THE INFLUENCE OF CLINICAL PRESENTATION AND METABOLIC CONTROL OF INSULIN-DEPENDENT DIABETES IN THE EVOLUTION OF RESIDUAL INSULIN-SECRETION -A PROSPECTIVE-STUDY AT 5 YEARS

BACKGROUND: TO study the influence of clinical, metabolic and immunolo gical parameters during the first years of the evolution of insulin-de pendent diabetes mellitus (IDDM) on the long-term residual insulin sec retion [IS). PATIENTS ANO METHODS: 186 IDDM subjects diagnosed from 19 86 to 1993 were included; 135 subjects have completed a two year follo w-up, and 57 have completed a five year follow-up. The influence of in dividual characteristics at diagnosis (age, sex, clinical presentation , iset-cell antibodies) and during the first two years of follow-up (I S, metabolic control) on IS at five years was evaluated by multiple li near regression. Differences between groups were evaluated by non-para metric tests. RESULTS: 18 patients had a significant insulin secretion at five years (post-glucagon C-peptide equal to or greater than 0.15 nmol/l). They showed minor significant differences in sex (77.7 vs 48. 7% of males, p = 0.03), duration of symptoms (12.9 vs 7.2 weeks, p = 0 .01), ketoacidosis at diagnosis (23.3 vs 46.1%, p = 0.07) and ICA posi tivity at diagnosis (41.1 vs 69.4%, p = 0.05). They also had a better metabolic control (8.8 vs 10.8% of HbA(1), p < 0.001) with Iss insulin (0.48 vs 0.71 Ul/kg, p < 0.001) during the first two years of evoluti on. Initial IS was similar, but differences became significant at 6 mo nths. In the multivariate analysis, only metabolic control during the second year of evolution (p = 0.008), ketoacidosis at diagnosis (p = 0 .026) and sex [p = 0.026) had an independent influence on IS at five y ears. A more intensified therapeutic approach introduced in 1990 induc ed a better metabolic control and higher IS during the first years of follow-up. CONCLUSION: The absence of ketoacidosis at diagnosis and a good metabolic control during the first two years can have a positive influence in the long-term preservation of IS in IDDM patients.