Diabetic retinopathy (DR) is a common vision complication of diabetes. Health experts refer to the early stages of the condition as nonproliferative diabetic retinopathy (NPDR). The term proliferative diabetic retinopathy (PDR) describes the most severe stage of this eye problem.

DR is a potential complication of diabetes. It occurs when high blood sugar in the body results in eye damage. Without treatment, this condition can lead to vision loss. There are two types of DR, which describe the severity of the condition and its potential effects on vision.

In this article, we will discuss the differences between nonproliferative and proliferative diabetic retinopathy.

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DR is an eye condition that is a common complication of diabetes. It occurs when high blood sugar levels damage the blood vessels within the retina. This part of the eye detects light and sends signals to the brain through a nerve in the back of the eye.

DR falls into two main classes: NPDR and PDR. NDRP refers to the early stages of the condition, while the latter describes the final and most severe stage.

The main difference between the two conditions is the presence of new, or proliferating, blood vessels. Health experts may use the term neovascularization to describe these blood vessels.

This term refers to new atypical blood vessels that grow from within the retina to the vitreous toward the center of the eye. The vitreous is the gel-like fluid present in the eye. These new and fragile blood vessels may leak fluid or cause scar tissue to form, which can lead to problems with vision.

Medical professionals typically classify DR into four stages depending on the progression of the condition. As the condition worsens, it advances through these stages. This includes three stages of NPDR and the most advanced stage, which is PDR.

The four stages include:

  • Stage 1 — mild NPDR: This is the earliest stage of the condition, where a person may not notice any symptoms. The characteristic feature of mild NPDR is the presence of at least one tiny bulge in the retina’s blood vessels, known as a microaneurysm.
  • Stage 2 — moderate NPDR: As blood vessels continue to swell, a person may begin to notice symptoms such as blurry vision. An eye doctor will be able to identify multiple microaneurysms in the retina.
  • Stage 3 — severe NPDR: This is the most advanced stage of NPDR. To diagnose this stage, a doctor may use the 4-2-1 rule. This refers to:
    • bleeding being present in all four quadrants of the retina
    • venous beading appearing in two or more quadrants
    • the presence of atypical branching of blood vessels in at least one quadrant
  • Stage 4 — PDR: This is the final and most advanced stage of the condition. The clinical features of PDR are the growth of new, fragile blood vessels in the retina or the presence of blood in the vitreous cavity.

Learn more about the different stages of DR.

In the early stages of NPDR, a person may not experience any symptoms. However, others may begin to notice changes to their vision. This can include blurry vision and difficulty reading or seeing faraway objects.

As the condition progresses, people may experience symptoms such as:

  • seeing spots or floaters
  • having a dark or empty spot in the central vision
  • difficulty seeing at night

In the most severe cases, it can lead to vision loss. Evidence notes that DR is the leading cause of blindness in working-age adults.

Treatment options for DR typically depend on several factors, such as the severity of the condition and previous responses to prior treatments.

In the early stages of NPDR, a doctor may recommend closely monitoring a person’s eyes without intervening. Healthcare professionals call this approach watchful waiting. A doctor will recommend how often someone requires a comprehensive dilated eye exam, which is usually as often as every 2 to 4 months.

In more advanced cases of DR, a person will typically require one of the following treatment options:

  • Laser treatment: To help reduce swelling and damage in the retina, an eye doctor can use lasers to shrink the blood vessels and prevent leakage.
  • Anti-vascular endothelial growth factor injections: A doctor can inject these medicines into the eye, which also helps reduce swelling and slow vision loss.
  • Vitrectomy: This is a type of eye surgery that removes blood and scar tissue from the vitreous cavity of the eye and replaces the fluid to hold the retina in place.

An effective strategy to reduce the risk of DR is to manage diabetes. A healthcare professional may refer to this as managing the “ABCs” of diabetes. This refers to:

Typically, the most effective way for someone to manage their diabetes ABCs involves getting regular physical activity, following a nutritious eating pattern, and following their diabetes care team’s guidelines for using insulin or other diabetes medication.

DR, and other diabetic eye conditions, may initially develop without noticeable symptoms. As such, it is vital that a person living with diabetes attends annual eye exams regularly. A doctor can monitor eye health and detect conditions in the early stages when they are easier to treat and manage.

Learn more about diabetic eye screening.

In addition to the above methods, other strategies to help maintain eye health include wearing protective eyewear, practicing eye safety, and giving the eyes a rest from screen time.

There are two main classes of diabetic retinopathy: nonproliferative and proliferative diabetic retinopathy. The former describes the early stages of the condition, where blood vessels begin to swell. The other refers to the final and most severe stage of the condition. This is when new blood vessels develop in the retina, which can lead to severe vision problems, such as blindness.