Trends in Mail-Order Prescription Use among U.S. Adults from 1996 to 2018: A Nationally Representative Repeated Cross-Sectional Study

Abstract Background Mail-order prescriptions are popular in the U.S., but the recent mail delays due to operational changes at the United States Postal Services (USPS) may postpone the delivery of vital medications. Despite growing recognition of the health and economic effects of a postal crisis on mail-order pharmacy consumers, little is known about the extent of mail-order prescription use, and – most importantly – the population groups and types of medications that will likely be most affected by these postal delays. Methods The prevalence of mail-order prescription use was assessed using a nationally representative repeated cross-sectional survey (the Medical Expenditure Panel Survey) carried out among adults aged 18 and older in each year from 1996 to 2018. We stratified use of mail-order prescription by socio-demographic and health characteristics. Additionally, we calculated which prescription medications were most prevalent among all mailed medications, and for which medications users were most likely to opt for mail-order prescription. Findings 500,217 adults participated in the survey. Between 1996 and 2018, the prevalence of using at least one mail-order prescription in a year among U.S. adults was 9·8% (95% CI, 9·5%-10·0%). Each user purchased a mean of 19.4 (95% CI, 19·0-19·8) mail-order prescriptions annually. The prevalence of use increased from 6·9% (95% CI, 6·4%-7·5%) in 1996 to 10·3% (95% CI, 9·7%-10·9%) in 2018, and the mean annual number of mail-order prescriptions per user increased from 10·7 (95% CI, 9·8-11·7) to 20·5 (95% CI, 19·3-21·7) over the same period. Use of mail-order prescription in 2018 was common among adults aged 65 and older (23·9% [95% CI, 22·3%-25·4%]), non-Hispanic whites (13·6% [95% CI, 12·8%-14·5%]), married adults (12·7% [95% CI, 11·8%-13·6%]), college graduates (12·2% [95% CI, 11·3%-13·1%]), high-income adults (12·6%, [95% CI, 11·6%-13·6%]), disabled adults (19·3% [95% CI, 17·9%-20·7%]), adults with poor health status (15·6% [95% CI, 11·6%-19·6%]), adults with three or more chronic conditions (24·2% [95% CI, 22·2%-26·2%]), Medicare beneficiaries (22·8% [95% CI, 21·4%-24·3%]), and military-insured adults (13·9% [95% CI, 10·8%-17·1%]). Mail-order prescriptions were commonly filled for analgesics, levothyroxine, cardiovascular agents, antibiotics, and diabetes medications. Interpretation The use of mail-order prescription, including for critical medications such as insulin, is increasingly common among U.S. adults and displays substantial variation between population groups. A national slowdown of mail delivery could have important health consequences for a considerable proportion of the U.S. population, particularly during the current Coronavirus disease 2019 epidemic. Research in context Evidence before this study In July 2020, major cost-cutting actions at the United States Postal Service (USPS) caused a sudden slowdown in mail delivery on a national scale. In addition to jeopardizing mail-in ballots for the upcoming November’s general election, such a remarkable postal delay may also deteriorate the health of many individuals who rely on the postal service to deliver their essential medications. The current SARS-CoV-2 epidemic may further amplify the postal crisis given anecdotal evidence that many patients have switched to mail-order prescriptions to avoid potential exposures to the virus at drugstores. Efforts aimed at addressing the health and economic effects of delayed medication delivery require an understanding of the national prevalence of mail-order prescription and the population groups who will likely be most affected by these postal delays. We searched PubMed for articles published on or before September 14, 2020 that described patterns of mail-order medication use using variations of the search terms “mail-order,” “medication,” and “United States.” We found no empirical evidence on trends in the use of mail-order medications at the national level or how such use varied by population subgroups. Added value of this study To our knowledge, this study is the first to document time trends in the use of mail-order medications using data from a nationally representative cross-sectional sample of U.S. adults for each year from 1996 to 2018. Given the lack of evidence on the use of mail-order medications, the three key contributions of this study are to (i) demonstrate a relative increase of more than 50% in the prevalence of using mail-order prescription from 1996 to 2018, (ii) highlight population groups heavily relying on mail-order prescriptions and who are, thus, most likely to be affected by a decline in the availability or reliability of mail-order prescriptions from cost-cutting measures at the USPS, and (iii) document medications most commonly delivered by mail so that policy makers and clinicians can design effective interventions to alleviate the consequences of delayed or absent mail-order prescriptions. Implications of all the available evidence We show that the use of mail-order medications has become more prevalent among U.S. adults over the past two decades, with an increase from 13.5 million adults in 1996 to 25.9 million adults in 2018. Given that USPS delivers 55% of all mail-order medications, a considerable proportion of mail-order pharmacy consumers could experience a delay or non-delivery of their medications. The use of mail-order medications is most common among older adults, disabled and chronically ill persons, and military-insured beneficiaries, who may have limited access to a local drugstore due to their morbidities or disability. In addition, we document a variety of medications frequently delivered by mail – ranging from those for which missing several doses does not result in immediate adverse health consequences (e.g. statins), to those for which missing a dose could be detrimental to the patient’s health (e.g. insulin). Our findings highlight that any disruption in the postal service could lead to important medical complications among a considerable proportion of the vulnerable U.S. population. The potential health consequences of a widespread national slowdown in mail delivery should be considered when weighing options to reverse recent changes at the USPS.