The prevalence of atopic dermatitis among children aged between 6 months and 12 years attending primary health care clinics in Qatar 2018-2019

Background: The prevalence of atopic dermatitis among children appears to have increased dramatically over the past decades. Such rapid increase in prevalence cannot be explained fully. Genetic factors, microbiomes (especially staphylococcus aureus infection), food allergy and environmental factors might play a role in such an increment. This study aimed to report the prevalence of atopic dermatitis among children aged 6 months to 12 years attending primary health care centers in Qatar during the year 2018 and 2019.Methods: Cross-sectional retrospective data analysis of all registered cases having at least one visit in any of the 28 health centers dermatology clinics operated by PHCC with a verified diagnosis of atopic dermatitisResults: Out of 4521 patients dermatology clinic visit, 1359 had atopic dermatitis during the period of 2018 and 2019, and the prevalence rate is 30.06 (95% CI 28.72-31.42). In this 1359 atopic dermatitis cases, mean age of patients was 5.09±3.53 years and ranged from 6 months to 12 years. In this 18.9% was <1 years, 41.43% was 1-5 years, 19.35% was 5-8 years and 21.04% was 8-12 years. Prevalence of AD is high in boys 31.42% than girls 28.81% and is high in Qatari population 34.4% than the non-Qatari population 28.7%. The most frequently prescribed medication group was topical emollients (89.8%) followed by antihistamine (81.24%) and antibiotics (56.73%). Steroids were prescribed only for 7.3% of cases.Conclusions: In this study the prevalence of atopic dermatitis was remarkably very high in young children in Qatar. Further prospective research and more efforts are needed to develop a standard treatment regimen for allergic diseases in Qatar

Association between Multimorbidity and COVID-19 Mortality in Qatar: A Cross-Sectional Study

This study assessed the association between multimorbidity and mortality from COVID-19 in the Middle East and North Africa region, where such data are scarce. We conducted a cross-sectional study using data of all cases with COVID-19 reported to the Ministry of Public Health of Qatar from March to September 2020. Data on pre-existing comorbidities were collected using a questionnaire and multimorbidity was defined as having at least two comorbidities. Proportions of deaths were compared by comorbidity and multimorbidity status and multivariable logistic regression analyses were carried out. A total of 92,426 participants with a mean age of 37.0 years (SD 11.0) were included. Mortality due to COVID-19 was associated with gastrointestinal diseases (aOR 3.1, 95% CI 1.16–8.30), respiratory diseases (aOR 2.9, 95% CI 1.57–5.26), neurological diseases (aOR 2.6, 95% CI 1.19–5.54), diabetes (aOR 1.8, 95% CI 1.24–2.61), and CVD (aOR 1.5, 95% CI 1.03–2.22). COVID-19 mortality was strongly associated with increasing multimorbidity; one comorbidity (aOR 2.0, 95% CI 1.28–3.12), two comorbidities (aOR 2.8, 95% CI 1.79–4.38), three comorbidities (aOR 6.0, 95% 3.34–10.86) and four or more comorbidities (aOR 4.15, 95% 1.3–12.88). This study demonstrates a strong association between COVID-19 mortality and multimorbidity in Qatar

Dynamics of Anti-S IgG Antibodies Titers after the Second Dose of COVID-19 Vaccines in the Manual and Craft Worker Population of Qatar

There is limited seroepidemiological evidence on the magnitude and long-term durability of antibody titers of mRNA and non-mRNA vaccines in the Qatari population. This study was conducted to generate evidence on long-term anti-S IgG antibody titers and their dynamics in individuals who have completed a primary COVID-19 vaccination schedule. A total of 300 male participants who received any of the following vaccines BNT162b2/Comirnaty, mRNA-1273, ChAdOx1-S/Covishield, COVID-19 Vaccine Janssen/Johnson, or BBIBP-CorV or Covaxin were enrolled in our study. All sera samples were tested by chemiluminescent microparticle immunoassay (CMIA) for the quantitative determination of IgG antibodies to SARS-CoV-2, receptor-binding domain (RBD) of the S1 subunit of the spike protein of SARS-CoV-2. Antibodies against SARS-CoV-2 nucleocapsid (SARS-CoV-2 N-protein IgG) were also determined. Kaplan–Meier survival curves were used to compare the time from the last dose of the primary vaccination schedule to the time by which anti-S IgG antibody titers fell into the lowest quartile (range of values collected) for the mRNA and non-mRNA vaccines. Participants vaccinated with mRNA vaccines had higher median anti-S IgG antibody titers. Participants vaccinated with the mRNA-1273 vaccine had the highest median anti-S-antibody level of 13,720.9 AU/mL (IQR 6426.5 to 30,185.6 AU/mL) followed by BNT162b2 (median, 7570.9 AU/mL; IQR, 3757.9 to 16,577.4 AU/mL); while the median anti-S antibody titer for non-mRNA vaccinated participants was 3759.7 AU/mL (IQR, 2059.7–5693.5 AU/mL). The median time to reach the lowest quartile was 3.53 months (IQR, 2.2–4.5 months) and 7.63 months (IQR, 6.3–8.4 months) for the non-mRNA vaccine recipients and Pfizer vaccine recipients, respectively. However, more than 50% of the Moderna vaccine recipients did not reach the lowest quartile by the end of the follow-up period. This evidence on anti-S IgG antibody titers should be considered for informing decisions on the durability of the neutralizing activity and thus protection against infection after the full course of primary vaccination in individuals receiving different type (mRNA verus non-mRNA) vaccines and those with natural infection.The World Health Organization (WHO) - grant number [2021/1183356-0]

Redefining effect modification

The odds ratio (OR) has been misunderstood in evidence based medicine and clinical epidemiology. Currently, “noncollapsibility” is considered a problem with interpretation of the OR and it is thought that the OR is rarely the parameter of interest for causal inference or interpretation of effect modification. The current focus on the relative risk (RR) and risk difference (RD) suffers from an important limitation: they are not solely measures of effect and vary numerically with baseline risk. In this paper, generalized linear models are examined in terms of the three binary effect measures commonly used in epidemiology to demonstrate that ORs may be the only way to interpret effect modification and have properties that should make them the parameter of interest for causal inference. We look forward to discussion, debate, and counter-views on this issue from the epidemiology community.This work was made possible by Program Grant #NPRP-BSRA01-0406-210030 from the Qatar National Research Fund (a member of Qatar Foundation). The findings herein reflect the work and are solely the responsibility of the authors. All authors had full access to all the data in the study and the corresponding author had final responsibility for the decision to submit for publication

Determining the conclusiveness of a meta-analysis.

The pursuit of conclusive evidence related to an unanswered foreground (decision-making) question has been the driving factor behind multiple ongoing and planned randomized controlled trials as well as meta-analyses. However, a fundamental challenge lies in establishing robust methods for ascertaining whether a collection of synthesized trials has yielded a definitive answer to that foreground question through the process of meta-analysis. This article explores the evolution of methods that attempt to address this challenge. These methods have primarily focused on defining and measuring the sufficiency and stability of evidence within a meta-analytic context. Cumulative meta-analysis and trial sequential analysis are the tools currently used, but they both come with limitations and challenges. We further discuss methods aimed at evaluating the evolution of effects over time more directly, such as the recursive cumulative meta-analysis. The latter method can be considered a better alternative, as it serves to demonstrate whether there is a true underlying treatment effect to which the meta-analysis is converging. However, recursive cumulative meta-analysis falls short of a specific indicator that establishes whether convergence has been reached. We coin the term exit for a meta-analysis where convergence can be demonstrated. Developing methods to determine the exit status of a meta-analysis is the next priority in research synthesis methods, as it will indicate that the research journey has concluded on a particular foreground question with no expectation of a different result with the addition of future trials.This work was made possible by Program Grant #NPRP-BSRA01-0406-210030 from the Qatar National Research Fund

COVID-19 infection across workplace settings in Qatar: a comparison of COVID-19 positivity rates of screened workers from March 1st until July 31st, 2020

Abstract Introduction COVID-19 transmission was significant amongst Qatar’s working population during the March–July 2020 outbreak. The study aimed to estimate the risk of exposure for COVID-19 across various workplace settings and demographics in the State of Qatar. Methods A cross-sectional study was conducted utilizing surveillance data of all workplaces with 10 or more laboratory-confirmed cases of COVID-19. These workplaces were categorized using a mapping table adapted from the North American Industry Classification System (NAICS) codes, 2017 version. The data was then analyzed to estimate and compare the positivity rate as an indicator of the risk of developing COVID-19 infection across various workplace settings in the State of Qatar. Results The highest positivity rate was reported amongst the Construction & Related (40.0%) and the Retail & Wholesale Trade sectors (40.0%), whereas, the lowest positivity rate was attributed to the healthcare workplace setting (11.0%). The highest incidence of COVID-19 infections occurred in South Asian nationalities and in the male gender. The private funded sector employees have seen higher positivity rate than employees of the governmental funded sector. Conclusion The elevated risk of infection in Construction and Retail & Wholesale Trade is probably due to environmental and educational vulnerabilities. The predominant labor force of those workplace categories is South Asian craft and male manual workers. Alternatively, the better containment of the healthcare workplace setting can be attributed to the enforcement of infection control and occupational safety measures. These findings imply the importance of using preventive and surveillance strategies for high-risk workplace settings appropriately

Duration of COVID-19 mRNA Vaccine Effectiveness against Severe Disease

Waning immunity following administration of mRNA-based COVID-19 vaccines remains a concern for many health systems. We undertook a study to determine if recent reports of waning for severe disease could have been attributed to design-related bias by conducting a study only among those detected with a first SARS-CoV-2 infection. We used a matched case-control study design with the study base being all individuals with first infection with SARS-CoV-2 reported in the State of Qatar between 1 January 2021 and 20 February 2022. Cases were those detected with first SARS-CoV-2 infection requiring intensive care (hard outcome), while controls were those detected with first SARS-CoV-2 infection who recovered without the need for intensive care. Cases and controls were matched in a 1:30 ratio for the calendar month of infection and the comorbidity category. Duration and magnitude of conditional vaccine effectiveness against requiring intensive care and the number needed to vaccinate (NNV) to prevent one more case of COVID-19 requiring intensive care was estimated for the mRNA (BNT162b2/mRNA-1273) vaccines. Conditional vaccine effectiveness against requiring intensive care was 59% (95% confidence interval (CI), 50 to 76) between the first and second dose, and strengthened to 89% (95% CI, 85 to 92) between the second dose and 4 months post the second dose in persons who received a primary course of the vaccine. There was no waning of vaccine effectiveness in the period from 4 to 6, 6 to 9, and 9 to 12 months after the second dose. This study demonstrates that, contrary to mainstream reports using hierarchical measures of effectiveness, conditional vaccine effectiveness against requiring intensive care remains robust till at least 12 months after the second dose of mRNA-based vaccines