Sleep Apnea Secondary to PTSD: VA Claims Guide & Nexus Letter Tips

Sleep apnea is one of the most commonly claimed secondary conditions among veterans with PTSD—and for good reason. Medical research increasingly supports the link between PTSD and obstructive sleep apnea (OSA), and a successful secondary claim can significantly increase your combined disability rating and monthly compensation. This guide walks you through everything you need to file a strong claim for sleep apnea secondary to PTSD.

What Is Secondary Service Connection?

Secondary service connection means a condition was caused or aggravated by an already service-connected disability. You don't need to prove the secondary condition happened during service—only that your service-connected condition led to it.

For sleep apnea secondary to PTSD, you need to establish:

1. A current diagnosis of sleep apnea (confirmed by a sleep study)
2. An existing service-connected PTSD rating
3. A medical nexus linking your PTSD to your sleep apnea

This is different from a direct service connection claim, where you'd need to prove sleep apnea began during or was directly caused by military service.

Why Secondary Claims Are Powerful

Many veterans don't realize that secondary conditions are one of the most effective ways to increase a combined rating. You already have one piece of the puzzle—service connection for PTSD. Adding secondary conditions builds on that foundation without having to prove new in-service events.

The Medical Link Between PTSD and Sleep Apnea

The connection between PTSD and sleep apnea is supported by a growing body of medical research. Here are the primary mechanisms:

Hyperarousal and Sleep Fragmentation

PTSD causes a state of chronic hyperarousal—the nervous system stays in "fight or flight" mode even during sleep. This leads to fragmented sleep patterns that weaken upper airway muscle tone, contributing to airway collapse during sleep (the hallmark of obstructive sleep apnea).

Weight Gain from PTSD Medications

Many PTSD medications—including SSRIs like sertraline (Zoloft) and paroxetine (Paxil), as well as atypical antipsychotics like quetiapine (Seroquel)—are associated with significant weight gain. Increased body weight, particularly around the neck and throat, is a primary risk factor for obstructive sleep apnea.

Autonomic Nervous System Dysfunction

PTSD disrupts the autonomic nervous system, which controls involuntary functions including breathing during sleep. Research published in the Journal of Clinical Sleep Medicine has shown that veterans with PTSD have significantly higher rates of sleep-disordered breathing compared to those without PTSD.

Key Research Studies

• Colvonen et al. (2018) – Found that PTSD is an independent risk factor for OSA, even after controlling for BMI and other variables
• Zhang et al. (2017) – Meta-analysis showing veterans with PTSD had a significantly elevated risk of obstructive sleep apnea
• Lettieri et al. (2009) – Demonstrated that combat veterans with PTSD had higher rates of sleep apnea than non-PTSD veterans

Evidence You Need for a Successful Claim

Building a strong secondary claim requires layering multiple types of evidence:

1. Sleep Study (Polysomnography)

A formal sleep study is essential. The VA requires a diagnosis of sleep apnea confirmed by polysomnography showing a specific number of apnea-hypopnea events per hour (AHI). Home sleep tests may be accepted, but in-lab polysomnography is the gold standard.

2. Current PTSD Service Connection

Your PTSD must already be rated and service-connected. If you haven't yet filed for PTSD, you'll need to establish that connection first before filing sleep apnea as secondary.

3. Nexus Letter

A nexus letter from a qualified medical professional is often the single most important piece of evidence. The letter must:

• Be written by an MD, DO, or qualified sleep specialist
• Review your complete medical records (PTSD treatment, medications, sleep study results)
• Explain the medical mechanism linking PTSD to sleep apnea
• Use the magic words: "at least as likely as not" (≥ 50% probability)
• Cite relevant medical literature

Sample Nexus Statement for Sleep Apnea Secondary to PTSD

"It is at least as likely as not (≥ 50% probability) that the veteran's obstructive sleep apnea is secondary to his service-connected PTSD. The veteran's chronic hyperarousal state, documented PTSD medication regimen (sertraline, prazosin), and associated weight gain of 45 lbs since PTSD onset are all established contributing factors to the development of obstructive sleep apnea per current medical literature (Colvonen et al., 2018; Zhang et al., 2017)."

4. Supporting Documentation

• Buddy statements from your spouse or partner describing your snoring, breathing pauses, and daytime fatigue
• Medical records showing the timeline of PTSD treatment and sleep apnea onset
• Medication records documenting weight gain or sleep disturbance side effects
• VA treatment notes referencing sleep complaints

Sleep Apnea Rating Levels

The VA rates sleep apnea under Diagnostic Code 6847 (Sleep Apnea Syndromes). Here's how ratings break down:

The 50% Rating Is Most Common

The majority of veterans with sleep apnea receive a 50% rating because they use a CPAP machine. If you've been prescribed a CPAP, make sure your medical records clearly document:

• The CPAP prescription and compliance data
• That the CPAP is medically necessary (not optional)
• Your ongoing use and any adjustments

How Sleep Apnea Affects Your Combined Rating

Adding sleep apnea to an existing PTSD rating has a significant impact. Here are common scenarios using VA math:

Even if your PTSD is rated at 50%, adding a 50% sleep apnea secondary rating jumps your combined to 70%—crossing a major benefits threshold.

Common Mistakes That Get Claims Denied

1. No Formal Sleep Study

Self-reporting symptoms isn't enough. You must have a polysomnography or approved home sleep test confirming the diagnosis.

2. Weak or Missing Nexus Letter

Without a medical opinion connecting PTSD to sleep apnea, the VA will likely deny the secondary connection. A C&P examiner may not draw the connection for you.

3. Filing Before PTSD Is Rated

Your PTSD must be service-connected before you can claim sleep apnea as secondary. File them in the correct order, or file simultaneously with a clear explanation.

4. Not Addressing BMI

The VA may argue that obesity—not PTSD—caused your sleep apnea. A strong nexus letter should explain how PTSD (through medication side effects and lifestyle changes) contributed to weight gain, and how hyperarousal independently contributes to OSA regardless of weight.

Filing Your Secondary Claim: Step by Step

1. Get a sleep study – Obtain a formal diagnosis of obstructive sleep apnea
2. Gather medical records – Compile PTSD treatment records, medication history, and sleep study results
3. Obtain a nexus letter – Get a medical opinion linking PTSD to sleep apnea
4. File VA Form 21-526EZ – Select "secondary" as the claim type and identify PTSD as the primary condition
5. Attend the C&P exam – Bring copies of your nexus letter and supporting evidence
6. Follow up – Monitor your claim status on VA.gov

Discover Additional Benefits at Your New Rating

A higher combined rating doesn't just mean more monthly compensation—it unlocks a cascade of additional federal and state benefits that many veterans miss entirely.

The Veterans Benefits Finder analyzes your complete profile—rating, location, dependents, and service history—to show you every benefit available. Veterans who increase their rating through secondary conditions like sleep apnea often discover they now qualify for property tax exemptions, education benefits for dependents, and state-specific programs worth thousands annually.