TY - JOUR
T1 - Age, sex, and cohort effects in a longitudinal study of trachomatous scarring
AU - Wolle, Meraf
AU - Munoz, Beatriz
AU - Mkocha, Harran
AU - West, Sheila K.
PY - 2009/2
Y1 - 2009/2
N2 - PURPOSE. To determine the 5-year incidence rate of scarring, and associated factors, in the population of Maindi, Tanzania. METHODS. A census of every resident was obtained at baseline, and ocular examinations for the presence and severity of trachoma were performed. Images of the upper eyelid were taken and graded for the presence and severity of scarring, according to a four-step severity scale based on photographs. Five years after baseline, a second series of images was taken and graded for scarring. Incident scarring was defined as new scars in those without scarring at baseline; progression was defined as those with scars that worsened by one step or more at 5 years. RESULTS. The rate of scarring at baseline increased with age, from 1% in the <6-year to 38% in the 41+-year age group. Females at any age had more scarring than did males. The 5-year incidence rate of scarring was 0.20 (95% confidence interval [CI], 0.16-0.25), but varied with age up to 0.43 in the 41+-year group. There was a striking cohort effect, with those aged less than 16 years at baseline having more prevalent scarring and incidence rates comparable to those aged 16 to 40. Progression rates averaged 0.47 (95% CI, 0.36-0.58). CONCLUSIONS. In this trachoma-endemic community, incident scarring was high, especially in the younger cohorts. A dramatic increase in risk of trachomatous scarring occurred approximately 15 years ago and appears to be unabated. Trachoma control programs to reduce risk of scarring are urgently needed to avoid blinding complications in this community.
AB - PURPOSE. To determine the 5-year incidence rate of scarring, and associated factors, in the population of Maindi, Tanzania. METHODS. A census of every resident was obtained at baseline, and ocular examinations for the presence and severity of trachoma were performed. Images of the upper eyelid were taken and graded for the presence and severity of scarring, according to a four-step severity scale based on photographs. Five years after baseline, a second series of images was taken and graded for scarring. Incident scarring was defined as new scars in those without scarring at baseline; progression was defined as those with scars that worsened by one step or more at 5 years. RESULTS. The rate of scarring at baseline increased with age, from 1% in the <6-year to 38% in the 41+-year age group. Females at any age had more scarring than did males. The 5-year incidence rate of scarring was 0.20 (95% confidence interval [CI], 0.16-0.25), but varied with age up to 0.43 in the 41+-year group. There was a striking cohort effect, with those aged less than 16 years at baseline having more prevalent scarring and incidence rates comparable to those aged 16 to 40. Progression rates averaged 0.47 (95% CI, 0.36-0.58). CONCLUSIONS. In this trachoma-endemic community, incident scarring was high, especially in the younger cohorts. A dramatic increase in risk of trachomatous scarring occurred approximately 15 years ago and appears to be unabated. Trachoma control programs to reduce risk of scarring are urgently needed to avoid blinding complications in this community.
UR - http://www.scopus.com/inward/record.url?scp=59449097039&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=59449097039&partnerID=8YFLogxK
U2 - 10.1167/iovs.08-2414
DO - 10.1167/iovs.08-2414
M3 - Article
C2 - 18936137
AN - SCOPUS:59449097039
SN - 0146-0404
VL - 50
SP - 592
EP - 596
JO - Investigative Ophthalmology and Visual Science
JF - Investigative Ophthalmology and Visual Science
IS - 2
ER -