Long-Term Influence of Locus of Control and Quality of Life on Metabolic Profile in Elderly Subjects with Type 2 Diabetes

Background: The Locus of Control (LOC) is a mental disposition indicating the individuals' belief that disease-related outcomes are under their own control (Internal), dependent on others (External), or dependent on chance (Chance). Quality of Life (QoL) and LOC may have complex effects on self-care activities and diabetes management in subjects with type 2 diabetes (T2D). The aim of the present study was to evaluate the predictive role of LOC and QoL scores on metabolic control in elderly T2D outpatients, secondly evaluating potential gender differences. Methods: An extensive set of questionnaires was administered to a group of consecutive elderly T2D outpatients on oral glucose-lowering drugs attending a single diabetes center. Personal and clinical variables were analyzed at baseline (between 1 February and 31 March 2015) and after 6 years of follow-up. Results: At baseline, study participants showed an overall good metabolic control. Diabetes Specific Quality of Life (DSQoL) scores indicated an overall good QoL in both genders, with a higher DSQoL satisfaction score in women. Both genders presented higher scores in the LOC-Internal domain, with men reaching higher scores in the LOC-External domain than women. At the 6-years follow-up, subjects with baseline higher LOC-External score presented better metabolic outcome. In the regression analysis, LOC-External score was an independent predictor of good metabolic control maintenance, but this result was only statistically significant in men. Conclusions: LOC scores may influence long-term glycemic control in elderly T2D patients on oral glucose-lowering drugs.