GPs fear PCT cuts will hurt service
Dr Azhar Farooqi explains how his practice introduced rapid diabetes screening for early detection
My practice of 13,000 patients in Leicester has an ethnic minority prevalence of 25 per cent, mostly south Asian. Diabetes is a particular issue as south Asians are at four times greater risk compared with Caucasians. Other ethnic groups, the elderly, the obese and those with a family history are also at high risk.
Early detection is important as by the time type 2 diabetes is discovered many patients already have complications.
Deciding who to screen
We decided the population at most risk was:
•Adults with a family history of diabetes
•Those with cardiovascular disease (diabetes greatly compounds their overall risk)
•Those with a past history of gestational diabetes.
It can be argued that for ethnic groups a lower age than 40 should be used as a threshold for screening, but there is no evidence-based guidance and workload considerations prevented us doing this.
There are several tests that can be used for screening, including urinalysis, random glucose, fasting glucose, HBA1C and the glucose tolerance test (GTT). The urinalysis and HBA1C tests are not sensitive enough for screening (urinalysis is also not specific).
GTT, the ‘gold standard', is expensive in time for the practice and the patient. Fasting or random glucose are practical first tests but a GTT is often needed for a definitive diagnosis (see box). We opted for fasting or random glucose as a practical way to initially screen a large number of patients.
1 Offer screening to over-40s (by posters and leaflets) involving a fasting or random glucose. Patients with a fasting level above 6mmol/l and a random one above 7mmol/l are invited for a GTT, unless the initial result and symptoms themselves are diagnostic.
2 Annual screening for patients on our CHD register (on attendance at the CHD clinic).
3 Annual invitations for those with a history of GTT.
The obese and those with a family history slot into category 1, but should probably have three-yearly invitations. We run specific clinic sessions for screening.
Screening is carried out predominately by health care assistants – but also practice nurses – who also do other cardiovascular risk checks as appropriate.
We run regular GTT sessions to cope with the numbers. The clinics are protocol driven with the nurse/ health care assistant arranging a GTT in patients with a high glucose on finger-prick testing.
The laboratory results are returned to doctors who interpret GTT results as well as deciding how to follow up and treat other abnormalities, such as abnormal lipids.
In the past two years we have screened 1,744 patients and detected 45 with diabetes (2.6 per cent) and 70 with impaired glucose tolerance (IGT) (4 per cent) or impaired fasting glucose (IFG). They now have annual recalls.
The service is resource intensive but very popular with patients who are increasingly aware of diabetes. The staff enjoy the work. The detection of IGT as well as diabetes and the opportunity to address other cardiovascular risk factors has made this work clinically and financially rewarding (in the context of QOF).
Two years ago we had about 450 patients with type 2 diabetes; we now have more than 600, with many detected by screening.
Azhar Farooqi is a GP in Leicester and an honorary senior lecturer at the University of Leicester Medical School
SCREENING FOR DIABETES
Fasting plasma glucose Two hours post 75g glucose load
Normal glucose homeostasis ?6.0mmol/l ?7.7mmol/l
Impaired fasting glucose 6.1-6.9 mmol/l Not applicable
Impaired glucose tolerance Not applicable 7.8-11mmol/l
Diabetes mellitus ?7.0mmol/l* ?11.1mmol/l */**
*On two occasions, or on a single occasion if symptoms (thrush, polyuria, weight loss) are present** Also random plasma glucose.