High-density lipoprotein cholesterol strongly discriminates between healthy free-living and disabled octo-nonagenarians: a cross sectional study. Associazione Medica Sabin.

Aging is frequently associated with a deterioration in health and functional status, which often induces important modifications in several biological parameters, including plasma lipids; as a consequence, the real "meaning" of lipoprotein parameters in old individuals is complex. A cross sectional study was carried out in order to investigate the lipoprotein profile in very old individuals with or without disability, and evaluate the possible influence of other biological variables on plasma lipids. One hundred selected healthy free-living (FL) and 62 disabled (DIS) subjects aged over 80 were enrolled; 91 healthy adults matched for origin were included as controls. Lipoprotein profile [total cholesterol, triglycerides, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol, apoprotein A-I and B], anthropometric parameters, and ADL were measured. The FL octo-nonagenarians featured higher HDL-cholesterol levels than adult controls. DIS octo-nonagenarians showed lower total and HDL-C levels than FL. Discriminant analysis indicated that HDL-cholesterol and apoprotein A-I, but not total cholesterol, strongly discriminated between FL and DIS octo-nonagenarians. Multivariate analysis demonstrated that the waist/hip ratio, an index of visceral adiposity, was negatively associated with HDL-C levels in FL, but not in DIS elderly. We conclude that: 1) in very old individuals, the absence or presence of disability is strongly associated with high or low HDL-cholesterol values, respectively; 2) HDL-C and apo A-I are the parameters which better discriminate between FL and DIS octo-nonagenarians; and 3) the differences in HDL-C levels between FL and DIS are not due to modifications in anthropometric parameters. Prospective studies are needed to better understand the relationship between high-density lipoprotein levels, disability and aging.

[Study of the binding between uric acid and plasma proteins (author's transl)]. / Richerche sui legami esistenti tra acido urico e proteine plasmatiche.

The Authors have analyzed the complex problems of the possible binding between uric acid and plasma proteins using two methods consisting of serum ultrafiltration at 22 degrees C or electrophoresis on different supports with successive specific coloration of the free and bound uric acid. The percentage of free and bound uric acid was established in serum from normal subjects, patients with primary gout, patients with renal insufficiency treated by dialysis and subjects with type IV dyslipidemia. The Authors discuss the results obtained as regards the possible role played by urate-plasma proteins binding in the interpretation of a genetic defect present in gouty patients involving a diminished uric acid binding capacity of plasma proteins.