When is a subject line PHI?

Email subject lines are highly visible; they appear in inbox previews, thread views, server logs, and often in unencrypted routing metadata. Unlike the main body of an email, which can be shielded through encryption technologies, the subject line frequently lacks these protections, making any protected health information (PHI) included in it vulnerable to unauthorized exposure. Therefore, including specifics like patient names, medical record identifiers, or details about diagnoses or treatments in subject lines can result in inadvertent privacy breaches. 

A Journal of the American Medical Informatics Association study on electronic health records (EHRs) shows, “metadata…can be recorded unobtrusively and capture [use] at a scale unattainable through direct observation or self-reports,” meaning that even seemingly small data points like subject lines can leave behind a trail of sensitive information that can be aggregated, analyzed, and potentially misused.

Yet, this does not mean healthcare organizations are entirely barred from personalization or specificity in subject lines. When using HIPAA compliant email solutions, like platforms that provide encryption covering both email body and subject line, there is a safer environment for incorporating limited patient-specific information. This technology protects PHI even in the metadata, allowing healthcare providers to send appointment reminders or health alerts with some degree of personalization. 

The personability of putting PHI in email subject lines 

Humans naturally prioritize information that feels directly addressed to them, a concept known in psychological science as the self-reference effect. When a subject line includes personal information, the recipient's brain is effectively cued that this communication is important, increasing the likelihood that it will be read rather than ignored or deleted.

A 2023 Marketing Letters article investigating the framing of email subject lines notes “simply adding the name of the recipient to the subject line of an email significantly increases the performance of email campaigns. In the last years, this “trick” has become a common practice from marketers to catch the attention of their audience, hoping to increase the opening rates and click-through rates of their email campaigns.”

However, personalization is not just about inserting a name. True engagement arises when personalization is purposeful and contextual. Strategic personalization respects the patient’s time and intelligence, making every email a valued interaction rather than an intrusion.

See also: Can you personalize a healthcare email?

Can PHI be included in an email subject line?

A paper from the American Health Lawyers Association notes healthcare organizations should, “Avoid disclosing an individual’s PHI in the subject line of an email; encryption methods might not encrypt the subject line.”

Sharing PHI in a subject line can only be done when HIPAA compliant email software like Paubox is used. Without these technical safeguards, including PHI in subject lines is a risky practice that opens the door to potential privacy violations. 

The definition of PHI extends to every part of electronic communications, including elements like email subject lines. With subject lines frequently exposed in inbox previews, server logs, and intermediate transmission points, creating a vulnerable window where sensitive health information might be seen by unintended viewers. This exposure is why healthcare providers are urged to approach PHI in subject lines with great caution. HIPAA compliance does not necessarily equate to an outright ban on PHI in subject lines. 

The risk of putting PHI in email subject lines 

Inadvertent misaddressing or auto-fill errors are common in busy healthcare settings. An email with PHI in the subject line sent to the wrong recipient instantly becomes a breach, exposing private health information in a way that can harm patients and damage institutional reputations. 

Even beyond delivery mistakes, the journey of an email across multiple servers is riddled with security pitfalls. An Open Medicine study notes, “email is not sent; it is copied,” which means that “copies of email are generated on multiple computers” along the way. Each copy becomes a potential weak point where unauthorized access is possible.

The College of Physicians and Surgeons of Ontario warns that “e-mailing or faxing unencrypted patient health information is really no more secure than sending that information on a postcard.”

Many email providers and systems do not enforce strict encryption. At any point along the digital pathway, if encryption fails or is absent, PHI in subject lines can be intercepted by malicious actors or exposed in less secure backup systems. This creates a glaring vulnerability. 

How to avoid putting PHI in an email subject line

Audience segmentation is achieved by grouping patients based on shared characteristics like demographics, clinical conditions, or treatment phases. The technique lets healthcare providers tailor content that feels specific and valuable to each segment. 

A group managing hypertension might receive different educational content than patients undergoing post-operative rehabilitation. This targeted alignment makes patients feel understood and more inclined to engage. A Journal of Medical Internet Research study explains, personalization in digital technologies is “a process that changes the functionality, interface, information access and content, or distinctiveness of a system to increase its personal relevance to an individual or a category of individuals.”

Personalization can also be explicit, where “information needed for user models requires users’ active participation,” or implicit, where it is “obtained automatically through the analysis of observed user activities and interactions with the system.”

Personalization can take form in the email body through dynamic content, pieces of text or offers that change depending on the recipient’s profile. Instead of revealing personal details prematurely in the subject line, dynamic sections inside the email can display tailored health tips, appointment reminders, or medication adherence prompts based on securely stored patient data. It delivers an experience that feels genuinely individualized.

FAQs

Can providers use PHI to personalize communications without patient authorization?

Yes, in many cases. HIPAA allows providers to use PHI for treatment, payment, and health care operations without specific patient authorization. For example, sending a medication reminder or care plan update to a patient is usually permitted because it supports treatment.

What personalization practices may violate HIPAA?

Including sensitive health details in an unsecured email subject line, sharing PHI with third parties without proper safeguards, or using PHI for advertising without patient consent could all violate HIPAA. Even well-intentioned personalization can create risks if data is not encrypted or shared beyond the minimum necessary.

Can patients opt out of personalized communication?

Yes. Patients generally have the right to request restrictions on how their PHI is used or disclosed.