Population-Based Study of Presbyopia in Rural Tanzania

doi:10.1016/j.ophtha.2006.01.030

Ophthalmology

Volume 113, Issue 5, May 2006, Pages 723-727

https://doi.org/10.1016/j.ophtha.2006.01.030 Get rights and content

Objective

To determine the prevalence of presbyopia in a rural African population.

Design

Cross-sectional prevalence study.

Participants

One thousand seven hundred nine persons age 40 years and older who resided in 3 villages and randomly selected neighborhoods of Kongwa town, Tanzania.

Methods

Eligible persons were refracted and given best distance correction. Near vision was tested and corrected to the nearest 0.5 diopter. Presbyopia was defined as at least 1 line of improvement on a near visual acuity chart with an addition of a plus lens.

Results

A total of 61.7% of eligible participants were presbyopic. A higher prevalence of presbyopia was associated with increased age, female gender, higher educational level, and residence in town (odds ratio = 3.09; 95% confidence interval: 2.46–3.90). The odds of developing presbyopia increased 16% per year of age from age 40 to 50, but the increase was nonsignificant at 1% per year after age 50. More severe presbyopia was associated with female gender and less with education.

Conclusions

This study provides the first population-based data on prevalence of presbyopia in a large, random sample of older Africans and suggests a high rate of presbyopia. Presbyopia plateaus after age 50, and it is more common in females. In addition, the 3-fold increased odds in town versus village dwellers was unexpected and suggests that research of other factors, including environmental factors, is warranted.

Section snippets

Subjects and Methods

The Tanzania Near Vision Impairment Project is a population-based study of adults, 40 years of age and older in Kongwa, Tanzania. Kongwa is a rural district in central Tanzania, consisting of 44 villages whose residents are largely herders and subsistence farmers. The town of Kongwa is the district center, consisting largely of small shopkeepers. The district hospital has primary eye care services but no optical services.

The study population was a sample of village and town residents in the

Results

Of the 2040 persons eligible for screening, 1709 (83%) participated. Table 1 shows characteristics of the sample stratified by participation status. Compared with participants, nonparticipants were more likely to belong to either the youngest or oldest age category (χ²₍₅₎ = 18.0; P = 0.003). Participation rates were higher in females than males (age-adjusted P = 0.012). There was no difference in participation rates between the Kongwa town and the 3 villages.

Of the 1709 participants, 120 (7%)

Discussion

The present study provides the first population-based data on prevalence of presbyopia in a large, random sample of older Africans. Results indicate a 61.7% prevalence of presbyopia among adults age 40 and older in rural Tanzania. The only other population-based study of presbyopia in Africans examined a small sample of Nigerians (18 to 49 years of age) and found a prevalence of 33%, although the methods for defining presbyopia were not well described.³ One additional study, based on a

Acknowledgments

The authors thank Dr Matt Lynch for his assistance in the field, Dr Paul Courtright for facilitating the acquisition of spectacles, and Dr Velma Dobson for her help with the manuscript.

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Manuscript no. 2005-565.

This work was supported by Alcon Research Institute, Fort Worth, Texas (unrestricted grant to SKW), which had no role in this project.

Dr West is a senior scientific investigator for Research to Prevent Blindness.

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Original ArticlePopulation-Based Study of Presbyopia in Rural Tanzania

Objective

Design

Participants

Methods

Results

Conclusions

Section snippets

Subjects and Methods

Results

Discussion

Acknowledgments

Surv Ophthalmol

Am J Ophthalmol

Ophthalmic Physiol Opt

Ophthalmic Physiol Opt

Eye changes after forty

Am Fam Physician

Ocular problems of young adults in rural Nigeria

Int Ophthalmol

Prevalence of near vision deficiency and related factorsa population-based study

Cad Saude Publica

Further data on presbyopia in different ethnic groups

Am J Optom Arch Am Acad Optom

Original Article
Population-Based Study of Presbyopia in Rural Tanzania