Understanding the knowledge, attitudes and practices of providing and receiving nutrition care for prediabetes: an integrative review

Additional keywords: healthcare providers, primary care, type 2 diabetes mellitus.

Prediabetes presents an opportunity to decrease the incidence and economic burden of type 2 diabetes mellitus (T2DM) and the associated health complications (World Health Organization 2006). The World Health Organization (WHO) recognises prediabetes as a condition where an individual has an impaired glucose tolerance (IGT) reading of <7.0 mmol L^–1 or impaired fasting glucose (IFG) of 6.1–6.9 mmol L^–1 (World Health Organization 2006). Guidelines from international and national health authorities recommend that individuals make dietary and other behaviour changes given positive outcomes from lifestyle modification observed in longitudinal studies (World Health Organization 2006; Gillies et al. 2007; International Diabetes Federation 2012; Diabetes Australia 2015). The Diabetes Prevention Program (USA), Diabetes Prevention Study (Finland), Indian Diabetes Prevention Program and China Da Qing Diabetes Prevention Study have demonstrated that individuals with prediabetes can reduce their risk of developing T2DM by up to 58% when they engage in lifestyle or pharmacological interventions (Tuomilehto et al. 2001; The Diabetes Prevention Program Research Group 2002; Ramachandran et al. 2006; Gillies et al. 2007; Li et al. 2008). Individuals diagnosed with prediabetes should therefore be supported to change their lifestyle behaviours, including improving diet quality, with the aim of preventing a progression to T2DM.

The International Diabetes Federation (IDF) estimated that 352 million people globally were living with prediabetes in 2017 (International Diabetes Federation 2017), which suggests interventions need to be population-wide and easily accessible. The most appropriate place to provide prediabetes management activities is the initial point-of-contact between individuals and healthcare systems, known as primary care (Keleher 2001; American Academy of Family Physicians 2018). International guidelines from the WHO (World Health Organization 2016) and IDF (International Diabetes Federation 2012) recommend that primary healthcare providers (HCPs) screen, diagnose and manage prediabetes in order to prevent T2DM. National guidelines from the American Diabetes Association (ADA) (American Diabetes Association 2018), Diabetes Canada (Diabetes Canada Clinical Practice Guidelines Expert Committee 2018), Diabetes UK (National Institute for Health and Care Excellence 2015) and Australian Diabetes Society (Colagiuri et al. 2009) echo these recommendations and prioritise lifestyle interventions over pharmacological treatment. A key component of the recommended lifestyle interventions for T2DM prevention is nutrition care, which refers to any practice conducted by a HCP that aims to support patients to improve their diet quality (Ball et al. 2012).

Individuals with prediabetes who receive individualised nutrition care or attend group nutrition education sessions experience superior weight and blood glucose outcomes than individuals receiving ‘usual care’ (Parker et al. 2014; Sun et al. 2017), which includes general advice, but no specific, individualised treatment plan (Harlapur and Shimbo 2013). Guidelines specifically recommend that GPs refer individuals with prediabetes for individualised nutrition care, with a trained dietitian where feasible, or to a group education program for diabetes prevention (International Diabetes Federation 2012; The Royal Australian College of General Practitioners 2016; American Diabetes Association 2018; Diabetes Canada Clinical Practice Guidelines Expert Committee 2018). Although patients reportedly prefer to receive individualised nutrition care rather than general advice (Ball et al. 2014; Endevelt and Gesser-Edelsburg 2014; O’Brien et al. 2016; Sladdin et al. 2017), it is unclear what type of support is provided to and received by people with prediabetes. One recent integrative review of 10 studies by Youngs et al. (2016) explored the effect of a prediabetes diagnosis on lifestyle change behaviour. The researchers found that further education and individualised support is required to motivate individuals with prediabetes to change their behaviour (Youngs et al. 2016). While these findings are important, this study did not include the HCP perspective, and only assessed the effect of a prediabetes diagnosis on an individuals’ perceived ability to change behaviour (Youngs et al. 2016). No studies have yet synthesised the literature on nutrition care for prediabetes from both the HCP and patient perspective.

The aim of this study was to integrate the literature on knowledge of nutrition care for prediabetes, attitudes towards providing nutrition care in this context and actual nutrition care practices. By synthesising the perspectives of both HCPs and patients, we can advance our understanding of current practice to identify opportunities to optimise interventions to reduce the incidence of T2DM.

An integrative literature review was conducted for a comprehensive analysis of both qualitative and quantitative studies (Broome 2000; Souza et al. 2010). This approach is common in healthcare research and is more thorough than a traditional systematic review, as it allows for the simultaneous analysis of a variety of study designs and populations (Broome 2000; Whittemore and Knafl 2005; Souza et al. 2010). The review protocol was registered with the International Prospective Register for Systematic Reviews (PROSPERO), registration number: CRD42018103333. PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) was used to display the search strategy. The guidelines by Whittemore and Knafl (2005) were used to ensure a systematic, rigorous approach (Souza et al. 2010). The SPIDER tool (Sample, Phenomenon of Interest, Design, Evaluation and Research type) (Cooke et al. 2012) was used to identify the guiding question ‘What are patients’ and healthcare providers’ (HCPs) knowledge, attitudes and practices around nutrition care for prediabetes in primary care?’.

A systematic literature search was conducted between December 2017 and February 2018 with assistance from a health librarian. Six databases were searched based on their relevance to the review topic; The Cumulative Index of Nursing and Allied Health Literature (CINAHL), MEDLINE, Embase, PsycINFO, Scopus and ProQuest. Search terms relating to experiences, knowledge, awareness and perceptions were paired with search terms for prediabetes, including ‘prediabetes or pre-diabetes’, and the MESH term ‘prediabetic state’ in two databases. A detailed search strategy is outlined in Table 1. The search terms for impaired glucose tolerance (IGT) and impaired fasting glucose (IFG) were not used because after initial screening, it was apparent that the key articles were identified by the term ‘prediabetes’ alone, while ‘IGT’ and ‘IFG’ identified articles not relevant to this review. A previous integrative review on behaviour change among individuals with prediabetes used a similar search strategy (Youngs et al. 2016). Although the current review focussed on both patients and HCPs, it was decided that including these terms in the search might unnecessarily limit the findings, and they were applied at the screening stage instead.

Table 1.  Search strategy

Articles were included in the review if they: (i) focussed on the condition of prediabetes as diagnosed by the WHO or ADA criteria, including IFG or IGT; (ii) involved adults (>18 years) of any ethnicity or gender who identified as either patients or HCPs; (iii) assessed current nutrition care practices; and (iv) were available in full-text English, peer-reviewed and were published after 2002. This was the year that the ADA (American Diabetes Association 2018) defined prediabetes as a state of elevated risk for T2DM, based on the results of the Diabetes Prevention Program study (The Diabetes Prevention Program Research Group 2002; Dagogo-Jack 2005; Twigg et al. 2007). Articles were excluded if they did not focus on nutrition care for a prediabetes population, did not involve a primary care interaction or were of the wrong study design (i.e. not an observational study). Randomised controlled trials and intervention studies were excluded as they do not reflect usual care, which was the aim of this study. Articles that examined prediabetes along with other conditions, such as T2DM, were eligible if they presented the prediabetes data separately. Articles that used terminology such as ‘high risk’ or ‘moderate risk’ of T2DM, without explicitly defining prediabetes, were excluded. The inclusion and exclusion criteria are outlined in Table 2.

Table 2.  Inclusion and exclusion criteria

The search results were imported into EndNote (Clarivate Analytics, Philadelphia, PA, USA) from each database, along with two additional articles found through manual searches. Duplicates were removed electronically from EndNote and then manually removed based on title matching. The results were imported into the online evidence synthesis software, Covidence^®, (Melbourne Vic., Australia) for title and abstract screening. Titles and abstracts were screened in duplicate based on inclusion and exclusion criteria. When conflicts arose, researchers met to review the criteria and a mutual decision was made to include or exclude the article for full-text screening. Full texts of articles were analysed independently by two researchers to ensure they met the criteria. Conflicts that could not be resolved through discussion went to a third, independent researcher. Data were extracted using a standardised table to display study attributes, including authors, year, setting, study design, sample characteristics and aims.

Quality assessment of articles was completed in duplicate using the Mixed Methods Appraisal Tool (MMAT), which is a straightforward scoring system for mixed methods reviews (Pluye et al. 2009). Results were compared and conflicts resolved through discussion with a third researcher. Articles were given a score based on the MMAT scoring metrics guidelines, and are reported in the data synthesis tables (Tables 3 and 4).

Table 3.  Overview of studies with quantitative designs
↓, decrease or lower; ↑, increase or higher; , mean; ADA, American Diabetes Association; BMI, body mass index; CHO, carbohydrates; DPP, diabetes prevention program; EMR, electronic medical record; F, females; HCP, healthcare provider; IFG, impaired fasting glucose; LS, lifestyle; M, males; NHANES, National Health and Nutrition Survey; OAD, oral anti-diabetic drug/s; PA, physical activity; PDM, prediabetes; pt., patient/s; RCT, randomised control trial; SES, socioeconomic status; T2DM, type 2 diabetes mellitus; USDA, United States Department of Agriculture; wt., weight; y, years

Table 4.  Overview of studies with qualitative and mixed-method designs
ADA, American Diabetes Association; DPP, diabetes prevention program; EMR, electronic medical record; HCP, healthcare provider; IGT, impaired glucose tolerance; LS, lifestyle; NHANES, National Health and Nutrition Survey; OAD, oral anti-diabetic drug/s; PDM, prediabetes; pt., patient/s; T2DM, type 2 diabetes mellitus; wt., weight

A systematic approach was used to simultaneously analyse qualitative and quantitative data, following integrative review guidelines by Whittemore and Knafl (2005). Three investigators (M. Somerville, L. Ball and L. T. Williams) performed the data analysis phase to ensure methodological rigour. First, data reduction was performed to divide the data based on methodological design (qualitative, quantitative or mixed method). A predetermined set of subgroups were used to categorise each study, based on the research aim: (i) knowledge and attitudes of nutrition care; (ii) barriers around nutrition care; and (iii) nutrition care practices. Based on these categories, extracted data from each included study was grouped, coded and compared to determine common relationships. Finally, descriptive synthesis was performed to report common themes and display the data. Table 3 presents quantitative findings related to nutrition care, such as percent of HCPs who provided dietary advice or percent of patients who engaged in weight loss behaviours. Qualitative study results reported as themes related to nutrition care for prediabetes are shown in Table 4.

A total of 12 851 studies were identified by the search. Full-text articles were retrieved for 108 studies, 26 of which met the inclusion criteria (Fig. 1). Most of the excluded studies did not focus on nutrition care (n = 42) or did not involve a prediabetes population (n = 20) (Fig. 1). The included studies were published between 2002 and 2018, with the majority (n = 22) published in the past 10 years. Most studies were conducted in the USA(n = 15), with the others in the UK (n = 4), Canada (n = 2), Denmark (n = 2), India (n = 1), Switzerland (n = 1) and Israel (n = 1). Designs of the included studies were quantitative (n = 18), qualitative (n = 7) and mixed methods (n = 1). Qualitative study methods included semi-structured interviews (Troughton et al. 2008; Hindhede and Aagaard-Hansen 2015; O’Brien et al. 2016; Hafez et al. 2017; Kandula et al. 2018), focus groups (Williams et al. 2004) or both (Hindhede 2014). One mixed-methods study involved semi-structured interviews, focus groups and questionnaires (Wylie et al. 2002).

Fig. 1.  PRISMA flow diagram.

Ten studies reported data on patients only (Troughton et al. 2008; Endevelt et al. 2009; Geiss et al. 2010; Dorsey et al. 2011; Yang et al. 2011; Harris and Chew 2014; Kolb et al. 2014; Hooks-Anderson et al. 2015; Okosun and Lyn 2015; O’Brien et al. 2016), nine reported data on HCPs only (Wylie et al. 2002; Williams et al. 2004; Fearn-Smith et al. 2007; Curran et al. 2008; Basavareddy et al. 2015; Mainous et al. 2016; Mehta et al. 2017; Tseng et al. 2017; Kandula et al. 2018) and seven studies provided data on both patients and HCPs (Strychar et al. 2006; Bovier et al. 2007; Cloney et al. 2011; Hindhede 2014; Anderson et al. 2015; Hindhede and Aagaard-Hansen 2015; Hafez et al. 2017).

Sample sizes ranged from 10 to 43 participants in the qualitative studies and 122 to 210 365 participants in the quantitative studies. Both males and females were represented in studies involving HCPs, with a general trend of more male HCPs, except in one study where only 27.7% of survey respondents were male (Tseng et al. 2017). Among the studies that examined patients’ perceptions or behaviours, the proportion of male-to-female participants varied greatly, while the majority of patients were aged >45 years (Tables 3 and 4).

Quality assessment of all studies revealed a range of scores from low (*) to high (****). Quantitative study designs tended to rank higher than qualitative studies based on the MMAT scoring tool (Pluye et al. 2009). Reasons for low scores among the qualitative studies included poor description of participant selection (Wylie et al. 2002; Williams et al. 2004; Hindhede 2014; Hindhede and Aagaard-Hansen 2015; Hafez et al. 2017) and a lack of researcher reflexivity in how their interactions with participants may influence results (Williams et al. 2004; Troughton et al. 2008; Hindhede 2014; Kolb et al. 2014; Hindhede and Aagaard-Hansen 2015; O’Brien et al. 2016; Hafez et al. 2017). Quantitative studies received low scores for having a low response rate or complete outcome data (Strychar et al. 2006; Fearn-Smith et al. 2007; Endevelt et al. 2009; Kolb et al. 2014; Mainous et al. 2016; Mehta et al. 2017), reporting a sampling strategy that was irrelevant for the population under study (Basavareddy et al. 2015; Mehta et al. 2017; Tseng et al. 2017) or for failing to adequately report inclusion or exclusion criteria (Fearn-Smith et al. 2007; Basavareddy et al. 2015; Tseng et al. 2017).

Five themes emerged from the data: (1) nutrition care is preferable to pharmacological treatment; (2) patients report taking action for behaviour change; (3) HCPs experience barriers to providing nutrition care; (4) HCPs tend not to refer patients for further nutrition care; and (5) patients and HCPs have opposing reports of receipt and provision of nutrition care.

Patients preferred nutrition care, including support for weight management and dietary changes, over pharmacological treatment, and expressed the benefits of improving diet for overall health, not just diabetes prevention (O’Brien et al. 2016). HCPs also reported preferring interventions focusing on diet, weight management and exercise over pharmacological intervention (Basavareddy et al. 2015; Kandula et al. 2018) or recognising the importance of lifestyle modification as the primary approach to prediabetes management (Curran et al. 2008; Mainous et al. 2016; Hafez et al. 2017; Tseng et al. 2017). Where nutrition care was the preferred treatment approach, HCPs believed that prediabetes treatment was economically beneficial and that when treated, patients in their clinic returned to normoglycemia (Basavareddy et al. 2015). Patients identified a preference for group nutrition education; consistent, structured and accurate nutrition information; and valued HCPs spending time on tasks regarding nutrition more than written material (Troughton et al. 2008). Patients requested more individualised support and guidance from HCPs to help make improvements to their diet, with one participant stating ‘I find dieting really hard’ (Troughton et al. 2008). Some suggested introducing a specialist prediabetes service, which would include appropriate nutrition care, along the lines of family planning preventive services (Troughton et al. 2008).

Patients frequently reported changing their lifestyle behaviours to be in line with recommendations, including attempting to control or lose weight (Bovier et al. 2007; Geiss et al. 2010; Dorsey et al. 2011; Yang et al. 2011; Harris and Chew 2014; Kolb et al. 2014; Okosun and Lyn 2015) and making changes to their diet (Bovier et al. 2007; Yang et al. 2011; Okosun and Lyn 2015). However, long-term success rates were low for some attempted behaviour change (Okosun and Lyn 2015). In one study, investigators suggested the modest findings in terms of behaviour change could be attributed to the lack of behaviour change training received by HCPs (Bovier et al. 2007). Several studies reported a positive association between HCP advice to engage in lifestyle modification, such as weight management or dietary changes, and actual patient behaviour (Geiss et al. 2010; Yang et al. 2011; Okosun and Lyn 2015), especially among individuals attending a preventive care visit with a HCP (Harris and Chew 2014). One study reported no significant association between HCP advice to change lifestyle and patient behaviour (Dorsey et al. 2011).

Healthcare providers identified several barriers to providing nutrition care. They reported not having enough time in consultations to provide diet advice (Williams et al. 2004; Fearn-Smith et al. 2007; Mainous et al. 2016; Tseng et al. 2017; Kandula et al. 2018) and felt that their patients had inadequate access to nutrition programs or resources (Williams et al. 2004; Mainous et al. 2016; Tseng et al. 2017; Kandula et al. 2018). In two studies involving HCPs, participants expressed having limited time and resources specifically available in primary care for providing preventive services, including nutrition counselling for prediabetes (Wylie et al. 2002; Williams et al. 2004). They felt these practices to be inappropriate for a primary care setting, and saw them as the responsibility of health promotion and societal change (Wylie et al. 2002; Williams et al. 2004). Other HCPs identified the lack of patients’ ability to change (Mainous et al. 2016; Kandula et al. 2018) or the low levels of patient motivation and self-efficacy as barriers to providing lifestyle advice (Wylie et al. 2002; Williams et al. 2004; Fearn-Smith et al. 2007; Mainous et al. 2016; Kandula et al. 2018). One study found that HCPs strongly agreed with the statement ‘I find that lifestyle changes are hard for patients to maintain in the long run’ (Fearn-Smith et al. 2007). Participants with prediabetes from two studies also reported challenges to behaviour change, expressing frustration when weight loss or attempts to change diet were unsuccessful (Hindhede 2014; Hindhede and Aagaard-Hansen 2015).

The fourth theme revealed that it was not common practice for HCPs to refer patients for individual nutrition counselling, such as to a dietitian or diabetes educator (Strychar et al. 2006; Endevelt et al. 2009; Cloney et al. 2011; Anderson et al. 2015; Tseng et al. 2017) or to a community behaviour change program (Strychar et al. 2006; Hooks-Anderson et al. 2015; Hafez et al. 2017; Mehta et al. 2017; Tseng et al. 2017). In fact, in one study, none of the 168 patients with prediabetes were referred to a diabetes educator, despite the fact that one worked at the same site as the HCPs (Anderson et al. 2015). Patient and provider characteristics were associated with referral patterns. In one study conducted in the USA, higher rates of referral to diabetes education was associated with being black (Hooks-Anderson et al. 2015), while having a BMI >30 kg m^–2 was positively associated with referral for individual nutrition counselling in another USA study (Cloney et al. 2011). This study found that non-physician providers referred patients for nutrition counselling more often than physicians, although the difference was not statistically significant (Cloney et al. 2011).

The final theme focuses on the seemingly opposing findings between patients and HCPs regarding nutrition care. HCPs reported providing lifestyle, dietary or weight loss advice to patients often (Strychar et al. 2006; Basavareddy et al. 2015; Hafez et al. 2017; Mehta et al. 2017; Tseng et al. 2017), while patients stated they seldom received lifestyle, dietary or weight loss advice in consultations (Strychar et al. 2006; Geiss et al. 2010; Yang et al. 2011; Harris and Chew 2014; Mehta et al. 2017). At the same time, patients reported high levels of motivation to make lifestyle changes with a prediabetes diagnosis (Troughton et al. 2008; Hindhede 2014; Kolb et al. 2014; Hindhede and Aagaard-Hansen 2015; O’Brien et al. 2016), with some referring to their prediabetes diagnosis as a ‘wake-up call’ (O’Brien et al. 2016). While HCPs recognised the importance of lifestyle change, they reported the weight loss, diet and exercise recommendations were unrealistic for most patients (Kandula et al. 2018). Unsurprisingly, some patients expressed frustration because they were motivated to change but received little or inconsistent advice from their HCP around how to change their diet or lifestyle (Troughton et al. 2008). A retrospective evaluation of chart entries in a family practice clinic and an endocrinology clinic revealed that lifestyle advice was often provided during an initial consultation, but follow-up nutrition care was low for all patients, and that specific diet and weight loss advice was offered to less than one-quarter of all patients with prediabetes (Anderson et al. 2015).

Some studies found that certain patient or provider characteristics were associated with the provision of nutrition care. Investigators of one cross-sectional study conducted in Israel found patients who receive nutritional counselling from a dietitian tended to be female, aged 45–64 years and were from a high socioeconomic status area (Endevelt et al. 2009). A chart audit study comparing the practices of two clinics in rural USA revealed that lifestyle management was provided more often in an endocrinology clinic compared with family practice clinic; however, patients received more specific advice at the family practice clinic (Anderson et al. 2015).

While the reports of nutrition care provision differed between HCPs and patients, the specific dietary advice given by HCPs was comparable across all studies. The most common dietary advice given by HCPs was to reduce fat (Geiss et al. 2010; Dorsey et al. 2011; Yang et al. 2011; Basavareddy et al. 2015; Okosun and Lyn 2015) and calories (Geiss et al. 2010; Dorsey et al. 2011; Yang et al. 2011). Survey results from one study with various HCP types in India further reported recommendations to reduce carbohydrates and to increase fibre, vegetables and protein (Basavareddy et al. 2015).

To understand what is happening in primary care practice in terms of nutrition care for prediabetes, 26 articles were critically analysed to reveal five themes that describe the nutrition care for prediabetes from both the perspective of HCPs and patients. By using an integrative review methodology, and synthesising data from both qualitative and quantitative studies, a broad understanding of the topic has been obtained.

The reviewed studies indicate discrepancies between the care experienced by patients and the care reported by HCPs. HCPs’ attitudes towards nutrition care and reported provision of nutrition care do not reflect their documented behaviours or the care reported by patients. Previous studies have echoed these discrepancies between the attitudes of HCPs and actual practices around providing nutrition care in practice (Kushner 1995; Wynn et al. 2010), including for specific conditions like adolescent obesity (Story et al. 2002) and chronic kidney disease (Munuo et al. 2016). Barriers to providing nutrition care by HCPs have been reported in the literature (Kushner 1995; Helman 1997; Moore et al. 2000) and was a common theme throughout this review. These barriers may contribute to the reported contradictions between how HCPs wish to provide care and how they are actually able to deliver care in practice. This suggests that HCPs would benefit from further support to address these barriers to providing nutrition care so that both their desires and patients’ needs are met.

Another concerning result of these discrepancies is that nutrition care for prediabetes may not be patient-centred, which is defined as ‘providing care that is respectful of, and responsive to, individual patient preferences, needs and values, and ensuring that patient values guide all clinical decisions’ (Institute of Medicine (US) Committee on Quality of Health Care in America 2001). A patient-centred approach, focusing on individualised care, is not only preferred by patients (Ball et al. 2014; Endevelt and Gesser-Edelsburg 2014; O’Brien et al. 2016; Sladdin et al. 2017), but has been shown to improve health outcomes such as reducing blood glucose levels (Parker et al. 2014), which is crucial for T2DM prevention. One contradictory theme among the findings of this review that calls into question the patient-centred approach of current healthcare services is that patients reported high levels of motivation to change behaviour based on a prediabetes diagnosis, yet HCPs reported that patients lacked motivation or self-efficacy to make the necessary lifestyle changes. A recent review by Youngs et al. (2016) reinforced the fact that patients with prediabetes are highly motivated to change but need individualised, structured support to be successful. Therefore, future strategies that advance patient-centred care may improve patients’ experience of nutrition care for prediabetes and warrant further work, as it would decrease the likelihood of progressing to T2DM and assist to reduce the incidence of T2DM.

The findings of this review also suggest that HCP practices are not in line with current guideline recommendations for T2DM prevention. Both national and international guidelines suggest lifestyle modification be the primary approach for individuals at high risk of developing T2DM (Colagiuri et al. 2009; International Diabetes Federation 2012; National Institute for Health and Care Excellence 2015; American Diabetes Association 2018; Diabetes Canada Clinical Practice Guidelines Expert Committee 2018). These guidelines recommend referral to nutrition services and provision of dietary support that is individualised and specific (American Diabetes Association 2018; Diabetes Canada Clinical Practice Guidelines Expert Committee 2018). However, this review found that referral to nutrition care services is low and any dietary advice that was offered by HCPs was general. Low adherence to practice guidelines by HCPs is a commonly documented problem in primary care practice (Cabana et al. 1999) and therefore warrants further investigation, particularly around prediabetes management.

The contradictory findings reported in this review may be due to a result of social desirability bias on the part of HCPs and patients, which is common among self-reported research (van de Mortel 2008), or could be a truly discrepant perspective between HCPs and their patients. The supporting evidence around discrepancies in HCP attitudes towards nutrition care and actual practices, combined with the ever-growing prevalence of prediabetes and T2DM (International Diabetes Federation 2017), indicates the latter; that patients are most likely not receiving adequate nutrition care in primary care practice. Further research is needed to understand exactly what patients would like out of their nutrition care experience for prediabetes, and to find out from HCPs how to best address the barriers within the current healthcare system.

A key strength of this review was the study design. An integrative review methodology allows for the inclusion of both qualitative and quantitative studies, and a diverse study population, resulting in a thorough understanding of the literature. Furthermore, articles were assessed for quality using a validated tool (Pluye et al. 2009) by two independent researchers, adding to the methodological rigour of this review process. This study also presented some limitations. Articles published before 2002 were deliberately excluded, so there may be relevant literature that was not captured in our findings. However, a time limit of 2002 was introduced to reflect the current recommendations for prediabetes management and T2DM prevention. Furthermore, the results from the four major longitudinal studies that create the evidence for prediabetes interventions were not published until this time period. Given that 21 of the 26 studies included in this review were published after 2008, it is unlikely this time limit excluded any results. Due to the large quantity of articles screened, it is possible that some articles were overlooked, as perhaps less attention was given for each step of the review process. However, because so many articles were included, the search was comprehensive and likely included all relevant articles.

In conclusion, there are gaps in the nutrition care provided by HCPs to individuals with prediabetes. While both patients and HCPs express similar preferences for prediabetes management, audits do not reflect this in practice. To improve patient outcomes and reduce the burden of T2DM, nutrition care needs to be provided in line with recommendations and with a focus on patients’ needs.

The authors declare no conflicts of interest.