Tailoring of glucose lowering therapy in older patients with diabetes mellitus.

INTRODUCTION. Little is known on insulin sensitivity and secretion in older patients with type 2 diabetes mellitus (DM2), a heterogeneous group of patients. Differences might indicate the need for tailored glucose lowering therapy. METHODS. Cross-sectional study of 210 consecutive older (≥ 75 years)patients followed for DM2 at the outpatient diabetes clinic of an academic hospital. DM2 was classified as habitual-onset diabetes (HODM2) when diagnosed < 65 years or elderly-onset diabetes (EODM2) when diagnosed ≥ 65 years. Insulin sensitivity and β-cell function were assessed by HOMA modeling. Statistical significance (p<0.05) of differences was assessed using Student’s t-test, Welch’s test or Fisher’s Exact test. RESULTS. Patients with EODM2 (n=88; 82.6 ± 5 years), as compared to HODM2 (n=122; 81.2 ± 6 years), had a shorter history of DM2 (10 ± 5 vs. 26 ± 10 years). Both groups were not different in terms of cardiovascular risk factors and DM2-related complications, except at the microvascular level (EODM2 vs. HODM2: 45 vs. 72%). EODM2 significantly differed from HODM2 in 4 anthropometric and metabolic characteristics: lower BMI (26.6 vs. 28.2 kg/m2), lower prevalence of obesity (18 vs. 27%), higher insulin sensitivity (66 vs. 53%) and higher residual β-cell secretion (68 vs. 52%). Although HbA1c was similar in both groups (7.31 vs. 7.62%), HbA1c < 7% was more frequently observed in EODM2 patients than in HODM2 ones (49 vs. 37%). EODM2 patients, as compared to HODM2 ones, received significantly lighter antidiabetic regimens, specifically oral ones (bi- or tri-therapies: 28% vs. 59%) and insulin (32 vs. 66%, p