[Drug consumption in diabetes mellitus (III). Trends of hypoglycemic agents use and consumption in Tarragona, Catalonia, and Spain (1988- 1991). Group for the Study of Diabetes in Tarragona].

Background: To analyze the evolution of the use of drugs in diabetes, the consumption of hypoglycemic medication in the province of Tarragona, the autonomic community of Catalonia and Spain as a whole, was studied. A qualitative evaluation of the tendencies of prescription, as an indirect index of quality in the health care to diabetics was performed.
Methods: The sales of oral hypoglycemic medication (OH) and insulin (INS) were accounted for in the study environment between 1988-1991. To make consumption uniform a standardized unit of measure was used with defined daily doses (DDD)/1,000 inhabitants/day (Drug Utilization Research Group) of the different groups of drugs. Total consumption was obtained by a primary data source (Intercontinental Medical Statistics), and periodically compared with a secondary source (registry of public prescriptions within Tarragona).
Results: A progressive increase in the consumption of hypoglycemic drugs was observed: 16.1 to 21.2 DDD/1,000 inhabitants/day (31%) in Spain; 17.7 to 19.8 (12%) in Catalonia and 19 to 23 (21%) in Tarragona. The increase in consumption of INS in Tarragona (43%) was greater than that of OH (12%). In Catalonia, it was much greater (INS: 23%, OH: 7%) and was parallel in Spain (36% and 30%, respectively). The OH/INS index decreased in Catalonia and Tarragona (1.3 and 1.9 in 1991) and remained practically constant (2.3-2.4) in Spain. A global decrease was produced in the consumption of slow insulins with a significant increase in intermediate, premixed and fast insulins. A growing increase in glibenclamide much greater than the remaining sulphonylureas was seen, in addition there was a persistent and low use (less than 1 DDD/100 inhabitants/day) of biguanides. Significative variations of medication consumption were registered according to the territory analyzed.
Conclusions: From 1988 to 1991 there has been an increase in the use of hypoglycemic drugs. The use of oral hypoglycemics has remained constant in relation to insulins in Spain and in Catalonia and, more so in Tarragona, there is a progressive inclination to the use of insulin. The evolution of consumption suggests important asymmetry in the quality of health care and denotes progression in the global educative offer to diabetics.