The Increased Frequency of Type 1 Regulatory T (Tr1) Cells and the Altered Expression of Aryl Hydrocarbon Receptor (AHR) and Interferon Regulatory Factor-4 (IRF4) Genes in Type 1 Diabetes: A Case-Control Study.

Background and aim Type 1 diabetes is an autoimmune disorder characterized by the destruction of pancreatic beta cells, leading to insulin deficiency and hyperglycemia. Regulatory T cells (Tregs), particularly type 1 regulatory T (Tr1) cells, play a crucial role in modulating autoimmune responses. Therefore, this study aimed to evaluate the frequency of Tr1 cells and their association with aryl hydrocarbon receptor (AHR) and interferon regulatory factor-4 (IRF4) gene expression levels in type 1 diabetes mellitus (T1DM) compared to the healthy controls. Method A case-control study design was used. The case group included patients diagnosed with T1DM, while the control group consisted of healthy individuals, matched for age and sex. Blood samples were collected, and peripheral blood mononuclear cells (PBMCs) were isolated. Serum interleukin 10 (IL-10) and interleukin 21 (IL-21) levels were measured using enzyme-linked immunosorbent assay (ELISA). The gene expression of AHR and IRF4 was analyzed using quantitative real-time polymerase chain reaction (qPCR), and Tr1 cell populations were determined using flow cytometry. Data were summarized with mean and standard error of the mean (SEM) for quantitative variables. Independent sample t-test, chi-square test, and the Mann-Whitney U test were used to compare groups. Statistical analyses were performed using SPSS version 25 (IBM SPSS Statistics, Armonk, NY), with significance levels set at p < 0.05. Figures were created using GraphPad Prism (GraphPad Software, San Diego, CA). Results A total of 45 cases were enrolled in the study, with 30 T1DM patients and 15 healthy controls. The mean IL-10 concentration was significantly higher in the patients (10.4 ± 1.1 pg/mL) compared to the healthy controls (5.1 ± 0.7 pg/mL), with a p-value of 0.001. There was no significant difference in IL-21 levels between the patients (76.1 ± 9.0 pg/mL) and healthy controls (88.2 ± 17.5 pg/mL), indicated by a p-value of 0.480. AHR gene expression was significantly lower in patients, with a p-value of 0.037. Although IRF4 gene expression was higher in patients, the difference was not statistically significant (p = 0.449). Tr1 cell frequency was significantly higher in T1DM patients (1.45% of cluster of differentiation 4+ {CD4+} T cells) compared to the healthy controls (0.40% of CD4+ T cells), with a p-value of 0.045. Conclusions The study demonstrated that T1DM is associated with higher IL-10 levels, decreased AHR gene expression, and a higher frequency of Tr1 cells. Policymakers should focus on developing targeted immunomodulatory therapies to address these immunological abnormalities. Healthcare providers should prioritize monitoring cytokine levels and gene expression in T1DM patients to tailor treatment plans effectively. Further research is needed to explore the therapeutic potential of modulating Tr1 cells and their related pathways in T1DM management.

Optimal cut-points for body mass index, waist circumference and waist-to-hip ratio using the Framingham coronary heart disease risk score in an Arab population of the Middle East.

We aimed to determine the gender-specific optimal cut-points for body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) associated with risk of cardiovascular disease, using Framingham risk score and receiver-operating characteristic (ROC) analysis, among Omani Arabs. Nine percent of men, compared to 3% of women, had a 10-year total coronary heart disease (CHD) risk > or = 20%. In both genders, WHR was a better predictor of CHD (area under the ROC curve 0.771 for men and 0.802 for women), followed by WC (0.710 and 0.727) and BMI (0.601 and 0.639), respectively. For a 10-year CHD risk of > or = 20%, the optimal cut-points to assess adiposity in Omani men and women were > 22.6 and 22.9 kg/m2 for BMI, > 78.5 and 84.5 cm for WC, and > 0.96 and > 0.98 for WHR, respectively. To identify obesity among Omani Arabs, different cut-points for BMI, WC and WHR than the currently recommended ones are needed.

Visual disabilities among diabetics in Oman.

OBJECTIVE: The magnitude, determinants of visual impairment, bilateral blindness and low vision among diabetics in Oman were estimated as part of Oman Diabetic Eye Study 2002. This study presents the outcomes and additional risk of visual impairment in diabetics. METHODS: A cross-sectional study of 2,520 randomly selected diabetics was conducted in 2002 in 10 regions of Oman. The sample was represented by 5,564 diabetics referred for eye checks. Ophthalmologists noted the vision and ocular manifestations of diabetes. Physicians reported the systemic manifestations of diabetes. The magnitude of visual disabilities, bilateral blindness, legal blindness and low vision were estimated and compared to the rates in the population. RESULTS: The prevalence of visual impairment in diabetics was 28.4% (95% confidence interval [CI] 27.20-29.57). It was 34.6% (95% CI 32.93 to 36.32) in females and 21.2% (95% CI 19.59 to 36.32) in males. The prevalence increased in age. The prevalence of bilateral blindness (vision <0.05) was 0.7%, legal blindness 9.8% (vision <0.1) and low vision 27.7% (vision <0.5). CONCLUSION: The risk of visual impairment is 25 times more in diabetics than in the Omani population. Therefore, to prevent further increase of visual disabilities, the national health program should prioritize the eye care in diabetics and the predictors of visual disabilities should be further investigated.

Prevalence of the metabolic syndrome among Omani adults.

OBJECTIVE: To estimate the prevalence of the metabolic syndrome by age and sex in the Omani population as defined by the third report of the National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III [ATP III]) of North America. RESEARCH DESIGN AND METHODS: We analyzed data from a cross-sectional survey conducted in 2001 containing a probability random sample of 1,419 Omani adults aged > or =20 years living in the city of Nizwa. The metabolic syndrome, defined by the ATP III, was defined as having three or more of the following abnormalities: waist circumference >102 cm in men and >88 cm in women, serum triglycerides > or =150 mg/dl (1.69 mmol/l), HDL cholesterol <40 mg/dl (1.04 mmol/l) in men and <50 mg/dl (1.29 mmol/l) in women, systolic blood pressure > or =130 mmHg and/or diastolic > or =85 mmHg or on treatment for hypertension, and fasting serum glucose > or =110 mg/dl (6.1 mmol/l) or on treatment for diabetes. RESULTS: The age-adjusted prevalence of the metabolic syndrome was 21.0%. The crude prevalence was slightly lower (17.0%). The age-adjusted prevalence was 19.5% among men and 23.0% among women (P = 0.236). Low HDL cholesterol was the most common component (75.4%) of the metabolic syndrome among the study population followed by abdominal obesity (24.6%). Abdominal obesity was markedly higher in women (44.3%) than in men (4.7%). CONCLUSIONS: The prevalence of the metabolic syndrome in Oman is similar to that in developed countries. Future prevention and control strategies should not overlook the importance of noncommunicable disease risk factors in rapidly developing countries.

Health facilities for primary eye care in sultanate of oman: primary eye care study 2000.

OBJECTIVE: Endeavor to improve (i) the quality of Primary Eye Care with the aid of an Eye Health Care Programme and (ii) the resourcing Primary Eye Care in Ministry of Health Institutions in 2001. METHOD: In this descriptive study, staff were randomly selected from 84 health institutions and representing 136 primary health institutions to carry out quality assurance procedures. Ophthalmologists trained in this evaluation were field staff who evaluated the resource status, such as health staff, space for eye care delivery, instruments, materials for health education, referring cases (for continuous medical education of the primary health staff), drugs for eye care, etc., in each health institution. In addition to availability, the standards of eye care delivery were also estimated. RESULTS: The health institutes of Oman have adequate resources for Primary Eye Care. Additional requirement of ophthalmic loupes and medicaments would further improve Primary Eye Care in Oman. CONCLUSION: It is recommended that such a review of the health care programme and its resources and quality be periodically conducted as a part of a system of quality assurance in primary health care.

Prevalence of asthma symptoms in Omani schoolchildren.

OBJECTIVES: To determine the prevalence of asthma in Omani schoolchildren using the International Study of Asthma and Allergies in Children (ISAAC) protocols. METHOD: The ISAAC-written questionnaire was completed by a total of 7,067 Omani schoolchildren (3,893 children aged 6-7 years of which 56% were boys and 3,174 aged 13-14 years of which 51% were boys) from the 10 health regions in the country. RESULTS: The estimated mean national 12-month prevalence of any wheeze, night waking with wheeze, speech limiting wheeze and exercise wheeze were respectively 7.8%, 3.5%, 3.2% and 6.9% for the 6-7 year age group and 8.9%, 2.9%, 4.0% and 19.2% for the 13-14 year age group. Both age groups reported high prevalence of night cough (19.6% and 20.9% in the younger and the older children respectively). The prevalence of self-reported asthma diagnosis was higher in the older age group (20.7% vs. 10.5%, p<0.001). In the younger age group, the diagnosis of asthma was more common in boys (12.5% vs. 8.0%, p>0.001), but there was no significant difference between the two sexes in the older age group (22.0% of boys vs. 20.5% of girls). There was nearly three-fold difference in the prevalence of self-reported diagnosis of asthma between the regions with the highest and the lowest prevalence of asthma for both young and older children (from 5.3% and 9.5% in Musandam to 14.2% and 30.6% in South Sharqiya, respectively). CONCLUSION: The results of this first epidemiological survey of asthma in Oman indicate that asthma is common in Omani children and adolescents. Night cough is the most frequent symptom. There is also significant regional variation in prevalence of asthma symptoms and diagnosis within the country and this requires further investigation.

A relatively high prevalence and severity of asthma, allergic rhinitis and atopic eczema in schoolchildren in the Sultanate of Oman.

OBJECTIVES: Although asthma, allergic rhinitis and eczema are among the most common chronic diseases in children worldwide, there is very limited information about the burden of these conditions in Oman. The aim of this study was to determine the prevalence and severity of symptoms of asthma, allergic rhinitis and eczema in Omani schoolchildren using the International Study of Asthma and Allergies in Childhood (ISAAC) Phase I questionnaire. METHODS: An Arabic version of the ISAAC Phase I questionnaire was completed by parents of 3893 children aged 6-7 years and self-completed by 3174 children aged 13-14 years, randomly selected from a nationwide sample of public schools. RESULTS: The prevalence rates of reported diagnoses of asthma, allergic rhinitis and eczema were higher in older children (20.7%, 10.5% and 14.4% compared with 10.5%, 7.4% and 7.5%, respectively, in young children). In young children, 277 were current wheezers and of these 40.8% had sleep-disturbing wheeze at least once a week and 45.1% had speech-limiting wheeze during the past year. Similarly, 283 older children were current wheezers, and of these 30.0% had sleep-disturbing wheeze at least once a week and 37.5% had speech-limiting wheeze during the past year. Exercise-induced wheeze was higher in older children (19.2% vs 6.9%; P < 0.001). Allergic rhinitis and eczema were also associated with significant sleep disturbance and limitation of activity in both age groups. CONCLUSION: Allergic conditions in Omani schoolchildren are common and associated with significant morbidity. Further research is required to identify the local risk factors for allergy to allow better understanding and management of these conditions.