Palatability, glycemic, and insulinemic responses to various carbohydrate formulations: Alternatives for the diagnosis of insulin dysregulation in horses?

BACKGROUND: Oral glycemic challenge (GC) tests are recommended for diagnosis of insulin dysregulation (ID). Various protocols are used, but all have limitations in terms of palatability, ease of use, variable composition, geographic availability, or some combination of these. HYPOTHESIS/OBJECTIVE: To evaluate newly developed formulations with defined carbohydrate composition for use as oral GCs. ANIMALS: Thirty-four horses and ponies in various metabolic states. METHODS: Our objectives were carried out in 2 separate cross-over experiments. First, the palatability and acceptance of various GCs (2 syrups, 1 granulate) offered for free intake were compared to glucose mixed in a chaff-based diet. Subsequently, syrups were administered by syringe and compared to an oral glucose test using naso-gastric tubing (tube OGT) to investigate the glycemic and insulinemic responses. Second, these variables were compared in the best performing GC-formulations (granulate further optimized to pelleted formulation and 1 syrup) and a tube OGT. All GCs were administered with equivalent amounts of 0.5 g glycemic carbohydrates per kg body weight. RESULTS: Only the GC pellets were consumed completely by all horses (consumption time 5 ± 2 min). When administered by syringe, the GC syrup also was well accepted. The insulin concentrations at 120 min correlated significantly between tube OGT and GC pellets (r = .717; P < .001) or GC syrup (r = .913; P < .001). The new GC syrup and GC pellets discriminate between healthy and ID horses. CONCLUSIONS AND CLINICAL SIGNIFICANCE: The GC pellets (DysChEq)™ and GC syrup can be used as palatable and well-accepted oral GC tests for assessment of ID in horses.

Habituation and short-term repeatability of thermal testing in healthy human subjects and patients with chronic non-neuropathic pain.

We investigated habituation effects during thermal quantitative sensory testing (tQST) using 8 repetitive measurements for thermal detection and pain thresholds. The same measurements were repeated two days later. 39 healthy subjects and 36 patients with chronic non-neuropathic pain syndromes (migraine, tension-type headache, non-radicular back pain) were enrolled. The pain intensity was assessed using an 11-point (0-10) numerical rating scale. Measurements correlated significantly over the two days in both groups (r=0.41...0.62). Warm detection (WDT) and heat pain threshold (HPT) revealed no significant differences over these days. Cold detection (CDT) and pain thresholds (CPT) showed significant differences but these were small compared to the range of normal variability (CDTDelta -0.28 degrees C; CPTDelta 1.51 degrees C). On both days, WDT showed no habituation during measurements. Although there was a small difference in CDT and CPT between first and second measurement, there was no habituation beyond the second stimuli. In contrast, HPT significantly increased between first and sixth stimuli, indicating pronounced habituation. Average HPT of first to third measurement was significantly lower than HPT of the fourth to sixth assessment (45.9 degrees C; 47.7 degrees C) with a good day-to-day repeatability. Repeatability and habituation was identical in both groups. Ongoing pain intensity in the patient groups correlated significantly with CDT/WDT but not with CPT, HPT, indicating that ongoing pain might suppress the sensitivity to non-painful stimuli. In summary, tQST proved a reliable diagnostic tool for clinical practice. Day-to-day differences were small but without clinical relevance. Habituation was most pronounced for HPT, probably due to peripheral fatigue of the receptors.

Randomised controlled comparison of the Health Survey Short Form (SF-12) and the Graded Chronic Pain Scale (GCPS) in telephone interviews versus self-administered questionnaires. Are the results equivalent?

BACKGROUND: The most commonly used survey methods are self-administered questionnaires, telephone interviews, and a mixture of both. But until now evidence out of randomised controlled trials as to whether patient responses differ depending on the survey mode is lacking. Therefore this study assessed whether patient responses to surveys depend on the mode of survey administration. The comparison was between mailed, self-administered questionnaires and telephone interviews. METHODS: A four-armed, randomised controlled two-period change-over design. Each patient responded to the same survey twice, once in written form and once by telephone interview, separated by at least a fortnight. The study was conducted in 2003/2004 in Germany. 1087 patients taking part in the German Acupuncture Trials (GERAC cohort study), who agreed to participate in a survey after completing acupuncture treatment from an acupuncture-certified family physician for headache, were randomised. Of these, 823 (664 women) from the ages of 18 to 83 (mean 51.7) completed both parts of the study. The main outcome measure was the comparison of the scores on the 12-Item Short-Form Health Survey (SF-12) and the Graded Chronic Pain Scale (GCPS) questionnaire for the two survey modes. RESULTS: Computer-aided telephone interviews (CATI) resulted in significantly fewer missing data (0.5%) than did mailed questionnaires (2.8%; p < 0.001). The analysis of equivalence revealed a difference between the survey modes only for the SF-12 mental scales. On average, reported mental status score was 3.5 score points (2.9 to 4.0) lower on the self-administered questionnaire compared to the telephone interview. The order of administration affected results. Patients who responded to the telephone interview first reported better mental health in the subsequent paper questionnaire (mean difference 2.8 score points) compared to those who responded to the paper questionnaire first (mean difference 4.1 score points). CONCLUSION: Despite the comparatively high cost of telephone interviews, they offer clear advantages over mailed self-administered questionnaires as regards completeness of data. Only items concerning mental status were dependent on the survey mode and sequence of administration. Items on physical status were not affected. Normative data for standardized telephone questionnaires could contribute to a better comparability with the results of the corresponding standardized paper questionnaires.

Validation and reliability of the German version of the Chronic Pain Grade questionnaire in primary care back pain patients.

In 1992 Von Korff and his co-workers developed a simple, brief questionnaire to assess the severity of chronic pain problems, the Chronic Pain Grade (CPG). The present study was conducted to analyse the psychometric properties of the translated German version of the CPG within a population of primary care back pain patients (n=130). Factor analysis yielded two factors which accounted for 72% of the variance of the questionnaire. The first factor 'Disability Score' (53.56% of the variance) revealed a good internal consistency (alpha=.88), the internal consistency of the second factor 'Characteristic Pain Intensity' was moderate (alpha=.68). The reliability of the whole instrument was good (alpha=.82). The CPG and its subscales show moderate to high relations with other instruments assessing the patient's disability (FFbH-R, Pain Disability Index PDI). Additionally weak to moderate but significant correlations were found between the CPG and other measures of grading and staging chronic pain (MPSS, RGS). Further, positive correlations between the CPG and both, the frequency of doctor visits and the frequent use of pain medication have been seen. The reported findings suggest, that the German version of the CPG is a reliable, valid and useful instrument if a brief, simple method of grading the severity of chronic pain is needed. The German version leads to a better comparability between German and English language studies and facilitates an international collaboration in this field of research.