key: cord-0747671-1u2y7ix7 authors: Bilal, Bushra; Saleem, Faizan; Sadia Fatima, Syeda title: Alcohol consumption and obesity: the hidden scare with COVID-19 severity date: 2020-09-16 journal: Med Hypotheses DOI: 10.1016/j.mehy.2020.110272 sha: c2b199313d661187a7586c031bd8f1d2384ace2b doc_id: 747671 cord_uid: 1u2y7ix7 Obese individuals seem to be at the highest risk of contracting COVID-19 infection. Furthermore, more severe cases and mortality is reported in the developed world as compared to the developing world. One probable reason for this difference could be the difference in living conditions and exposure to other infections. Secondly, the difference in food especially, alcohol use may have deteriorating effects superimposed with obesity. Our hypothesis suggests that a combination of alcohol consumption and obesity causes low immunity and makes the person prone to develop ‘cytokine storm’ and ‘acute respiratory distress syndrome’; the hallmark of COVID-19 mortality and morbidity. Thus, reducing any one trigger can be beneficial to combat the disease severity. Obese individuals seem to be at the highest risk of contracting COVID-19 infection. Furthermore, more severe cases and mortality is reported in the developed world as compared to the developing world. One probable reason for this difference could be the difference in living conditions and exposure to other infections. Secondly, the difference in food especially, alcohol use may have deteriorating effects superimposed with obesity. Our hypothesis suggests that a combination of alcohol consumption and obesity causes low immunity and makes the person prone to develop 'cytokine storm' and 'acute respiratory distress syndrome'; the hallmark of COVID-19 mortality and morbidity. Thus, reducing any one trigger can be beneficial to combat the disease severity. In December 2019, several patients represented the symptoms of acute respiratory illness in Wuhan, Hubei province, China. The causal agent of COVID-19 has been identified as a newly discovered member of Corona virus family and has been named as SARS-COV-2 (1). SARS-COV-2 possesses the propensity to be released from the infected individual in to the environment through respiratory droplets, it has rapidly taken over and has been characterized as pandemic affecting ~11,756,093 individuals and ~541,079 deaths around the globe as of 7 th July, 2020 globally until now (www.covidvisualizer.com). Interestingly, symptoms of COVID19 infection are non-specific, thus speculation regarding the total number of actual cases may be underestimated because people are mild and asymptomatic cases go largely undetected. A balance nutrition is required to maintain good immunity which is essential for prevention and management of this viral infection (2) . This is in concordance with a good organ function especially liver and spleen that not only get rid of the toxins but also provide safety against common infections. One plausible cellular/immunological disruption that can effect the immune cells is the combination of obesity and alcohol consumption, which might be involved in severity of COVID-19 pathogenesis [ Figure 1 ]. Figure 1 : Flow path-showing relationship between alcohol consumption/obesity and COVID19 pathogenesis. In brief, an increased production of adipose tissues can lead to onset of inflammatory responses that might result in higher production of inflammatory cytokines of such as TNF-α, IL-8 and ACE II receptors. High alcohol consumption on the other hand can exert the same effect on the regulation of TNF-α, IL-8 and ACE II receptors. Both of these perturbed dietary habits lead to potential increase in severity of COVID-19 pathogenesis. Alcohol consumption has been characterized as one of the leading causes of acquired community disorders (3). Approximately 2.4 billion people (1.5 billion males; 0.9 billion females) consume alcohol around the globe with regular intervals (4) . Alcohol consumption has been reported to affect the immune-related health responses and might just put an individual at risk for acute respiratory stress syndrome (5) . Acute respiratory distress syndrome (ARDS) is related with an over production of chemokines, termed as "cytokine storm"; a common occurrence with COVID-19 infections. Recent studies on immune-compromised models have also emphasized that heavy alcohol consumption has been associated with overproduction of inflammatory cytokines by hepatic cells, leading to elevated inflammatory (6, 7) . More specifically, it has been observed that the levels of Interleukin-8 and TNF-α increase by significant proportion in response to even acute alcohol consumption (8) (11, 12) . Furthermore, the increase expression of ACE2 receptors also lead to enhance TNF-α cytokine cytotoxicity (11) , which relates both to the molecular (SARS-COV2 receptor interaction) as well as immunological (Cytokine storm) aspects of COVID19 pathogenesis. These molecular and immunological clues can be a suggestive of how acute respiratory distress syndrome (ARDS) prone environment is generated during COVID19 pathogenesis in alcohol consumers. Moreover, since last decade obesity and respiratory dysfunction has been a point for interest for the scientific community and it has been implied that even without any ongoing or prior respiratory illnesses, the people suffering from obesity demonstrate breathlessness and dyspnea patterns which might become more severe in case of respiratory pathogenesis (13) . For instance, obesity is linked with higher mortality rate of H1N1 infected patients (14) , and time required for virus shedding is increased by 42% in obese H1N1 infected patients (15) . Hence, obese individuals may retain respiratory viral infection for a longer duration of time and in severe cases are more prone to life threatening chronic illnesses. A recent study has characterized obesity as the major factor for increased mortality rate in SARS-COV-2 infected individuals, it was observed that the patients having a BMI and age of ≥ 34 and ≥ 30, respectively were more prone to severe COVID19 symptoms (16) . Possible explanation regarding such a trend could lie in metabolic/immunological and bleeding discrepancies associated with SARS-COV-2 infection. As discussed in previous section both these immunological markers have also been concomitant with alcohol ingestion and COVID19 pathogenesis. Approximately 31% patients suffering from COVID-19 develop thrombotic complications (17) . More specifically, an increase in D-dimer protein fragment and enhanced prothrombin time was observed in 46% of critically ill COVID19 infected individuals (18) . Around of total observed patients demonstrated 0.5 mg/L increase in D-dimer, while they also demonstrated an increase of approximately 15-16 seconds in prothrombin time (19) (20) (21) . Such changes might be related to increase levels of interleukin 8 (IL-8) and Tumor necrosis factor alpha (TNF-α) in obese individuals (22) . Increase levels of interleukin-8 (IL-8), Tumor Necrosis Factor Alpha (TNF-α) seems to be a common factor in alcohol ingestion/obesity complications and COVID19 pathogenesis. Although, several studies have implied such changes but none of those have been able to correlate these trends together in terms of COVID19 pathogenesis. Obesity cannot be modified on urgent basis, but a negligible alcohol consumption might reduce the severity of the COVID-7 Severe acute respiratory syndrome-related coronavirus: The species and its viruses-a statement of the Coronavirus Study Group Enhancing immunity in viral infections, with special emphasis on COVID-19: A review Alcohol and the risk of pneumonia: a systematic review and meta-analysis Are patients with alcohol use disorders at increased risk for Covid-19 infection? 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Impact of obesity on influenza A virus pathogenesis, immune response, and evolution Obesity increases the duration of influenza A virus shedding in adults Obesity is a risk factor for greater COVID-19 severity Incidence of thrombotic complications in critically ill ICU patients with COVID-19 Coagulation abnormalities and thrombosis in patients with COVID-19, The Lancet Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan Abnormal coagulation parameters are associated with poor prognosis in patients with novel coronavirus pneumonia Clinical features of patients infected with 2019 novel coronavirus in Strac o s i, S ienis-Strac o s a, A St pie , I. Kowalska, M. Szelachowska and I Plasma interleukin-8 concentrations are increased in obese subjects and related to fat mass and tumor necrosis factor-α system The authors declare that they have no conflict of interest.