DISSERTATION FOR M MED PSYCHIATRY

TITLE: PSYCHIATRIC CONSULTATION-LIAISON

AT DR GEORGE MUKHARI HOSPITAL

IN GARANKUWA

BETWEEN JANUARY – DECEMBER 2009

RESEARCHER: DR N PILLAY

MBChB (UKZN)

STUDENT NUMBER: 200729248

SUPERVISOR: PROFESSOR S.T RATAEMANE

HOD: DEPARTMENT OF PSYCHIATRY

MBChB (NATAL) FC PSYCH (SA)

DIPL. CHILD PSYCHIATRY (LONDON)

CO-SUPERVISOR: DR P.S MAZIBUKO

MBChB (MEDUNSA) FC PSYCH (SA)

PSYCHIATRIC CONSULTATION-LIAISON AT DR GEORGE MUKHARI HOSPITAL IN GARANKUWA BETWEEN JANUARY – DECEMBER 2009

By

Dr Nivendhiren Pillay

Submitted in partial fulfilment of requirements for the Degree of Masters of Medicine in the Department of Psychiatry at the University of Limpopo, Medunsa campus

18 August 2010

Supervisor: Professor ST Rataemane MBChB (Natal), FCPsych (SA), Dipl. Child Psych (London)

Co-supervisor: Dr P.S Mazibuko MBChB (Medunsa), FCPsych (SA)

DECLARATION

I, Nivendhiren Pillay hereby declare that the work on which this research is based is original (except where acknowledgements indicate otherwise) and that neither the whole work nor any part of it has been, is being or is to be submitted for another degree at this or any other university.

Signed at the University of Limpopo on the 18th August 2010

Dr Nivendhiren Pillay

……………………..

Acknowledgements

I would like to acknowledge the support and encouragement of my supervisors, Professor Rataemane, and Dr Mazibuko. Thank you for your valuable assistance and motivation.

I would also like to thank my parents for their encouragement.

Thanks to God for his all blessings

Dedication

I dedicate this to my wife Michelle. Thank you for all the support you have given me over these last few years. You have been a pillar of strength to me. And to our beautiful baby girl, Ketana, thank you for entering into our lives and making it more fulfilling.
TABLE OF CONTENTS

Abstract …………………………………………………………….….…7

CHAPTER 1………………………………………………………………………..….8

INTRODUCTION……………………………………………………………………..8

CHAPTER 2…………………………………………………………………………..11

LITERATURE REVIEW…………………………………………………………......11

CHAPTER 3…………………………………………………………………………..15

METHODOLOGY…………………………………………………………………....15

Aims…………………………………………………………………………………...15

Objectives………………………………………………………………………….….15

Study design……………………………………………………………………..…….15

Sample…………………………………………………………………………….…....16

Data collection & Data analysis………………………………………………….….…17

Reliability & validity…………………………………………………………….….….18

CHAPTER 4…………………………………………………………………….….….19

RESULTS……………………………………………………………………….……..19

CHAPTER 5…………………………………………………………………….…...…26

DISCUSSION……………………………………………………………………..…...26

CHAPTER 6………………………………………………………………………..…..29

CONCLUSION…………………………………………………………………..…….29

LIMITATIONS……………………………………………………………………..….30

RECOMMENDATIONS………………………………………………………………30

REFERENCES…………………………………………………………………………31

ABSTRACT

The aim of the study was to establish a profile of psychiatric illnesses that are encountered during consultation-liaison (C-L) psychiatry and to describe interventions undertaken. The objective was to identify referral patterns, establish the referral rate, and to profile the diagnoses & describe the actions taken by the consulting doctor. This was a retrospective cross-sectional descriptive study conducted on all inpatients that were referred to psychiatry from other disciplines in the hospital for the 12 month period January to December 2009. The study was conducted at Dr George Mukhari Hospital, which is a tertiary psychiatric unit which caters for mental health care users in the Garankuwa , Soshanguve and Mabopane region.

The study found that the referral rate to psychiatric C-L services was lower than at other institutions. Amongst the referred patients, there was a high incidence of organic brain syndrome diagnoses, but a low rate of depression.

The study proposed further investigation into the reasons behind the low rate of referral and low rate of depression, so as to improve C-L service delivery in the hospital.

CHAPTER ONE

INTRODUCTION

Comorbid psychiatric illness in general medical patients is common. Silverstone (1996: 43), performed semi-structured psychiatric interviews on 313 consecutively admitted medical inpatients & found that 27,2% met DSM IV criteria for a psychiatric disorder. Even higher rates were reported by Fulop et al (1998: 273), who prospectively interviewed 467 geriatric medical & surgical admissions & found 208 patients (44,5%) to have met DSM-III-R criteria for a psychiatric disorder.

In Africa, Ndetei et al (2009:859) conducted a cross sectional survey among 10 health facilities in Kenya and found there to be a high incidence of depression (42,3%) among medical patients not previously diagnosed with a psychiatric disorder.

In South Africa, the South African Stress and Health (SASH) study found the lifetime prevalence for an individual to have any mental disorder in South Africa to be 30,3%, with anxiety disorders being the most prevalent, followed by substance use disorders and mood disorders (Herman et al , 2009: 339)

In the hospital setting, MG Nair and SS Pillay (1997: 144) did a prospective study that involved interviews with 230 patients in a Durban hospital. Their findings revealed that 21% of the patients had a psychiatric disorder according to DSM-III-R, with substance dependence & depression being the most common.

Psychiatric comorbidities are common in medically ill patients, but what is also true is that medical illnesses are common in psychiatric patients. Studies have found higher than average rates of physical illness amongst psychiatric patients. Beyer et al (2005: 401) found high rates of hypertension, cardiovascular disorders, asthma, diabetes and HIV amongst individuals with bipolar disorder. Cournos, McKinnon, Sullivan (2005: 27) found that schizophrenics have higher than average rates of HIV and hepatitis C due to substance abuse, vulnerability to sexual victimisation and positive symptoms of psychosis. This may also explain why there is such a high percentage of psychiatric disorders that are seen among medical inpatients.

From the above it is clear that there is a high incidence of psychiatric illness among general hospital patients, but what is of concern is that the rate of referral to psychiatry is only in the region of 0,9-4,2% (Diefenbacher,A., Strain,J.J., 2002:249; de Jonge, P., 2001:152; Kishi,Y., 2007: 517; Clark,D.M., Smith,G.C., 1995:424;

Gangat,A.E., Naidoo, L.R., Simpson, M.A., 1987:853). It is the researcher’s opinion that this probably means that the majority of patients with psychiatric comorbities are not detected and thus are inadequately treated.

Psychiatric conditions in medically ill patients are recognised as a major risk factor for poorer treatment outcomes, longer length of stay (LOS) in hospital, and increased re-hospitalisation, thus consuming greater healthcare resources when compared to medically ill patients without psychiatric comorbidity (Diefenbacher A., Strain, J.J., 2002:249). Bourgeois et al (2005: 431) looked at the impact of psychiatric diagnosis on LOS at a major university medical centre. Patients with comorbid psychiatric disorders represented 33-35% of the total cases. They consistently found that, over the 3 year period of the study, comorbid psychiatric illness increased the LOS for patients. Furlanetto, da Silva and Bueno (2003:14), in a Brazilian study did a prospective cohort study on a series of 317 medical inpatients consecutively admitted to the general medical wards of a university hospital, and found that patients with organic brain syndrome (delirium & dementia), had a prolonged length of stay as compared to other patients

The researcher will attempt to establish the pattern of inpatient referral to the consultation-liaison (C-L) psychiatry service in the hospital.

The study objectives were:

To identify referral patterns, that is, which departments refer most frequently & what are the reasons for referral

To establish the referral rate to C-L psychiatric services

To create a diagnostic profile of patients seen during C-L psychiatry

To describe the interventions undertaken by the assessing doctor

CHAPTER TWO

LITERATURE REVIEW

Diefenbacher & Strain (2002: 249) observed changes to a C-L psychiatry service at the Mount Sinai Medical Centre, New York between 1988 to 1997. They had 4429 referrals, with a consultation rate to psychiatry in the region of 0,9 – 1,7% during the study period. They found that an average of 50,3% of referrals were from internal medicine, infectious diseases or nephrology, 19,2% from surgery, orthopaedics, ENT, neurosurgery and cardiac surgery; 2,9% from transplantation services, 5,4 % from neurology and 4,4% from obstetrics and gynaecology. The reasons for referral were “depression” (12,6 – 18,3%), “behaviour management / agitation” (8,3 – 13,3%), “judgement / informed consent / against medical advice” (6,9 – 11,1 %) and “suicide risk / attempt assessment” (5,8 – 10,1%). Delirium, followed by dementia and substance induced disorder accounted for majority of diagnoses (40,1%). Depressive disorders, including Adjustment disorder with depressed mood (28,1%) formed the 2nd largest group. Substance use disorders were 3rd highest (8,5%). They found an increasing trend in the prescription of psychotropic drugs (39,1- 49,2%), and also an increase in the number of patients having to be transferred to an inpatient psychiatry ward (2,2 - 14,5%).

In another study de Jonge et al (2001: 152) studied the referral of neurology inpatients to psychiatric C-L services in 33 European hospitals using data obtained from the European Consultation Liaison Workgroup Collaborative Study (Huyse et al, 2001:124). They compared these to referrals from other wards. The sample consisted of 9340 C-L referrals. They found that the referral rate was 1.8%, similar to reports in other studies (Diefenbacher,A., Strain,J.J., 2002:249; Gangat, A.E.,Naidoo, L.R., Simpson, M.A., 1987:853). 8% of all psychiatric consults were from neurology. The most frequent conditions diagnosed were organic mental disorders (19,8%), anxiety (15,5%), and mood disorders (15,1%). The commonest diagnoses for patients referred from non-neurology wards were anxiety (19,6%), mood disorders (18,8%) and substance abuse (11,9%).

Bourgeois et al (2005: 431) analysed referrals to C-L psychiatry at the University of California, Davis Medical Centre. Their study sample consisted of 901 patients referred over a one year period with a referral rate of 4,2%. Mood disorders (40,7%) formed the majority of diagnoses made, followed by cognitive disorders (32%) & substance use disorders (18,6%). Patients who were consulted had a mean length of stay of 8 days, compared to 3 days for other patients who were admitted.

Rothenhausler et al (2008: 301) looked at the pattern of psychiatric referrals in an Austrian tertiary care centre. They assessed 3307 referrals over a 2 year period & compared the 1st year to the 2nd year. They found that the referral rate increased to 3,3% in the 2nd year. Over both years, majority of referrals were from internal medicine (31%). The most common psychiatric diagnoses over the two years were adjustment disorders (23%) followed by delirium (18,4%), and depressive disorders (16,4%). Pharmacotherapy was the most frequent action in both surveys and accounted for between 45-49% of all actions.

Yasuhiro Kishi et al (2007: 517) did a cross-national study in which they compared C-L psychiatric services between a hospital in Minnesota USA, and a hospital in Kanagawa, Japan. In the Minnesota hospital the rate of referral to psychiatry was 3,1% and in Kanagawa it was 2,4%. The most common reason for referral was depression (35,4%), chemical dependency (27,5%), suicidal concerns (11,5%) and confusion/delirium (8,2%) in Minnesota. In Kanagawa, the reasons were “for evaluation” (34,1%), confusion/delirium (27,1%), anxiety (21,1%), and depression (19%). The most common diagnosis made in the Minnesota hospital was that of depression (54,7) %, followed by alcohol related disorders (24,9%), delirium (19%), anxiety disorders & other drug related disorders (13,7%). In Kanagawa it was delirium (21,8%), followed by depression (19,5%), adjustment disorders (8,8%) and anxiety disorder (9,3%).

In an Australian study, Clark DM & Smith GC (1995: 424) looked at 165 consecutive referrals to psychiatry over a 12 month period. The referral rate was 4,2%. There was an association between psychiatric referral and prolonged length of stay (18 days for referred patients, 9 days for non referred patients). The most common reasons for referral were depression, suicide risk assessment, organic brain syndromes, and “psychological component to illness”. The most common diagnoses were mood disorders (55%), organic mental disorders (35%), adjustment disorders (19%), somatoform disorders (16%), and personality disorders (15%)

In a South African study Gangat, Naidoo, and Simpson (1987: 853) looked at a sample of 597 patients referred to C-L psychiatry at Addington Hospital in Durban. The referral rate was 1,8%. 70% of the inpatients were from internal medicine, 18% from surgery & allied departments & 4% were from obstetrics & gynaecology. The most common reasons for referral were found to be parasuicide (24%), depression (13%), abnormal behaviour (11%), & problems of alcohol abuse (7%). The most common diagnoses made were depressive disorder (33%), neuroses (14,7%) and drug dependence & alcoholism (12,1%). In 38% of cases, medication was used, and in 18% of cases, psychotherapy was offered. 7.5% of referred patients needed transfer to a psychiatric ward.

CHAPTER THREE

METHODOLOGY

AIM

To establish a profile of psychiatric illnesses that is encountered during C-L psychiatry and to describe interventions undertaken.

OBJECTIVES

To identify referral patterns, that is, which departments refer most frequently & what are the reasons for referral

To establish the referral rate to C-L psychiatric services

To create a diagnostic profile of patients seen during C-L psychiatry

To describe the interventions undertaken by the assessing doctor

STUDY DESIGN

This was a retrospective cross-sectional descriptive study conducted on all inpatients that were referred to psychiatry from non psychiatric wards (medical, surgical, orthopaedic etc) during the period from January – December 2009.

STUDY POPULATION

The study population was all the inpatients that were referred to C-L psychiatry from non psychiatric disciplines during the period of the study.

SAMPLE

The sample included all patients seen by the C-L psychiatric service for the period of the study.

DATA COLLECTION

When a doctor refers a patient to psychiatry he/she fills an interdisciplinary consultation form (ICF), in duplicate, which is then left at the psychiatric outpatient department. For each month a different psychiatry registrar is assigned to the C-L rotation and attends to the patients referred. Patients are evaluated & the diagnosis & management are documented on the same form. The researcher analysed information using a duplicate of the ICF (see attached), to obtain information which will then be transferred to a data collection sheet.

The “Data Collection Sheet” (see attached) comprised the following sections as outlined below:

Demographic Data: included parameters of age & gender

Source of referral : identified the department that referred the patient

Reason for referral: established why the patient was referred.

Past psychiatric history : was used to ascertain whether the patient was known to have psychiatric problems before coming to hospital

Current Psychiatric and Medical diagnoses: was the psychiatric diagnosis made by the C-L registrar, according to the DSM-IV-TR (diagnostic and statistical manual of mental disorders- 4th edition- text revision), and the physical illness for which he/she was being treated for by the referring team.

Interventions: the recommendations made by the C-L psychiatry registrar including biological treatment, investigations and psychosocial interventions. Also, the long term plan if any (such as outpatient follow up etc )

DATA ANALYSIS

A qualitative and quantitative analysis of the data was performed using results obtained from the data sheet. The data was entered into an electronic database. Data entry was verified and validation checks were performed. Epi Info Version 6.04 was used for the analysis. The analysis was done by the researcher in collaboration with the biostatistician at Medunsa. Percentage responses in the various categories were calculated with 95% confidence intervals as appropriate. Cross tabulations as appropriate were done and analysed by chi-squared methods

RELIABILITY AND VALIDITY

Reliability

Information on the consultation form is assumed to be as accurate as possible as these are legal documents. Furthermore, information on these forms is usually verified with the information in patient’s files when the patient is seen in the ward. The forms are filled in duplicate to ensure that one copy remains in the patient’s file and one is kept in the psychiatry department, hence information can be traced easily.

Validity

As the study is being conducted in a training hospital, registrar’s in both the referring department and the psychiatric department are always under the supervision of their consultants in terms of their diagnoses and management of patients. Psychiatric diagnoses are further standardised by the DSM-IV-TR criteria for psychiatric diagnosis which is internationally recognized. The above measures will ensure validity is maintained.

Bias

There was no selection bias because all patients referred to psychiatry for consultation from other wards during the study period were included. Detection bias was minimal due to the comprehensive method of arriving at the diagnosis. However, there may be some degree of bias because patients referred at outpatient level were not considered in the study.

CHAPTER FOUR

RESULTS

For the 12 month period January to December 2009, 74 patients were referred to the consultation-liaison psychiatric services in the hospital. This was in spite of admissions of 41913 patients for the departments that referred, meaning an overall referral rate to psychiatry of 0,17%.

There were 46 females (62%) and 28 males (38%) referred. The mean age of referral was 40 years (see graph 1)

GRAPH 1

The most common reasons for referral were aggression/behavioural problem (24,7%), followed by “psychosis” (23,8%), “known” mental health care user (13,5%), confusion (11,8%), parasuicide (9,5%), depression (7,9%), and drug abuse (4,8%) (see graph 2)

GRAPH 2

The department that referred most frequently was internal medicine & its allied departments (cardiology, neurology, family medicine) (51%), followed by surgery & its allied departments (neurosurgery, urology, ENT, orthopaedics) (32,4%), and obstetrics & gynaecology (11%)

(see graph 3)

GRAPH 3

The most common conditions that patients that were referred were being treated primarily for were trauma/fracture 18%, HIV related conditions 15%, TB pneumonia 15%, post delivery 11%, epilepsy 8%, parasuicide & cardiac disease 7%. (see graph 4)

GRAPH 4

25% of referred patients had a past history of psychiatric illness.

In terms of the diagnoses made, 30% received a diagnosis of an organic brain syndrome (delirium/dementia), 27% of patients received a diagnosis of psychosis due to general medical condition, 15% had schizophrenia, 5% had major depressive disorder & 4% had substance abuse. (see graph 5)

GRAPH 5

The most frequent actions taken by the consulting doctor were: pharmacotherapy 95%, referred to psychologist 20%, referred to social worker 5%

36% of patients were given a follow up appointment in the psychiatry outpatients department & 8% were transferred to the psychiatric ward from the referring ward (see graph 6)

GRAPH 6

The most frequent psychoanaleptics ordered for patients was Haloperidol 33,7%, benzodiazepines 18,9%, Risperidone 18%, SSRI’s & Epilim 8,1%.(see graph 7)

GRAPH 7

CHAPTER FIVE

DISCUSSION

Compared to other studies, the consultation rate to psychiatry in this study was found to be exceedingly low 0,17%, as compared to rates between 0,9 - 4,2% (Diefenbacher,A., Strain,J.J., 2002:249; de Jonge, P., 2001:152; Kishi,Y., 2007: 517; Clark,D.M., Smith,G.C., 1995:424; Gangat,A.E., Naidoo, L.R., Simpson, M.A., 1987:853). The reason for this could be a low detection rate amongst the primary treating doctors, or it could be that the doctors find it difficult to consult psychiatry, due to the frequent changeover of liaison registrars from month to month. On the other hand, it could be that the doctors don’t feel the patient needs urgent intervention in the ward, and they could be booking them via the psychiatry outpatient clinic. Further investigation will have to be done to identify the exact reason for the low referral rate.

The patient sample was 74; 62% being female & 38% male. The mean age was 40 years. These findings were in keeping with those of another South African study were they found 57% to be female & 43% to be male (Nair, M.G., Pillay, S.S., 1997:144)

The reasons for referral were mainly that of aggression/behavioural problem, hallucinations, known psychiatric patient & confusion. This differs slightly from the results of other studies, where the authors found depression to be the commonest reason for referral to be depression (Diefenbacher,A., Strain,J.J., 2002:249; Kishi,Y., 2007: 517; Clark,D.M., Smith,G.C., 1995:424). The South African study done by Gangat, Naidoo and Simpson (1987: 853) had found depression to be the 2nd commonest reason for referral, behind parasuicide. In the aforementioned studies, patients were frequently seen for behavioural problems, and for evaluation of psychological/psychiatric problems, but there wasn’t mention of patients being referred due to being a “known” psychiatric patient. According to the researcher this shows some hesitancy on the part of the treating doctors to manage psychiatric patients on their own.

The pattern of the sources of referral was broadly in keeping with what was found in other studies in South Africa & internationally. Both Diefenbacher & Strain (2002: 249) in an American study, & Gangat, Naidoo and Simpson (1987: 853) in a South African study, found there to be majority of consults from internal medicine followed by surgery & obstetrics & gynaecology.

The other studies in the literature did not make mention of conditions that patients were being treated for by their referring doctors. In our study we found majority of patients had suffered from traumatic injury or fracture, HIV & TB, as well as epilepsy.

The most common diagnoses made were the organic brain syndromes i.e. delirium and dementia. This was in keeping with studies by Diefenbacher & Strain (2002: 249) as well as de Jong et al (2001: 152), but Gangat, Naidoo and Simpson (1987: 853) had found depression to be the most frequent diagnosis. Depression and the mood disorders in general feature quite prominently in most of the literature, yet in our study we found depression to make up only 5% of the diagnoses made. This raises the question of whether all patients with depression are being detected in the general wards of the hospital. It is another area that could be investigated further. According to a South African study, depression & substance problems were the commonest psychiatric conditions among general hospital patients (Nair, M.G., Pillay, S.S., 1997: 144)

Also of note was that psychosis due to a general medical condition was the 2nd most common diagnosis, a diagnosis which didn’t feature in any of the other studies. This could be due to the impact of HIV which is not as highly prevalent in the European countries as it is in this country. Even the study by Gangat, Naidoo and Simpson (1987: 853) makes no mention of it, and this could be due to the fact that this study was published in 1987, a time when HIV was just starting to be realised as a global pandemic. In our study, HIV accounted for 50% of the patients who were diagnosed as psychosis due to general medical condition, epilepsy accounted for 35%, and 15% were due to hypertension & carcinoma.

CHAPTER SIX

CONCLUSION

The referral rate to C-L psychiatric services in the hospital is low compared to other institutions both locally and abroad. More needs to be done to establish a proper C-L psychiatric service. Having a full time consultant allocated to C-L psychiatry and having a registrars rotation in C-L psychiatry extended to perhaps 3 months may make it easier for other departments to refer patients.

HIV has had an impact on the type of patients we encounter during liaison. As many as 16% of the patients seen during liaison were given an HIV related diagnosis (either psychosis or mood disorder due to HIV).

Only 5% of patients referred were diagnosed with depression as opposed to other studies which found rates between 15,1 – 54,7%. It is the researcher’s opinion that a large proportion of patients with depression may remain undetected by their treating doctor & hence it may be beneficial to educate our colleagues in other departments in the use of screening instruments, like the Beck’s Depression Inventory, so that they may be able to refer more cases to us. This is perhaps another area that could be further investigated. In the South African setting, there aren’t enough studies that document the prevalence of mental disorders in the general hospital, with the last study taking place 13 years ago (Nair, M.G., Pillay, S.S., 1997:144)

LIMITATIONS OF THE STUDY

This study was limited by the fact that, though registrars are supervised by consultants, due to staff constraints, there isn’t any one particular consultant allocated to C-L psychiatry & hence individuals may arrive at different diagnoses. Many of the patients that were referred may have been referred to psychiatry outpatient department as they may have been deemed not to need urgent intervention at that time hence they may have been missed by our study sample.

RECOMMENDATIONS

This study has highlighted the fact that more needs to be done to improve C-L psychiatric services in the hospital. Furthermore, we need more studies to be done to elucidate the exact reasons behind why we are having such a low referral rate. A study can also be undertaken to establish the exact prevalence of mental disorders among general hospital inpatients, so that we may correlate this with the referral rate in general, and, more especially, for conditions such as depression, which was also detected to be low in this study. This would be beneficial as current research on the prevalence of mental disorders amongst hospital inpatients is lacking in South Africa.

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