Patterns of prescribing

In accord with published research, ^{Reference Alanen, Finne–Soveri, Noro and Leinonen12} analysis of our audit data revealed that age, care setting and type and severity of dementia were all independently linked to the prevalence of antipsychotic drug prescribing in dementia. The highest prevalence of antipsychotic prescribing was found on psychiatric wards and in private continuing care. The relatively high prevalence in care homes for the elderly mentally infirm (EMI), ranging from 26% in EMI residential homes to 44% in EMI nursing homes, is consistent with previously reported estimates of 20–50% in the UK. ^{Reference Testad, Auer, Mittelman, Ballard, Fossey and Donabauer3,Reference McGrath and Jackson13,Reference Alldred, Petty, Bowie, Zermansky and Raynor14} As a predictor variable, care home setting may be partly a proxy for clinical variables not collected in our audit, such as level of dependency and the severity and complexity of behavioural problems such as agitation or aggression. The latter has been previously observed to be associated with a higher likelihood of antipsychotic use. ^{Reference Monette, Alessa, McCusker, Cole, Voyer and Champoux15} A US study attributed variation in antipsychotic use to a nursing-home level ‘prescribing culture’ that exists in some institutions, ^{Reference Chen, Briesacher, Field, Tjia, Lau and Gurwitz16} whereas a Canadian study found that physical setting characteristics, specifically absence of a clock or calendar and telephone, may be relevant. ^{Reference Monette, Alessa, McCusker, Cole, Voyer and Champoux15} Further studies are needed to understand these associations more fully.

TABLE 2 Documented clinical indications and target symptoms for antipsychotic medication in the BPSD group (n = 1620)

IndicationFootnote a	BPSD groupFootnote b n (%)
Agitation	821 (51)
Evident or assumed psychotic symptoms	736 (45)
Physical aggression	683 (42)
Verbal aggression	680 (42)
Distress	425 (26)
Resisting help with activities of daily living	320 (20)
Disturbed sleep	239 (15)
Wandering	236 (15)
Fear/anxiety	194 (12)
Disinhibited behaviour	156 (10)
Depression/low mood	130 (8)
Unclear/other	126 (8)

BPSD, behavioural and psychological symptoms of dementia.

^a. Indications are not mutually exclusive; i.e. for an individual patient an antipsychotic drug might be prescribed for more than one indication, or more than one drug might be prescribed to target the same indication.

^b. The BPSD group is the subgroup of patients with dementia but no comorbid psychotic illness who are receiving antipsychotic medication.

Antipsychotics were more often prescribed for non-Alzheimer's disease dementia, despite even poorer evidence for efficacy and a potentially greater risk of harm. The highest prevalence of antipsychotic prescribing was in the small subgroup of patients with dementia associated with Parkinson's disease. This is in line with the findings of a large US database study, which found a significantly higher use of antipsychotic medication in patients with both Parkinson's disease and dementia compared with those with other subtypes of dementia. ^{Reference Weintraub, Chen, Ignacio, Mamikonyan and Kales17} In our sample 30% of the 228 people with Parkinson's disease dementia were prescribed an antipsychotic. Possible explanations are that psychosis may be more common in this subgroup, perhaps partly due to treatment with dopaminergic drugs. It is likely that this complexity would have led to an appropriate, selective referral of such patients to psychiatric services.

TABLE 3 Prescription of psychotropic medication (other than antipsychotic drugs) to patients with dementia but no comorbid psychotic illness

	Patients regularly prescribed this medicine, n (%)
	Patients with dementia but no psychotic illness (n = 9825)	Subgroup prescribed an antipsychoticFootnote a (n = 1620)	Subgroup not prescribed an antipsychotic (n = 8205)	Antipsychotic subgroup v. no antipsychotic subgroup χ2, P
Analgesic	1184 (12)	238 (15)	946 (12)	12.71, P = 0.001
Anticholinergic	108 (1)	44 (3)	64 (<1)	46.644, P<0.001
Antidepressant
SSRI	1679 (17)	353 (22)	1326 (16)	30.257, P<0.001
Trazodone	473 (5)	131 (8)	342 (4)	45.325, P<0.001
Other	1062 (11)	272 (17)	790 (10)	71.978, P<0.001
Carbamazepine	140 (1)	49 (3)	91 (1)	35.344, P<0.001
Cholinesterase inhibitor	4213 (43)	441 (27)	3772 (46)	194.181, P<0.001
Benzodiazepine
Lorazepam	312 (3)	133 (8)	179 (2)	159.897, P<0.001
Other	492 (5)	166 (10)	326 (4)	111.941, P<0.001
Memantine	419 (4)	113 (7)	306 (4)	34.912, P<0.001
Valproate	228 (2)	88 (5)	140 (2)	82.851, P<0.001
Z-hypnotic	473 (5)	196 (12)	277 (3)	224.631, P<0.001

SSRI, selective serotonin reuptake inhibitor.

^a. The BPSD group is the subgroup of patients with dementia but no comorbid psychotic illness who are receiving antipsychotic medication.

The observed patterns of antipsychotic usage were consistent with previous studies, with doses tending to be at the lower end of the licensed range. There was high usage of quetiapine, accounting for over a third (36%) of all antipsychotic prescriptions, despite a lack of positive efficacy data in dementia. ^{Reference Tariot, Schneider, Katz, Mintzer, Street and Copenhaver18,Reference Sultzer, Davis, Tariot, Dagerman, Lebowitz and Lyketsos19} The next most commonly prescribed antipsychotic was risperidone (26%), the only antipsychotic currently licensed (on a restrictive set of indications) for the short-term management of BPSD. There was low usage of olanzapine and rare usage of clozapine. The common use of quetiapine might be partly explained by its perceived favourable tolerability profile, particularly in relation to extrapyramidal side-effects, and that it was not specifically implicated in the early Medicines and Healthcare Products Regulatory Agency warning of the risk of stroke with antipsychotic drugs in dementia. ⁸ The only first-generation antipsychotic commonly used was haloperidol, and this was usually prescribed on an ‘as required’ (p.r.n.) basis.

Quality of antipsychotic prescribing

Our audit data suggest that the prescribing of antipsychotic drugs by specialist old age psychiatric services in the UK for people with dementia in 2010–2011 is largely compliant with treatment recommendations, in that alternative interventions had been considered in the majority of cases before medication was prescribed, and when it was prescribed there was clear documentation of the target symptoms. The most common clinical indications were agitation, evident or assumed psychotic symptoms, aggression and distress. This observed adherence to standards in the UK may reflect the desired effect of NICE guidelines. It is also consistent with the American experience of the impact of the US Food and Drug Administration advisory on second-generation antipsychotic use among all individuals and those 65 years or older with dementia. ^{Reference Dorsey, Rabbani, Gallagher, Conti and Alexander20} However, our audit also revealed aspects of antipsychotic prescribing practice that were suboptimal – in particular, the low level of review in cases prescribed such drugs long-term. In the subsample of patients prescribed an antipsychotic drug, almost two-thirds had been receiving it for at least 6 months, which is consistent with findings reported by Ballard et al. ^{Reference Ballard, Hanney, Theodoulou, Douglas, McShane and Kossakowski21} We found that only three-quarters of these patients had had a documented medication review in the previous 6 months. This group might be particularly vulnerable to suboptimal monitoring for several reasons. Although antipsychotic treatment for dementia is most commonly initiated in secondary care, prescribing responsibility is commonly transferred to primary care subsequently, with the risk of undefined responsibility for continued medication review. This may be further compounded by poor communication between general practitioners and psychiatrists. ^{Reference Soyinka and Lawley22} It has also been observed that primary care can be less successful than specialist mental health teams at withdrawing antipsychotics. ^{Reference Malone, Bradley and Lindesay23}

TABLE 4 Multivariable analysis of effect of potential explanatory variables on being prescribed an antipsychotic drug in patients with dementia but no comorbid psychotic illness (n = 9825)

	Odds ratio (95% CI)	P
Age group, years
⩽70	1
71–80	0.95 (0.76–1.18)
81–90	0.71 (0.57–0.88)
91+	0.58 (0.43–0.77)	<0.001
Care setting
Own home	1
Residential home	2.40 (1.93–2.97)
EMI residential home	2.65 (2.06–3.39)
Nursing home	3.26 (2.44–4.35)
EMI nursing home	4.81 (3.82–6.05)
Psychiatric ward	6.93 (5.71–8.43)
NHS continuing care	2.14 (1.50–3.07)
Private continuing care	3.90 (1.71–8.86)
Medical/surgical ward	2.93 (1.51–5.68)	<0.001
Type of dementia
Alzheimer's disease	1
Alzheimer's disease/mixed	0.84 (0.71–1.01)
Vascular	1.60 (1.35–1.89)
Parkinson's disease	2.34 (1.64–3.34)
Other	1.71 (1.26–2.31)
Unspecified	1.14 (0.86–1.50)	<0.001
Severity of dementia
Mild	1
Moderate	1.90 (1.56–2.32)
Severe	3.27 (2.62–4.08)	<0.001

EMI, elderly mentally infirm; NHS, National Health Service.

Other drugs prescribed

The patients in this sample received a range of other medications. These included analgesics, antidepressants, valproate, benzodiazepines and z-hypnotics; all were prescribed more often for the subgroup of patients who were prescribed an antipsychotic. It is possible that these drugs were also being used to target BPSD. Indeed, there is some evidence that pain is associated with behavioural disturbances and depression in people with dementia, and that analgesics may be as effective as antipsychotics in reducing agitation in such cases. ^{Reference Husebo, Ballard, Sandvik, Nilsen and Aarsland24} There is also limited evidence to suggest that antidepressants may have a modest effect in reducing agitation, although not depression, in people with dementia. ^{Reference Seitz, Adunuri, Gill, Gruneir, Herrmann and Rochon25,Reference Banerjee, Hellier, Dewey, Romeo, Ballard and Baldwin26} In contrast, there is no evidence supporting the efficacy of valproate but some indicating potential harm. ^{Reference Lonergan and Luxenberg27} Benzodiazepines have been tentatively recommended for the management of mild agitation, although there is no study of people with dementia. These drugs, alongside the z-hypnotics, are likely to be seen as more directly targeting agitation and insomnia, and as being safer in some ways than antipsychotics; but both groups of drugs are associated with an increased risk of falls.

Cholinesterase inhibitors, conversely, were less likely to be prescribed in the subsample of patients prescribed an antipsychotic. This may be due to the inverse relationship that exists between cognition and BPSD; cholinesterase inhibitors are indicated for mild to moderate dementia, whereas BPSD are more prevalent in moderate to severe dementia. Most antipsychotics also have anticholinergic activity, which is associated with hazards for older people such as urinary retention, blurred vision and impaired cognition. ^{Reference Fox, Richardson, Maidment, Savva, Matthews and Smithard28} Further, this activity would be likely to negate the effects of the cholinesterase inhibitors in the 25% of patients prescribed both an antipsychotic and a cholinesterase inhibitor. Such co-prescribing has been seen in other large samples of people with dementia, ^{Reference Langballe, Engdahl, Seabaek and Nordeng29} although the efficacy and tolerability of such regimens have not been formally tested in randomised controlled trials.

Limitations and strengths of the study

The audit data were collected by local staff, so there may have been error and variability in the data abstraction process. Also, the local clinical services were responsible for selecting which clinical teams would participate, and the numbers and types of services involved varied by respondent. Although these factors might act to limit the generalisability of the data, this effect is probably minimal given the large sample size and the involvement of the large majority of English mental health NHS trusts. Thus, the findings may be seen as representative of current clinical practice in specialist mental health services, although they cannot be readily extrapolated to primary care.

Implications for quality improvement

The main aim of this audit was to provide performance data (benchmarked against clinical practice standards) to participating services, stimulating reflective practice, as part of a QIP. Further, our findings identify two priorities for quality initiatives in this area: first, the high prevalence of antipsychotic prescribing on psychiatric wards and in care homes, and second, the frequency and thoroughness of the review of medication for patients prescribed antipsychotics beyond the short term. Individual trusts participating in this audit have started to publish and use their data to benchmark and identify priorities for improvement. Other local audits are reported to have led to improvements, including a modest reduction in the prescribing of antipsychotic drugs in nursing homes following the introduction of a checklist and 6-monthly reviews. ^{Reference Morrison30} Audit now appears embedded in secondary care as a quality improvement mechanism. However, other techniques have been reported to improve prescribing practice in vulnerable groups of patients. These include clearer communication of information around prescribing and follow-up; formal integration of a clinical pharmacist into community healthcare systems; and incentivised practice such as the Quality and Outcomes Framework. ^{Reference Schembri Wismayer and Sipos31,Reference Stuijt, Franssen, Egberts and Hudson32}

Implications for future practice

The findings we report here are important for two main reasons. First, they indicate that mental health teams dealing with patients with dementia and a high level of BPSD are able to manage all but 16% without recourse to antipsychotics. However, this is an overall prevalence figure for mental health services, and our data show that the proportion of patients prescribed antipsychotics varies markedly, depending on clinical setting and on particular demographic and clinical variables, such as being on a psychiatric ward, living in a care home, or having more severe dementia or dementia related to Parkinson's disease. Initiatives to change practice should take account of these factors, at the same time acknowledging that the optimal use of antipsychotic medication in such clinical subgroups remains unknown. Second, the benchmarked data generated from the audit allow the clinical services that participated to reflect on their own practice in relation to antipsychotic prescribing in patients with a diagnosis of dementia. The data indicate areas of relatively good practice, such as consideration of alternative interventions, and clear documentation of target symptoms when the medication is initiated. They also reveal areas for improvement, such as the frequency and quality of the review of long-term prescription of antipsychotic medication. Any impact on prescribing practice will be assessed in the QIP re-audit and in potential supplementary audits in the next few years.