Trans-Lamina Cribrosa Pressure Difference and Open-Angle Glaucoma. The Central India Eye and Medical Study

Purpose

To assess associations of the trans-lamina cribrosa pressure difference (TLCPD) with glaucomatous optic neuropathy.

Methods

The population-based Central India Eye and Medical Study included 4711 subjects. Based on a previous study with lumbar cerebrospinal fluid pressure (CSFP) measurements, CSFP was calculated as CSFP[mmHg] = 0.44 Body Mass Index[kg/m2]+0.16 Diastolic Blood Pressure[mmHg]−0.18×Age[Years] −1.91. TLCPD was IOP–CSFP.

Results

Mean TLCPD was 3.64±4.25 mm Hg in the non-glaucomatous population and 9.65±8.17 mmHg in the glaucomatous group. In multivariate analysis, TLCPD was associated with older age (P<0.001; standardized coefficient beta:0.53; regression coefficient B:0.18; 95% confidence interval (CI):0.17, 0.18), lower body mass index (P<0.001; beta: −0.28; B: −0.36; 95%CI: −0.38, −0.31), lower diastolic blood pressure (P<0.001; beta: −0.31; B: −0.12; 95%CI: −0.13, −0.11), higher pulse (P<0.001; beta:0.05; B:0.02; 95%CI:0.01,0.2), lower body height (P = 0.02; beta: −0.02; B: −0.01; 95%CI: −0.02,0.00), higher educational level (P<0.001; beta:0.04; B:0.15; 95%CI:0.09,0.22), higher cholesterol blood concentrations (P<0.001; beta:0.04; B:0.01; 95%CI:0.01,0.01), longer axial length (P = 0.006; beta:0.03; B:0.14; 95%CI:0.04,0.24), thicker central cornea (P<0.001; beta:0.15; B:0.02; 95%CI:0.02,0.02), higher corneal refractive power (P<0.001; beta:0.07; B:0.18; 95%CI:0.13,0.23) and presence of glaucomatous optic neuropathy (P<0.001; beta:0.11; B:3.43; 95%CI:2.96,3.99). Differences between glaucomatous subjects and non-glaucomatous subjects in CSFP were more pronounced for open-angle glaucoma (OAG) than for angle-closure glaucoma (ACG) (3.0 mmHg versus 1.8 mmHg), while differences between glaucomatous subjects and non-glaucomatous subjects in IOP were higher for ACG than for OAG (8.5 mmHg versus 3.0 mmHg). Presence of OAG was significantly associated with TLCPD (P<0.001; OR:1.24; 95%CI:1.19,1.29) but not with IOP (P = 0.08; OR:0.96; 95%CI:0.91,1.00). Prevalence of ACG was significantly associated with IOP (P = 0.04; OR:1.19; 95%CI:1.01,1.40) but not with TLCPD (P = 0.92).

Conclusions

In OAG, but not in ACG, calculated TLCPD versus IOP showed a better association with glaucoma presence and amount of glaucomatous optic neuropathy. It supports the notion of a potential role of low CSFP in the pathogenesis of open-angle glaucoma.     

Intraocular Pressure and Associations in Children. The Gobi Desert Children Eye Study

Purpose

To assess the intraocular pressure (IOP) and its association in children in a population living in an oasis in the Gobi Desert.

Methods

The cross-sectional school-based study included all schools in the Ejina region. The children underwent an ophthalmic examination, non-contact tonometry and measurement of blood pressure and body height and weight.

Results

Out of eligible 1911 children, 1565 (81.9%) children with a mean age of 11.9±3.5 years (range: 6–21 years) participated. Mean spherical refractive error was −1.58±2.00 diopters. In multivariate analysis, higher IOP (right eye) was associated with younger age (P<0.001; standardized coefficient beta: −0.13; regression coefficient B: −0.13; 95% Confidence interval (CI):−0.18, −0.07), higher diastolic blood pressure (P<0.001;beta:0.13;B:0.05;95%CI:0.03,0.07), higher corneal refractive power (P<0.001;beta:0.11;B:0.23;95%CI:0.12,0.34), more myopic refractive error (P = 0.035;beta: −0.06;B: −0.10;95%CI: −0.19, −0.001), and Han Chinese ethnicity of the father (P = 0.03;beta:0.06;B:0.42;95%CI:0.04,0.89). If age and diastolic blood pressure were dropped, higher IOP was associated with higher estimated cerebrospinal fluid pressure (CSFP) (P<0.001;beta:0.09; B:0.13;95%CI:0.06,0.21) after adjusting for higher corneal refractive power (P<0.001) and Han Chinese ethnicity of the father (P = 0.04). Correspondingly, higher IOP of the left eye was associated with younger age (P<0.001;beta: −0.15;B: −0.16;95%CI: −0.21, −0.10), female gender (P<0.001;beta:0.09;B:0.65;95%CI:0.30,1.01), higher corneal refractive power (P<0.001;beta:0.08;B:0.19;95%CI:0.06,0.32), more myopic refractive error (P = 0.03;beta: −0.06;B: −0.12;95%CI: −0.22, −0.01), and higher estimated CSFP (P<0.001;beta:0.11;B:0.17;95%CI:0.09,0.24).

Conclusions

In school children, higher IOP was associated with steeper corneal curvature and with younger age and higher blood pressure, or alternatively, with higher estimated CSFP. Corneal curvature radius should be included in the correction of IOP measurements. The potential association between IOP and CSFP as also assumed in adults may warrant further research.     

Ophthalmoscopic Assessment of the Retinal Nerve Fiber Layer. The Beijing Eye Study

Purpose

To examine the retinal nerve fiber layer (RNFL) ophthalmoscopically, to search for localized RNFL defects, and to assess factors associated with RNFL visibility in a population-based setting.

Methods

The population-based cross-sectional Beijing Eye Study 2006 included 3251 subjects. Using color fundus photographs, RNFL visibility was assessed in grades from 0 to 8 in 8 fundus sectors. Localized RNFL defects were defined as wedge-shaped defects running towards the optic disc.

Results

After exclusion of subjects with optic media opacities, 2602 subjects (mean age:58.1±9.0 years) were included. RNFL visibility score was highest (P<0.001) in the temporal inferior region, followed by the temporal superior region, nasal superior region, and nasal inferior region. In multivariate analysis, higher RNFL visibility score was associated with younger age (P<0.001;standardized coefficient beta:−0.44;regression coefficient B: −0.22; 95%CI: −0.24, −0.20), female gender (P<0.001;beta:0.11;B:1.00;95%CI:0.67,1.32), higher blood concentration of low-density lipoproteins (P = 0.002;beta:0.07;B:0.34;95%CI:0.13,0.56), absence of dyslipidemia (P = 0.001;beta: −0.07;B: −0.58;95%CI: −0.93, −0.24), lower blood glucose concentration (P = 0.006;beta: −0.05;B: −0.14;95%CI: −0.24, −0.04), hyperopic refractive error (P<0.001;beta:0.15;B:0.45;95%CI:0.34,0.56), smaller optic disc size (P<0.001;beta: −0.08; B:−0.72;95% CI:−1.04, −0.40), absence of glaucomatous optic neuropathy (P<0.001;beta: −0.06;B: −2.69;95%CI:–4.18, −1.21) and absence of non-glaucomatous optic nerve damage (P = 0.001;beta: −0.06;B: −4.80;95%CI:0. −7.64, −1.96). Localized RNFL defects were detected in 96 subjects (prevalence:3.7±0.45% (95% confidence interval(CI):3.0,4.4). In multivariate analysis, prevalence of localized RNFL defects was associated with higher blood pressure (P<0.001; odds ratio (OR):1.07;95%CI:1.03,1.10), higher concentration of low-density lipoproteins (P = 0.01;OR:1.42;95%CI:1.08,1.85), higher prevalence of glaucomatous optic neuropathy (P<0.001;OR:46.8;95%CI:19.4,113) and diabetic retinopathy (P = 0.002;OR:3.20;95%CI:1.53,6.67), and lower total RNFL visibility (P<0.001;OR:0.92;95%CI:0.88,0.96).

Conclusions

In Chinese aged 45+ years, a decreased RNFL visibility was associated with older age, male gender, dyslipidemia, hyperglycemia, myopia, larger optic disc, and glaucomatous or non-glaucomatous optic neuropathy. Localized RNFL defects (prevalence:3.7±0.45%) were correlated mainly with higher blood pressure, higher concentration of low-density lipoproteins, glaucomatous optic neuropathy and diabetic retinopathy. These data are helpful for the routine ophthalmoscopic examination of the RNFL.     

Intraocular Pressure and Estimated Cerebrospinal Fluid Pressure. The Beijing Eye Study 2011

Purpose

To examine a potential association between intraocular pressure (IOP) and cerebrospinal fluid pressure (CSFP) in a population-based setting.

Methods

The population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6±9.8 years (range: 50–93 years). A detailed ophthalmic examination was performed. Based on a previous study with lumbar cerebrospinal fluid pressure (CSFP) measurements, CSFP was calculated as CSFP [mm Hg] = 0.44×Body Mass Index [kg/m²]+0.16×Diastolic Blood Pressure [mm Hg]–0.18×Age [Years].

Results

In multivariate analysis, IOP was associated with higher estimated CSFP (P<0.001; standardized correlation coefficient beta: 0.27; regression coefficient B: 0.20; 95% confidence interval (CI): 0.16, 0.24), after adjusting for thinner central corneal thickness (P<0.001; beta: 0.45; B: 0.04;95%CI: 0.04,0.04), smaller corneal curvature radius (P<0.001; beta:−0.11; B:−1.13;95%CI:−1.61,−0.64), shallower anterior chamber depth (P = 0.01; beta:−0.05; B:−0.33;95%CI:−0.59,−0.08) and longer axial length (P = 0.002; beta: 0.08; B: 0.20;95%CI: 0.08,0.32)), and after adjusting for the systemic parameters of higher pulse rate (P<0.001; beta: 0.08; B: 0.02;95%CI: 0.01,0.03), higher prevalence of arterial hypertension (P = 0.002; beta: 0.06; B: 0.32;95%CI: 0.12,0.53)), frequency of drinking alcohol (P = 0.02; beta: 0.04; B: 0.09;95%CI: 0.01,0.17), higher blood concentration of triglycerides (P = 0.001; beta: 0.06; B: 0.06;95%CI: 0.02,0.10) and cholesterol (P = 0.049; beta: 0.04; B: 0.08;95%CI: 0.00,0.17), and body mass index (P<0.001; beta:−0.13; B:−0.09;95%CI:−0.13,−0.06). In a parallel manner, estimated CSFP (mean: 10.8±3.7 mm Hg) was significantly associated with higher IOP (P<0.001; beta: 0.13; B: 0.18;95%CI: 0.13,0.23) after adjusting for rural region of habitation (P<0.001; beta:−0.37; B:−2.78;95%CI:−3.07,−2.48), higher systolic blood pressure (P<0.001; beta: 0.34; B: 0.06;95%CI: 0.05,0.07), higher pulse rate (P = 0.003; beta: 0.05; B: 0.02;95%CI: 0.01,0.03), taller body height (P<0.001; beta: 0.11; B: 0.05;95%CI: 0.03,0.07), higher blood concentration of cholesterol (P = 0.003; beta: 0.05; B: 0.17;95%CI: 0.06,0.28) and higher level of education (P = 0.003; beta: 0.09; B: 0.30;95%CI: 0.16,0.45).

Conclusions

IOP was positively associated with estimated CSFP after adjusting for other ocular and systemic parameters. As a corollary, higher estimated CSFP was significantly associated with higher IOP in multivariate analysis. It fits with the notion that the arterial blood pressure, estimated CSFP and IOP are physiologically correlated with each other.     

Body Height,Estimated Cerebrospinal Fluid Pressure and Open-Angle Glaucoma. The Beijing Eye Study 2011

Purpose

To examine potential associations between body height, cerebrospinal fluid pressure (CSFP), trans-lamina cribrosa pressure difference (TLCPD) and prevalence of open-angle glaucoma (OAG) in a population-based setting.

Methods

The population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6±9.8 years (range:50–93 years). A detailed ophthalmic examination was performed. Based on a previous study with lumbar cerebrospinal fluid pressure (CSFP) measurements, CSFP was calculated as CSFP[mmHg] = 0.44×Body Mass Index[kg/m²]+0.16×Diastolic Blood Pressure[mmHg]-0.18×Age[Years]-1.91

Results

Data of IOP and CSFP were available for 3353 (96.7%) subjects. Taller body height was associated with higher CSFP (P<0.001; standardized correlation coefficient beta:0.13; regression coefficient B:0.29; 95% confidence interval (CI):0.25,0.33) after adjusting for male gender, urban region of habitation, higher educational level, and pulse rate. If TLCPD instead of CSFP was added, taller body height was associated with lower TLCPD (P<0.001;beta:−0.10;B:−0.20;95%CI:−0.25,−0.15). Correspondingly, higher CSFP was associated with taller body height (P = 0.003;beta:0.02;B:0.01;95%CI:0.00,0.02), after adjusting for age, gender, body mass index, pulse, systolic blood pressure, and blood concentration of cholesterol. If IOP was added to the model, higher CSFP was associated with higher IOP (P<0.001;beta:0.02;B:0.02;95%CI:0.01,0.03). TLCPD was associated with lower body height (P = 0.003;beta:−0.04;B −0.02,95%CI:−0.04,−0.01) after adjusting for age, body mass index, systolic blood pressure, pulse, blood concentrations of triglycerides, axial length, central corneal thickness, corneal curvature radius, and anterior chamber depth. Adding the prevalence of OAG to the multivariate analysis revealed, that taller body height was associated with a lower OAG prevalence (P = 0.03;beta:−0.03;B:−1.20;95%CI:−2.28,−0.12) after adjusting for educational level and gender.

Conclusions

Taller body height was associated with higher CSFP and lower TLCPD (and vice versa), after adjusting for systemic and ocular parameters. Parallel to the associations between a higher prevalence of glaucoma with a lower CSFP or higher TLCPD, taller body height was associated with a lower prevalence of OAG.     

Ten-Year Cumulative Incidence of Diabetic Retinopathy. The Beijing Eye Study 2001/2011

Objective

To assess the cumulative 10-year incidence of diabetic retinopathy (DR) and its associated factors in a population living in Greater Beijing.

Methods

The population-based longitudinal Beijing Eye Study, which included 4439 subjects (age in 2001: 40+years) in 2001, was repeated in 2011 with 2695 subjects participating (66.4% of the survivors). The study participants underwent a detailed ophthalmic examination. Fundus photographs were examined for the new development of DR.

Results

After excluding individuals with DR at baseline (n = 87) or no sufficient fundus photographs in 2011 (n = 6), the study included 2602 subjects with a mean age of 64.6±9.7 years (median: 64.0 years; range: 50 to 93 years). In the 10-year period, 109 subjects (39 men) developed new DR with an incidence of 4.2% (95% confidence interval (CI): 3.45,5.03). In multiple logistic regression analysis, incident DR was significantly associated with higher HbA1c value (P<0.001; Odds Ratio (OR): 1.73; 95% Confidence Interval (CI): 1.35,2.21), longer duration of diabetes mellitus (P<0.001; OR: 1.16; 95% CI: 1.10,1.22), higher serum concentration of creatinine (P = 0.02; OR: 1.01; 95% CI: 1.002,1.022), lower educational level (P = 0.049; OR: 0.74; 95% CI: 0.55,0.99), higher estimated cerebrospinal fluid pressure (P = 0.038; OR: 1.10; 95% CI: 1.01,1.22), and shorter axial length (P<0.001; OR: 0.48; 95% CI: 0.33,0.71).

Conclusions

The cumulative 10-year incidence (mean: 4.2%) of DR in a North Chinese population was significantly associated with a higher HbA1c value, longer known duration of diabetes mellitus, higher estimated CSFP and shorter axial length (P<0.001). Shorter axial length (or hyperopia) and, potentially, higher CSFP may be additional risk factors to be taken into account when counseling and treating patients with diabetes mellitus.     

Localized Retinal Nerve Fiber Layer Defects Detected by Optical Coherence Tomography: The Beijing Eye Study

Objective

To assess the prevalence of localized retinal nerve fiber layer defects (LRNFLD) and associated factors in adult Chinese.

Methods

The population-based Beijing Eye Study 2011 included 3468 individuals (mean age: 64.6±9.8 years (range: 50–93 years)). The study participants underwent a detailed ophthalmological examination including spectral-domain optical coherence tomography (Spectralis^R-OCT) assisted measurement of the RNFL. A LRNFLD was defined as a sector in which the RNFL contour line dipped into the red zone for a length of <180°.

Results

Readable OCT images were available for 3242 (93.5%) subjects. LRNFLDs were detected in 640 eyes (9.9±0.4%) of 479 subjects (14.8±0.6%). In the age groups of 50–59 years, 60–69 years, 70–79 years, and 80+ years, the prevalence of LRNFLD per person increased from 9.9±0.9%, 11.6±1.0% and 20.6±1.4% to 33.0±3.2%, respectively. In multivariate analysis, prevalence of LRNFLDs was significantly associated with older age (P = 0.001; Odds Ratio (OR): 1.03; 95% Confidence Interval (CI): 1.01,1.05), myopic refractive error (P<0.001;OR:0.79;95%CI:0.74,0.85), larger beta zone of parapapillary atrophy (P<0.001; OR:1.34;95%CI:1.20,1.50), presence of glaucomatous optic neuropathy (P<0.001;OR:7.02;95%CI:3.87,12.7), presence of non-glaucomatous optic nerve damage (P = 0.001;OR:43.3;95%CI:8.24,227.1), and presence of diabetic retinopathy (P = 0.003;OR:2.79;95%CI:1.43,5.44).

Conclusions

OCT-defined LRNFLDs were present in a prevalence of 14.8±0.6% in a population-based study sample of subjects aged 50+ years. Prevalence of LRNFLDs increased with higher age, myopic refractive error, and larger parapapillary beta zone. Major ocular diseases associated with LRNFLs were glaucoma, non-glaucomatous optic nerve damage and diabetic retinopathy. These data may be helpful for a semiautomatic assessment of the RNFL.     

Ocular Hypertension: General Characteristics and Estimated Cerebrospinal Fluid Pressure. The Beijing Eye Study 2011

Purpose

To examine characteristics of ocular hypertensive subjects and potential associations with estimated cerebrospinal fluid pressure (estCSFP).

Methods

The population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6±9.8 years. Ocular hypertension was defined as intraocular pressure (IOP) >21 mmHg, normal optic nerve head appearance and normal retinal nerve fiber layer thickness. IOP was corrected for its dependence on central corneal thickness (CCT) and corneal curvature radius. Estimated CSFP was calculated as CSFP [mmHg] = 0.44×Body Mass Index [kg/m²]+0.16×Diastolic Blood Pressure [mmHg]−0.18×Age [Years]−1.91. Estimated trans-lamina cribrosa pressure difference (estTLCPD) was IOP–estCSFP.

Results

EstCSFP (10.5±3.6 mmHg versus 9.0±3.7 mmHg; P = 0.003) and estTLCPD (12.0±4.4 mmHg versus 5.4±3.8 mmHg; P<0.001) were higher in the ocular hypertensive group than in the normotensive group. In binary regression analysis, ocular hypertension was associated with increased estCSFP (P = 0.03; odds ratio (OR): 1.08; 95% confidence interval (CI): 1.01, 1.17) after adjusting for prevalence of arterial hypertension (P = 0.07; OR: 1.79; 95%CI: 0.96, 3.34), retinal nerve fiber layer thickness (P = 0.03; OR: 0.97; 95%CI: 0.95, 0.997) and blood glucose concentration (P = 0.006; OR: 1.17; 95%CI: 1.04, 1.30).

Conclusions

Ocular hypertensive subjects (with IOP correction for CCT and corneal curvature) as compared to ocular normotensive subjects had a significantly higher estCSFP in univariate analysis and in multivariate analysis. Despite of a higher estCSFP, estTLCPD was still markedly higher in ocular hypertensive eyes than in ocular normotensive eyes.     

Five-Year Change in Intraocular Pressure Associated with Changes in Arterial Blood Pressure and Body Mass Index. The Beijing Eye Study

Purpose

To examine a potential association between longitudinal changes in intraocular pressure (IOP), arterial blood pressure and body mass index (BMI) in a population-based setting.

Methods

The longitudinal population-based Beijing Eye Study included 2355 subjects with an age of 45+ years who were examined in 2006 and in 2011. The participants underwent a detailed ophthalmic examination including tonometry and measurement of arterial blood pressure and BMI.

Results

Data on IOP, arterial blood pressure and BMI measured in 2006 and in 2011 were available for 2257 (95.8%) subjects with a mean age of 59.5±9.7 years. The mean change in IOP was −1.25±2.26 mm Hg, mean change in mean blood pressure −7.4±12.1 mmHg, and mean change in BMI was 0.01±2.04 kg/m². In multivariate analysis, the 5-year change in IOP was significantly associated with a higher change in mean blood pressure (P<0.001; standardized regression coefficient Beta:0.11; regression coefficient B:0.02; 95% confidence interval (CI):0.01,0.03) after adjusting for younger age (P<0.001;Beta:−0.18;B:−0.04;95% CI:−0.05,−0.03), shorter body stature (P = 0.002;Beta:−0.06;B:−0.06;95% CI:−0.03,−0.01), thicker central corneal thickness (P<0.001;Beta:0.19;B:0.02;95% CI:0.01,0.02), deeper anterior chamber depth (P = 0.01;Beta:0.05;B:0.33;95% CI:0.07,0.60), and lower intraocular pressure at baseline (P<0.001;Beta:−0.56;B:−0.42;95% CI:−0.45,−0.39). If the analysis included only longitudinal parameters, the change in IOP was significantly associated with a higher change in mean arterial blood pressure (P<0.001;Beta:0.10;B:0.02;95% CI:0.01,0.03) and a higher change in body mass index (P<0.04;Beta:0.04;B:0.04;95% CI:0.01,0.09).

Conclusions

In the 5-year follow-up of our population-based sample, a change in IOP was associated with a corresponding change in arterial blood pressure and with a corresponding change in body mass index. These longitudinal data support the notion of a physiological relationship between arterial blood pressure, intraocular pressure and body mass index. These findings may be of interest for the discussion of the pathogenesis of glaucomatous optic neuropathy.     

Naloxone for Severe Traumatic Brain Injury: A Meta-Analysis

Objective

The efficiency of naloxone for the management of secondary brain injury after severe traumatic brain injury (sTBI) remains undefined. The aim of this study is to evaluate the current evidence regarding the clinical efficiency and safety of naloxone as a treatment for sTBI in mainland China.

Methodology/Principal Findings

A systematic search of the China Biology Medicine disc (CBM), China Science and Technology Journal Database (VIP), China National Knowledge Internet (CNKI), and Wan Fang Database was performed to identify randomized controlled trials (RCTs) of naloxone treatment for patients with sTBI in mainland China. The quality of the included trials was assessed, and the RevMan 5.1 software was employed to conduct this meta-analysis. Nineteen RCTs including 2332 patients were included in this study. The odds ratio (OR) showed statistically significant differences between the naloxone group and the control group (placebo) in terms of mortality at 18 months after treatment (OR, 0.51, 95%CI: 0.38–0.67; p<0.00001), prevalence of abnormal heart rates (OR, 0.30, 95%CI: 0.21–0.43; p<0.00001), abnormal breathing rate (OR, 0.25, 95%CI: 0.17–0.36; p<0.00001) at discharge, the level of intracranial pressure at discharge (OR, 2.00, 95%CI: 1.41–2.83; p = 0.0001), verbal or physical dysfunction rate (OR, 0.65, 95%CI: 0.43–0.98; p = 0.04), and severe disability rate (OR, 0.47, 95%CI: 0.30–0.73; p = 0.0001) at 18 months after the treatment. The mean difference (MD) showed statistically significant differences in awakening time at discharge (MD, −4.81, 95%CI: −5.49 to −4.12; p<0.00001), and GCS at 3 days (MD, 1.00, 95%CI: 0.70–1.30; p<0.00001) and 10 days (MD, 1.76, 95%CI: 1.55–1.97; p<0.00001) after treatment comparing naloxone with placebo group.

Conclusions/Significance

This study indicated that applying naloxone in the early stage for sTBI patients might effectively reduce mortality, control intracranial pressure (ICP), and significantly improve the prognosis.     

Prevalence and Associated Factors for Pterygium in Rural Agrarian Central India. The Central India Eye and Medical Study

Purpose

To evaluate the prevalence of pterygia and associated factors in a rural population in a mostly undeveloped agrarian region.

Methods

The Central India Eye and Medical Study is a population-based study performed in a rural region of Central India. The study comprised 4711 subjects (aged 30+ years). A detailed ophthalmic and medical examination was performed. A pterygium was diagnosed during the slit lamp examination and confirmed on corneal photographs. It was defined as a fleshy fibrovascular growth, crossing the limbus and typically seen on the nasal, and sometimes temporal, conjunctiva.

Results

A pterygium was detected in 798 eyes (prevalence rate: 8.47±0.29%) of 608 (12.91±0.49%) subjects. Bilateral pterygia were present in 190 subjects (4.0% of study population). Pterygia prevalence increased from 6.7±0.8% in the age group 30-39 years, to 13.5±1.2% in the age group 50-59 years, to 25.3±2.1% in the age group 70-79 years. Prevalence of pterygia was associated with older age (P<0.001; regression coefficient B: 0.02; odds ratio (OR): 1.02; 95%CI: 1.01, 1.03), male gender (P<0.001;B:-0.73;OR: .48;95%CI:0.39,0.61), lower level of education (P<0.001;B:-0.30;OR:0.74;95%CI:0.69,0.80), lower body height (P=0.001;B:-0.02;OR:0.98;95%CI:0.97,0.99), and higher cylindrical refractive error (P<0.001;B:0.23;OR:1.26;95%CI:1.18,1.34). If the education level was dropped, the number of hours spent with vigorous activity outdoors (P=0.001;B:0.001;OR:1.001;95%CI:1.000,1.0001) was significantly associated with the prevalence of pterygia, in addition to older age (P<0.001;B:0.03;OR:1.03;95%CI:1.03,1.04), male gender (P<0.001;B:-0.49;OR:0.62;95%CI:0.49,0.77), lower body height (P=0.005;B:-0.02;OR:0.98;95%CI:0.97,0.99), and higher cylindrical refractive error (P<0.001;B:0.23;OR:1.25;95%CI:1.18,1.34).

Conclusions

Pterygium prevalence in rural Central India is about 13% among adult Indians aged 30+ years. Older age, male gender, lower educational level, lower body height and more time spent outdoors with vigorous work were associated factors. Since the living conditions in the study location were mostly untouched by modern developments, the results may show the prevalence and associations of pterygia without major medical or technologic influences.     

Refractive Error,Visual Acuity and Causes of Vision Loss in Children in Shandong,China. The Shandong Children Eye Study

Purpose

To examine the prevalence of refractive errors and prevalence and causes of vision loss among preschool and school children in East China.

Methods

Using a random cluster sampling in a cross-sectional school-based study design, children with an age of 4–18 years were selected from kindergartens, primary schools, and junior and senior high schools in the rural Guanxian County and the city of Weihai. All children underwent a complete ocular examination including measurement of uncorrected (UCVA) and best corrected visual acuity (BCVA) and auto-refractometry under cycloplegia. Myopia was defined as refractive error of ≤−0.5 diopters (D), high myopia as ≤−6.0D, and amblyopia as BCVA ≤20/32 without any obvious reason for vision reduction and with strabismus or refractive errors as potential reasons.

Results

Out of 6364 eligible children, 6026 (94.7%) children participated. Prevalence of myopia (overall: 36.9±0.6%;95% confidence interval (CI):36.0,38.0) increased (P<0.001) from 1.7±1.2% (95%CI:0.0,4.0) in the 4-years olds to 84.6±3.2% (95%CI:78.0,91.0) in 17-years olds. Myopia was associated with older age (OR:1.56;95%CI:1.52,1.60;P<0.001), female gender (OR:1.22;95%CI:1.08,1.39;P = 0.002) and urban region (OR:2.88;95%CI:2.53,3.29;P<0.001). Prevalence of high myopia (2.0±0.2%) increased from 0.7±0.3% (95%CI:0.1,1.3) in 10-years olds to 13.9±3.0 (95%CI:7.8,19.9) in 17-years olds. It was associated with older age (OR:1.50;95%CI:1.41,1.60;P<0.001) and urban region (OR:3.11;95%CI:2.08,4.66);P<0.001). Astigmatism (≥0.75D) (36.3±0.6%;95%CI:35.0,38.0) was associated with older age (P<0.001;OR:1.06;95%CI:1.04,1.09), more myopic refractive error (P<0.001;OR:0.94;95%CI:0.91,0.97) and urban region (P<0.001;OR:1.47;95%CI:1.31,1.64). BCVA was ≤20/40 in the better eye in 19 (0.32%) children. UCVA ≤20/40 in at least one eye was found in 2046 (34.05%) children, with undercorrected refractive error as cause in 1975 (32.9%) children. Amblyopia (BCVA ≤20/32) was detected in 44 (0.7%) children (11 children with bilateral amblyopia).

Conclusions

In coastal East China, about 14% of the 17-years olds were highly myopic, and 80% were myopic. Prevalence of myopia increased with older age, female gender and urban region. About 0.7% of pre-school children and school children were amblyopic.     

Pseudoexfoliation: Normative Data and Associations. The Central India Eye and Medical Study

Purpose

To assess the prevalence of pseudoexfoliation (PEX) and its associations in a population-based setting.

Design

Population-based, cross-sectional study.

Methods

The Central India Eye and Medical Study included 4711 individuals. All study participants underwent a detailed ophthalmological examination. After medical pupil dilation, PEX was assessed by an experienced ophthalmologist using slit-lamp based biomicroscopy.

Results

Slit lamp examination results were available for 4646 (98.6%) study participants with a mean age of 49.3±13.3 years (range: 30–100 years). PEX was detected in 87 eyes (prevalence: 0.95±0.10% (95%CI: 0.75, 1.15) of 69 subjects (prevalence: 1.49±0.18% (95%CI: 1.14, 1.83). PEX prevalence increased significantly (P<0.001) from 0% in the age group of 30–39 years, to 2.85±0.56% in the age group of 60–69 years, to 6.60±1.21% in the age group of 70–79 years, and to 12.3±4.11% in the age group of 80+ years. In multivariate analysis, PEX prevalence was associated with higher age (P<0.001; regression coefficient B:0.11; odds ratio (OR): 1.11 (95%CI: 1.09, 1.13)), lower body mass index (P = 0.001; B: −0.12; OR: 0.88 (95CI: 0.82, 0.95)) and higher diastolic blood pressure (P = 0.002; B: 0.02; OR: 1.03 (95%CI: 1.01, 1.04)). In the multivariate analysis, PEX was not associated with retinal nerve fiber layer cross section area (P = 0.76) and presence of open-angle glaucoma (P = 0.15).

Conclusions

In a rural Central Indian population aged 30+ years, PEX prevalence (mean: 1.49±0.18%) was significantly associated with older age, lower body mass index and higher diastolic blood pressure. It was not significantly associated with optic nerve head measurements, refractive error, any ocular biometric parameter, nuclear cataract, early age-related macular degeneration and retinal vein occlusion, diabetes mellitus, smoking, and dyslipidemia.     

Prevalence and Associations of Incomplete Posterior Vitreous Detachment in Adult Chinese: The Beijing Eye Study

Purpose

To determine prevalence and associations of incomplete posterior vitreous detachment (PVD).

Methods

The population-based cross-sectional Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6±9.8 years (range: 50–93 years). A detailed ophthalmic examination was performed including spectral-domain optical coherence tomography (SD-OCT). Incomplete PVD was differentiated into type 1 (shallow PVD with circular perifoveal vitreous attachment), type 2 (PVD reaching fovea but not foveola), type 3 (shallow PVD with pinpoint vitreous attachment at the foveola), and type 4 (PVD completely detached from the macula, attached to the optic disc).

Results

An incomplete PVD was detected in 3948 eyes (prevalence: 60.5±0.6%; 95% Confidence Interval (CI): 59.3%,61.7%) of 2198 subjects (67.1±0.8%;95%CI: 65.6%,68.7%). Type 1 PVD was seen in 3090 (78.3%) eyes, type 2 PVD in 504 (12.8%) eyes, type 3 PVD in 70 (1.8%) eyes, and type 4 PVD in 284 (7.2%) eyes. Prevalence of incomplete PVD was associated with younger age (P<0.001;OR:0.91), male gender (P<0.001;OR:0.64), rural region of habitation (P<0.001;OR:0.49), larger corneal diameter (P = 0.04;OR:0.91), better best corrected visual acuity (P = 0.02;OR:0.41), and hyperopic refractive error (P<0.001;OR:1.15). The type of incomplete PVD was associated with higher age (P<0.001), urban region of habitation (P<0.001), myopic refractive error (P = 0.001), thinner cornea (P = 0.005), and better best corrected visual acuity (P = 0.056).

Conclusions

In adult Chinese in Greater Beijing, prevalence of an incomplete PVD (detected in 67.1% subjects) was associated with younger age, male gender, rural region of habitation, larger corneal diameter, better best corrected visual acuity and hyperopic refractive error.     

Role of Toll-Like Receptor 4 in Colorectal Carcinogenesis: A Meta-Analysis

Objective

This meta-analysis was performed to evaluate the role of toll-like receptor 4 (TLR-4) in colorectal carcinogenesis.

Methods

The PubMed, CISCOM, CINAHL, Web of Science, Google Scholar, EBSCO, Cochrane Library, and CBM databases were searched from inception through November 1st, 2013 without language restrictions. Odds ratios (ORs) or standardized mean differences (SMD) with their 95% confidence intervals (CI) were calculated.

Results

Fourteen case-control studies met the inclusion criteria for this meta-analysis. A total of 1,209 colorectal cancer (CRC) cases and 1,218 healthy controls were involved in this meta-analysis. Two common polymorphisms (299 A>G and 399 C>T) in the TLR-4 gene, TLR-4 mRNA and protein expression were assessed. Our meta-analysis results revealed that the TLR-4 399 C>T polymorphism might increase the risk of CRC (allele model: OR = 1.77, 95%CI = 1.32∼2.36, P<0.001; dominant model: OR = 1.83, 95%CI = 1.32∼2.52, P<0.001; respectively). However, we found no correlation between the TLR-4 299 A>G polymorphism and CRC risk (all P>0.05). A subgroup analysis by ethnicity suggested that TLR-4 genetic polymorphisms were associated with an increased risk of CRC among Asians (allele model: OR = 1.50, 95%CI = 1.19∼1.88, P = 0.001; dominant model: OR = 1.49, 95%CI = 1.16∼1.92, P = 0.002; respectively), but not among Caucasians and Africans (all P>0.05). Furthermore, our results showed that TLR-4 mRNA and protein levels in CRC patients were higher than those in healthy controls (TLR-4 mRNA: SMD  = 2.51, 95%CI  = 0.98∼4.05, P = 0.001; TLR-4 protein: OR  = 4.75, 95%CI  = 1.16∼19.36, P = 0.030; respectively).

Conclusion

Our findings provide empirical evidence that TLR-4 may play an important role in colorectal carcinogenesis. Thus, TLR-4 is a promising potential biomarker for the early diagnosis of CRC.     

Effect of Cycloplegia on the Refractive Status of Children: The Shandong Children Eye Study

PurposeTo determine the effect of 1% cyclopentolate on the refractive status of children aged 4 to 18 years.MethodsUsing a random cluster sampling in a cross-sectional school-based study design, children with an age of 4–18 years were selected from kindergardens, primary schools, junior and senior high schools in a rural county and a city. Auto-refractometry was performed before and after inducing cycloplegia which was achieved by 1% cyclopentolate eye drops.ResultsOut of 6364 eligible children, data of 5999 (94.3%) children were included in the statistical analysis. Mean age was 10.0±3.3 years (range: 4–18 years). Mean difference between cycloplegic and non-cycloplegic refractive error (DIFF) was 0.78±0.79D (median: 0.50D; range: -1.00D to +10.75D). In univariate analysis, DIFF decreased significantly with older age (P<0.001;correlation coefficient r:-0.24), more hyperopic non-cycloplegic refractive error (P<0.001;r = 0.13) and more hyperopic cycloplegic refractive error (P<0.001;r = 0.49). In multivariate analysis, higher DIFF was associated with higher cycloplegic refractive error (P<0.001; standardized regression coefficient beta:0.50; regression coefficient B: 0.19; 95% confidence interval (CI): 0.18, 0.20), followed by lower intraocular pressure (P<0.001; beta: -0.06; B: -0.02; 95%CI: -0.03, -0.01), rural region of habitation (P = 0.001; beta: -0.04; B: -0.07; 95%CI: -0.11, -0.03), and, to a minor degree, with age (P = 0.006; beta: 0.04; B: 0.009; 95%CI: 0.003, 0.016). 66.4% of all eyes with non-cycloplegic myopia (≤-0.50D) remained myopic after cycloplegia while the remaining 33.6% of eyes became emmetropic (18.0%) or hyperopic (15.7%) under cycloplegia. Prevalence of emmetropia decreased from 37.5% before cycloplegia to 19.8% after cycloplegia while the remaining eyes became hyperopic under cycloplegia.ConclusionsThe error committed by using non-cycloplegic versus cycloplegic refractometry in children with mid to dark-brown iris color decreased with older age, and in parallel manner, with more myopic cycloplegic refractive error. Non-cycloplegic refractometric measures lead to a misclassification of refractive error in a significant proportion of children.     

Adiponectin-11377CG Gene Polymorphism and Type 2 Diabetes Mellitus in the Chinese Population: A Meta-Analysis of 6425 Subjects

Background

Although adiponectin −11377CG gene polymorphism is implied to be associated with increased type 2 diabetes mellitus (T2DM) risk, results of individual studies are inconsistent.

Objective and Methods

A meta-analysis consisting of 12 individual studies, including a total of 6425 participants, was carried out in order to investigate the association of adiponectin −11377CG gene polymorphism with T2DM. The pooled odds ratio (OR) and its corresponding confidence interval (CI) at 95% were assessed through the random- or fixed- effect model.

Results

A significant relationship was observed between adiponectin −11377CG gene polymorphism and T2DM under allelic (OR: 1.150, 95% CI: 1.060 to 1.250, P = 0.001), recessive (OR: 1.450, 95% CI: 1.180–1.770, P = 0.0004), dominant (OR: 1.071, 95% CI: 1.013–1.131, P = 0.015), additive (OR: 1.280, 95% CI: 1.090–1.510, P = 0.002), and homozygous genetic models (OR: 1.620, 95% CI: 1.310–1.990, P<0.00001). No significant association was found between them under the heterozygous genetic model (OR: 1.640, 95% CI: 0.850–3.170, P = 0.140).

Conclusions

Adiponectin −11377CG gene polymorphism was significantly associated with T2DM risk susceptibility. G allele carriers are predisposed to T2DM risk.     

The Effect of Periodontal Treatment on Hemoglobin A1c Levels of Diabetic Patients: A Systematic Review and Meta-Analysis

Background

There is growing evidence that periodontal treatment may affect glycemic control in diabetic patients. And several systematic reviews have been conducted to assess the effect of periodontal treatment on diabetes outcomes. Researches of this aspect are widely concerned, and several new controlled trials have been published. The aim of this study was to update the account for recent findings.

Methods

A literature search (until the end of January 2014) was carried out using various databases with language restriction to English. A randomized controlled trial (RCT) was selected if it investigated periodontal therapy for diabetic subjects compared with a control group received no periodontal treatment for at least 3 months of the follow-up period. The primary outcome was hemoglobin A1c (HbA1c), and secondary outcomes were periodontal parameters included probing pocket depth (PPD) and clinical attachment level (CAL).

Results

Ten trials of 1135 patients were included in the analysis. After the follow-up of 3 months, treatment substantially lowered HbA1c compared with no treatment after periodontal therapy (–0.36%, 95%CI, −0.52% to −0.19%, P<0.0001). Clinically substantial and statistically significant reduction of PPD and CAL were found between subjects with and without treatment after periodontal therapy (PPD −0.42 mm, 95%CI: −0.60 to −0.23, P<0.00001; CAL −0.34 mm, 95%CI: −0.52 to −0.16, P = 0.0002). And there is no significant change of the level of HbA1c at the 6-month comparing with no treatment (–0.30%, 95%CI, −0.69% to 0.09%, P = 0.13).

Conclusions

Periodontal treatment leads to the modest reduction in HbA1c along with the improvement of periodontal status in diabetic patients for 3 months, and this result is consistent with previous systematic reviews. And the effect of periodontal treatment on HbA1c cannot be observed at 6-month after treatment.     

E-Selectin Gene Polymorphisms and Essential Hypertension in Asian Population: An Updated Meta-Analysis

Objective

Epidemiological studies have shown that E-selectin gene polymorphisms (A561C and C1839T) may be associated with essential hypertension (EH), but the results are conflicting in different ethnic populations. Thus, we performed this meta-analysis to investigate a more authentic association between E-selectin gene polymorphisms and the risk of EH.

Methods

We searched the relevant studies for the present meta-analysis from the following electronic databases: PubMed, Embase, Cochrane Library, Google Scholar, Web of Science, Wanfang Data, and China National Knowledge Infrastructure (CNKI). Odds ratios (OR) with 95% confidence interval (CI) were used to evaluate the strength of the association between E-selectin gene polymorphisms and EH susceptibility. The pooled ORs were performed for dominant model, allelic model and recessive model. The publication bias was examined by Begg’s funnel plots and Egger’s test.

Results

A total of eleven studies met the inclusion criteria. All studies came from Asians. Ten studies (12 cohorts) evaluated the A561C polymorphism and EH risk, including 2,813 cases and 2,817 controls. The pooled OR was 2.280 (95%CI: 1.893–2.748, P<0.001) in dominant model, 5.284 (95%CI: 2.679–10.420, P<0.001) in recessive model and 2.359 (95%CI: 1.981–2.808, P = 0.001) in allelic model. Four studies (six cohorts) evaluated C1839T polymorphism and EH risk, including 1,700 cases and 1,681 controls. The pooled OR was 0.785 (95%CI: 0.627–0.983, P = 0.035) in dominant model, 1.250 (95%CI: 0.336–4.652, P = 0.739) in recessive model and 0.805 (95%CI: 0.649–0.999, P = 0.049) in allelic model.

Conclusion

The current meta-analysis concludes that the C allele of E-selectin A561C gene polymorphism might increase the EH risk in Asian population, whereas the T allele of E-selectin C1839T gene polymorphism might decrease the EH risk.     

The Significance of Exo1 K589E Polymorphism on Cancer Susceptibility: Evidence Based on a Meta-Analysis

The exonuclease1 (Exo1) gene is a key component of mismatch repair (MMR) by resecting the damaged strand, which is the only exonuclease involved in the human MMR system. The gene product is a member of the RAD2 nuclease family and functions in DNA replication, repair and recombination. However, whether Exo1 is required to activate MMR-dependent DNA damage response (DDR) remains unknown, the conclusions of the Exo1 polymorphisms on cancer susceptibility studies were not consistent. We carried out a meta-analysis of 7 case-control studies to clarify the association between the Exo1 K589E polymorphism and cancer risk. Overall,a significant association of the Exo1 K589E polymorphism with cancer risk in all genetic models (Lys vs Glu: OR = 1.51, 95%CI:1.39–1.99, P<0.01; Glu/Lys vs Glu/Glu: OR = 1.43, 95%CI:1.28–1.60, P<0.01; Lys/Lys vs Glu/Glu: OR = 2.45, 95%CI:1.90–3.17, P<0.01; Lys/Lys+Glu/Lys vs Glu/Glu: OR = 1.53, 95%CI:1.38–1.71, P<0.01; Glu/Glu vs Glu/Lys+Lys/Lys: OR =  2.27, 95%CI:1.79–2.89, P<0.01). In the stratified analysis by ethnicity, significantly increased risk was observed in Asian population (Lys vs Glu: OR = 1.53, 95%CI:1.39–1.69, P<0.01; Glu/Lys vs Glu/Glu: OR = 1.50, 95%CI:1.34–1.69, P<0.01; Lys/Lys vs Glu/Glu: OR = 2.48, 95%CI:1.84–3.34, P<0.01; Lys/Lys+Glu/Lys vs Glu/Glu: OR = 1.58, 95%CI:1.41–1.78, P<0.01; Glu/Glu vs Glu/Lys+Lys/Lys: OR = 2.18, 95%CI:1.62–2.93, P<0.01). Subgroup analysis based on smoking suggested Exo1 K589E polymorphism conferred significant risk among smokers (Lys/Lys+Glu/Lys vs Glu/Glu: OR = 2.16, 95%CI:1.77–2.63, P<0.01), but not in non-smokers (Lys/Lys+Glu/Lys vs Glu/Glu: OR = 0.89, 95%CI:0.64–1.24, P = 0.50). In conclusion, Exo1 K589E Lys allele may be used as a novel biomarker for cancer susceptibility, particularly in smokers.