Data Brief: Insulin and Metformin Geographic Access and Mail‑Order Use
In 2022, insured Californians traveled an average distance of 8.2 miles to obtain insulin in person, and obtained 20.5% of insulin prescriptions through mail order, while metformin has an average distance traveled of 6.1 miles, with 24.9% of prescriptions coming via mail order.
Introduction
This data brief presents four maps to examine the average distance traveled and percentage of mail order prescriptions for insulin and oral medication metformin in California by county in 2022. For this data brief, mail order pharmacies are defined as pharmacies with the mail order indicator in the Healthcare Payments Data (HPD) Program. Insulin and Metformin are used to manage diabetes and may be prescribed concurrently. Insulin is a hormone that is directly injected into the patient’s body to regulate glucose levels while metformin is an oral medication that improves insulin sensitivity to help regulate blood glucose levels. Insulin must be kept in the refrigerator prior to use and must be delivered using cold chain to maintain the appropriate storage temperatures. Any barrier to easily obtaining insulin or metformin is likely to negatively impact people who rely on a consistent supply of these drug products for disease management, such as individuals living with diabetes and other chronic conditions. Higher average distance traveled to obtain a prescription may serve as an indicator of limited pharmacy access, which can create barriers to timely and consistent medication.
Another indication of potential limited pharmacy access is reliance on mail order prescription services to receive medications. Community pharmacies are important providers of health care resources such as over the counter medications, emergency preparedness support, and durable medical equipment. Although mail order prescriptions can offer cost savings and convenience1,2 when reliance of these services is driven by a lack of local pharmacy infrastructure, individuals in affected communities may experience reduced access to essential in-person health care services.
It is important to note that access to mail order prescriptions is influenced by health plan policies. Some health plans incentivize pharmaceutical mail order services through reduced or waived copayments while other plans have limited options for such services and others do not offer mail order services for insulin and metformin at all. Mail order distribution channels may limit patient access to more affordable drug options such as generic variants of brand name insulin products.3,4,5 Areas with both increased mail order service utilization and higher average travel distance may be areas that state policymakers target with interventions to create more equitable access to affordable medications.
The analyses for this report were conducted using data from California’s Healthcare Payments Data (HPD) Program. HPD is California’s All Payer Claims Database or APCD; it is a research database comprised of healthcare administrative data: claims and encounters generated by transactions among payers and providers on behalf of insured individuals. For additional information about the HPD Program, including details on data sources, populations included, and data elements available, see HPD Public Reporting FAQ, HPD Resources and the HPD Snapshot (and its Technical Note).
The following visualizations present data from retail pharmaceutical claims paid for by Medicare or commercial plans. At this time, Medi-Cal does not report the pharmacy mail order indicator to HCAI as part of its HPD data submission.
Key Findings
- Some counties in the far north of California show increased average distances traveled, but do not show increases in mail order percentages. The largest discrepancies, for both insulin and metformin, are found in Inyo County (in the eastern part of the state), which has one of the largest average distances traveled but one of the smallest mail order percentages. This may indicate that insulin and metformin can only be obtained in these areas through lengthy travel.
- Conversely, there are counties in the Bay Area and Central Valley which show the opposite relationship: reduced distance traveled and increased mail order percentages. As noted above, this may indicate that mail order provides some access in the absence of brick-and-mortar pharmacies but is also a possible indicator of limited access to certain types of healthcare resources.
Visualization
Notes:
- Only 0.1 percent of prescriptions included both insulin and metformin at the same time.
- Mail‑order prescriptions were excluded from distance‑traveled calculations.
How HCAI Created This Product
- This report follows the California Health and Human Services Agency’s Data De-Identification Guidelines. Data from any group with less than 30 individuals is removed from the analyses and suppressed in the visualizations.
- This product uses a different suppression method than the Healthcare Payments Data (HPD): Fee-For-Service Drug Costs in California report. The Fee-For-Service Drug Costs in California report excluded drug products (based on National Drug Code or NDC) that were prescribed to fewer than 100 individuals in a year, while this report excludes drug names that were prescribed to fewer than 30 individuals in a year. These differences in suppression methods will cause the overall numbers to differ between the two products.
- For more information about the standard exclusion criteria that were applied, please see the Technical Note for the Fee-For-Service Drug Costs in California report.
Additional Information
Topic: Cost Transparency / Healthcare Quality
Source Link: Cost Transparency – Healthcare Payments Database
Citation: HCAI – Healthcare Payments Database – Insulin and Metformin Geographic Access and Mail‑Order Use
Temporal Coverage: 2022
Spatial/Geographic Coverage: Statewide, County
Frequency: Annually