MALAYSIANS are no strangers to high blood pressure as according to a survey in 2024, one in three adults in this country lives with hypertension.
Most have heard that high blood pressure can cause heart attacks and strokes but far fewer people realise hypertension can also damage your eyes at the exact same time.
So, is it true that your blood pressure actually ruin your eyesight?
Verdict:
TRUE
High blood pressure can cause serious, permanent damage to the eyes, and the truly alarming part is that it can do so completely silently, without any warning signs, until it is too late.
To understand why, it helps to know what the eyes actually need to function.
The retina, the thin layer of tissue at the back of the eyeball that converts light into the images the brain can see, depends entirely on a network of tiny blood vessels to keep it alive and working.
When blood pressure is too high for too long, those blood vessels take a beating.
The force of the blood pushing against the vessel walls causes them to narrow, thicken and stiffen over time, restricting the flow of blood to the retina.
Without enough blood flow, parts of the retina start to deteriorate, leading to a condition called hypertensive retinopathy, which is essentially the medical term for eye damage caused by high blood pressure.
A peer-reviewed review published in the US National Institutes of Health's research database described hypertensive retinopathy as a progressive and painless condition, meaning it got worse gradually and the person experiencing it often felt nothing until the damage was already done.
The American Heart Association noted that the condition could cause blurred vision, distorted vision and in severe cases complete loss of sight, and that managing blood pressure was the only way to treat it.
High blood pressure caused eye damage in three main ways.
First, restricted blood flow damaged the retina directly, leading to vision deterioration.
Second, fluid could build up under the retina, distorting vision in a condition called choroidopathy.
Third, blocked blood flow could damage the optic nerve, the cable that carried visual information from the eye to the brain, killing nerve cells and causing permanent vision loss in a condition called optic neuropathy.
A peer-reviewed study published in Scientific Reports examining the relationship between blood pressure and eye pressure found that high blood pressure was directly associated with elevated pressure inside the eyeball, a key risk factor for glaucoma, one of the leading causes of irreversible blindness worldwide.
Research published in the US National Institutes of Health's research database also found that people who had experienced hypertensive retinopathy had a 35% higher risk of stroke in its milder form, rising to a 137% higher risk in moderate and severe cases, reinforcing just how closely the eyes reflected the health of blood vessels throughout the entire body.
This was actually one of the reasons eye doctors played an important role in detecting undiagnosed high blood pressure.
Because the retina was the only place in the human body where blood vessels could be directly observed without surgery, a routine eye examination could reveal early signs of blood vessel damage long before a person noticed any symptoms elsewhere.
The National Health and Morbidity Survey 2023 found that 6.7 million Malaysians, or roughly one in three adults, had hypertension, and nearly 12% of the population did not know they had it.
Hypertension was well established as a silent condition with no obvious symptoms, and for many Malaysians the first sign of trouble came only when complications, whether a heart attack, stroke or in this case vision problems, had already set in.
The good news was that hypertensive retinopathy was largely preventable and, if caught early enough, manageable.
Keeping blood pressure within a healthy range through medication, a lower sodium diet, regular exercise and cutting back on alcohol significantly reduced the risk of damage to the eyes and every other organ the condition threatened.
For Malaysians who had not had their blood pressure checked recently, the time to do so was well before the eyes started showing the consequences.
Sources:
1. https://pmc.ncbi.nlm.nih.gov/articles/PMC8790937/
2. https://pmc.ncbi.nlm.nih.gov/articles/PMC10597370/
3. https://pmc.ncbi.nlm.nih.gov/articles/PMC9640608/
4. https://www.nature.com/articles/s41598-022-22301-1
6. https://my.clevelandclinic.org/health/diseases/25100-hypertensive-retinopathy
