Evaluation of rosiglitazone administration on cardiovascular function in severe obesity.
BACKGROUND
Obese patients have myocardial structural and functional alterations related to insulin resistance.


OBJECTIVE
The purpose of the study was to analyze the effects of rosiglitazone, an insulin sensitizer agent, on cardiac morphometry and functioning.


METHODS
In 2 groups of sex- and age-matched, nondiabetic, obese patients (5 men and 7 women, age 19-51 y; group A: body mass index [BMI] 40.6 +/- 3.4 kg/m(2); group B: BMI 42.6 +/- 2.7 kg/m(2)), we evaluated the basal insulin sensitivity index (HOMA[IS]), body composition by bioelectrical impedance analysis and 24-h blood pressure monitoring. Furthermore, all patients underwent conventional 2-Dimensional and color Doppler echocardiography, and pulsed-wave tissue Doppler imaging (TDI). After the baseline evaluation, all patients were put on a hypocaloric diet (70% basal metabolic rate) plus placebo if they were in group A, or plus rosiglitazone (4 mg twice daily; Avandia [GlaxoSmithKline plc., Brentford, Middlesex, United Kingdom]) if they were in group B, for 6 mo.


RESULTS
Significant decreases in body weight, total fat mass, BMI, and systolic blood pressure were registered in both groups. Rosiglitazone administration appeared more efficient in improving HOMA(IS) (mean difference: 0.30 +/- 0.19 versus 0.11 +/- 0.21, p < 0.05). Left ventricular (LV) diastolic diameter (49.4 +/- 7.7 versus 52.3 +/- 5.4 mm, p < 0.05) and E wave (0.89 +/- 0.18 versus 0.99 +/- 0.20 m/sec, p < 0.05) increased in the rosiglitazone group due to a rise in preload and water content without peripheral edema. The increase in systolic (Sa) wave velocity in both groups was probably a result of the general improvement in insulin metabolism and the decrease in blood pressure.


CONCLUSIONS
We confirmed the positive effect of rosiglitazone on glucose metabolism in obese, nondiabetic patients, but changes in insulin sensitivity did not explain the cardiac effects produced by further mechanisms.
Brunani
Amelia
A
Department of Internal Medicine, IRCCS, Istituto Auxologico Italiano, Verbania, Italy. brunani@auxologico.it
Liuzzi
Antonio
A
Titon
AnnaMaria
A
Graci
Salvatore
S
Castagna
Giovanna
G
Viberti
Gian Carlo
GC
Gondoni
Luca A
LA
D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D002319:Cardiovascular System / Q000187:drug effects*; D003971:Diastole / Q000502:physiology; D015150:Echocardiography, Doppler; D005260:Female; D006801:Humans; D007328:Insulin / Q000378:metabolism; D007333:Insulin Resistance / Q000502:physiology; D008297:Male; D009765:Obesity / Q000503:physiopathology*; D047495:PPAR gamma / Q000494:pharmacology*; D000077154:Rosiglitazone; D013599:Systole / Q000502:physiology; D045162:Thiazolidinediones / Q000494:pharmacology*; D016277:Ventricular Function, Left / Q000187:drug effects*
D007328:Insulin; D047495:PPAR gamma; D045162:Thiazolidinediones; D000077154:Rosiglitazone