Introduction

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Type 2 diabetes is a serious condition, with implications for the mortality, morbidity, and social functioning of patients. The prevalence of type 2 diabetes is increasing, and the number of patients in the United Kingdom is expected to rise from just over one million in 1997 to just under three million by 2010.¹ An estimated 7-8% of the total NHS budget is spent on patients with type 2 diabetes,² and the burden of caring for these patients is falling increasingly on primary care. ^{3 4}

Impaired glucose tolerance, typically characterised by hyperglycaemia and insulin resistance, is considered to be a stage in the development of type 2 diabetes. Up to half of all people with impaired glucose tolerance will progress to type 2 diabetes within 10 years of diagnosis.⁵ In addition, people with impaired glucose tolerance are known to be at significantly increased risk of cardiovascular disease, which may present before the onset of diabetes.⁶ Studies in the United Kingdom have reported the prevalence of impaired glucose tolerance in the 35-65 year age group to be around 17%.⁷

Increasing evidence indicates that intervention can favourably influence the clinical course of impaired glucose tolerance,^8-10 with some studies showing a 58% reduction in progression to diabetes. ^{11 12} This study aimed to ascertain levels of awareness among general practitioners of the prevalence and clinical significance of impaired glucose tolerance and to explore their attitudes to its detection and management.

	Methods

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Participants and setting
Focus groupsWe chose general practitioners from lists supplied by Derwentside, Sunderland West, South Tyneside, and Gateshead West and Central Primary Care Groups. We contacted 56 general practitioners. Twenty six general practitioners (18 men, eight women) participated in four focus groups. The mean age of participants was 44 (range 30-58) years; all were principals, with a mean of 11 (1-27) years' experience in general practice (see also bmj.com). The 30 general practitioners who either declined or failed to attend were similar in terms of sex and practice characteristics.

Semistructured interviewsWe chose the eight participants (six men, two women) in the semistructured interviews purposively¹³ from a list of all general practitioners in one health authority. All were principals, with a mean age of 41 (31-46) years and an average of 12 (4-24) years' experience in general practice.

Collection and analysis of data
The lead investigator (GW) carried out all the focus groups and interviews, which were audiotaped for later transcription. Before each focus group, participants completed a questionnaire designed to evaluate their knowledge of the clinical significance and prevalence of impaired glucose tolerance. Their responses were then explored in the focus group discussion. The lead investigator then gave a short presentation, based on a review of the literature, on the anticipated rise in prevalence of type 2 diabetes, together with the clinical significance, prevalence, and management of impaired glucose tolerance. ^{1 2 5-11} Further focus group discussion centred around participants' attitudes to impaired glucose tolerance in the light of what, for most of them, was new knowledge.

We took a similar approach with the semistructured interviews, administering the questionnaire verbally and following this with open ended questions concerning knowledge of the clinical significance and prevalence of impaired glucose tolerance. We then gave a short presentation, as above, and used subsequent open ended questions to explore attitudes to and perceptions of the detection and management of impaired glucose tolerance.

We used a "pragmatic variant" grounded theory approach to analyse the data by generating categories and themes. ^{14 15} GW and APSH coded the data independently to increase the reliability of the study. We adopted an iterative approach to data analysis, with analysis beginning after the first focus groups and interviews, to allow emerging themes to be explored in subsequent interviews. The coders agreed that no new themes were emerging after four focus groups and eight semistructured interviews, and saturation was achieved.¹⁵

Validation
To increase confidence in the validity of the findings, we sent all 34 participants a report summarising the outcomes of the study. Twenty eight (82%) replied stating that they "strongly agreed" (10 respondents) or "agreed" (18) that the report was a true representation of their opinions.

	Results

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QuestionnairesAll participants were aware of impaired glucose tolerance as a clinical entity. However, 16 (47%) participants were unaware of the risk of impaired glucose tolerance progressing to type 2 diabetes, and 21 (62%) were unaware of the increased risk of cardiovascular disease. In addition, 17 (50%) participants had no idea how many patients with impaired glucose tolerance might be known to their practice, and 13 (38%) estimated prevalence at less than 1%.

Focus groups and interviewsThree main themes emerged from data collected before participants received a presentation detailing the anticipated rise in prevalence of type 2 diabetes, together with the clinical significance, prevalence, and management of impaired glucose tolerance (box 1). Eight main themes emerged after the presentation (box 2).

	Discussion

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The recently published Diabetes National Service Framework: Standards document recommends that the NHS and partner organisations adopt both a "population" approach (tackling obesity and sedentary lifestyles) and a "targeted" approach (identifying and intervening in high risk groups, such as patients with impaired glucose tolerance) to reducing the incidence of type 2 diabetes.¹⁶ The national service framework recognises that such interventions are also likely to have an impact on reducing cardiovascular disease. Similarly, early treatment of macrovascular risk factors may be more important than screening for and treating asymptomatic type 2 diabetes itself.¹⁷ Although studies from other countries have shown encouraging results, ^{11 12} questions about the feasibility of primary prevention of type 2 diabetes in the United Kingdom remain unanswered. Our findings clearly show that general practitioners have major reservations about the appropriateness and effectiveness of giving lifestyle advice to patients in this context. Similarly, we have shown that general practitioners perceive the need for considerable extra resources if they are to be given the task of screening for impaired glucose tolerance and intervening in patients at high risk of progression to type 2 diabetes. This has important implications, both for the implementation of the diabetes national service framework and for primary care research.

General practitioners' awareness of the existence of impaired glucose tolerance was good, but awareness of the prevalence and clinical significance of impaired glucose tolerance was poor. In addition, general practitioners seem to be uncertain about how best to manage and follow up these patients. This has implications for the training and education of general practitioners, and not least for patient care in a field that is likely to expand exponentially in the next few years.

	Acknowledgments

We thank the general practitioners who participated in the study and Brenda Hall, Glenys Ambrose, Jan Roach, and Jane Przborski for transcribing the tapes.

Contributors: See bmj.com

	Footnotes

Funding: Northern and Yorkshire Regional Health Authority, through a research training fellowship awarded to GW.

Competing interests: We received funding for hospitality for the focus groups from Pfizer Pharmaceuticals. The Centre for Integrated Health Care Research received an educational grant from GlaxoSmithKline Pharmaceuticals in 1997.]

The full version of this article appears on bmj.com

	References

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(Accepted 28 February 2002)