Use of cataract surgery in urban Beijing: a post screening follow-up of the elderly with visual impairment due to age-related cataract.

OBJECTIVE: To understand the perception for the use of cataract surgical services in a population of acceptors and non-acceptors of cataract surgery in urban Beijing. METHODS: From a community-based screening program a total of 158 patients with presenting visual acuity of less than 6/18 on either eye due to age-related cataract were informed about the possibility of surgical treatment. These patients were interviewed and re-examined 36 to 46 months after initial screening. The main reasons for not accepting surgery were obtained using a questionnaire. Vision function and vision-related quality of life scores were assessed in those who received and did not receive surgery. RESULTS: At the follow-up examination 116 of the 158 patients were available and 36 (31.0%) had undergone cataract surgery. Cases who chose surgery had higher education level than those who did not seek surgery (OR=2.64, 95% CI: 1.08-6.63, P=0.02). There were no significant differences in vision function (P=0.11) or quality of life scores (P=0.16) between the surgery group and the non-surgery group. Main reasons for not having surgery included no perceived need (50.0%), feeling of being "too old" (19.2%), and worry about the quality of surgery (9.6%). Cost was cited by 1 (1.9%) subject as the main reason for not seeking surgery. CONCLUSIONS: The data suggest that in China's capital urban center for patients with moderate visual impairment there is a relative low acceptance rate of cataract surgery, mainly due to people's perception of marginal benefits of surgery. Cost is not a determining factor as barrier to undergo surgery and patients with poorer education are less likely to undertake surgery.

[Evaluation on the noninvasive measurement of macular pigment optical density by a novel technique].

OBJECTIVE: To evaluate the measurement of macular pigment optical density (MPOD) by a novel instrument MPS1000 as compared to that measured by the traditional heterochromatic flicker photometer (HFP). METHODS: Method-comparative study. MPOD at 0.5° eccentricity was measured simultaneously by the two different instruments in 111 eyes of the 59 healthy subjects. Test-retest variability was evaluated for each instrument over a 1-week period in 8 subjects. RESULT: The mean MPOD levels measured by the MPS1000 and HFP were 0.40±0.18 and 0.47±0.15, respectively, which were statistically significantly different by the paired t-test (t=3.95, P<0.001). A positive linear correlation was observed for MPOD at 0.5° eccentricity between the two different instruments (r=0.4, P<0.001). The 95% limit of agreement was 0.07±0.35 as shown by Bland-Altman analysis. Intersessional repeatability, expressed as a coefficient of repeatability, was 0.26 for HFP and 0.18 for MPS1000. CONCLUSION: MPOD levels measured by MPS1000 were significantly higher as compared to that measured by the traditional HFP, suggesting that it is inappropriate to directly compare the MPOD levels measured by these two methodologies.

Candidate gene association study for diabetic retinopathy in Chinese patients with type 2 diabetes.

PURPOSE: To investigate whether variants in a set of eight candidate genes are associated with diabetic retinopathy (DR) in a cohort of Chinese patients with type 2 diabetes mellitus (T2DM). METHODS: Case-control study. Patients with T2DM were recruited from the Desheng community in urban Beijing and assigned into a DR group or diabetic without retinopathy (DWR) group, based on the duration of diabetes and grading of fundus images. Twenty-six single-nucleotide polymorphisms (SNPs) within eight candidate genes, including PPARγ, vascular endothelial growth factor (VEGF) and its receptor kinase insert domain receptor (KDR), erythropoietin, aldose reductase, protein kinase C-ß, angiotensin-converting enzyme, and intercellular adhesion molecule 1, were analyzed using the MassARRAY genotyping system. RESULTS: A total of 500 patients with T2DM (216 with DR and 284 with DWR) were enrolled in the study. Significant associations of DR were noted with genotypes of four SNPs-rs699947 (p<0.001), rs833061 (p = 0.001), rs13207351 (p<0.001), and rs2146323 (p=0.006)--in the VEGF gene and one variant, rs2071559, in the KDR gene (p=0.034). After adjustment for covariates, significant association of DR remained with the homozygous genotype of the minor allele for the SNPs rs699947 (odds ratio [OR] = 3.54, 95% confidence interval [CI]: 1.12-11.19), rs833061 (OR = 3.72, 95% CI: 1.17-11.85), rs13207351 (OR = 3.76, 95% CI: 1.21-11.71), and rs2146323 (OR = 2.8, 95% CI: 1.46-5.37) in the VEGF gene as well as the SNP rs2071559 (OR = 1.62, 95% CI: 1.08-2.41) in the KDR gene. However, only rs699947 and rs13207351 in the VEGF gene remained statistically significant after Bonferroni correction. No associations were found in other genes tested. CONCLUSIONS: These data expanded previous observations on the association of DR with variants in the VEGF gene in Chinese patients with T2DM. Moreover, a possible association between DR and KDR polymorphisms is suggested.

[A survey of vision-related quality of life in patients with exudative age-related macular degeneration].

OBJECTIVE: To evaluate the vision-related quality of life in patients with exudative age-related macular degeneration (AMD). METHODS: Retrospective case-series study.One hundred and twenty-two patients with exudative AMD who were treated in Beijing Tongren Eye Center from July 2007 to July 2008 were invited to participate in this study.Vision-related quality of life was evaluated by the 25-item National Eye Institute Visual Functioning Questionnaire.Statistical analysis was performed using t test for data which were normal distribution and using Wilcoxon rank sum test for data which were abnormal distribution. RESULTS: Eighty-seven cases were fully completed and included in the final analysis within the 122 questionnaires. The total score of the questionnaire was 57.2 ± 18.4, excluded driving item. The lowest scoring item was near activities with mean score of 30.8 ± 22.3. There was statistically significant difference in mental health between male (52.9 ± 26.3) and female (40.8 ± 26.0) (w = 1 175, P < 0.05). Except for the general health and ocular pain, patients with binocular involvement showed statistically significant lower scores than those with monocular involvement in all other subscales (P < 0.05). The two age groups (patients <65 vs. ≥ 65 years old) in binocular involvement group showed statistically significant difference only in the subscale of social activities (56.6 ± 22.2 vs.42.3 ± 30.2) (w = 97, P = 0.013). CONCLUSIONS: This study suggests that exudative AMD damaged patients'near activities seriously.Female patients tends to have lower scores than male in mental health. The score of patients with binocular involvement is lower than that of patients with monocular involvement. Age has significant effects on the social activities of those patients with binocular involvement.

[Diabetes self-management and its association with diabetic retinopathy in patients with type 2 diabetes].

OBJECTIVE: To investigate the association of diabetic self-management with the risk of diabetic retinopathy (DR) in patients with type 2 diabetes mellitus. METHODS: Cross-sectional study. Recruited patients with type 2 diabetes mellitus in the Desheng community of urban Beijing between November 2009 and May 2011. All patients were surveyed using a standardized questionnaire and underwent detailed ophthalmic examination. Patients were classified into DR group or diabetic without retinopathy (DWR) group according to the grading of fundus color photographs using the Early Treatment of Diabetic Retinopathy Study (ETDRS) standard grading protocol. In the DR group, proliferative diabetic retinopathy (PDR) was further defined. The overall levels of diabetes self-management in the study population were assessed and compared for the differences between DR and DWR, PDR and NPDR groups. RESULTS: One thousand one hundred patients with type 2 diabetes mellitus were recruited. The prevalence of DR was 32.1% (353/1100) in the study population. Sixty-three percent (652/1035) of patients had glycated hemoglobin (HbA1c) level less than 7.0%. The majority of patients (85.4%, 916/1072) conducted a diet control, 77.3% (827/1070) exercised, 56.0% (609/1088) monitored blood glucose regularly, 56.8% (416/733) detected HbA1c more than once every six months, 71.7% (762/1062) had ophthalmologic examination after the diagnosis of diabetes mellitus, and 47.9% (525/1097) had mydriatic check-up. Increased risk of DR was associated with longer duration of diabetes (more than 10 years) (OR = 3.90, 95% CI:2.97-5.51, P < 0.05), higher HbA1c level of ≥ 7.0% (OR = 3.23, 95% CI:2.44-4.28, P < 0.05), insulin therapy (OR = 4.82, 95% CI:3.55-6.57, P < 0.05), male gender (OR = 1.41, 95% CI:1.08-1.84, P < 0.05), lower level of education (OR = 1.90, 95% CI:1.39-2.62, P < 0.05), lower monthly income (OR = 1.46, 95% CI:1.12-1.91, P < 0.05), lower obedience to diet control (OR = 1.72, 95% CI:1.22-2.43, P < 0.05), no exercise (OR = 1.42, 95% CI:1.04-1.94, P < 0.05), change of therapeutic protocol during the last five years (OR = 1.78, 95% CI:1.32-2.41, P < 0.05), and family history of diabetes (OR = 1.35, 95% CI:1.01-1.78, P < 0.05). Increased risk of PDR was associated with the diagnosis age of diabetes (OR = 0.92, 95% CI:0.89-0.95, P < 0.05), longer duration of diabetes (more than 10 years) (OR = 4.54, 95% CI:1.95-12.32, P < 0.05), and insulin therapy (OR = 4.85, 95% CI:2.34-10.90, P < 0.05). In the multifactor logistic regression model, male gender (OR = 2.21, 95% CI:1.57-3.11, P < 0.05), lower level of education (OR = 1.98, 95% CI:1.33-2.94, P < 0.05), lower monthly income (OR = 1.66, 95% CI:1.15-2.39, P < 0.05) ,longer duration of diabetes (more than 10 years) (OR = 2.46, 95% CI:1.77-3.41, P < 0.05) ,HbA1c ≥ 7.0% (OR = 2.24, 95% CI:1.64-3.07, P < 0.05) and insulin therapy (OR = 3.38, 95% CI:2.38-4.8, P < 0.05) were associated with higher risk of DR. The diagnosis age of diabetes (OR = 0.94, 95% CI:0.91-0.98, P < 0.05) and insulin therapy (OR = 3.49, 95% CI:1.47-8.27, P < 0.05) were associated with PDR. CONCLUSION: Higher risk of DR is associated with longer duration of diabetes,insulin therapy, higher HbA1c level, male gender, and lower level of education, whereas higher risk of DR is also associated with lower obedience to diet control and less exercise, which suggest that lower level of diabetic self-management increased the risk of DR.

Comparison between ophthalmologists and community health workers in screening of shallow anterior chamber with oblique flashlight test.

OBJECTIVE: To study the agreement between ophthalmologists and community health workers in detecting shallow anterior chamber with oblique flashlight test. METHODS: Totally 425 subjects were given an eye examination in a community health center. The anterior chamber depth of each subject was examined by one ophthalmologist and two trained community health workers (one nurse and one non-professional health worker) using oblique flashlight test. Inter-observer agreement was determined using the weighted kappa statistic. RESULTS: Among the enrolled subjects, 148 (35%) were male and 277 (65%) were female. Good agreement was noted in all the three observers. The comparison between the ophthalmologist and the nurse showed a kappa statistic of 0.42 for both eyes (P < 0.001). The kappa statistic was 0.54 and 0.52 for right and left eyes respectively between the ophthalmologist and the non-professional health worker (P<0.001). As for agreement between the nurse and the non-professional health, worker, the kappa statistic was 0.49 and 0.38 for right and left eyes, respectively (P < 0.001). CONCLUSION: The oblique flashlight test may be used as an applicable tool by trained community health workers for screening of shallow anterior chamber and play a role in blindness prevention in community.

The diurnal variation pattern of choroidal thickness in macular region of young healthy female individuals using spectral domain optical coherence tomography.

AIM: To investigate the pattern of diurnal variations of choroidal thickness of macular region of healthyindividuals. METHODS: A prospective study of 32 healthy female subjects was conducted. Each subject underwent 1) a questionnaire on daily schedule, 2) the Pittsburgh Sleep Quality Index questionnaire (PSQI), and 3) ocular examinations including an eye dominance test, fundus photography, and sequential optical coherence tomography (OCT) imaging, on two separate days at five fixed 3h time intervals. Choroidal thickness was measured by two masked graders. RESULTS: A significant diurnal variation of choriodal thickness at fovea (P<0.001), at 500 µm nasal (P<0.001), temporal to fovea (P=0.01) or 1500 µm nasal to fovea (P=0.001) was observed. The median choroidal thickness peaked at 11:00 at fovea (P=0.01), at 500 µm nasal (P=0.009) and temporal (P=0.03) to fovea. The median amplitude of foveal choroidal thickness was 20.5 µm (13, 31) and 20.0 µm (12.5, 28.2) for the first and second series of measurements, respectively. The greater amplitude of foveal choroidal thickness was associated with thickner initial foveal choroidal thickness [0.05 (0.03, 0.08), P=0.01], dominant eye [10.51 (4.02, 14.60), P=0.04] in the multivariate linear regression. CONCLUSION: Our data show a significant diurnal variation of the choroidal thickness at fovea, at 500 µm nasal and temporal to fovea and 1500 µm nasal to fovea. Thicker initial foveal choroidal thickness and being dominant eye may influence the amplitude of foveal choroidal thickness.

Association of macular pigment optical density with early stage of non-proliferative diabetic retinopathy in Chinese patients with type 2 diabetes mellitus.

AIM: To detect the association between macular pigment optical density (MPOD), which reflects the antioxidant ability of retina, and diabetic retinopathy (DR) and to investigate the correlated factors of MPOD. METHODS: Totally 435 subjects of urban Chinese were recruited to the study and divided into 3 groups: non-diabetes mellitus controls (NDM), diabetic patients without retinopathy (DWR), and patients with early stage of non-proliferative diabetic retinopathy (DR). Demographic and lifestyle characteristics were ascertained by questionnaire. A food-frequency questionnaire, general physical and ophthalmic examinations were completed for all participants. MPOD was measured by heterochromatic flicker photometry. Foveal thickness was measured by optical coherence tomography. The difference of MPOD among 3 groups was analyzed by analysis of covariance. The correlation analyses of MPOD with the candidate influence factors were assessed using the generalized estimating equations (GEE) model. RESULTS: Of the 435 participants, 34 could not perform the MPOD measurements. Final analysis included 401 subjects, including 48 were in DR group, 134 in DWR group, and 219 in NDM group. MPOD was not significantly different among DR (0.49±0.21), DWR (0.45±0.21), and NDM (0.49±0.17) groups (P=0.24) after adjustment for fasting plasma glycemia, central foveal thickness, green vegetables, Chinese wolfberry, carotene and vitamin E. For all the 401 participants included, MPOD was positively associated with central foveal thickness (E=0.0007, P=0.001), Chinese wolfberry (E=0.0345, P=0.01), and green vegetables (E=0.0596, P<0.001) intake. CONCLUSION: The data suggest that MPOD level is not statistically significantly influenced by the onset of diabetes or early stage of DR in the studied population. MPOD level is positively associated with thicker central foveal thickness and higher intake of foods containing carotenoids.

Relationship of retinal vascular calibre and diabetic retinopathy in Chinese patients with type 2 diabetes mellitus: the Desheng Diabetic Eye Study.

AIMS: To describe the relationship of retinal arteriolar and venular calibre with diabetic retinopathy (DR) and related risk factors, including glucose levels and other biomarkers in a Chinese population with type 2 diabetes mellitus (T2DM). METHODS: A cross-sectional study. Patients with T2DM were recruited from a local community in urban Beijing. Seven fields 30° colour fundus photographs were taken and examined for the presence and severity of DR using a standardised grading system. Retinal vascular calibres were measured and expressed as average central retinal arteriolar and venular equivalent using a computer-based program. RESULTS: A total of 1340 patients with T2DM were included for analysis. Of these, 472 (35.22%) had DR. Wider retinal venular calibre, but not arteriolar calibre, was associated with increasing glucose and glycosylated haemoglobin A1c levels (p<0.006) and dyslipidaemia (p for trend <0.05). After adjusting for possible covariates, the higher quartile of retinal venular calibre was associated with higher prevalence of any DR (OR 2, 95% CI 1.36 to 2.95). Venular calibre increased from 224.33 µm in those without retinopathy to 231.21 µm in those with mild, 241.01 µm in those with moderate and 235.65 µm in those with severe retinopathy (p for trend <0.001). Arteriolar calibre was not associated with DR. CONCLUSIONS: In the current study, wider venular calibre, but not arteriolar calibre, was shown to be associated with development and increased severity of DR independently from other risk factors in a Chinese diabetic population.

Measurement of macular pigment optical density among healthy Chinese people and patients with early-stage age-related macular degeneration.

AIM: To measure the macular pigment optical density (MPOD) in healthy Chinese people and patients with early age-related macular degeneration (AMD). METHODS: Cross-sectional population based study. Demographic and lifestyle characteristics were ascertained by questionnaire. A food frequency questionnaire was completed for all participants. Participants underwent general physical and ophthalmic examinations and MPOD was measured by heterochromatic flicker photometry. Foveal architecture was measured by optical coherence tomography. RESULTS: MPOD of 225 participants (122 healthy and 103 early AMD) was 0.48±0.18. Patients with early AMD (0.52±0.19) tended to have higher MPOD levels than healthy people (0.47±0.17), but the difference was not statistically significant (P=0.06). Participants with carrot or corn oil intake every week tended to have higher levels of MPOD (P=0.002 and 0.008 respectively) while those with corn intake had relatively lower level of MPOD (P=0.01). MPOD increased with the center foveal thickness (P=0.01). CONCLUSION: Our findings show that there is no statistically significant association between MPOD and early AMD in the studied population. MPOD is related to center foveal thickness and diets would influence MPOD levels.

Strategies of digital fundus photography for screening diabetic retinopathy in a diabetic population in urban China.

PURPOSE: To evaluate the effect of mydriasis and different field strategies on technical failure, probability to refer diabetic retinopathy (DR, sensitivity) and probability not to refer patients without DR (specificity) of digital photography in screening with a fundus camera. METHODS: A total of 531 patients with diabetes underwent fundus photography with cross-combinations of mydriasis/nonmydriasis and single-field/two-field strategies, followed by slit lamp biomicroscopic examination by a trained ophthalmologist. Fundus photographs were graded independently by another experienced ophthalmologist. Calculations were first based on cases with non-gradable images treated as being referred and then with them excluded. RESULTS: Percentages of DR and referable DR in this patient cohort were 22.4% and 7.7%, respectively, based on slit lamp biomicroscopic examination. Mydriasis significantly reduced the technical failure rate from 27.1% to 8.3% under a single-field strategy, and from 28.2% to 8.9% under a two-field strategy. As compared to the single-field strategy, the two-field strategy increased sensitivity from 75.6% to 87.8% without mydriasis and from 73.2% to 90.2% with mydriasis. Mydriasis increased specificity from 68.8% to 84.3% in the single-field strategy and from 64.7% to 81.6% in the two-field strategy. Had the subjects with non-gradable images been excluded, the two-field strategy without mydriasis reported sensitivity of 85.7% and specificity of 91.6%. CONCLUSIONS: Both mydriasis and the two-field strategy are useful in photographic screening tests. Technical failure should be taken into consideration when screening strategies for DR are determined.