Diabetes guidelines: easier to preach than to practise?

Wendy Bryant,*, Jerry R Greenfield,*, Donald J Chisholm and Lesley V Campbell
Med J Aust 2006; 185 (6): 305-309. || doi: 10.5694/j.1326-5377.2006.tb00583.x
Published online: 18 September 2006


Objective: To review the management of glycaemia, blood pressure and serum lipids in a hospital outpatient diabetes clinic, the director of which co-authored the current national diabetes management guidelines.

Design: Retrospective audit.

Setting: Outpatient diabetes clinic in a tertiary referral teaching hospital, Sydney, NSW.

Study population: 96 patients with type 1 diabetes (mean age, 44.4 [SD, 12.8] years) and 509 patients with type 2 diabetes (mean age, 64.4 [SD, 12.0] years) attending the clinic in 2003, who had undergone formal review of complications.

Main outcome measures: Weight, height, control and treatment of glycaemia, blood pressure and serum lipids, and prevalence of diabetic microvascular complications.

Results: Glycated haemoglobin (HbA1c) was < 7% in 13% of type 1 and 30% of type 2 diabetes patients, and > 8% in 47% and 34%, respectively. 35% of patients with type 1 diabetes and 71% of patients with type 2 diabetes were treated with antihypertensive agents. Of these patients, 29% and 24%, respectively, had blood pressure readings ≤ 130/80 mmHg. Among patients not treated with hypertensive agents, blood pressure readings were ≤ 130/80 mmHg in 60% of type 1 and 38% of type 2 diabetes patients. About 30% of patients with type 1 diabetes and 50% of those with type 2 diabetes were being treated with lipid-lowering agents; of these, about 60% had low-density lipoprotein (LDL) cholesterol levels < 2.6 mmol/L. Among patients not treated with lipid-lowering agents, about 40% had LDL cholesterol levels < 2.6 mmol/L. Retinopathy was documented in 52% and 18%, and nephropathy in 9% and 36% of type 1 and type 2 diabetes patients, respectively.

Conclusions: Despite the demonstrated benefits of tight glucose, blood pressure and lipid control in reducing the risk of macrovascular and microvascular complications in type 1 and type 2 diabetes, our results suggest that treatment targets are not being met in a large proportion of patients attending a tertiary referral hospital. Responsible practice suggests that treatment targets and the current means to achieve them should both be examined.

The number of adults with diabetes worldwide is predicted to increase from 135 million in 1995 to 300 million in 2025.1 Diabetes is associated with a significantly increased risk of mortality, predominantly from cardiovascular disease.2 Intensive treatment of glycaemia, blood pressure and serum lipids has been shown to delay the onset and progression of complications in type 1 and type 2 diabetes.3-9 Similarly, intensive intervention targeting multiple risk factors reduces the risk of cardiovascular disease and microvascular complications both effectively and significantly in individuals with type 2 diabetes.10 Despite widespread reporting of these trial findings, their incorporation into clinical guidelines and subsequent implementation in routine practice is a challenge, with treatment targets sometimes unrealistic and difficult to meet.11 This is evidenced by a recent study of the management of type 2 diabetes in an urban Australian community, which reported that very few patients achieve recommended targets for glycaemic control.12

The aim of this audit was to review the outpatient management of glycaemia, blood pressure and lipids in a Sydney teaching hospital and to assess whether current treatment targets were being met. This is of particular interest as the director of the diabetes centre at this hospital (L V C) has co-authored diabetes management guidelines for general practitioners,13 and both senior authors (D J C and L V C) have published recommendations for diabetes management.14


Demographic and BMI characteristics of patients included in this audit are shown in Box 1.


Despite strong evidence that intensive control of cardiovascular risk factors reduces morbidity and mortality in type 1 and type 2 diabetes, our study of an outpatient diabetes clinic population revealed that a large number of patients were not achieving recommended treatment targets.

Over the past two decades, large, prospective, randomised studies have incontrovertibly demonstrated that intensive glycaemic control in patients with type 1 and type 2 diabetes delays the onset and progression of microvascular complications, such as retinopathy, nephropathy and neuropathy, and that glucose-lowering with metformin reduces the risk of macrovascular disease events in overweight patients with type 2 diabetes.3,5,6 Furthermore, in the Epidemiology of Diabetes Interventions and Complications (EDIC) Study, it was recently reported that, after 17 years of follow-up, participants with type 1 diabetes who previously had been treated intensively with insulin in the Diabetes Control and Complications Trial (DCCT) had a 42% lower risk of cardiovascular disease events compared with patients who previously had been treated conventionally.4 Given this strong evidence base, the ADA has recommended a target HbA1c of < 7%,15 and the new Joint British Societies’ guidelines (JBS 2) published in December 2005 recommended a target HbA1c of < 6.5%.16 As highlighted by our study and other studies reported in the literature,17-22 these targets are increasingly difficult to achieve (Box 2).

When interpreting our results, it is important to appreciate that HbA1c values in the clinic population described in this study are likely to be skewed to higher values, as the clinic population comprises mainly patients referred by general practitioners with poorly controlled or newly diagnosed type 1 and type 2 diabetes, or those recognised to have complications. Therefore, the study population represents a select group of patients, and our results may not be representative of patients with diabetes in the wider Australian community.

Our results should also be considered in the context of the findings of the United Kingdom Prospective Diabetes Study (UKPDS), in which median HbA1c values over 10 years were 7% in the intensively treated group.5 This result indicates that half of the intensively treated patients failed to achieve this glycaemic target, despite their participation in an intensive-treatment diabetes study. It is therefore not surprising (and perhaps even encouraging) that 30% of patients with type 2 diabetes in our clinic population had an HbA1c < 7%. It should also be noted that, although about half of the participants with type 1 diabetes in the intensive arm of the DCCT achieved an HbA1c ≤ 6.05% one or more times during the study, fewer than 5% of participants maintained an average value below this target, despite an intensive effort with full resources, expert staff and patient compliance.3 Nonetheless, our results illustrate that, with currently available therapies, many patients fail to reach recommended treatment targets. Indeed, clinicians appreciate that, for many patients, individualised recommendations may be more appropriate.23

The UKPDS also demonstrated that “tight” blood pressure control delayed the development and progression of macrovascular and microvascular disease in type 2 diabetes.7 It is important to note that, despite participation in a clinical trial, only 56% of patients in the “tight control” group and 37% in the “less tight control” group achieved a blood pressure < 150/85 mmHg. More recently, the Heart Outcomes Prevention Evaluation (HOPE) Study Investigators reported that patients with diabetes and at least one other cardiovascular risk factor (not necessarily hypertension) treated with the angiotensin-converting enzyme inhibitor ramipril were less likely to develop the composite endpoint of myocardial infarction, stroke or death from cardiovascular disease, compared with those who received placebo, despite a mean reduction in blood pressure of only 3/2 mmHg.24 Guidelines from the ADA published at the beginning of the year of our survey recommended that patients with diabetes receive anti-hypertensive medication(s) if blood pressure consistently equals or exceeds 140 mmHg systolic or 90 mmHg diastolic, with a treatment target of < 130/80 mmHg.15 This blood pressure target is consistent with recommendations from other expert societies from the United States,25,26 Australia13,27,28 and Europe.16,29-31 Despite this consensus, the current and previous studies17-22 demonstrate that many patients with diabetes do not achieve this treatment target in clinical practice (Box 2).

Primary and secondary prevention trials provide convincing evidence that lipid lowering reduces the risk of cardiovascular disease and death in people with diabetes.9 In 2003, the Heart Protection Study group reported that in 5963 patients with diabetes aged 40–80 years with non-fasting total cholesterol levels > 3.5 mmol/L (half of whom had no history of arterial disease at baseline), 40 mg/day of simvastatin significantly reduced coronary mortality and first non-fatal myocardial infarction.32 The average LDL cholesterol level in diabetic patients treated with simvastatin was ≤ 2.6 mmol/L. More recently, in a primary prevention study of 2838 participants with type 2 diabetes aged 40–75 years, 10 mg/day of atorvastatin led to a 37% reduction in the incidence of major cardiovascular events.33 In contrast, the Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) study recently reported mixed results regarding the effect of fenofibrate on cardiovascular disease events in type 2 diabetes.34

Consistent with the findings from these and other studies,8 the ADA has proposed that statins be commenced for primary prevention in patients with diabetes aged over 40 years if total cholesterol is ≥ 3.5 mmol/L, with an LDL cholesterol target of < 2.6 mmol/L.35 Although a similar target was published by the ADA in the year of our audit,15 our results indicate that only 60% of patients receiving lipid-lowering therapy and 40% of untreated patients had LDL cholesterol levels below this value. These recommendations are consistent with those proposed by other expert groups (Box 3),13,16,28,29,31,35-38 but conflict with Australian Pharmaceutical Benefits Scheme restrictions for the supply of subsidised drugs, which is probably a significant disincentive for the appropriate use of statins in diabetes management.

In conclusion, our survey of over 600 patients with diabetes indicates that there is significant discord between the evidence-based guideline targets formulated and advocated by physicians, and current treatment outcomes in our own clinical practice. Potential barriers to achieving recommended treatment targets include:11,39,40

Modification of restrictions by regulatory bodies, the development of medication combinations to reduce polypharmacy, and greater engagement with patients regarding the potential individual benefits and expected adverse effects of medications used to treat glycaemia, blood pressure and lipids may help to modify risk factors in patients with diabetes. However, if resources remain restricted, there may be a need to reassess current treatment recommendations and to prioritise expenditure in order to achieve realistic treatment targets in the increasing number of patients diagnosed with diabetes.

2 Proportion of patients with diabetes achieving glycaemic and blood pressure targets in selected published surveys

Percentage with HbA1c < 7%

Blood pressure

Study and year



Target (mmHg)

Percentage achieving target

Current study (2003)

Type 1 diabetes Type 2 diabetes

Sydney teaching hospital

13% 30%

≤ 130/80

29% (treated); 60% (untreated) 24% (treated); 38% (untreated)

ANDIAB (2004)17

Patients with diabetes (98% adult)

Australian diabetes centres


< 130/80

32% (39% aged < 60 years; 25% aged > 60 years)

AusDiab (1999–2000)18

Type 2 diabetes

National population-based survey

78% (diet) 50% (OHA only) 24% (insulin)

< 140/90

32% (treated), 55% (untreated)

NHANES (1999–2000)19

Adults with diabetes

National population-based survey


< 130/80


New Mexico study (1999–2000)20

Adults with diabetes

Managed care organisation


< 130/80


National Diabetes Audit UK (2003–2004)21

All patients with diabetes

Health care sector audit

23% (56%)

< 135/75


Swedish study (2003)22

Type 2 diabetes

National diabetes register


< 130/80  ≤ 140/85

13% (10% of treated patients) 50% (43% of treated patients)

Target glycated haemoglobin (HbA1c): * ≤ 1% above upper limit of normal range. < 6.5% (≤ 7.5%). < 7.3%. ANDIAB = Australian National Diabetes Information Audit and Benchmarking. AusDiab = Australian Diabetes, Obesity and Lifestyle Study. NHANES = National Health and Nutrition Examination Survey. OHA = oral hypoglycaemic agents.

3 Recommended low-density lipoprotein (LDL) cholesterol treatment targets in patients with diabetes

Diabetic patients in whom drug (statin) treatment indicated

LDL treatment target

American Diabetes Association (2005)35

Patients > 40 years with total cholesterol ≥3.5 mmol/L (consider drug treatment in high-risk patients aged < 40 years)

< 2.6 mmol/L (< 1.8 mmol/L in those with established cardiovascular disease)

National Cholesterol Education Program (NCEP) Adult Treatment Panel III (2001, 2004)36,37

LDL cholesterol ≥ 3.4 mmol/L (optional for LDL cholesterol 2.6–3.3 mmol/L)

< 2.6 mmol/L (< 1.8 mmol/L in those with established cardiovascular disease)

Diabetes Australia Guideline Development Consortium (type 2 diabetes) (2004)13

LDL cholesterol > 2.5 mmol/L

≤ 2.5 mmol/L

National Heart Foundation of Australia and Cardiac Society of Australia and New Zealand (type 2 diabetes) (2005)38

LDL cholesterol > 2.5 mmol/L

< 2.5 mmol/L (< 2.0 mmol/L in high-risk patients with coronary heart disease)

The Practical Implementation Taskforce for the Prevention of Cardiovascular Disease (2004)28

Total cholesterol > 3.5 mmol/L

Not stated

Third Joint Task Force of European and other Societies on Cardiovascular Disease Prevention in Clinical Practice (2003)29

Total cholesterol ≥ 5 mmol/L or LDL cholesterol ≥ 3 mmol/L

< 2.5 mmol/L

Joint British Societies (2005)16

All patients ≥ 40 years; patients aged 18–39 years with associated risk factors*

< 2.0 mmol/L (or 30% reduction from baseline, whichever is lower absolute value)

British Hypertension Society (2004)31

Patients with hypertension and type 2 diabetes aged up to at least 80 years with total cholesterol ≥ 3.5 mmol/L

< 2.0 mmol/L (or 30% reduction from baseline, whichever is lower absolute value)

* At least one of the following: retinopathy (pre-proliferative, proliferative, maculopathy), nephropathy, glycated haemoglobin (HbA1c) > 9%, hypertension, total cholesterol ≥ 6 mmol/L, features of the metabolic syndrome, first-degree relative with premature cardiovascular disease.

Received 24 December 2005, accepted 8 June 2006

  • Wendy Bryant,*1
  • Jerry R Greenfield,*2,3
  • Donald J Chisholm2,3
  • Lesley V Campbell1,2,3

  • 1 * Wendy Bryant and Jerry Greenfield contributed equally to the writing of this manuscript.
  • 2 Department of Endocrinology, St Vincent's Hospital, Sydney, NSW.
  • 3 Diabetes and Obesity Research Program, Garvan Institute of Medical Research, Sydney, NSW.



We acknowledge the physicians and diabetes educators who completed complication review forms. We also thank the nursing staff in the Diabetes Outpatient Clinic for recording anthropometric measurements.

Competing interests:

None declared.

  • 1. King H, Aubert RE, Herman WH. Global burden of diabetes, 1995-2025: prevalence, numerical estimates, and projections. Diabetes Care 1998; 21: 1414-1431.
  • 2. Haffner SM, Lehto S, Ronnemaa T, et al. Mortality from coronary heart disease in subjects with type 2 diabetes and in nondiabetic subjects with and without prior myocardial infarction. N Engl J Med 1998; 339: 229-234.
  • 3. The Diabetes Control and Complications Trial Research Group. The effect of intensive treatment of diabetes on the development and progression of long-term complications in insulin-dependent diabetes. N Engl J Med 1993; 329: 977-986.
  • 4. The Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) Study Research Group. Intensive diabetes treatment and cardiovascular disease in patients with type 1 diabetes. N Engl J Med 2005; 353: 2643-2653.
  • 5. UK Prospective Diabetes Study Group. Intensive blood-glucose control with sulphonylureas or insulin compared with conventional treatment and risk of complications in patients with type 2 diabetes (UKPDS 33). Lancet 1998; 352: 837-853.
  • 6. UK Prospective Diabetes Study Group. Effect of intensive blood-glucose control with metformin on complications in overweight patients with type 2 diabetes (UKPDS 34). Lancet 1998; 352: 854-865.
  • 7. UK Prospective Diabetes Study Group. Tight blood pressure control and risk of macrovascular and microvascular complications in type 2 diabetes: UKPDS 38. BMJ 1998; 317: 703-713.
  • 8. Cholesterol Treatment Trialists’ (CTT) Collaborators. Efficacy and safety of cholesterol-lowering treatment: prospective meta-analysis of data from 90 056 participants in 14 randomised trials of statins. Lancet 2005; 366: 1267-1278.
  • 9. Costa J, Borges M, David C, et al. Efficacy of lipid-lowering drug treatment for diabetic and non-diabetic patients: meta-analysis of randomised controlled trials. BMJ 2006; 332: 1115-1124.
  • 10. Gaede P, Vedel P, Larsen N, et al. Multifactorial intervention and cardiovascular disease in patients with type 2 diabetes. N Engl J Med 2003; 348: 383-393.
  • 11. Greenfield JR, Chisholm DJ. Clinical trials and clinical practice — bridging the gaps in type 2 diabetes. An evidence-based approach to risk factor modification in type 2 diabetes. Aust N Z J Med 2000; 30: 483-491.
  • 12. Davis TME, Davis WA, Bruce DG. Glycaemic levels triggering intensification of therapy in type 2 diabetes in the community: the Fremantle Diabetes Study. Med J Aust 2006; 184: 325-328. <MJA full text>
  • 13. Diabetes Australia Guideline Development Consortium. National evidence based guidelines for management of type 2 diabetes mellitus, 2004. education_info/nebg.html (accessed Dec 2005).
  • 14. Chisholm DJ, Campbell LV. Oral agents in type 2 diabetes: where to now? Med J Aust 1999; 171: 64-65.
  • 15. American Diabetes Association. Standards of medical care for patients with diabetes mellitus. Diabetes Care 2003; 26 Suppl 1: S33-S50.
  • 16. British Cardiac Society; British Hypertension Society; Diabetes UK; HEART UK; Primary Care Cardiovascular Society; Stroke Association. JBS 2: Joint British Societies’ guidelines on prevention of cardiovascular disease in clinical practice. Heart 2005; 91 Suppl 5: v1-v52.
  • 17. Flack JR, Colagiuri S, for the National Association of Diabetes Centres. Final report of the Australian National Diabetes Information Audit and Benchmarking (ANDIAB) 2004. (accessed Aug 2006).
  • 18. Kemp TM, Barr ELM, Zimmet PZ, et al. Glucose, lipid, and blood pressure control in Australian adults with type 2 diabetes. Diabetes Care 2005; 28: 1490-1492.
  • 19. Saydah SH, Fradkin J, Cowie CC. Poor control of risk factors for vascular disease among adults with previously diagnosed diabetes. JAMA 2004; 291: 335-342.
  • 20. Beaton SJ, Nag SS, Gunter MJ, et al. Adequacy of glycemic, lipid, and blood pressure management for patients with diabetes in a managed care setting. Diabetes Care 2004; 27: 694-698.
  • 21. The National Clinic Audit Support Programme (NCASP). National Diabetes Audit. (accessed May 2006).
  • 22. Eliasson B, Cederholm J, Nilsson P, et al. The gap between guidelines and reality: type 2 diabetes in a national diabetes register 1996-2003. Diabet Med 2005; 22: 1420-1426.
  • 23. Winocour PH. Effective diabetes care: a need for realistic targets. BMJ 2002; 324: 1577-1580.
  • 24. The Heart Outcomes Prevention Evaluation Study Investigators. Effects of an angiotensin-converting-enzyme inhibitor, ramipril, on cardiovascular events in high-risk patients. N Engl J Med 2000; 342: 145-153.
  • 25. Chobanian AV, Bakris GL, Black HB, et al. Seventh report of the Joint National Committee on prevention, detection, evaluation, and treatment of high blood pressure. Hypertension 2003; 42: 1206-1252.
  • 26. Chobanian AV, Bakris GL, Black HR, et al. The seventh report of the Joint National Committee on prevention, detection, evaluation, and treatment of high blood pressure: the JNC 7 report. JAMA 2003; 289: 2560-2572.
  • 27. National Heart Foundation. Hypertension management guide for doctors 2004. page=36 (accessed Mar 2005).
  • 28. The Practical Implementation Taskforce for the Prevention of Cardiovascular Disease. Prevention of cardiovascular disease: an evidence-based clinical aid 2004 [focus document]. Med J Aust 2004; 181: F1-F14. <MJA full text>
  • 29. De Backer G, Ambrosioni E, Borch-Johnsen K, et al. European guidelines on cardiovascular disease prevention in clinical practice. Third Joint Task Force of European and other Societies on Cardiovascular Disease Prevention in Clinical Practice (constituted by representatives of eight societies and by invited experts). Atherosclerosis 2004; 173: 381-391.
  • 30. Williams B, Poulter NR, Brown MJ, et al. Guidelines for management of hypertension: report of the fourth working party of the British Hypertension Society, 2004-BHS IV. J Hum Hypertens 2004; 18: 139-185.
  • 31. Williams B, Poulter NR, Brown MJ, et al. British Hypertension Society guidelines for hypertension management 2004 (BHS-IV): summary. BMJ 2004; 328: 634-640.
  • 32. Collins R, Armitage J, Parish S, et al. MRC/BHF Heart Protection Study of cholesterol-lowering with simvastatin in 5963 people with diabetes: a randomised placebo-controlled trial. Lancet 2003; 361: 2005-2016.
  • 33. Colhoun HM, Betteridge DJ, Durrington PN, et al. Primary prevention of cardiovascular disease with atorvastatin in type 2 diabetes in the Collaborative Atorvastatin Diabetes Study (CARDS): multicentre randomised placebo-controlled trial. Lancet 2004; 364: 685-696.
  • 34. Keech A, Simes RJ, Barter P, et al; FIELD study investigators. Effects of long-term fenofibrate therapy on cardiovascular events in 9795 people with type 2 diabetes mellitus (the FIELD study): randomised controlled trial. Lancet 2005; 366: 1849-1861.
  • 35. American Diabetes Association. Standards of medical care in diabetes. Diabetes Care 2005; 28 Suppl 1: S4-S36.
  • 36. Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults. Executive summary of the third report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). JAMA 2001; 285: 2486-2497.
  • 37. Grundy SM, Cleeman JI, Bairey Merz N, et al. Implications of recent clinical trials for the National Cholesterol Education Program Adult Treatment Panel III guidelines. Circulation 2004; 110: 227-239.
  • 38. Tonkin A, Barter B, Best J, et al. National Heart Foundation of Australia and the Cardiac Society of Australia and New Zealand: position statement on lipid management — 2005. Heart Lung Circ 2005; 14: 275-291.
  • 39. Greenhalgh T. Commentary: barriers to concordance with antidiabetic drugs — cultural differences or human nature? BMJ 2005; 330: 1250.
  • 40. Harris MI, Eastman RC, Cowie CC, et al. Racial and ethnic differences in glycemic control of adults with type 2 diabetes. Diabetes Care 1999; 22: 403-408.


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