- Email: [email protected]
Laboratory findings in emergently medicated psychiatry patients
General Hospital Psychiatry 26 (2004) 411 – 414
Laboratory findings in emergently medicated psychiatry patientsB Tracy L. Schillerstrom, M.D.*, Jason E. Schillerstrom, M.D., Sally E. Taylor, M.D. Department of Psychiatry, The University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA Received 18 December 2003; accepted 29 June 2004
Abstract Objective: To determine routine laboratory differences between patients with severe psychomotor agitation who require emergency intramuscular (IM-medicated patients) medication and those who do not (non–IM-medicated patients). Method: A retrospective chart review of patients 18 years or older who went to a psychiatry emergency service over a 30-day period was performed. Demographic and laboratory variables were compared between IM- and non–IM-medicated patients. Results: Emergently medicated patients (n = 35) were older than non–IM-medicated patients (n = 179) (42.6 vs 34.3 years, P b.001). Patients receiving emergency IM medications had higher leukocyte (WBC) count ( P = .04), blood urea nitrogen ( P = .001), creatinine ( P = .01), glucose ( P = .009), aspartate aminotransferase ( P b.001), alanine aminotransferase ( P = .01), and electrocardiogram QTc interval ( P = .03). They were also more likely to have abnormal levels of potassium ( P b.05), glucose ( P b.05), aspartate aminotransferase ( P b.001), and alanine aminotransferase ( P b.05). Conclusions: Emergently medicated patients in this psychiatry emergency service were more likely to be older and more likely to have abnormal laboratories vs other adult patients. D 2004 Elsevier Inc. All rights reserved.
1. Introduction Patients with severe psychomotor agitation evaluated by a psychiatry emergency service (PES) often require emergency intramuscular (IM) medications to manage violent behaviors. For safety reasons, these patients are sometimes medicated before the completion of a medical history and laboratory studies. The medications used can have serious medical side effects. For example, haloperidol has been associated with elevated glucose levels and increased corrected electrocardiogram (ECG) QTc interval [1,2]. Atypical antipsychotics, now being marketed for emergency use, can also affect glucose metabolism and cardiac conduction [1,3–5]. It is our impression that a widely held assumption is that there are no medical differences between agitated and nonagitated psychiatry patients. Baseline medical differences between agitated and nonagitated patients in actual B
No funding was used or solicited for this work. * Corresponding author. Tel.: +1 210 567 5430; fax: +1 210 567 6941. E-mail address: [email protected] (T.L. Schillerstrom). 0163-8343/$ – see front matter D 2004 Elsevier Inc. All rights reserved. doi:10.1016/j.genhosppsych.2004.06.004
clinical practice have not been previously reported. Severely agitated patients may be more medically vulnerable than nonagitated patients. This pilot study aims to identify laboratory differences between severely agitated psychiatry patients who require emergency IM medication (IMmedicated patients) and those who do not (non–IMmedicated patients).
2. Methods 2.1. Subjects and setting Institutional Review Board approval for this study was obtained from The University of Texas Health Science Center at San Antonio before data collection. A retrospective chart review of all patients 18 years or older who went to a PES in a large public hospital was performed. Consecutive charts of patients evaluated between April 1, 2002, and April 30, 2002, were reviewed. The PES is a 5-room/5-bed center separate from the medical emergency center. It is staffed 24 hours per day by rotating psychiatry residents. On-site faculty supervision is
412
T.L. Schillerstrom et al. / General Hospital Psychiatry 26 (2004) 411 – 414
present 14 hours per day. The nursing and support staff are specifically trained in the treatment and management of persons with severe mental illness.
Table 2 Median laboratory values of IM- vs non–IM-medicated patients Laboratory
IM-medicated patients
Non–IMmedicated patients
Z
P
WBC (cells per AL) Hemoglobin (g/dL) Hematocrit (cells per AL) Platelets (cells per AL) Sodium (mmol/L) Potassium (mmol/L) Chloride (mmol/L) Bicarbonate (mmol/L) BUN (mg/dL) Creatinine (mg/dL) Glucose (mg/dL) Total bilirubin (mg/dL) AST (IU/L) ALT (IU/L) GGT (IU/L) ECG QTc (ms)
9.7 13.8 41.1 253 139 3.7 104 27 14 0.9 117 0.8 42.5 36 32 426
8.8 14.7 42.8 261 139 3.8 103 28 11 0.9 101 0.7 25 24 26 410
1.73 1.33 1.14 0.62 0.41 0.33 0.52 1.46 2.99 2.25 2.38 0.54 3.55 2.26 0.78 1.95
.04 NS NS NS NS NS NS NS .001 .01 .009 NS b.001 .01 NS .03
2.2. Procedures A chart extraction form was developed, which included demographic and clinical variables and whether the patient received emergency IM medication. Emergency IM medications were defined as either antipsychotics or benzodiazepines used for controlling violent or psychotic behavior. The sample was divided into 2 groups—IM- and non– IM-medicated patients. Demographic variables (age, gender, and ethnicity) and common laboratory measurements (complete blood count, serum chemistry, liver function tests, urine drug screen, serum alcohol level, and ECG QTc intervals) were compared between the 2 groups. 2.3. Statistical analysis
GGT indicates g-glutamyl transpeptidase; NS, not significant.
NCSS/PASS 2000 Dawson Edition statistical software (Kaysville, UT, USA) was used for statistical calculations. Mean age values were compared using a 2-tailed t test. Because laboratory variables were less likely to be normally distributed, the Wilcoxon rank sum test was used to compare median values between the IM- and non–IM-medicated patient groups. All dichotomous variables were analyzed using the m2 test. Statistical significance (a) was set to .05. Because multiple variables were tested, the likelihood of detecting significant findings was increased with a relatively high a of .05. Given the pilot study design of this project, however, the investigators felt it was conservatively appropriate for the guidance of future studies with more specific hypothesis testing. 3. Results 3.1. Subjects Two hundred sixty-two charts were requested, of which 247 were available for chart review. Thirty-three patient charts were excluded secondary to age, leaving 214 charts available for data extraction. Thirty-five (16%) patients Table 1 Demographic characteristics of emergently IM- vs non–IM-medicated patients Variable
IM-medicated patients (n = 35)
Non–IMmedicated patients (n = 179)
t/m2
df
P
Age, mean (SD) Male, n (%) Ethnicity, n (%) Hispanic Caucasian Black
42.6 (13.4) 23 (66)
34.3 (11.9) 91 (51)
3.68 2.60 2.65
212 1 2
b.001 NS NS
14 (40) 18 (51) 3 (9)
96 (54) 66 (37) 16 (9)
NS indicates not significant.
received emergency IM medications. Table 1 shows the demographic profiles of IM- and non–IM-medicated patients. Patients receiving emergency IM medications were significantly older than non–IM-medicated patients (42.6 vs 34.3 years, P b.001). There were no significant gender or ethnicity differences. In the IM-medicated patient group, 26 (74%) received a combination of haloperidol and lorazapam, 3 (9%) received haloperidol alone, 5 (14%) received lorazapam alone, and 1 (3%) received a combination of fluphenazine and lorazapam. 3.2. Laboratory values of IM- vs non–IM-medicated patients Patients receiving IM medications had significantly higher WBC count, blood urea nitrogen (BUN), creatinine, glucose, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and ECG QTc interval compared with those who were not emergently medicated (Table 2). Patients receiving emergency IM medications were more likely to have abnormal levels of potassium, glucose, AST, and ALT compared with those who were not emergently medicated (Table 3). 4. Discussion This study is marked by several limitations. It is a pilot study that aims to identify routine laboratory differences between severely agitated IM- and non–IM-medicated patients. Although we did find several differences between these 2 groups, multiple comparisons were made without traditional Bonferroni corrections. Had we made these corrections, our a would be set to .003, leaving only BUN and AST as significant findings. Because this is a pilot study, however, we believe that a set to .05 is conservatively appropriate to guide specific hypothesis testing in future studies.
T.L. Schillerstrom et al. / General Hospital Psychiatry 26 (2004) 411 – 414
413
Table 3 Prevalence of abnormal laboratory values in IM- vs non–IM-medicated patients Laboratory
Reference range
WBC (cells per AL) Hemoglobin (g/dL) Hematocrit (cells per AL) Platelets (cells per AL) Sodium (mmol/L) Potassium (mmol/L) Chloride (mmol/L) Bicarbonate (mmol/L) BUN (mg/dL) Creatinine (mg/dL) Glucose (mg/dL) Total bilirubin (mg/dL) AST (IU/L) ALT (IU/L) GGT (IU/L) Alcohol Drug screen ECG QTc (ms)
3.6-11 12-16 36-46 150-450 135-148 3.4-5.0 95-110 18-30 5-22 0.5-1.3 60-110 0.2-1.2 11-36 6-31 6-45 none none b500
IM-medicated patients
Non–IM-medicated patients
n
%
n
%
9/33 3/33 6/33 2/33 5/33 10/33 1/33 4/33 2/33 2/33 17/33 5/30 20/32 17/32 11/31 8/29 12/25 1/6
27 9 18 6 15 30 3 12 6 6 52 17 63 53 35 23 48 17
18/129 25/130 36/130 6/128 12/133 17/134 3/131 21/132 5/134 3/134 40/133 24/125 34/129 44/129 34/125 27/114 54/121 1/42
14 19 28 5 9 13 2 16 4 2 30 19 26 34 27 24 45 2
m21
P
3.36 1.90 1.27 0.10 0.98 6.06 0.09 0.29 0.29 1.33 5.39 0.10 15.03 3.94 0.83 0.19 0.10 2.68
NS NS NS NS NS b.05 NS NS NS NS b.05 NS b.001 b.05 NS NS NS NS
See Table 2 legend.
In addition, according to the 214 subjects’ charts reviewed, not all subjects had the same laboratories ordered and not all had laboratories drawn. Electrocardiograms in particular were seldom ordered. Hence, there are missing data. This problem is related to the retrospective design of the study. While a prospective design is ideal, it would be difficult to accomplish given the issue of informed consent in this acutely ill population. Our goal was to report routine laboratory findings of typical patients emergently medicated in a PES. We believe this sample is representative of patients routinely seen in this PES. This is a resident-run service, however, which may not be reflective of other services nationally. We also collected data over a relatively short period—1 month. It is possible that the psychiatry residents rotating through the PES during this time may have been either more or less likely to emergently medicate patients. The month of April was specifically chosen because it is later in the academic year and residents are better able to identify situations requiring the use of emergency medications. Collecting data for more than several months would have adjusted for resident bias as well as increased the overall power of the study. Regardless, this pilot study’s results will be of interest to clinicians who practice emergency psychiatry. To begin with, IM-medicated patients were significantly older than non–IM-medicated patients. This may be because younger patients have not yet engaged in mental health services and are seeking help that is better managed with outpatient referrals. Older patients seen in a PES may be more likely to be suffering from acute decompensation of chronic mental illness. Although the age difference was not great, early 40s compared with the mid-30s, it may have contributed to some of the observed laboratory
differences. In addition, IM-medicated patients were not more likely to test positive for alcohol or other substances, which are 2 predictors of violence in patients with mental illness [6,7]. Patients receiving emergency IM medications were more likely to have higher WBC count, BUN, creatinine, AST, ALT, serum glucose, and ECG QTc interval and were more likely to have abnormal levels of potassium, glucose, AST, and ALT. Other investigators have also reported impaired glucose tolerance, hypokalemia, and cardiac conduction abnormalities in patients with mental illness [8–11]. Our findings could have resulted either from clinically minor causes, such as dehydration and demargination, or from more serious causes, such as renal or liver disease. We did not attempt to identify the etiology of the laboratory findings. Although these laboratory findings may not be clinically significant when considered individually, they could act synergistically to increase the risk of medical complications, particularly with regard to cardiac arrhythmia. High rates of cardiovascular disease risk factors, as previously reported, combined with dehydration, as suggested by elevated BUN, and hypokalemia, as reported in this study, may synergistically act to lengthen QTc intervals [12]. Medications that prolong the QTc interval may further enhance this effect when used to control agitated and psychotic behavior. In summary, we found several laboratory differences between agitated patients who are receiving emergency IM medications and those who are not. These findings suggest that agitated patients may be medically different from nonagitated patients from the outset. It is our impression that these differences, which may be clinically important, are underrecognized.
414
T.L. Schillerstrom et al. / General Hospital Psychiatry 26 (2004) 411 – 414
References [1] Lindenmayer JP, Czobor P, Volavka J, et al. Changes in glucose and cholesterol levels in patients with schizophrenia treated with typical or atypical antipsychotics. Am J Psychiatry 2003;160:290 – 6. [2] Hunt N, Stern TA. The association between intravenous haloperidol and Torsades de Pointes. Three cases and a literature review. Psychosomatics 1995;36:541 – 9. [3] Hedenmalm K, Hagg S, Stahl M, Mortimer O, Spigset O. Glucose intolerance with atypical antipsychotics. Drug Saf 2002;25:1107 – 16. [4] Wilson DR, D’Souza L, Sarkar N, Newton M, Hammond C. Newonset diabetes and ketoacidosis with atypical antipsychotics. Schizophr Res 2003;59:1 – 6. [5] Glassman AH, Bigger Jr JT. Antipsychotic drugs: prolonged QTc interval, torsade de pointes, and sudden death. Am J Psychiatry 2001;158:1774 – 82. [6] Steadman HJ, Mulvey EP, Monahan J, et al. Violence by people discharged from acute psychiatric inpatient facilities and by others in the same neighborhoods. Arch Gen Psychiatry 1998;55:393 – 401.
[7] Soliman AE, Reza H. Risk factors and correlates of violence among acutely ill adult psychiatric inpatients. Psychiatr Serv 2001; 52:75 – 80. [8] Regenold WT, Thapar RK, Marano C, Gavirneni S, Kondapavuluru PV. Increased prevalence of type 2 diabetes mellitus among psychiatric inpatients with bipolar I affective and schizoaffective disorders independent of psychotropic drug use. J Affect Disord 2002;70:19 – 26. [9] Subramaniam M, Chong SA, Pek E. Diabetes mellitus and impaired glucose tolerance in patients with schizophrenia. Can J Psychiatry 2003;48:345 – 7. [10] Hatta K, Takahashi T, Nakamura H, et al. Prolonged QT interval in acute psychotic patients. Psychiatry Res 2000;94:279 – 85. [11] Hollister LE. Electrocardiographic screening in psychiatric patients. J Clin Psychiatry 1995;56:26 – 9. [12] Davidson S, Judd F, Jolley D, et al. Cardiovascular risk factors for people with mental illness. Aust N Z J Psychiatry 2001;35: 196 – 202.
Laboratory findings in emergently medicated psychiatry patientsB Tracy L. Schillerstrom, M.D.*, Jason E. Schillerstrom, M.D., Sally E. Taylor, M.D. Department of Psychiatry, The University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA Received 18 December 2003; accepted 29 June 2004
Abstract Objective: To determine routine laboratory differences between patients with severe psychomotor agitation who require emergency intramuscular (IM-medicated patients) medication and those who do not (non–IM-medicated patients). Method: A retrospective chart review of patients 18 years or older who went to a psychiatry emergency service over a 30-day period was performed. Demographic and laboratory variables were compared between IM- and non–IM-medicated patients. Results: Emergently medicated patients (n = 35) were older than non–IM-medicated patients (n = 179) (42.6 vs 34.3 years, P b.001). Patients receiving emergency IM medications had higher leukocyte (WBC) count ( P = .04), blood urea nitrogen ( P = .001), creatinine ( P = .01), glucose ( P = .009), aspartate aminotransferase ( P b.001), alanine aminotransferase ( P = .01), and electrocardiogram QTc interval ( P = .03). They were also more likely to have abnormal levels of potassium ( P b.05), glucose ( P b.05), aspartate aminotransferase ( P b.001), and alanine aminotransferase ( P b.05). Conclusions: Emergently medicated patients in this psychiatry emergency service were more likely to be older and more likely to have abnormal laboratories vs other adult patients. D 2004 Elsevier Inc. All rights reserved.
1. Introduction Patients with severe psychomotor agitation evaluated by a psychiatry emergency service (PES) often require emergency intramuscular (IM) medications to manage violent behaviors. For safety reasons, these patients are sometimes medicated before the completion of a medical history and laboratory studies. The medications used can have serious medical side effects. For example, haloperidol has been associated with elevated glucose levels and increased corrected electrocardiogram (ECG) QTc interval [1,2]. Atypical antipsychotics, now being marketed for emergency use, can also affect glucose metabolism and cardiac conduction [1,3–5]. It is our impression that a widely held assumption is that there are no medical differences between agitated and nonagitated psychiatry patients. Baseline medical differences between agitated and nonagitated patients in actual B
No funding was used or solicited for this work. * Corresponding author. Tel.: +1 210 567 5430; fax: +1 210 567 6941. E-mail address: [email protected] (T.L. Schillerstrom). 0163-8343/$ – see front matter D 2004 Elsevier Inc. All rights reserved. doi:10.1016/j.genhosppsych.2004.06.004
clinical practice have not been previously reported. Severely agitated patients may be more medically vulnerable than nonagitated patients. This pilot study aims to identify laboratory differences between severely agitated psychiatry patients who require emergency IM medication (IMmedicated patients) and those who do not (non–IMmedicated patients).
2. Methods 2.1. Subjects and setting Institutional Review Board approval for this study was obtained from The University of Texas Health Science Center at San Antonio before data collection. A retrospective chart review of all patients 18 years or older who went to a PES in a large public hospital was performed. Consecutive charts of patients evaluated between April 1, 2002, and April 30, 2002, were reviewed. The PES is a 5-room/5-bed center separate from the medical emergency center. It is staffed 24 hours per day by rotating psychiatry residents. On-site faculty supervision is
412
T.L. Schillerstrom et al. / General Hospital Psychiatry 26 (2004) 411 – 414
present 14 hours per day. The nursing and support staff are specifically trained in the treatment and management of persons with severe mental illness.
Table 2 Median laboratory values of IM- vs non–IM-medicated patients Laboratory
IM-medicated patients
Non–IMmedicated patients
Z
P
WBC (cells per AL) Hemoglobin (g/dL) Hematocrit (cells per AL) Platelets (cells per AL) Sodium (mmol/L) Potassium (mmol/L) Chloride (mmol/L) Bicarbonate (mmol/L) BUN (mg/dL) Creatinine (mg/dL) Glucose (mg/dL) Total bilirubin (mg/dL) AST (IU/L) ALT (IU/L) GGT (IU/L) ECG QTc (ms)
9.7 13.8 41.1 253 139 3.7 104 27 14 0.9 117 0.8 42.5 36 32 426
8.8 14.7 42.8 261 139 3.8 103 28 11 0.9 101 0.7 25 24 26 410
1.73 1.33 1.14 0.62 0.41 0.33 0.52 1.46 2.99 2.25 2.38 0.54 3.55 2.26 0.78 1.95
.04 NS NS NS NS NS NS NS .001 .01 .009 NS b.001 .01 NS .03
2.2. Procedures A chart extraction form was developed, which included demographic and clinical variables and whether the patient received emergency IM medication. Emergency IM medications were defined as either antipsychotics or benzodiazepines used for controlling violent or psychotic behavior. The sample was divided into 2 groups—IM- and non– IM-medicated patients. Demographic variables (age, gender, and ethnicity) and common laboratory measurements (complete blood count, serum chemistry, liver function tests, urine drug screen, serum alcohol level, and ECG QTc intervals) were compared between the 2 groups. 2.3. Statistical analysis
GGT indicates g-glutamyl transpeptidase; NS, not significant.
NCSS/PASS 2000 Dawson Edition statistical software (Kaysville, UT, USA) was used for statistical calculations. Mean age values were compared using a 2-tailed t test. Because laboratory variables were less likely to be normally distributed, the Wilcoxon rank sum test was used to compare median values between the IM- and non–IM-medicated patient groups. All dichotomous variables were analyzed using the m2 test. Statistical significance (a) was set to .05. Because multiple variables were tested, the likelihood of detecting significant findings was increased with a relatively high a of .05. Given the pilot study design of this project, however, the investigators felt it was conservatively appropriate for the guidance of future studies with more specific hypothesis testing. 3. Results 3.1. Subjects Two hundred sixty-two charts were requested, of which 247 were available for chart review. Thirty-three patient charts were excluded secondary to age, leaving 214 charts available for data extraction. Thirty-five (16%) patients Table 1 Demographic characteristics of emergently IM- vs non–IM-medicated patients Variable
IM-medicated patients (n = 35)
Non–IMmedicated patients (n = 179)
t/m2
df
P
Age, mean (SD) Male, n (%) Ethnicity, n (%) Hispanic Caucasian Black
42.6 (13.4) 23 (66)
34.3 (11.9) 91 (51)
3.68 2.60 2.65
212 1 2
b.001 NS NS
14 (40) 18 (51) 3 (9)
96 (54) 66 (37) 16 (9)
NS indicates not significant.
received emergency IM medications. Table 1 shows the demographic profiles of IM- and non–IM-medicated patients. Patients receiving emergency IM medications were significantly older than non–IM-medicated patients (42.6 vs 34.3 years, P b.001). There were no significant gender or ethnicity differences. In the IM-medicated patient group, 26 (74%) received a combination of haloperidol and lorazapam, 3 (9%) received haloperidol alone, 5 (14%) received lorazapam alone, and 1 (3%) received a combination of fluphenazine and lorazapam. 3.2. Laboratory values of IM- vs non–IM-medicated patients Patients receiving IM medications had significantly higher WBC count, blood urea nitrogen (BUN), creatinine, glucose, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and ECG QTc interval compared with those who were not emergently medicated (Table 2). Patients receiving emergency IM medications were more likely to have abnormal levels of potassium, glucose, AST, and ALT compared with those who were not emergently medicated (Table 3). 4. Discussion This study is marked by several limitations. It is a pilot study that aims to identify routine laboratory differences between severely agitated IM- and non–IM-medicated patients. Although we did find several differences between these 2 groups, multiple comparisons were made without traditional Bonferroni corrections. Had we made these corrections, our a would be set to .003, leaving only BUN and AST as significant findings. Because this is a pilot study, however, we believe that a set to .05 is conservatively appropriate to guide specific hypothesis testing in future studies.
T.L. Schillerstrom et al. / General Hospital Psychiatry 26 (2004) 411 – 414
413
Table 3 Prevalence of abnormal laboratory values in IM- vs non–IM-medicated patients Laboratory
Reference range
WBC (cells per AL) Hemoglobin (g/dL) Hematocrit (cells per AL) Platelets (cells per AL) Sodium (mmol/L) Potassium (mmol/L) Chloride (mmol/L) Bicarbonate (mmol/L) BUN (mg/dL) Creatinine (mg/dL) Glucose (mg/dL) Total bilirubin (mg/dL) AST (IU/L) ALT (IU/L) GGT (IU/L) Alcohol Drug screen ECG QTc (ms)
3.6-11 12-16 36-46 150-450 135-148 3.4-5.0 95-110 18-30 5-22 0.5-1.3 60-110 0.2-1.2 11-36 6-31 6-45 none none b500
IM-medicated patients
Non–IM-medicated patients
n
%
n
%
9/33 3/33 6/33 2/33 5/33 10/33 1/33 4/33 2/33 2/33 17/33 5/30 20/32 17/32 11/31 8/29 12/25 1/6
27 9 18 6 15 30 3 12 6 6 52 17 63 53 35 23 48 17
18/129 25/130 36/130 6/128 12/133 17/134 3/131 21/132 5/134 3/134 40/133 24/125 34/129 44/129 34/125 27/114 54/121 1/42
14 19 28 5 9 13 2 16 4 2 30 19 26 34 27 24 45 2
m21
P
3.36 1.90 1.27 0.10 0.98 6.06 0.09 0.29 0.29 1.33 5.39 0.10 15.03 3.94 0.83 0.19 0.10 2.68
NS NS NS NS NS b.05 NS NS NS NS b.05 NS b.001 b.05 NS NS NS NS
See Table 2 legend.
In addition, according to the 214 subjects’ charts reviewed, not all subjects had the same laboratories ordered and not all had laboratories drawn. Electrocardiograms in particular were seldom ordered. Hence, there are missing data. This problem is related to the retrospective design of the study. While a prospective design is ideal, it would be difficult to accomplish given the issue of informed consent in this acutely ill population. Our goal was to report routine laboratory findings of typical patients emergently medicated in a PES. We believe this sample is representative of patients routinely seen in this PES. This is a resident-run service, however, which may not be reflective of other services nationally. We also collected data over a relatively short period—1 month. It is possible that the psychiatry residents rotating through the PES during this time may have been either more or less likely to emergently medicate patients. The month of April was specifically chosen because it is later in the academic year and residents are better able to identify situations requiring the use of emergency medications. Collecting data for more than several months would have adjusted for resident bias as well as increased the overall power of the study. Regardless, this pilot study’s results will be of interest to clinicians who practice emergency psychiatry. To begin with, IM-medicated patients were significantly older than non–IM-medicated patients. This may be because younger patients have not yet engaged in mental health services and are seeking help that is better managed with outpatient referrals. Older patients seen in a PES may be more likely to be suffering from acute decompensation of chronic mental illness. Although the age difference was not great, early 40s compared with the mid-30s, it may have contributed to some of the observed laboratory
differences. In addition, IM-medicated patients were not more likely to test positive for alcohol or other substances, which are 2 predictors of violence in patients with mental illness [6,7]. Patients receiving emergency IM medications were more likely to have higher WBC count, BUN, creatinine, AST, ALT, serum glucose, and ECG QTc interval and were more likely to have abnormal levels of potassium, glucose, AST, and ALT. Other investigators have also reported impaired glucose tolerance, hypokalemia, and cardiac conduction abnormalities in patients with mental illness [8–11]. Our findings could have resulted either from clinically minor causes, such as dehydration and demargination, or from more serious causes, such as renal or liver disease. We did not attempt to identify the etiology of the laboratory findings. Although these laboratory findings may not be clinically significant when considered individually, they could act synergistically to increase the risk of medical complications, particularly with regard to cardiac arrhythmia. High rates of cardiovascular disease risk factors, as previously reported, combined with dehydration, as suggested by elevated BUN, and hypokalemia, as reported in this study, may synergistically act to lengthen QTc intervals [12]. Medications that prolong the QTc interval may further enhance this effect when used to control agitated and psychotic behavior. In summary, we found several laboratory differences between agitated patients who are receiving emergency IM medications and those who are not. These findings suggest that agitated patients may be medically different from nonagitated patients from the outset. It is our impression that these differences, which may be clinically important, are underrecognized.
414
T.L. Schillerstrom et al. / General Hospital Psychiatry 26 (2004) 411 – 414
References [1] Lindenmayer JP, Czobor P, Volavka J, et al. Changes in glucose and cholesterol levels in patients with schizophrenia treated with typical or atypical antipsychotics. Am J Psychiatry 2003;160:290 – 6. [2] Hunt N, Stern TA. The association between intravenous haloperidol and Torsades de Pointes. Three cases and a literature review. Psychosomatics 1995;36:541 – 9. [3] Hedenmalm K, Hagg S, Stahl M, Mortimer O, Spigset O. Glucose intolerance with atypical antipsychotics. Drug Saf 2002;25:1107 – 16. [4] Wilson DR, D’Souza L, Sarkar N, Newton M, Hammond C. Newonset diabetes and ketoacidosis with atypical antipsychotics. Schizophr Res 2003;59:1 – 6. [5] Glassman AH, Bigger Jr JT. Antipsychotic drugs: prolonged QTc interval, torsade de pointes, and sudden death. Am J Psychiatry 2001;158:1774 – 82. [6] Steadman HJ, Mulvey EP, Monahan J, et al. Violence by people discharged from acute psychiatric inpatient facilities and by others in the same neighborhoods. Arch Gen Psychiatry 1998;55:393 – 401.
[7] Soliman AE, Reza H. Risk factors and correlates of violence among acutely ill adult psychiatric inpatients. Psychiatr Serv 2001; 52:75 – 80. [8] Regenold WT, Thapar RK, Marano C, Gavirneni S, Kondapavuluru PV. Increased prevalence of type 2 diabetes mellitus among psychiatric inpatients with bipolar I affective and schizoaffective disorders independent of psychotropic drug use. J Affect Disord 2002;70:19 – 26. [9] Subramaniam M, Chong SA, Pek E. Diabetes mellitus and impaired glucose tolerance in patients with schizophrenia. Can J Psychiatry 2003;48:345 – 7. [10] Hatta K, Takahashi T, Nakamura H, et al. Prolonged QT interval in acute psychotic patients. Psychiatry Res 2000;94:279 – 85. [11] Hollister LE. Electrocardiographic screening in psychiatric patients. J Clin Psychiatry 1995;56:26 – 9. [12] Davidson S, Judd F, Jolley D, et al. Cardiovascular risk factors for people with mental illness. Aust N Z J Psychiatry 2001;35: 196 – 202.