Residual insulin secretion at diagnosis of type 1 diabetes is independently associated with both, age of onset and HLA genotype.

BACKGROUND: We investigated whether residual insulin secretion and metabolic derangement at diagnosis of type 1 diabetes (T1DM) are influenced by human leukocyte antigens (HLA) class II genes. METHODS: Eight hundred and seventy-one T1DM consecutive Caucasian patients were typed for HLA class II genes. In 300 of these patients, glycated haemoglobin, insulin requirement, baseline C-peptide and body mass index (BMI) Z-score were measured at clinical diagnosis. The effect of the HLA genotypes on the quantitative variables was investigated using multiple linear regression. The beta coefficient regression of the age at onset and HLA genotypes were standardized to compare their specific importance for C-peptide levels. RESULTS: The HLA genotypes were divided in high-, moderate- and low-risk categories. The frequency of high-risk genotype, DRB1*03-DQB1*0201/DRB1*04-DQB1*0302, decreased with increasing age of onset (p < 0.0001, chi(2) linear trend). The presence of the high-risk genotype was independently associated with lower C-peptide levels at diagnosis (p = 0.002). In the regression analysis of C-peptide levels, the standardized beta coefficient for age of onset and high risk compared to low-risk genotypes showed similar results (0.27 and 0.24 respectively). There was a positive association between age of onset and C-peptide (p < 0.0001) and a negative association between age of onset and insulin requirement (p < 0.0001). CONCLUSIONS: The degree of beta-cell destruction at diagnosis of T1DM is independently associated with both, age of onset and HLA genotypes, the two variables exert a similar quantitative effect on residual beta-cell function at diagnosis.

Stapes surgery in relation to age.

This prospective study aims to evaluate the efficacy of stapedotomy in relation to age. Eighty-four ears of 82 consecutive patients who underwent stapedotomy were studied. Patients were divided into five groups according to their age. In each patient, we evaluated the pre- and postoperative auditory thresholds, according to the Committee on Hearing and Equilibrium of the American Academy of Otolaryngology - Head and Neck Surgery guidelines. Statistically significant (P < 0.05) differences between the pre- and postoperative air conduction thresholds were observed in all groups. Statistically significant reductions of air-bone gap were observed at lower-medium frequencies (250, 500 and 1000 Hz) in the elderly as well as in the younger patients. We did not find a higher susceptibility of the inner ear to surgical trauma in the elderly in comparison to the younger patients. Our data show that stapedotomy results in older adults are comparable to those obtained in the younger, without an increased incidence of complications.