GPs' attitudes to benzodiazepine and ‘Z-drug’ prescribing: a barrier to implementation of evidence and guidance on hypnotics

INTRODUCTION

Most hypnotic prescribing takes place in primary care, and the use and cost of these drugs is rising. There are large variations in hypnotic prescribing,1 with some areas of the UK having higher levels of benzodiazepine and ‘Z-drug’ prescribing (hypnotics including zopiclone, zolpidem, and zaleplon) compared with national data.

There are potential side effects of hypnotic drugs, evidence of long-term use contrary to licensed indications, and lack of evidence distinguishing short-acting benzodiazepine and newer Z-drug hypnotics.2^,3 The National Service Framework for Mental Health4 and the National Institute for Health and Clinical Excellence (NICE) in the UK5 advised monitoring of hypnotic prescribing and a cost-minimisation approach that would tend to favour short-acting benzodiazepine hypnotic use.

Despite NICE guidance, benzodiazepine prescribing rates have continued to fall over the past decade, and there has been a corresponding rise in the use of newer hypnotic drugs for insomnia over the same period.3 Although there has been considerable research into the attitudes of patients,6^–9 doctors,10^–12 and both13^,14 regarding the use of benzodiazepines, there is limited published research on patients' and practitioners' perceptions of Z-drugs.

The aim of this study was to investigate and compare GPs' perceptions of benefits and risks of benzodiazepines and Z-drugs in one large primary care trust. This study was part of a larger study investigating the reasons for variations in hypnotic prescribing and exploring methods for reducing this in a primary care trust.

METHOD

West Lincolnshire Primary Care Trust has 40 general practices serving 214 000 patients. Prescribing of hypnotics is an important quality issue for all primary care organisations. Previous attempts to address prescribing in this area met with resistance to change. To address this the authors decided to explore practitioners' beliefs about hypnotic prescribing. A survey instrument, based on a search of the literature and an adaptation of a previously published instrument, was developed to collect data.13

In 2005 a self-administered postal questionnaire was sent to all GPs on the principal (independent practitioner) list of West Lincolnshire Primary Care Trust. The questionnaire focused on practitioners' perceptions of benefits and disadvantages of benzodiazepines and Z-drugs, and preferences for management of insomnia and anxiety. The questionnaire was developed using information from a review of the literature, discussion within the project steering group, and reference to experts in the field.

Returned questionnaires were entered into a spreadsheet according to a predetermined coding frame. Data were analysed using SPSS (version 12.1). Wilcoxon's signed ranking test was used for comparison of groups.

RESULTS

Of the 107 GPs who were sent questionnaires, 84 (78.5%) responded after one reminder. Characteristics of these GPs are described in Table 1.

Responders perceived that Z-drugs were more effective in terms of patients feeling rested on waking, daytime functioning, and total sleep time, and that they were less likely to lead to side effects, particularly tolerance, addiction, dependence, daytime sleepiness, and road traffic collisions. Z-drugs were also believed to be safer for older patients (Table 2).

DISCUSSION

This was a study investigating prescribing preferences in a single primary care trust. The response rate from GP principals (independent practitioners) was high, adding to the validity of the findings in relation to local prescribing of these drugs. Although caution needs to be taken in generalising the results to other primary care organisations, the results are consistent with national changes in hypnotic prescribing.

There were significant differences between GPs perceptions of the relative benefits and risk of Z-drugs compared with benzodiazepines, with the majority of practitioners attributing greater efficacy and lower side effects to Z-drugs.

Practitioners' beliefs about relative indications, effectiveness, and safety are not determined by current evidence or national (NICE) guidance. Beliefs about evidence can prevent implementation of national guidance. The attitudes of GP responders in favour of Z-drugs help to explain the increase in prescribing of Z-drugs relative to that of benzodiazepines, a national phenomenon that is inconsistent with NICE guidance.

Despite GPs' positive attitudes to guidelines overall,15 NICE guidance continues to be variable in its implementation.16 Guidance has led to changes in prescribing of some drugs, and has been supported when it is consistent with previous practice.17 There is limited research into the effect of guidance based on new evidence that discourages past patterns of behaviour, as in this study which examined increasing use of Zdrug hypnotics. A number of factors have been identified as influencing adherence to prescribing guidance in general practice including relative safety, efficacy, practicability, and information conflicting with guidance, most importantly from the pharmaceutical industry.18

The targeted use of commercial techniques19 and meetings supported by pharmaceutical companies20 to proffer selected positive information about products early in their marketing, affects the attitudes of doctors and their prescribing behaviour.21^–23 Despite professional concerns about the credibility of such information24 and the perceived immunity of some doctors to commercial influence,25 practitioners26 and their patients27 know that prescribing is being unduly influenced.

A number of approaches could be used to implement the NICE guidance and reverse current non-evidencebased trends in relation to hypnotic prescribing. Options include delivering a clearer message related to outcomes, communicating effectively using opinion leaders and other evidenced techniques, and enabling doctors and patients to understand the true relative advantages, disadvantages, and consequences of using these drugs28 and of non-pharmacological treatments. A clearer structural context is needed in health trusts supportive of implementation.17 Further research should investigate the relationship between prescribers' attitudes and actual prescribing, and examine how to change attitudes and behaviour to improve performance. GPs need to be aware of and discuss these beliefs in the context of available evidence to make informed and collaborative decisions about their prescribing practices for insomnia.