Objective
To determine the socio-demographic, psychologic, hematologic, or other relevant factors associated with hand grip strength in Korean farmers.
Methods
A total of 528 healthy Korean farmers were enrolled. Hand grip strength was measured in both hands using a hydraulic dynamometer. Socio-demographic characteristics were assessed and anthropometric measurements were obtained. Psycho-cognitive measurements such as sleep quality (Pittsburgh Sleep Quality Index) and Go/No-Go test response time were conducted. In addition to physical measurements, serologic parameters including insulin-like growth factor 1 were measured. The factors associated with hand grip strength were analyzed using multiple linear regression analysis after adjusting for age, height, and weight.
Results
The mean hand grip strength was associated with the Pittsburgh Sleep Quality Index total score (β=-0.12, p=0.01), the Go/No-Go test response time (β=-0.18, p=0.001), vitamin D (β=0.12, p=0.02), and insulin-like growth factor 1 levels (β=0.1, p=0.045). In female farmers, hand grip strength was only associated with the Pittsburgh Sleep Quality Index total score (β=-0.32, p<0.001).
Conclusion
The results of this study demonstrate that hand grip strength was associated with sleep quality and attention in Korean farmers.

Citations

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Objective
To investigate the change of blood glucose and cortisol levels after three consecutive epidural steroid injections Method: Fifteen patients with low back pain and radiating pain were included. Three consecutive epidural injections were performed weekly. The serum glucose, insulin and cortisol levels were measured 30 minutes before the 1st injection and at 24 hours and l week after each injection. Results: There were significant changes in the result of glucose and insulin levels at 24 hours after each injection (p＜0.05), but no signigicant changes at 1 week compared with pre-injection level. The cortisol level significantly decreased at 24 hours after 1st injection and did not return to pre-injection level at 1 week after 1st injection (p＜0.05). There were no further increases in the glucose and insulin levels and no further decrease in the cortisol level after each of the three consecutive injections. Conclusion: Three consecutive epidural injections at 1 week interval seems to be as safe procedure. But significant suppression of cortisol kept on for 1 week, so it should be taken into account when patients with previous epidural injection undergo major stress. (J Korean Acad Rehab Med 2006; 30: 590-594)

OBJECTIVE
To compare the Madopar(R) (Levodopa Benserazide) test with Insulin Tolerance Test (ITT) as a provocation test for growth hormone (GH). METHOD: One hundred eighty-seven subjects who had not organic disease such as hypothalamic-pituitary disease were studied. Seventy-one subjects underwent an ITT by injection of 0.1 U/kg of regular insulin and blood samples for GH assay were taken at 0, 30, 60 and 120 minutes. One hundred sixteen subjects underwent a Madopar(R) test by administration of Madopar(R) and blood samples for GH assay were taken at 0, 60, 120 and 180 minutes. RESULTS: The GH mean peak response in ITT was significantly higher than that of the Madopar(R) test. Below 50 years, 18 of ITT and 24 of Madopar(R) test showd a GH peak response of less than 5 ng/ml. Above 50 years, 14 of ITT and 53 of Madopar(R) test showd a GH peak response of less than 5 ng/ml. CONCLUSION: The results suggested that the GH response to the Madopar(R) test was much less than that of the ITT. The Madopar(R) test was limited in diagnosis of the adult GH deficiency in normal adults.

Objective
This study was performed to determine the relations of glycosylated hemoglobin (HbA1c) and parameters of nerve conduction study (NCS) in diabetic peripheral polyneuropathy patients.

Method: Prospectively, total 40 patients with non-insulin dependent diabetes mellitus were included in the study. NCS was performed on median, ulnar, posterior tibial, deep peroneal, superficial peroneal, and sural nerves. Distal latency and conduction velocity (CV) of compound muscle action potential (CMAP), distal latency and amplitude of sensory nerve action potential (SNAP) were used as parameters of NCS. Multiple linear regression analysis were used to analyze the relations of HbA1c and parameters of NCS, after adjustment for age, height, weight, and disease duration of diabetes mellitus.

Results: HbA1c level had an inverse relation to CV of median motor nerve (β=⁣1.272, p＜0.01), ulnar motor nerve (β=⁣1.287, p＜0.01), posterior tibial nerve (β=⁣0.982, p＜0.05), and deep peroneal nerve (β=⁣1.449, p＜0.05).

Conclusion: This study indicates that HbA1c level was inversely related to motor nerve CV, and that sustained hyperglycemia may be involved in demyelination of motor nerves. Analysis of motor nerve CV related to HbA1c is expected to be useful in the follow-up or efficacy study of diabetes mellitus neuropathy as baseline data. (J Korean Acad Rehab Med 2003; 27: 80-84)