Audiometric configuration as a reflection of low plasma glucose and diabetes.

Forty-five subjects with a rising, progressively improving (RPI) audiometric pattern were considered for a 5-hour oral-glucose tolerance test. Results revealed that 2 nondiabetic subjects (4%) had a plasma glucose nadir of 49 mg/dl or lower and 7 nondiabetic subjects had a nadir between 50 and 57 mg/dl. A total of 21% of 42 subjects with data indicated abnormally low readings. An additional 7 subjects were found to be diabetic; 5 subjects had impaired glucose tolerance, and 9 other subjects had nondiagnostic glucose intolerance, totalling 47% of 45 subjects in the study with abnormally elevated plasma glucose levels. Therefore a total of approximately 68% of all subjects in our study indicated metabolic dysfunction based specifically on a RPI pattern.

Audiometric configuration as a reflection of diabetes.

The purpose of this study was to investigate whether or not a rising, progressively improving (RPI) sensorineural hearing loss from lower toward higher frequencies might be related to or serve as an indicator or predictor of diabetes. Forty-five subjects between the ages of 21 and 79, demonstrating a RPI audiometric pattern, were considered for a 5-hour oral glucose tolerance test. Based on the National Diabetes Data Group standard, results showed that diabetes mellitus appeared in seven subjects; five subjects had impaired glucose tolerance; and nine subjects had mild but nondiagnostic glucose intolerance. Relatively normal glucose values were demonstrated by 53% of subjects. There may be some value in an RPI audiometric pattern as an indicator or early detection sign for diabetes, but further research is necessary before such conclusions can be drawn.

Loudness discomfort level for speech: comparison of two instructional sets for saturation sound pressure level selection.

This study was undertaken to compare the speech loudness discomfort levels (LDL's) with two instructional sets which have been proposed for saturation sound pressure level selection of hearing aids. The phraseology recommended by McCandless and by Berger was presented to normal-hearing and hearing-impaired listeners. The normal-hearing subjects obtained mean LDL's of 94.6 and 111.9 dB SPL for these respective instructions, which was statistically significant. The hearing-impaired listeners also showed LDL's with Berger's instructions (114.7 dB SPL) to be significantly higher than with McCandless' instructional set (109.3 dB SPL). Consequently, this investigation suggests that these two instructional sets may lead to substantially different saturation sound pressure levels. Further studies are needed to determine the most appropriate phraseology for LDL measurement, including the assessment of speech intelligibility at various saturation sound pressure levels. Another instructional set was constructed which (1) includes an explanation to patients of the purpose and importance of the test, (2) requests listeners to indicate the upper level they are "willing" to listen as opposed to the level they are "able" to listen, (3) instructs patients to search thoroughly around their LDL before making a final judgment, and (4) contains a statement that the LDL should be made with the understanding that the speech could be listened to for a period of time. Whatever instructions are used, clinicians are advised to interpret their LDL's very cautiously until validational studies are available.