A LITHIUM REGISTER FOR ADULTS WITH INTELLECTUAL DISABILITIES - CAN IT WORK?

Transcription

1 The British Journal of Developmental Disabilities Vol. 53, Part 1, JANUARY 2007, No. 104, pp A LITHIUM REGISTER FOR ADULTS WITH INTELLECTUAL DISABILITIES - CAN IT WORK? Sabyasachi Bhaumik, Joanna M. Watson, James F. Falconer Smith, Sanyogita Nadkarni, Asit Biswas, Satheesh Kumar Gangadharan Introduction Lithium is used in adults for the prophylaxis and treatment of mania, bipolar disorder and recurrent depression (Burgess et al., 2001; Joint Formulary Committee, 2005) and additionally in adults with intellectual disabilities (ID) to control behaviour disorders, especially aggression and self-injurious behaviour (Craft and Mathews, 1984; Bhaumik and Branford, 2005). Adults with ID are as prone to side effects of lithium as those in the general adult population (Pary, 1991). The narrow therapeutic/toxic ratio of lithium makes regular clinical review and careful monitoring of serum lithium levels and renal and thyroid function essential (Joint Formulary Committee, 2005). *Dr Sabyasachi Bhaumik MB BS DPM FRCPsych Consultant in Learning Disability Psychiatry, Leicestershire Partnership NHS Trust, Leicester Frith Hospital, Groby Road, Leicester, LE3 9QF, UK Honorary Senior Lecturer, University of Leicester, UK bhaumikuk@yahoo.co.uk Tel: + 44 (0) Fax: + 44 (0) Dr Joanna M Watson MA MB BChir FFPH Associate Specialist in Learning Disability Psychiatry, Leicestershire Partnership NHS Trust, Leicester Frith Hospital, Groby Road, Leicester, LE3 9QF, UK Research Associate, University of Leicester, UK James F Falconer Smith DM FRCP FRCPath Consultant Chemical Pathologist, Glenfield Hospital, University Hospitals of Leicester NHS Trust, Groby Road, Leicester, LE3 9QP Sanyogita Nadkarni MB BS MRCPsych Former Staff Grade in Learning Disability Psychiatry, Leicestershire Partnership NHS Trust, Leicester Frith Hospital, Groby Road, Leicester, LE3 9QF, UK Asit Biswas MD MRCPsych DPM MMedSci Consultant in Learning Disability Psychiatry, Leicestershire Partnership NHS Trust, Leicester Frith Hospital, Groby Road, Leicester, LE3 9QF, UK Satheesh Kumar Gangadharan MRCPsych MD (Psych) Consultant in Learning Disability Psychiatry, Leicestershire Partnership NHS Trust, Leicester Frith Hospital, Groby Road, Leicester, LE3 9QF, UK * For Correspondence 37

2 Substandard lithium monitoring may be widespread in both hospital and general practice (Kehoe and Mander, 1992; Ryman, 1997; Moscovich, 1997; Eagles et al., 2000; Buckley and Sharrard, 2003; Glover and Lawley, 2005). Although many health districts have established lithium clinics for the general population, little is known about the use, tolerance and monitoring of lithium in adults with ID. Leicestershire Partnership NHS Trust provides multidisciplinary communitybased services and hospital facilities for mental health and learning disability (LD) within the unitary authorities of Leicester, Leicestershire and Rutland. It has a population of approximately one million people (Office of Population Censuses and Surveys, 2002). The Leicestershire LD Register has identified around 3,400 adults with ID aged 19 and over living within the trust area. A central laboratory-based lithium register was set up in 1999 for the general population in Leicestershire following an audit of lithium monitoring by general practitioners in two localities (Farooqi et al., 2002). Patients with ID were not included on the lithium register unless they were seen by general adult psychiatrists. In 2000, the LD psychiatrists in Leicestershire initiated a cross-sectional audit to review the use and monitoring of lithium in adults with ID within the trust. obtaining lists of eligible patients from the consultant LD psychiatrists and inpatient pharmacy. Two standards were set by consensus of the multidisciplinary LD team based on British National Formulary recommendations, with a change from quarterly to six-monthly lithium checks. All adults with ID on long-term lithium should have: six-monthly serum lithium checks annual blood tests for renal (urea and electrolytes) and thyroid function. Thus the audit reviewed the necessity for quarterly lithium checks in the local ID population given the frequent problems with taking blood, communication difficulties and the wide geographical area without a centralised lithium clinic. Data were collected from the medical notes about each patient s age; sex; residence; primary cause and severity of ID; epileptic status; current medication; indication for lithium; current dose and any side effects of lithium; and the frequency of checking serum lithium levels, renal function and thyroid function in the past year. The results were tabulated and compared with the audit standards. The baseline audit report recommended that a lithium register should be set up for adults with ID and a re-audit done after a year. Method Baseline audit All adults with ID on long-term lithium treatment who were accessing LD services were included. They were identified by examining the case notes of all active outpatients and inpatients; and by Lithium register In 2002, the LD Service and Chemical Pathology Department, funded by Leicestershire Health Authority, established a lithium register for adults with ID. The register maintains a list of patients on long-term lithium in hospital and community settings. It provides an automated system of scheduling, reporting 38

3 on and following up blood tests to assist doctors monitoring lithium in registered patients. Each patient has a personalised target range of serum lithium specified by the referring doctor. A consultant chemical pathologist is responsible for running the register and a consultant LD psychiatrist is the lead clinician for lithium monitoring. Standard lithium treatment cards and information sheets for patients and carers are used when the referring doctor indicates that it is appropriate. Re-audit The aim of the cross-sectional re-audit carried out in 2003/2004 was to assess the effectiveness of the register in improving lithium monitoring. The objectives were to ascertain the completeness of coverage of the register; to determine the proportion of patients on lithium having the necessary monitoring tests; and to compare these results with the standards set for lithium monitoring. The methodology was similar to that of the baseline audit. The lithium register provided an additional source of identification of eligible patients. The completeness of the register was checked by comparing the list of registered patients with the names of patients from all LD services having lithium checks. Any abnormal blood test results were noted. Where patients on lithium at baseline were no longer taking lithium, the reasons for this were ascertained from their medical notes. The results were tabulated, compared with the baseline findings and assessed against the standards. The following standards were set by consensus of the local multidisciplinary Guidelines Development Group (Box I). Box I Standards for the re-audit All adults with ID on long-term lithium: 1) should be on the ID lithium register 2) should have six-monthly serum lithium checks 3) should have annual blood tests for renal function (urea and electrolytes) 4) should have annual blood tests for thyroid function The results of the re-audit were reported to the group and further recommendations made. Results The baseline audit identified 63 patients on long-term lithium and the re-audit 49 patients. 14 patients taking lithium at baseline had been changed to a different mood stabiliser (sodium valproate or lamotrigine) by the time of the re-audit because lithium had not been sufficiently efficacious and/or carrying out regular blood tests was proving to be difficult. Patient characteristics 36 men (57%) and 27 women (43%) were included in the baseline audit and 23 men (47%) and 26 women (53%) in the re-audit (TABLE I). There were similar age distributions at the two audit points, with around three quarters of patients being aged Withdrawal of proportionally more men than women from lithium resulted in reversal of the male:female ratio. The majority of patients lived in the community, with 30% and 18% living in NHS hospitals or group homes at baseline and re-audit respectively. 39

4 At baseline, 41 patients (65%) had no known primary cause of ID and 14 (22%) had active epilepsy. At re-audit, no primary cause of ID was identified in 32 patients (65%). Ten patients had diagnoses of autistic spectrum disorder, two Down syndrome, one Fragile X syndrome, one Klein-Levine syndrome, one Klinefelter syndrome and one with ID secondary to a road traffic accident in childhood. Seven patients (14%) had active epilepsy. At both audit points, lithium was most frequently used in individuals with mild ID and not at all in those with profound ID (TABLE II). Using data from the Leicestershire LD Register to estimate the prevalence of lithium therapy within the local ID population at re-audit, 3.3% of adults with mild ID were taking lithium, 3.2% of those with moderate ID and 1.4% of those with severe ID. Use of lithium The commonest indication for using lithium was bipolar affective disorder (TABLE III). The number and proportion of patients receiving lithium for behaviour problems - mainly aggression and selfinjurious behaviour - fell between the baseline audit and re-audit from 24 patients (38%) to nine (18%). Seven of these nine patients showed cyclical behaviour disturbance. TABLE I Age and sex distribution of individuals in the baseline audit and re-audit Baseline audit (2002) Re-audit (2003/4) Age Group Males Females Persons (%) in each age group Males Females Persons (%) in each age group (13%) (14%) (30%) (24%) (29%) (27%) (21%) (24%) (8%) (10%) All ages 36 (57%) 27 (43%) 63 (101%) a 23 (47%) 26 (53%) 49 (99%) a a - rounding error TABLE II Level of intellectual disability in individuals treated with lithium Number (%) of individuals Level of intellectual disability Baseline audit (2002) Re-audit (2003/4) Mild (IQ a 50-69) 24 (38%) 21 (43%) Moderate (IQ 35-49) 21 (33%) 18 (37%) Severe (IQ 20-34) 19 (30%) 10 (20%) Profound (IQ <20) All levels 63 (101%) b 49 (100%) a - IQ = intelligence quotient b - rounding error 40

5 Abnormal blood test results At re-audit, serum lithium levels were within the therapeutic range in 45 patients (92%). They were elevated in three patients (6%) and reduced in one (2%). Appropriate measures were taken in all four cases. Abnormal urea and electrolyte results were reported in ten patients (20%) and abnormal thyroid function tests in six (12%). 60% of patients had no abnormal results. Side effects and polypharmacy 16% of patients at baseline and 4% at re-audit suffered from presumed side effects of lithium. At baseline, four patients had gained weight, three had developed hypothyroidism (two of whom were prescribed thyroxine) and three had neurological side effects (tremor and ataxia). At re-audit, one patient was obese, one had hypothyroidism and one had neurological side effects. However, there was no clear relationship between side effects and high serum lithium (which was generally within the therapeutic range for the individual when rechecked a few weeks later). Polypharmacy was high in both hospital and community settings. At baseline, 56 patients (89%) were taking at least one other drug as well as lithium. At re-audit, all the patients except one (98%) were prescribed at least one other drug; and 34 patients (69%) two or more. The most frequently co-prescribed drugs were antipsychotics (42 patients), antidepressants (18 patients), other mood stabilisers (eight patients) and anti-epileptics (eight patients). 17 patients in the re-audit were maintained on an antipsychotic, an antidepressant and lithium. Comparison with the audit standards At baseline, only 21 patients (33%) had had serum lithium checks in the previous six months. 37 patients (59%) had had renal and thyroid function tests in the past year. At re-audit, seven patients were identified as being on long-term lithium but were not included on the register. All 42 patients on the register had had sixmonthly serum lithium checks (Box II). Among the patients not on the register, one had had serum lithium checked seven months previously, two eight months TABLE III Indications for the use of lithium in the baseline audit and re-audit Number (%) of individuals Main indication for the use of lithium Baseline audit (2002) Re-audit (2003/4) Bipolar affective disorder 30 (48%) 28 (57%) Behaviour problems/aggression 24 (38%) 9 (18%) Schizoaffective disorder 6 (10%) 6 (12%) Rapid cycling mood disorder 2 (3%) 4 (8%) Recurrent depression (4%) Other affective disorders 1 (2%) - - Total 63 (101%) a 49 (99%) a a - rounding error 41

6 previously and four not for over a year. All the registered patients had had both annual renal and annual thyroid checks. Box II Achievement of the standards in the re-audit Of the 49 adults with ID on long-term lithium: 1) 42 (86%) were on the ID lithium register 2) 42 (86%) had had six-monthly serum lithium checks 3) 46 (94%) had had annual blood tests for renal function (urea and electrolytes) 4) 45 (92%) had had annual blood tests for thyroid function Practical Application and Discussion The lithium register We believe that our register is the first lithium register in the UK specifically for adults with ID. It is used in essentially the same way as the main lithium register but kept administratively separate for operational simplicity and ease of audit. The re-audit found 86% completeness of coverage of the ID lithium register. The seven patients on lithium who had been missed were hospital inpatients being monitored by ward staff. The omission of these patients from the register had been due to an administrative oversight. All seven patients were subsequently added to the register. Use of lithium Lithium was used most often for treating bipolar affective disorder and behaviour problems. Other patients received lithium for schizoaffective disorder, rapid cycling mood disorder and recurrent depression. These are all common indications for the long-term use of lithium for which there is evidence of effectiveness (Craft and Mathews, 1984; Clarke and Pickles, 1994; Joint Formulary Committee, 2005; Bhaumik and Branford, 2005). The decrease in the number and proportion of patients prescribed lithium for behaviour problems may reflect the increasing range of treatment options, including the use of newer antipsychotics, which do not require monitoring by regular blood tests. Lithium was used most frequently in those with mild/moderate ID, where diagnosable mental health problems are more common than in those with severe/ profound ID (Bhaumik and Branford, 2005). Bipolar affective disorder occurs in individuals with all levels of ID, often with a pattern of rapid cycling (Craft and Mathews, 1984; Berney and Jones, 1988; Vanstraelen and Tyrer, 1999). However, the diagnosis of bipolar affective disorder and depression may be more difficult in those with severe/profound ID due to communication problems and the presence of associated sensory and motor disabilities. Long-term use of lithium is associated with mild cognitive and memory impairment (Joint Formulary Committee, 2005). This may be particularly difficult to monitor in the ID population because of various underlying cognitive deficits. Long-term lithium is only prescribed after careful assessment of all the risks and benefits. 42

7 Abnormal blood test results At re-audit, the proportions of patients with ID with serum lithium levels within the therapeutic range (92%), with elevated serum lithium (6%) and with reduced serum lithium (2%) were not significantly different from the corresponding proportions for patients on the Leicestershire lithium register for the general population (89%, 8% and 3% respectively). Similarly, there were no significant differences between the proportions of patients on the ID lithium register and those on the general lithium register with abnormal renal function tests (20% and 24% respectively) or abnormal thyroid function tests (12% and 9% respectively). Polypharmacy This audit and earlier studies have shown that polypharmacy is high in the ID population. This makes it comparatively difficult to identify the beneficial effect of lithium in this situation. Polypharmacy, vulnerability and lack of capacity limit the participation of many patients with ID in randomised controlled trials. Lithium monitoring Six-monthly serum lithium checks were made in 86% of patients in our re-audit compared with 76% in Ryman s audit in the general population (Ryman, 1997). Most audits in the general population aim for quarterly serum lithium checks but achievement varies widely: 33% (Ryman, 1997), 52% (Glover and Lawley, 2005), 54% (Eagles et al., 2000), 61% (Farooqi et al., 2002), 93% (Taylor and Dewar, 1994) and 95% (Kehoe and Mander, 1992). In our re-audit, only 6% of patients had elevated serum lithium levels compared with 26% in Ryman s study, two thirds of whom were not followed up. The local consensus is that six-monthly lithium checks are realistic, cost-effective and consistent with best practice in the ID population. At re-audit, 94% of patients had had annual renal function tests. This was superior to the results of published audits, which ranged from 42% (Farooqi et al., 2002) to 79% (Ryman, 1997). 92% of our patients had had annual thyroid function tests compared with 45% (Moscovich, 1997) to 77% (Ryman, 1997) elsewhere. Safe, effective treatment with lithium needs careful systematic monitoring by clinical review; blood checks with appropriate follow-up; and clear communication between general practitioners, psychiatrists, patients and carers (Ryman, 1997; Farooqi et al., 2002; Buckley and Sharrard, 2003). In another study of lithium monitoring in patients with ID, the responsible doctor was identified in only 59% of cases before and 87.5% after introducing guidelines (Buckley and Sharrard, 2003). Our register ensures that the doctor responsible for lithium monitoring is known in every case and that all the relevant professionals involved are sent copies of all the results. Eliciting the views, knowledge and compliance of patients and carers was outside the remit of our audit. A study of adults with ID taking lithium and their carers showed that those with a greater knowledge of lithium tended to have a more positive attitude to their treatment, which may be important in increasing compliance and preventing lithium toxicity (Clarke and Pickles, 1994). The lithium information sheets and treatment cards used by the register were written for the general population. Lithium treatment cards and information sheets were sent to 27 patients on the register (55%) and their 43

8 carers. The safe treatment and monitoring of lithium might be further improved by giving these to all the carers and preparing an accessible lithium treatment leaflet and card and other accessible materials for patients. Our re-audit established the clear benefits of the lithium register in improving the standards of lithium monitoring in adults with ID. The improvements were greater than for the Leicestershire lithium register for the general population (Farooqi et al., 2002). The audit standards were set high because of the narrow therapeutic/ toxic ratio of lithium and the risk of serious consequences if careful monitoring is not carried out. Although none of the re-audit standards was attained, there was significant improvement in lithium monitoring compared with the baseline results. Standards 2 to 4 were achieved for all 42 patients (100%) who were on the lithium register. Recommendations 1) The ID lithium register should be maintained as an effective way of monitoring patients with ID on longterm lithium. 2) Serum lithium checks should be carried out six-monthly in these patients. 3) A software programme should be developed within the outpatient administration system to add patients newly prescribed lithium to the register automatically. 4) A systematic check on the completeness of the register should be made annually. 5) Accessible lithium treatment materials should be prepared for adults with ID. Summary The aim of this cross-sectional audit was to review the use, tolerance and monitoring of lithium in adults with intellectual disabilities (ID) in Leicestershire, UK. A baseline audit identified all the adults with ID maintained on lithium and reviewed the indications for lithium treatment, any side effects and the frequency of monitoring serum lithium and renal and thyroid function. After a lithium register for adults with ID was set up, a re-audit assessed its effectiveness in improving lithium monitoring. Lithium was used for mood and behaviour disorders, most frequently in individuals with mild ID. Generally, lithium was well tolerated. At baseline, 21 (33%) of 63 adults had six-monthly serum lithium checks. At re-audit, 42 (86%) of 49 adults were on the lithium register. The same 42 (86%) patients had six-monthly lithium checks. Annual renal function tests increased from 59% at baseline to 94% at re-audit; and annual thyroid function tests from 59% to 92%. The audit standards were met for all the patients on the lithium register. The audit demonstrated that a lithium register for adults with ID facilitates lithium monitoring and that six-monthly lithium checks are appropriate in this population. Accessible information about lithium treatment should be prepared for adults with ID. Acknowledgements The authors wish to thank Elena Wragg and Pat Gibbs from the Clinical Audit Department and Dr Sisir Majumdar, Consultant Psychiatrist, for their assistance with data collection during the re-audit; Kathryn Marsden, Co-ordinator of the 44

9 Lithium Register, for supplying additional information from the register; and John Devapriam, Specialist Registrar in Learning Disability Psychiatry, and Jane Tatlow, Deputy Librarian at the Glenfield Hospital, for their help with the literature review. References Berney T.P. and Jones P.M. (1988). Manic depressive disorder in mental handicap. Australia and New Zealand Journal of Developmental Disabilities, 14, 3-4. Bhaumik S. and Branford D. (Eds) (2005). The Frith Prescribing Guidelines for Adults with Learning Disability. London: Taylor & Francis. Buckley C. and Sharrard H. (2003). Lithium monitoring for patients with learning disability: the role of the general practitioner. Quality in Primary Care, 11, Burgess S., Geddes J., Hawton K., Townsend E., Jamison K. and Goodwin G. (2001). Lithium for maintenance treatment of mood disorders. The Cochrane Database of Systematic Reviews, issue 3, article CD DOI: / CD Clarke D.J. and Pickles K.J. (1994). Lithium treatment for people with learning disability: patients and carers knowledge of hazards and attitudes to treatment. Journal of Intellectual Disability Research, 38, Craft M. and Mathews J. (1984). Lithium in mental handicap: a review. Mental Handicap, 12, Eagles J.M., McMann I., Macleod T.N.N. and Paterson N. (2000). Lithium monitoring before and after the distribution of clinical practice guidelines. Acta Psychiatrica Scandinavica, 101, Farooqi A., Falconer Smith J., Lakhani M., Meakin C., Sorrie R. and Ashmore S. (2002). The impact and acceptability of a central register on monitoring of lithium therapy: professional and patient perspectives. Journal of Clinical Governance, 10, 3, Glover K.J. and Lawley D. (2005). How safe is lithium prescribing? Audit of a local prescribing framework and patient survey. Psychiatric Bulletin, 29, Joint Formulary Committee (2005). British National Formulary 51 March British Medical Association and Royal Pharmacological Society of Great Britain, pp Kehoe R.F. and Mander A.J. (1992). Lithium treatment: prescribing and monitoring habits in hospital and general practice. BMJ, 304, Moscovich D.G. (1997). Lithium follow-up in general practice. International Journal of Clinical Practice, 51, Office of Population Censuses and Surveys (2002) Census. Outline Statistics for England and Wales Derived from County Monitors. London: HMSO. Pary R. (1991). Side effects during lithium treatment for psychiatric disorders in adults with mental retardation. American Journal of Mental Retardation, 96, Ryman A. (1997). Lithium monitoring in hospital and general practice Psychiatric Bulletin, 21, Taylor R. and Dewar I.G. (1994). Lithium audit in the Scottish borders. Psychiatric Bulletin, 18, Vanstraelen M. and Tyrer S.P. (1999). Rapid cycling bipolar affective disorder in people with intellectual disability: a systematic review. Journal of Intellectual Disability Research, 43,