Early Age-Related Macular Degen-eration is common in people of African descent, say researchers in the Barbados Eye Studies (BESs). However, the nine-year data on natural history study also found late AMD is infrequent. These long-term observations, the researchers say, provide further evidence for the lower AMD risk in black populations compared with white populations for a condition that will affect almost 3 million people in the United States by 2020, according to estimates the study quotes.

The study included 2,793 participants (81 percent of eligible) after nine years' follow-up. According to this population-based cohort study to provide nine-year incidence estimates of AMD-related features based on fundus photographic gradings and/or clinical examinations, the overall incidence rate of early AMD was 12.6 percent (95 percent confidence interval [CI], 11.0-14.1 percent), and that of late AMD was 0.7 percent (95 percent CI, 0.4 percent-1.1 percent). The study found that both increased with age (p<0.05).

For early AMD, incidence ranged from 10.7 percent at 40 to 49 years of age to 16.8 percent at >70 years. For late AMD, incidence increased from 0.1 to 2.3 percent in the same age groups. Late AMD was more likely to develop in eyes with pigment changes (risk ratio, 5.8; 95 percent CI, 2.0-16.8) and retinal epithelial atrophy (RR, 5.4; 95 percent CI, 1.9-15.8) at baseline. Crude RRs indicated significant associations of late AMD to elevated systolic blood pressure and diabetes history, but only the diabetes relationship was suggested after adjusting for age, with borderline statistical significance (age-adjusted RR, 2.7; p=0.054).
(Ophthalmology 2006;113:29-35)
Leske MC, Wu S, Hennis A, Nemesure B, Yang L, Hyman L, Schachat AP.


Latanoprost and Timolol vs. the Individual Components

The fixed combination of latanoprost and timolol administered once daily passed a non-inferiority test compared to the unfixed combination of latanoprost once daily and timolol twice daily, say researchers for a Euro-pean-Canadian study. The fixed combination provides an effective and well-tolerated alternative to multiple instillations, the 12-week, randomized, double-masked, study found.

Patients received either the fixed combination of latanoprost and timolol once daily in the evening and a placebo in the morning and evening, or the unfixed combination of lat-anoprost once daily in the evening and timolol in the morning and evening.

The study included 517 randomized pa-tients (with ocular hypertension; open-angle, pigmentary, or exfoliation glaucoma; and baseline [after washout] intraocular pressure levels between 23 and 33 mmHg) and was conducted at 53 centers throughout Europe and Canada; visits were at weeks two, six and 12. The 502 patients were included in intent-to-treat analyses (fixed combination, n=255; unfixed combination, n=247). For the fixed- and unfixed-combination groups, mean baseline diurnal IOP levels were 25.4 mmHg, and 25.2 mmHg, respectively, and mean diurnal IOP reductions were 8.7 mmHg and 9 mmHg (between-treatment difference, 0.3 mmHg; 95 percent CI, -0.1 to 0.7 mmHg; p=0.15). Both treatments were well-tolerated, but the fixed combination demonstrated a better tolerability profile with regard to percentages of patients reporting at least one adverse event and reporting an ocular adverse event.

The results of the study show a fixed combination provides a once-daily alternative to the three instillations needed with the individual components, which may interfere with patient compliance.
(Ophthalmology 2006;113:70-76)
Diestelhorst M, Larsson L.

 

OCT, RTA Results Similar in Diabetics

Optical coherence tomography and the retinal thickness analyzer measuring techniques yielded similar results when examining eyes of patients with diabetes, although absolute values differed, according to a study by German researchers. OCT seems  more suitable in the clinical screening for macular edema due to its high sensitivity (>90 percent) with appropriate analysis parameters. The RTA is more prone to erroneous or missing thickness readings particularly under difficult measuring conditions.

OCT and the RTA were compared for the same study population of diabetic patients, and the findings were related to macular edema shown by stereo fundus photography (SFP). The maculas of 124 eyes from 69 pa-tients with diabetes mellitus were examined with OCT and the RTA. Measurements of retinal thickness were compared with signs of macular edema shown by SFP. For each eye, nine different sectors were analyzed (a foveal sector, four parafoveal sectors, and four extrafoveal sectors). Thirteen eyes with a normal macula served as controls. Sensitivity and specificity of detecting clinically significant macular edema were calculated.

Of 111 eyes, 64 showed signs of CSME by SFP. Mean retinal thick-ness ± SD of the foveal sector was 249 ±104 µm by the RTA and 295 ±124 µm by OCT measurements. There was a moderate overall correlation between OCT and the RTA (r=0.66). The correlation was best in the foveal sector (r=0.82). Overall, correlation with SFP was better for OCT (r=0.77) than for the RTA (r=0.62). Sen-sitivity of detecting CSME was consistently high-er with OCT, while the RTA showed higher specificity.
(Retina 2006;26:49-57)
Goebel W, Franke R.

 

Preop Refractive Status Impacts Postop Hopes of Patients

Cataract patients' preopera-tive refractive correction appears to play a significant role in their postoperative expectations, say researchers in the UK. Those who wear glasses prior to cataract surgery may expect to wear them afterwards, but those who don't may not.

From October 2003 to February 2004, 189 first-eye cataract surgery patients at three centers in the UK completed a questionnaire that assessed refractive expectations. [Mean patient age was 74 years, with a range of 41 to 97 years, with 64 percent of respondents being women.] The study questionnaire inquired into patients' expectations on vision after surgery and to what areas the patient might need spectacles for postop, such as for reading and driving.

The study found patients who did not wear glasses prior to surgery did not expect to need them after the procedure, puting them at risk for "refractive disappointment and complaint," according to the study. Not surprisingly, patients generally consider the opportunity to be free of glasses as very important.

On the 10-point Likert scale, with zero being the lowest, and 10 the highest, median patient scores for the perceived likelihood of needing spectacles after surgery were eight for both distance and near correction. Median score of the importance of not needing spectacles was eight for both distance and near.
(J Cataract Refract Surg 2005; 31:1970-1975)
Hawker MJ, Madge SN, Baddeley PA, Perry SR.