Somatopause and Elderly GHD – Similarities and Differences Horm Res 2003;60(suppl 1):102–104 DOI: 10.1159/000071233 Effects of Ageing on Insulin Secretion and Action Niels Møller Lars Gormsen Jens Fuglsang Jakob Gjedsted Medical Department M (Endocrinology and Diabetes) and Institute of Experimental Research, University of Aarhus, Aarhus, Denmark Dr. N. Møller Medical Department M (Endocrinology and Diabetes) and Institute of Experimental Research, University of Aarhus DK–8000 Aarhus (Denmark) Tel. +45 89 49 21 65, Fax +45 89 49 20 10, E-Mail nielsem@dadlnet.dk ABC Fax + 41 61 306 12 34 E-Mail karger@karger.ch www.karger.com © 2003 S. Karger AG, Basel 0301–0163/03/0607–0102$19.50/0 Accessible online at: www.karger.com/hre Key Words Insulin W Insulin resistance W Ageing W Type 2 diabetes mellitus W Insulin secretion Abstract One of the many conditions associated with ageing is type 2 diabetes mellitus, the prevalence of which in- creases from 20–30 years of age onwards. In many cases, type 2 diabetes mellitus is caused by the combina- tion of insulin resistance and poor insulin secretion. Insu- lin resistance is also a risk factor associated with other disorders, in particular cardiovascular disease. Physio- logical changes associated with ageing, such as changes in body composition, decreased physical fitness, changes in hormones, and the secondary effects of high levels of free fatty acids and glucose, may also contribute to the impairment of insulin secretion and action. In this review, the effects of ageing on the secretion and action of insulin will be highlighted. Copyright © 2003 S. Karger AG, Basel Introduction Propelled by the ever-growing world population and the continual rise in life expectancy, ageing is becoming a more frequent and lengthy ‘condition’. The process of ageing is characterized by a number of physiological and pathophysiological alterations, which, in many cases, can lead to impaired physical performance and increased morbidity and mortality. Type 2 diabetes mellitus (non- insulin dependent) is such an example. Data from the Framingham Study show unequivocally that the inci- dence of type 2 diabetes rises steeply with age, at an almost exponential rate, from the age of 20–30 years onwards [1]. Prevalence rates show a similar pattern from 1% between 30 and 40 years of age to more than 15% above 80 years of age. These observations were published in 1986 and both the incidence and prevalence rates are continuously rising because of increased life expectancy, increased prevalence and magnitude of obesity, and poor inclination to physical activity. The picture becomes even more alarming when one considers pre-diabetic states. Type 2 diabetes is, in most cases, caused by a combination of defective insulin secretion and insulin resistance. At present, there is accumulating evidence that insulin resis- tance is a substantial risk factor for cardiovascular disease [2, 3]. The terms ‘metabolic syndrome’, ‘insulin resistance syndrome’, ‘syndrome X’, ‘dysmetabolic syndrome’ and others have been proposed to represent the clustering of insulin resistance, obesity, hypertension, dyslipidaemia and hypercoagulability. According to World Health Orga- nization criteria, the metabolic syndrome is defined as the coexistence of insulin resistance and two out of the fol- lowing four conditions: (1) obesity, (2) dyslipidaemia, Downloaded by: 198.143.37.97 - 4/6/2016 7:32:54 PM