Cataract Secondary to Type 2 Diabetes Claim Guide

We analyzed the Board's published decisions and found cataract (DC 6027) claimed as secondary to type 2 diabetes (DC 7913) is a real, mid-sized claim pool that loses more often than it wins once it reaches a merits decision.

How those 680 issues came out

The ICD-10 diagnosis codes most commonly used for DC 6027, Cataract (the kind on your medical records, decision letter, or C&P exam report). VA rates the disability and its residuals, not the diagnosis itself, so coding can vary.

See the full diagnostic-code page →

Under 38 CFR 3.310 a secondary claim turns on three elements:

• A current diagnosis: a medical diagnosis of cataract (the secondary).
• A service-connected primary: Type 2 Diabetes, already service-connected (the primary). A 0% primary still counts.
• A medical nexus: a medical opinion linking the cataract to the type 2 diabetes, showing the primary caused or aggravated it.

See the Secondary Claim guide for the caused-versus-aggravated split, and the Nexus Letter guide for what makes the medical opinion strong.

Whether that medical link exists in any one case is a medical question decided on that case's own evidence (the nexus).

The outcome split above counts whole issues. This section goes one layer deeper. Under 38 CFR § 3.310 a secondary claim can be won two ways: the type 2 diabetes caused the cataract (§ 3.310(a)), or it aggravated an existing cataract (§ 3.310(b)). Every grant rests on one or the other, so the numbers below divide up the granted claims only.

Direct causation is the route that carries most grants here: 87% of them found the type 2 diabetes caused the cataract, the rest found aggravation. A practical consequence for the nexus opinion: it should address both routes, because a medical opinion that only argues causation leaves the aggravation theory, a separate legal basis, on the table. See the caused-vs-aggravated guide for how the two theories differ.

On the other side: in 99 denied claims the Board looked at this pairing and found no link, meaning it decided the type 2 diabetes neither caused nor worsened the cataract. That is a separate group from the grants above, counted here so the picture is not one-sided.

We analyzed published Board decisions on this pairing to build this split. The grant split covers granted claims only; denied, remanded, and dismissed claims are not in it. Descriptive of the published record, not a prediction.

What veterans who win this pairing actually put in the file, and why each piece moves the claim.

• Diabetes control records: Pull your HbA1c results and glucose logs covering the years before your cataract showed up. VA wants to see your blood sugar was running high during that window, since poorly controlled diabetes is what speeds cataracts along.
• Current eye exam with diagnosis and type: Get a recent ophthalmology or optometry report (within the last 12 months) that names the cataract and its type (nuclear, subcapsular, or cortical). An old exam from years back will not carry your claim, VA needs proof of what your eye looks like now.
• Corrected vision testing, not just "I can't see": VA rates cataracts on your BEST corrected vision (with glasses or contacts), not how you see without them. Get a Snellen or LogMAR test and, if possible, visual field testing (Humphrey perimetry). If your corrected vision is 20/40 or better in both eyes, this can hurt your rating even with a valid diagnosis, so know that number going in.
• Imaging that shows the lens over time: Slit-lamp photos or OCT scans document where the clouding sits in the lens and let you show it progressing alongside your diabetes. This backs up the timeline your nexus letter will lean on.
• A clear timeline: Line up when your diabetes was diagnosed with when the cataract first showed up in your records. VA is looking for the cataract to follow the diabetes, not come first or show up completely disconnected from it.
• A strong nexus letter that names the mechanism: The letter should say "at least as likely as not," not "possibly" or "may be." It should also explain HOW diabetes causes the damage, immune cells traveling into the lens and disrupting its cells, plus the swelling and pressure changes from blood sugar swings, not just "diabetes causes cataracts." A letter that skips the mechanism reads as a guess, and VA denies guesses.
• State causation or aggravation, and rule out other causes: The letter needs to pick a lane, either diabetes caused the cataract outright, or it made an existing one worse, and say which. It should also address (and rule out) other common causes like age, past eye injury, or steroid use, since VA denies claims where an examiner can point to another likely cause you never addressed.
• Proof the provider reviewed your actual records: The nexus letter should state plainly that the provider read your service records and medical history, with dates. A letter that never mentions reviewing your file reads as speculation, and that is one of the most common reasons these claims get denied.

The Board has granted service connection for cataracts as secondary to diabetes mellitus in several published decisions. These cases are not binding on future claims, and each one turned on its own medical evidence. Still, they show a pattern worth understanding if you are pursuing a similar claim.

The VA assigns one of these percentages based on what your medical record documents. Plain-language summary of the rating criteria at 38 CFR; the controlling text is the regulation itself.

Every item below comes from a pattern in the decisions on this pairing, not from general claim advice.

For the mechanics of filing itself, see the Standard Claim Guide and the Fully Developed Claim Guide.

A secondary claim moves through the same pipeline as any other. Understanding who does what helps you know who to contact and what to expect.

1. You file the claim, naming Type 2 Diabetes as the service-connected primary and cataract as secondary. Directly with VA, through VA.gov, or with an accredited representative's help.
2. VA assigns a Veteran Service Representative (VSR) to develop the claim: gather your service treatment records, VA and private medical records, and order a C&P exam if needed.
3. The C&P exam is conducted, usually with the examiner asked to address the specific secondary theory (causation and aggravation both).
4. The file goes to a Rating Veteran Service Representative (RVSR), the "rater," who weighs the medical evidence and decides service connection and, if granted, the rating percentage.
5. VA issues the decision letter stating the outcome and the reasoning.
6. If denied or under-rated, you choose an appeal lane, Supplemental Claim, Higher-Level Review, or a Board appeal, covered below.

Who's who: VSO vs. VSR vs. Rater vs. C&P Examiner

For the full walkthrough, see Inside Your Claim and Claim Stages.

A Disability Benefits Questionnaire (DBQ) is the standardized form the examiner completes for your condition. See the DBQ Guide for how these forms work and whether a private DBQ from your own doctor can be submitted instead of relying solely on a VA exam. For what to expect and how to prepare, see the C&P Exam Prep Guide, and be specific about how your cataract symptoms relate to your type 2 diabetes timeline, treatment, and any aggravation, that is the detail a nexus opinion relies on.

Your decision letter has a narrative "reasons and bases" section and a codesheet with the rating and effective date. See the Reading Your Decision Letter Guide or use the Letter Interpreter tool to decode your own letter. If denied, you have three main lanes:

• Supplemental Claim: refile with new and relevant evidence, such as a nexus opinion that addresses the mechanism and the specific VA rationale you're rebutting. See Supplemental Claim Guide.
• Higher-Level Review (HLR): a senior reviewer looks at the same evidence again, useful if the denial rested on a legal error. See HLR Guide.
• Board Appeal: your case goes to a Veterans Law Judge, with a direct review, evidence, or hearing docket. See Board Appeal Guide.

Not sure which lane fits? See the Appeals decision guide for a side-by-side comparison.

Keep documentation of ongoing treatment, follow-up evaluations, and any updated diagnostic testing for your cataract on file, this protects you if VA schedules a future reexamination. See Protect Your Rating for when a rating becomes protected and Future Reexaminations for what triggers one. If your cataract worsens, see the Rating Increase Guide.