Download Tight Control Joel Jorgenson PGY-3 March 2015 Story from the

Tight Control
Joel Jorgenson PGY-3
March 2015
Story from the Front Lines: A woman in her 80s returned to clinic for management of
her chronic health issues. She has a history of stroke, congestive heart failure, atrial
fibrillation, coronary artery disease and Type 2 diabetes. She has been taking glyburide
and sitagliptin for her diabetes. She manages her own medications and lives
independently. She has had diabetes for many years and is very concerned about the risks
of hyperglycemia. Due to this concern she has restricted her diet and she carefully avoids
all sugary foods. She denies symptomatic hypoglycemia. Her HbA1c three months ago
was 6.5.
Teachable Moment: The 2011 American Diabetes Association Standards of Medical
Care recommends a goal hemoglobin A1c of less than 7% to reduce to microvascular and
neuropathic complications of diabetes.1 Two recent trials have addressed this question for
older patients with type 2 diabetes. ADVANCE randomized patients to standard care or
tight control with a goal A1c of less than 6.5. Primary outcomes were a composite of
microvascular and macrovascular complications. The study had a positive result in favor
of tight control but the results were driven by the decreased rate of nephropathy.2 The
second trial that addressed this question was ACCORD. The study compared a goal A1c
of less than 6 to 7-7.9. The study showed an increase in all cause mortality for patients in
the tight control group.3
Determining optimal therapeutic goals in the geriatric population is important due to the
high prevalence of Type 2 diabetes and the risks of hypoglycemia and polypharmacy. In
2012, 26.9 percent of United States residents 65 years or older had diabetes.4 Applying
current trial data to this population is troublesome because randomized trials focusing on
optimal glycemic targets have often excluded elderly patients. In a Cochrane Review
from 2011, only four of 20 trials included subjects with a mean age over 65 and only two
of those four studies enrolled more than 100 participants.5 The other problem with the
current guidelines is that many of these studies were performed in newly diagnosed
diabetics. For example, in UKPDS 34 patients had a mean age of 53 and the inclusion
criteria specified newly diagnosed diabetics who were followed for 10 years.3 This is
important because older diabetics are less likely to be newly diagnosed.6 Given that it
takes 10 years to realize a benefit from these intensive therapies, life expectancy needs to
be taken into account. Often these patients have numerous comorbidities with life
expectancy less than 10 years. These considerations call into question the benefits of tight
glucose control in this population which may be outweighed by the harms from
hypoglycemia.
Intensive control of blood sugars often requires multiple medications, many of which
carry significant risk of hypoglycemia. In ADVANCE 2.7% of patients in the intensive
care group experienced hypoglycemia requiring the aid of another person as opposed to
1.5% of the control group.2 While these rates are low in a middle aged population, the
elderly are at much higher risk. Observational studies suggest that increasing age and the
use of five or more medications are all independent risk factors for hypoglycemic
episodes for patients treated with insulin or sulfonylureas.8 The patient in this case was on
a sulfonylurea with a blood sugar with an hemoglobin A1c below the goal for a healthy
middle aged woman. Given that her life expectancy is under 10 years, the benefits of
tight control would be minimal and her risk of hypoglycemia is elevated due to her risk
factors. Adjusting her A1c goal based on this information seems appropriate. The
American Geriatric Society has released “Choosing Wisely” guidelines to help clinicians.
They stratify A1c goals based on life expectancy. If we assumed a 5-10 year life
expectancy for this patient, they recommend an A1c goal of 7.5-8.9
1. American Diabetes Association. Standards of Medical Care in Diabetes— 2011
[on-line]. Available at
http://care.diabetesjournals.org/content/34/Supplement_1/S11.full.pdf+html
Accessed November 14, 2011. 2. Harris R, Donahue K, Rathore SS et al.
2. Patel A, MacMahon S, Chalmers J et al., ADVANCE Collaborative Group.
Intensive blood glucose control and vascular outcomes in patients with type 2
diabetes. N Engl J Med 2008;358:2560–2572
3. Gerstein HC, et al. "Effects of Intensive Glucose Lowering in Type 2
Diabetes". The New England Journal of Medicine. 2008. 358(24):2545-59.
4. Department of Health and Human Services Center for Disease Control and
Prevention National Diabetes Fact Sheet: national estimates and general
information on diabetes and prediabetes in the United States. 2011.
5. Hemmingsen B, Lund SS, Gluud C, et al. Targeting intensive glycaemic control
versus targeting conventional glycaemic control for type 2 diabetes
mellitus. Cochrane Database Syst Rev. 2011;6
6. UK Prospective Diabetes Study (UKPDS) 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. Selvin E, Coresh J, Brancati FL. The burden and treatment of diabetes in elderly
individuals in the U.S.Diabetes Care. 2006;29:2415–2419.
8. Shorr RI, Ray WA, Daugherty JR, et al. Incidence and risk factors for serious
hypoglycemia in older persons using insulin or sulfonylureas. Arch Intern
Med. 1997;157:1681–1686.
9. AGS Choosing Wisely Workgroup. American Geriatrics Society identifies five
things that healthcare providers and patients should question. J Am Geriatr
Soc 2013; 61:622–631