Medication Side Effects

Empowerment in safeguarding involves risk management that is based on

understanding the person, understanding the autonomy of the person and how they or their carer view the risks they face (Sussex Multi Agency, 2011). However it may not be possible or even desirable to eliminate all risk with respect to medication use in the population with intellectual disabilities and behaviour disorders.

The identification of side effects to psychotropic and other medications causes difficulties in the population with intellectual disabilities. The international consensus process on psychopharmacology and intellectual disability in 1997 identified that this may be because:

• the patient’s functional handicap may be confused with certain symptoms, • many people with intellectual disability are unable to report the presence of

subjective side effects,

• some features frequently seen in the population with intellectual disability may

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• the population with intellectual disability may be at greater risk of side effects to

medications occurring (Reiss and Amam, 1997). [QI 3, QI 7, QI 9, QI 12, QI 15, QI 19, QI 21]

The results of an observational study comparing 138 antipsychotic-treated and 64 antipsychotic-naive participants with intellectual disability in one National Health Service Trust with general population controls suggested that antipsychotics at the low doses routinely prescribed for people with intellectual disability are

‘generally safe in relation to metabolic adverse effects, even if efficacy remains poorly defined’(Frighi et al., 2011b).

A UK study, published in 2011, was designed to identify the range of indications for which antipsychotic drugs are prescribed in people with intellectual disability and to audit clinical practice against three recognised standards. The three standards were:

1) The indication for treatment with antipsychotic medication should be documented in the clinical records.

2) The continuing need for antipsychotic medication should be reviewed at least once a year.

3) Side effects of antipsychotic medication should be reviewed at least once a year, and this review should include assessment for the presence of extra- pyramidal side effects, and screening for the four aspects of the metabolic syndrome: blood pressure, obesity, glycaemic control and plasma lipid profile. Following the audit of data for 2,319 patients the authors concluded that

‘In clinical practice, most prescriptions for antipsychotic drugs in people with intellectual disability are consistent with the evidence base and the overall quality of prescribing practice, as measured against recognised standards, is good, although in some patients potentially remedial side effects may not be detected and treated’ (Paton et al., 2011).

The standard in relation to side effects described in this study, was only applied to the subsample of patients who had been prescribed antipsychotic medication for a year or more and the results for this standard are presented here in Table 2.7.

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Table 2.7 Performance Against Standard for Monitoring of Side Effects Performance Against Standard for Monitoring of Side Effects • General statement in the clinical

records that side effects were either present or not present

1378 (69%)

• Patients treated for at least a

year

• No documented evidence of any EPS

assessment in 1165 (59%).

• No assessment of

a. weight/body mass index in 883 (44%)

b. blood pressure 1257 (63%) c. blood glucose 791 (40%) d. lipid profile 848 (43%)

• No documented evidence of

assessment of any of these specific side effects was found, nor any general statement about the presence or absence of side effects

247 (12%)

• Statement that side effects were

present/not present had been recorded in the case notes

• 72% of those with borderline/mild

intellectual disability

• 66% of those classified as

severe/profound intellectual disability The data presented in this audit did not suggest that patients with more severe

intellectual disability were more likely to be targeted for side effect review (Paton et al., 2011). A previous audit revealed that less than 15% of adults with intellectual disability prescribed second generation antipsychotic medications had all the parameters of metabolic syndrome monitored on a regular basis (Devapriam et al., 2009).

Frighi and colleagues, Box 2.3, found that 138 (68%) were on antipsychotics and 64 (32%) were antipsychotic naïve (Frighi et al., 2011b). 80 participants (58%) in the antipsychotic-treated group had challenging behaviour, which was the commonest reason for the prescription. There were more men (59%) in the antipsychotic-treated and more women (61%) in the antipsychotic-naive group. In the whole study group,

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27% of the participants had a diagnosis of challenging behaviour only, in the absence of psychiatric disorders.

Psychotropic Medication Use (n = 202)

97% were on one or more psychotropic agents, with a mean of 2.0 drugs per participant. (Mean = 1.4 per participant excluding anti-epileptics)

In total 68% were on antipsychotics, 42% on antidepressants, 39% on anti-epileptics, 25% on benzodiazepines (generally ‘as required’ rather than regularly), 2% on non- benzodiazepine hypnotics and 1% on lithium.

Of the 138 antipsychotic-treated participants, 48% were on risperidone, 18% on olanzapine, 10% on thioxanthenes, 9% on chlorpromazine or other first-generation phenothiazines, 9% on quetiapine, 7% on amisulpride or 4% on sulpiride.

Box 2.3 Psychotropic Medication Use

Comparisons with the general population showed that glucose and lipid parameters were on average the same or even more favourable in the intellectual disability group. In women with intellectual disability, prevalence of overweight/obesity and of Type 2 diabetes were markedly higher in the intellectual disability group. The relatively small number of people in the study taking olanzapine and clozapine, which are

antipsychotics with the highest potential metabolic impact, and the low doses

prescribed could account for the absence of any effect in relation to glucose and lipid parameters. In their summary, the authors identified that the findings of the Oxford Learning Disabilities Study provides an initial evidence base underpinning the safe use of antipsychotic drugs in the intellectual disability population (Frighi et al., 2011a). The study identified hyperprolactinaemia as the commonest side-effect in people with intellectual disability administered antipsychotic medications and hyperprolactinaemic hypogonadism as a complication of risperidone and amisulpride treatment, leading to

bone loss in a population already at risk for osteoporosis and fractures. Frighi et al., noted that antipsychotics continue to be consistently used for challenging

behaviour and advise that this practice would be difficult to defend in such a population group if it led to major metabolic side-effects. However their findings offered significant reassurance in relation to cardiovascular and metabolic risk in the population with intellectual disability. They did however caution that there may be potential problems in a susceptible subgroup and that regular monitoring of blood glucose, lipids and weight

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should be instituted when prescribing antipsychotics to people who may already have risk factors for diabetes, and when using antipsychotics with a high metabolic impact (Frighi et al., 2011a).

The results of a longitudinal study with random sampling and selection which commenced in Melbourne, Australia in 1994, were suggestive that advice on

medications may be forgotten over time by an older cohort, so that the importance of regular monitoring and reinforcement by doctor and pharmacist is needed (Thomson et al., 2010). The important role of doctors and pharmacists as educators was

emphasized by another study that found starting a new medication, cessation of a medication or changes to prescribed and over the counter (OTC) medications were associated with an increased risk of medication side effects (van den Brent et al., 2000). Doctors in prescribing, and pharmacists in dispensing, have an important role in detection and education. Greater awareness and knowledge of health professionals including doctors and pharmacists as well as patients is also important. Identified risk factors for medication side effects, identified in the Melbourne study were increased education level, co-morbidities and health service factors including recency of visiting the pharmacist, attending younger doctors and their doctor's awareness of their medications (Thomson et al., 2010). [QI 7, QI 12, QI 19, QI 21]

People with mental illness and mental illness and intellectual disability would be

expected to report numerous complaints associated with the medications they take and the oculo-visual anomalies they exhibit during the initial case history and the review. A retrospective analysis (Donati et al., 2009) of all medical records for patients (n = 202) with intellectual disabilities or intellectual disability and mental illness (MI) i.e., Dual Diagnosis (DD) and who were prescribed psychotropic medications was undertaken to determine the frequency of ocular anomalies, drugs taken, and complaints reported by patients during the initial review of systems. The most common documented side effects for the targeted drug types were decreased or blurred vision (near or far), visual hallucinations, decreased accommodation, and eyelid/conjunctiva irregularities. The most frequently encountered complaints for the patients were no complaints (45.16% MI and 46.84% DD), blurry vision (17.74% MI and 17.72% DD) and need new glasses (11.29% MI and 17.72% DD). The data from this study suggest that only about 50% of those who should have complaints actually report them. This would confirm the wider experience that people with intellectual disabilities have difficulties describing side effects of medications. [QI 15, QI 19, QI 21]

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