This article is more than 5 years old. Information may no longer be current.
Intensive glycemic control preserves muscle strength in patients with type 2 diabetes, heart failure
In patients with type 2 diabetes and chronic heart failure, 4 months of intensive glycemic control had no adverse effect on left ventricular contractile reserve or aerobic capacity, according to results from a randomized study.
Roni Nielsen, MD, of the department of cardiology at Aarhus University Hospital and the department of medicine at Viborg Hospital in Denmark, and colleagues analyzed data from 39 adults with chronic heart failure and poorly controlled type 2 diabetes (HbA1c 7.5%) recruited between September 2010 and November 2012. Researchers randomly assigned participants to an HbA1c optimization group (HbA1c target < 7.5%; n = 20) or a non-optimization group (drug therapy intensified if HbA1c reached > 10%; n = 19); all patients were assigned to an outpatient diabetes clinic and told not to change medications unless instructed to do so. Participants optimized glucose profile with daily blood glucose assessments, adjustment of insulin dosage, use of oral antidiabetic medication and advice from dietitians during contact at the outpatient clinic. Patients in the non-optimization group were instructed to continue any prescribed antidiabetic medications and usual care.
Patients provided blood samples and underwent stress echocardiography, a cardiopulmonary exercise test, 6-minute hall-walk test, muscle strength (hand grip) examination and DXA scans at baseline and follow-up.
In the optimized group, mean HbA1c fell by 0.9% between baseline and follow-up (8.4% to 7.6%), whereas the non-optimized group experienced no change (8.3% to 8.4%; P < .001). There were no between-group differences for myocardial contractile reserve (P = .18), oxygen consumption (P = .55), exercise capacity (P = .12) or 6-minute walk test (P = .84).
In the non-optimized group, muscle strength decreased by –2.4 kg but remained stable in the optimized group (P = .01), without any differences in baseline values. Researchers observed a nonsignificant decrease in lean and fat tissue mass in the non-optimized group. Hypoglycemia and fluid retention did not differ between groups.
“Medical treatment [in the optimization group] was predominantly adjusted through an increase in insulin dosage, which is otherwise known to cause fluid retention and may have unfavorable effects in patients with [type 2 diabetes] and [heart failure],” the researchers wrote. “Our findings are intriguing and useful because they indicate that an increase in insulin dosage does not give rise to weight gain, does not worsen symptoms and entails no deterioration in left ventricular reserve function or [cardiopulmonary exercise] capacity in these patients when glycemic levels are optimized.” – by Regina Schaffer
Disclosure: The study was supported by an unrestricted grant from the Danish Diabetes Association. The researchers report no relevant financial disclosures.