Glycemic control and cardiopulmonary function in patients with insulin-dependent diabetes mellitus.
BACKGROUND
We studied cardiopulmonary function during exercise in young subjects with long-standing insulin-dependent diabetes mellitus (IDDM) who have no clinical cardiopulmonary disease to determine the relationships of aerobic capacity, gas exchange, ventilatory power requirement, and cardiac output to chronic glycemic control.


METHODS
Eighteen subjects with IDDM and 14 normal control subjects were studied. Nine diabetic subjects received twice daily insulin injections and had chronically elevated levels of glycosylated hemoglobin (hyperglycemic group); 9 other diabetic subjects received insulin via continuous infusion pumps and maintained chronic near-normal levels of glycosylated hemoglobin (normoglycemic group). At the end of at least 7 years of regular follow-up, aerobic capacity was determined by cycle ergometry. Lung volume, diffusing capacity, and cardiac output during exercise were measured by a rebreathing technique. Ventilatory power was measured by the esophageal balloon technique.


RESULTS
Maximal work load and oxygen uptake were markedly impaired in chronically hyperglycemic diabetic patients associated with significant restrictions of lung volume, lung diffusing capacity, and stroke index during exercise. Membrane diffusing capacity was significantly reduced at a given cardiac index. The normoglycemic patients consistently showed less impairment than the hyperglycemic patients.


CONCLUSIONS
Physiologically significant cardiopulmonary dysfunction develops in asymptomatic patients with long-standing IDDM. Chronic maintenance of near-normoglycemia is associated with improved cardiopulmonary function.
Niranjan
V
V
Department of Medicine, University of Texas Southwestern Medical Center, Dallas 75235-9034, USA.
McBrayer
D G
DG
Ramirez
L C
LC
Raskin
P
P
Hsia
C C
CC
D000328:Adult; D001794:Blood Pressure; D002248:Carbon Monoxide / Q000097:blood; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000503:physiopathology*; D004334:Drug Administration Schedule; D015444:Exercise; D005080:Exercise Test; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism*; D006334:Heart Function Tests; D006339:Heart Rate; D006801:Humans; D007260:Infusion Pumps; D007279:Injections, Subcutaneous; D007328:Insulin / Q000008:administration & dosage*; D008176:Lung Volume Measurements; D008297:Male; D009119:Muscle Contraction; D010101:Oxygen Consumption; D012119:Respiration; D012132:Respiratory Muscles; D013318:Stroke Volume
D002248:Carbon Monoxide; D006442:Glycated Hemoglobin; D007328:Insulin