Secure messaging represents an emerging avenue by which veterans and other patients can asynchronously access primary care services. To our knowledge, this study is the first to identify and characterize secure messaging high users in primary care using a national sample in an integrated health system after the onset of the COVID-19 pandemic.26

Collectively, this study’s findings have several implications relevant to understanding access to and use of asynchronous primary care. First, patient characteristics including being older and more frail and having a higher degree of physical comorbidity were associated with higher adjusted odds of being a secure messaging high user. Secure messaging may therefore be an important primary care access point for higher-need populations. These exchanges might reduce the barrier for between-visit communication, obviate the need for some synchronous primary care by completely addressing certain medical concerns (eg, medication refills), and provide a workaround to mobility challenges related to getting to in-person appointments or other challenges (eg, difficulty hearing) related to telephone or video visits. Additionally, for rural residents, secure messaging may serve as an avenue to circumvent geographic barriers to accessing primary care.27 We found, however, that rural veterans were less likely to be high users. Although secure messaging can overcome poor access due to geography, rural patients may just use less care altogether.7,28,29 More work is needed to understand use of this form of communication among rural populations.

For patients with mental health conditions, secure messaging may be a more approachable primary care access option that alleviates the stigma preventing access to primary medical or mental health care.30-32 Particularly as most secure messaging high users did not also use other types of primary or emergency care at high rates, attention should be paid to maintaining care continuity via secure messaging access for these populations.

Second, this study’s findings that veterans who identify as members of a racial minority group have lower adjusted odds of being high users have important equity implications. Patients from historically marginalized racial groups experience inequities related to health care use, access, and outcomes, including in primary care.33-35 Our study suggests that historic disparities in use of other care services also extend to primary care secure messaging. It is conceivable that racial disparities in primary secure messaging use are related to technology-specific disparities such as differences in digital literacy,36 a new illustration of racial differences in earned mistrust of health care institutions,37 or a combination of multiple factors.

Given that secure messaging is assuming a growing role in primary care, future research can focus on specific barriers faced by these populations so that this form of communication can become more equitably used. Additionally, our study’s finding that veterans who lived in neighborhoods having higher socioeconomic status were more likely to be high users also has equity implications. This situation creates an additional pathway to widen inequities in access to primary care services. This finding may be in part explained by known socioeconomic disparities in digital literacy.38

Third, our study’s finding that most secure messaging high users do not use other primary care services or the emergency department at the same high frequency as secure messaging has implications for care delivery. For example, family medicine clinicians may use targeted approaches for chronic disease management (eg, diabetes management) or preventive care (eg, conversations about screenings) in a way that leverages secure messaging.8,39-41

Fourth, this study’s findings that a substantial percentage of total primary care secure messages are exchanged with high users, and that veteran-generated messages make up a high proportion of the messages in these exchanges help shed light on family medicine clinician workload and burnout.10 This is particularly important to understand in the context of increasing electronic health record workload and associated burnout, and workforce supply challenges in primary care.42,43 Secure messaging is a major component of the electronic health record–related workload, and characterizing the nature of that workload to identify opportunities to safely reduce it is worthwhile. Some research has characterized the content of primary care secure messaging among all users in the VHA, showing that 90.4% of threads are initiated by patients, less than 1% of messages are clinically urgent, and the most common reasons for secure messages are medication renewals and refills (47.2% of messages), scheduling requests (17.6%), medication issues (12.9%), and health issues (12.7%).44 There is an evidence gap, however, related to differences in the content of primary care secure messages sent by high users vs non–high users. Future research can identify common categories of messages sent by high users that might be addressed by a nonphysician member of the team or by a different care setting. Subsequently, family physicians and health systems can develop standardized workflows tailored to individual patient needs (eg, routing routine refill requests to clinical pharmacists, routing urgent messages to an emergency triage line) in a way that maintains access to primary care for high users while also reducing burden on individual clinicians. Additionally, the high volume of secure messages exchanged between high users and primary care teams illustrates the considerable work primary care dedicates to secure messaging. This study therefore adds insight in support of insurance reimbursing primary care teams for addressing patient-initiated secure messages as a covered service. Particularly as individuals who are frail or have physical comorbidity are more likely to be high users, however, secure messaging reimbursement policies should be mindful of any patient cost sharing that is too prohibitive of using this essential primary care access point.45

This study has limitations. First, whether a veteran is a high user or not, and use in general, does not completely measure access to secure messaging or to primary care generally. Access is a complex concept that includes actual use, experienced and perceived barriers to care, and perceived need for care.46

Second, our cohort included only veterans who used secure messaging at least once. We wanted to ensure that our population represented individuals who had at least tried engaging with the technology and that the 95th percentile or higher threshold represented patients who actually used secure messaging at especially high rates. We also chose this cohort design because barriers to initially join secure messaging platforms may differ from barriers to use among those who use secure messaging. It is conceivable, however, that the racial and socioeconomic disparities in use that we observed would be more pronounced or better appreciated in a cohort that included secure messaging nonusers.

Third, this study does not provide insight into the time and cognitive resources required of primary care clinicians to respond to messages, which can be an area of future study. Fourth, although this study focuses on individual-level secure messaging use, it does not describe ways in which possible VHA facility-level variation in secure messaging may influence patients’ use of secure messaging, which is likewise an area of future research.

Fifth, our analysis does not identify whether messages were sent by caregivers or family members on behalf of patients, or by the patients themselves. Last, this study focused on the use of primary care secure messaging in the VHA, rather than in a non-VHA setting, which may limit generalizability.

Despite these limitations, this study represents the most up-to-date analysis available of patient use patterns of secure messaging in primary care. Our findings can help inform family physicians and policy makers on which patient subgroups are most prone to use secure messaging at high rates for receipt of primary care services, which can direct clinical care and population health initiatives. They can also help practice leaders identify patient populations whose primary care secure messaging access might be most affected by policy changes.

This study showed that secure messaging high users are older, have relatively higher degrees of complexity and frailty, and are more likely to have mental health conditions, and also are more likely to be White and live in neighborhoods with higher socioeconomic status. Additionally, we found that a small percentage of patients account for a disproportionate share of total primary care secure messages, and that high user exchanges feature a greater percentage of patient-generated messages. Most secure messaging high users in our cohort did not use other primary and emergency care services at the same high frequency as secure messages. The content of secure messages from high users is still unknown and remains an area of future research. On the basis of these collective findings, family medicine clinicians and health systems should safeguard primary care secure messaging access for more clinically complex patients, address barriers contributing to disparities in use, and identify opportunities to safely reduce the primary care secure messaging workload.