Patterns of morbidity and mortality have always varied from time to time and these variations have been most marked since the beginning of the last century. In the past, when bacteriology was yet in its infancy, and chemotherapy had not even been thought of, infectious diseases accounted for the greater part of morbidity and mortality throughout the world. Periodical epidemics and pandemics of the major infectious diseases such as Plague, small -Pox and cholera were a common occurrence, and these contributed in no small measure towards maintaining the average life -expectancy at a comparatively low level. However, with improvement in the knowledge of the aetiology of most diseases, and the advent of chemo- therapy and antibiotics, the risk of People succumbing to such diseases has been greatly reduced. The average life expectancy has increased considerably in almost all parts of the world, and, as one would normally expect, the more chronic diseases such as diabetes mellitus, arteriosclerotic and degenerative heart disease and also malignant diseases have begun to occupy important roles in the overall mortality picture at the present day.
Notwithstanding the great volume of research into the aetiology and pathogenesis of arteriosclerotic heart disease and diabetes mellitus, there are certain aspects of these diseases which have not yet been fully investigated. Survivorship among diabetics, and the exact causation of their deaths are two such problems. Although diabetes mellitus has always been considered as an important cause of morbidity and mortality throughout the world and referred to as such even in the oldest medical texts, (1)(2)statistical data relating to survival and underlying causes of death are few and are available only for a few countries of the world.
We have, therefore, been interested to find out what happened to people once the diagnosis of diabetes mellitus was made, as to how long they lived and what effect the diabetic state had on their working capacity and general health and well-being.
In order to do this, an enquiry was designed, with a view to obtaining further information regarding survivorship and underlying causes of death of patients who suffer from diabetes mellitus. The study is based primarily on the follow -up of two cohorts of individuals who had attended the diabetic clinic at the Royal Infirmary, Edinburgh, for diagnosis and treatment of glycosuria during the years 1939/191+0 and 1949/1950. Only those patients residing in the South Eastern Region of Scotland (with the exclusion of Fife), and those who were actually confirmed as suffering from diabetes were considered in the study.
The total number of patients in both groups was 959. Of these, we were able to trace the death certificates of 632 patients who had died subsequently at some time or another. Of the remainder, we saw and interviewed 21+9 patients. ';,e were also in contact with a further 35 patients and were able to confirm that they were alive, although we were unable to interview them personally for reasons given later.
The remaining 43 patients we were unable either to interview or contact by letter.
This thesis will discuss in detail the general question of survivorship of patients once the diagnosis of diabetes mellitus has been made, the cause of death in patients suffering from diabetes mellitus, and the particular results obtained in the enquiry that we have conducted.