOL i~YC},:IATRY 1991:30:205-209
Sleep Onset REM Periods in Schizophremc Patients Stephan F. Taylor, Rajiv Tandon, James E. Shipley, Alan S. Eiser, and JoAnn Goodson
Sleep EEG studies in depression have consis- REM (Zarcone et al 1987; Kempenaers et nl tently shown shortened rapid-eye-movement 1988). We ~dertook the f o H o ~ g retrospec(REM) iatem;y in m ~ y patients (Kupfer et al five analysis of our schizophrenia-sleep data 1986), with a smaller subset expe~encing sleep- base, comparing patients who experienced onset REM (SOREM), defined as the onset of SOREM periods with those who ~ not to see REM within 10-20 rain of the onset of sleep. whether the groups showed differences in In depression, SOREMs have been associated clinical presentation, sleep variables, or progwith greater illness severity (Reynolds et al nosis. 1985; Coble et al 1981), psychotic symptoms (Coble et al 1981; Kupfer et al 1986; Thase M e t h o d s et al 1986), and older age (Schultz et al 1979; Ansseau et al 1984; Reynolds et al 1985; The sample consisted of 36 schizophrenic inKupfer et al 1986; Kumar et al 1987). Re- patients (mean age = 28.6 _+ 7.7, range 19search to date cannot yet determine whether 47) diagnosed by SADS/RIX~ and D S M - ~ criteria who gave informed consent to particiSOR~t'~ts represent an extension of the same process or pr~-.esses that cause shorteninE of pate in the study. After a minimum of 2 weeks REM latency or result from a different pro- free of medication, they underwent two concess. Kupfer and Ehlers (1989) have sug- secutive nights of sleep EEG studies in their gested that SOREMs may indicate shortening own hospital beds, with the first night for adsleep dis. of REM latency because of increased REM aptation and to rule out any ~ turbance, such as sleep apnea. Data from the "pressure," as opposed to deficient slow-wave sleep, wl-dch coulo also shorten REM latency. second .njg.ht ovJy we~ u~d m ~ e ~,-_--a!ysis. Patients were clinically screened to exclude Examination of this process in schizophrenic those with signs of narcolepsy, and staff prepatients may be useful, becau:e some schizovented patients from napping on the days when phrenic patients, like depressed patients, exsleep studies were performed. Placement of hibit shortened REM latencies, including SOelectrodes and scoring were in accord with the methods described by Rechtschaffen and Kales (1968). Sleep onset was defined as the first From the SchizophreniaProgram (SFT, RT, JG) and Sleep Diagminute of stage 2 sleep followed by at least nostic and ResealchProgram (JES, ASE), Universityof Michigan Departmentof Psychiatry, 1500 East MedicalCenter Drive, Ann 10 rain of stage 2 sleep not interrupted by more Arbor, M148109-0120. than 2 rain awake or in stage 1. REM latency Address ~'l~rintrequests to Stephan F. Taylor, M.D., Universityof Michigan, Departmentof psychiatry, 1500 East Medical Center was defined as the time between sleep onset Drive, Ann Arbor, MI 48109-0120. and the occurrence of the first REM period of Received September 13, 1990; revised December9, 1990. Presentedat the New Research Poster Session of the 143nl Annual at least 3 rain duration, minus intervening time Meetingof the AmericanpsychiatricAssociation,New York, May awake (RLMA). 12-17, 1990. © 1991 Society of Biological Psychiatry
0006-3223/91/$03.50
Brief Repmts
BIOL PSYCHIATRY 1991;30:205-209
Once during the medication-free period and once after 4 weeks of treatment with 8-30 mg haloperidol equivalents, patients were assessed by the Brief Psychiatric Rating Scale (BPRS), the Scale for the Assessment of Negative Symptoms (SANS), and the Hamilton Rating Scale for Depression (HRSD, 17 item). One-year follow-up was done on 27 patients and scored according to the Strauss-Carpenter Outcome Scale (Strauss and Carpenter 1972).
Results Of the 36 patients, 6 (16.7%) experienced REM latency less than l0 min and I experienced a REM latency between l0 and 20 min. As seen in Figure l, u~e distribution of REM iatencies suggests a bim~'~lal distribution. Using the strict definition of SO.~F.M ~ REM onset < 10 rain, we have compared these 6 patients with SOREM with the remaining ~0 patients with R L ~ ~> 10 rain. The SOREM and the n o n - S O ~ ~ p did not differ significantly in age at the time of the study or at the onset of illness, duration of iflness, number of hospitalizations, education, sex distribution, or subtype distribution (Table 1). Only 1 patient in the SOREM group had never been on medication, and of those who had been, 2 of 5 had been medication-free for more tha~ 4 weeks, compared with 9 of 15 in the nonSOV~EM group.
Analysis of sleep v~iables was by MannWhitney U test. With regard to measures of steep (Table 2), the SOREM group differed from ~ - $ O R E M group only in having a shorter first ~ period and less first period REM activity. The two groups exhibited no significant differetges in other measures of REM sleep, ~ u r e s of sleep continuity, or sleep architecOwe.
Two-way analysis of variance (ANOVA) of rating scales (Table !), with pretreatment and posttreatment scales as repeated measures, revealed a strong group effect for SANS scores (df = 1,34, p < 0.005). Post hoc t-test with degrees of freedom corrected for the disparity in sample sizes (Glantz 1987) showed greater negative symptoms pretre~tment and posttreatmerit in the SOREM ,oroup. We found a group effect for BPRS total scores (df = !,34, p = 0.05), but these scores did not differ by post hoe t-test. BPRS positive subscales (conceptual disorganization, suspiciousness, hallucinatory behavior, and unusual thought content) and HR~D scotes did not differ between the groups. ANOVA also revealed a very strong treatment effect for all scales (df = 1,34, p < 0.0001), and no treatmentby group interaction, indicating that both groups improved equally with treatment. On the Suauss-Ca~enter Outcome Sca~e, the SOREM group had significantly tmot~ global functioning at 1 year by Student's t-test.
'0
Figure 1. Frequency distributions of REM latencies in schizophrenic patients (n -- 36
.
o.
0
.mll. 20
40
Jli 60
pallets).
mB | 80
100
120
~40
REM latency minus awake minutes
160
Brief Reports
i~.~L ~ Y C H I A ~ Y
207
T ~ l e 1. Characteristics o f S O R E M and N o n - S O R E M S c h i z o p h ~ n i c s
Variable Age (yr)
Sex Age atonset Fxluc~ion (yr) Duration of illness (too) Number of hospitalizations Humber neuroleptic naive (%) DSM-mR subqrpes Paranoid Undifferentiated Disorganized
SOREM In = 6) Mean ± S D
Non-SOREM In = 30) Mean ± S D
32.2 ± 9.7~
27.9 ± 7.34
l~or
3M, 3F
21 M, 9F
1°24 0,9
27.5 ± I!.1 12.3 ± 1.4
23,0 ± 7°| 13.1 ± 2.4
0,76
NS NS NS NS
56.8 ± 75.5
48.2 ± 60.3
0.39
NS
3.3 ± 4.1
1.9-*- 3.0
1.03
NS
15 i.~)
2.26
NS
2.17 1.39
= 0.05 NS NS NS
I 116.7)
1,29
Patients in) 2 4 0
13 15 2
v~riables BPRS total P~xeatment P o s i t BPRS positive symptoms Prelxeatment Posttreatment
4.12 53.8 _ 8.9 39.7 ± 5.3
46.2 ± 7.6 35.4 ± 7.1
16.5 ± 3.1 11.2 ± 2.6
14.3 _ 2.7 9.8 ± 3.0
16.0 ± 2.0 12.5 ± 3.6
! i. 1 ± 4.2 7.6 ± 2.7
14.7 ± 2.2 8.5 ± 2.7
13.8 ± 4.7 8.7 ± 4.2
2.51
SANS Prel~ment Posttreatment HRSD Pretreatment Posttreatment Outcome: Global functionb
12.23 2.76 3.84
0.005 0.05 0.01 NS
3.39
0.0|
0.065
7.2 ± 3.1 c
12.0 ± 3.1
"For t-I~sts, df coffected zcconting to Glantz (Z987). the non-SOREM group, n = 21. 'Higher score nmms better outcome.
Discussion Our percentage of patients with SOREM (16.7%) compares to Zarcone et al (1987), who fo~md 3 of 12 schizophrenic patients (25%) to have a RLMA of less than 15 min. Kempenaers et al (1988) report REM iatencies of less than 20 rain in 3 of 26 patient-nights. SOREMs can occur in normals when the sleep-wake cycle is altered (Carskadon and Dement 1975) and have been described in amphetamine withdrawal, but nei-
ther of these factors a p ~ to be operative with our patients. One has to consider the possible effects of neuroleptic withdrawal with only a 2-week washout period, although half of our SOREM patients had either never been on psychotropics or had been withdrawn for more than 4 weeks. SOREM periods in our schizophrenic patients have relatively short durations when compared with SOREMs in depressives, which tend to be long (Ansseau et al I984), e~cept when
Bnef Repmts
BIOL PSYCHIATRY 1991;30:205-209
Table 2. Sleep Parameters ,,
,m,
REM latency minus awake, min
SOREM (n = 6 )
Mean -,- SD 3.7 4- 3.3 Sleep continuity Sleep latency (rain) 70.3 ± 60.5 Total time asleep (rain) 296.3 ± 85.9 Arousals 5.2 ± 3.2
nisms involved in the control of REM sleep Non-SORID4 onset and duration. (n =
30)
Mean 4. SD 64.6 4- 31.7 75.7 • 65.7 307.4 4- 80.2 4.4 "," 4.0
Early mom~ awakening (rain) Sleep efficiency (%) Sleep maintenance (%) Sleep architecture Stage 1% Stage 2 % Delta % REM % REM sleep REM periods Total REM time (rain) Total R E M activity Total REM density First REM period Time (rain) Activity Density
13.5 ± 18.3 72.5 - 20.4 90.3 _ 12.7
5.8 4- !1.8 74.6 4- 17.4 93.9 4-¢.8.1
13.2 52.1 8.6 26.1
-,- 6.7 4- 6.5 "" 5.9 "4" 5.5
13.8 52.1 10.3 23.8
3.8 76.2 88.3 I. 13
± 1.3 4- 22.1 4- 43.7 -4" .25
3.1 -*- 1.0 72.4 4- 28.8 86.3 -.- 52.1 !. 16 - .47
7.2 _-. 3.4" 8.3 4- 4.6 b !.2 -,- .55
20.4 -*- 12.4 22.9 4- 17.9 !.1 4- .61
-" 6.2 -*" 10r.8 4- !!.6 _ 7.7
< 0.005 by Mann-Whitney U test. < 0.01 by Mann-Whitney U test.
psychosis accompanies the depression (Thase et al 1986; Ganguli et al 1987). Schizophrenic patients with SOREM, compar~ ".,,'i~ those without SOREM, had a shorter first REM period, more negative syn~oms both before and ~ _ , j ~ ~ t _ ~_mi poorer global functioning at 1 year. SOREMs may simply indicate greater overall severity (higher pretreatment BPRS and SANS scores and poor outcome), and that would be consistent with the demonstrated association between shortened REM latency (Tandon et al 1989) and the poor outcome associated with negative symptoms in schizophrenia (Andreasen 1982). After neuroleptic Ucaunent, the major differences occur in ratings of negative symptoms, suggesting that additional reseerch examine the links between persistent negative symptomatology and neurotransmitter mecha-
References Aadtemen N 0982): Negative s ~ in schizoDefmitioa and reliability. Arch Gem P ~ -
¢~
39:7~--788, M, Kupfer DI, Reynolds CF, McEadmm
AB (1984): ~ letency in major ~ : ~ chmcm~ ~ wi~ steep emet REM periods. B/o/PsycMmry 19:1651-1666.
MA, Demeat w c (19"/5): Sleep studies on a 90-n~ute day. E/ectromcepha/o~ C/in Neurophysiol 39:!45. C ~ l e PA, Kupfer DL Shaw DH (1981): Distribution
of REM latency in depression. B ~ P s y c ~ 16:453--4~. R, R:ynolde CF, Kupfer DJ (1987): Elec-
eoen~d~p:pbic sleep in young, aevm'-medicated ~ e n k s . Arch ~ Psychiatry44:3644. Cdantz SA (!987): Primer of Biosmasgcs, 2ad ed. New York: McCnaw-Hill, pp 77-78. K ~ C, Kerkhofs M, Linkowski P, Mendlewicz (1988): Sleep EEG variables in young
schizophrenic and delm~ive patients. Bio/Psych/arty 24:833--838. Kumar A0 Shipley JE, Eiser AS, et al (1987): Clinkal correlates of sleep onset REM periods in degession. Biol Psychiatry 22:1477-1481. Kupfer DJ, Ehlers CL (1989): Two roads to rapid eye movement latency. Arch Gen P s y c ~ y 46:945-948. Kupfer DJ, Reynolds CF, Gmchocinski VJ, Ulrich RF, McEachnm A (1986): Aspects of short REM latency in affective states: A revisit. Psychiatry Res 17:49-59. Rechtschaffen A, Kales A (1968): A Manua/of Stan-
dardized Terminology, Techm'ques and Scoring Systemfor Sleep States of Human Subjects. Washington, DC: Public Health Service; US Government P r i n ~ g Office. Reynolds CF, Kupfer DJ, Taska LS, et al (1985): EEG sleep in elderly depressed, demented and healthy subjects. Biol Psychi~ry 20:431442. Schulz H, Lurid R, Cording C, Dirlich G (1979): Bimodal distribution of REM sleep latencies in depression. Biol Psychiatry. 14:595--600. Strauss JS, Carpenter WT (1972): l ~ e prediction of
Brief Reimm
oetcome in schizophrenia: 1. Chara~.eristics of oetconm. Arch Gen Psychiatry 27:739-746. Tandon R, Shipley JE, Eiser AS, Ggeden JF (1989): Association between abnormal REM sleep and negative symptoms in schizopluenin. Psych/any Res 27:359-361.
e~L rSV~Y
Thase ME, Kupfer DJ, Ul~'h RF (1986):
encep~ogn¢~ sleep in psychotic,~msiou. Arch Gen P s y c ~ w y 43:886-893. Zaa:o~ VP, ~ KL, ~ PA (1987): Abnormal ~ eye movement ~ i e s in s c ~ ~ . ArchGen P ~ c ~ 44:45-48.
Sleep Onset REM Periods in Schizophremc Patients Stephan F. Taylor, Rajiv Tandon, James E. Shipley, Alan S. Eiser, and JoAnn Goodson
Sleep EEG studies in depression have consis- REM (Zarcone et al 1987; Kempenaers et nl tently shown shortened rapid-eye-movement 1988). We ~dertook the f o H o ~ g retrospec(REM) iatem;y in m ~ y patients (Kupfer et al five analysis of our schizophrenia-sleep data 1986), with a smaller subset expe~encing sleep- base, comparing patients who experienced onset REM (SOREM), defined as the onset of SOREM periods with those who ~ not to see REM within 10-20 rain of the onset of sleep. whether the groups showed differences in In depression, SOREMs have been associated clinical presentation, sleep variables, or progwith greater illness severity (Reynolds et al nosis. 1985; Coble et al 1981), psychotic symptoms (Coble et al 1981; Kupfer et al 1986; Thase M e t h o d s et al 1986), and older age (Schultz et al 1979; Ansseau et al 1984; Reynolds et al 1985; The sample consisted of 36 schizophrenic inKupfer et al 1986; Kumar et al 1987). Re- patients (mean age = 28.6 _+ 7.7, range 19search to date cannot yet determine whether 47) diagnosed by SADS/RIX~ and D S M - ~ criteria who gave informed consent to particiSOR~t'~ts represent an extension of the same process or pr~-.esses that cause shorteninE of pate in the study. After a minimum of 2 weeks REM latency or result from a different pro- free of medication, they underwent two concess. Kupfer and Ehlers (1989) have sug- secutive nights of sleep EEG studies in their gested that SOREMs may indicate shortening own hospital beds, with the first night for adsleep dis. of REM latency because of increased REM aptation and to rule out any ~ turbance, such as sleep apnea. Data from the "pressure," as opposed to deficient slow-wave sleep, wl-dch coulo also shorten REM latency. second .njg.ht ovJy we~ u~d m ~ e ~,-_--a!ysis. Patients were clinically screened to exclude Examination of this process in schizophrenic those with signs of narcolepsy, and staff prepatients may be useful, becau:e some schizovented patients from napping on the days when phrenic patients, like depressed patients, exsleep studies were performed. Placement of hibit shortened REM latencies, including SOelectrodes and scoring were in accord with the methods described by Rechtschaffen and Kales (1968). Sleep onset was defined as the first From the SchizophreniaProgram (SFT, RT, JG) and Sleep Diagminute of stage 2 sleep followed by at least nostic and ResealchProgram (JES, ASE), Universityof Michigan Departmentof Psychiatry, 1500 East MedicalCenter Drive, Ann 10 rain of stage 2 sleep not interrupted by more Arbor, M148109-0120. than 2 rain awake or in stage 1. REM latency Address ~'l~rintrequests to Stephan F. Taylor, M.D., Universityof Michigan, Departmentof psychiatry, 1500 East Medical Center was defined as the time between sleep onset Drive, Ann Arbor, MI 48109-0120. and the occurrence of the first REM period of Received September 13, 1990; revised December9, 1990. Presentedat the New Research Poster Session of the 143nl Annual at least 3 rain duration, minus intervening time Meetingof the AmericanpsychiatricAssociation,New York, May awake (RLMA). 12-17, 1990. © 1991 Society of Biological Psychiatry
0006-3223/91/$03.50
Brief Repmts
BIOL PSYCHIATRY 1991;30:205-209
Once during the medication-free period and once after 4 weeks of treatment with 8-30 mg haloperidol equivalents, patients were assessed by the Brief Psychiatric Rating Scale (BPRS), the Scale for the Assessment of Negative Symptoms (SANS), and the Hamilton Rating Scale for Depression (HRSD, 17 item). One-year follow-up was done on 27 patients and scored according to the Strauss-Carpenter Outcome Scale (Strauss and Carpenter 1972).
Results Of the 36 patients, 6 (16.7%) experienced REM latency less than l0 min and I experienced a REM latency between l0 and 20 min. As seen in Figure l, u~e distribution of REM iatencies suggests a bim~'~lal distribution. Using the strict definition of SO.~F.M ~ REM onset < 10 rain, we have compared these 6 patients with SOREM with the remaining ~0 patients with R L ~ ~> 10 rain. The SOREM and the n o n - S O ~ ~ p did not differ significantly in age at the time of the study or at the onset of illness, duration of iflness, number of hospitalizations, education, sex distribution, or subtype distribution (Table 1). Only 1 patient in the SOREM group had never been on medication, and of those who had been, 2 of 5 had been medication-free for more tha~ 4 weeks, compared with 9 of 15 in the nonSOV~EM group.
Analysis of sleep v~iables was by MannWhitney U test. With regard to measures of steep (Table 2), the SOREM group differed from ~ - $ O R E M group only in having a shorter first ~ period and less first period REM activity. The two groups exhibited no significant differetges in other measures of REM sleep, ~ u r e s of sleep continuity, or sleep architecOwe.
Two-way analysis of variance (ANOVA) of rating scales (Table !), with pretreatment and posttreatment scales as repeated measures, revealed a strong group effect for SANS scores (df = 1,34, p < 0.005). Post hoc t-test with degrees of freedom corrected for the disparity in sample sizes (Glantz 1987) showed greater negative symptoms pretre~tment and posttreatmerit in the SOREM ,oroup. We found a group effect for BPRS total scores (df = !,34, p = 0.05), but these scores did not differ by post hoe t-test. BPRS positive subscales (conceptual disorganization, suspiciousness, hallucinatory behavior, and unusual thought content) and HR~D scotes did not differ between the groups. ANOVA also revealed a very strong treatment effect for all scales (df = 1,34, p < 0.0001), and no treatmentby group interaction, indicating that both groups improved equally with treatment. On the Suauss-Ca~enter Outcome Sca~e, the SOREM group had significantly tmot~ global functioning at 1 year by Student's t-test.
'0
Figure 1. Frequency distributions of REM latencies in schizophrenic patients (n -- 36
.
o.
0
.mll. 20
40
Jli 60
pallets).
mB | 80
100
120
~40
REM latency minus awake minutes
160
Brief Reports
i~.~L ~ Y C H I A ~ Y
207
T ~ l e 1. Characteristics o f S O R E M and N o n - S O R E M S c h i z o p h ~ n i c s
Variable Age (yr)
Sex Age atonset Fxluc~ion (yr) Duration of illness (too) Number of hospitalizations Humber neuroleptic naive (%) DSM-mR subqrpes Paranoid Undifferentiated Disorganized
SOREM In = 6) Mean ± S D
Non-SOREM In = 30) Mean ± S D
32.2 ± 9.7~
27.9 ± 7.34
l~or
3M, 3F
21 M, 9F
1°24 0,9
27.5 ± I!.1 12.3 ± 1.4
23,0 ± 7°| 13.1 ± 2.4
0,76
NS NS NS NS
56.8 ± 75.5
48.2 ± 60.3
0.39
NS
3.3 ± 4.1
1.9-*- 3.0
1.03
NS
15 i.~)
2.26
NS
2.17 1.39
= 0.05 NS NS NS
I 116.7)
1,29
Patients in) 2 4 0
13 15 2
v~riables BPRS total P~xeatment P o s i t BPRS positive symptoms Prelxeatment Posttreatment
4.12 53.8 _ 8.9 39.7 ± 5.3
46.2 ± 7.6 35.4 ± 7.1
16.5 ± 3.1 11.2 ± 2.6
14.3 _ 2.7 9.8 ± 3.0
16.0 ± 2.0 12.5 ± 3.6
! i. 1 ± 4.2 7.6 ± 2.7
14.7 ± 2.2 8.5 ± 2.7
13.8 ± 4.7 8.7 ± 4.2
2.51
SANS Prel~ment Posttreatment HRSD Pretreatment Posttreatment Outcome: Global functionb
12.23 2.76 3.84
0.005 0.05 0.01 NS
3.39
0.0|
0.065
7.2 ± 3.1 c
12.0 ± 3.1
"For t-I~sts, df coffected zcconting to Glantz (Z987). the non-SOREM group, n = 21. 'Higher score nmms better outcome.
Discussion Our percentage of patients with SOREM (16.7%) compares to Zarcone et al (1987), who fo~md 3 of 12 schizophrenic patients (25%) to have a RLMA of less than 15 min. Kempenaers et al (1988) report REM iatencies of less than 20 rain in 3 of 26 patient-nights. SOREMs can occur in normals when the sleep-wake cycle is altered (Carskadon and Dement 1975) and have been described in amphetamine withdrawal, but nei-
ther of these factors a p ~ to be operative with our patients. One has to consider the possible effects of neuroleptic withdrawal with only a 2-week washout period, although half of our SOREM patients had either never been on psychotropics or had been withdrawn for more than 4 weeks. SOREM periods in our schizophrenic patients have relatively short durations when compared with SOREMs in depressives, which tend to be long (Ansseau et al I984), e~cept when
Bnef Repmts
BIOL PSYCHIATRY 1991;30:205-209
Table 2. Sleep Parameters ,,
,m,
REM latency minus awake, min
SOREM (n = 6 )
Mean -,- SD 3.7 4- 3.3 Sleep continuity Sleep latency (rain) 70.3 ± 60.5 Total time asleep (rain) 296.3 ± 85.9 Arousals 5.2 ± 3.2
nisms involved in the control of REM sleep Non-SORID4 onset and duration. (n =
30)
Mean 4. SD 64.6 4- 31.7 75.7 • 65.7 307.4 4- 80.2 4.4 "," 4.0
Early mom~ awakening (rain) Sleep efficiency (%) Sleep maintenance (%) Sleep architecture Stage 1% Stage 2 % Delta % REM % REM sleep REM periods Total REM time (rain) Total R E M activity Total REM density First REM period Time (rain) Activity Density
13.5 ± 18.3 72.5 - 20.4 90.3 _ 12.7
5.8 4- !1.8 74.6 4- 17.4 93.9 4-¢.8.1
13.2 52.1 8.6 26.1
-,- 6.7 4- 6.5 "" 5.9 "4" 5.5
13.8 52.1 10.3 23.8
3.8 76.2 88.3 I. 13
± 1.3 4- 22.1 4- 43.7 -4" .25
3.1 -*- 1.0 72.4 4- 28.8 86.3 -.- 52.1 !. 16 - .47
7.2 _-. 3.4" 8.3 4- 4.6 b !.2 -,- .55
20.4 -*- 12.4 22.9 4- 17.9 !.1 4- .61
-" 6.2 -*" 10r.8 4- !!.6 _ 7.7
< 0.005 by Mann-Whitney U test. < 0.01 by Mann-Whitney U test.
psychosis accompanies the depression (Thase et al 1986; Ganguli et al 1987). Schizophrenic patients with SOREM, compar~ ".,,'i~ those without SOREM, had a shorter first REM period, more negative syn~oms both before and ~ _ , j ~ ~ t _ ~_mi poorer global functioning at 1 year. SOREMs may simply indicate greater overall severity (higher pretreatment BPRS and SANS scores and poor outcome), and that would be consistent with the demonstrated association between shortened REM latency (Tandon et al 1989) and the poor outcome associated with negative symptoms in schizophrenia (Andreasen 1982). After neuroleptic Ucaunent, the major differences occur in ratings of negative symptoms, suggesting that additional reseerch examine the links between persistent negative symptomatology and neurotransmitter mecha-
References Aadtemen N 0982): Negative s ~ in schizoDefmitioa and reliability. Arch Gem P ~ -
¢~
39:7~--788, M, Kupfer DI, Reynolds CF, McEadmm
AB (1984): ~ letency in major ~ : ~ chmcm~ ~ wi~ steep emet REM periods. B/o/PsycMmry 19:1651-1666.
MA, Demeat w c (19"/5): Sleep studies on a 90-n~ute day. E/ectromcepha/o~ C/in Neurophysiol 39:!45. C ~ l e PA, Kupfer DL Shaw DH (1981): Distribution
of REM latency in depression. B ~ P s y c ~ 16:453--4~. R, R:ynolde CF, Kupfer DJ (1987): Elec-
eoen~d~p:pbic sleep in young, aevm'-medicated ~ e n k s . Arch ~ Psychiatry44:3644. Cdantz SA (!987): Primer of Biosmasgcs, 2ad ed. New York: McCnaw-Hill, pp 77-78. K ~ C, Kerkhofs M, Linkowski P, Mendlewicz (1988): Sleep EEG variables in young
schizophrenic and delm~ive patients. Bio/Psych/arty 24:833--838. Kumar A0 Shipley JE, Eiser AS, et al (1987): Clinkal correlates of sleep onset REM periods in degession. Biol Psychiatry 22:1477-1481. Kupfer DJ, Ehlers CL (1989): Two roads to rapid eye movement latency. Arch Gen P s y c ~ y 46:945-948. Kupfer DJ, Reynolds CF, Gmchocinski VJ, Ulrich RF, McEachnm A (1986): Aspects of short REM latency in affective states: A revisit. Psychiatry Res 17:49-59. Rechtschaffen A, Kales A (1968): A Manua/of Stan-
dardized Terminology, Techm'ques and Scoring Systemfor Sleep States of Human Subjects. Washington, DC: Public Health Service; US Government P r i n ~ g Office. Reynolds CF, Kupfer DJ, Taska LS, et al (1985): EEG sleep in elderly depressed, demented and healthy subjects. Biol Psychi~ry 20:431442. Schulz H, Lurid R, Cording C, Dirlich G (1979): Bimodal distribution of REM sleep latencies in depression. Biol Psychiatry. 14:595--600. Strauss JS, Carpenter WT (1972): l ~ e prediction of
Brief Reimm
oetcome in schizophrenia: 1. Chara~.eristics of oetconm. Arch Gen Psychiatry 27:739-746. Tandon R, Shipley JE, Eiser AS, Ggeden JF (1989): Association between abnormal REM sleep and negative symptoms in schizopluenin. Psych/any Res 27:359-361.
e~L rSV~Y
Thase ME, Kupfer DJ, Ul~'h RF (1986):
encep~ogn¢~ sleep in psychotic,~msiou. Arch Gen P s y c ~ w y 43:886-893. Zaa:o~ VP, ~ KL, ~ PA (1987): Abnormal ~ eye movement ~ i e s in s c ~ ~ . ArchGen P ~ c ~ 44:45-48.
