Psychological factors and metabolic control in insulin-dependent diabetes mellitus

Abstract: This doctoral thesis consists of six studies concerning persons with insulin dependent diabetes mellitus (IDDM). The first two deal with relationships between life events, social support and metabolic control (HbA1C) over a two year period. For the female subjects, results obtained for this period were inconsistent. For the male group, negative life events and poor social support were found to be related to poor HbA1C values during the entire period. The results are discussed in terms of possible gender differences in stress responses, social support, and coping strategies. The third study investigated two groups of IDDM subject over a two-year period, one of them showing a ”major” and the other a ”minor” discrepancy between how they retrospectively perceived their quality of life to have changed and the change of their current quality of life assessed before and after the study period. Those exhibiting a ”major” discrepancy reported greater retrospective quality of life improvement, higher quality of life, greater well-being and a lesser ocurrence of negative life events than those with a ”minor” discrepancy did, despite their exhibiting poorer blood glucose values and a higher prevalence of incipient nephropathy. The results are discussed in terms of possible psychological defense strategies. The fourth study aimed at examining changes in quality of life, negative life events and metabolic control in IDDM subjects during a five year period beginning one year after their transition to multiple injection therapy with the insulin pen. For the group as a whole, quality of life was found to change only moderately, whereas metabolic control deteriorated significantly over time. However, two subgroups clearly differing in assessed quality of life, in the reporting of negative life events and in metabolic control patterns could be distinguished. The results are discussed in terms of the clinical suitability of a multiple injection regimen using the insulin pen. The fifth study concerned the relevance of different diabetes-related locus of control belief patterns to metabolic control. As hypothesized, subjects who exhibited a strong belief in internal control, in conjunction with a low degree of belief in control by chance, showed better metabolic control than those who displayed the opposite locus of control pattern. The results are discussed in terms of adaptation to the disease and in planning treatment of IDDM patients. The sixth study, finally, explored relationships between age, severe long-term complications and diabetes locus of control beliefs. No relationships between complications, age, and internal control beliefs were obtained. However, subjects with severe long-term complications displayed a stronger belief in chance than those without such complications. Also, older subjects expressed a stronger belief in control by powerful others and in control by chance than younger subjects did. Finally, subjects between 38 and 50 years of age with severe complications displayed stronger beliefs in powerful others than those within their age-group without such complications. The results are discussed in terms of how difficulties and demands that persons with diabetes face can interplay with locus of control beliefs.