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Male and female obligate runners and anorexia nervosa patients were compared to determine whether they have psychological and physiological similarities. The study tested the hypotheses that male runners, female runners and anorexia nervosa patients would have similar psychological profiles and abnormal body composition as measured by fat content. It was also hypothesized that male and female runners would be much fitter than anorexia nervosa patients. The study found few psychological or physiological similarities among the three groups.

Abstract Background Streptozotocin-induced diabetes (STZ-D) in rats has been associated with carnitine deficiency, bradycardia and left ventricular enlargement. Aim The purpose of this study was to determine whether oral carnitine supplementation would normalize carnitine levels and cardiac function in STZ-D rats. Methods Wistar rats (48) were made hyperglycemic by STZ at 26 weeks of age. Same age normal Wistar rats (24) were used for comparison. Echocardiograms were performed at baseline 2, 6, 10, and 18 weeks after STZ administration in all animals. HbA1c, serum carnitine and free fatty acids (FFA) were measured at the same times. Since STZ-D rats become carnitine deficient, 15 STZ-D rats received supplemental oral carnitine for 16 weeks. Results The heart rates for the STZ-D rats (290 ± 19 bpm) were less than control rats (324 ± 20 bpm) (p < 0.05). After 4 weeks of oral carnitine supplementation, the serum carnitine and heart rates of the STZ-D rats returned to normal. Dobutamine stress increased the heart rates of all study animals, but the increase in STZ-D rats (141 ± 8 bpm) was greater than controls (79 ± 8 bpm) (p < 0.05). The heart rates of STZ-D rats given oral carnitine, however, were no different than controls (94 ± 9 bpm). The left ventricular mass/body weight ratio (LVM/BW) in the diabetic animals (2.7 ± 0.5) was greater than control animals (2.2 ± 0.3) (p < 0.05) after 18 weeks of diabetes. In contrast, the LVM/BW (2.3 ± .2) of the STZ-D animals receiving supplemental carnitine was the same as the control animals at 18 weeks. Conclusion Thus, supplemental oral carnitine in STZ-D rats normalized serum carnitine, heart rate regulation and left ventricular size. These findings suggest a metabolic mechanism for the cardiac dysfunction noted in this diabetic animal model.

Objectives: To investigate glucose levels as a risk factor for unrecognized myocardial infarctions (UMIs). Design: Cohort Setting: Cardiovascular Health Study. Participants: Individuals aged 65 and older with fasting glucose measurements (N=4,355; normal fasting glucose (NFG), n = 2,041; impaired fasting glucose (IFG), n = 1,706; DM: n = 608; 40% male, 84% white, mean age 72.4 ± 5.6). Measurements: The relationship between glucose levels and UMI was examined. Participants with prior coronary heart disease (CHD) or UMI on initial electrocardiography were excluded. Using Minnesota codes, UMI was identified according to the presence of pathological Q‐waves or minor Q‐waves with ST‐T abnormalities. Crude and adjusted hazard ratios (HRs) were calculated. Analyses were adjusted for age, sex, body mass index (BMI), hypertension, antihypertensive and lipid‐lowering medication use, total cholesterol, high‐density lipoprotein cholesterol, and smoking status. Results: Over a mean follow‐up of 6 years, there were 459 incident UMIs (NFG, n=202; IFG, n=183; DM, n=74). Participants with IFG were slightly more likely than those with NFG to experience a UMI (hazard ratio (HR)=1.11, 95% confidence interval (CI)=0.91–1.36, p = .30), and those with DM were more likely than those with NFG to experience a UMI (HR=1.65, 95% CI=1.25–2.13, p < .001). After adjustment HR for UMI in IFG those with IFG were no more likely than those with NFG to experience a UMI (HR=1.01, 95% CI=0.82–1.24, p = .93), whereas those with DM were more likely than those with NFG to experience a UMI (HR=1.37, 95% CI=1.02–1.81, p = .03). The 2‐hour oral glucose tolerance test was not statistically significantly associated with UMI. Conclusion: Fasting glucose status, particularly in the diabetic range, forecasted UMI during 6 years of follow‐up in elderly adults. Further studies are needed to clarify the level of glucose at which risk is greater. J Am Geriatr Soc 67:43–49, 2019. [ABSTRACT FROM AUTHOR]