Behaviour change among people with impaired glucose tolerance: Comparison of telephone-based and face-to-face advice

Abstract

Objectives

To develop, implement and compare two lifestyle services for people at risk of developing type 2 diabetes.

Methods

Two localities were selected to implement two different service delivery models, telephone-based and face-to-face, supporting people at risk of developing type 2 diabetes. Impact was assessed by comparing weight, fasting plasma glucose and oral glucose tolerance test (OGTT) results at baseline and six months later.

Results

Both services were associated with an improvement in OGTT 2-h plasma glucose and weight. In the telephone intervention, 47.3% of participants who completed the project achieved both normal fasting plasma glucose (≤6.0 mmol/l) and normal plasma glucose levels (≤7.7 mmol/l). Participants had a mean weight loss of 3.3 kg (SD 4.3), equating to 3.4% of body weight (p < 0.001). In the face-to-face intervention, 46.3% of participants achieved normal plasma glucose (≤7.7 mmol/l) and a mean weight loss of 2.9 kg (SD 4.5), equating to 3.1% of bodyweight (p < 0.001).

Conclusions

Local health providers can adapt existing service provision and tailor it to provide lifestyle programmes for people with impaired glucose tolerance. Both service delivery models offer effective diabetes prevention although each model may cater for different population needs and a choice of services might be the preferred option.

Keywords

behaviour change diabetes prevention lifestyle interventions

Introduction

In the UK, the prevalence of type 2 diabetes (referred to as ‘diabetes’) is predicted to increase due to the rising prevalence of obesity.^1,2 Impaired glucose tolerance describes a condition with raised blood glucose but not high enough to warrant a diabetes diagnosis. People with impaired glucose tolerance have an increased risk of developing diabetes and cardiovascular disease.^3–5 Evidence from randomized controlled trials shows that lifestyle interventions for people with impaired glucose tolerance can delay or prevent progression to diabetes by up to 58% in the short term and 38% after 10 years.^6–9 Evidence suggests that positive lifestyle changes benefit those with impaired glucose tolerance¹⁰ and are cost-effective.^11,12 Offering people support to change their behaviour could reduce the prevalence of diabetes.

Despite growing evidence from translational studies^13,14 contained in international guidelines,^15,16 there is no UK-wide implementation of preventive services. Between 2009 and 2011, the NIHR (National Institute for Health Research) Collaboration for Leadership in Applied Health Research and Care (CLAHRC) for Greater Manchester behaviour change, diabetes prevention, lifestyle interventions¹⁷ worked with NHS Salford and NHS Bolton, two local commissioners to implement two service delivery models. Our aim is to describe the implementation of the two models in primary care (telephone-based and face-to-face) and assess their contribution to diabetes prevention.

Methods

Salford telephone-based service

Diabetes Care-Call is a well-established service involving non-clinical health advisors trained in motivational interviewing techniques. It developed from the Pro-active Call Centre Treatment Support randomized controlled trial,¹⁸ which demonstrated that pro-active telecarer support improves glucose control in people with type 2 diabetes.

This study included 55 participants from seven general practices who were referred on diagnosis between April and November 2010. NHS Salford's diabetes team and the CLAHRC developed a six-month, telephone-based, lifestyle intervention for people with impaired glucose tolerance to provide regular support to motivate and enable people to make positive behaviour changes. The first 45-min call was delivered by a health care professional and focused on action planning to ensure each participant understood their diagnosis, the importance of preventing diabetes and how to reduce their own risk. A six-month lifestyle goal was set together with an initial ‘mini’ goal to help begin to achieve this. Participants also received a starter pack of information, which included blood results, an information leaflet on impaired glucose tolerance and a DVD (‘Sensible portions for healthy eating’) to help people with goal setting and facilitate understanding of the disease.

The remainder of the programme was delivered by a non-clinical, dedicated health advisor. It consisted of 20-min monthly telephone calls for six months. All participants completed all calls. Following each call, supporting literature was sent out, as required, offering tailored advice appropriate to needs and lifestyle goals. All telephone calls were recorded on the electronic patient record which was accessible to health care professionals in primary and secondary care in Salford.

Bolton face-to-face service

NHS Bolton already had a team of Health Trainers successfully integrated within primary care, based in general practices. Health Trainers are a national initiative offering six-month, individualized, face-to-face behaviour change support to people at risk of developing cardiovascular disease.¹⁹ They are non-clinical staff who have received intensive training in supporting and motivating people along the behaviour change pathway.^20,21

Between August 2009 and December 2010, participants with impaired glucose tolerance were recruited from 15 general practices. Of them, 83 successfully completed the individualized intervention. General practices invited participants by letter or directly referred to the Health Trainer. Participants included people newly diagnosed as well as those whose diagnosis was made in the last few years.

The Health Trainer pathway developed with NHS Bolton was based on the existing national pathway. Participants were eligible for support over a period of six months. The average contact duration is 6 h. At the beginning of the intervention, participants developed a Personal Health Plan with their Health Trainer identifying which health behaviours put them at increased risk and outlining the changes they would like to achieve over the intervention period in order to reduce their risk. All appointments were recorded on both the general practitioner (GP) database and the Health Trainer database.

Data collection and analysis

Both projects used GP records to provide socio-demographic information (age, sex and ethnicity). Pre- and post-intervention clinical measurements were performed by clinical staff and included: 75 g oral glucose tolerance test (OGTT) performed to clinical standards,²² weight/body mass index (BMI) and pre-intervention FINDRISC (Finnish Diabetes Risk Score).²³ FINDRISC is a validated tool that assesses an individual's 10-year absolute risk of developing diabetes.

Both services used in-house databases to record data which were anonymized prior to analysis. Pre- and post-intervention changes in weight, BMI and plasma glucose were examined using paired t-tests. Statistical analysis was performed using StatSDirect.

Results

Salford telephone-based service

Table 1 shows the baseline characteristics of participants. The mean age was 65.3 years, 43.6% of participants were female and 8.1% were non-White. Their average weight was 90.0 kg, and they had a 2-h plasma glucose level of 9.1 mmol/l and a mean FINDRISC of 18.7.

Table 1.

Baseline characteristics of participants recruited to the lifestyle and behaviour change interventions.

Salford (N = 55)	Bolton (N = 83)
Age, mean (SD)	65.3 (12.6)	65.6 (11.8)
Sex, female (%)	43.6	41.0
Ethnicity, (%)
White	91.9	85.5
Asian	5.5	14.5
Black	1.8	0.0
Other	1.8	0.0
BMI (kg/m²), mean (SD)	32.4 (6.5)	31.0 (6.0)
Weight (kg), mean (SD)	90.0 (17.0)	87.0 (18.5)
Diabetes risk score, mean (SD)	18.7 (3.6)	17.8 (3.7)
OGTT score, mean (SD)	9.1 (0.9)	9.1 (0.9)

BMI: body mass index; OGTT: oral glucose tolerance test.

Following the intervention, mean weight loss was 3.3 kg (SD 4.3) and mean BMI reduced by 1.1 kg/m² (SD 1.5) (Table 2). These reductions were statistically significant (p < 0.001). 75% of participants lost weight and 28.8% achieved a weight loss of 5% body weight or more.

Fasting plasma glucose reduced by a mean of 0.3 mmol/l (SD 0.6) (p < 0.001) and 2-h plasma glucose by 1.6 mmol/l (SD 2.3) (p < 0.001). 47.3% of the participants achieved normal glucose levels but 9.1% developed diabetes. FINDRISC data show that the proportion of participants who reported daily fruit and vegetable consumption increased from 65.0% to 95.0% and the proportion reporting that they exercised for 30 min/day increased from 62.0% to 93.0%.

Bolton face-to-face service

The mean age was 65.6 years, 41.0% were female and 14.5% were non-White (Table 1). The average weight was 87.0 kg, mean 2-h plasma glucose level was 9.1 mmol/l and the mean FINDRISC score was 17.8.

After the intervention, the mean weight loss was 2.9 kg (SD 4.5), the BMI reduced by 1.1 kg/m² (SD 1.5) and waist circumference by 3.1 cm (SD 4.8) (Table 3). These reductions were statistically significant (p < 0.001). The percentage of participants who lost weight was 71.3%; 33.8% achieved a weight loss of 5% body weight or more. The mean 2-h plasma glucose level reduced by 0.7 mmol/l, though this was not statistically significant (Table 3). Normal glucose levels were achieved by 46.3% of participants and 8.5% had post-intervention 2-h plasma glucose in the diabetes range.

Table 2.

Changes in clinical and metabolic parameters among participants recruited to the Salford telephone intervention.

Baseline (N = 55)	After lifestyle intervention (six months) (N = 55)	Difference	p
BMI (kg/m²), mean (SD)	32.4 (6.5)	31.0 (5.8); n = 52	−1.1 (1.5)	<0.001
Weight (kg), mean (SD)	90.0 (17.0)	86.7 (15.7); n = 52	−3.3 (4.3)	<0.001
Waist circumference (cm), mean (SD)*	–	–	–	–
Fasting plasma glucose (mmol/l) (±SD)	6.1 (0.5)	5.9 (0.6); n = 52	−0.3 (0.6)	<0.001
OGTT 2-h plasma glucose (mmol/l) (±SD)	9.1 (0.9)	7.5 (2.5)	−1.6 (2.3)	<0.001

Waist circumference results were not collected for the telephone-based service.

BMI: body mass index; OGTT: oral glucose tolerance test.

Table 3.

Changes in clinical and metabolic parameters among participants recruited to the Bolton face-to-face intervention.

Baseline (N = 83)	After lifestyle intervention (six months) (N = 83)	Difference	p
BMI (kg/m²): mean (SD)	31.0 (6.0)	29.7 (5.5); n = 80	−1.1 (1.5)	<0.001
Weight (kg): mean (SD)	87.0 (18.5)	84.0 (17.0); n = 80	−2.9 (4.5)	<0.001
Waist circumference (cm): mean (SD)	105.3 (13.2); n = 65	102.2 (12.4); n = 65	−3.1 (4.8)	<0.001
Fasting plasma glucose (mmol/l) (±SD)*	–	–	–	–
OGTT 2-h plasma glucose (mmol/l) (±SD)	9.1 (0.9)	8.4 (3.2)	−0.7 (3.2)	0.058

Fasting results were not collected for the face-to-face service.

BMI: body mass index; OGTT: oral glucose tolerance test.

FINDRISC data show that the proportion of participants who reported daily fruit and vegetable consumption increased from 67.5% to 83.1% and the proportion of participants reporting that they exercised for 30 min/day rose from 41.0% to 72.3%.

Comparing the interventions

Baseline data show similarities between the samples of participants (Table 1). Both services demonstrated similar reductions in weight and BMI. The reduction of 2-h plasma glucose was statistically significant with the telephone-based service but not with the face-to-face service (Tables 2 and 3).

Implementation

The projects illustrate that it is possible to identify people with impaired glucose tolerance in primary care and to implement a lifestyle and behaviour change service, resulting in improvements in glucose tolerance and weight/BMI. Both services were well received by participants and general practices.

Both projects faced similar difficulties in recruiting people from NHS records even though we involved key stakeholders from initial project conception and took opportunities to promote the services with relevant health care professionals. Maintaining a register and annual recall system for patients with impaired glucose tolerance has been recommended.²⁴

We observed that general practices in Bolton did not remove the impaired glucose tolerance code from patients who revert to normal levels. This is to allow for future monitoring every three years ensuring people at risk of developing diabetes are monitored on a regular basis. This made the identification of eligible participants more difficult.

Discussion

Both localities now offer effective and easily accessible lifestyle services targeted at people at risk of diabetes. The costs of the two interventions were similar. However, both have potential advantages and disadvantages. A telephone-based service offers a more individualized and tailored approach which might be more suitable for populations in rural areas, for those who are housebound or for those with busy lifestyles. In contrast, a face-to-face service may speed up the relationship and trust building between participants and Health Trainers, with the additional opportunity to observe and interpret body language. Both services offer support on a one-to-one basis, which faces certain limitations compared to offering diabetes prevention in group settings, such as the lack of peer support and higher cost. However, both services offer the opportunity not only for targeted diabetes prevention education but also tailored support, enabling each participant to set appropriate lifestyle change goals.

Due to the fact these projects aimed to implement previous research findings rather than undertake new research, outcome measures followed local procedures rather than a research protocol. Another limitation was the lack of a control group who did not receive a lifestyle intervention, without which it is not possible to demonstrate that the interventions caused the improvements seen. However, our findings are in keeping with at least one large cohort study.⁸

After a diagnosis of impaired glucose tolerance, some patients will spontaneously return to normal glycaemic levels without any lifestyle or pharmacological intervention, due to natural body fluctuation or, maybe, changes they initiate themselves. However, this project suggests that Care-Call and Health Trainers can contribute to health improvements. Both offer practical and reproducible services that can be adapted and tailored to fit localities and target populations. The effect might diminish over time, so we are currently following up all participants one year after completion. We recommend that offering proactive, additional support to general practices in identifying people with impaired glucose tolerance should form part of any implementation strategy to ensure the successful uptake of the service.

Footnotes

Acknowledgements

We would like to thank both Primary Care Trusts; Salford's Diabetes team and Diabetes Commissioning Strategy Group; Lesley Hardman, Lynda Helsby and Dr Liversedge at NHS Bolton; and the Health Advisers, Health Trainers and participating general practices.

Conflict of interest

None of the authors have declared any conflict of interest.

Funding

The CLAHRC for Greater Manchester is funded by the National Institute for Health Research (NIHR) and NHS trusts in Greater Manchester. The views expressed are those of the authors and do not necessarily reflect those of the NHS Trusts or the NIHR.

References

Yorkshire and Humber Health Observatory. YPHO diabetes prevalence model: key findings for England, York: Yorkshire and Humber Health Observatory, 2010

Mozaffarian

Kamineni

Carnethon

. Lifestyle risk factors and new-onset diabetes mellitus in older adults: the cardiovascular health study. Arch Intern Med 2009; 169: 798–807

Alberti

. The clinical implications of impaired glucose tolerance. Diabet Med 1996; 13: 927–937

Edelstein

Knowler

Bain

. Predictors of progression from impaired glucose tolerance to NIDDM. An analysis of six prospective studies. Diabetes 1997; 46: 701–710

Lee

Saver

Hong

. Effect of pre-diabetes on future risk of stroke: meta analysis. BMJ 2012; 344: e3564–e3564

Eriksson

Lindgarde

. Prevention of type 2 diabetes (non-insulin dependent) diabetes mellitus by diet and physical exercise. The 6-year Malmo feasibility study. Diabetologia 1991; 34: 891–898

Ramachandran

Snehalatha

Mary

. The Indian Diabetes Prevention Programme shows that lifestyle modification and metformin prevent type 2 diabetes in Asian Indian subjects with impaired glucose tolerance (IDPP-1). Diabetologia 2006; 29: 289–297

Tuomilehto

Lindström

Eriksson

. Prevention of type 2 diabetes mellitus by changes in lifestyle among subjects with impaired glucose tolerance. N Engl J Med 2001; 344: 1343–1350

Diabetes Prevention Program Research Group. 10-year follow-up of diabetes incidence and weight loss in the Diabetes Prevention Program Outcomes Study. Lancet 2009; 374: 1677–1686

10.

Færch

Borch-Johnsen

Holst

. Pathophysiology and aetiology of impaired fasting glycaemia and impaired glucose tolerance: does it matter for prevention and treatment of type 2 diabetes? Diabetologia 2009; 52: 1714–1723

11.

Segal

Dalton

Richardson

. Cost-effectiveness of the primary prevention of non-insulin dependent diabetes mellitus. Health Promot Int 1998; 13: 197–209

12.

Hernan

Brandle

Zhang

. Costs associated with the primary prevention of type 2 diabetes mellitus in the diabetes prevention program. Diabetes Care 2003; 26: 36–47

13.

Yates

Davies

Gorely

. Effectiveness of a pragmatic education programme aimed at promoting walking activity in individuals with impaired glucose tolerance: a randomized controlled trial. Diabetes Care 2009; 32: 1404–1410

14.

Yates

Davies

Sehmi

. The Prediabetes Risk Education and Physical Activity Recommendation and Encouragement (PREPARE) programme study: are improvements in glucose regulation sustained at 2 years? Diabet Med 2011; 28: 1268–1271

15.

Paulweber

Valensi

Lindström

. A European evidence-based guideline for the prevention of type 2 diabetes. Horm Metab Res 2010; 42: S3–S36

16.

Schwarz

PEH

. Public health implications: translation into diabetes prevention initiatives – four-level public health concept. Med Clin North Am 2010; 95: 397–407

17.

Harvey

Fitzgerald

Fielden

. The NIHR collaboration for leadership in applied health research and care (CLAHRC) for Greater Manchester: combining empirical, theoretical and experiential evidence to design and evaluate a large-scale implementation strategy. Implement Sci 2011; 6: 96–96

18.

Young

Taylor

Friede

. Pro-active call centre treatment support (PACCTS) to improve glucose control in type 2 diabetes. A randomised controlled trial. Diabetes Care 2005; 28: 278–282

19.

Department of Health. Choosing health: making healthier choices easier, London: Department of Health, 2004

20.

Michie

Ashford

Sniehotta

. A refined taxonomy of behaviour change techniques to help people change their physical activity and healthy eating behaviours – the CALO-RE taxonomy. Psychol Health 2011; 26: 1479–1498

21.

Department of Health. Improving health: changing behaviour – NHS health trainer handbook, London: Department of Health, 2008

22.

World Health Organization. Definition, diagnosis and classification of diabetes mellitus and its complications, Geneva, Switzerland: Department of Noncommunicable Disease Surveillance, 1999

23.

Lindström

Tuomilehto

. The diabetes risk score. Diabetes Care 2003; 26: 725–731

24.

National Institute for Health and Clinical Excellence. Preventing type 2 diabetes: risk identification and interventions for individuals at high risk. NICE public health guidance 38, Manchester: National Institute for Health and Clinical Excellence, 2012