The relationship between type of drug therapy and blood glucose self-monitoring test strips claimed by beneficiaries of the Seniors' Pharmacare Program in Nova Scotia, Canada

BACKGROUND

The healthcare expenditure on self-monitoring of blood glucose (SMBG) test strips under the Nova Scotia Seniors' Pharmacare Program (NSSPP) has increased significantly in recent years. The objective of this study was to identify the frequency and cost of claims for blood glucose monitoring test strips by NSSPP beneficiaries in the fiscal year 2005/06 and to explore the variation in the use of test strips by type of treatment, age and sex.

METHODS

Retrospective analysis was conducted using pharmacy administrative claims data for NSSPP beneficiaries. Study subjects were aged > or = 65 years on October 1, 2004, received SMBG test strips in the 110 days prior to April 1, 2005, and were alive throughout the twelve month study period. Subjects were categorized into four groups: insulin only, oral antihyperglycemic agents (OAA) only, both OAA and insulin; and no reimbursed diabetes medications. Statistical analysis was performed to identify differences in expenditure by medication group and in frequency of SMBG test strips claimed by medication group, age, and sex.

RESULTS

Of 13,564 included beneficiaries, 13.2% were categorized as insulin only, 53.5% OAA only, 7.2% both OAA and insulin, and 26.0% no reimbursed diabetes medications. Over half (58.7%) were femle. The insulin only category had the highest mean (+/- SD) number of SMBG test strips claimed per day (2.0 +/- 1.5) with a mean annual total cost of $615 +/- $441/beneficiary. Beneficiaries aged 80 years and above claimed fewer test strips than beneficiaries below 80 years.

CONCLUSION

This population based study shows that in Nova Scotia the SMBG test strips claimed by the majority of seniors were within Canadian guidelines. However, a small proportion of beneficiaries claimed for SMBG test strips infrequently or too frequently, which suggests areas for improvement. The provincial drug plan covers the majority of the costs of test strip utilization, suggesting that the majority of test strips claimed did not exceed the maximum allowable cost (MAC) established in the program's MAC policy. Drug insurance programs need to work with healthcare providers to determine if patients are using test strips optimally; and to determine their impact on patient outcomes. In addition, they need to determine the cost-effectiveness of their SMBG test strip reimbursement policies.

The Effect of Deinsuring Chlorpropamide on the Prescribing of Oral Antihyperglycemics for Nova Scotia Seniors’ Pharmacare Beneficiaries

On behalf of the Nova Scotia Seniors' Pharmacare Program, the Drug Evaluation Alliance of Nova Scotia developed a multicomponent intervention plan to facilitate the removal of chlorpropamide as an insured benefit. Chlorpropamide has caused serious hypoglycemia in seniors to a greater extent than some other agents. Pharmacy administrative claims were used to compute monthly use rates for insulin and each oral antihyperglycemic drug from January 1, 2000-December 30, 2002, in an intervention cohort (patients receiving chlorpropamide) and a control cohort (patients receiving an antihyperglycemic agent other than chlorpropamide). Initially, 630 patients were receiving chlorpropamide therapy. By the time chlorpropamide was deinsured, only 10% of the treatment cohort continued receiving chlorpropamide; shortly after deinsurance, no beneficiaries continued receiving the drug. The antihyperglycemics with the greatest increase in prescription were glyburide and gliclazide. The deinsuring of chlorpropamide and the educational strategies that accompanied it resulted in the selection of more appropriate antihyperglycemics for Nova Scotia seniors.