Tags

Type your tag names separated by a space and hit enter

Prevalence of the different types of age-related cataract in an African population.
Invest Ophthalmol Vis Sci. 2001 Oct; 42(11):2478-82.IO

Abstract

PURPOSE

To describe the prevalence of different types of cataract and their association with visual acuity in a Tanzanian population aged 40 years and older.

METHODS

A prevalence survey for lens opacity, glaucoma, and visual impairment was carried out on all residents age 40 and older of six villages in Kongwa, Tanzania. One examiner graded the lens for presence of nuclear (NSC), posterior subcapsular (PSC), and cortical cataract (CC), using the new WHO Simplified Cataract Grading System. Visual acuity was measured in each eye, both presenting and best corrected, using an illiterate E chart.

RESULTS

The proportion of eligible subjects participating was 90% (3268/3641). The prevalence of cataract was as follows: NSC, 15.6%; CC, 8.8%; and PSC, 1.9%. All types of cataract increased with age, from NSC, 1.7%; CC, 2.4%; and PSC, 0.4% for those aged 40 to 49 years to NSC, 59.2%; CC, 23.5%; and PSC, 5.9% for those aged 70 years and older (P < 0.0001 for all cataract types, chi(2) test for trend). Cataract prevalence was higher among women than men for NSC (P = 0.0001), but not for CC (P = 0.15) or PSC (P = 0.25), after adjusting for age. Prevalence rates of visual impairment (BCVA < 6/12), US blindness (< or = 6/60) and WHO blindness (< 6/120) for this population were 13.3%, 2.1%, and 1.3%, respectively. Older age and each of the major types of pure and mixed cataract were independently associated with worse vision in regression modeling.

CONCLUSIONS

Unlike African-derived populations in Salisbury and Barbados, NSC rather than CC was most prevalent in this African population. The seeming lower prevalence of CC may to some extent be explained by different grading schemes, differential availability of cataract surgery, the younger mean age of the Tanzanian subjects, and a higher prevalence of NSC in this population.

Authors+Show Affiliations

Dana Center for Preventive Ophthalmology, Wilmer Ophthalmological Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA. ncongdon@jhmi.eduNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, P.H.S.

Language

eng

PubMed ID

11581186

Citation

Congdon, N, et al. "Prevalence of the Different Types of Age-related Cataract in an African Population." Investigative Ophthalmology & Visual Science, vol. 42, no. 11, 2001, pp. 2478-82.
Congdon N, West SK, Buhrmann RR, et al. Prevalence of the different types of age-related cataract in an African population. Invest Ophthalmol Vis Sci. 2001;42(11):2478-82.
Congdon, N., West, S. K., Buhrmann, R. R., Kouzis, A., Muñoz, B., & Mkocha, H. (2001). Prevalence of the different types of age-related cataract in an African population. Investigative Ophthalmology & Visual Science, 42(11), 2478-82.
Congdon N, et al. Prevalence of the Different Types of Age-related Cataract in an African Population. Invest Ophthalmol Vis Sci. 2001;42(11):2478-82. PubMed PMID: 11581186.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Prevalence of the different types of age-related cataract in an African population. AU - Congdon,N, AU - West,S K, AU - Buhrmann,R R, AU - Kouzis,A, AU - Muñoz,B, AU - Mkocha,H, PY - 2001/10/3/pubmed PY - 2001/10/19/medline PY - 2001/10/3/entrez SP - 2478 EP - 82 JF - Investigative ophthalmology & visual science JO - Invest. Ophthalmol. Vis. Sci. VL - 42 IS - 11 N2 - PURPOSE: To describe the prevalence of different types of cataract and their association with visual acuity in a Tanzanian population aged 40 years and older. METHODS: A prevalence survey for lens opacity, glaucoma, and visual impairment was carried out on all residents age 40 and older of six villages in Kongwa, Tanzania. One examiner graded the lens for presence of nuclear (NSC), posterior subcapsular (PSC), and cortical cataract (CC), using the new WHO Simplified Cataract Grading System. Visual acuity was measured in each eye, both presenting and best corrected, using an illiterate E chart. RESULTS: The proportion of eligible subjects participating was 90% (3268/3641). The prevalence of cataract was as follows: NSC, 15.6%; CC, 8.8%; and PSC, 1.9%. All types of cataract increased with age, from NSC, 1.7%; CC, 2.4%; and PSC, 0.4% for those aged 40 to 49 years to NSC, 59.2%; CC, 23.5%; and PSC, 5.9% for those aged 70 years and older (P < 0.0001 for all cataract types, chi(2) test for trend). Cataract prevalence was higher among women than men for NSC (P = 0.0001), but not for CC (P = 0.15) or PSC (P = 0.25), after adjusting for age. Prevalence rates of visual impairment (BCVA < 6/12), US blindness (< or = 6/60) and WHO blindness (< 6/120) for this population were 13.3%, 2.1%, and 1.3%, respectively. Older age and each of the major types of pure and mixed cataract were independently associated with worse vision in regression modeling. CONCLUSIONS: Unlike African-derived populations in Salisbury and Barbados, NSC rather than CC was most prevalent in this African population. The seeming lower prevalence of CC may to some extent be explained by different grading schemes, differential availability of cataract surgery, the younger mean age of the Tanzanian subjects, and a higher prevalence of NSC in this population. SN - 0146-0404 UR - https://www.unboundmedicine.com/medline/citation/11581186/Prevalence_of_the_different_types_of_age_related_cataract_in_an_African_population_ L2 - http://iovs.arvojournals.org/article.aspx?volume=42&amp;page=2478 DB - PRIME DP - Unbound Medicine ER -