[Show abstract][Hide abstract] ABSTRACT: To determine the prevalence and risk factors of pre-diabetes, diagnosed and undiagnosed diabetes mellitus in rural Bangladesh.
Using a population-based cluster random sampling strategy, 3104 adults aged 30 years or older were recruited. Fasting capillary blood glucose, blood pressure (BP), height, weight, waist circumference, and Knowledge, Attitudes and Practice (KAP) related to diabetes were recorded. Diabetes Mellitus (DM) was defined as fasting glucose ≥7.0 mmol/L or self-reported diagnosed diabetes and impaired fasting glucose as fasting glucose (IFG) ≥6.1 and <7.0 mmol/L.
The overall crude prevalence of DM was 7.2% (95% confidence interval (CI) 6.3-8.1%; n=222) of which 55% (n=123) was previously undiagnosed (UDM). The prevalence of IFG was 5.3% (95% CI 4.5-6.1%; n=163). Age standardized prevalence of DM was 6.6% and of IFG 5.0%. UDM was higher in people with lower socio-economic status (59% versus 31%; p<0.001). Of those with known DM 56% had poor glycaemic control (fasting glucose ≥7.0 mmol/L) and 37% were not on medication. Overall knowledge of DM was poor. For example, only 16.3% with UDM, 17.8% with IFG, and 13.4% with normal fasting glucose knew that diabetes causes eye disease compared to 55.6% people with KDM (p<0.001 for trend).
In this rural Bangladeshi community, the percentage of UDM was high and lower socioeconomic status was associated with a higher risk of UDM. Overall knowledge of DM was poor. Public health programmes should target those of low socioeconomic status and aim at increasing knowledge of DM in rural Bangladesh.
This article is protected by copyright. All rights reserved.
Journal of Diabetes 08/2015; DOI:10.1111/1753-0407.12294 · 2.35 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Diabetic retinopathy is a serious complication of diabetes mellitus and can lead to blindness. A genetic component, in addition to traditional risk factors, has been well described although strong genetic factors have not yet been identified. Here, we aimed to identify novel genetic risk factors for sight-threatening diabetic retinopathy using a genome-wide association study.
Retinopathy was assessed in white Australians with type 2 diabetes mellitus. Genome-wide association analysis was conducted for comparison of cases of sight-threatening diabetic retinopathy (n = 336) with diabetic controls with no retinopathy (n = 508). Top ranking single nucleotide polymorphisms were typed in a type 2 diabetes replication cohort, a type 1 diabetes cohort and an Indian type 2 cohort. A mouse model of proliferative retinopathy was used to assess differential expression of the nearby candidate gene GRB2 by immunohistochemistry and quantitative western blot.
The top ranked variant was rs3805931 with p = 2.66 × 10(-7), but no association was found in the replication cohort. Only rs9896052 (p = 6.55 × 10(-5)) was associated with sight-threatening diabetic retinopathy in both the type 2 (p = 0.035) and the type 1 (p = 0.041) replication cohorts, as well as in the Indian cohort (p = 0.016). The study-wide meta-analysis reached genome-wide significance (p = 4.15 × 10(-8)). The GRB2 gene is located downstream of this variant and a mouse model of retinopathy showed increased GRB2 expression in the retina.
Genetic variation near GRB2 on chromosome 17q25.1 is associated with sight-threatening diabetic retinopathy. Several genes in this region are promising candidates and in particular GRB2 is upregulated during retinal stress and neovascularisation.
[Show abstract][Hide abstract] ABSTRACT: Albuminuria, a marker of diabetic kidney disease, is closely associated with diabetic retinopathy (DR) and diabetic macular edema (DME). However, the relationship between estimated glomerular filtration rate (eGFR) with DR and DME remains unclear, particularly in type 2 diabetes. We investigated the association of eGFR with DR and DME in a sample of patients with type 2 diabetes.
We included 263 Caucasian patients with type 2 diabetes aged ≥18 years who participated in a clinic-based cross-sectional study in Melbourne, Australia. Diabetic retinopathy (n = 140) and DME (n = 61) were assessed from retinal photographs graded using the modified Airlie House classification and further confirmed with optical coherence tomography. Estimated glomerular filtration rate, assessed using the CKD-EPI formula, was analyzed continuously (per SD change) and categorically (normal renal function ≥ 90; impaired renal function, 60-89, and chronic kidney disease [CKD] < 60 mL/min/1.73 m2).
When eGFR was analyzed categorically, impaired renal function and CKD were associated with the presence of DR when compared to normal renal function in multivariable models (odds ratio [OR] with 95% confidence interval [CI] of 2.97 [1.12-7.87] and 3.77 [1.28-11.10]), respectively. In DR severity analyses, CKD showed significant associations with moderate (5.83 [1.44-23.5], P-trend = 0.02) and severe DR (4.91 [1.26-19.0], P-trend = 0.04). These associations persisted when eGFR was analyzed continuously (P = 0.04). No significant associations were found between eGFR and DME.
Our results suggest that lower levels of eGFR were associated with the presence and severity of DR, but not with DME.
[Show abstract][Hide abstract] ABSTRACT: Purpose/Aim: To investigate the association between retinal vascular tortuosity and traditional- and vascular-related risk factors in persons with diabetes.
We recruited 224 diabetic patients. Retinal vascular tortuosity was measured from fundus photographs. Association of tortuosity with the following factors was assessed after adjusting for significant co-factors: diabetes duration, HbA1c, systolic blood pressure (SBP), cholesterol and body mass index (BMI), flicker-light induced retinal vasodilatation, and markers of endothelial function and inflammation (skin microvacular responses to acetylcholine iontophoresis, soluble e-selectin, inter-cellular adhesion molecule-1, vascular cell adhesion molecule-1, endothelin-1, total nitrite, C-reactive protein).
Adjusting for age and gender, longer diabetes duration was associated with more tortuous retinal arterioles (mean difference in arteriolar tortuosity 5.85 × 10(-5), 95% Confidence Interval 1.44-10.3 × 10(-5); p = 0.016; ≤10 versus >10 years duration). Reduced flicker-light induced retinal vasodilatation was associated with tortuous arterioles and venules (mean difference in arteriolar tortuosity 5.62 × 10(-5), 4.50-6.72 × 10(-5); p < 0.001 and in venules 5.94 × 10(-5), 3.33-8.55 × 10(-5); p < 0.001; comparing highest versus lowest tertile of flicker-light vasodilatation). These associations remained after adjusting for co-factors. Diabetes duration explained about 36% and flicker-light vasodilatation 25% of the variation in retinal arteriolar tortuosity. No associations were found between retinal arteriolar or venular tortuosity and HBA1c, SBP, cholesterol, BMI and serum markers of endothelial function.
Increased retinal arteriolar tortuosity was related to longer diabetes duration and reduced flicker-light induced vasodilatory response, suggesting that retinal vascular tortuosity in adults with diabetes may be influenced by multiple diabetes-related physio-pathological changes.
Current eye research 06/2015; DOI:10.3109/02713683.2015.1034371 · 1.66 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To determine the prevalence and risk factors of undiagnosed diabetic retinopathy (DR), in particular vision-threatening DR (VTDR) in a multiethnic Asian cohort.
A population-based survey of 3353 Chinese, 3280 Malays and 3400 Indians (73.6% response) aged 40-80 years residing in Singapore. Diabetes mellitus (DM) was defined as random glucose ≥11.1 mmol/L, use of diabetic medication or a previous physician diagnosis. DR severity was graded from retinal photographs following the modified Airlie House classification. VTDR was defined as the presence of severe non-proliferative DR (NPDR), proliferative DR (PDR) or clinically significant macular oedema (CSMO), using the Eye Diseases Prevalence Research Group definition. Participants were deemed 'undiagnosed' if they reported no prior physician diagnosis in structured interviews, in those with the condition.
Of 10 033 participants, 2376 had DM (23.7%), of which 805 (33.9%) had DR. Among 2376 with DM, 11.1% (n=263) were undiagnosed. Among 805 with DR, 671 (83.3%) were undiagnosed. Among 212 with VTDR, 59 (27.3%) were undiagnosed. In multivariate models, factors associated with undiagnosed VTDR were higher low-density lipoprotein (LDL) cholesterol (OR=1.53, 95% CI 0.99 to 2.35, p=0.05) and absence of visual impairment or blindness in any eye in terms of best-corrected vision OR=3.00, 95% CI 1.47 to 6.11, p=0.003).
In this community, a quarter with VTDR is undiagnosed, and 8 in 10 with any DR are undiagnosed, compared with only 1 in 10 with DM undiagnosed. These findings suggest that screening for diabetes is successful, while screening for DR is currently inadequate in our population. Public health strategies to aid early diagnosis of DR in Singapore are urgently warranted to reduce blindness due to diabetes.
Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
The British journal of ophthalmology 05/2015; DOI:10.1136/bjophthalmol-2014-306492 · 2.81 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Blood flow in the retina is intrinsically regulated to meet the metabolic demands of its constituent cells. Flickering light or stationary contrast reversals induce an increase in blood flow within seconds of the stimulus onset. This phenomenon is thought to compensate for an increase in ganglion cell activity and energy consumption. Ganglion cell activity is in turn dependent on signals from photoreceptors, bipolar cells, horizontal cells and amacrine cells. The physiological properties of these neurons determine how each type is affected by a particular light characteristic. Neuronal activity then triggers the release of signalling molecules that dilate local blood vessels and increase blood flow. Nitric oxide has been implicated as an important mediator, but metabolites of arachidonic acid may also be involved. Detailed elucidation of these mechanisms, together with advances in imaging technology, may facilitate the use of neurovascular tests to improve the detection of retinal damage in pathological conditions.
This article is protected by copyright. All rights reserved.
Clinical and Experimental Ophthalmology 03/2015; DOI:10.1111/ceo.12530 · 1.95 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Aims To objectively quantify the thickness of peripapillary choroid using spectral-domain optical coherence tomography (SD-OCT) with enhanced depth imaging (EDI) followed by a novel automated choroidal segmentation software in Asian eyes and to evaluate its systemic and ocular determinants.
Methods We recruited 520 subjects (1040 eyes) from the Singapore Malay Eye Study, a cross-sectional population-based study. Subjects underwent standardised detailed ophthalmic examination including SD-OCT (Spectralis) with EDI for measurement of peripapillary choroidal thickness (PPCT).
Results The mean age of the subjects was 66.7±10.4 years (range 47–88 years) and the mean spherical equivalent was −0.01±2.28 D (range −18.50 to +7.00 D). The intra-session repeatability of PPCT measurements at four quadrants using automated choroidal segmentation software was excellent (intraclass correlation coefficient 0.9998–0.9999). The overall mean PPCT was 136.2±56.8 µm. Peripapillary choroid showed geographical differences among the four quadrants, being thickest in the superior quadrant (150.5±59.6 µm), followed by the nasal (143.5±58.4 µm) and temporal quadrants (139.4±68.9 µm), and thinnest in the inferior quadrant (111.3±51.7 µm). Among the range of ocular and systemic factors studied, shorter axial length (p=0.002), younger age (p=0.018), lower triglyceride level (p=0.015) and the presence of diabetes (p=0.036) were the only significant predictors of thicker peripapillary choroid.
Conclusions Using novel automated choroidal segmentation software, we provide reliable objective measurements of PPCT in a population-based setting. Shorter axial length, younger age, lower triglyceride levels and the presence of diabetes are the factors independently associated with thicker PPCT. These factors should be taken into consideration when interpreting Spectralis EDI SD-OCT-based PPCT measurements in clinics.
British Journal of Ophthalmology 01/2015; 99(7). DOI:10.1136/bjophthalmol-2014-306152 · 2.81 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Purpose. We examined the association of CKD defined by serum creatinine, serum cystatin C, and albuminuria with moderate diabetic retinopathy (DR). Methods. We examined 1,119 Indian adults with diabetes, aged 40–80 years, who participated in the Singapore Indian Eye Study (2007–2009), a population-based cross-sectional study. The associations of CKD defined by each of the three markers alone and in combination with moderate DR were examined using logistic regression models adjusted for potential confounding factors including duration of diabetes, smoking, body mass index, systolic blood pressure, and HbA1c. Results. The prevalence of moderate DR was significantly higher among those with CKD defined by triple markers (41.1%) compared to CKD defined separately by creatinine (26.6%), cystatin C (20.9%), and albuminuria (23.4%). People with CKD defined by triple markers had a fourteenfold higher odds of moderate DR (OR (95% CI) = 13.63 (6.08–30.54)) compared to those without CKD by any marker. Nearly half (48.7%) of participants with cystatin C ≥ 1.12 mg/L have moderate DR. Conclusions. CKD defined by a triple marker panel was strongly associated with moderate DR in this Asian population with diabetes.
Journal of Diabetes Research 01/2015; · 3.54 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To investigate the acceptance and preferences rates of 3 sustained drug delivery systems in glaucoma patients.
A cross-sectional study involving 250 Chinese patients recruited from outpatient glaucoma clinics in Singapore using an interviewer-administered survey. Beliefs toward medicines, eye drops, illness perception, medication adherence, and health literacy were assessed using validated questionnaires. After receiving standard information on the 3 sustained drug delivery systems, that is, subconjunctival, intracameral, and punctal routes; each route's acceptance and attitudes were determined.
The subconjunctival (acceptance: 61.6%, n=154), intracameral (acceptance: 57.2%, n=143), and punctal (acceptance: 63.2%, n=158) routes were willing to be accepted by the majority of the interviewed patients. Among those, 78.6%, 79.1%, and 78.5% were willing to pay an equal or higher cost compared with their current eye drops for the subconjunctival, intracameral, and punctal plug routes, respectively. Independent factors associated with the acceptance for subconjunctival, intracameral, and punctal plug routes included: male sex (P=0.007, 0.014, 0.046, respectively), patients not on health care subsidies (P=0.022, 0.002, 0.016, respectively), and bilateral glaucoma disease (P=0.003, 0.013, 0.004, respectively). A total of 120 (48.0%) patients ranked punctal plug placement as the preferred route for sustained drug delivery followed by subconjunctival (n=76, 30.4%) and intracameral (n=54, 21.6%) routes.
Sustained drug delivery for the medical treatment of glaucoma is an acceptable alternative to daily eye drop administration by most Singaporean Chinese individuals in this study. Male patients, nonsubsidized patients, and those with bilateral glaucoma were independently associated with preference of these 3 alternative routes of administration to traditional glaucoma drops.
Journal of Glaucoma 01/2015; Publish Ahead of Print. DOI:10.1097/IJG.0000000000000197 · 2.43 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To investigate the effectiveness of a low vision self-management program (LVSMP) in older adults.Methods Participants(n = 153) were existing clients of a national low vision rehabilitation organisation randomly allocated to usual services (n = 60) or usual services plus LVSMP (n = 93). The LVSMP was an eight-week group program facilitated by low vision counsellors. The primary outcome was vision-specific quality of life (QoL) measured using the Impact of Vision Impairment (IVI) questionnaire. Secondary outcomes emotional well-being, self-efficacy and adaptation to vision loss were measured using the Depression, Anxiety, Stress Scale (DASS), General Self-Efficacy Scale (GSES), and Short Form Adaptation to Age-Related Vision Loss scale (AVL12).ResultsAt one and six month follow-up assessments, no significant between-group differences were found for vision-specific QoL, emotional well-being, adaptation to vision loss or self-efficacy (p > 0.05). Univariate and multivariate analyses revealed no impact of the intervention on outcome measures.Conclusions
In contrast to previous work, our study found limited benefit of a LVSM program on QoL for older adults accessing low vision services.Practice ImplicationsWhen implementing self-management programs in low vision rehabilitation settings, issues of client interest, divergence of need, program accessibility and fidelity of intervention delivery need to be addressed.