Ocular hypertension, or high pressure in the eye, is a risk factor for glaucoma, a condition that can cause irreversible blindness if left untreated. People with ocular hypertension may not experience any symptoms, but it is important to monitor eye pressure regularly and seek treatment if necessary.
The only known treatment to prevent or interrupt glaucoma is to lower high eye pressure. However, not everyone with ocular hypertension needs to be treated. A major long-term study, called the Ocular Hypertension Treatment Study (OHTS), has provided some insight into who may need treatment for ocular hypertension.
According to the OHTS, people with ocular hypertension have a 4-5% chance of developing glaucoma each year. However, not all people with ocular hypertension will develop glaucoma, and some people with normal eye pressure may develop glaucoma.
Your ophthalmologist will monitor your eye pressure, as well as other risk factors, such as the appearance of your optic nerve, to determine if treatment is necessary. In summary, not all people with ocular hypertension need treatment, but regular monitoring of eye pressure is essential to determine whether treatment is necessary to prevent or interrupt the progression of glaucoma.
Does everyone with high eye pressure develop glaucoma?
The OHTS study also found that certain risk factors, such as older age, African American race, and a family history of glaucoma, were associated with a higher risk of developing glaucoma. Additionally, the study found that people with thinner corneas, or a greater difference in eye pressure between the two eyes, were also at a higher risk.
It's important to note that the OHTS study was conducted on a specific group of people with ocular hypertension and may not be generalizable to all people with high eye pressure. However, the study does provide valuable information for ophthalmologists to consider when determining if someone with ocular hypertension should start medication to prevent glaucoma.
In conclusion, ocular hypertension is a risk factor for glaucoma, and regular eye exams are essential to monitor eye pressure and detect the early signs of glaucoma. The OHTS study shows that early use of medicated eye drops can help delay the development of glaucoma in people with ocular hypertension, and that certain risk factors such as age, race, and family history should be taken into consideration when determining the need for treatment.
Who took part in the study?
In the OHTS study, a high proportion of participants (25%) were Black, which is significant because minorities have traditionally been underrepresented in clinical trials. The remaining participants were mostly white. The ages of participants ranged from 40 to 80 years (the average age was 55). Apart from ocular hypertension, all participants had normal eye exams, normal vision, and eye anatomy known as open angles, and none of them had pre-existing glaucoma.
It's important to note that the study population was specifically chosen to have ocular hypertension, a risk factor for glaucoma, and not to have glaucoma yet. The study results provide valuable information for people with ocular hypertension, but it's important to remember that the results may not be generalizable to all people with ocular hypertension or glaucoma.
This study is important because it gives insight into the treatment of ocular hypertension and the development of glaucoma, particularly among minority populations. It also highlights the importance of regular eye exams to monitor eye pressure and detect the early signs of glaucoma.
In conclusion, the OHTS study provides valuable information for people with ocular hypertension and their ophthalmologists to consider when determining if treatment is necessary to prevent glaucoma. The study also highlights the importance of including a diverse population in clinical trials to ensure that the results are generalizable to all populations.
Has this research changed thinking on when to start treating glaucoma?
At first glance, the five-year data from the OHTS study suggested that Black individuals had a higher rate of glaucoma than people of other races. However, this apparent difference disappeared when the researchers controlled for important characteristics such as age, thickness of the cornea, a measure called optic nerve cup size, and initial peripheral vision test scores.
This finding highlights that glaucoma risk is not solely determined by eye pressure and race, but by a combination of exam findings. This information can help guide clinicians in determining whether a person with ocular hypertension is at a low, medium, or high risk for developing glaucoma.
Having this information is crucial for people with ocular hypertension as it can help them decide when to begin using medicated eye drops to prevent vision loss or slow its progression. It also emphasizes the importance of regular eye exams and the need to consider other factors beyond eye pressure and race when determining glaucoma risk.
In conclusion, the OHTS study showed that risk of developing glaucoma among people with ocular hypertension is not solely determined by eye pressure and race, but also by a combination of other factors such as age, corneal thickness, optic nerve cup size, and initial peripheral vision test scores. This information is essential for clinicians and patients to make informed decisions about treatment options and to prevent vision loss.
What are the limitations of this long-term study?
The OHTS study has several limitations that should be considered when interpreting the results:
- Trial participants usually comply better with medications and appointments than those not participating, which might make real-world rates of glaucoma higher than what occurred with either group in the study.
- During later phases of the study, both groups could receive eye pressure-lowering medications. By 20 years, most participants were using these medications: about 81% in the medication group and 66% in the control group. This makes it difficult to compare the long-term effect of each starting approach.
- Glaucoma detection has improved over the years, with new diagnostic tests such as ocular coherence tomography and newly discovered risk factors such as corneal hysteresis. This may further support watchful waiting as a reasonable option for people at lower risk for glaucoma based on a combination of factors.
- The results of the study do not apply to those who already have glaucoma or other eye diseases, and the eye anatomy known as narrow angles.
It's important to note that the OHTS study was conducted on a specific group of people with ocular hypertension and may not be generalizable to all people with high eye pressure. However, the study does provide valuable information for ophthalmologists to consider when determining if someone with ocular hypertension should start medication to prevent glaucoma.
What’s the bottom line?
Overall, the 20-year follow-up data from the OHTS study supports the decision-making process of preventive glaucoma therapy for people with ocular hypertension based on a combination of additional exam findings. People with a higher number of risk factors such as older age, thinner corneas, larger optic nerve cup sizes, and worse initial peripheral vision test scores are more likely to develop glaucoma.
If you have ocular hypertension and several other risk factors, eye pressure-lowering eye drops or a brief office procedure known as selective laser trabeculoplasty can help prevent glaucoma. If you have ocular hypertension and fewer additional risk factors, you can likely delay treatment if you receive regular exams to detect early signs of glaucoma. However, it's important to remember that glaucoma is an often silent condition, and anyone who has ocular hypertension should receive lifelong monitoring regardless of treatment status.
It's important to work closely with your ophthalmologist to determine the best course of treatment for you. They will take into consideration your individual risk factors, as well as your preferences, to create a personalized treatment plan that is right for you.
In summary, the OHTS study provides valuable information for people with ocular hypertension and their ophthalmologists to consider when determining if treatment is necessary to prevent glaucoma. It also emphasizes the importance of regular eye exams, early detection and management of glaucoma, and considering other factors beyond eye pressure and race when determining glaucoma risk.