Comorbidities, including obesity, cardiovascular diseases, hypertension, diabetes, chronic kidney disease, and neoplasia contributed significantly to ICU admission or death in hospitalized patients with confirmed COVID-19. Having two or more comorbidities concomitantly increased the risk of ICU admission by 57% and to death by 31% compared with those without comorbidities. Male sex, older age, and comorbidities have consistently shown a higher risk of mortality, but we also found that the hospital care network contributed to adverse outcomes.
The relationship between underlying diseases and the severity of COVID-19 is explained by different pathophysiology mechanisms. It has been stated the influence of inflammatory processes with the accumulation of immune response cells in metabolic tissues(19, 20), the deterioration of lymphocyte and macrophage function(21), the renin-angiotensin-aldosterone system imbalance(22), and more recently, processes of hyper-inflammation and detrimental immunothrombosis(23). Therefore, people with chronic conditions must take extra precautions to avoid COVID-19 infection.
The results of this study are similar to those published in China(24), the United States(25, 26), Spain(15), and Mexico(27). In China(24) the most prevalent underlying diseases in hospitalized patients were hypertension (16.4%), cardiovascular diseases (12.1%), and diabetes (7.9%). In the United States(25), instead, the proportion was higher, for hypertension (63.7%) and diabetes (38.4%). In comparison, our results, the most prevalent comorbidities were hypertension 24.8%, diabetes 19.3%, and obesity 12.5%. By the number of comorbidities, our proportions of the groups with one comorbidity and with two or more comorbidities are similar to those reported in Mexico, 26.0% and 19.3%, respectively.
In Peru, non-communicable diseases such as neoplasm, cardiovascular diseases, diabetes, and chronic kidney disease rank at the top causes of death and contributed significantly to the burden of disease(31). Even though the different efforts implementing policies for the management of chronic diseases such as the “Plan Esperanza” for cancer(32) or the HEARTS initiative for cardiovascular diseases(33), Peru has challenges to accomplish health international goals(34). The individual itself and the health system share responsibilities for the poor control of chronic diseases. On the individual’s side, there is low awareness, adherence to treatment, and control(35). On the health system’s side, we found low political commitment, insufficient financial and human resources, as well as, barriers to access to medicine and regular appointments(36). Although in our study we did not have information about the status of treatment or control of chronic diseases to associate them with worse prognosis, it is known that patients with uncontrolled hypertension or cardiovascular diseases may induce more complications in patients with COVID-19(37).
4.1. Relevance on public health
The first cases of COVID-19 in Peru were reported in March after four months of the first cases in China. During January and February, the WHO warned countries must be prepared for a possible pandemic(38). Peru could not be prepared timely because of past and recent health decisions of government and stakeholders, and the high mortality rate had a significant component of disobedience of restrictions by the population(39). As describe above different measures are taken to face COVID-19 but more efforts are needed for vulnerable people as the elderly or with comorbidities. Many health resources including personnel, infrastructure, medicines, and budgets have been centralized on COVID-19 neglecting healthcare for people with underlying diseases. People with chronic diseases need access to treatments for proper control of their condition, the lack of attention and provision of medicines generates complications that can predispose to worse endpoints if they also acquire COVID-19. The COVID-19 pandemic will continue to be a problem in countries and until an effective cure or safe vaccine is found, it is a function of the health system to take decisions under their control and drive preventive actions tackling underlying disease instead of just COVID-19 management.
4.2. Limitations
We recognized some limitations of this study; our study design only allows describing risk factors related to comorbidities and ICU admission or mortality and serves to identify populations and characteristics that predispose to negative prognosis, we cannot establish causality. The results of this study cannot be generalized to the entire population with confirmed COVID-19 since the results only correspond to hospitalized patients. Even though electronic health records have information about clinical variables at admission, we did not include them in our result because of important proportions of missing; weight (66.9%), blood pressure (60%), body temperature (65%), oxygen saturation (96%), heart rate (51%), and breath rate (61.4%). Those missing may indicate lack of measurement or lack of report due to scarcity of human resources or high demand of patients, either way, it is important not to neglect these measurements because they may help to proper diagnosis and treatment. In some cases, the errors in patients’ evaluation at admission may be differential by severity, where patients with obvious warning symptoms and signs were considered with a life-threatening illness, avoiding clinical measures, but providing prompt healthcare. We stratified patient’s characteristics by severity and adjusted Cox regression by this variable.
On the other hand, the main strength of this study is the inclusion of nationwide data that convey a wider picture concerning patients affiliated with Peruvian Social Health Insurance. Another important strength is we defined comorbidities based on the International Classification of Diseases at any point of the hospitalization, which provides a more reliable identification of the disease and reduces the risk of underestimation caused by self-report. In addition to that, we have a follow-up period that best describes the impact of COVID-19 at the beginning of the pandemic in Peru.