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Smoking and Comorbidities in COVID-19: A Systematic Review

COVID-19 is highly contagious, causing pneumonia, respiratory failure, death, and becoming a pandemic. Patients with severe infections must be treated in the Intensive Care Unit (ICU) with a ventilator. Ventilator facilities in the ICU are limited; it must take precautions by knowing the characteristics of patients at high risk of severe disease in COVID-19, one of which was smoking or comorbidity. The purpose of this study was to assess the risk of comorbidity and smoking in COVID-19. This study used systematic review by searching for articles from the ScienceDirect and Medline databases with journals published on January 1, 2019 March 31, 2020. The results of the study showed that there were 12 relevant articles full text in English and were analysed. The conclusion was that patients with COVID-19 who were smoking or had comorbidities were more susceptible to COVID-19 infection, more severe illness, and causing death. ©2020 Universitas Negeri Semarang pISSN 2252-6781 eISSN 2548-7604 Article Info Article History: Submitted April 2020 Accepted June 2020 Published July 2020


INTRODUCTION
The coronavirus was a virus discovered by Tyrell and Bynoe in 1996. This virus enveloped in a large single-stranded positive RNA in the shape of a spherical virion like a ball with a core projection and a surface that resembled a solar corona (Latin: corona = crown) that could infect humans and various kinds of animals (Velavan & Meyer, 2020). Coronavirus causes respiratory disease in the form of pneumonia, which can result in death and is highly contagious (Panahi, et al., 2020). The World Health Organization on March 11, 2020, stated that there was a pandemic from a new strand of the coronavirus family associated with the severe acute respiratory syndrome (SARS-CoV 2) (Rio & Malani, 2020). The virus was first discovered in December 2019 in Wuhan City, Hubei Province, China, which allegedly originated from the seafood market, where the carrier of this new type of coronavirus originated from chrysanthemum head bat and was officially named coronavirus 2019 (COVID-19) .
Every day, the number of people infected with COVID-19 continues to increase. Since it first appeared in China (Wuhan) until March 19, 2020, there were 234,073 people infected with COVID-19 and 9,840 people died (Panahi et al., 2020), and this virus has spread to 60 countries, including Indonesia (Adalja et al., 2020). At present, the COVID-19 virus infection is increasingly widespread, and the number of people infected is increasing so that the number of deaths is higher, which causes health care death (D. . Smoking is assumed to be a prognosis of the adverse disease, harms lung health, and causes various diseases such as cancer and respiratory diseases (Tonnesen et al., 2019). Smoking also damages immunity and its effectiveness in killing bacteria or viruses so that it can prevent infection. This study shows that smokers are more susceptible to infectious disease infections (Z. Zhou et al., 2016).
The available ICU facilities are not proportional to the increasing number of patients; it is necessary to know the characteristics of patients at high risk of severe disease in COVID-19. Smoking and comorbidities are the basis for reducing and preventing the risk of death in patients with COVID-19 infection.
This study aimed to get more reliable evidence through a systematic review to assess the risk of comorbidities and smoking in causing death in COVID-19 cases. The result is expected to provide overview guidance to perform responses and strategies to develop prioritizing procedure of ventilator utilization to prevent deaths in COVID-19 cases.
problems, global economic losses, and becomes a pandemic (Basile et al., 2020)a disease caused by a novel coronavirus, is a major global human threat that has turned into a pandemic. This novel coronavirus has specifically high morbidity in the elderly and in comorbid populations. Uraemic patients on dialysis combine an intrinsic fragility and a very frequent burden of comorbidities with a specific setting in which many patients are repeatedly treated in the same area (haemodialysis centres. In Indonesia, as of March 31, 2020, 1,528 people were infected with COVID-19, and 136 people died (8%), which is the highest percentage of mortality in the world (Gugus Tugas Percepatan Penanganan COVID-19, 2020).  reported, 13 patients (32%) from 41 COVID-19 cases had comorbidities such as cardiovascular disease, diabetes, hypertension, and obstructive pulmonary disease . Another study found that from 138 CO-VID-19 cases, 64 patients (46.4%) had comorbidities in which patients treated in intensive care units (ICU) had a higher number (72.2%) than those not treated in ICU (37.3%). This study showed that comorbidities can be an adverse risk factor and cause

METHODS
The steps of this systematic review were carried out based on the PRISMA protocol (Moher et al., 2015). It can be seen in Figure 1. The articles used were articles in the ScienceDirect and Medline databases published on January 1, 2019 -March 31, 2020. Searching used the keywords of "COVID-19" AND "comorbidities" and "COVID-19" AND "smoking" by checking each article to prevent any discrepancies with the specified topic. Management of study data and duplicate data used Mendeley v1.19.4 and qualitative synthesis used NVIVO 12 Plus software. The inclusion criteria in this study, namely the article must explain the characteristics and prevalence of the disease of patients with COVID-19, and the exclusion criteria, namely the case of COVID-19 in animals with SARS (Severe Acute Respiratory Syndrome) and Middle East Respiratory Syndrome (MERS) that are not relevant to COVID-19.

RESULT AND DISCUSSION
Article search results obtained 287 sources (68 from PubMed and 219 from ScienceDirect). The articles obtained were selected which relevant according to the research topic and deleted duplicates. There were 12 related articles in full text in English, and it was analyzed. It can see in Table 1 for the results of the analysis.
COVID-19 is a virus that infects the respiratory system, with three classifications of signs and symptoms such as mild, severe, and critical (Driggin et al., 2020;Jordan et al., 2020). Sign and symptoms begin with the same mild symptoms like flu, fever, fatigue, and dry cough , while sign and symptoms of severe infections such as shortness of breath, diarrhea, pneumonia and high fever (>39°C) (Giwa et al., 2020). The patient indicates severe show if they have pneumonia and dyspnea (W.J. . The patient means critical, if they have respiratory failure, septic shock, and multiorgan failure, and it can cause death (Jordan et al., 2020).
Most people who are infected with CO-VID-19 in the elderly, whereas in children, it is infrequent, and the number of cases is fewer (Lai et al., 2020). The most infected patients in China are men because many men smoke and are older people . Infected with CO-VID-19 signs and symptoms will appear depending on classification, such as mild cases: about two weeks, severe or critical illness: three to six weeks, time from onset to development of severe disease in one week. (World Health Organization (WHO), 2020). COVID-19 is estimated to be the incubation period for COVID-19 between 2 and 14 days (Lauer et al., 2020).
Factors causing COVID-19 patients to experience severe and critical symptoms are smoking and comorbidity (W. Jordan et al., 2020;Vardavas & Nikitara, 2020;Zhang et al., 2020), even COVID-19 patients who smoke can have chemicals in cigarettes contain hydrogen cyanide (HCN). If it enters the respiratory system, it becomes toxic to the ciliary cells lining the respiratory tract to function as the body's defense system to prevent the entry of foreign objects, including viruses and bacteria into the lungs so that COVID-19 can quickly enter the lung cells and damage the cells. Hence, the patient becomes short of breath and must be using a ventilator (Onor et al., 2017).
COVID-19 patients in China who experience severe symptoms are treated in the Intensive Care Unit (ICU) to cause death (W. Guan et al., 2020). COVID-19 patients who are smokers in critical rooms experience Pneumonia and Severe Acute Respiratory Distress Syndrome (ARDS) so that they must use a ventilator in the Intensive Care Unit (ICU) that can even cause death (W. . Another study found that the virus receptor of angiotensin-converting enzyme II (ACE2) is the medium for SARS-CoV 2 entry into the body's cells, and ACE2 expression is significantly higher in smokers than in nonsmokers. Severe and critical cases of COVID-19 are more likely to be in smokers . A study on the effect of active or passive smokers, the number of cigarettes smoked every day, and the period of being a smoker is still unclear. No studies have been performed accurately on CO-VID-19 infection.
Patients with COVID-19 who experience severe disease symptoms and cause death not only occur in smokers but also in patients with comorbidities (W. . History of Chronic diseases that often occur in COVID-19 are hypertension, cerebrovascular disease, hepatitis B infection chronic obstructive pulmonary disease, diabetes, coronary heart disease, cancer, chronic renal disease, and immunodeficiency (Huang et al., 2020; K Liu, et al., 2020). Comorbidities such as cardiovascular and endocrine are the most common causes of COVID-19 patients in China (W. . People who have comorbidities are more susceptible to COVID-19. If already infected with CO-VID-19, chronic disease will get worse so that more patients are treated in the ICU (K Liu et al., 2020b; Z. Wang et al., 2020)Journal of Infection (2020, especially older people with a history of chronic illness with a high risk of respiratory failure and has a worse prognosis (W.  and can lead to death 2019, in Wuhan, China. Information about critically ill patients with SARS-CoV-2 infection is scarce. We aimed to describe the clinical course and outcomes of critically ill patients with SARS-CoV-2 pneumonia. Methods: In this single-centered, retrospective, observational study, we enrolled 52 critically ill adult patients with SARS-CoV-2 pneumonia who were admitted to the intensive care unit (ICU. Comorbidity assessment is an essential component in determining the prognosis of several diseases, especially pneumonia (W.  so that a comprehensive assessment of comorbidities can build risk classification of COVID-19 patients in the hospital (W. . There are no studies on the effects of long periods of chronic disease with COVID-19 infection, drugs or COVID-19 vaccine do not yet exist, so it must prevent transmission of COVID-19 in patients who have a history of comorbidity. COVID-19 is very contagious. Prevention of transmission of COVID-19 such as self-isolation or quarantine, using personal protective equipment such as masks, washing hands with soap or disinfectants, keeping social distance; Preparation of a health system for seriously ill patients who need isolation, oxygen, and ventilators; Clean and disinfect school buildings, classrooms and environmental sanitation, and especially surface areas that are often touched by many people, eat lots of highly nutritious foods or multivitamins, and exercise (Adhikari et al., 2020;Tingbo, 2020;World Health Organization (WHO), 2020).

CONCLUSION
This study showed that having condition of smoking or comorbidities on COVID-19 patients caused critical illness even death. This condition caused them to be cared in the ICU. Also, smoking people were more susceptible to COVID-19 infection, especially in older age. Children were slightly infected with COVID-19 with severe symptoms.