“…Moreover, an Italian survey on radiological, scintigraphic and biochemical data, showed that the prevalence of PDB in Italy, unlike the studies on British descent populations, did not exhibit a decreased secular trend [10]; (ii) a significant decline of the PDB-related mortality has been more recently reported in a US study (population of Olmsted County, MN) in which it has been showed that overall survival in the PDB analysed population was slightly better than expected when compared with white Minnesota residents, especially in affected male. Moreover, an increased risk of mortality resulting from cancer, cardiovascular disease, pulmonary disease or gastrointestinal disease has not been reported in this study [11]; (iii) a drastic fall down of PDB prevalence (standardized both for age and gender) between 1974 and 1994 (follow-up prevalence study in 10 towns in Great Britain), as also observed in other European Countries; on the contrary, a previous US survey on the incidence of PDB (still from Olmsted County, MN), covering the period 1950 through 1994, revealed an increased incidence over the first part of the study period and then a decline [12].…”