Diabetes in the Pima Indians. Evidence of bimodality in glucose tolerance distributions

Venous plasma glucose levels two hours after a 75 gm. carbohydrate load were determined on over 2,900 Pima Indians, a population known to have an extremely high prevalence of diabetes mellitus. In each sex and in each decade above twenty-five years of age, the frequency distributions of the logarithms of the glucose levels were clearly bimodal, but below this age a single symmetrical unimodal distribution was found. A maximum likelihood procedure was used to derive the best fitting theoretical gaussian distributions for each group of data, together with the parameters of each distribution.

The observed bimodal distributions were found to be in satisfactory agreement with a model of two overlapping gaussian distributions, indicating that a logical separation between those with normal and high levels of glucose is possible, although the presence of overlap indicates that some misclassification will occur if any finite level is used to subdivide the population.

The data indicate that among the Pima: 1. The frequency distributions of two-hour glucose tolerance levels can be used to identify objectively and describe a hyperglycemic population without recourse to other criteria for diabetes. 2. There are small changes in the parameters of “normal” glucose tolerance between the ages of twenty-five and sixtyfour years. 3. The increase in mean glucose level found with rising age in this population is mainly the result of an increasing proportion of subjects who are in the group characterized by marked glucose intolerance.

The bimodal distributions of plasma glucose levels The bimodal distributions of plasma glucose levels among the Pima Indians contrast with those described so far in other groups. It seems likely that differences are attributable to the lower prevalence of diabetes elsewhere which would obscure the identification of bimodality.

Periodontal disease and blood citrate levels in patients with trisomy 21

Elevated blood-citrate levels, poor oral hygiene, and macroglossia were associated with early, severe periodontitis in mongoloids.

Congenital anomalies and diabetes in the Prima Indians of Arizona

Medical records of 1,207 Pima Indian children were examined for reported congenital anomalies. Anomalies occurred in eight (38.1 per cent) of twenty-one offspring born after the onset of diabetes to mothers whose disease was diagnosed before age twenty-five, but in only 3.7 per cent of the offspring of all other women. Children born after the onset of diabetes to mothers whose disease started at or after age twenty-five, and those born to prediabetic mothers had anomalies no more frequently than the children of nondiabetic mothers. Congenital anomalies were not related to paternal diabetes. Anomalies were more frequent in children from “diabetic” pregnancies during which the mother required hypoglycemic medication than from those during which medication was not required. Although a genetic mechanism cannot be completely excluded, the data better support the hypothesis that diabetes produced fetal anomalies among the Pima Indians by its influence upon the intrauterine environment during early pregnancy.

A double blind comparative trial of pericyazine and thioridazine in chronic schizophrenia

Pericyazine (“Neulactil”), introduced in 1961, is a phenothiazine with tranquillizing and stimulating properties.

Diabetes in the Cocopah Indians

One hundred and eighty-two Cocopah Indians, aged five years and over and representing 81 per cent of the study population, were given a 75 gm. glucose equivalent load and determinations were made two hours later of plasma glucose levels. Seventeen per cent of the population at the time were either receiving hypoglycemic therapy or had plasma glucose levels of at least 160 mg. per 100 ml., which was considered indicative of “diabetes.” In those aged thirty-five years and over, the prevalence was 34 per cent, similar to that reported in the Cherokee but lower than that in the Pima Indians.

The frequency of obesity in those aged fifteen and over was higher in the Cocopah than in the Pima Indians but, as the prevalence of “diabetes” was lower in the Cocopah, the frequency of obesity did not appear to account for the difference in the prevalences of diabetes between these tribes.

Determination of traces of organic fluorine in hydrocarbons

Organic samples containing down to 0.2 ppm of fluorine may be analysed by first converting the organic fluorine into inorganic fluoride by treatment with sodium biphenyl, followed by removal of diverse cations with a cation-exchanger before conductometric titration with lanthanum acetate. Effect of variables, sources of error, and control of reagent blanks are evaluated. For the 0.2-1 ppm organic fluorine level in synthetic blends made from 1-fluoronaphthalene, the relative estimated standard deviation was 7.8%; the mean relative error was 6.2 %. Based on the mean range from duplicate analyses of catalytically processed samples in the C(12) boiling range, at the 1 ppm fluorine level the estimated standard deviation was 0.087 ppm of fluorine. One analyst can determine the fluorine content of about 12 samples in 8 hr.