Managing diabetes in primary care
Pearl Toh spoke with Dr Teh Ming Ming, senior consultant at the Department of Endocrinology, Singapore General Hospital (SGH), on the major challenges of diagnosing and managing diabetes in primary care, in conjunction with the World Diabetes Day on 14 November. Awareness of the symptoms of diabetes is important, and patients should be empowered to manage their conditions.
Diabetes is the 3rd most common condition attended by GPs in Singapore polyclinics. The National Health Survey 2010 showed that 11.3 per cent of residents in Singapore aged 18–69 years have diabetes.
More recent figure in 2014 showed that about 440,000 residents in Singapore aged ≥18 years have diabetes. Vast majority of these cases are type 2 diabetes (T2D). However, many patients are unaware that they actually have diabetes, necessitating efforts to raise awareness on the symptoms and implications of undiagnosed diabetes.
Some of the key symptoms of diabetes include frequent urination, excessive thirst, extreme fatigue, blurred vision, and slow healing wounds. Missed opportunity of detecting diabetes early may lead to complications involving target organ damage such as retinopathy, nephropathy, and neuropathy.
Diabetes can be diagnosed when any one of the following conditions is present: random plasma glucose of ≥11.1 mmol/L, fasting plasma glucose of ≥7 mmol/L, or plasma glucose of ≥11.1 mmol/L in the 2-hour oral glucose tolerance test. In the event of disagreement between the different diagnostic tests, testing can be repeated.
A major challenge in diagnosing diabetes is the lack of knowledge on diabetes symptoms at the patient level, which could lead to them not seeking medical help earlier and hence, underdiagnosis of the disease.
GPs should be vigilant of the risk factors of diabetes ─ such as obesity, hypertension, and hyperlipidaemia ─ and encourage patients with these risk factors to go for diabetes screening. This can facilitate early detection of diabetes in patients who are unaware of their condition. For some, lifestyle modifications may even alter the course of diabetes, especially during the early phase of the disease.
The key aims of diabetes management are to control blood glucose levels to within the normal range and to minimize the risk of developing diabetes complications. GPs can achieve this goal through appropriate use of diabetes pharmacotherapy and empowering the patients with knowledge of diabetes management.
Metformin is the starting point for most T2D patients if there is no obvious contraindication. Dual therapy with the addition of sulphonylureas, dipeptidyl peptidase-4 inhibitors, thiazolidinediones, sodium-glucose cotransporter-2 inhibitors, glucagon-like peptide 1 receptor agonists, or basal insulin can be considered if glycaemic control remains suboptimum. Triple therapy can be considered if dual therapy fails to achieve the optimum glycaemic control.
GPs should consider referring T2D patients to a specialist if triple therapy or combination injectable therapy is being considered. Nonetheless, this depends largely on how comfortable are the GPs in managing complex diabetes regimens. On the other hand, GPs should consider referring all type 1 diabetes (T1D) patients to a specialist.
For reference, GPs can consult the Ministry of Health Clinical Practice Guidelines. [Singapore Med J 2014;55:334-347]
Major challenge ─ hypoglycaemia
One major challenge in diabetes treatment lies in striking the right balance between achieving the optimum blood glucose control and minimizing the risk of hypoglycaemia. Hypoglycaemia occurs when blood glucose level falls to <4 mmol/L. Typical signs and symptoms of hypoglycaemia include tremor, excessive sweating, dizziness, palpitation, and double vision, among others.
It is important to educate diabetes patients about the symptoms and implications of hypoglycaemia and to ask for the occurrence of hypoglycaemia at every clinic consultation. When blood glucose drops to a very low level, the higher executive functions of the brain will be severely compromised, which will pose hazards when performing complex task such as driving or operating a machine.
Another important implication relates to self-treatment of hypoglycaemia ─ the brain is no longer able to make sensible decision on managing hypoglycaemia if the blood glucose drops to a critically low level. In the case of severe hypoglycaemia ─ which occurs when the patients need help from others in treating their low blood glucose levels ─ this can result in loss of consciousness, seizure or even death if not intervened in time.
Particularly, older patients are at a higher risk of severe hypoglycaemia. This can be potentially devastating as many older patients may be living alone or spending most part of the day alone. The resulting loss of consciousness can lead to fall with fractures or significant head injury.
Therefore, empowering patients with the basic knowledge of diabetes and hypoglycaemia management will complement the efforts of GPs in optimizing diabetes control.
What patients can do in managing hypoglycaemia
To avoid hypoglycaemia, patients should follow a regular meal pattern and regularly monitor their blood glucose levels for those on insulin treatment. Most patients can self-treat hypoglycaemia by ingestion of carbohydrate or glucose before their blood glucose drops to a critical level.
They should also avoid unaccustomed exercise. If the frequency and intensity of exercise is increased, care must be taken by checking blood glucose levels before, during, and after the exercise such that adjustments of diabetes medications or carbohydrate intake can be made when necessary.
What GPs can do in managing hypoglycaemia
Actively looking out for patients with problematic hypoglycaemia is a good move to improve diabetes care. There are some clinical tools which have been developed to pick up patients with problematic hypoglycaemia. One of the user-friendly clinical tools is the Gold questionnaire, which takes less than 10 seconds for the patient to complete. A score of ≥4 may indicate problematic hypoglycaemia.
The questionnaire is aimed at picking up diabetes patients who have a reduced ability to detect hypoglycaemia due to diminished symptomatic responses to hypoglycaemia, termed impaired awareness of hypoglycaemia (IAH). IAH is a significant risk factor for severe hypoglycaemia.
Patients who are at high risk of IAH include: (i) T1D patients with tight glycaemic control and long duration of diabetes, and (ii) T2D patients with tight glycaemic control.
Pharmacotherapy is only one part of diabetes treatment. Empowering diabetes patients with the necessary knowledge and skill in managing diabetes constitutes another important part of diabetes care. Therefore, GPs should engage their patients in diabetes care.