NIDDM in the elderly.
OBJECTIVE
We conducted this study to assess the metabolic alterations in elderly patients with NIDDM.


METHODS
Healthy, lean (n = 15; age, 73 +/- 1 years; BMI, 23.8 +/- 0.5 kg/m2), and obese (n = 10; age, 71 +/- 1 years; BMI, 28.9 +/- 1.2 kg/m2) control subjects and lean (n = 10; age, 75 +/- 2 years; BMI, 24.0 +/- 0.5 kg/m2) and obese (n = 23; age, 73 +/- 1 years; BMI, 29.9 +/- 0.7 kg/m2) NIDDM patients underwent a 3-h glucose tolerance test, a 2-h hyperglycemic glucose clamp study, and a 3-h euglycemic glucose clamp study with tritiated glucose methodology to measure glucose production and disposal rates.


RESULTS
Waist-to-hip ratio (WHR) was greater in both lean and obese NIDDM patients than in control subjects. Insulin responses during the oral glucose tolerance test were similar in obese subjects (control subjects: 417 +/- 64 pmol/l; NIDDM patients: 392 +/- 47 pmol/l) but were reduced in lean NIDDM patients (control subjects: 374 +/- 34 pmol/l; NIDDM patients: 217 +/- 20 pmol/l, P < 0.01). Lean and obese NIDDM patients had absent first-phase insulin responses during the hyperglycemic clamp. Second-phase insulin responses were reduced in lean (P < 0.01 vs. control subjects by analysis of variance) but not obese NIDDM patients. Hepatic glucose output was not increased in lean or obese NIDDM patients. Steady-state (150-180 min) glucose disposal rates were 16% less in lean NIDDM patients (control subjects: 8.93 +/- 0.37 mg.kg LBM (lean body mass)-1.min-1; NIDDM patients: 7.50 +/- 0.28 mg.kg LBM-1.min-1, P < 0.05) and 37% less in obese NIDDM patients (control subjects: 8.17 +/- 0.38 mg.kg LBM-1.min-1; NIDDM patients: 5.03 +/- 0.36 mg.kg LBM-1.min-1, P < 0.001).


CONCLUSIONS
Lean elderly NIDDM patients have a profound impairment in glucose-induced insulin release but mild resistance to insulin-mediated glucose disposal. Obese elderly NIDDM patients have adequate circulating insulin, but marked resistance to insulin-mediated glucose disposal. Hepatic glucose output is not increased in elderly NIDDM patients.
Meneilly
G S
GS
Department of Medicine, University of Sherbrooke, Quebec, Canada.
Elliott
T
T
Tessier
D
D
Hards
L
L
Tildesley
H
H
D000368:Aged; D001786:Blood Glucose / Q000187:drug effects / Q000378:metabolism; D001794:Blood Pressure; D015992:Body Mass Index; D003920:Diabetes Mellitus / Q000097:blood / Q000503:physiopathology*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000503:physiopathology*; D005260:Female; D015309:Glucose Clamp Technique; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000097:blood / Q000494:pharmacology; D008297:Male; D009765:Obesity / Q000097:blood / Q000503:physiopathology*; D010101:Oxygen Consumption; D012016:Reference Values; D013008:Somatotypes
D001786:Blood Glucose; D007328:Insulin