Objective: The aim of the present study was to clarify the relationship between GH deficiency (GHD) andsome cardiovascular risk factors and to analyse the effect of GH replacement therapy in a large numberof patients over a prolonged period of time.Design: Data for analysis were retrieved from KIMS (Pfizer International Metabolic Database). Serumconcentrations of total cholesterol, high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein(LDL)-cholesterol and triglycerides were obtained from 2589 patients at baseline and from 1206patients after 1 and 2 years of GH replacement therapy. Body mass index (BMI), waist and hip, restingblood pressure and body composition were also measured.Results: At baseline, the unfavourable effects of GHD were most obvious in the lipid profiledemonstrating elevated mean total and LDL-cholesterol, in the increased waist circumference and theelevated BMI. The cholesterol concentration, BMI and body composition were significantly adverselyaffected by a number of factors, including age, sex and the use of anti-epileptic drugs. The therapeuticeffect of GH was essentially uniform across the whole population. GH replacement reduced significantlythe mean total and LDL-cholesterol, the waist circumference and the fat mass and was maintainedduring 2 years.Conclusions: This analysis of a large number of patients confirmed that GHD adults present with anincreased cardiovascular risk. The sustained improvement of the adverse lipid profile and bodycomposition suggests that GH replacement therapy may reduce the risk of cardiovascular disease andthe premature mortality seen in hypopituitary patients with untreated GHD.