Development and pilot testing of a decision aid for drivers with dementia

The rising global prevalence of dementia represents an increasingly important medical, societal and economic issue. Alzheimer’s Disease International (ADI) and the World Health Organization (WHO) identified dementia as a public health priority [1]. Worldwide, there are more than 35.6 million people living with dementia [1]. By 2050 this figure is projected to rise to 115 million and the ADI and WHO have called for a more dementia friendly society [1]. To achieve this goal there needs to be improved planning and provision for individuals living with dementia [1, 2].

Dementia is a condition characterized by impairment of memory and at least one other cognitive domain (e.g. executive function, language, praxis) which interfere with daily function and independence [3]. The incidence and prevalence of dementia increase with age [4]. Although Alzheimer’s disease is the most frequent cause of dementia, other neurological disorders can be responsible (e.g. vascular dementia, Lewy Body dementia, frontotemporal dementia). For many patients, symptoms begin insidiously and may pass unnoticed for some time [4]. As the condition progresses, the ability to drive safely is eventually lost [5]. Yet, many individuals continue to drive after receiving a diagnosis of dementia [6, 7].

As our population is ageing, the number of older drivers is increasing [8–10]. Twenty years ago, 14% of all license holders in the United States were aged 65 years or more [11]; today it is 16.3% [12]. In the United Kingdom, 18.8% of the driving population is over 65 years [10]. This dependence by older individuals upon private cars is multifactorial [13, 14]: (1) access to a car provides a sense of control, self-worth and independence [15, 16]; (2) use of a car can enhance social interactions [17]; (3) alternative forms of transport are often lacking [18]; and (4) older drivers seldom plan for retirement from driving [18]. Furthermore, driving retirement is negatively associated with depression [19], difficulty accessing services [20] and nursing home placement [21].

The subject of driving and dementia raises a range of important ethical and medico-legal issues [15, 16, 22–24]. In essence, there is a need to balance road safety with the transport requirements of our ageing population [5, 25–28]. Unfortunately, much of the literature relating to driving and dementia focuses upon safety rather than mobility [25]. Achieving the correct balance can prove elusive as, despite the existence of evidence-based clinical guidelines [29, 30], many physicians simply do not raise the topic of driving retirement with individuals living with a dementia [31–33]. The need for such discussions is underscored by the fragility of older drivers and their elevated risk of injury in car crashes [29].

The majority of older drivers do not have dementia. However, given that increasing age is the leading risk factor for developing dementia [34], it is reasonable to expect more and more drivers with dementia on our roads. Thus, there is a pressing need to assist people with dementia in their decision making regarding retirement from driving. The overall purpose of this research project is to establish how a self-administered decision aid (DA) can assist drivers with dementia make decisions about driving retirement. The primary outcome measure was decisional conflict. The secondary outcome measures were knowledge, decision, satisfaction with the decision, booklet use and booklet acceptability.

Use of such a DA promotes a shift in focus away from assessment of fitness to drive. Rather, it emphasizes the need to facilitate planning for driving retirement. Such preparation for driving retirement has been likened to a ‘Ulysses contract’ [26, 35] (Ulysses asked his crew to tie him to the ship’s mast on the condition that they ignored his pleas to be released when seduced by the song of the sirens [26]). It is anticipated that, by adopting a collaborative approach, individuals living with a dementia will be more likely to raise the subject of driving retirement with their family, carer or healthcare professional.

The mean knowledge score was 5.3 pre-booklet (SD 2.4); this rose to 5.8 post-booklet (SD 2.6) (maximum possible score = 10). When asked which driving option was preferred, participants chose: stop driving now (n = 10 pre-booklet, n = 7 post-booklet); drive less (n = 0 pre-booklet, n = 1 post-booklet); stop driving later (n = 1 pre-booklet, n = 1 post-booklet); and unsure (n = 1 pre-booklet, n = 3 post-booklet). The low-literacy decisional conflict scale results range from zero to 100 (a high score indicates high decisional conflict) [52]. A mean score of 22.5 was recorded pre-booklet (range 0–60, SD 17.1); this fell to 7.5 post-booklet (range 0–30, SD 9.7). Post-booklet satisfaction with decisions about driving retirement was high (mean 4.68/5, range 4.16-5, SD 0.3).

The purpose of this research was to establish if a self-administered DA can assist drivers with dementia make decisions about driving retirement. This pilot study provided an opportunity for individuals with dementia, who are often excluded from medical research, to express their views about the decision to retire from driving [57]. Overly restrictive study protocols often preclude the recruitment of older participants [58], and particularly people with cognitive impairment or multiple co-morbidities. Thus, individuals with dementia can be denied access to new interventions or therapies. This study helped to redress this imbalance through the development and preliminary evaluation of a DA for drivers with dementia.

Most participants completed the booklet without assistance, requiring an average reading time of 30 minutes. A concerted effort was made during the development phase to ensure the study booklet was clear, concise and sensitive to the needs (e.g. cognitive requirements) of individuals with dementia. As reported in the development of a low literacy DA elsewhere [59], simple strategies were employed to improve the readability of the DDDA and reduce the cognitive effort required [50] by using: (1) large font size; (2) active voice; (3) short sentences; and (4) simple diagrams. Consequently, a low Flesch-Kincaid reading grade level of 3.8 was achieved.

The IPDAS collaboration criteria [47] serve as a validated measure of DA quality, as well as a useful guide in the development of new DAs. The DDDA rated highly in two of three quality domains: (1) content 20/20; (2) development process 20/20; and (3) effectiveness 0/7. The final version of the DDDA booklet will be forwarded to the IPDAS instrument assessment team in Cardiff, United Kingdom [59] for an objective assessment against IPDAS quality criteria. This will serve two important functions: (1) confirm that the DDDA has undergone comprehensive and rigorous development; and (2) provide assurance that it satisfies internationally agreed standards of quality.

It is widely acknowledged that the recruitment of individuals with dementia is fraught with challenges [60, 61]. Accordingly, a limitation of this pilot study is its low sample size. An additional limitation is the absence of delayed follow-up data (e.g. six month follow-up survey). Notwithstanding these limitations, encouraging improvements in participant knowledge and decisional conflict were observed following use of the DDDA. In addition, booklet acceptability was high and qualitative feedback from participants was favorable. In view of these preliminary findings, a randomized controlled trial (RCT) has been initiated to better understand the clinical impact of the DDDA (ACTRN 12613000174785). A potential limitation of this pilot study is the nature of the literature review which informed the development of the DDDA. A systematic review was not undertaken: (1) to avoid undue replication of existing reviews; (2) as a low yield of additional relevant studies was anticipated; (3) as it was unlikely to alter the DDDA development; and (4) as it was unlikely to alter the methods, results or outcomes of this pilot study.

Discussion with individuals with dementia about driving retirement often represents a challenging clinical encounter for health professionals [24, 27]. A Pyrrhic victory may ensue whereby individuals with dementia are instructed to cease driving yet they neither heed their clinician’s advice nor return for medical review. Thus, there exists a clear need to facilitate conversations related to early retirement from driving. Ideally, such discussions would occur shortly after a diagnosis is reached. This pilot study demonstrates how a multi-faceted approach (i.e. development panel, review panel and field testing) resulted in the creation of a feasible and acceptable DA for individuals with dementia. This DDDA provides a simple and balanced outline of the benefits and risks of driving. It facilitates clarification of values, promotes planning for retirement from driving and encourages the reader to speak with their doctor. The DA resource was developed in line with the IPDAS collaboration guidelines [47] and pilot tested by drivers with dementia. However, further research is required to evaluate the impact of this DA in the target group. Accordingly, a randomized controlled trial of drivers with dementia is currently underway.

There is a need for a comprehensive and inclusive approach to older drivers with cognitive impairment [24, 27, 33, 62]. This study describes an intervention which contributes towards the achievement of an important goal: enhancing patients’ quality of life while simultaneously maintaining personal and public safety [62]. It is intended that, ultimately, the DDDA will be made freely available to patients, carers and clinicians by providing copies to (1) local, state and national healthcare authorities, (2) national road safety organizations, and (3) relevant consumer support groups. The booklet is designed to facilitate discussion about a frequently neglected issue: driving retirement by individuals with dementia. Although the focus of this study was on drivers with dementia, the methods used should guide future DA development (e.g. driving and epilepsy, driving and sleep apnea, dementia and management of finances).