LAUSR

Diabetes in elderly people is one of the main problems for our Public Health System today. Aging is causing a marked increase in the pandemic of diabetes and its prevalence in Spain for men and women older than 75 years-old is greater than 20%.1 We know that the therapeutic strategies and targets should be individualized in these patients but scientific evidence to support the most appropriate treatment is scarce.2--3 Metformin is the firstline agent and recent studies have indicated that it may be used safely in patients with estimated glomerular filtration rate (eGFR) ≥30 ml/min/1.73 m2. However, metformin is contraindicated in patients with advanced renal insufficiency. Sulfonylureas are associated with hypoglycemia and should be used with caution in patients with increased susceptibility.4--5 Ruiz-Tamallo et al. observed that a significant proportion of patients with eGFR <30 ml/min/1.73 m2 were on metformin or sulfonylureas treatment.6 The aim of our study was to know if the use of metformin and sulfonylureas were lower in patients ≥75 years-old with eGFR <45 ml/min/1.73 m2 and determine the prevalence of patients ≥75 years-old who are in treatment with metformin or sulfonylureas that have had eGFR <30 ml/min/1.73 m2 or without eGFR within the last year. From January 2017 to April 2017, we identified in our pharmacological prescription program, 1183 patients ≥75 years-old who were taking pharmacological treatment for diabetes (insulin and no insulin). These patients live among the three basic health areas located in the southeast of Castilla-La Mancha which attend a total of 41992 inhabitants. 70.4% of them were treated with metformin and 14% with sulfonylureas (13 patients were on gliblenclamide treatment). We analyzed a randomly selected sample of 295 patients (calculated to have enough statistical power) and the following variables were collected: age (years), sex (male or female), pharmacological treatment for diabetes (metformin, sulfonylureas, glinides, thiazolidinediones, DPP-4 inhibitors, GLP-1 receptor agonist, SGLT-2 inhibitors and insulin), and the last blood analysis with A1c and eGFR in the previous year. Data were analyzed with the use of G-Stat 2.0 software. Qualitative variables were expressed as an absolute and relative frequency. Quantitative variables were expressed as a mean and standard deviation (SD). The Chi-square test was used to compare proportions of use of metformin or sulfonylureas between two groups (eGFR <45 ml/min/1.73 m2 vs. eGFR ≥45 ml/min/1.73 m2). A p value <0.05 was considered statistically significant. The mean age was 82.7 years (SD: 5.1) and 106 patients (35.9%) were 85 years of age or older. 173 patients (58.6%) were women. 220 patients (74.6%) were on metformin, 39 (13.2%) on sulfonylureas, 18 (6.1%) on glinides and 99 (33.6%) on DPP-4 inhibitors. Only 1 patient was treated with GLP-1 receptor agonist and 9 with SGLT-2 inhibitors. 45 patients Table 1 Estimated glomerular filtration rate (eGFR) and metformin or sulfonylureas treatment.