Evaluation of a specialist nurse-led structured self-management training for peer supporters with type 2 diabetes mellitus with or without comorbid hypertension in Slovenia

This was a prospective pre-post interventional pilot study conducted in two Community Health Centres (CHCs) in Slovenia. The initial criteria for the selection of the CHCs was based on the objective of ensuring both urban and rural settings. The CHC Ljubljana is situated in the largest municipality and capital city of Slovenia. It serves approximately 300,000 residents and is representative of an urban setting, contributing 38.4% of Slovenia's total GDP in 2022. In contrast, CHC Slovenj Gradec, located in the smallest municipality in Slovenia, serves an estimated population of 17,000 residents, representing a rural region. This CHC contributed 6.4% of Slovenia's total GDP in 2022 [25]. This approach considered the different cultural and social environments in urban and rural areas, and acknowledged that distinct forms of peer support are acceptable in each setting [26].

The study was nested within a larger parent study, which spanned from May 2021 to December 2023. Its objective was to develop an evidence-based model of peer support for people with T2DM, with or without comorbid HTN, at the primary healthcare level in Slovenia. The peer support intervention was a prospective, mixed-methods pilot study that commenced with the recruitment of eligible individuals with T2DM and HTN through purposive sampling, with the objective of training them as peer supporters via specialist nurse-led structured self-management training. Each trained peer supporter voluntarily shared their knowledge and experience at monthly group meetings with up to 10 people with T2DM and HTN over a three-month period in the local community. Data was collected through series of interviews, focus groups, and questionnaires to evaluate the role of peer support. This involved introducing trained peer supporters, determining the relationships between peer support and patient-reported quality of life and level of empowerment, and assessing the acceptability and feasibility of the peer support intervention [27].

The study was approved by the National Medical Ethics Committee (reference number 0120–219/2019/4, approved on 24 May 2019).

Purposive sampling was employed to recruit eligible patients with T2DM, with or without comorbid HTN, from two CHCs by registered nurses and family medicine physicians. These patients were interested in serving as volunteer peer supporters. The purposive sampling method ensured that the recruited participants were suitable for the peer supporter role based on their responsibility, confidence, communication skills and willingness to collaborate with an educator from the CHC. It is important to note that peer supporters should be aware that they are not medical professionals and should not attempt to provide medical treatment or diagnosis. In the event that a situation arises that is beyond the scope of their knowledge and experience, it is recommended that they refer the recipient of peer support to a healthcare professional for appropriate care [27].

Inclusion criteria were as follows: i) a confirmed diagnosis of T2DM with fasting blood glucose (BG) value ≥ 7.0 mmol/l or venous plasma glucose ≥ 11.1 mmol/l two hours after glucose tolerance test or at any random opportunity, or glycated haemoglobin (HbA1c) ≥ 6.5% [28], ii) with or without comorbid HTN with a 7-day mean home BP values ≥ 135/85 mmHg or with 24-h blood pressure monitoring mean ≥ 130/80 mmHg [29], iii) for a duration of at least one year. This was deemed necessary in order to ensure that participants have had sufficient time to adapt to their diagnosis, understand their treatment regimen, and develop a baseline level of disease management.

Exclusion criteria included: type 1 diabetes or gestational diabetes, < 18 years of age and a documented diagnosis of cognitive decline obtained from the participant’s medical records. This diagnosis was based on comprehensive assessments of the individual’s clinical presentation, medical history, and relevant test results conducted by family physicians and other healthcare professionals.

Participation in the study was voluntary. All participants received an explanation of the study objectives and a participant information sheet that provided additional information. To participate in the study, it was obligatory to sign the informed consent form.

The self-management training was designed to empower peer supporters and equip them with comprehensive knowledge of T2DM and HTN and communication skills to provide effective peer support to other patients with T2DM, with or without comorbid HTN. The training was led by an educator with the expertise of a registered nurse with specialised knowledge in the field of health education of people with T2DM—a specialist nurse. There was ongoing consultation with the mentor-educator throughout the training, who remained their mentor while providing peer support, either in person, by telephone or by email. In addition, a specialist nurse actively promoted the awareness and value of peer support, thereby reducing the spread of misinformation and concerns about recommending it [11, 17].

The training lasted a total of 15 h over a period of 2 months and consisted of four group sessions and two individual sessions. The training was organised in small groups of 6–10 candidates and conducted in accordance with the T2DM education [30] and treatment [28] guidelines. To ensure a consistent programme, each educator led the training based on the comprehensive curriculum (Table 1). To provide a comprehensive and interactive verbal and visual learning experience and to facilitate T2DM self-management through a patient-centred approach, the educators used Diabetes Conversation Maps™. Several well-established models of health behavior, such as the Biopsychosocial Model of health and illness, were considered in the development of this effective health education tool [31].

After the group sessions, participants had two individual sessions with the educator, a specialist nurse. The focus was on analysing the themes from the group session (Table 1), reviewing the self-monitoring diary of BG and BP, assessing the knowledge gained and discussing the aims of voluntary peer support, the role of a trained peer supporter and opportunities of organising peer group meetings, and ways of further collaboration with healthcare professionals, patients, and the local community. Throughout the training, the educator taught participants how to communicate assertively and used motivational and coaching techniques to approach volunteering and working with people. At the end of the 15-h training, each participant was given four different Conversation Maps™ and a honorary certificate of the acquired title of “trained peer supporter” and CHC ambassador at the award ceremony to ackowledge the completion of the training, and to acknowledge the participants’ efforts [27]. The study flow chart is presented in Fig. 1.

The theory of change underlying the intervention was based on the hypothesis that training peer supporters would influence their knowledge, perceptions, and intentions, which in turn would lead to changes in self-management behavior and ultimately improved health outcomes. This would also enable effective delivery of peer support, resulting in behavior change and health benefits among people with T2DM, with or without comorbid HTN, receiving peer support. The theory of planned behavior [32] was used to predict and explain behavior change. Our pilot study protocol is schematically presented in Fig. 2, outlining its objectives in terms of feasibility, acceptability, and effectiveness (in the study group). The ongoing collaboration between trained peer supporters, people with T2DM, with or without comorbid HTN, caregivers in the local community, and healthcare professionals aims to make them partners in health and care.

The study lasted from May 2021 to August 2022. Data were collected from medical records, clinical measurements were conducted by a registered nurse at both the pre- and post-intervention stages, and structured questionnaires were completed by the peer supporters at entry into the study (baseline) and after completing the training. At the conclusion of the training, peer supporters were invited to complete an evaluation form as the sole method to provide qualitative feedback with quotations on their overall satisfaction with the training. Variables were observed across several categories (Table 2).

Participants underwent anthropometric and biochemical measurements at baseline and 6 months after completing the training. Measurements were performed by a registered nurse at CHC using a validated scale and blood pressure monitor. SBP and DBP were measured as recommended in the guidelines [29]. HbA1c level and fasting BG value were determined using peripheral venous blood sampling. To assess the acceptability of the healthcare intervention Sekhon et al. developed the TFA tool (Table 3) [33]. Specifically, we used a 19-items TFA questionnaire (Appendix 1) developed by Timm et al. [34], which covers all 7 domains of acceptability based on the TFA tool: affective attitude, burden, ethicality, intervention coherence, opportunity costs, perceived effectiveness and self-efficacy [33]. Each item is rated on a 5-point Likert scale, the score for each of the 7 domains and the total score range between 1 and 5. To assess knowledge about HTN and T2DM, we used validated Slovenian versions of the Hypertension Knowledge Test (HKT) [35] with 11 true/false questions and the first 14-item questionnaire of the Diabetes Knowledge Test (DKT) [36], the result of both is between 0 and 100%. The Appraisal of Diabetes Scale (ADS) [37] was used to assess the individual’s appraisal of T2D, which is diabetes-specific indicator of quality of life [38], consists of 28 items on a 5-point Likert scale yielding the final score between 7 and 35 where lower score is better.

We employed purposive sampling method to recruit approximately 40 eligible individuals (30 from CHC Ljubljana and 10 from CHC Slovenj Gradec) with T2DM, with or without comorbid HTN, to become volunteer peer supporters. Each peer supporter was expected to share their knowledge and experience with around 10 patients with the same chronic condition in their local community, potentially providing support to up to 400 patients. Considering an estimated dropout rate of 20%, we anticipated that 32 peer supporters would remain, each supporting a group of 8 patients, resulting in 256 patients receiving peer support. The power analysis was done for the sample size of patients receiving peer support for the two outcomes in that larger parent study. Specifically, for the ADS score, a planned sample size of 256 patients achieves 80% power to detect a mean difference (between pre- and post-intervention) of 1.6 using two-tailed paired samples t-test, assuming the SD of differences of 9.3 (this represents the largest possible SD if the differences in ADS scores are normally distributed, given their range is at most [-28,28]) [27].

We summarised categorical variables with frequencies and percentages, and numerical variables with means and standard deviations (SD) or medians and interquartile ranges (IQR) in the case of asymmetric distributions (determined by Shapiro–Wilk normality test and visual inspection of graphs). To compare numerical variables between pre- and post-intervention, we used paired-samples t-test (together with 95% confidence interval (CI) for the mean difference) or Wilcoxon signed-rank test in the case of asymmetric distributions. A p-value of < 0.05 was considered statistically significant.

The basic socio-demographic characteristics of the 31 trained peer supporters are shown in Table 4. Among them, 21 (67.7%) were women, with a mean age of 63.9 (SD 8.9) years. They had all been treated for T2DM for a median duration of 15.0 years (IQR 5.0 – 20.5). As a comorbidity, 24 (77.4%) peer supporters had HTN. The median duration of treatment was 8.5 years (IQR 2.8 – 18.2). Of the 31 trained peer supporters, 7 (22.6%) were treated non-pharmacologically with diet and exercise, 13 (41.9%) with hypoglycaemic agents, 5 (16.1%) with a combination of hypoglycaemics and insulin, and 6 (19.3%) with insulin alone.

Participants rated the training as highly acceptable in all 7 domains, with median scores ranging from 4.0 to 5.0 and the lowest first quartile being 4.0 (Table 5). The median total score was 4.5 with IQR (4.1 – 4.7).

Some of the quotations from the evaluation forms highlight the satisfaction with the training: “It is fascinating how much I have learned about both diseases, even though I have been living with T2DM and HTN for years;” “I can always contact my educator by mail or phone if I have a problem;” “The training encouraged me to continue with a healthy lifestyle and to take greater control of my health;” “This programme gave me additional motivation to maintain my health and to share my experiences with others;” “I believe that the Conversation Maps are great; when I showed them at home, the words about T2DM just rolled out of my tongue.”

After completing the training, knowledge of T2DM and HTN increased significantly (p < 0.001 and p = 0.024, respectively). The mean knowledge of T2DM at baseline was 72.9% (SD 15.6%, median 79.0%, IQR (64.0% – 86.0%)), the mean difference in knowledge of T2DM was 9.4% (SD 12.9%, median 8.0%, IQR (0.0% – 14.5%)) with 95% CI for the mean difference (4.7%, 14.1%). The median knowledge of HTN at baseline was 91.0% with IQR (77.5% – 91.0%), the median difference in knowledge of HTN was 0.0% but with IQR (0.0% – 9.0%).

The mean anthropometric and biochemical measurements at baseline and 6 months after completion of the training are shown in Table 6. Peer supporters' weight decreased significantly (p = 0.022) from 85.8 (SD 19.5) kg at baseline to 84.2 (SD 20.0) kg 6 months after training, and BMI decreased from 30.4 (SD 6.2) to 29.8 (SD 6.2) (p = 0.020). Changes in fasting BG, HbA1c, SBP and DBP were not significant.

Peer supporters are becoming an integral part of diabetes management. This study addresses an important gap in person-centred diabetes care by providing new insights into the feasibility and acceptability of a training programme for peer supporters. To ensure that the intervention is well organised, effective and sustained, emphasis needs to be placed on recruiting, training and retaining peer supporters for ongoing effective self-management and support of others with the same chronic condition. This can be achieved through several key strategies, including purposive sampling to select suitable candidates for the peer supporter role, the involvement of a mentor-educator to provide ongoing support and supervision, regular evaluation and monitoring of the training to identify challenges and areas for improvement, and the acknowledgement of peer supporters with honorary titles and certificates. The study provided valuable insights that could contribute to the successful implementation of peer support training interventions in diabetes care.

Our study has several limitations. Firstly, the lack of a control group of potential peer supporters who did not attend the training makes it impossible to estimate the real effectiveness of the training programme, and further research with a control group is needed. We decided not to use a control group due to our limited sources and our goal to train as many peer supporters as possible in a short period of time. Secondly, the use of the same DKT and HKT questionnaires at the beginning and the end of the two-month training means that participants already knew the questions, which could influence their actual knowledge. However, previous studies showing improved knowledge of T2DM after training [19, 43], also repeated the same test, suggesting that question familiarity is not predictive of the second test results. Thirdly, it is not possible to measure the long-term effects as the questionnaires were only measured after the training was compiled, and clinical outcomes were only measured 6 months after the training. Fourthly, we cannot say that 15 h of training is sufficient. Therefore, a follow-up evaluation is needed to examine retention and acquisition of skills and knowledge for ongoing peer support intervention. Fifthly, in anticipation of a small sample size and difficulty in recruiting a large enough sample of participants with both T2DM and HTN who were willing to become peer supporters, we included in the pilot study all individuals with a confirmed diagnosis of T2DM, regardless of whether they had comorbid HTN. In addition, the use of purposive sampling introduces potential bias and limits the generalisability of the findings. Finally, we did not formally evaluate the teaching effectiveness or information transfer skills of the peer supporters. However, to the best of our knowledge, no studies [11, 12, 18, 21, 23, 24] have included teaching skills in peer support training programmes, as the focus has been on practical and experiential skills that are crucial for managing their condition.