Do you know why so many veterans suffer from serious chronic health conditions?

Combat exposure is extremely difficult on the body. Mental trauma aside, service causes serious physical trauma that can lead to chronic conditions years — sometimes decades — later.

These conditions are difficult to diagnose. They’re often difficult to prove. And they can be even more difficult to have covered by VA benefits.

Here’s the problem.

Too many veterans aren’t aware that there’s an established medical connection between their time in combat and the chronic health conditions they suffer from today. Without that link clearly established, a VA benefits claim falls apart.

That’s where Nexus Letters come in.

If you’re a veteran seeking benefits for a chronic condition related to combat exposure, here’s what you need to know:

1. Why Combat Exposure Causes Chronic Conditions Later in Life
2. The Most Common Chronic Conditions Linked to Combat Exposure
3. Why Veterans Often Struggle to Prove Service Connection
4. How to Write a Solid VA Benefits Claim For Your Condition

Why Combat Exposure Causes Chronic Health Conditions

Long story short: the body wasn’t designed to sustain the kind of abuse that combat veterans experience.

Toxic exposures, physical injuries, the stress response… Being in a combat situation damages the body. The scars might not show up immediately, but they do manifest later in the form of chronic conditions.

That’s where Claim Climbers creates evidence-based Nexus Letters built around the medical evidence, working closely with veterans to create personalized letters that clearly establish the connection between their medical condition and their military service.

30% of male veterans aged 25–64 report multiple chronic conditions — compared to only 18% of non-veterans in the same age group.

That’s huge. And it all stems from injuries of war.

Combat exposure causes major changes to nearly every system in the body. Chronic stress causes spikes in cortisol. Burn pits and contaminated water cause lifelong respiratory issues. Physical injuries cause chronic pain conditions that worsen over time.

Put simply: military service causes chronic health issues that don’t show up for years — sometimes decades.

The 7 Most Common Chronic Conditions Linked to Combat Exposure

As you can imagine, combat exposure is linked to just about every chronic condition known to medicine.

The good news is that most have been extensively studied. Many have predictable cause and effect relationships with specific injuries of war.

The most common conditions include:

• Chronic pain
• PTSD & anxiety disorders
• Respiratory conditions (COPD, asthma, etc.)
• Cardiovascular disease
• Sleep disorders
• Arthritis
• Stroke

To make matters worse, studies show that veterans who reported more toxic exposures experienced worsening health over the following decade, long after service had ended. Decades of research confirm that veterans suffer from chronic conditions at significantly higher rates than their non-veteran peers.

Why? Combat exposure.

Why Veterans Have Such a Hard Time Connecting Conditions to Service

Here’s where things get frustrating.

Just because you have a chronic health condition doesn’t automatically mean it’s connected to your military service. When veterans file a VA claim for benefits, they’re on the hook for connecting that condition to service.

Three things must be clearly established:

1. You have a diagnosed medical condition.
2. You were exposed to something or experienced something in service.
3. Your medical condition was directly caused by your service.

That last point is where most veterans struggle. There needs to be some kind of established medical link — also known as a medical nexus.

If you don’t have a medical professional clearly establishing that connection, your claim will be denied.

It’s as simple — and frustrating — as that.

Too many veterans learn about the importance of a nexus letter after their claim has already been denied. By that point, they’re stuck in an appeals process that could take years.

Conditions Veterans Miss MOST When Filing a Claim

Certain medical conditions are more commonly connected to military service than others.

But even though they’re medically linked to veterans, there are still conditions that vets commonly leave off their VA claims because they don’t see the service connection.

Sleep apnea is a great example. Sleep apnea is commonly caused by PTSD, but veterans that suffer from it often go years without being diagnosed — let alone connecting it to their service.

Because of this, sleep apnea is one of the most denied VA claims… as well as one of the most successful appeals.

Here are some other conditions veterans commonly miss:

• Hearing loss / tinnitus (noise exposure)
• Hypertension (combat stress)
• High cholesterol (linked to combat exposure)
• GI conditions (linked to PTSD)

How To Build A VA Benefits Claim For Your Chronic Condition

If you want your VA benefits claim to be successful, you need to be thoughtful about how you file your claim.

Each VA claim for benefits should include:

1. Diagnosis from a medical professional
2. Service records & documentation of exposure/injury
3. Nexus Letter from a doctor connecting your condition to your service
4. Submit your claim with supporting documentation

Step 3 is often skipped. That’s why veterans end up getting denied.

To complete step 3, a Nexus Letter from a doctor is required. This letter should connect your condition to your military service from a medical standpoint.

This doesn’t have to be complicated. Claim Climbers works with veterans to create compelling letters that lay out exactly why your condition should be connected to your service.

Again, don’t leave this step out.

Final Thoughts on How Combat Exposure Causes Chronic Conditions

Combat exposure does a number on the body. Decades of study and research confirm this. The tough part? Knowing how to draw a line from your conditions to your service.

If that line isn’t clearly drawn — and certified by a medical professional — then the VA won’t award any benefits.

To summarize:

1. Combat exposure can lead to chronic health conditions that show up years later
2. Some of the most common chronic conditions include musculoskeletal pain, PTSD, respiratory conditions, and cardiovascular disease
3. In order to qualify for VA benefits, you need to prove that your condition was caused by your service
4. Nexus Letters serve as the foundation of your proof. They clearly outline the connection between your condition and your military service.

Navigating the VA benefits system is complicated. But running into walls because you didn’t know any better isn’t accepting that challenge.

Last modified: March 25, 2026