Translation of interventions for diabetes prevention into routine clinical practice is challenging [
6,
7]. We therefore evaluated implementation of a lifestyle intervention for diabetes prevention in Dutch primary care. Based on these insights, we discuss opportunities for refining intervention delivery on the participant, provider and organisational level (Table
4).
Table 4
Opportunities for refining intervention delivery on different health care levels
Participant
| * High attendance rates in our study compared to others [ 11, 12, 22] | * Use of organisational elements that can contribute to participant compliance: |
| |
- Immediately plan next appointment during consultations
|
| |
- Persons who do not show up are contacted by the practice assistant
|
| |
- Assign 1provider in the practice who is responsible for coordination / planning of the consultations.
|
| * Lack of participant motivation experienced by providers as a major barrier for intervention implementation | * Stimulate participant motivation to change unhealthy habits: |
| | - In-depth analysis of (barriers for ) participant behavioural change to reveal starting points for refining intervention content[ 5, 6, 23]. |
| | - More attention for environmental factors promoting unhealthy behaviour[ 24] |
| | - Counselling based on shared decision making to enlarge participant empowerment[ 25] |
| | - More effort into stimulating participants to engage social support[ 5, 23, 26]. |
Professional
| * Lower participant satisfaction with GP guidance than with nurse practitioner guidance. | * Role for the nurse practitioner as the key player in guiding participant lifestyle change [ 29, 30] |
| * Lower self-efficacy of GPs regarding dietary counselling compared to nurse practittioners. | |
| * Lack of specialistic nutritional knowledge reported by nurse practitioners | * Introduce elements to fill gaps in knowledge and/or skills of nurse practitioners |
| * Nearly 40 % of the nurse practitioners report limited self-efficacy for dietary counselling | - Referral to skilled supporting staff, like dieticians[ 5] |
| | - Extend motivational interviewing course towards a specialized prevention manager training[ 31], including modules to enlarge the knowledge of nutrition and physical activity in diabetes prevention.
|
Organisation
| * Lack of counselling time and financial reimbursement regarded by providers as major bottlenecks for intervention implementation | * Consider and investigate prevention strategies that could increase cost-effectiveness [ 6], such as: |
| * Modest diabetes risk reduction compared to studies in experimental settings [ 8, 11, 12, 26]. | - More stringent criteria for participant inclusion, based on risk[ 6, 11] and / or motivation[ 27] |
| | - Group-counselling[ 8‐ 11] |
| | - A more tailor-made or patient-centred intervention structure[ 6, 35] |
| | - Integration of lifestyle interventions for different disorders[ 36] |
Participant level
In the Netherlands, patients often have a long-lasting relationship with their GP and/or nurse practitioner, whom they consider trustworthy [
14]. Individual attention from these providers may therefore lead to high compliance. In line with this hypothesis, attendance at individual consultations was high, which was also found in other studies in general practice [
9,
11]. Furthermore, drop-out in our study was modest (intervention: 14.6 %; usual care: 13.2 %) and drop-out after 1 year (intervention: 6.3 %; usual care: 7.4 %) was lower than in other prevention studies in primary care (German Praedias-study: 9.3 % [
10]; Finnish GOAL-study: 9.4 % [
9]). Completers in our study more often had a partner than drop-outs, which was also found in the GOAL study [
9].
In our study, no difference in dropout rates between the two study groups was observed. Accounting for the individuals who were lost to follow-up because they developed type 2 diabetes, the statistical power to detect small, but clinically relevant differences in dropout rates between the study groups (Cohen’s conventional effect size of 0.1 [
25]) was 0.835. It is therefore unlikely that the lack of a difference in dropout rate between the groups is explained by a lack of statistical power.
In contrast to others [
12,
13,
27], attendance at individual consultations remained high throughout our study, to which several elements in the organisation of our intervention may have contributed. First, following daily routine, appointments for the next visit were made before completing of the current consultation. Second, persons who did not show up at their appointment were contacted by the practice assistant. Third, in each practice, one provider was made responsible for correct implementation of the programme, including coordination of the consultations.
Despite the high compliance in our study, providers regarded lack of participant motivation to change unhealthy habits as an important barrier for effective lifestyle counselling. This result underlines the importance of in-depth evaluation of participant behavioural change in diabetes prevention programmes to reveal starting points for refining intervention content [
7], as was for example done by Rosal et al. [
6] and Penn et al. [
28]. Furthermore, attention should be given to the identification of environmental factors influencing participant behaviour [
29], such as the food products offered in worksite cafeterias or the availability of cycling-tracks. As was done in our study, it is recommended that counselling is based on shared decision making to enlarge participant empowerment [
30]. Moreover, participants should be stimulated to mobilize social support, which was found to be important for both achieving [
6] and maintaining change [
27]. In our study, partner support was also found to contribute to weight loss success [
23].
Professional level
A positive attitude of health care providers towards change is indispensable for implementation of innovations in clinical practice [
8]. Satisfying this condition, the majority of providers in our study was confident about diabetes prevention by lifestyle counselling in Dutch primary care. Furthermore, attendance at training sessions was high and none of the providers refused participation or withdrew from the study. It must be remarked that provider compliance may be overestimated in our study as all practices were part of an association, which as a whole decided to participate in the project. In two recent Dutch studies [
16,
31], GPs were however also found to attach high importance to chronic disease prevention.
Remarkably, drop-out was lower and increases in 2 h plasma glucose were smaller in participants receiving counselling from providers who considered the chance of success of diabetes prevention in Dutch primary care low or very low than in participants from providers who considered the chance of success medium or high. In line with these results, it was previously found in our study that a lack of motivation or confidence of providers does not negatively influence participant guidance [
26]. These results may reflect a professional attitude, in which personal barriers to diabetes prevention by lifestyle intervention do not affect participant counselling [
26]. Furthermore, a reserved attitude of providers towards prevention obviously does not imply a lack of capacity for guiding lifestyle change.
Although primary care is regarded as a highly suitable setting for disease prevention [
32], debate is ongoing about the optimal division of the workload between the GP and the nurse practitioner [
33,
34]. The lower participant satisfaction with GP guidance and the lower self-efficacy of GPs regarding dietary counselling in our study support a role for the nurse practitioner as the key player in guiding lifestyle change. As most nurse practitioners in the Netherlands provide care to diabetes patients [
16], this role is compatible with existing routines. Moreover, Dutch GPs recently reported a preference for nurse practitioners to perform preventive activities [
16]. In our study the MI-course was however only offered to nurse practitioners, which may have contributed to their skills. Furthermore, after the admission interview, participants did not meet with the GP for nine months, which may have influenced their perception of GP importance in the study.
Although our findings suggest that they are very suitable to guide participant lifestyle change, nurse practitioners in our study reported a lack of nutritional knowledge. Moreover, nearly 40 % regarded themselves as only moderately suitable for dietary counselling. Referral to dieticians may be necessary to fill these gaps and may furthermore relieve time–pressure for nurse practitioners [
6,
16]. As an alternative, the motivational interviewing course –which was considered useful and desirable by all nurse practitioners in our study- may be extended towards a specialized prevention manager training [
35], which also focuses on aspects of nutrition and physical activity in diabetes prevention. This training could then for example only be offered to a subset of highly motivated nurses, to which all GPs in a certain region can refer [
36]. A disadvantage of this latter approach is however that participants may not receive counselling from their familiar provider and/or in their own practice.
Organisational level
Most providers in our study were satisfied with both the frequency and the duration of the individual consultations. However, comparable to other studies [
6,
7], limited counselling time was regarded as an important bottleneck for programme implementation. Furthermore, although individual lifestyle interventions can save money even when effectiveness is low [
37], financial reimbursement for preventive activities is mostly lacking [
6,
31]. Moreover, in several programmes in clinical practice –including ours-, risk factor reductions were modest compared to studies in experimental settings [
9,
12,
13,
30]. In diabetes translational research, it is therefore essential to consider strategies that could increase cost-effectiveness [
7].
A first approach could be to allow less persons to participate by applying more strict ‘selection at the gates’. Following other programmes [
9,
11,
38], a FINDRISC value of 13 points was chosen in our study as selection criterium, which may have led to inclusion of individuals with a relatively healthy lifestyle. Furthermore, disturbed glucose values were not a prerequisite for participation. More stringent criteria -and thus a less favourable risk profile- leave more room for improvement and may lead to higher participant efforts [
7,
12]. In addition, pre-screening based on the motivation to change the lifestyle, –as was done in the Dutch ‘beweegkuur’ [
31]- may be useful to include only those most willing to change.
A second strategy to reduce costs and thus potentially increase cost-effectiveness is group-counselling, which was applied in several prevention programmes [
9‐
12]. However, although most providers in our study regarded primary care as an appropriate setting for group-based lifestyle interventions, attendance at group-consultations was low. This could be explained by the purely didactive nature of the group-meetings and by the fact that they were supplementary to individual counselling. In line with this hypothesis, ‘I already received enough information from the GP / nurse practitioner’ was on often-mentioned reason for missing group-meetings. In other studies however, participants also reported a preference for personal guidance [
31,
39]. Furthermore, in several group-based interventions the number of participants initially refusing to participate was not mentioned [
9‐
11]. Preceding analysis of the attractiveness of group-counselling for participants is therefore necessary.
Third, a more tailor-made counselling approach may be considered [
7,
40]. Although regarded useful and desirable by most providers, only half of the participants in our study for example favoured exercise programmes and personal dietary counselling. A better adapted or more patient-centred intervention structure may result in higher participant compliance. Furthermore, restricted offering of intervention modules may reduce costs. Based on their preferences, persons may for example participate in (a combination of) weight loss, dietary and exercise modules, offered by means of brief, intensive or group-based counselling, whether or not supported by exercise programmes or dietary guidance. However, feasilibity, acceptability and (cost-)effectiveness of such a design require further research.
Fourth, as the risks of an unhealthy lifestyle are not confined to diabetes, individuals may be enrolled in several behavioural change initiatives at the same time, which is time- and money-consuming. Integration of screening [
41] and/or intervention [
31] for different disorders is therefore recommendable, whereby general intervention modules aimed at shared risk factors may be supplemented with disease specific components.
Strengths and limitations
In our study we evaluated a wide spectrum of opportunities for diabetes prevention in Dutch primary care. The high questionnaire response rates make it unlikely that missing values have significantly influenced the results. However, when filling out the questionnaires, both participants and professionals may have been affected by recent experiences. In addition, the missing records from drop-outs and individuals with diabetes may have influenced participant outcomes. Reasons for withdrawal did not however indicate dissatisfaction among drop-outs. Self-reported outcomes of participants and providers on knowledge and skills of professionals must be interpreted with caution.