730 e-Letters

  • Response to the article: Progression of disease preceding lower extremity amputation in Denmark: a longitudinal registry study of diagnoses, use of medication and healthcare services 14 years prior to amputation

    Response to the article: Progression of disease preceding lower extremity amputation in Denmark: a longitudinal registry study of diagnoses, use of medication and healthcare services 14 years prior to amputation.

    This article presents an impressive 14 year-long longitudinal study demonstrating the crucial importance of identifying and understanding the progression of lower extremity amputation (LEA)- related diseases. In doing so, health care providers are better prepared to address and potentially eliminate contributing risk factors. As mentioned by the researchers, only a few previous studies have inquired about the progression of diseases and use of health care services related to lower extremity amputations using historical longitudinal data.

    I personally found this article extremely interesting and very well detailed regarding patient demographics, comorbidities, prevalence of prescribed medication, and contacts made to hospitals and general practitioners (GPs). I particularly liked the strong emphasis made on the importance of disease prevention and early symptom recognition in order to treat patients earlier and avert complications.

    What did stand out to me, however, was that a significant portion of the sample had low education in regards to years of schooling. 88% of the sample had less than 9 years of school education which makes me question if educational status played a more significant role in disease progression than what was mentioned...

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  • Interpreting the carcinogenicity of social and medical development - Reply to the letter by Freitas-Junior et al. on 15 October 2017

    Dear Editor:

    We thank Freitas-Junior et al. for their detailed letter, which we read with great consideration, specially coming from leaders of the Brazilian Mastology Society.
    We will reply starting from the points that we believe that we all agree. First, that breast cancer mortality is linked to “social and medical developments”. Better health and higher life expectancy are associated with indicators of social development, such as Human development index (IDH), higher income and education. But better health is not necessarily associated to more health care (1). People of higher income may have more cancer not because of their wealth (which was expected to protect them), but because they are subjected to higher “observational intensity”, the combined effect of factors such as the frequency of screening and diagnostic exams, the ability of the exams to detect small irregularities, and the threshhold used to label results as abnormal, which can be an undesirable consequence (overdiagnosis) of medical development. As pointed by Welch and Fisher (2017), “Excessive testing of low-risk people produces real harm, leading to treatments that have no benefit (because there is nothing to fix) but can nonetheless result in medication side effects, surgical complications, and occasionally even death” (1).
    We also agree that radioprotection and radioinduced breast cancer are important issues to be addressed in a benefit-harm rationale, but we believe that the harm...

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  • Vitamin D induced effect on inflammation Via Oxidative Stress

    We have read the respective authors. We agreed with their all listeratire and proposed protocols but we would like to add in the effect of Vitamin D on oxidative stress followed by its impact on inflammation in obesity or diabetes or diet restriction/non restriction states to be highlighted. With them the impact of article will be more wider and more focused though insulin resistance is not being addressed with these vitals.

  • Breast cancer mortality and associated factors in São Paulo State, Brazil: two flaws need to be acknowledged

    Dear Editor:
    On reading the study conducted by Diniz et al. on the possible association between mammography and breast cancer-related mortality in the state of São Paulo, Brazil, I found two weaknesses that cannot go unnoticed. The authors have gathered information on mammography ratio and discussed the presumable effect on mortality of mammographic screening. These are two different situations. Having a mammogram is not the same thing as being screened with mammography. There are other reasons for having a mammogram, as having a palpable lump, being prepared for breast cancer surgery or systemic treatment, following up patients treated for breast cancer, orienting breast biopsies. When studying a population comprised of people who have actually died of breast cancer, one should expect to find a cluster of mammograms performed for non-screening purposes. And one should expect a higher mortality rate from breast cancer in this population.
    The other weakness is perhaps easier to understand for those familiar with health care in Brazil. It is very well known that death certificates in Brazil do not always reflect the actual cause of death. It is to be expected a serious under notification in the public health sector as compared to the private health sector. I do acknowledge that the mortality information system in Sao Paulo state is extensive in its coverage and that could be perceived as a strength of the article. However, one has to make sure that the rate of ad...

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  • Response to Kan et al.

    Kan et al. nicely showed that in HIV-infected treatment-naïve first-line regimen initiators, four-year risk of virological failure (VF) and HIV drug resistance (HIVDR) were 11.8% and 5.0%, and they demonstrated that male and female participants had different risk factors for VF and HIVDR[1]. However, there are some limitations in this study that might be worth mentioning. First, in the inclusion phase, as the authors acknowledged, over half of the participants included in 2008 were lost to follow-up or excluded in 2012, which may generate selection bias. Hence, it would be important to compare the baseline characteristics in participants lost to follow-up/excluded and those who were included, in order to see whether there were any significant differences that may bias this study. Second, the authors did not account for baseline transmitted drug resistance mutation (DRM). Albeit rare, the prevalence of DRM was still 3% in treatment-naive participants in the year 2008, based on a meta-analysis[2]. As shown in a previous study in China with participants starting antiretroviral therapy (ART) between 2008-2010, baseline DRM is significantly associated with virological failure[3]. Coincidentally, this study found that HIVDR rate was 5.0%, comparable to the baseline DRM rate in the aforementioned meta-analysis. Thus, baseline DRM may actually affect HIVDR rate in this group of participants. Third, this study did not include men who have sex with men (MSM), which have become one o...

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  • Misinterpreting the message

    Dear Authors,

    Many thanks for your article regarding the safety of low alcohol consumption in pregnancy. Interestingly we heard about this article on BBC radio 4 news, while driving during rush hours, which came to us as a surprise. Having read through this comprehensive literature review, it is clear that current guidelines do not appreciate low alcohol consumption in pregnancy.

    Being doctors, it is clear to us that the risks are low, however media portrayal of this article came across that alcohol is medically acceptable in pregnancy. This argument may lead to unnecessary justification of alcohol use during pregnancy increasing vulnerability of foetus to future risk. It is eye-catching article for media and hence got a lot of attention however potentially a misleading article, which could be misinterpreted in the wrong hands, with risks not only to mothers but also to their children.

    We appreciate that although this article has looked into available literature showing little evidence for the effects of low alcohol consumption in pregnancy, and that further research in this field may come across ethical issues. However, we do feel that extrapolating this lack of evidence to make assertions such as “safety” of alcohol in pregnancy could potentially be harmful.

    Alcohol consumption in pregnancy is advised against due to the risk of foetal alcohol syndrome and other complications to the mother. Given these risks it is important to send a clear...

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  • RE:One misinterpretation

    We thank Mr/Ms Lin for the comments regarding our recent report (Long et al., 2017). We updated a meta-analysis on the association of smoking with NPC risk.
    We agree with Mr/Ms Lin that Lin rightly stated that his/her paper used 'mortality' as the outcome, but the authors reported 'incidence' in the meta-analysis. We have to point out that we did include some valuable articles including Lin’s regarding the mortality or morbidity of NPC to make the review more comprehensive. However, we excluded these in the summary statistics of NPC incidence. For example, we did not Include Lin’s data in Figure 2.

    We agree with Lin in that a meta-analysis of individual participant data (IPD) is needed to clarify the association between smoking and NPC. However, we do not think it is so called “a gold standard”. Instead, we recommend a novel Mendelian randomization analysis (MRA) approach. Using a gene-environment interaction and pathway analysis, we designed MRA to clarify the causal role of environmental exposures such as cigarette smoking in carcinogenesis (Fu et al 2012), because it is always difficult to address or clarify causal-effects by observational studies. We have used this strategy and clarified the causal role of red meat (Fu et al 2012) and cigarette smoking (Fu et al 2013) in pathogenesis of colorectal polyps, the precursors of colorectal cancer. This strategy was highlighted and orally presented in AACR annual meeting 2012 (...

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  • Not a random sample

    Thank you for an interesting paper. The authors claim that women were selected using a systematic random sampling technique. However, their report states that 'The first served pregnant woman and every second woman thereafter were invited to participate in the study until the required sample size was obtained.' This assumes that the women attended the clinic in random order. I they did attend in random order, then selecting every woman consecutively would produce an equally random sample. If there was some pattern to their attendance, then this is not a random sample. I think it would be more accurate to say that this was a convenience sample.

  • Response to comment on statistic

    Thank you for raising this important point. Actually, the Poisson regression is usually used for count data with the variance equal to the mean. And Likert scale data is not suited to this statistic method directly. However, we standardized the scale and the data acquisition for the disability status within 30 days. We assumed that the standardized scores of each domain and summary score (from 0 to 100) as the count of disability status event in 30 days. For analysis the association between the variables of demographic data and standardized WHODAS 2.0 score, we choose the Poisson regression analysis, which could not be perfect for this study. (And the data is near to 1 even statistical significant) Therefore, we didn’t mention the outcome of table 3 in discussion part and conclusion part (merely, mentioned in result part). Our study finding is based on table 2 and we discussed this finding (lower disability status in the WHODAS 2.0 domains of getting along and social participation for patients with dementia with formal education compared with those without formal education) in discussion and conclusion part.

    Thank you again for your precious suggestion. We agree that Multi-level IRT could be an appropriate way to analyze multiple Likert scales. The following studies of original Likert scales of WHODAS 2.0 will be analyzed as your suggestion and this could lead our study to be more convincing.


  • One misinterpretation

    We appreciate this updated meta-analysis on smoking and NPC. However, one misinterpretation of our paper (Lin et al., 2015) was found.
    The paper used 'mortality' as the outcome, but the authors reported 'incidence' in this paper.
    The authors stated, the lack of individual participant data for adjustment of potential confounders. We agree that as a gold standard, a meta-analysis of individual participant data is needed to clarify the association between smoking and NPC.