Factor analysis of the metabolic syndrome in spinal cord-injured men

Disturbances of carbohydrate and lipid metabolism in men with spinal cord injury are common, but poorly defined. Clustering of recognized risk factors for obesity and disorders of carbohydrate and lipid metabolism are characteristic of the metabolic syndrome. The purpose of this study was to investigate the presence of metabolic syndrome using modifications of the World Health Organization (WHO) definition and including total physical activity levels (minutes/week), in a group of active males with spinal cord injury who were carefully matched for age, height, and weight with active able-bodied males. Factor analysis is used widely to explore factors of the metabolic syndrome. This technique was used in this study of 20 spinal cord-injured (SCI) men and 20 able-bodied controls, matched for age, height, and weight. Three-factor models, each reflecting a different aspect of the metabolic syndrome, were identified for both study groups. The average communality score for the SCI group was 0.8 and 0.7 for the control group. For the SCI group, factor 1 reflected an interaction between adiposity measures, physical activity, and postload insulin and glucose, factor 2 was reflective of dyslipidemia, while factor 3 revealed an interaction between fasting levels of insulin and glucose. In the control group, factor 1 reflected an association between the adiposity measures and physical activity, factor 2 was reflective of postload glycemic control, with factor 3 reflecting an interaction between fasting insulin and dyslipidemia. By summation of the total variance of each factor, the 3-factor models explained 80% and 69% of the variance in the original 9 variables examined in the SCI and control groups, respectively. In summary, while the WHO definition for the metabolic syndrome appears suitable for use in identifying the incidence of this syndrome in SCI men, some modification of anthropometric and lipid measures may be required.