Diabetes and your eyes

What this article covers

What actually happens inside the eye with diabetes?
Can you lose sight without any warning?
When to start eye examinations and how they work
The grades of retinopathy and what they mean
How retinopathy is treated
Blood sugar and blood pressure: the core prevention
Warning signs that need same-day assessment
Questions to ask at your retinal screening appointment

What actually happens inside the eye with diabetes?

The retina is the light-sensitive layer at the back of the eye, nourished by a network of tiny blood vessels. Chronically elevated blood glucose progressively weakens the walls of these vessels, causing them to leak, swell, or bleed inside the retina. This is diabetic retinopathy.

The early stage is called non-proliferative diabetic retinopathy. It is characterised by small bulges in vessel walls called microaneurysms, and may include small haemorrhages or fatty deposits called hard exudates. At this stage the person usually notices nothing different about their vision, which is why the condition is so easily missed without formal screening.

If blood sugar and blood pressure remain uncontrolled, the disease can progress to proliferative diabetic retinopathy, where the retina responds to oxygen deprivation by growing new, fragile, abnormal blood vessels across its surface. These new vessels bleed easily and can cause vitreous haemorrhage or traction retinal detachment, both of which can result in sudden severe vision loss.

Can you lose sight without any warning?

Yes, and this is what makes retinopathy uniquely dangerous. The retina does not feel pain when it is damaged, and the peripheral areas are affected before the centre, so many people maintain apparently normal vision while significant damage accumulates. By the time a person notices a change in their eyesight, the disease may have been progressing silently for years.

A landmark 2012 systematic review in Diabetes Care found that approximately 34.6 percent of people with diabetes have some degree of retinopathy, and that duration of diabetes, high HbA1c, and raised blood pressure are the strongest predictors. This tells us that the risk is widespread and often underestimated by people who feel well.

A cross-sectional study of diabetic patients in the United Arab Emirates, published in BMC Ophthalmology in 2007, found that retinopathy rates in the region are significant and that many cases were detected late. A 2025 systematic review found that diabetic retinopathy is among the leading causes of severe visual impairment and blindness across Arab countries. These findings confirm that for people in this region, the threat is real and the consequences of missed screening are serious.

When to start eye examinations and how they work

For type 2 diabetes: start retinal screening at the time of diagnosis. Many people with type 2 diabetes have had elevated blood sugar for years before it is discovered, and changes may have already developed. For type 1 diabetes: the standard recommendation is to begin retinal screening five years after diagnosis. For pregnant women with pre-existing diabetes: an eye examination at the start of pregnancy and at intervals through it is recommended, as pregnancy can accelerate existing retinopathy.

The standard examination involves dilating the pupil with eye drops and photographing the retina, or examining it directly with a slit lamp. This is painless, though your vision will be blurred for a few hours afterwards, so you should not drive. Retinal photography without dilation is now widely available and is the backbone of community screening programmes in many countries.

A comprehensive 2020 review in the Lancet Diabetes and Endocrinology confirmed that structured retinal screening programmes demonstrably save sight, and that expanding digital retinal photography into community and primary care settings, including areas without specialist eye units, is now technically achievable. If your clinic offers photograph-based screening, use it.

If no specialist centre is nearby, ask your doctor whether digital retinal photography is available at your primary care facility. Some programmes across the region have integrated this into routine diabetes follow-up. If that is not yet available where you are, ask for a referral to the nearest centre that does provide it, and budget for an annual visit even if it requires travel.

Recommended eye examination schedule for people with diabetes

At diagnosis (type 2) First retinal examination at the time of diagnosis
Annually Routine retinal check if previous results were normal
Every 6 months If mild or moderate non-proliferative retinopathy is found
Every 3 months or per specialist If advanced or proliferative retinopathy, or macular oedema
Start of pregnancy For women with pre-existing diabetes: check at booking and every trimester

The grades of retinopathy and what they mean

Retinopathy is not a single condition but a spectrum. Mild non-proliferative disease means small vascular changes with no impact on useful vision. Improved blood sugar and blood pressure control at this stage can slow or arrest progression. Moderate non-proliferative disease involves more widespread vascular changes and some tissue damage, and monitoring becomes more frequent.

Diabetic macular oedema (DMO) deserves particular attention because it can occur at any stage, including in mild non-proliferative disease. It involves fluid accumulating in the macula, which is the central part of the retina responsible for sharp, detailed vision. A person with DMO may notice distortion or blurring of central vision while reading or looking at faces, even when their retinopathy is otherwise still at an early grade. This is a priority for treatment.

Proliferative diabetic retinopathy is the advanced stage where new abnormal vessels grow across the retinal surface and into the vitreous gel. These vessels are fragile, and when they bleed the person may suddenly see dark spots, threads, or a red haze across their vision. This is a medical emergency. Retinal detachment from the tractional pull of these vessels is also possible and requires urgent surgical intervention.

Grades of diabetic retinopathy at a glance

Grade	What is happening	Management approach
Mild non-proliferative	Microaneurysms only	Better glucose and BP control, annual check
Moderate non-proliferative	Haemorrhages and exudates	6-monthly review, tighten control
Severe non-proliferative	Widespread vessel closure	3-monthly review, laser may be needed
Proliferative	Abnormal new vessel growth	Laser or injections, close follow-up
Macular oedema	Fluid at centre of retina	Anti-VEGF injections, high priority

How retinopathy is treated

Treatment depends on the grade. In early stages, the primary intervention is improving blood sugar and blood pressure control. Research consistently shows that this alone measurably slows the disease even when retinopathy is already present. There is no medication that reverses existing retinal damage, but good metabolic control substantially reduces the risk of worsening.

For more advanced disease, laser photocoagulation has been the standard treatment for decades. It seals leaking vessels and destroys ischaemic retinal tissue that drives the growth of abnormal vessels. Anti-VEGF injections directly into the eye, drugs that block the abnormal vessel growth signal, have become the primary treatment for macular oedema and are also used in proliferative retinopathy. They are administered with anaesthetic drops and cause minimal discomfort.

Vitrectomy surgery is required when vitreous haemorrhage is dense or when retinal detachment occurs. This is a specialist procedure performed by a vitreoretinal surgeon and requires referral to a centre with the appropriate expertise. In the event your vision changes suddenly, ask whether the nearest emergency eye unit has vitreoretinal surgical cover, as time to surgery matters in these situations.

Blood sugar and blood pressure: the core prevention

The large clinical trials are unambiguous: tighter blood sugar control measurably reduces both the incidence and the rate of progression of diabetic retinopathy. The Diabetes Control and Complications Trial in type 1 diabetes and the UK Prospective Diabetes Study in type 2 both showed that reducing HbA1c by one percentage point produces significant reductions in microvascular complications including retinopathy. This evidence directly justifies the effort of managing diabetes carefully.

Blood pressure is an independent factor. Raised blood pressure damages the delicate retinal vessels regardless of glucose level. The target blood pressure in diabetes is generally below 130/80 mmHg. ACE inhibitors and angiotensin receptor blockers (ARBs) are often the preferred antihypertensive agents in diabetes because they also protect the kidneys, and some evidence suggests additional retinal benefit.

Blood lipid levels, particularly raised triglycerides and LDL cholesterol, are associated with the severity of hard exudates in the retina and with macular oedema. Managing lipids through diet, exercise, and medication when indicated is part of a complete eye protection strategy, not just cardiovascular prevention.

Smoking is an independent risk factor for diabetic retinopathy and accelerates its progression in people who already have it. If you smoke and have diabetes, stopping smoking is one of the most protective actions you can take for your eyes, kidneys, and cardiovascular system simultaneously. There is no safe level of smoking for someone with diabetes.

Warning signs that need same-day assessment

Any sudden change in vision in a person with diabetes should be treated as an emergency until proven otherwise. Do not wait for a routine appointment. Contact your eye clinic directly or go to the nearest emergency eye service the same day.

Sudden floaters, which are small dark spots, threads, or cobwebs appearing in the visual field, or flashes of light in one eye, may indicate vitreous haemorrhage or retinal traction. These symptoms in a person with diabetes justify urgent assessment even if vision seems only mildly affected at the time, because the situation can worsen rapidly.

Distortion of straight lines, a dark patch at the centre of vision, or a sudden drop in the sharpness of your central vision may indicate macular oedema or haemorrhage at the macula. Acting quickly at this stage makes a substantial difference to what can be preserved. A curtain or shadow blocking part of the visual field suggests retinal detachment, which is a surgical emergency.

Questions to ask at your retinal screening appointment

At each retinal check, ask your screener or ophthalmologist: what grade of retinopathy, if any, do I have? Is there any macular oedema? When should I return for my next check? Is there anything I should do differently to protect my eyes before then? These questions turn a passive appointment into a useful conversation and ensure you leave with an accurate understanding of where you stand.

Share the retinal screening result with your diabetes doctor if they are not the same person. The finding of even mild retinopathy may prompt a review of your HbA1c target, blood pressure management, or lipid levels. Coordinated care between the eye team and the diabetes team produces better outcomes than each working in isolation.

If you live far from a specialist eye centre, discuss with your diabetes doctor or general practitioner what the pathway is if you need urgent eye assessment. Knowing the answer before an emergency arises, including which hospital to go to and how to present as an urgent case, removes delay at a time when delay matters most.

Log your retinal screening dates and results in the Sihtak app alongside your blood sugar readings, so you arrive at every appointment with a complete picture and never miss a scheduled check.

Frequently asked questions

Can I have retinopathy without noticing any change in my vision?

Yes, and this is the central reason why regular eye examinations are essential for everyone with diabetes. Early and moderate grades of retinopathy produce no pain and no obvious vision change. The damage becomes visible to the ophthalmologist on the retinal photograph long before the person notices anything themselves.

Does normal vision mean my retina is healthy?

Not necessarily. The retina has no pain receptors and peripheral vision is affected before central vision, so many people with significant retinal damage still feel they see normally. Only a retinal examination or photograph reveals the true state of the retina.

Is good blood sugar control enough to protect my retina?

It is the single most important factor, but blood pressure and lipids also matter independently. Duration of diabetes is a cumulative risk: even with good control, the risk rises over years. This is why annual screening remains necessary even for people with excellent blood sugar management.

Does laser treatment hurt, and can it restore lost vision?

Laser treatment is performed with anaesthetic eye drops and is not painful, though there may be mild discomfort after the session. Its goal is to halt progression and preserve the vision that remains, not to restore what has already been lost. This is precisely why acting early, while vision is still good, gives the best outcome.

Can children and young people with diabetes develop retinopathy?

Yes, especially those with type 1 diabetes diagnosed in childhood. Duration of disease is the main cumulative risk factor. Screening from five years after diagnosis, or at puberty if earlier, is the standard recommendation for type 1 diabetes regardless of age.

Can pregnancy worsen diabetic retinopathy?

Yes, pregnancy can accelerate existing retinopathy, which is why eye examination at the start of pregnancy and at intervals through it is recommended for women with pre-existing diabetes. Gestational diabetes that develops during pregnancy for the first time is not associated with the same risk.

Are specialist retinal services available across the Arab world?

Major cities in Saudi Arabia, the UAE, Egypt, and Jordan have retinal specialist centres offering laser treatment, anti-VEGF injections, and vitreoretinal surgery. Availability is much more limited in smaller towns and rural areas. It is worth asking your diabetes doctor now, before a problem develops, which facility you would be referred to for urgent eye care.

Sources

This content is for health education only and is not a substitute for medical advice. If you have symptoms that worry you, see your doctor.