Study protocol: a cluster randomized controlled trial to assess the effectiveness of a therapeutic educational program in oral health for persons with schizophrenia

Schizophrenia is a severe mental disorder that affects 1 % of the world’s population [1, 2], including 600,000 people in France. Schizophrenia is characterized by a set of different symptoms varying in intensity: the most dramatic are delusions, hallucinations, mental dissociation, and, for the most handicapping, social withdrawal, denial of the body, and cognitive difficulties [3]. Persons with schizophrenia (PWS) have excess mortality (their life expectancy is reduced by 20 %) and excess morbidity [4, 5]. Among somatic comorbidities in PWS, poor oral health has been reported by many authors and contributes to the overall poor health of these patients [6‐8]. Generally, the symptoms of schizophrenia lead to disturbances in the progression of thought, errors in contextual analysis and errors of logic. Often, PWS do not recognize their health needs and delay seeking advice or treatment [9].

This is the case for all related somatic disorders that, by lack of analysis inherent to this disease, prevent the persons from recognising the condition or cause them not to make the right decisions to solve problems independently [9, 10]. Moreover, difficult relationships with professional caregivers (fear of mental illness, lack of training) and the health system in general (difficulties in gaining access to private practice, environment, cost…) are additional obstacles contributing to deficient somatic care [11, 12].

One of the most visible elements of poor oral health is edentulousness, and a large number of missing or decayed teeth (leading to pain, infection, masticatory and digestive problems) can be noticed in this population [13, 14]. Dental caries, periodontal or infectious diseases on the one hand, and metabolic disturbances induced by antipsychotic treatments (diabetes, obesity, xerostomia…), poor diet and lifestyle behaviours (diet rich in sugars, use of psychoactive substances such as tobacco, and inadequate oral hygiene), all combine to lead to poor health [14‐16].

Generally, negative symptoms, age, duration of mental illness, xerostomia, low socio-economic and cultural determinants are risk factors common to tooth decay and periodontal disease [17‐21]. These factors are aggravated by stigmatization and discrimination, which is why PWS do not have the same amount of attention, in terms of their physical health, as others [22, 23]. International data confirm that oral health is poor in PWS. Dental caries and periodontal measurement indexes are often twice the level found in the general population [8, 14, 20, 21]. Generally speaking, less than 10 % of the population of industrialized countries suffer from severe forms of periodontitis [24, 25]. Periodontal health is assessed using different indexes. The periodontal index, called the CPI (community periodontal index), is the World Health Organization’s (WHO) reference index [26]. It is estimated that 40 % of schizophrenics exhibit a CPI ≥ 3 according to the literature [27, 28]. A CPI ≥ 3 indicates advanced periodontal disease, with a loss of alveolar bone depending on severity. The most consistent predictors of periodontal disease are age, education, income, smoking status, dental visits, the number of remaining teeth, the number of decayed coronal surfaces, the number of decayed root surfaces and diabetes. Periodontal disease is therefore influenced by medical, social and behavioral factors [29, 30]. Appropriate treatment to control periodontal infection can limit the number of affected sites and stop the progression of the disease [31]. For the management of oral health problems, it is important to control the frequency of daily brushing and the side effects of antipsychotic treatments, to ensure regular dental visits and to monitor the respect of dental hygiene advice [32].

Poor oral health can also affect quality of life through the social and psychological impact of the deterioration in smile aesthetics for self-esteem, and self-confidence [8, 22]. The oral side effects of antipsychotics generally include a reduction in the salivary flow rate. Conversely, Clozapine can induce hypersalivation. However, a dry mouth was the chief complaint among 40 % of the psychiatric patients while dental pain was the main complaint among 60 % of the control group [33].

There are also the neurological effects of first-generation antipsychotics (FGAs) (dystonia, dyskinesia), which produce shaking and prevent effective brushing, alter chewing and swallowing [34, 35]. Second-generation antipsychotics (SGAs) induce more metabolic side effects and fewer neurological effects [36, 37]. Evidence of a relationship between metabolic disorders and oral deficiencies has gradually grown over the last 10 years with, on the one hand, increased knowledge on the pathophysiology of the syndrome and its consequences on cells and tissues and, on the other hand, the observation that certain infectious diseases of the mouth, such as periodontal disease, have already been associated with each of the components of the metabolic syndrome [38]. This means that diabetes is a risk factor for the development of periodontal disease. Control of periodontal infection would furthermore contribute to controlling diabetes [39‐41]. Periodontal disease is also a risk factor for cardiovascular diseases (ischemic heart disease) and associated with excess mortality in PWS. One explanation is that poor oral hygiene allows oral bacteria to enter the bloodstream. Immune complexes are then formed, which, in turn, elicit inflammatory responses in arteries [42, 43]. Furthermore, oral health is not just about having healthy teeth, it is a ‘standard of health of the oral and related tissues which enables an individual to eat, speak and socialise without active disease, discomfort or embarrassment and which contributes to general well-being’. Oral health is thus inseparable from general health, and managing oral health problems needs a multidisciplinary approach. Currently, oral health prevention and promotion programs, based on knowledge in the general population and transposed for persons with severe mental disorders, have not proven to be very effective [44‐46]. The particular profile of persons suffering from schizophrenia must be taken into account. Khokhar et al. [45] pointed out that there were no studies with a high enough level of proof to support current practices in this field.

The research deals with ways to help persons with smoking, a sedentary lifestyle, unbalanced diet, and dental health status [47‐49]. This requires people, especially the family circle, social, medical and social services personnel, private nurses and general practitioners [50‐52], to be trained to interact frequently with such patients. This training is particularly necessary because healthcare professionals often have an aversion to these patients (fear of the mental illness, lack of training), leading to numerous biases and generating an unhelpful attitude. The lack of initial training in this field contributes to misunderstanding among caregivers and the stigmatization of patients suffering from schizophrenia [12, 52]. It is therefore important not only to build awareness of oral health problems in PWS, but also to train these caregivers in psychiatric diseases. The aim of this training would be to foster better understanding of patients’ symptoms in order to avoid misunderstandings regarding their behaviour.

In response to the increased prevalence of chronic diseases, the very high rate of treatment non-observance, and the need for more personal autonomy, therapeutic education (TE) with small groups (five or six participants) is gradually emerging as a healthcare approach [53, 54].

For example, Lindenmayer et al., showed the effectiveness a structured wellness program using a psychoeducational curriculum for weight reduction and other metabolic markers in a large inpatient sample (275 patients with severe mental illness) [55].

According to the World Health Organization (WHO), the aim of TE is to help patients take care of themselves and to improve empowerment and recovery [54]. In this educational approach, it is important to take into account the experiences of persons taking part in multidisciplinary group learning. In a preliminary study, we confirmed the acceptability and feasibility of partnerships with PWS to develop an interactive guide to improve access to primary care providers for chronic disease management and health promotion [56]. TE is too often limited to cognitive information or movement training. Health beliefs are often not studied and the presentation of the causal links between inadequate behaviour and chronic disease is largely insufficient to treat a patient successfully over the long term [57, 58]. A new approach to TE programs depends on a specific environment to foster motivational behaviour change, not only “focused” on patients but developed with them. In this model, the person is the best expert of the disease. In the TE concept, as participants themselves are trying to learn, one can explore not only what the participants are talking about, but also how they are trying to understand and conceptualize the issue under discussion [59, 60].

Rarely investigated, the PWS experience in oral health quality of life (OHRQoL), must be used to build an educational therapeutic program in oral health in a small multidisciplinary group learning process.

The principal objective of this study is to evaluate the effectiveness of a therapeutic education programme in oral health (TEPOH) for PWS. This aim will be achieved in the context of a randomized controlled cluster study using a population with schizophrenia sample recruited from out- or in-patients in psychiatric hospitals in France.

We hypothesize that a multidisciplinary therapeutic education program (TEP), involving dentists, psychiatrists, nurses, doctors, psychologists, PWS, caregivers and specialists in therapeutic education, will promote clinical improvements in oral health. In addition, we will assess TEPOH as a new care support strategy for improving the oral health related quality of life (OHRQoL) of PWS. We will also assess caregiver’s behavioural changes concerning oral health in PWS.

It is a multicentre, cluster randomized controlled trial designed to assess the effectiveness of a TEPOH on PWS. Therefore, 12 hospitals will be randomly allocated to four clusters (a cluster is composed of three hospitals) where benefiting from TEPOH is available or not, and 230 PWS will be recruited and randomly allocated with a ratio of 1:1 to one of two conditions: control without intervention versus the group benefitting from TEPOH.

The active participation of patients is a key component of the study. However, the major difficulties with the inclusion of PWS in a long-term protocol study is that many PWS may be unable to cooperate due to their psychiatric illness, or lost to follow-up, or die during the study.

Secondly, although oral health has an impact on general health, self-esteem and quality of life often have a low priority in persons with psychiatric diseases in France. Furthermore, the somatic care of patients undergoing psychiatric treatment remains heterogeneous.

In this case, a key component will be the participation and involvement of healthcare teams in introducing TEPOH in their practices and in promoting TEPOH in all units of the hospital.

The preliminary phase of the study is completed and data collection for patients is closed. We will proceed with randomization of the clusters and will include the first patients in the study during July, 2016.