84
VOLUME 10 NUMBER 3 • SEPTEMBER 2013
RESEARCH ARTICLE
SA JOURNAL OF DIABETES & VASCULAR DISEASE
The tolerability and safety of DPP-4 inhibitors for the
treatment of older people with type 2 diabetes mellitus:
an observational study
Adie Viljoen,Claire L Meek, Roger Gadsby, Sumarie Viljoen,Haya Langerman, Alan J Sinclair
Correspondence to: Dr Adie Viljoen
Institute of Diabetes for Older People, University of
Bedford, Putteridge Bury Campus, Luton, and Department of Chemical
Pathology, Lister Hospital, Stevenope, UK
email:
Claire L Meek
Department of Chemical Pathology, Lister Hospital, Stevenope, UK
Roger Gadsby
Institute of Clinical Education, Medical School Building, University of
Norwick, UK. Institute of Diabetes for Older People, University of Bedford,
Putteridge Bury Campus, Luton, UK.
Sumarie Viljoen and Alan J Sinclair
Institute of Diabetes for Older People, University of Bedford, Putteridge
Bury Campus, Luton, UK.
Haya Langerman
Institute of Diabetes for Older People, University of Bedford, Putteridge
Bury Campus, Luton, UK.
Originally in:
Br J Diabetes Vasc Dis
2013;
13
(4): 187–191.
S Afr J Diabetes Vasc Dis
2013;
10
: 84–87
Abbreviations:
ADA
American Diabetes Association
EASD
European Association for the Study of Diabetes
DPP
dipeptidylpeptidase
eGFR
estimated glomerular filtration rate
GLP-1
glucagon like polypeptide
HbA
1c
glycated haemoglobin
NHS
National Health Service
MDRD
Modification of Diet in Renal Disease
NICE
National Institute for Health and Care Excellence
Abstract
Aims/introduction:
Despite type 2 diabetes mellitus being
up to five times more prevalent in patients aged ≥ 65 years
compared with patients < 65 years of age, this population is
surprisingly less well studied. Dipeptidyl peptidase (DPP)-4
inhibitor treatment is an option for this older patient group,
but clinical practice data for this drug class are sparse in this
population. The study examined the efficacy and tolerability
of DPP-4 inhibitors in older patients with type 2 diabetes
whilst focusing on particular pertinent aspects relevant to
care of older persons.
Materials and methods:
The medical records of 431 randomly
selected patients (median age 74 years) were reviewed and
two cohorts (DPP-4-inhibitor-treated and non-DPP-4-inhibitor-
treated) were compared.
Results:
Bothgroups had a similar durationof diabetes (8 years)
and comparable glycated haemoglobin A
1C
concentrations
(7.4% and 7.2%). Hypoglycaemia was less common in the
DPP-4 inhibitor group (3%) compared with the medically
treated non-DPP-4 inhibitor group (8%), p < 0.02. Despite
significantly more patients in the non-DPP-4 inhibitor group
living in cared accommodation (9 vs 2%) this group received
significantly more insulin (30 vs 7%)
Conclusion:
Clinicians need to consider the specific clinical
issues relevant to older diabetic patients when taking complex
treatment decisions.
Keywords:
diabetes in elderly, dipeptidylpeptidase, DPP-4
inhibitors, hypoglycaemia
Introduction
Diabetes is up to five times more prevalent in patients aged 65
years or older than in patients below the age of 65.
1
Indeed up to
one in five older people have diabetes and a similar proportion may
have undiagnosed diabetes.
2
It has been clearly demonstrated that
medical intervention which lowers blood glucose can lower the risk
of future complications, most notably, microvascular complications.
3
The side effects of glucose lowering treatments include weight gain
and hypoglycaemia with sulphonylureas and insulin, increased of
risk of fractures, congestive heart failure, weight gain and increased
risk of bladder cancer with pioglitazone and gastrointestinal
side effects related to acarbose and metformin. The newer drug
classes acting on the GLP-1 axis namely DPP-4 inhibitors (gliptins)
and GLP-1 analogues have had fewer years of post-marketing
surveillance and fewer patients taking these medications have been
studied in both clinical trials and in clinical practice compared with
insulin, metformin, sulphonylureas and pioglitazone. Their safety
with respect to their potential link to pancreatitis and pancreatic
cancer remains under scrutiny.
4
These medications do however have advantages in terms of
weight management, namely weight neutrality (DPP-4 inhibitors)
and weight reduction (GLP-1 analogues), and a lower risk of
hypoglycaemia when compared with insulin and sulphonylureas.
DPP-4 inhibitors can be taken orally whereas GLP-1 analogues
require injection. DPP-4 inhibitors are generally well tolerated
whereas GLP-1 analogues are associated with nausea and vomiting
(especially in the first few weeks of treatment) but DPP-4 inhibitors
are less efficacious in terms of HbA
1C
reduction than GLP-1
analogues.
As highlighted by the NICE guidelines for type 2 diabetes,
5
the risk of hypoglycaemia is of particular concern in the older
population. Older patients are at higher risk of hypoglycaemia,
whose symptoms may be mistaken for other conditions associated
more commonly with advanced age. In addition, older patients
often require more support with their diabetes management
than younger patients and more commonly suffer from other
