Introduction
There is a suspicion that there is an association between reserpine use and the risk of breast cancer development. According to the table of Annual age-adjusted incidence of breast cancer per 100,000 women by body weight and reserpine status, this prediction may match reality. It depicts that people, who apply reserpine on a regular basis, are more likely to have breast cancer in the future. The index for reserpine user is 10.47, while it is 6.14 for other ones. It is evident that there is a connection between reserpine use and the liability to breast cancer development (Abdelfatah & Efferth, 2015). However, it is worthy of taking into consideration that the impact is relatively weak.
Another issue, which causes multiple concerns, regards the built of an individual. There is an assumption that obesity increases the chances of having breast cancer (Argolo et al., 2018). The table, which has already been mentioned above, presents that there is a considerable difference in morbidity statistics. The index of the liability to breast cancer is 8.72 among obese individuals, while it is 4.22 among people with normal built. For this reason, it is possible to conclude that there is obesity may lead to increasing the risk of breast cancer development.
After reviewing the table and the possible risk factors, a logical question follows concerning the possible association between reserpine use and obesity. The table demonstrates that the index for the individuals, who reject reserpine, is 4.10 for normally-built ones and 8.30 for obese participants, while reserpine users have an index of 6.40 and 12.50, respectively. Therefore, it is apparent that the suspicion matches reality, though it is not impactful to a large extent.
In summary, it should be noted that all the aforementioned factors are not significant in the context of the liability to breast cancer development, though their minor influence is undeniable. Whether reserpine use and obesity are combined in a single case, their impact cannot be underestimated (Siddiqui et al., 2020). However, there is no evidence that the association between reserpine and breast cancer is attributable to obesity.
Chronic Obstructive Pulmonary Disease
The focus of the 20-year study is to explore the connections between chronic obstructive pulmonary disease (COPD) and such factors as low SO2 and low FEV1. The participants were copper smelters with high SO2 and truck maintenance workers with low SO2. It should be noted that the majority of them, namely 55% of each group, were smokers. The results revealed that the risk of COPD was significantly higher among smelter with a smoking habit as compared to truck maintenance workers. Therefore, it is apparent that a high SO2 level has an influence on the liability to COPD, as well as smoking on a regular basis.
FEV1 is an important measure for evaluating COPD and monitoring the progression of the disease. The normal result varies from person to person, considering such specialties as age, race, gender, and others. It is helpful in identifying the current stage of COPD (Agusti & Faner, 2018). However, it is not applied for revealing this disease, as another breathing measure named FVC is also required in order to be precise in establishing a diagnosis. The combination of FEV1 and FVC helps to present a comprehensive picture of the lung condition (Agusti & Faner, 2018; Lange et al., 2016). For determining the exact impact of COPD, CAT is also applied. Therefore, FEV1 is the amount of air the patient is capable of forcing in one second, and this measure can be used to diagnose other diseases. For instance, low FEV1 may demonstrate the sign of asthma, and for this reason, it cannot be considered an independent risk factor for COPD. Consequently, it presents the best reason for not controlling for low FEV1 as a potential confounder.
Oral Contraceptive Use, Plasma Homocysteine Level, and Myocardial Infarction
There is a suspicion that oral contraceptive use may lead to myocardial infarction. Roach et al. state that “Combined oral contraceptives (COCs) have been associated with an increased risk of arterial thrombosis, i.e. myocardial infarction or ischemic stroke” (2015, para. 1). Two possible causal models, which include oral contraceptive use (OC), plasma homocysteine level (HCS), and myocardial infarction (MI), exist. One approach implies the development of MI on the basis of the combination of OC use, HCS factor, other circumstances, which are highly likely to result in the liability to the disease. Therefore, the range of factors leads to MI, and in this case, HCS may be considered to be a confounder of the relationship between OC and MI.
Moreover, there is another sequence of factors, which may end in MI. There is a causal model that implies another connection between OC use and the risk of MI. In this model, HCS may appear to be an interim step, namely applying OC may lead to HCS and then, combined with other risk factors, result in MI. Consequently, analyzing the relationship between OC and MI, in this case, HCS is not a confounder.
Contraception Methods and Their Risks
The Oxford Family Planning Association Contraceptive Study was applied to divide the participants into three groups in accordance with the contraception methods they prefer to use. The study reviews such methods as oral contraception, diaphragm contraception, and intrauterine device (IUD). After reviewing the table, which depicts the results of the research, and the factors mentioned in it, it is possible to note that there are some aspects that may present the sources of bias.
The first one is the factor “percentage aged 25-29 years”. It becomes evident that there are participants, who refer to other age groups, and the results on them are not covered comprehensively. In addition, participants aged 25-29 are not the majority of using the chosen methods of contraception. This aspect may be the cause of misunderstanding of the study. The second issue, which may lead to bias, is “percentage in Social Classes I or II”, which may appear not to be informative, considering the topic of the study. The third bias regards the “percentage smoking 15 or more cig./day” characteristics. This point reveals only the ones, who some actively on a regular basis, though does not pay attention to the individuals, who have the same habit, but preferred to use fewer cigarettes. Other applicants may be considered to be non-smokers, which is highly likely no to match reality.
It is apparent that the study is difficult to be perceived objectively. Moreover, the aforementioned biases may lead to an improper understanding of the relationship between oral contraceptive use and circulatory deaths. Another aspect, which should be highlighted in this context, is the duration of using this method, which appears to have a significant impact on the health state. Apart from this, the factor of age should be broadened and taken into consideration.
References
Abdelfatah, S. A. A., & Efferth, T. (2015). Cytotoxicity of the indole alkaloid reserpine from Rauwolfia serpentina against drug-resistant tumor cells. Phytomedicine, 22(2), 308-318.
Agusti, A., & Faner R.(2018). COPD beyond smoking: New paradigm, novel opportunities. The Lancet, 6(5), 324-326.
Argolo, D. F., Hudis, C. A., & Iyengar, N. M. (2018). The impact of obesity on breast cancer. Curr Oncol Rep, 20(47).
Lange, P., Halpin, D. M., O’Donnell, D. E., & MacNee, W. (2016). Diagnosis, assessment, and phenotyping of COPD: Beyond FEV₁. International journal of chronic obstructive pulmonary disease, 11 Spec Iss, 3–12.
Roach, R. E., Helmerhorst, F. M., Lijfering, W. M., Stijnen, T., Algra, A., & Dekkers, O. M. (2015). Combined oral contraceptives: The risk of myocardial infarction and ischemic stroke. Cochrane Database of Systematic Reviews, 8.
Siddiqui, M., Bhatt, H., Judd, E. K., Oparil, S., & Calhoun, D. A. (2020). Reserpine substantially lowers blood pressure in patients with refractory hypertension: A proof-of-concept study. American Journal of Hypertension, 33(8), 741–747.