Population Based Assessment of Prevalence and Causes of Vision Impairment in the North-eastern State of Tripura, India – The Tripura Eye Survey

ABSTRACT

Purpose:

To report the prevalence and causes of vision impairment (VI) in a population aged ≥40 years from a state-wide survey conducted in the northeastern state of Tripura, India.

Methods:

A population-based cross-sectional study was undertaken where a sample of 4500 people was selected using cluster random sampling methodology. A team comprising of an optometrist and field workers visited the households and conducted the eye examination that included visual acuity assessment, anterior segment examination including lens and fundus examination. VI was defined as presenting visual acuity <6/18 in the better eye and it included moderate VI (<6/18 to 6/60), severe VI (<6/60 to 3/60) and blindness (<3/60).

Results:

In all, 4109/4500 (91.3%) subjects were examined from 90 clusters. Among those examined, 49.1% were men and 39.6% had no education. The age and gender-adjusted prevalence of VI was 8.7% (95% CI: 7.8–9.6). The prevalence of moderate VI was 6.2% (95% CI: 5.5–7.0), Severe VI was 1.0 (95% CI: 0.7–1.3) and blindness was 1.5% (95% CI: 1.1–1.9). On applying multiple regression analysis, the odds of having VI were higher in older age groups and among women. Overall, cataract was the leading cause of VI (54.5%) followed by uncorrected refractive errors (39.6%).

Conclusions:

VI is common affecting nine out of every hundred people aged ≥40 years in the state of Tripura. Over 90% of which is due to avoidable causes such as cataract and uncorrected refractive errors. Provision of cataract surgery and spectacles may result in a substantial reduction in VI in Tripura.

KEYWORDS:

• Vision impairment
• cataract
• uncorrected refractive errors
• India
• RAVI
• rapid assessment survey

Acknowledgments

LVPEI gratefully acknowledges the support of National Health Mission (Drs. Sandeep Mahatme and Shailesh K Yadav), and the Principal Secretary, Mr. M. Nagaraju, Government of Tripura in planning the study. We are grateful to the IL&FS team led by Mr. Samit Banik. The efforts of the team of optometrists, Goutam Deb, Anitesh Debbarma, James Debbarma, Jayasree Dey and Jayanta Das deputed by National Health Mission for the data collection are gratefully acknowledged for their contribution to the study. We also thank the people of Tripura who have actively participated in the study.

Conflict of interest

None of the authors have any proprietary interests or conflicts of interest related to this submission

Financial support

This study was funded by National Health Mission, Government of Tripura and Hyderabad Eye Research Foundation, India.