New insights into the epidemiology and natural history of benign prostatic hyperplasia.

Benign Prostatic Hyperplasia (BPH) has undoubtedly been an important cause of the urinary difficulties observed in elderly men for many centuries although the condition was only recognised as such during the last century. Benign Prostatic Hyperplasia is a very common condition (88 per cent of autopsy specimens in men aged over 80 have histological BPH) and the cause of the commonest surgical procedure in elderly men (three men in ten ultimately may require surgery for this condition). A common cause of death in elderly men just 20-30 years ago, improved medical care has seen dramatic declines in this aspect of BPH and today treatment choices in BPH are largely determined by considerations of quality-of-life. Despite such a common occurrence, little is known with any certainty about the epidemiology of BPH. The incidence, even the population prevalence, is difficult to determine for a variety of reasons associated with difficulties surrounding the diagnosis of BPH and the identification of a source population to provide a denominator to calculate rates. Knowledge of risk factors is sparse: analytical epidemiologic studies of BPH are difficult to conduct. Case-control studies, the most commonly employed design in epidemiology, are problematic in that a control group may be difficult to define in view of the likelihood that a large proportion of these may have undiagnosed BPH. Against this background, knowledge of the prostate in the general population was sought in an international survey and found to be poor: although most men are aware of its existence, very few could correctly identify the function of the gland. Men tended to discuss urination problems with their doctors not when a symptom develops but when that symptom becomes bothersome. A 10-fold variation in frequency of rectal examination was identified between men in Germany and Italy which could not be explained by potential confounding variables. Given the large increases in the number of males reaching older ages, it is clear that BPH will continue to have substantial and increasing influence in terms of morbidity, mortality and health costs. Before the end of the present century, the life expectancy of a male at birth will exceed 80 years in many of the developed countries. Put put another way, one man in every two born can expect to reach an at which he has an 88 per cent chance of having a prostate with morphological BPH. Clearly, the need for high quality epidemiological information and consequent increased prospects for prevention is obvious.