Glucose tolerance and physical activity level in people with spinal cord injury

Abstract

Study design: Cross-sectional, observational study. Objectives: To evaluate the associations of physical activity and neurological lesion level with glucose tolerance in people with spinal cord injury (SCI). Setting: New South Wales, Australia. Methods: Twenty-five people (5 women, 20 men) with SCI (46 months post-injury) aged between 18 and 65 years were recruited. Exclusion criteria included known coronary heart disease, stroke or diabetes. Participants underwent an oral glucose tolerance test. Fasting and 2-h plasma glucose concentrations were classified according to the World Health Organization categories of glycemia. Participants also completed the Physical Activity Scale for Individuals with Physical Disabilities and mean MET-hours day À1 was calculated. Associations with the 2-h plasma glucose concentration were calculated through multiple and stepwise regressions. Results: Participants presented with complete or incomplete tetraplegia (n ¼ 11 TETRA) or complete or incomplete paraplegia (n ¼ 14 PARA) with neurological lesion levels ranging from C3/4 to T12. Mean 2-h plasma glucose was 7.13 ± 2.32 mmol l À1 . Nine participants had disordered glycemia (n ¼ 6 TETRA; n ¼ 3 PARA) and the remaining participants had normal glucose tolerance. Those participants with normal glucose tolerance participated in more moderate-vigorous and strength exercise and undertook more non-exercise-related mobility than those with disordered glycemia. Physical activity and age, but not lesion level were independent determinants of 2-h plasma glucose concentration (r ¼ 0.683, P ¼ 0.001), explaining 47% of the variance. Conclusion: Physical activity level is independently associated with glucose tolerance in people with SCI. Non-exercise activity may also be important for maintaining normal glycemia.

Insulin resistance in tetraplegia but not in mid-thoracic paraplegia: is the mid-thoracic spinal cord involved in glucose regulation?

“…Among them, the smaller muscle mass reduction, as suggested in an earlier publication, 1 the younger mean age that was found to be associated with lower peak serum glucose concentration after SCI, 1 the higher activity level that was found to be related to glucose tolerance after SCI 20 and a possible lower level of stress. These imply that various mechanisms can be attributed to IR in SCI, and the mechanism suggested in this paper is only one of the hypotheses deserving further investigation.…”

Contributors to Metabolic Disease Risk Following Spinal Cord Injury

“…Across studies, a relatively consistent metabolic profile of elevated circulating glucose, insulin resistance and hyperlipidemia is present in subjects with SCI [4;6;10–13]. Explanatory variables including a loss of lean mass (particularly skeletal muscle), reduced physical activity, excess energy intake relative to need, and systemic compensatory responses related to impaired autonomic function, mediated through the above mentioned variables, have been previously studied [14;15]. Although data show reduced energy expenditure in SCI subjects relative to uninjured controls [14;16;17], controlling for the difference in lean body mass and decreased physical activity does not fully account for the decline in energy expenditure and increased disease risk [17], particularly for those individuals with injuries to higher anatomic levels of the spine [5;15;17–20].…”

“…Explanatory variables including a loss of lean mass (particularly skeletal muscle), reduced physical activity, excess energy intake relative to need, and systemic compensatory responses related to impaired autonomic function, mediated through the above mentioned variables, have been previously studied [14;15]. Although data show reduced energy expenditure in SCI subjects relative to uninjured controls [14;16;17], controlling for the difference in lean body mass and decreased physical activity does not fully account for the decline in energy expenditure and increased disease risk [17], particularly for those individuals with injuries to higher anatomic levels of the spine [5;15;17–20]. While multiple factors may contribute to this differential metabolic-related disease risk in subjects with SCI, this review highlights observations related to the anatomic level of injury, alterations in body composition, skeletal muscle biology, energy expenditure, metabolic substrate metabolism, sympathetic nervous system function, and a potential role for brown adipose tissue in these metabolic-disease risk relationships.…”

“…Metabolic impairment and disease risk are greater in individuals with high-level injuries [15;18;21]. Individuals with high-level injuries who have greater neurologic impairment present with significantly lower glucose tolerance, greater insulin resistance and impaired lipid profiles when compared with both uninjured controls and low-level injury cases [4;6;11;16].…”

Benefits of an exercise wellness program after spinal cord injury

“…there is growing evidence to support the benefits of exercise and leisure time physical activity on the physiologic [9][10][11][12][13] and overall psychosocial 11,[14][15][16][17][18][19][20][21] function of individuals with SCI. Despite this, surveys have noted low participation rates in exercise and leisure time physical activity compared to the general population.…”