Celiac disease is a chronic, autoimmune, genetically predisposed gastroenterological disorder in which sensitivity to gluten leads to damage and constant inflammation of the small intestine (Ford et al., 2012). The digestion of gluten, the primary storage protein of wheat and other grains such as barley, rye and oats, leads to the destruction of the villi in the small intestine (Ciclitira et al., 2005) and an inflammatory response in the intestine that is detectable by blood testing (Woodward, 2011; Beaudoin and Zimbardo, 2012). Therefore, the surface of the small intestine weakens, and the ability to digest and absorb nutrients decreases significantly (Woodward, 2011). The disease is also associated with osteoporosis, fertility issues in women, diabetes, increased risk of gastrointestinal cancer and non-Hodgkin’s lymphoma (Ford et al., 2012). The global prevalence rate of celiac disease is approximately 1–1.4% (Mustalahti et al., 2010; Gujral et al., 2012; Singh et al., 2018), although the prevalence rate in Ireland and Scandinavian countries is higher, with a suggested prevalence rate of 2–2.4% (Mustalahti et al., 2010). However, because of different manifestations of the disease and the absence of screening, the exact numbers are not known but are expected to be significantly higher (Woodward, 2011; Ford et al., 2012; Green et al., 2015). Celiac disease is usually diagnosed through a blood sample and small intestine biopsy to detect villus atrophy (Ford et al., 2012).

The only effective treatment for celiac disease is lifelong adherence to a gluten-free diet. A gluten-free diet requires avoidance of all foods that contain wheat, rye, barley, and oats. There are still controversies around consumption of oats, although there are studies suggesting that the protein contained in oats is well tolerated by some of the patients with celiac disease up to a daily limit of 50-70 g of oats for adults and 20-25 g for children (Pulido et al., 2009; Comino et al., 2015; Spector Cohen et al., 2019). Strict adherence to the diet allows the intestinal and immune systems to heal. However, the response to this therapy is not satisfactory, and in approximately 20% of individuals, the symptoms prevail even after diagnosis due to nonadherence to a gluten-free diet (Ciclitira et al., 2005). There are various motives that are cited as reasons why patients with celiac disease do not adhere to the gluten-free diet as strictly as they should, and among the most frequent ones are stress associated with the diet, adverse effects of the diet on their social life, negative effects of the diet on their mood and increased anxiety due to having to maintain a gluten-free diet (Leffler et al., 2007). Moreover, the participants also stress the costs associated with a gluten-free diet, the difficulty of finding food outside of the home, and poor food quality (Leffler et al., 2007) as reasons for nonadherence. Furthermore, accidental exposure to gluten because of poor labeling or lack of information about celiac disease and the gluten-free diet by restaurant and bar staff members is also a source of increased frustration and even social anxiety in patients with celiac disease (Addolorato et al., 2008; Zysk et al., 2018).

The literature on celiac disease and its impact on physical and psychological well-being is broad. Studies that were focused on psychological problems revealed that patients with celiac disease suffer from depression, a lower health-related quality of life, and poorer overall psychological well-being and anxiety than those in the general population (Ford et al., 2012). Besides the three most common possible biological explanations why celiac disease might trigger or mask psychological problems, i.e., the malabsorption of nutrients essential for normal functioning of the brain, the immunological reaction and release of antibodies affecting the hypothalamus-pituitary–adrenal axis, and the extra-intestinal inflammation of the body (Beaudoin and Zimbardo, 2012), there are various psychological and cognitive reasons for higher incidents of comorbid psychological problems and reports of a lower quality of life due to chronic disease (Ford et al., 2012). For example, in a study by Addolorato et al. (2008), the researchers suggest that social phobias and avoidance of social situations are fairly standard, as the gluten-free diet can be frustrating and isolating, and diet restrictions might lead to difficulties in daily social relationships for many reasons (Addolorato et al., 2004, 2008). Furthermore, European studies suggest that lower adherence to a gluten-free diet and poor adaptation to the disease are correlated with anxiety and depression (Ford et al., 2012). A systematic study found that strict adherence to a gluten-free diet ranges from 42 to 80%, depending on the definition and assessment method (Dowd et al., 2014), which is far below the expected rates. In a study presented by the Finland University research center, the authors mention that the decentralization of celiac disease diagnostics, follow-up from tertiary centers to primary care and insufficient information about the disease and the diet are the reasons for those high numbers (Kurppa et al., 2013).

As mentioned above, the research was focused on the psychological burden associated with celiac disease, and a gluten-free diet is very burdensome. Because gluten-free diet adherence is essential in the improvement of physical and mental health, the goal of this review is to map intervention strategies that aim to change and improve psychological well-being for patients with celiac disease. The present review examines these interventions and their success in terms of gluten-free adherence and changes in health-related quality of life.

The aim of the study is to give a clear picture of the interventions for patients with celiac disease to increase gluten-free diet adherence and to analyze the success of these interventions in terms of gluten-free diet adherence and changes in the health-related quality of life. This paper includes a systematic literature review that is characterized by a systematic search process to locate all relevant published work that addresses the research question as well as systematic presentation and synthesis of the findings of the results of that research (Siddaway et al., 2019). For this reason, the following databases were searched in April 2022: Scopus, Web of Science, PubMed, and ProQuest. Academic papers were selected using the following string search: Abstract or title = “coeliac disease” OR “celiac disease” AND “gluten free diet” AND “intervention” AND “health related quality of life” AND “diabetes.” The studies must have been published from 2015 onward in the English language and in full text.

Table 1: Results generated through our initial database search.

Records were then screened using the following exclusion and inclusion criteria.

Inclusion criteria were as follows:

Exclusion criteria:

The remaining records were included in this review (Figure 1).

In the selected databases, 27 articles were identified, out of which 6 were removed automatically because of 5 duplicates and 1 article written in Hungarian. Next, we screened the articles in terms of the type of article, and another 7 articles were removed. We then assessed the articles for their eligibility given the criteria stated above, which resulted in the inclusion of 8 studies in the review.

We evaluated the quality of articles with the modified version of the Effective Public Health Practice Project (EPHPP) quality assessment tool for quantitative studies. Questions about criteria unrelated to this review were excluded. Detailed component ranking can be found in Appendix 1.

One of the main aims of the present systematic review was to get a perspective about interventions for patients with coeliac disease to increase the adherence to a gluten-free diet and to increase the health-related quality of life. We have extensively searched four databases, i.e., Scopus, Web of Science, PubMed and ProQuest, which resulted in the inclusion of eight studies that introduced interventions for this purpose. We can state that the number of possible interventions designed for adults with celiac disease that need to adhere to a life-long gluten-free diet is quite limited compared to the number of studies that focus on psychological and physiological problems associated with celiac disease. Most of these studies are cross-sectional studies that focus on the adverse effects of gluten-free diets and celiac disease on diet adherence, quality of life and higher incidences of depression and anxiety, predominantly performed by medical doctors in the research teams (Ciclitira et al., 2005; Woodward, 2011; Ford et al., 2012; Green et al., 2015).

The intervention designs differ among the selected studies, although three types of interventions, i.e., group-based, telephone-based, and online-based interventions, form the basis of interventions for patients with celiac disease. In some studies, the researchers used a combined form, where, for example, one part of the intervention was delivered online and the other part was delivered in-person. The studies share a focus on education, where the main purpose of the educational part was to increase the general awareness of celiac disease as well as to provide an explanation of reasons to adhere to a gluten-free diet. Some of the studies also focused on the improvement of physical health and implemented regular exercise (Martínez-Rodríguez et al., 2021; Dowd et al., 2022) in addition to providing tools for preparing gluten-free meals at home (Wolf et al., 2020). We can see that a multidisciplinary intervention approach might be beneficial.

Regarding the effects of those interventions on the gluten-free adherence rate, all the clinical controlled trial studies showed significant improvements in the experimental group post-intervention as well as 3 months after intervention, whereas no change was found in the waitlist-control group. Moreover, the knowledge about celiac disease and the gluten-free diet increased after the intervention. Considering the only effective treatment for celiac disease is following a gluten-free diet (Ciclitira et al., 2005; Ford et al., 2012; Mehta et al., 2018) and that strict adherence to a gluten-free diet is positively correlated to a better perceived health-related quality of life (Casellas et al., 2008; 2015), the patients might benefit from participating in various interventions. It is not surprising that the results of the studies in the systematic review indicated a positive effect of interventions on the health-related quality of life in most of the studies; however, in one study (Muhammad et al., 2021), the experimental group of participants scored lower on their satisfaction with life in dietary burdens and worries and concerns at 3 months post-intervention. The studies that showed improvement in both the gluten-free adherence scores and health-related quality of life employed a combination of methods, whereas the study intervention by Muhammad et al. (2021) consisted of 2 unstructured telephone calls with dietitians. Therefore, the direction of future research in the area of intervention for patients with celiac disease might benefit from using more structured methods for sharing knowledge in terms of information about celiac disease, diet adherence and the benefits of that adherence.

It seems that despite the inconsistencies in the procedures of various intervention programs, it could be stated that any intervention might be beneficial for those with celiac disease and a need to adhere to a lifelong gluten-free diet. The results of those studies, however, suggest that the combination of the platforms, i.e., online and/or telephone platform with a group-focused in-person education component might bring more satisfactory outcomes. Moreover, the potential benefits of the interventions conducted by a multi-disciplinary team represented by gastroenterologists, psychologists, dietitians, and other professionals might bring more positive outcomes for patients with celiac disease.

The implications for the practice of interventions for patients with celiac disease is significant. Overall, an intervention designed for chronically ill adults with celiac disease supports their adherence to a gluten-free diet, improves their quality of life, helps them overcome anxieties associated with travelling, eating outside the home, and shopping for food, and helps them decrease their level of stress and anxiety associated with the diet. Future studies should probably combine online and/or telephone platform interventions with group-based interventions to promote behavioral changes among patients with celiac disease and other chronic types of disease and could potentially bring about change in the current health system.

Regarding the possible interventions, it seems that the combination of methods might be a good option for adults with celiac disease who represent a diverse group with specific needs and preferences. Those changes might also eventually lead to changes in health insurance company policies to start supporting those that need to adhere to a gluten-free diet, as almost 51.3% of participants stated that associated costs are the burden of the disease, often resulting in non-compliance to the diet. Although, the current situation in the Czech Republic regarding supporting patients with celiac disease is very limited and the contributions are low, if any. Furthermore, there is no research in this area showing benefits of implementing those interventions in the healthcare system.

As the results of this systematic review suggest, the targeted intervention should combine the knowledge from various disciplines and explain the condition, provide dietitian information about the diet, and include some cognitive behavioral therapy techniques that would help individuals stay gluten-free.

MP performed the literature search and the preparation and final editing of the manuscript. MS supervised the literature search and the preparation of the final version. PŘ performed the literature search. MA performed the final editing of the manuscript and secured the funding for the research. RP performed the final editing. All authors contributed to the article and approved the submitted version.

This work was supported by the Cooperatio Program, research area: Psychology.

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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