Exploring The Association Between Oral Contraceptive Pills and Glaucoma

Oral Contraceptive pills or the Pill as known by many is a type of female contraception that is taken every day to prevent pregnancy. Oral Contraceptives exist in different types including the oestrogen containing pill, the progestogen only pill and the combined pill which contains both the oestrogen and the progestin. Both the oestrogen and progestin hormones works by stopping the eggs from being made thus preventing the release of the eggs from the ovary. However, the pill has some side effects which could be ocular or systemic. Studies found that there is a link between the long term use of oral contraceptives and eye health.

It is a long known fact that there is some sort of association between female sex hormones and IOP changes. Oral contraceptive contains artificial oestrogen and progestin. Oestrogen is said to be a cause for decline in the IOP and therefore a decrease in the risk of the development of open angle glaucoma when taken in by females as a hormone replacement therapy in postmenopausal females. Past studies suggested that an oestrogen-deficient state result in a raised deterioration of the optic nerve, which eventually develop into glaucoma. The outflow facility is influenced by both oestrogen and progestin and they play a role in the regulation of IOP.

The news that there is a reported association between oral contraceptive pills and glaucoma made a disturbance in the media and on the internet when researchers at the Ophthalmology Academy’s 2013 annual meeting presented the report. The exploration in question establish that females who took oral contraceptives (OCs) for a period of three years and further had more risk of developing primary open-angle glaucoma (POAG) late in life.

However while the media played up the story, one of the co-authors, Shan Lin, MD, at the University of California, San Francisco, highlighted that additional studies are necessary to confirm the findings, which were grounded on patients’ self-report of a glaucoma diagnosis.

Scientists have noted that there are several different formulations of oral contraceptives; some comprise progestin only, which suppresses oestrogen as stated in the first paragraph. However even oral contraceptives that comprise oestrogen comprise just sufficient to destroy ovulation, which then alters the monthly hormonal patterns.

Furthermore, the formulations have altered ever since the first oral contraceptive was accepted in 1960, with the early generation containing greater levels of oestrogen than existing forms. Whether the changes in formulation over time have affected glaucoma risk is still an on-going study by Dr. Kang. 

It seems as if scientists are gathering proof to sustain the theory that the going oestrogen may play a significant role in the pathogenesis of glaucoma bit by bit. They theorized that reduced exposure to oestrogen adds to increased vulnerability of the optic nerve to glaucomatous damage and that oestrogen may provide a shielding consequence against glaucoma. 

In the 2000s a burst of studies discovered risk relations between numerous reproductive factors and glaucoma. These studies were made of early menopause, late menarche, oophorectomy, and most lately, oral contraceptive use. Some studies have found protective effects from late menopause or hormone replacement therapy.

The mechanism of oestrogen’s protective effect remains uncertain, nonetheless most of the proof proposes that it could be neuroprotective, said Dr. Lin. He gave details that oestrogen receptors are expressed in a selection of ocular tissues, as well as the retinal ganglion cells (RGC), where oestrogen seems to have a maintenance effect.

A single systematic theory holds that oestrogen triggers the synthesis of collagen fibre, accumulating the amount of collagen fibre at the lamina cribrosa, as a result cultivating the structure’s compliance. This could relieve compression on retinal ganglion cells axons, aiding in their survival. The doctor said that enlarged collagen fibre also possibly will boost flexibility of the entire eye, which would lead to a decline in IOP.

We know that early loss of oestrogen is associated with increased risks of a variety of health outcomes, including several conditions related to brain aging,” Dr. Vajaranant said. “We also know that the major risk factor for glaucoma is advanced age. Therefore, one possibility is that an early loss of oestrogen causes the optic nerve to age prematurely and predisposes the optic nerve to glaucomatous damage.

Recent reports are saying that there is an increased risk of glaucoma in females on oral contraceptive pills. The reports attempt to answer the question which was raised by researchers in the previously as to what exact role does oestrogen and progesterone play in the pathogenesis of glaucoma. Studies show that women taking oral contraceptives pills for a period longer than 3 years are more likely to develop glaucoma as compared to the women who are not on the pills.

In America it is estimated that about 11 million and more women at present are using birth control pills to prevent pregnancy, whereas hormone replacement therapy is commonly used to regulate the symptoms of menopause. And the question researchers are asking is “did you know that their use may also cause a variety of side effects that includes dry eye and glaucoma, both of which can lead to poor vision or even vision loss?

The use of oral contraceptives pills is associated with eye health. One of the most common grievances for women taking birth control pills or hormone replacement therapy is dry eye, a common and often chronic condition in which there is not enough tears to lubricate and nourish the eye well. A well-known cause of dry eye is hormonal variations, which can be conveyed about by using birth control or hormone replacement. According to the National Eye Institute, women who take estrogen-only hormone replacement therapy are 70 percent more expected to grow dry eye, whereas women using both estrogen and progesterone convey a 30 percent increased chance of emerging dry eye.

By means of logistic regression models, and changing for prospective confounders, they found that woman who had used oral contraceptives, no matter which kind, for longer than three years, were two times more likely to report that they have expected a diagnosis of glaucoma.

Oestrogen has been linked to glaucoma more than once by researchers across the world. An earlier report in the British Journal of Ophthalmology connected the early menopause to a bigger threat of primary open angle glaucoma (POAG), and later age menopause commencement with a decreased risk of Primary Open Angle Glaucoma. Moreover, a prospective cohort study of generative factors and the jeopardy for primary open angle glaucoma as part of the Nurses’ Health Study, presented a 25 present enlarged risk of incidence of primary open angle glaucoma in women who used oral contraceptives longer than five years.

The potential reason behind this increased risk could be the fact that these oral contraceptive pills lead to pulling down of estrogen levels in the bodies of the females getting them, consequently abolishing the normal peak and trough pattern of the estrogen levels, leading to a effective estrogenlacking state.

Nonetheless, the exact relation between these hormones and the risk of open‑angle glaucoma needs to be considered further, and this can be successfully achieved by combining a proper pharmacovigilance program. The physicians prescribing oral contraceptive pills together with the patients receiving them need to be made aware of the coexisting risk of open‑angle glaucoma, so that any slight change in intraocular pressure is reported, to reveal any association between the use of oral contraceptive pills and the future glaucoma risk, if any

Some scientist and doctors are saying that it is too early to make recommendations about contraceptive use and risk for glaucoma, but they suggest that any woman older than 40 who uses the pills should be screened for glaucoma and have their eyes examined by an ophthalmologist. The outcome of the examination will help with further research and help improve eye health.

While the study shows an association, not relationship, a British researcher Dr. Lin suggests that oral contraceptive use could be considered as part of the risk outline for glaucoma, along with other standing risk factors. His study was a cross-sectional study including 3,406 women age 40 and older, from the 2005-2008 The National Health and Nutrition Examination Survey. The women finished a vision and multiplicative health questionnaire and undertook eye exams.

Dr. Lin does not recommend that patients should be advised to discontinue oral contraceptives built on his study. But then they ought to be warned to have their eyes screened if they have a history of long-term oral contraceptive practice, along with other risk factors such as African American origin, family history of glaucoma, or history of increased IOP or current visual field deficiencies. Eventually, longitudinal studies and paired blinded clinical trials are necessary to notice any contributing effect of longer term oral contraceptive use on the threat of glaucoma.

Scientists cautioned that the Pill might play a role in glaucoma and advised women at risk to have their eyes screened. Glaucoma is triggered by an accumulation of fluid pressure in the eye, causing an endless damage to the optic nerve. The most common, chronic form of the disease is thought to distress about 480,000 people in the United Kingdom.

Earlier studies have proposed that the hormone oestrogen, an important element of the Pill, may be complicated in the growth of glaucoma. At the American Academy of Ophthalmology's yearly summit in New Orleans, new discovery was presented following a study of 3,406 females aged 40 and above who were asked about their reproductive history and endured eye examination.

Even with the well-known publicity, as well as the common use of oral contraceptives, a lot of females are questioning their ophthalmologists about the potential risks. Taking a step back and looking at the more perspective of what current research is saying about the part oestrogen play in glaucoma could help in replying to patients’ fears.

Studies have shown that the rising proof of the impact of female sex hormones on glaucoma proposes that there are distinctive, risk factors that are specific to sex hormones that result in glaucoma in females, such as premature menopause and the usage of female hormones. We as eye care specialist together with doctors ought to be conscious of these risks and propose suitable recommendations and management for our patients. Having a better understanding of sex hormones alterations that disturb eye diseases is what eye care specialist need when caring for their patients.

In conclusion, the association of Oral Contraceptives with raised IOP should be a concern to the World Health Organization as it is a risk factor for glaucoma, the second leading cause of blindness in the world. Health care practitioners need to explain the effect of the long use of the Pill to the population as it seems most women are not aware of the oncoming risks of taking the pills. Women taking Oral Contraceptive Pills should be encouraged to have routine eye examination with the eye specialist at least yearly for monitoring their IOP changes so that the risk of developing glaucoma is reduced.

References

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