Tajar and colleagues present the associations between moderate and severe hypogonadism,symptoms of androgen deficiency and the prevelence of end-organ evidence of androgen deficency in 2966older men in the European Male Aging Study.They find lower muscle mass,reduced bone mineral density,anemia,insulin resistence,metabolic syndrome and cardiovascular disease,with greater risks of these signs of androgen deficiency at lower serum testosterone concentrations.