Trends in the use of lipid-lowering drugs by outpatients with diabetes in Taiwan, 1997-2003

PURPOSE

To analyze recent trends in LLD use by outpatients with diabetes in Taiwan over a 7-year period and to see whether the trends are consistent with clinical trial outcomes and published guidelines.

METHODS

A cross-sectional survey was implemented using the National Health Insurance Research Database between January 1997 and December 2003. Adult outpatients who had diagnoses of diabetes and dyslipidemia and who had concurrent antidiabetic drug and LLD claim were identified. The prescribing trends were described in terms of the prescribing rates and patterns of LLDs in each study year.

RESULTS

Between 1997 and 2000, fibrates were the most widely prescribed major class of LLDs, while the rates showed a significant decline over time. The proportions of statin use increased 3.3-fold from 20.8% of all LLDs in 1997 to 69.0% in 2003. With the continuous increase in the use of statins, by 2001, they replaced fibrates as the most heavily used LLDs. Monotherapy was the most prominent prescribing pattern comprising 98.1% and 98.3% of all LLD prescriptions in 1997 and 2003, respectively. Among patients with diabetic dyslipidemia plus CHD, the use of statins increased almost threefold instead of a large reduction in the percentage with non-statin class.

CONCLUSIONS

The prescribing rates of LLDs shifted from the fibrates to statins, especially in newer statin. The majority of patients were maintained on monotherapy. These findings may imply that management of hyperlipidemia in patients with diabetes had a positive trend towards recent clinical trial outcomes and guideline's recommendation.

Theoretical exposure of chronically treated patients to lipid lowering agents

PURPOSE

The objective was to analyse the exposure to lipid lowering agents (LLA) using the databases of health insurance companies and to appraise its concordance with the findings of evidence based medicine.

METHODS

Three health insurance companies' prescription based databases were analysed in the years 1997-2000. All inhabitants in the Czech Republic (CR) have to be insured. The insured person with a recorded prescription for LLA in the year of interest was defined as a patient, the insured person with a recorded prescription for LLA in the years bordering the year of interest was defined as a chronically treated patient. In the year of interest the percentage of chronically treated patients without LLA medication, with 'very low' (<122 defined daily doses (DDD)/year), 'low' (122-243 DDD/year) and 'adequate' (>243 DDD/year) consumption was determined.

RESULTS

During the observed period the total consumption of LLA increased among 450 000 inhabitants twice (by 109.6%) to 24.8 DDD/1000 inhabitants/day. In 2000 the rate of the consumption of statins and fibrates represented 34.2 and 65.6% respectively. In 1998 33.5% and in 1999 41.0% of the chronically treated patients occurred in the 'adequate' consumption group.

CONCLUSIONS

The signals of inappropriate drug treatment such as the preferred use of fibrates and low doses of LLA prescribed to the Czech population were identified. Conversely, the increasing proportion of the chronically treated patients belonging to the group with the 'adequate' consumption could be considered as a positive signal.

Time trends in lipid lowering drug use in The Netherlands. Has the backlog of candidates for treatment been eliminated?

AIMS

To assess time trends in lipid lowering drug use in The Netherlands.

METHODS

Data were obtained from the PHARMO-database, comprising pharmacy records of approximately 300 000 people in The Netherlands. In the period from 1991-98, we estimated prevalence of lipid lowering drug use on the first Wednesday of October. A patient was defined as incident user if (s)he filled a prescription for lipid lowering medication after a 360 days lipid lowering drug free interval. Both prevalence and incidence estimates were weighted for the sex and age distribution of the general Dutch population.

RESULTS

From 1991 to 1998, the prevalence of lipid lowering drug use increased from 0.5% (95% confidence interval (CI): 0.5, 0.6) to 2.3% (95% CI: 2.2, 2.4) in women and from 0.6% (95% CI: 0.6, 0.6) to 2.9% (95% CI: 2.8, 3.0) in men. Prevalence increased with increasing age and was highest in the age category 60-69 years (in 1998: 9.9% (95% CI: 9.4, 10.4) in women and 11.6% (95% CI: 11.0, 12.1) in men). In 1992, the estimated incidence of lipid lowering drug use was 251(95% CI: 226, 277)/100,000 person years in women and 251(95% CI: 225, 276)/100,000 person years in men. The largest incidence estimates were observed in 1996 (685(95% CI: 644, 726)/100,000 person years in women and 881(95% CI: 834, 928)/100,000 person years in men). After 1996, incidence stabilized in 1997 and decreased in 1998 to 599(561, 637)/100,000 person years in women and 731(688, 773)/100,000 person years in men. Most of the patients (approximately 95%) were treated with one lipid lowering agent. Statins were used by over 90% of patients from 1996 onwards. In 1998, 35% of the patients started with a statin that was not a first choice drug (mainly atorvastatin).

CONCLUSIONS

In the period from 1991-98, prevalence of lipid lowering drug use significantly increased in The Netherlands. However, incidence stabilized and decreased after 1996 which may be explained by the fact that the number of patients eligible for treatment was reached. The question remains whether lipid lowering medication was targeted to the appropriate patients.