=3 .sx RESULTS .sx Classification of the Population .sx EVERY person living in the village who was over the age of five years had been asked to supply a specimen of urine , and to answer a questionnaire ( Table 2) .sx The very young children were not tested because apart from any practical difficulties , the florid manifestations of diabetes at this age seem to make it unnecessary , though in any subsequent survey we should like to include this age group .sx ,071 males and 2,034 females were tested which makes an 81% response of the population over the age of five years .sx Details of thirty-three previously diagnosed cases of diabetes were collected from the general practitioners' and clinic records , one of these was a boy under the age of five so that the total examined is therefore 4,105+1 .sx As far as can be determined the 19% of non-cooperators were not different in age or other environmental factor from the rest , and in calculating rates , it has been assumed that they are a random sample of the whole population .sx However , in testing the significance of possible aetiological factors , further consideration has been given to this and any affect [SIC] of selection has been excluded as rigorously as possible .sx The normal portion of the population , in whom no glycosuria was found at the time of examination has been used as a control group .sx Only those discovered to have glycosuria were asked to undergo a glucose tolerance test as the known diabetics had been previously verified and were already under treatment .sx It is found that the blood sugar curves we obtained show a gradual rise in continuous sequence from the normal to the diabetic , and three arbitrary divisions have been made , and , because a true glucose method of blood sugar estimation was used , the levels considered important are 160 mgm% at 1 hour , 140 mgm% at 1 1/2 hours , and 120 mgm% at 2 hours ( Conn 1958) .sx These levels were taken to divide the intermediate and lower blood sugar curves , and it is of interest that this level separates the cases of transient or intermittent from those of constant glycosuria .sx As there is no universal agreement about the actual lower levels of blood sugar in diabetes the appearance of the whole curve was noted , and particular attention was paid where it had not returned to the fasting level at two hours .sx Thus our grouping of the examined population is classified as follows :sx - A. The unaffected population or control group of 3,916 persons .sx B. Known diabetics , 33 .sx C. Glycosurics , 167 .sx The glycosurics in turn are subdivided according to their blood sugar curves ( Diagrams 1 and 2) .sx a. Latent diabetics , with high type of curve , 25 .sx b. Intermediate .sx In 42 cases the blood sugar levels rose to , or only just above 160 mgm% at 1 hour , 140 mgm% at 1 1/2 hours , 120 mgm% at 2 hours .sx c. Transient or intermittent glycosurics with low or normal blood sugar levels , 75 .sx d. A group of 25 glycosurics on whom no test was performed .sx It is estimated that the total percentage of known diabetics in Ibstock is between 1.3% and 1.4%. If we can take Ibstock to be a random sample of the general population of Britain , the 95% confidence limits for the average incidence in Britain are 1.0% and 1.6% , but , in fact , it is possible that it is not exactly comparable and the limits should be wider .sx It is interesting to note that this range includes the results found in other similarly conducted surveys of whole population groups ( Table 4) .sx Discussion of the Abnormal Groups .sx The Known Diabetics ( Diagram 4a ) .sx The thirty-three previously diagnosed diabetics form a somewhat artificial group owing to the duration of their disease and its treatment , and because they knew they were diabetic when they answered the questions .sx Wherever this could bias a result in testing the significance of any factor , this group has been excluded .sx On the other hand , the others did not know the result of the tests at the time of answering the questionnaire , and this makes these results of particular statistical interest .sx In considering the known cases diagnosed and under treatment at the time of the survey , twenty-nine were already on the general practitioners' lists , but during the year , they found three more men and the boy under five years old , all of whom had indisputable symptoms and signs , thus a total of nine males and twenty-four females are put to their credit .sx These cases have all been examined at the diabetic clinic of the Leicester Royal Infirmary although they were not all traced until the end of the survey .sx We think it is most improbable that any previously diagnosed diabetic is now unrecorded so that the percentage figure for known cases , when estimated on the whole population of 5,406 , = 0.61%. In diagram 3 an attempt has been made to indicate the extent of the assumed diabetic problem in this small community before any search had been made for the latent cases .sx It shows the distribution of the known diabetics according to their age and year of diagnosis .sx Superimposed are the diabetics known to have died in Ibstock since 1940 , which has been taken as a base line because it was the year in which the living case of longest duration was diagnosed .sx It will be noticed that there are now no diabetics living in Ibstock who were diagnosed after the first two cases for another four years .sx Some may have left the village ; there are three deaths recorded during this time , but the possibility is that , as these were war years and food rationing was in force , the elderly , mild and obese diabetics might have been sufficiently controlled by increased activity and less food to have remained latent and symptom free , and even free of glycosuria .sx Since 1951 the average number of new diabetics diagnosed has been four 6per annum and these have all presented with symptoms .sx The Latent Diabetics ( Diagram 4b ) .sx Out of the newly discovered glycosurics , 25 persons- 11 men and 14 women- show the frankly diabetic type of glucose tolerance curve ( Diagrams 1 and 2) .sx Estimated on the examined population of 4,105 , this gives the percentage for latent diabetes in Ibstock as 0.67%. No history of thirst , polyuria nor loss in weight was given and these people were unsuspected by themselves or their doctors .sx No physical examination of the complete group has been achieved owing to the reluctance on the part of the individuals to attend the diabetic clinic for the purpose , but the general practitioners have marked their record cards with coloured indicators so as to keep them under their particular scrutiny .sx They have also allowed the health visitor for diabetics in the County of Leicestershire to call and give any necessary dietetic instruction and to institute a regular follow up service of urine testing and weighing .sx This group of latent diabetics were all over forty years of age , most were considerably over weight ; none have yet required regular insulin treatment .sx Intermediate Group of possible Pre-diabetics ( Diagram 4c ) .sx Abnormal glucose tolerance curves were obtained in forty-two of the glycosurics examined , and although not reaching the characteristic levels used for diagnosing diabetes , they correspond to the criteria put forward by Conn ( 1958) .sx The lower limits of the group were defined by the blood sugar levels of 160 , 140 , 120 mgm% at 1 , 1 1/2 , and 2 hours respectively , and with the exception of three cases this level separated the constant from the transient glycosurics .sx The upper levels naturally merge into the lower diabetic curves .sx It will be shown later in the analysis of certain factors that this seems to be an important group of probable pre-diabetics .sx The younger people show this change as well as the older and there was a considerable excess of young men , 30m :sx 12f .sx Although it was a practical impossibility to perform cortisone glucose tolerance tests ( Conn 1958 ) , ( Fajans and Conn 1959 ) , in this group of people at the time of the survey , it is an investigation which might be of great value , as it would also be to perform serial glucose tolerance tests at for example , one or two year intervals .sx The general practitioners have again tagged the medical record cards of these people with a different coloured indicator so that at any attendance at the surgery the possibility of diabetes is remembered and any significant data noted .sx It should be of interest to see if this amount of clinical supervision will alter the natural effect of time and have a preventive action .sx Transient or Intermittent Glycosuria ( Diagram 5a ) .sx In the group of glycosurics with normal glucose tolerance tests , the age range was 5 to 81 ( Table 3) .sx There were 48 males and 27 females .sx There were only three cases of constant glycosuria which satisfy the stricter definition of renal glycosuria , i.e. , the constant passage of glucose in the urine at normal or sub-normal blood sugar levels .sx Transient glycosuria with normoglycaemia may indicate transient lowering of renal threshold as is commonly found in pregnancy , and it may be that as with pregnancy there is an increased liability to the development of diabetes .sx It seems wise to keep an open mind and to follow up these cases with urine and possibly blood sugar estimations at a later date to measure the true significance of this finding .sx It should also be recalled that the faintest change in colour of the Clinistix was taken as positive .sx Glycosurics on whom no Glucose Tolerance Tests were performed ( Diagram 5b ) .sx Twenty-five glycosurics , for one reason or another , were not subjected to blood sugar examination .sx It is probable that three were diabetic ; one of whom , a woman , died of coronary artery occlusion before the test could be arranged .sx Case 205 f. Her husband was found to be diabetic in the survey and a clinical impression suggested that this was a case of conjugal diabetes .sx Case 1082 f. Short and stout , utterly refused further tests .sx Case 1568 f. Minimal glycosuria , pregnant and left Ibstock .sx Case 2081 f. Recently discharged from mental hospital .sx Case 3112 f. Glycosuria found during an attack of influenza .sx On re-testing she was sugar free .sx Case 3352 f. On re-testing no glycosuria was found .sx Case 3458 f. Urine only faintly positive .sx Her doctor reported that she was " a hermit type " and unlikely to co-operate .sx Case 3429 f. Aged 82 and too old and feeble to be troubled .sx Case 118 m. Paranoid schizophrenic , difficult and dangerous .sx Case 133 m. Aged 81 .sx Too old and frail .sx A second specimen of urine was negative .sx Case 1088 m. Refused to lose time from work .sx Case 1286 m. Improvident and careless ; wife is a severe diabetic .sx Case 1666 m. Mother diabetic , but he did not wish to be off work for the morning .sx Case 1672 m. He and three sons gave a history of investigation for " renal glycosuria " 25 years ago .sx It is probable that the remaining men were not prepared to give up time from work to come for the test .sx Changes since the Survey .sx Since the field work finished , two diabetics have returned to live again in Ibstock where they were originally diagnosed , both in 1951 .sx A boy who was 2 1/2 years old at onset had been staying at a residential home for diabetic children in the south of England as his home environment was not good .sx The other is a woman who was diagnosed at the age of 51 .sx Her mother was diabetic and she is short and stout and does not require insulin .sx Three new diabetics were diagnosed by their doctors in 1959 , two of whom had been tested in the survey .sx A man of 25 developed diabetes in the acute form and requires insulin .sx A woman of 54 who was negative in the survey but now requires to be dieted strictly .sx The third , an obese woman , had previously refused to be tested or she might well have come under treatment sooner .sx These changes have been mentioned to show the continuity of the pattern of the condition we are examining but have not , of course , been taken into account in the statistical sections as they would introduce bias .sx