Search

To determine the prevalence of vision impairment (VI) and blindness and their determinants in the elderly population of Tehran. In a cross-sectional study, multi-stage cluster sampling was used to select a sample of over 60 year population of Tehran. Optometric examinations included the measurement of uncorrected visual acuity, objective and subjective refraction, presenting and best corrected visual acuity. Vision impairment is reported according to the WHO definition. Visual acuity worse than 20/60 and 20/400 in the better eye was regarded as low vision and blindness, respectively. According to presenting visual acuity, VI was found in 14.8% (95%CI: 13.1–16.5) of the participants, including low vision in 13.8% (95%CI: 12.2–15.4) and blindness in 1.1% (95%CI: 0.5–1.6). The prevalence of VI ranged between 7.8% (95%CI: 6.0–9.5) in subjects aged 60–64 years and 40.0% (95%CI: 33.0–47.0) in participants over 80 years (p <.001). Multivariable logistic regression analysis showed that older age (OR = 1.07(per year)), lower education level (illiterate versus college: OR = 3.55), and lower economic status (middle versus rich: OR = 1.30 and poor versus rich; OR = 1.72) had a significant relationship with an increase in the prevalence of VI, and older age (OR = 1.14(Per year increase)) and diabetes (OR = 2.62) had a significant relationship with blindness. Refractive errors (63.1%) was the leading cause of VI followed by cataract (22.5%). However, cataract (48.3%) was the leading cause of blindness. Many older adults suffer from VI. Correction of refractive errors and cataract reduces a large percentage of VI. Age, education level, and economic status are other determinants of VI. [ABSTRACT FROM AUTHOR]

Evaluation of corneal higher-order aberrations can be used clinically to diagnose early cases of keratoconus as well as to classify the severity of keratoconus. To investigate the anterior and posterior corneal higher-order aberrations (HOAs) up to the sixth order and their ability to identify early keratoconus (KCN) as well as differentiate different severities of KCN using cross-validation analysis. This prospective cross-sectional comparative study was performed at a tertiary eye hospital in Tehran, Iran, in 2019. The study sample consisted of 95 eyes of 95 patients with KCN and 53 eyes of 53 normal individuals. The eyes with KCN were classified into three groups based on the Amsler–Krumeich classification system: group 1 (mild KCN), group 2 (moderate KCN), and group 3 (severe KCN). Corneal wavefront analysis was performed using Pentacam HR. Based on the magnitude of AUC, posterior vertical secondary coma (Z5−1) had an excellent discriminant ability (AUC: 0.91) and anterior vertical coma (Z3−1) and anterior vertical secondary coma (Z5−1) had a good discriminant ability (0.8 < AUC < 0.89) for differentiating eyes with mild KCN from normal eyes. The anterior and posterior primary spherical aberrations (Z4°) had an excellent ability (AUC > 0.9), and anterior secondary spherical aberration (Z6°) had a good ability (AUC: 0.83) for differentiating moderate from mild KCN. In the differentiation of severe from moderate KCN, anterior and posterior primary aspherical aberrations (Z4°) had a good AUC value (AUC > 0.8). Coma-like aberrations had a good discriminant ability between normal eyes and eyes with mild KCN. Spherical aberrations showed a good ability for differentiating between different stages of KCN. The cut-off values reported in this study can be used for early detection of KCN as well as classification of KCN severity. [ABSTRACT FROM AUTHOR]

Purpose: To determine the prevalence of astigmatism and its associated factors and examine astigmatism symmetry patterns in an elderly population. Study design: Population based cross-sectional study. Methods: The present population-based cross-sectional study was conducted on an elderly population above 60 years of age in Tehran, Iran in 2019. The sampling was done using the stratified multistage random cluster sampling method. All study participants underwent a complete optometric examination and slit-lamp biomicroscopy. Results: The prevalence of astigmatism higher than -0.50, -1.00, and -2.00 D was 83% (95% CI: 81 -84), 52 % (95% CI: 50 -54), and 19% (95% CI: 17-20), respectively. These prevalence was 79%(95% CI: 77-81), 46(95% CI: 44-49) and 14(95% CI: 13-16) in subjects without a history of ocular surgery, respectively. Based on cylinder power worse than -1.00 D, 10% (95% CI: 9-12), 20% (95% CI: 18-22), and 21% (95% CI:19-23) of study participants had with the rule, against the rule, and oblique astigmatism, respectively. According to the results of the multiple regression model, male gender, older age, low education level, pure posterior subcapsular cataract, pseudophakia, and myopia were independent factors associated with astigmatism. The prevalence of anisorule astigmatism was 57 % (95% CI: 56-59), the most common anisorule astigmatism was against the rule-oblique type with a prevalence of 36% (95% CI: 34-38). Conclusion: The prevalence of astigmatism was high in the elderly population of Tehran. More than half of the participants in this study had anisorule astigmatism, and against the rule-oblique combination was more prevalent than other types. A posterior subcapsular cataract, a history of cataract surgery, and myopia were the associated factors of astigmatism in this study. [ABSTRACT FROM AUTHOR]

Purpose: To determine the age and sex-standardized prevalence of corneal arcus and its associated factors in a geriatric population.Methods: This population-based cross-sectional study was conducted in 2019 in Tehran; the capital of Iran, using a multi-stage stratified random cluster sampling method. All participants underwent a detailed interview, blood pressure measurement, laboratory blood tests, and a complete ocular examination.Results: Three thousand three hundred ten of 3791 invitees participated in the study (response rate: 87.31%). The mean age of the participants was 69.35 ± 7.62 years (60-97 years) and 1912 (57.76%) were female. Overall, the age and sex-standardized prevalence (95% CI) of corneal arcus was 44.28% (41.21-47.39). Based on the multiple logistic regression, the odds of corneal arcus were higher in men than in women (OR: 1.51; 95% CI: 1.14-2.00); in the age group ≥ 80 years compared to the age group 60-64 years (OR: 2.44; 95% CI: 1.68-3.53), and in retired people compared to employed individuals (OR: 2.05; 95% CI: 1.31-3.21).Conclusion: The present study showed a high prevalence of corneal arcus in the geriatric population. Although various studies have reported a significant relationship between corneal arcus with blood lipid and glucose levels as well as blood pressure, these relationships were not found in the present study. [ABSTRACT FROM AUTHOR]

Purpose: To determine the distribution of blood glucose and prevalence of diabetes in people above 60 years living in Tehran and their relationship with some variables. Methods: In this cross-sectional population-based study, multistage cluster sampling was performed in the over 60-year-old population of Tehran. Blood samples were collected from all participants and the data of the history of diabetes and the use of blood glucose lowering agents or other drugs were collected using interviews. Results: Of 3791 selected subjects, 3310 participated in the study (response rate = 87.3%). The mean blood Sugar (BS) and hemoglobin A1c (HbA1c) of the patients was 118.11(95% CI: 115.34 -120.88) and 6.12(95% CI: 6.05–6.2) respectively. The prevalence of diabetes was 29.03%(95% CI: 27.12–30.94) in all subjects, 26.83%(95% CI: 24.58–29.07) in men, and 31.2%(95% CI: 28.24–34.16) in women. Odds of diabetes was significantly worse in women. systolic blood pressure, diasstolic blood pressure, height, weight, waist circumference, wrist circumference, hip circumference, neck circumference and body mass Index were significantly higher in diabetic after adjusting for the effect of sex and age. The odds of blindness was 2.69 (95% CI: 1.10–6.59) times higher in diabetic than in non-diabetics. Conclusions: On average, one in every three persons above 60 years of age was diabetic. Therefore, attention should be paid to this age group, especially women, due the higher prevalence of diabetes. All anthropometric measurements except height had a strong correlation with diabetes. Blindness was significantly more in diabetics. [ABSTRACT FROM AUTHOR]

Purpose: To determine the distribution of the corneal asphericity coefficient (Q value) and related factors in an Iranian geriatric population. Methods: This population‐based study was conducted in 2019 in Tehran, using stratified multistage random cluster sampling. The study population was ≥60 years of age. Participants underwent corneal imaging using a Pentacam HR. Mean keratometry, corneal astigmatism, central corneal thickness, anterior chamber depth and the overall anterior and posterior Q values (for 8 mm chord diameter) were recorded. Axial length measurements were performed using the IOL Master 500. Results: 2457 eyes of 2457 individuals were analysed. The mean age was 67.3 ± 5.82 years and 1479 (60.2%) were female. The mean Q value for the anterior corneal surface was −0.35 ± 0.17 (95% CI: −0.35 to −0.34). The anterior Q value showed a statistically significant inverse relationship with axial length and mean keratometry, and a significant direct association with anterior chamber depth and corneal astigmatism. The mean posterior Q value was −0.41 ± 0.15 (95% CI: −0.42 to −0.40). The posterior Q value had a significant direct relationship with age, anterior chamber depth, mean keratometry and corneal astigmatism. Conclusion: The corneal Q values in this geriatric Iranian population were more negative than the values reported in most previous studies. Corneal asphericity was greater affected by ocular biometry and corneal curvature than demographic factors and refractive status. [ABSTRACT FROM AUTHOR]

Aims/Purpose: To determine the corneal topographic indices of Scheimpflug camera in type 2 diabetic and non‐diabetic in elderly population of Tehran, Iran. Methods: A total of 1105 subjects were selected using random cluster sampling from Tehran, Iran and categorized into two groups including diabetics and non‐diabetics. The diabetic group had HbA1c levels ≥6.4% with no other systemic problems. The non‐diabetic participants had normal eye findings and no systemic diseases. The keratometry values, Q‐value, index of surface variance (ISV), index of vertical asymmetry (IVA), central keratoconus index (CKI), keratoconus index (KI), index of height asymmetry (IHA), index of height decentration (IHD), anterior average radius of curvature (ARC), posterior average radius of curvature (PRC), and pachymetric progression index (PPI) values were measured using the Pentacam AXL. Results: A total participants included 429 diabetic (38.46% male) and 676 non‐diabetic (38.76% male). Only PPIavg and PPImax were higher in the diabetics versus non‐diabetics (p = 0.019 and p = 0.010, respectively). The HbA1c level was 5.47 ± 0.34, 6.70 ± 0.17, and 8.72 ± 1.16 in the first, second, and third group, respectively. There was a significant difference in PPImax between the three groups (p = 0.036). There were significant differences only in IVA, CKI, PPIAvg, and PPImax between different stages of DR (p = 0.045, p = 0.005, p = 0.002, and p = 0.004, respectively). The diabetic subjects were divided into two groups based on the presence of DR. There was a significant difference in ISV, IVA, PPIavg, and PPImax between diabetic subjects with and without DR (p = 0.016, p = 0.022, p < 0.001, and p < 0.001, respectively). Conclusions: The results of this study showed that DM and DR change several topographic indices and the HbA1c level may affect PPImax. Therefore, special attention should be paid to these patients for different treatment strategies. [ABSTRACT FROM AUTHOR]

Aims/Purpose: To determine the association between dry eye with higher order aberrations (HOAs) and contrast sensitivity in 60 years old people and over. Methods: This population‐based study was conducted in Tehran, the capital of Iran, using stratified multistage random cluster sampling. All participants underwent complete ocular examination including measurement of uncorrected and best‐corrected visual acuity, refraction, slit‐lamp biomicroscopy. Zywave was used for measuring HOAs aberrations. Contrast sensitivity was measured with best correction visual acuity using the CVS1000 grating charts. Schirmer and tear break‐up time (TBUT) tests were used for evaluating dry eye in participants. Results: After applying exclusion criteria, the data of 397 individuals were analysed. A total of 415 people were invited, of whom 397 (62.8%) were females. The mean age of the participants was 68.32 ± 5.49 years. After adjusting with age and sex, in the multiple regression model that the TBUT test has a direct association with spherical aberration (p = 0.017) and an inverse association with coma, trefoil and the third, fourth and fifth order aberrations (p < 0.05). Schirmer test results also had a positive relationship with spherical aberration (p = 0.046) and an inverse relationship with coma, trefoil and the third, fourth and fifth order aberrations (p < 0.05). Contrast sensitivity had a significant association with Schirmer test result only in spatial frequency of 3CPD. Conclusions: The results of this study indicated the association between dry eyes and HOAs, and that the TBUT and Schirmer test results are of the most important factors in this relationship. Treating dry eye, can improve HOAs and quality of vision in elderly people. [ABSTRACT FROM AUTHOR]

Purpose: To determine the prevalence of anisometropia and its determinants in a population-based sample. Methods: In a cross-sectional population-based study, stratified cluster sampling was carried out from the population of Tehran. Respondents were transferred to a clinic for an interview and ophthalmic examinations including tests for visual acuity with and without correction, cycloplegic refraction, the slit lamp examination, fundoscopy, and lensometry. Anisometropia was defined as unequal spherical equivalent cycloplegic refractions in the two eyes. Results: Of 4565 participants, cycloplegic refraction was performed in both eyes of 3519 people. The mean age of the examinees was 31.5 ±± 18.0 (range, 5--86) years. The mean anisometropia was 0.34 diopter (D) (95% Confidence Interval (CI): 0.31--0.37). The prevalence rates of anisometropia more than 0.5, 1.0, 1.5 and 2.0 D were 18.5% (95% CI: 17.0--19.9), 6.7% (95% CI: 5.8--7.7), 3.8% (95% CI: 3.1--4.5) and 2.6% (95% CI: 2.1--3.1). The inter-gender difference in the prevalence of anisometropia ≥≥ 1.0D was not statistically significant ( P == 0.952). The prevalence of anisometropia increased after the age of 45 years. Overall, 15.7% of the examinees had anisomyopia and 4.7% had anisohypermetropia equal to or more than 1.0D. Anisometropia was more prevalent among patients with cataracts, amblyopia, and pseudophakia. The prevalence rates of spherical and cylindrical anisometropia in the studied sample were 8.0% and 7.1%, respectively. Conclusions: The prevalence of anisometropia in the population of Tehran is beyond negligible. It showed a significant increase with age. Results also indicate that myopic patients are more likely to have anisometropia. [ABSTRACT FROM AUTHOR]

Purpose: To determine the mean corneal power, astigmatism, and irregularity in a sample from the population of Tehran. Materials and methods: Four hundred and forty-two people residing in the first four municipality districts of Tehran were selected through a random stratified cluster sampling approach, 410 of which met the inclusion criteria and were enrolled in the study to have Orbscan II acquisitions between 9:00 am and 7:00 pm. The values obtained for keratometry, corneal astigmatism, and corneal irregularity were studied. Results: The mean keratometry reading was 44.39 diopter (D) [95% confidence interval (CI): 44.22-44.57]. Age, spherical equivalent and corneal diameter were significantly correlated with mean keratometry reading in the multivariate model. Mean corneal astigmatism was 0.98 D (95% CI: 0.89-1.06), also significantly correlated with spherical equivalent in the multivariate model. Mean corneal irregularity in the central 3 mm zone was 1.25 D (95% CI: 1.20-1.29); this was significantly correlated with age. Conclusions: In a sample of the Tehran population, we found higher values of mean corneal power, astigmatism, and irregularity compared to other reports. Considering the high prevalence of cases of suspect keratoconus in the studied population, it is important to pay more attention to corneal indices in keratorefractive surgery. [ABSTRACT FROM AUTHOR]

Purpose: To determine the age and sex-standardized prevalence and risk factors of anterior blepharitis in a geriatric population in "…".Methods: This population-based study was conducted on the elderly population (over 60 years of age) of Tehran, the capital of "…" in 2019. Examinations included visual acuity assessment, refraction, and complete slit lamp examination. After the diagnosis of anterior blepharitis, its type (staphylococcal vs. seborrheic) was also determined. Multiple logistic regression was used to determine the risk factors of the disease.Results: 3310 individuals participated in this study. The data of 3284 participants were available for this report. The mean age of the participants was 68.6 ± 24.5 years, and (57.8 %) were female. Age and sex-standardized prevalence of anterior blepharitis was 33.5 % (95 % CI: 30.6-36.5%) of which 96.5 % were bilateral. The prevalence of seborrheic and staphylococcal types was 22.4 % (95 % CI: 19.9-25.2%) and 11.3 % (95 % CI: 9.2-13.5%), respectively. According to the multiple logistic regression, the prevalence of anterior blepharitis was positively related to age over 80 years (P < 0.001) and male gender (P < 0.001), and inversely related to education level (P = 0.033). No significant relationship was found between anterior blepharitis and other variables including systemic hypertension, diabetes mellitus, hyperlipidemia, smoking, socioeconomic status, and history of the previous eye examination. Sex had the greatest effect on developing anterior blepharitis (standardized coefficient: 0.325).Conclusion: The results of this study showed a relatively high prevalence of anterior blepharitis in the elderly population which requires special attention of the health system to inform and control this disease through continuous training of the media and regional health centers. [ABSTRACT FROM AUTHOR]