ABSTRACT
The purpose of this study is to establish the normal physiological values of glycosylated hemoglobin (HbA<SUB>1</SUB> and HbA<SUB>1C</SUB>) among Japanese rural inhabitants and to evaluate its potential as a screening tool for diabetes mellitus. Six hundred and seventy-five people aged 35-64 years (210 males and 465 females) were examined. Oral glucose tolerance tests were perfomed on 135 inhabitants of them by giving a 50-gm.<BR>Frequency distributions of HbA<SUB>1</SUB> and HbA<SUB>1C</SUB> fitted approximately to the log-normal distribution.<BR>Geometric means and standard deviations in bracket were 7.95 (1.11)% for HbA<SUB>1</SUB> in men, 8.13 (1.12)% for HbA<SUB>1</SUB> in women, 5.17 (1.10)% for HbA<SUB>1C</SUB> in men and 5.16 (1.11)% for HbA<SUB>1C</SUB> in women<BR>Group average values of HbA<SUB>1</SUB> and HbA<SUB>1C</SUB> tended to increase with age in both men and women except a male group aged 60 years and over. There were no significant differences between mean values of glycosylated hemoglobin in men and those in women. HbA<SUB>1</SUB> was positively correlated with age in women and negatively correlated with hemoglobin in both men and women. HbA<SUB>1C</SUB> was positively correlated with age in men and women, body mass index, systolic blood pressure and serum cholesterol in women, and negatively correlated with hemoglobin in men.<BR>In order to evaluate glycosylated hemoglobin as a screening tool for the identification of unknown persons with diabetes, we calculated the sensitivity (the extents to which the participants who were found to have a diabetic OGTT also had an abnormal glycosylated hemoglobin) and specificity (the extents to which the participants who were not diabetic had normal glycosylated hemoglobin). The sensitivities for the person aged 59 years or under using HbA<SUB>1</SUB> were 72.7-100% and the specificities 67.3-75.0 percent. Futhermore the sensitivities for the same aged person using HbA<SUB>1C</SUB> were 81.8-100% and the specificities 78.8-81.3 percent. The validities for both HbA<SUB>1</SUB> and HbA<SUB>1C</SUB> were higher than those for glucosuria or blood glucose. But glycosylated hemoglobin was not useful as a screening tool for the person aged 60 years and over because of the low specificity.
ABSTRACT
A follow-up study was conducted until the end of 1980 on 28, 643 rural inhabitants who had undergone mass health screening between 1971 and 1978. For those who died, the causes of death were confirmed by death certificates.<BR>The results obtained were as follows:<BR>1) During the observation period, there were 876 death (about 3% of participants). The mortality was three times greater for males than for females and increased with age. These differences between sexes were statistically significant except the group of 29years old or under.<BR>2) Forty-two percent of the total deaths were for cerebro-cardiovascular diseases, 32% for malignant neoplasms and 26% for others. For males, the mortality of cerebro-cardiovascular diseases was greater than those of other causes of death. On the other hand, the mortality of malignant neoplasms was higher among females.<BR>3) The mortality rate per 1, 000 person-years of observation was 5.2 (11.8 for males and 3.2 for females). Cause- specific mortality rates were 1.7 per 1, 000 person-years for malignant neoplasms (3.1 for males and 1.2 for females); 1.2 for cerebrovascular diseases (2.8 for males and 0.7 for females), 0.9 for cardiovascular diseases (2.3 for males and 0.5 for females), 0.3 for accidents and 0.2 for pneumonia. The mortality rates of each aged-group according major causes of death were higher among males than among females except two groups of 29 years old or under and 70 years old or over of cerebral bleeding.