General practitioners are at the core of diabetes care, risk factor modification and complication monitoring. When it comes to diabetes foot complications, the stakes are high and thus need to be carefully managed. The SingHealth Duke-NUS Diabetes Centre shares tips on primary care treatment and when referral to a specialist is needed.
THE DIABETES FOOT IN SINGAPORE
Prevalence
Lower limb amputations are one of the most feared
diabetes co mplications and unfortunately, Singapore has one of the highest amputation rates in the developed world1.
Diabetes mellitus affects approximately one in six
adults between 21 and 69 years of age in Singapore,
but the lifetime risk is projected to reach one in every
two adults by 2050.2
The lifetime risk of developing a foot ulcer ranges
from 15% to 25% of those with diabetes, while foot
ulcers precede 80% of all lower limb amputations
in those with diabetes.3
Risk factors
The risk factors for developing a foot ulcer and lower
limb amputation are well-established in Singapore.4
In addition to traditional cardiovascular risk factors
(e.g., dyslipidaemia, hypertension, smoking and poorly
controlled diabetes), a younger age at diagnosis
(longer duration of diabetes) and those with chronic
kidney disease are at the highest risk of diabetes foot
complications.
Diabetes foot problems make up a large proportion
of all hospital days due to diabetes, but integrated diabetes foot pathways with early access to care
can significantly reduce the morbidity associated
with diabetes foot disease.3
Patient background
Ms F is 53-year-old Malay ex-smoker working as a
store attendant. She was noted to have a painless
right foot callus during her regular review with her
general practitioner (GP). She has had type 2 diabetes for 12 years, complicated
by mild non-proliferative diabetic retinopathy
bilaterally, chronic kidney disease and peripheral
neuropathy noted on a diabetes foot screen four
years ago. She failed to attend regular diabetes foot screening
as she did not see its value. Symptoms
Ms F noticed a painless red discolouration around
a callus that had formed over the base of her right
foot under the first metatarsophalangeal (MTP) joint.
The callus was ascribed to her recent change in
footwear and had progressively darkened over the
preceding week.
She was pain-free and did not restrict her activities.
She did not wish to miss time at work, and thus only
consulted her primary care team six days later at her
scheduled chronic disease review.
Presentation
At presentation to her GP, there was a fluctuant
callus on the dorsal aspect of the first MTP on the
right. She had fallen arches bilaterally with poor nail
hygiene. She also had weak but palpable pulses bipedally,
and absent sensation up to the medial malleolus
bilaterally when assessed using a 10 g monofilament. The tissue surrounding the callus was erythematous
and warm, but she was apyrexic without signs of systemic infection or joint involvement. Clinical course
Ms F was treated with oral co-amoxiclav, advised to
avoid weight bearing on the foot and was referred to
the Rapid Access FooT (RAFT) Clinic at Singapore
General Hospital (SGH). Initial review and education
She was reviewed by the vascular, podiatry and
diabetes teams three days later. Vascular review Non-invasive vascular imaging was arranged on the
same day and a clinical assessment was performed. Podiatry review Local debridement and evacuation of a pus-filled
cavity under the callus, nail care and education (offloading,
dressing plan, nail care plan and footwear
guidance) was performed. Diabetes review Cardiovascular risk factors and glycaemic control
were addressed.
Her atheromatous changes were distal and there
was not any focal proximal arterial stenosis noted
on imaging to merit considering revascularisation
options. Some misconceptions about the role of regular
foot screening were addressed in addition to giving
guidance on wound care and dressings. Ms F and
her family were educated regarding appropriate
footwear, the red flags / warning signs to look out for
and what actions to take if concerned.
Follow-up review and recovery
Her employer allowed her to take sufficient time off
work to facilitate wound healing and she was also
able to perform her duties while seated when she
returned to work. Her wound healed well after five weeks with regular
podiatry review and wound dressings.
Her statin therapy was changed to a more potent
statin to achieve an LDL under 1.8 mmol/L, and she
commenced a sodium-glucose cotransporter-2 inhibitor
(SGLT2i) after her wound healed to address
her CKD with microalbuminuria, raised BMI and
suboptimal glycaemic control. Her LDL and HbA1c had both improved three
months later when reviewed by her primary care
team. She was advised that while her wound was
‘healed’, the recurrence rate within one to five years
is extraordinarily high, and she will remain in the
highest risk group for developing a future foot ulcer. |
TREATMENT OPTIONS BY GPs
The key initial approach is to:
- Offload the foot
- Treat any underlying infection
- Consider local treatments to accelerate healing
- Escalate care if necessary
GPs can consult the Appropriate Care Guide5 by the Agency for Care Effectiveness when assessing an individual's risk of diabetes foot complications.
Table 2 outlines the various assessment and treatment options available.
An experienced wound nurse and podiatrist are invaluable when considering local treatments and choosing the most appropriate dressings and footwear for acute diabetes foot injuries.
Often, patients presenting with an acute foot ulcer have been infrequent attenders to the clinic. Many have poorly controlled cardiovascular risk factors or have missed screening for other diabetes complications, and this represents an opportunity to re-engage the patient.
Initial assessment
and reassessment | - Look for risk factors, evidence of infection, arterial insufficiency, neuropathy, pedal oedema and bony deformities
- Footwear assessment
- Wound assessment: depth, surrounding tissue, exudate, evidence of gangrene
- Assessment for ischaemia
|
Local treatments | - Debridement and treatment of the callus
- Wound culture prior to broad spectrum antimicrobials
|
Infection treatment | - Targeted therapy based on wound culture rather than superficial swab
- Empiric antimicrobial in the absence of tissue culture
|
Education | - Wound care
- Nail and foot care
- Red flags and emergency contacts
|
Offload | - Footwear (insole/orthotics)
- Avoid walking or other weight-bearing activities
|
Revascularisation / Surgery | - Endovascular options
- Bypass procedures
- Deformity correction (e.g., hammertoe, bunion)
- Amputation
|
Opportunistic diabetes complications and cardiovascular risk factor screening |
WHEN GPs SHOULD
REFER A PATIENT
Referral to the emergency department
Signs or symptoms of acutely ischaemic foot or evidence of systemic infection due to a foot infection should prompt immediate referral to the emergency department.
Referral to a diabetes foot specialist
A new ulcer, any tissue loss or foot infection in patients at higher risk should prompt early review by a diabetes foot specialist.
Even those at lower risk with wounds that worsen at any stage of treatment or fail to improve after four weeks of initial therapy should also be referred.
Those with intermittent claudication or rest pain should be seen early by a vascular surgeon.
Absent or reduced pulses and lower ankle brachial index (ABI) scores without tissue loss are common findings. If these are noted in those without symptoms or tissue loss, invariably, early specialist review is unnecessary.
Rapid access clinics
There is an array of rapid access clinics available with the appropriate option dependent on the physician’s level of concern and the primary complaint.
In SGH, patients like Ms F can be referred to the:
Rapid Access FooT (RAFT) Clinic
Rapid Access Vascular Clinic
Diabetes Fast Track Clinic
Similar services are available in Sengkang Hospital and Changi General Hospital.
TREATMENT OPTIONS BY SPECIALISTS
The main advantage of a dedicated diabetes foot clinic is the coordination of investigations and care with multidisciplinary input on treatment decisions.
These clinics reduce the number of hospital visits for patients and have repeatedly been shown to reduce the morbidity associated with diabetes foot disease.3
Revascularisation, skin grafting and foot deformity corrective surgery are some of the surgical options available in addition to surgical debridement, and major or minor lower extremity amputation.
REASSESSMENT AND FOLLOW-UP
Continued monitoring and timely referrals
Diabetes care, risk factor modification and complication monitoring should be centred in primary care for the majority of patients.
Those with a history of foot ulcers will remain at high risk of recurrence. Therefore, four-to-six-monthly foot assessments augmenting the patients’ and carers’ daily examination of the patients’ feet are necessary.
Rapid access to a multidisciplinary team assessment when necessary can reduce the need for lower extremity amputations.
Improving patient education
Each touchpoint in clinics and hospitals is an opportunity to improve patient knowledge. We have demonstrated that a collaborative approach in patient education can yield a greater increase in knowledge retention and self-care behaviours.6
Giving patients the tools to recognise diabetes foot problems and the appropriate actions to take are key factors in reducing morbidity in Singapore.
Lower health literacy in older patients, challenges around missing work and fear of amputations are some of the common reasons observed for delayed presentation with an acute diabetes foot problem in Singapore. This can be minimised through coordinated care, regular screening and targeted education.
REFERENCES
Riandini T, Pang D, Toh MPHS, Tan CS, Choong AMTL, Lo ZJ, Chandrasekar S, Tai ES, Tan KB, Venkataraman K. National Rates of Lower Extremity
Amputation in People With and Without Diabetes in a Multi-Ethnic Asian Population: a Ten Year Study in Singapore. Eur J Vasc Endovasc Surg.
2022 Jan;63(1):147-155. doi: 10.1016/j.ejvs.2021.09.041. Epub 2021 Dec 14. PMID: 34916107.
Phan TP, Alkema L, Tai ES, et al. Forecasting the burden of type 2 diabetes in Singapore using a demographic epidemiological model of Singapore.
BMJ Open Diabetes Research and Care 2014;2:e000012. doi: 10.1136/bmjdrc-2013-000012
Armstrong DG, Boulton AJM, Bus SA. Diabetic Foot Ulcers and Their Recurrence. N Engl J Med. 2017 Jun 15;376(24):2367-2375. doi: 10.1056/NEJMra1615439. PMID: 28614678.
Yang Y, Østbye T, Tan SB, Abdul Salam ZH, Ong BC, Yang KS. Risk factors for lower extremity amputation among patients with diabetes in
Singapore. J Diabetes Complications. 2011 Nov-Dec;25(6):382-6. doi: 10.1016/j.jdiacomp.2011.08.002. Epub 2011 Oct 7. PMID: 21983153.
Agency for Care Effectiveness. Foot assessment in people with diabetes mellitus. Retrieved 28 November 2022, from https://www.ace-hta.gov.sg/healthcare-professionals/ace-clinical-guidances-(acgs)/details/foot-assessment-in-people-with-diabetes-mellitus
Heng ML, Kwan YH, Ilya N, Ishak IA, Jin PH, Hogan D, Carmody D. A collaborative approach in patient education for diabetes foot and wound care: A pragmatic randomised controlled trial. Int Wound J. 2020 Dec;17(6):1678-1686. doi: 10.1111/iwj.13450. Epub 2020 Jul 29. PMID: 32729231; PMCID: PMC7949298.
Ng N. Understanding Diabetes and chronic limb-threatening ischaemia. SingHealth Defining Med. Retrieved 28 November 2022, from https://www.singhealth.com.sg/news/defining-med/chronic-limb-threatening-ischaemia
Dr David Carmody is an Endocrinologist based at Singapore General Hospital. He is the
lead endocrinologist in the hospital’s Rapid Access FooT clinic.
Dr Carmody graduated with an MB BCh BAO (Honours) from the Royal College of Surgeons
in Ireland (RCSI) in 2004. He completed his advanced specialist training in both internal
medicine and endocrinology through the Royal College of Physicians in Ireland in 2016. He was awarded his postgraduate research degree (MD) in 2017 by RCSI.
His current clinical and research interests focus primarily on atypical forms of diabetes mellitus and complications of diabetes mellitus.
GPs can call the SingHealth Duke-NUS Diabetes Centre for appointments at the following hotlines:
Singapore General Hospital: 6326 6060
Changi General Hospital: 6788 3003
Sengkang General Hospital: 6930 6000
KK Women's and Children's Hospital: 6692 2984
Singapore National Eye Centre: 6322 9399