302 e-Letters

  • Covid-19 vaccination intentions in Belgium

    Interested readers should note a relevant Belgian study on this subject was not cited. It repetitively obtained COVID-19 vaccination intentions before and after vaccine introduction in Belgium in 2020 and 2021, and reported results in real time through reports and press releases (see www.corona-study.be), noting the high general vaccination intentions (in closer accordance with the official records of actual coverage than the pre-implementation references cited here) and most of the socioeconomic disparities reported here. These results were also published after peer review in January 2022 for the pre-implementation period in Flanders, the largest region of Belgium (see Valckx et al, Vaccine 2022 at https://www.sciencedirect.com/science/article/pii/S0264410X21014146 ).

  • Re: Effort-reward imbalance and long-term benzodiazepine use: longitudinal findings from the CONSTANCES cohort

    Airagnes et al. examined the association between effort–reward imbalance and incident long-term benzodiazepine use (LTBU) (1). The effort–reward imbalance was calculated in quartiles, and the adjusted odds ratios (95% confidence intervals) of the third and fourth quartiles of effort-reward imbalance for incident LTBU over a 2-year follow-up period were 1.74 (1.17 to 2.57) and 2.18 (1.50 to 3.16), respectively. They also clarified a dose-dependent relationship and an
    interaction of tobacco smoking on the relationship. I have a comment with special reference to the number of subjects with LTBU during follow-up in each sex.

    About two thirds of subjects with LTBU during follow-up were women. The same authors reported that the prevalence of long-term prescribed benzodiazepine use in the French population was 2.8% in men and 3.8% in women in the year 2015 (2). Although the total percentage of subjects with LTBU during follow-up was under 1%, there are differences in the long-term prescription percentage between men and women. As the authors observed the interaction of tobacco smoking on the relationship, I recommend the additional analysis, which should be stratified by sex, according to their previous cross-sectional study (3).

    1. Airagnes G, Lemogne C, Kab S, et al. Effort-reward imbalance and long-term benzodiazepine use: longitudinal findings from the CONSTANCES cohort. J Epidemiol Community Health. 2019 Nov;73(11):993-1001.
    2. Aira...

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  • Sex and age differences in adverse events following seasonal influenza vaccines: comment on the article by Kiely et al.

    The article by Kiely et al., which reported a higher risk of injection site reactions in women than men for both younger and older participants, is interesting. The risk of systemic reactions was also higher following influenza vaccination in women than in men, irrespective of age and vaccine type.1 These findings are a valuable addition to the literature. However, we have two concerning issues for the authors.
    First, there is underreporting, which occurs in any adverse events following vaccine or drug studies based on spontaneous reporting.2 Underreporting is a problem in adverse events studies following vaccination using self-reported data. This may lead to a bias away from the null value, and they are susceptible to response bias, social desirability bias, and misclassification.3 Therefore, with underreporting, the conclusions may not be rigorous.
    Second concern is the possibility of age and sex differences in adverse events following seasonal influenza vaccination. Previous studies have shown that elderly women have higher humoral responses against influenza than elderly men, but not young women compared with young men.4,5 Some authors have also reported sex and age differences in influenza vaccination. Elderly women typically suffered more frequently from local and systemic side effects because antibody induction is usually higher elderly women than in elderly men after vaccination. Consequently, the sex-related difference observed would not be the true di...

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  • To improve validity in population-based prospective cohort study: comment on the article by Wei et al.

    An article by Wei et al. reported the death of a child associated with an increased risk of incident atrial fibrillation (AF). The association was observed when the cause of death was both cardiovascular and non-cardiovascular diseases.1 These findings provide a valuable addition to the literature; however, some issues were not addressed by the authors.
    First, several clinical risk factors are associated with incident AF, including concurrent medication, illegal drugs, obesity, sleep apnea, and hyperthyroidism.2-4 For example, we previously reported that insulin users had a higher risk of incident AF than non-users among the elderly patients’ cohort (1.58 odds ratio (OR); 95% confidence interval (CI): 1.37–1.82). Patients with dipeptidyl peptidase 4 inhibitor (OR 0.65; 95% CI: 0.45–0.93) intake had a lower risk of developing AF when compared with non-users.4 However, while associated evaluations were not presented, Wei et al. did not exclude individuals with these risk factors. Consequently, confounding effects may have contributed to the significant effects causing incident AF, thus, omitting these effects may improve study validation outcomes.
    Second, the study initially enrolled 2,740,028 participants in the unexposed group and 64,216 participants in the exposed group at baseline, but missing data between groups (50.1% vs. 79.6%) were examined in further analyses. These missing data potentially affected data credibility in mediation analyses.5 Consequent...

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  • Discrepancies in Mental Health Impacts

    While the data that this article studied and the results that were produced show a change in the mental health status and medication behaviors of Portugal, it does not support the change in mental health status captured in much of the literature around the world. When the COVID-19 virus was declared a pandemic, there was global unrest. It is natural for people to feel fear, anxiety, and panic in the face of an unknown pandemic (Usher, Durkin, & Bhullar, 2020). The article addresses some of the discrepancies between the literature coming out that has been showing increases in anxiety and depressive symptoms in the Discussion section. However, these discrepancies do not align with the data presented in the paper. Further explanation and research is needed as to why rates of some prescription medications to manage mental health symptoms are declining when there is evidence showing that mental illnesses have increase as a result of the pandemic.
    The article discussed a reduction of prescriptions for anxiolytics, sedatives, and hypnotics in children, adolescents, and elderly women. These medications would address the symptoms of anxiety, stress, and other symptoms that a global pandemic may cause (Javed, Sarwer, Soto, & Mashwani, 2020). The authors suggested that perhaps people have been going to see the doctor less frequently due to quarantines and fear of contracting the virus. However, some of the medications are long-term, so it does not make sense that, duri...

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  • The importance of ethnicity and race variables in epidemiology and public health

    The authors, Cifuentes MP, Rodriguez-Villamizar LA, Rojas-Botero ML, et al [1], present an article that, owing to a lack of rigor in the creation and application of ethno-racial categories, ends up employing an analysis method that, although intended to allow proving inequalities, ends up disguising or attenuating them.

    Raj Bhopal published a seminal article in this journal in 2004 demonstrating the importance of ethnicity and race variables in epidemiology and public health. Bhopal pointed out that, at a minimum, researchers should explain their understanding of the concepts of race or ethnicity and the classification they use, even more so when we know that they need development in terms of geographic specificity, scope, and precision for different contexts [2]. Similar recommendations are made by Janeth Mosquera in her analysis about the use of the ethnic-racial category in the research published by the three most important scientific journals of Public Health in Colombia [3].

    The paper does not present a comprehensive and helpful description of the categories that assist the reader in understanding the ethnic-racial composition of the Colombian population and correctly analyze the regularly available data for public health surveillance. The Colombian surveillance system employs the census ethnic-racial categories. Among these Census categories, the "white-mestizo" used by the authors is not defined and thus is not used for public health surveill...

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  • ICNIRP Response to: John William Frank “Electromagnetic fields, 5G and health: what about the precautionary principle?”

    Frank’s essay contains several statements about 5G, its relation to the radiation protection science, and related to this, ICNIRP’s guidance and integrity more generally. ICNIRP considers this to be seriously inaccurate and in need of correction for the sake of both scientific accuracy and development of effective public health policy. However, due to journal word limits we must restrict our response to Frank’s misleading claims about ICNIRP’s integrity (for full response see https://www.icnirp.org/en/activities/news/index.html).

    Frank’s essay accuses ICNIRP of unmanaged conflict of interests, and uses this accusation to attempt to throw doubt on ICNIRP’s scientific evaluations. However, ICNIRP has a very rigorous procedure to avoid conflicts of interest (https://www.icnirp.org/en/about-icnirp/commission/index.html), and Frank did not provide any evidence in support of his statement - he merely referred to ‘persistent allegations’ from the Swedish epidemiologist Lennart Hardell. For example, Frank repeats claims made by Hardell that “ICNIRP’s membership includes over-representation of vested interests, especially the giant multinational telecommunications firms who are heavily invested in the roll out of 5G systems internationally”, and no supporting evidence was provided by either author. To be clear, there are no industry r...

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  • Antidepressants and suicidality

    Hengartner et al. conducted a meta-analysis on suicide risk with selective serotonin reuptake inhibitors (SSRI) and other new-generation antidepressants in adults (1). Although the pooled relative risks (RRs) of SSRI for suicide risk including suicide and suicide attempt in patients with depression and in patients with all indications did not reach the level of significance, the pooled RR (95% confidence intervals [CIs]) of any new-generation antidepressant for suicide risk in patients with depression and in patients with all indications were 1.29 (1.06-1.57) and 1.45 (1.23-1.70), respectively. The authors presented information on the different suicide risk between SSRI and other new-generation antidepressants , and I present additional information regarding the relationship.

    First, Sharma et al. conducted a meta-analysis on the association of SSRI and serotonin-norepinephrine reuptake inhibitors with suicidality and other mental indicators (2). Although the pooled odds ratios (ORs) of antidepressant treatment for suicidality and aggression did not reach the level of significance in adults, the pooed ORs (95% CIs) of antidepressant treatment for suicidality and aggression were 2.39 (1.31-4.33) and 2.79 (1.62-4.81) in children/adolescents. The suicide risk differed in different generations, and suicide risk estimation should be conducted by stratification with generation and type of anti-depressants.

    Second, Hengartner and Plöderl reported that odds ratios (OR...

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  • Role of presymptomatic transmission of COVID-19: evidence from Beijing, China- A Response

    We read with interest, intrigue and concern the findings reported in this short report. if the findings are validated from larger and multicentric data this may have huge implications in the way we trace and isolate the COVID-19 contacts. Pre symptomatic transmission from index cases 5 days prior to the onset of symptoms is a huge logistical nightmare in terms of containment strategies. This would imply at practical impossibility and futility of these strategy especially in setting of cluster or community transmission. This also highlights the virtues of basic but universal measures like physical distancing, hygiene and use of mask at all times under specific settings.

  • Back to the topic: high cardiovascular mortality in Russia

    The question “Why does Russia have such high cardiovascular (CV) mortality rates?”1 can be answered by a pathologist who practiced during the Soviet time.2 Since then, the quality of post mortem examinations has decreased especially during the 1990s: autopsies were sometimes made perfunctorily. The deterioration in anatomic pathology and the health care in general during the 1990s coincided with the increase in the registered CV mortality. A tendency to over-diagnose CV diseases is generally known to exist also for people dying at home and not undergoing autopsy. If a cause of death is not entirely clear, it has been usual to write on a death certificate: “Ischemic heart disease with cardiac insufficiency” or a similar formulation.2 Concerning the relatively high CV mortality in Russia, it should be commented that irregular treatment of hypertension,3 diabetes and other chronic diseases continues to be a problem. Considering the above, the differences between Norwegian and Russian cohorts1 can be better understood. The levels of serum lipids were comparable between Russia and Norway being slightly higher in the latter possibly due to better nutrition. Interestingly, N-terminal pro-b-type natriuretic peptide (NT-proBNP), high-sensitivity cardiac troponin T (hs-cTnT), and high-sensitivity C-reactive protein (hsCRP) were higher in Russia.1 It can be reasonably assumed that average levels of these markers inversely correlate with a nation’s health reflected by the life expecta...

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