[The long-term stability of reactive strips for capillary blood glucose preserved at between 2 and 5 degrees C]. / Estabilidad a largo plazo de las tiras reactivas de glucemia capilar conservadas entre 2 y 5 grados C.

OBJECTIVE: To assess the stability of the reactive strips for capillary glycemia, preserved between 2 and 5 degrees C, and at ambient temperature, during 8 weeks. DESIGN: Transversal descriptive study. SETTING: Health Center "V Centenario" of San Sebastián de los Reyes. PATIENTS AND OTHER PARTICIPANTS: 322 strips were obtained, 31 were underrated because they could not read the orderly days, of the 291 remaining, 159 were kept in the refrigerator between 2 and 5 degrees C, and 132 were kept at ambient temperature, preserved to the light. MEASUREMENTS AND MAIN RESULTS: All the strips were type "BM-test-glycemia 24 hours, and the weeks 1 to 8. At ambient temperature the strips lose the 5% of their basal value, and the 23 and 32% in the first and second weeks respectively (p < 0.001). The strips kept in refrigerator have a rise at 24 hours, with regard to basal value of 7% (p < 0.001). Starting from this moment, a gradual fall of the mean value of the glycemia is produced, significant differences were not found in the second week. After 8 weeks, a mean loss of 10% of the strip value is noticed. CONCLUSIONS: The fall of the strip value, preserved in refrigerator is not clinically very important, an acceptable control of the diabetic patient can be obtained by delayed reading, even 8 weeks, of reactive strips that patients can keep in their refrigerators.