• Researchers' study found that acupuncture across four weeks leads to favourable changes in protein levels in tear fluids
  • Clinical trial by Singapore Eye Research Institute and Chung Hwa Medical Institution to recruit peri- and post-menopausal women to evaluate efficacy of herbal remedies in treating dry eye


Singapore, 28 March 2022 – A recent study by the Singapore Eye Research Institute (SERI) and the Singapore Chung Hwa Medical Institution (SCHMI) found that acupuncture can alter the levels of proteins secreted in tear fluids. This can benefit patients who suffer from mild to moderate dry eye disease. The findings are the latest in dry eye research by the two collaborating institutions, and further suggest that Traditional Chinese Medicine (TCM) can pave the way for managing the condition.


12% of Singapore's population suffer from dry eye disease, and 90% of these patients have mild to moderate cases. Dry eye disease is caused by the lack of adequate tears, which is crucial in keeping the eye surface healthy. Symptoms include redness or irritation of the eye, sandy or gritty sensation in the eye, or blurry vision. Dry eye, in its less severe form, is commonly controlled using over-the-counter medication and lubricants like eye drops and eye gels.


"Majority of dry eye patients in Singapore have them in the mild to moderate form. It is thus worth considering treating this group of patients in the primary care settings and by exploring and focusing on holistic treatments like TCM, to help them keep cost and care affordable and to prevent their condition from worsening, as this group of dry eye patients tend to be associated with systemic conditions, and not just local dry eye deficiency alone," said Dr Pat Lim, Head, TCM Ophthalmology Department, Chief Physician and Board Vice Chairman at SCHMI and the Principal Collaborator for this study. "With the previous successful research studies we have conducted, and scientific evidence from the studies, we are able to standardise and develop acupuncture and herbal prescriptions like Qi Ju Gan Lu Yin (杞菊甘露饮) that can provide better therapeutic effects for dry eyes condition."


Favourable tear protein changes with acupuncture

The acupuncture study compared 15 dry eye participants who used a lubricating eye gel together with eight acupuncture sessions over four weeks (variable group), and another 15 dry eye participants who used only the eye gel (control group). Nine out of 15 participants (60%) in the variable group were examined to have an increase in supportive proteins and a decrease in inflammatory proteins. On the other hand, only four out of 15 participants (27%) in the control group showed equivalent patterns of protein change.


This study, together with an earlier one conducted in China, suggests that acupuncture does not simply stimulate a reflex irritation of the tear fluid, because that tends to change the tear volume without inducing a beneficial alteration of the alteration of the tear film. This is particularly of interest to the researchers because dry eye is most commonly a defect in the components of the tear rather than insufficient tears.


Researchers explore more benefits TCM can bring to dry eye patients

With the encouraging findings from the acupuncture study, the researchers are also embarking on exploring the efficacy of herbal remedies – another aspect of TCM – on dry eye for peri- and post-menopausal women with Liver-Kidney yin deficiency[1]. This will be carried out via a 12-week randomised-controlled clinical trial.


Compared to the rest of the population, peri- and post-menopausal women have a higher incidence of dry eye disease. Studies done in the United States have shown that the rate of dry eye disease in women over 50 years old is nearly double (7%) that in men over 50 years old (4%). Studies suggest that this could be due to the hormonal changes experienced by women during and after menopause.


"We see a significant number of peri- and post-menopausal women who are very symptomatic at our dry eye clinic. About 70% of patients are women and more than half are above 55 years old. Such patients are not likely to benefit from conventional prescription drugs for dry eye, such as cyclosporine and corticosteroids. Hormonal replacement therapy for menopausal women is not yet universally accepted and carry risks. Topical hormonal therapy for dry eye is also not widely available and still controversial. We see an opportunity to employ new therapeutic modalities, such as TCM, to treat dry eye in these women," said Professor Louis Tong, Principal Clinician Scientist & Head of the Ocular Surface Research Group, Singapore Eye Research Institute, and Senior Consultant, Corneal & External Eye Disease Department, Singapore National Eye Centre.


Mr Liew Siaw Foo, Board Chairman of SCHMI also shared, "The last research study in 2015 to 2017 was a successful collaboration between SERI and SCHMI. We would also like to thank the Ministry of Health (MOH), Traditional Chinese Medicine Research Grant for funding these two studies on dry eyes research. These valuable experiences in research collaboration and knowledge of conducting scientific studies have benefited us. It has encouraged our research team to conduct more rigorous TCM research in future."


From 01 March 2022 to 31 August 2023, the clinical trial is recruiting 150 peri- and post-menopausal women between 40 to 79 years old, who have dry eye symptoms like eye irritation, burning, or watering. For enquiries to participate, members of the public can email SERI's research office at res.recruit@seri.com.sg or contact SCHMI at +65 6877 4203 / +65 8424 0546 (9.00am to 5.00pm, Mondays to Saturdays).


[1] Liver-Kidney yin deficiency refers to one pattern differentiation categorized under systemic health, which is mainly characterised by dry eyes, anxiety, hot flush, night sweats, dry skin, warm palms and soles, knee and back soreness and ache and etc.