Five-year changes in macular thickness in the elderly population: A cohort study.

BACKGROUND: The aim of this study is to determine the 5-year changes in macular thickness and related factors. METHODS: Data were from the second (2014) and third (2019) phases of the Shahroud Eye Cohort Study. Examinations included measurement of uncorrected and best-corrected visual acuity, non-cycloplegic autorefraction, slit-lamp biomicroscopy, and funduscopy. Participants underwent Cirrus HD-OCT 4000 (Carl Zeiss Meditec, Dublin, CA). RESULTS: The 5-year changes (95% confidence interval) of central and overall macular thicknesses were - 3.48 ± 8.16 µ (-3.92, -3.03) and - 0.79 ± 4.06 µ (-1.03, -0.54), respectively. The median and IQR of 5-year changes in the central subfield thickness were -3 and 10, although they were 0 and 5 in the overall macular thickness, respectively. Multiple regression model showed the central macular thickness (CMT) decreased with a U-shape pattern with increasing age. The 5-year changes in CMT were significantly lower in females compared to males ß = -1.55; (-2.78, -0.32) and in smokers compared to non-smokers ß = -1.92; (-3.55, -0.28). Moreover, higher body mass index ß = -0.12; (-0.22, -0.02) and CMT at baseline ß = -0.08; (-0.10, -0.06) were significantly associated with lower CMT changes. The average 5-year changes in overall macular thickness showed a non-linear decrease with age and was significantly higher in females ß = 0.93; (0.4, 1.43). These changes were directly related to the anterior chamber depth ß = 0.87; (0.10, 1.64) in the baseline. CONCLUSIONS: The macular thickness decreased slightly after 5 years; however, this change is not clinically significant. Demographic factors such as age and sex and refractive errors were significantly related to macular thickness changes.

Effect of Transcranial Direct Current Stimulation on Craving, Cognitive Functions, and Serum Brain-Derived Neurotrophic Factor Level in Individuals on Maintenance Treatment for Opioid Use Disorder, A Randomized Sham-Controlled Trial.

OBJECTIVES: To investigate the effects of transcranial direct current stimulation (tDCS) on brain-derived neurotrophic factor (BDNF) levels, craving, and executive functions in individuals on maintenance treatment for opioid use. METHODS: We randomized 70 right-handed men aged 18-55 years into 2 groups: the intervention group and the sham group. The intervention was 10 sessions of 2 mA stimulation over 5 days. Each session in the sham group ended after 30 seconds. Craving was measured using the Desire for Drug Questionnaire (DDQ), Obsessive Compulsive Drug Use Scale (OCDUS), and visual analog scale (VAS). The measurements were taken before and after the intervention, as well as 2 months later. BDNF was measured before and after the intervention. Repeated-measures analysis of variance, the generalized estimating equation model, and independent t test were used for data analysis. RESULTS: The mean differences (95% confidence intervals) in pre and post craving scores in the intervention group were (12.71 [9.10 to 16.32], P = 0.167) for VAS, (1.54 [1.12 to 1.96], P = 0.012) for OCDUS, and (1.71 [1.27 to 2.15], P = 0.125) for DDQ. These measures in the control group were -0.44 (-1.19 to 0.30), 0.01 (-0.21 to 0.23), and 0.126 (-0.11 to 0.36), respectively. BDNF serum levels significantly increased after the intervention (difference, 0.84 [0.69 to 0.99], P < 0.001); however, this change was not significant in the generalized estimating equation model. The effect of tDCS on craving was significant in OCDUS, but not significant in VAS and DDQ. CONCLUSIONS: The tDCS reduces craving and improves executive functions in the short term. BDNF serum level was not associated with tDCS.

Reactogenicity within the first week after Sinopharm, Sputnik V, AZD1222, and COVIran Barekat vaccines: findings from the Iranian active vaccine surveillance system.

BACKGROUND: This study aimed to evaluate the reactogenicity effects of COVID-19 vaccines, used in Iran. METHODS: At least 1000 people were followed up with phone calls or self-report in a mobile application within 7 days after vaccination. Local and systemic reactogenicities were reported overall and by subgroups. RESULTS: The presence of one or more local and systemic adverse effects after the first dose of vaccines was 58.9% [(95% Confidence Intervals): 57.5-60.3)] and 60.5% (59.1-61.9), respectively. These rates were reduced to 53.8% (51.2-55.0) and 50.8% (48.8-52.7) for the second dose. The most common local adverse effect reported for all vaccines was pain in the injection site. During the first week after the first dose of vaccines, the frequency of the pain for Sinopharm, AZD1222, Sputnik V, and Barekat was 35.5%, 86.0%, 77.6%, and 30.9%, respectively. The same rates after the second dose were 27.3%, 66.5%, 63.9%, and 49.0%. The most common systemic adverse effect was fatigue. In the first dose, it was 30.3% for Sinopharm, 67.4% for AZD1222, 47.6% for Sputnik V, and 17.1% for Barekat. These rates were reduced to 24.6%, 37.1%, 36.5%, and 19.5%, in the second dose of vaccines. AZD1222 had the highest local and systemic adverse effects rates. The odds ratio of local adverse effects of the AZD1222 vaccine compared to the Sinopharm vaccine were 8.73 (95% CI 6.93-10.99) in the first dose and 4.14 (95% CI 3.32-5.17) in the second dose. Barekat and Sinopharm had the lowest frequency of local and systemic adverse effects. Compared to Sinopharm, systemic adverse effects were lower after the first dose of Barekat (OR = 0.56; 95% CI 0.46-0.67). Reactogenicity events were higher in women and younger people. Prior COVID-19 infection increased the odds of adverse effects only after the first dose of vaccines. CONCLUSIONS: Pain and fatigue were the most common reactogenicities of COVID-19 vaccination. Reactogenicities were less common after the second dose of the vaccines. The adverse effects of AZD1222 were greater than those of other vaccines.

Prevalence of uncontrolled hypertension and its associated factors in 50-74 years old Iranian adults: a population-based study.

BACKGROUND: By the lengthening of life span, the incidence of chronic diseases such as hypertension and uncontrolled hypertension has increased. This study aims to determine the prevalence of uncontrolled hypertension and its related factors in the age group of 50-74 years in Shahroud, northeast Iran. METHODS: The data of the third phase of the Shahroud Eye Cohort Study were used in this study. This phase of the cohort study included 4394 participants aged 50 to 74 years from the previous phases. In addition to ophthalmological and optometric examinations, demographic characteristics, blood biochemistry tests, and blood pressure measurements were performed in this phase. Individuals with a blood pressure ≥ 140/90 mm/Hg (being treated or not treated with antihypertensive medicines) were defined as uncontrolled hypertension. In patients with diabetes and chronic kidney disease, blood pressure equal to or higher than 130/80 mm/Hg was considered uncontrolled hypertension. Descriptive statistics and multiple logistic regression were used to analyze the data. FINDINGS: Overall, the prevalence of uncontrolled hypertension out of all the participants was 61.7% (95% CI: 60.3-63.2). Multiple regression results showed that the male gender (OR: 2.1, 95% CI: 1.5-2.9), patients with diabetes (OR:3.2, 95% CI: 2.4-4.3), and patients with chronic kidney disease (CKD) (OR: 3.2, 95% CI: 2.5-4.1) increased the risk of uncontrolled hypertension while in patients with cardiovascular disease (OR: 0.6, 95% CI: 0.4-0.8) and polypharmacy (OR: 0.2, 95% CI: 0.1-0.2) reduced the risk of uncontrolled hypertension. CONCLUSION: The present study showed that uncontrolled hypertension has a high prevalence, and factors such as male gender, diabetes, and CKD are associated with this disorder. So, it is recommended to take the necessary measures to formulate and implement immediate actions to prevent or control hypertension.

A prospective cohort study protocol: monitoring and surveillance of adverse events following heterologous booster doses of Oxford AstraZeneca COVID-19 vaccine in previous recipients of two doses of Sinopharm or Sputnik V vaccines in Iran.

BACKGROUND: Regarding the paucity of evidence on the side effects of the booster dose of Oxford AstraZeneca vaccine in vaccinated people with Sinopharm or Sputnik V, we aimed to set up a cohort event monitoring (CEM) study to capture adverse events occurring in individuals who will receive the booster doses of AstraZeneca (either the first or second booster dose) following being vaccinated with Sinopharm or sputnik V vaccines in Iran. METHODS: The present study is an active COVID-19 vaccine safety surveillance through an observational prospective cohort study that will be conducted in vaccination centers in Iran. The study will be conducted in twelve provinces of Iran. Study sites are vaccination centers where the AstraZeneca vaccine is administered to the cohort population. The study population includes all individuals who have received two doses of Sinopharm or Sputnik V vaccines and either the first or second booster dose of AstraZeneca according to the national guidelines for immunization in Iran in 2023. We are planning to include 30,000 eligible people in this study. Each individual will be followed up for 13 weeks after either the first or second booster dose of the AstraZeneca vaccine. Furthermore, convenience sampling is used to include participants in the present study. Participation in the study will be strictly voluntary. DISCUSSION: With the planned study we will provide a valid epidemiological evidence to improve the understanding of the safety of the booster dose of the AstraZeneca and to better evaluate the effectiveness of public health interventions. This could help policy makers in managing the COVID-19 pandemic according to scientific evidence.

Three-year change in corneal asphericity in children at the age of emmetropisation.

PURPOSE: To determine the 3-year changes in anterior and posterior values of corneal asphericity (Q) in 6- to 12-year-old children. METHODS: The first and second phases of the study were conducted in 2015 and 2018, respectively. The target population in the first phase was 6- to 12-year-old students in Shahroud, Iran. Multistage cluster sampling was performed on urban students. Additionally, all rural students in Shahroud county were invited to participate. Corneal imaging and ocular biometry were performed using the Pentacam-HR and Allegro Biograph, respectively. RESULTS: A total of 4961 right eyes were analysed in this report. The mean (95% confidence interval) anterior and posterior Q values for an 8-mm chord diameter were -0.38 ± 0.11 (-0.39 to -0.38) and -0.32 ± 0.12 (-0.33 to -0.32) in the first phase of the study, respectively. The mean 3-year changes in anterior and posterior Q values were 0.00 ± 0.08 (95% CI: 0.00-0.00) and -0.01 ± 0.06 (95% CI: -0.01 to -0.01), respectively. Based on a multiple regression model, advancing age (ß = -0.002; [-0.003 to -0.001]), 3-year increase in mean keratometry (ß = -0.04; [-0.06 to -0.02]), central corneal thickness (ß = -0.001; [-0.001 to -0.000]), lens thickness (-0.05; [-0.11 to -0.003]) and anterior chamber depth (-0.09; [-0.15 to -0.03]) showed a statistically significant association with increased anterior Q prolation. Increased axial length was associated with a decrease in Q (ß = 0.02; [0.004 to 0.03]). In addition, female gender (ß = -0.004; [-0.007 to -0.001]) was significantly associated with a more prolate posterior Q value, while rural residence (ß = 0.005; [0.002 to 0.009]) was significantly associated with a more oblate posterior Q value. CONCLUSION: Three-year changes in anterior and posterior Q values were very small. The cornea tends to become more prolate with increasing age.

Economic inequalities in decayed, missing, and filled first permanent molars among 8-12 years old Iranian schoolchildren.

BACKGROUND: First permanent molars (FPM) play an important role in the masticatory function and oral health. This study aimed to assess the economic inequalities of FPM health indices among schoolchildren in the northeast of Iran. METHODS: A total of 4051 children aged 8-12 years old were included in the analyses of this cross-sectional study in 2015. Economic status was measured using the principal component analysis on home assets. Concentration index (C) was used to measure economic inequality in FPM health indices, and its contributing factors determined by Wagstaff decomposition technique. RESULTS: The prevalence of having decayed, missing, and filled FPMs among children was 40.9% (95% CI: 38.8-43.0), 1.2% (95% CI: 0.8-1.6%), and 7.8% (95% CI: 6.7-8.9%), respectively. Missing FPM was generally more concentrated among low-economic children (C=-0.158), whereas, filled FPM was more concentrated on high-economic children (C = 0.223). Economic status, mother education, having a housekeeper mother, and overweight/obesity, contributed to the measured inequality in missing FPM by 98.7%, 97.5%, 64.4%, and 11.2%, respectively. Furthermore, 88.9%, 24.1%, 14.5%, and 13.2% of filled FPM inequality was attributable to children's economic status, father education, residence in rural areas, and age, respectively. CONCLUSION: There is a significant economic inequality in both missing and filled FPM. This inequality can be attributed to the economic status of individuals. To reduce FPM extraction, it is important to target low-income and rural children and provide them with FPM restoration services. Additionally, it is necessary to provide training to less-educated parents and housekeeper mothers to address the observed inequalities.

Isolated systolic hypertension and its associated risk factors in Iranian middle age and older population: a population-based study.

BACKGROUND: Isolated systolic hypertension (ISH), is the most common form of hypertension in older adults. However, the ISH prevalence is not well known in many developing countries such as Iran. This study was conducted to determine the ISH prevalence and its related risk factors in an Iranian population. METHODS: Data were obtained from the second phase of the Shahroud eye cohort study (ShECS) in 2014. ShECS is a longitudinal population-based study which the first phase had been conducted in 2009 using the stratified multistage cluster sampling design on 5190 people aged 40 to 70 years. The ISH prevalence was determined based on the eighth Joint National Commission guidelines for different demographic variables. The associated risk factors were estimated by multiple logistic regression and a two-tailed p-value less than 0.05 was considered significant. RESULTS: The ISH prevalence was 15.89% (95% CI: 14.88-16.96). It was 15.68% (14.12-17.39) and 15.87% (14.54-17.29) for men and women, respectively. The prevalence of ISH increased significantly with increasing age. The 65-70 compared to 45-69 year age group (OR = 4.21), body mass index (OR = 1.03), diabetes (OR = 1.64), retirement, compared to practitioner job (OR = 1.53), and waist to hip ratio (WHR) (OR = 9.81) were significantly associated with ISH prevalence. CONCLUSIONS: ISH is highly prevalent among the older adult population in Iran. Given the risk of cardiovascular disease associated with ISH, it is recommended to conduct education and public health interventions to improve the detection, prevention, and treatment of ISH.

Socioeconomic inequality in depression and anxiety and its determinants in Iranian older adults.

BACKGROUND: Older adults with lower socioeconomic status are more vulnerable to stressful life events and at increased risk of common mental health disorders like anxiety and depression. This study investigates the socioeconomic inequality in depressive symptoms and anxiety. METHODS: The data were from 7462 participants of the Neyshabur longitudinal study of ageing registered during 2016-2018. The outcome variables were anxiety and depressive symptoms. Anxiety was defined by the "Hospital Anxiety and Depression scale Questionnaire", and depressive symptoms was defined and measured by the "short-term form of the Epidemiological Center Questionnaire." The socioeconomic status was defined using principal component analysis of home assets. The Concentration Index (C) was used to measure socioeconomic inequality in anxiety and depressive symptoms. Concentration index was decomposed to its determinants to determine the role of the independent variables on inequality. RESULTS: The prevalence of depressive symptoms and anxiety was 12.2% (95% CI: 11.4, 12.9) and 7.0% (95% CI: 6.4, 7.5), respectively. Moreover, the C for anxiety was -0.195 (95% CI: -0.254, -0.136) and for depressive symptoms was -0.206 (95% CI: -0.252, -0.159), which indicate a considerable inequality in favor of high socioeconomic group for anxiety and depressive symptoms. Decomposition of the concentration Index showed that education, unemployment and male sex were the most important positive contributors to the observed inequality in anxiety and depressive symptoms, while age and number of grandchildren were main negative contributors of this inequality. CONCLUSION: Low socioeconomic groups were more affected by anxiety and depressive symptoms. Any intervention for alleviation of inequality in anxiety and depression should be focus on education and employment of people, especially in younger elderly.

MACULAR THICKNESS BY USING SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY IN CHILDREN AND ADOLESCENTS.

PURPOSE: To determine the distribution of macular and cube thickness and their normal range in the students aged 9 years to 15 years and to investigate their associated demographic and biometric factors. METHODS: This study was based on the data of the second phase of the Shahroud School Children Eye Cohort Study, conducted in 2018. After measurements of visual acuity, biometry, and subjective and cycloplegic refraction, retinal examination was performed using the Zeiss Cirrus HD 4000 optical coherence tomography. RESULTS: The data of 5,043 right eyes were analyzed after applying the exclusion criteria. The central macular thickness was 239 ± 19.35 µ m. The mean cube volume and cube thickness were 9.94 ± 0.44 and 278 ± 12.20, respectively. According to multiple linear regression analysis, the central macular thickness was significantly lower in girls (coefficient [ß]: -9.18; P < 0.001) and rural students (ß: 3.86; P < 0.001) and had a direct association with axial length (ß: 5.19; P < 0.001), lens thickness (ß: 5.33; P = 0.003), and mean keratometry (ß: 2.41; P < 0.001). The cube volume was lower in girls (ß: -0.13; P < 0.001) and higher in rural students (ß: 0.05; P < 0.001). CONCLUSION: Macular thickness was slightly higher in Iranian children. Sex, living place, axial length, lens thickness, and mean keratometry were the main associated factors with macular thickness.

Prevalence of ocular trauma in 6-12-year-old children living in Shahroud, Iran.

AIM: To determine the prevalence of ocular trauma in Iranian children aged 6-12 years. METHODS: This population-based cross-sectional study, comprised the first phase of the Shahroud Schoolchildren Eye Cohort Study on primary school children using cluster sampling in urban areas and census in rural areas. The students underwent the measurement of uncorrected and corrected visual acuity as well as non-cycloplegic, cycloplegic, and subjective refraction. The history of trauma, hospitalization, and surgery due to trauma was collected from parents using a questionnaire. RESULTS: The data of the trauma history was recorded for 5267 out of 5620 students. The mean age of the students was 9.7 ± 1.7 years (range: 6-12 years), 53.7% of them were boys, and 79.3% were from urban areas. A positive history of ocular trauma was found in 285 participants, and the lifetime prevalence of ocular injury (95% CI) was 5.2% (4.6-5.9). Blunt trauma was the most common ocular injury with a prevalence of 66.2%. There was a significant positive assocation between ocular trauma and living in rural areas (OR: 1.49, p: 0.012), older age (OR: 1.17, p < 0.001), and male sex (OR: 1.62, p: 0.002). Furthermore, 9.3% and 4.7% of the traumas required hospitalization and surgical intervention, respectively. CONCLUSION: This study found a marked prevalence of ocular trauma compared to previous studies. Male sex, older age, and living in rural areas were associated with ocular trauma, which could be due to differences in lifestyle preference, outdoor exposure, and dangerous situations. Educational programs and safety instructions should be encouraged.

Visual functions and disability in Iranian adults: a population-based study.

BACKGROUND: Vision-related quality of life is related to severity of visual impairments and show the impact of eye diseases on daily activities. This study aims to assess visual functions and disability and its association with age, gender, education, marital status, and economic status in adults aged 45-69 years. METHODS: Data in this population-based study were from the second phase of the Shahroud eye cohort study and collected by using a Short-Form Visual Functioning Scale. The scores of visual function and disability were calculated based on Rasch-transformed scores of the National Eye Institute visual functioning questionnaire, where a more negative score indicates a better situation. Multiple linear regression was used to investigate the factors associated with visual functions. RESULTS: Among 4737 participants the visual function data for 4715 people were analyzed. The visual function of 75.3, 17.1 and 7.5% of participants were "ideal and good", "moderate", and "bad and very bad", respectively, while 0.06% were unable for vision. The running mean of the visual function was calculated to be - 3.95 ± 0.02. The visual performance was worse in females than the males (ß = 0.14, p = 0.005). Visual function improved with increasing levels of education (ß = - 1.06, p < 0.001). It was worse in low-economic (ß = 0.016, p = 0.005) and moderate-economic (ß = 0.28, p < 0.001) participants than high-economic ones. CONCLUSION: The visual function of Iranian adults aged 45-69 years was moderate. The male gender, higher education and the higher economic status had a better visual function.

Long-Term Persistence of Anti-SARS-COV-2 IgG Antibodies.

Antibodies against severe acute respiratory syndrome coronavirus-2 (Anti-SARS-COV-2) can be detected in patients with COVID-19 in 7 to 10 days post onset of symptoms (POS). However, there is no firm evidence of the long-term persistence of these antibodies in recovered COVID-19 patients. Therefore, this study aimed to evaluate the stability of anti-SARS-COV-2 IgG in recovered COVID-19 patients in a 15-month follow-up testing. Thirty hospitalized patients with real-time PCR-confirmed SARS-COV-2 infections were included in the study and five serum samples (1st, 2nd, 3rd, 4th, and 5th) were collected from each participant. The serum levels of N and S specific anti-SARS-COV-2 IgG and IgM antibodies were evaluated by the immunoassay technique at the same time. To determine the correlation between levels of anti-SARS-CoV-2 IgG/IgM with severity of disease, neutrophil-to-lymphocyte ratio (NLR %), and the serum levels of C-reactive protein were evaluated using an automated analyzer and turbidimetry assays, respectively. The mean serum level of anti-SARS-CoV-2 IgG antibody was at the highest level up to 90 days and then decreased significantly 1 year POS (P < 0.0001). However, it was still detectable in a 15-month follow-up testing. There were no significant differences in the mean levels of IgG antibody in patients with mild, moderate, and severe diseases. The results from this study suggest that the titer of anti-SARS-COV-2 IgG antibody is detectable at high levels up to 3 months and then decreases over time. However, these antibodies can be reliably detected in up to 15 months, and they may persist for a long time.

Study protocol: cohort event monitoring for safety signal detection after vaccination with COVID-19 vaccines in Iran.

BACKGROUND: New vaccines that are initially approved in clinical trials are not completely free of risks. Systematic vaccine safety surveillance is required for ensuring safety of vaccines. This study aimed to provide a protocol for safety monitoring of COVID-19 vaccines, including Sputnik V, Sinopharm (BBIBP-CorV), COVIran Barekat, and AZD1222. METHODS: This is a prospective cohort study in accordance with a template provided by the World Health Organization. The target population includes citizens of seven cities in Iran who have received one of the available COVID-19 vaccines according to the national instruction on vaccination. The participants are followed for three months after they receive the second dose of the vaccine. For each type of vaccine, 30,000 people will be enrolled in the study of whom the first 1,000 participants are in the reactogenicity subgroup. The reactogenicity outcomes will be followed seven days after vaccination. Any hospitalization, COVID-19 disease, or other minor outcomes will be investigated in weekly follow-ups. The data are gathered through self-reporting of participants in a mobile application or phone calls to them. The study outcomes may be investigated for the third and fourth doses of vaccines. Other long-term outcomes may also be investigated after the expansion of the follow-up period. We have planned to complete data collection for the current objectives by the end 2022. DISCUSSION: The results of this study will be published in different articles. A live dashboard is also available for managers and policymakers. All data will be available on reasonable requests from the corresponding author.The use of the good and comprehensive guidelines provided by WHO, along with the accurate implementation of the protocol and continuous monitoring of the staff performance are the main strengths of this study which may be very useful for policymaking about COVID-19 vaccination.

COVID-19 re-infection in Shahroud, Iran: a follow-up study.

Although many people became infected and recovered during the COVID-19 epidemic, the immunity duration and re-infection in recovered patients have recently attracted many researchers. The aim of this study was to evaluate the recurrence of the infection in recovered individuals over a 9-month period after the onset of the COVID-19 epidemic. In this study, data related to COVID-19 patients in Shahroud city were collected using the electronic system for registering suspicious patients and also by checking patients' hospital records. In this study, from 20 March 2020 to 20 November 2020 (9 months), a total of 8734 suspected patients with respiratory symptoms were observed and followed up. RT-PCR was positive for 4039 patients. During this period, out of the total number of positive cases of COVID-19, 10 cases became re-infected after complete recovery. The risk of re-infection was 2.5 per thousand (0.95 CI 1.2-4.5). The mean time interval between the first infection and re-infection was 134.4 ± 64.5 days (range 41-234 days). The risk of re-infection between male and females was not statistically different (1.98 per 1000 women and 2.96 per 1000 men). Exposure to COVID-19 may not establish long-term protective immunity to all patients and may predispose them to re-infection. This fact can be reminded that the use of masks, social distancing and other preventive measures are very important in recovered patients and should be emphasised especially in health care personnel who are more exposed to the virus.

Salt intake and blood pressure in Iranian children and adolescents: a population-based study.

BACKGROUND: Previous studies have reported a high prevalence of hypertension in Iranian students, especially in rural areas. The aim of this study was to investigate the daily intake of salt in students and its association with high blood pressure. METHODS: A random sub-sample was selected from the participants of the second phase of Shahroud schoolchildren eye cohort study and then a random urine sample was tested for sodium, potassium and creatinine. Urine electrolyte esexcretion and daily salt intake were calculated by Tanaka et al.'s formula. RESULTS: Among 1455 participants (including 230 participants from rural area and 472 girls), the mean age was 12.9 ± 1.7 year and the mean daily salt intake was 9.7 ± 2.6 g (95% CI 9.5-9.8). The mean salt consumption in rural areas [10.8 (95% CI 10.4-11.2)] was higher than urban areas [9.4 (95% CI 9.3-9.6)], in people with hypertension [10.8 (95% CI 10.3-11.3)] was more than people with normal blood pressure [9.4 (95% CI 9.3-9.6)], and in boys [9.8 (95% CI 9.7-10.0)] was more than girls [9.3 (95% CI 9.1-9.6)]. Higher age, BMI z-score, male sex and rural life, were associated with increased daily salt intake. Increased salt intake was associated with increased systolic and diastolic blood pressure. CONCLUSION: Daily salt intake in Iranian adolescents was about 2 times the recommended amount of the World Health Organization, was higher in rural areas and was associated with blood pressure. Reducing salt intake should be considered as an important intervention, especially in rural areas.

Addressing Individual Ophthalmic Health in Public Health Research.

In pediatric cohort studies, disclosing findings and providing treatment counseling to parents, legal guardians, or other authorized representatives is an ethical imperative. Keratoconus (KC) is a corneal degenerative disease that can progress to severe vision impairment and need for corneal transplantation. This report concerns the disclosure of results to the parents of children who were diagnosed with KC in the Shahroud Schoolchildren Eye Cohort Study and received essential treatment in a timely manner.

The Effect of Cyclopentolate on Ocular Biometric Components.

SIGNIFICANCE: It is apparent that a variety of biometric changes are caused by different types of cycloplegic eye drops. However, these effects are inconsistent and have not been reported in different refractive groups. PURPOSE: The purpose of this study was to determine the effect of cyclopentolate 1% on ocular biometric components in different types of refractive errors in children. METHODS: This cross-sectional study was conducted on 226 eyes of 113 schoolchildren in Shahroud, northeast Iran, with a mean ± standard deviation age of 9.20 ± 1.65 years. All participants had noncycloplegic and cycloplegic objective refraction using an autorefractometer. Cycloplegia was induced using cyclopentolate 1% eye drops. Biometric measurements were made with Allegro Biograph (WaveLight AG, Erlangen, Germany) before and after administering cycloplegic drops. Mixed-effect model regression was used to analyze the data. RESULTS: After cycloplegia, the vitreous chamber depth (VCD) (-0.043; 95% confidence interval [CI], -0.067 to -0.019 mm), lens thickness (-0.146; 95% CI, -0.175 to -0.117 mm), axial length (-0.009; 95% CI, -0.012 to -0.006 mm), and lens power (-0.335; 95% CI, -0.463 to -0.208 D) decreased significantly, whereas the anterior chamber depth (ACD) (0.183; 95% CI, 0.164 to 0.202 mm), anterior segment length (0.036; 95% CI, 0.014 to 0.058) mm), lens central point (0.109; 95% CI, 0.094 to 0.124 mm), and pupil diameter (1.599; 95% CI, 1.482 to 1.716 mm) increased (P value for all tests, <.001). For changes in VCD and ACD, a significant interaction was observed between different types of refractive errors and cycloplegia, such that the adjusted mean change for ACD was significantly lower and for VCD was significantly higher in hyperopes compared with emmetropes. Lens center moves backward in myopes (0.17 mm) and stays the same in hyperopes under cycloplegia. CONCLUSIONS: According to the findings of this study, cycloplegia reduces the thickness of the crystalline lens and subsequently causes an increase in the ACD. Cycloplegia-related ocular biometric changes were different by type of refractive error.

Distribution of Keratoconus Indices in Normal Children 6 to 12 Years of Age.

OBJECTIVES: To determine the distribution of keratoconus indices in normal children 6 to 12 years of age. METHODS: This cross-sectional study was conducted in children living in urban and rural areas of Shahroud, northeast Iran in 2015. After careful optometric examinations, the Pentacam was used for corneal imaging and measurement of keratoconus indices. RESULTS: Of 5,620 students who participated in the study, the data of the right eye of 4,947 children were analyzed after applying the exclusion criteria. The mean age of all children was 9.23±1.71 years (range: 6-12 years). The mean and 95% confidence intervals (in the parentheses) of index of surface variance (ISV), index of vertical asymmetry, keratoconus index (KI), central keratoconus index (CKI), index of height asymmetry, index of height decentration (IHD), and average pachymetric progression index (PPIAve) was 17.770 (17.610-17.930), 0.137 (0.135-0.139), 1.022 (1.022-1.023), 1.010 (1.010-1.010), 3.299 (3.230-3.368), 0.007 (0.007-0.008), and 0.948 (0.943-0.952), respectively. The results of multilevel mixed-effects linear regression analysis showed that ISV, KI, CKI, IHD, and PPIAve were significantly higher in girls. Index of surface variance and CKI were higher in urban students, and PPIAve was higher in rural students. Except for PPIAve, which was increased with increasing age, the mean values of other keratoconus indices were significantly lower in 12-year-old students compared with 6-year-old ones. CONCLUSION: The results provide valuable information about normal distribution of keratoconus indices in children aged 6 to 12 years. These findings can be used in future research and detection of abnormal cases in the clinical setting.

Distribution of Different Corneal Topography Patterns in Iranian Schoolchildren: The Shahroud Schoolchildren Eye Cohort Study.

OBJECTIVES: To determine the distribution of corneal topography patterns (CTPs) in children aged 6 to 12 years and its association with the central corneal thickness (CCT), axial length (AL), mean corneal power (MCP), and corneal astigmatism (CA). METHODS: In this population-based study, 5,620 children selected through random stratified cluster sampling were examined. After applying the inclusion criteria, 4,655 right eyes were analyzed. The Pentacam was used to determine the CTP and measure CA and MCP, and the BioGraph was used to measure the AL. Corneal topography patterns were classified based on the 10 patterns proposed by Rabinowitz et al. RESULTS:: The most common pattern in the right eye was the oval pattern [32.7%, 95% confidence interval (CI): 30.9-34.5] followed by asymmetric bowtie with superior steepening (AB-SS) (14.5%, 95% CI: 13.3-15.7), whereas the rarest patterns were AB with skewed radial axis (AB-SRAX) (0.1%, 95% CI: 0.0-0.2) and irregular pattern (0.2%, 95% CI: 0.1-0.4). The similarity between the two eyes was 23.2% (95% CI: 20.9-25.7). The mean CCT was significantly higher in AB-SS than inferior steepening (IS) (P=0.023), symmetric bowtie with SRAX (SB-SRAX) (P=0.030), and AB with IS (AB-IS) (P=0.015). Corneal astigmatism was higher in SB-SRAX compared with round and oval patterns (P value for both <0.001). The AL was greater, and the MCP was lower in the oval versus the SB-SRAX pattern (P value for both <0.001). CONCLUSION: The distribution of CTP was different in children and adults, and the oval and AB-SS patterns were the most common CTPs in the current study.