Favorable outcomes of elderly COVID-19 patients in Guangzhou, China: a retrospective, observational study

Objective: To clarify the outcomes of elderly patients with COVID-19. Methods: All 265 confirmed adult patients with COVID-19 were included in this retrospective study, 43 (16.2%) of whom were 65 years and older. Electronic medical records of the subjects were reviewed to obtain information on clinical characteristics and outcomes. The allocations of medical resource were also recorded. Results: Only one death case occurred in the elderly. The mortality of elderly patients was no higher than that of young patients (2.3% vs. 0%, P = 0.126). The cure rate was 95.3% in elderly patients and 99.5% in young patients ( P = 0.067), and the duration of hospitalization is 27 days in elderly patients and 18 days in young patients ( P = 0.001). The elderly suffered from more comorbidities (67.4% vs. 24.8%, P < 0.001), most of which is hypertension. Significantly more severe cases occurred in elderly patients compared with young patients (37.2% vs. 16.7%, P = 0.004). The elderly were more likely to present with complications including acute respiratory distress syndrome, acute myocardial injury, septic shock and acute kidney injury (all P < 0.05), respectively. No medical staffs were infected during the treatment of COVID-19. Conclusion: The cure rate and the mortality of the elderly seemed to be no worse than that of the young, though the elderly were with longer hospitalization. Elderly patients with COVID-19 could be treatable if handled properly. More severe cases and complications in elderly patients should prompt for more complex treatment and special considerations.


Introduction
COVID-19 is a respiratory infectious disease caused by a novel betacoronavirus, with typical symptoms such as fever, cough, sore throat, among others [1,2]. In December 2019, a COVID-19 epidemic broke out in China and swept over the world within months later [3][4][5]. Given that general population is susceptible to the virus, affected victims has been increasing in number. As of May 2, there are more than 3,000,000 cases of COVID-19 infection in about 200 countries and regions, leading to a death toll of about 200,000, with devastating impacts on the public health, economy, and social security globally [5].
Owing to age related comorbidities, declined airway protection and slow immune responses, the elderly are more susceptible to COVID-19 and with higher morbidity and mortality [3,6,7]. Actually, the mortality in elderly patients varies from 0 to 34.5% in different region [8][9][10][11], and there have been less studies focusing on outcomes of elderly patients, among whom a general picture of the disease remains inadequately investigated.
In this retrospective study, we sought to describe the outcomes of COVID-19 infection in the elderly, and to share and analysis the strategies helpful to improve prognosis. We expected that understanding the outcomes of COVID-19 in these patients subset would be of great sense in guiding treatment, and preventing spread of the disease in a wider range.

Methods
This was a single-center, retrospective, observational study recruiting all consecutive adult patients with COVID-19 infection treated between January 20 to February 14, 2020, in Guangzhou Eighth People's Hospital, a government-designated hospital which admitted nearly 80% of the COVID-19 cases in Guangzhou, the capital city of Guangdong Province in southern China. The COVID-19 was diagnosed as per the World Health Organization interim guidelines [12]. Elderly patients referred to those aged 65 years or older. Accordingly, an age below 65 years was defined as 'young' patients in this study. The present study was approved by the Ethics Committee of Guangzhou Eighth People's Hospital (202001134). Because of the retrospective nature of the study design and the grim scenario of COVID-19 epidemic, the Ethics Committee assented to exempt of all informed consents after protection of patient identification and privacy was guaranteed by the study team.
Electronic medical records of the subjects were reviewed to obtain information on demography, symptoms, medical history, epidemiological history, laboratory findings, imaging studies, complications, treatments, and outcomes. The outcomes included mortality rate, cure rate and duration of hospitalization. The outcomes were fixed to March 20, 2020, the final date of follow-up.
The allocations of medical resource were also recorded. The data collection was completed independently by a collaboration team of physicians from Guangzhou First People's Hospital.
A confirmed case with COVID-19 was defined as a positive result to real-time reverse transcriptase polymerase chain reaction (RT-PCR) assay or highthroughput sequencing for nasal or pharyngeal swabs [12]. Severe COVID-19 was defined according to the criteria for community-acquired pneumonia (CAP) [13]. Acute liver injury was defined according to the European Association for the Study of the Liver's guideline [14]. Septic shock was defined in accordance with the Surviving Sepsis Campaign's guidance [15]. Acute respiratory distress syndrome (ARDS) was defined in accordance with the Berlin definition [16]. Acute kidney injury was identified according to the Kidney Disease: Improving Global Outcomes definition [17]. Acute Cardiac injury followed the definition used in previous study in patients with H7N9 [18]. The discharge standard was as followed: Be stable for more than 3 days; there was a negative result to RT-PCR assay in two consecutive times, 24 hours apart; the focus of chest CT were absorbed or cured. All patients who met discharge criteria were reviewed by 2 senior physicians.
Shapiro-Wilk normality test was used to assess for normal distribution of the data. Continuous variables with normal distribution are expressed as mean ± standard deviations (SD) while those with non-normal distribution as median and inter quartile range (IQR). Categorical variables are summarized as counts and percentages. For continuous variables, independent t-test or Wilcoxon rank sum test were used. For comparison of categorical variables, Chi-square test and Fisher's exact test were used. All data were processed with SPSS version 22.0 for Windows (SPSS, Chicago, IL, USA).

Baseline Characteristics
All confirmed adult patients were admitted to this study. There were 265 adult patients with COVID-19, with 43 (16.2%) aged 65 years and older. The baseline characteristics were shown in Table 1.
Compared with young patients, elderly patients were more likely to have at least one comorbidity (67.4% vs. 24.8%, P < 0.001), most of which was hypertension (41.9% vs. 16.2%, P < 0.001). Severe cases were more common in elderly patients as compared with the young (37.2% vs. 16.7%, P = 0.004). The median incubation period was 5 days for either elderly patients or young patients. There were no differences in incubation period between elderly and young patients (P = 0.913). The median time from diagnosis to hospitalization was -1 day for either elderly patients or young patients, and no differences were found between the two groups (P = 0.749). Fever was the most common symptom, found in a total of 182 patients comprising 31 elderly and 151 young patients (72.1% vs. 68.0%, P = 0.720). A total of 142 patients including 25 elderly and 117 young patients complained of coughs (58.1% vs. 52.7%, P = 0.617). Other symptoms included pharyngalgia, expectoration, and chills.
Overall, there were no significant differences in symptoms between the elderly and young patients.

Imaging and Laboratory findings
The radiologic and laboratory findings were shown in Table 2. Compared with the young, the elderly patients showed lower serum albumin (35.9 vs. 39.8 g/L, P < 0.001), higher serum creatinine (58.3 vs. 28.2 μmol/L, P = 0.011) and urea nitrogen levels (4.8 vs. 3.6 mmol/L, P < 0.001). There were no significant differences between the two age groups in white blood cell counts, neutrophils,

Outcomes
The clinical outcomes were shown in Table 4. One death case occurred in the elderly. The mortality of elderly patients was no higher than that of young patients (2.3% vs. 0%, P = 0.126). One patient in each group was transferred to another hospital. As of March 20, 41 elderly patients and 220 young patients had been discharged home (95.3% VS. 99.5%, P = 0.067), and the duration of hospitalization is 27.0 days in elderly patients and 18.0 days in young patients (P = 0.001).

Medical resource
A total of about 200 doctors and 600 nurses participated in the treatment of COVID-19 (Table 5). The average daily consumption of N95 mask is 2 per person, and about 1.5 protective suits were consumed per person per day. No medical staffs were infected during the treatment of COVID-19.

Discussion
This work shed light on the outcomes of elderly patients with COVID-19, with comparison to young individuals in southern China, and analyzed the role of medical resources in the disease prevention and control for the first time. Although the elderly spent more time in hospitalization, the cure rate and the mortality of the elderly seemed to be no worse than that of the young.
A possible reason for these favorable outcomes is early diagnosis, isolation and treatment for all patients [4], and these strategies need to be supported by sufficient medical resources. In this study, Centers for Disease Control recorded the activity track of all patients, screened and followed up the persons who contacted with them. For every suspected COVID-19 case, testing was performed without any hesitation. The median time from diagnosis to hospitalization is about -1 day, which means that each confirmed patient was isolated and treated in hospital immediately, and high suspected subjects were admitted to hospital before diagnosis. Of note, some patients were asymptomatic and merely with abnormal imaging signs. Such clinical silence could partially undermine the containment of COVID-19, due to missed diagnosis, misdiagnosis and treatment delay. others, it remains controversial to decide when to start using antibiotics. Respiratory viruses play crucial roles in triggering bacterial attack, and older individuals are more susceptible to bacterial attack due to low immunity and high risk of aspiration [6,21]. Therefore, early identification and management of bacterial infections is the key to improving prognosis. According to guidelines for treatment of community-acquired pneumonia guidelines, patients with influenza-positive CAP should be treated with antibiotics as soon as possible [13]; however, for pneumonia caused by COVID-19, how to identify bacterial infections and when to start antibiotics are yet to be clarified. Given the serious morbidity and mortality of COVID-19, patients with suspected bacterial infection should be prescribed antibiotics after weighing the advantages and disadvantages. Further search is needed to assess the effect of antibiotics in the treatment of COVID-19.
This study showed limitations in several aspects. First, due to retrospective nature of the study, certain clinical data such as body mass index (BMI), smoking history and infection history in the previous year were missing, and this would affect precise interpretation of the study results. Second, with a cross-sectional design, this study did not include a sample size sufficiently large to enable determining the risk factors of mortality in older patients. Third, as an observational study, it is unable to assess the effectiveness of these interventions in this study. Finally, this was a single-center study on COVID-19 patients from southern China. Therefore, our findings should be interpreted with caution and may not be suitable for generalization in a wider population.

Conclusions
The cure rate and the mortality of the elderly seemed to be no worse than that of the young, though the elderly were with longer hospitalization. Elderly patients with COVID-19 could be treatable if supported by sufficient medical resources. More severe cases and complications in elderly patients should prompt for more complex treatment and special considerations.