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The country of Spain has one of the highest incidences of COVID-19, with more than 1,000,000 cases as of the end of October 2020. Patients with a history of chronic conditions, obesity, and cancer are at greater risk from COVID-19; moreover, concerns surrounding the use of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin type II receptor blockers (ARBs) and its relationship to COVID-19 susceptibility have increased since the beginning of the pandemic.
The objectives of this study were to compare the characteristics of patients diagnosed with COVID-19 to those of patients without COVID-19 in primary care; to determine the risk factors associated with the outcome of mortality; and to determine the potential influence of certain medications, such as ACEIs and ARBs, on the mortality of patients with COVID-19.
An observational retrospective study of patients diagnosed with COVID-19 in the Catalan Central Region of Spain between March 1 and August 17, 2020, was conducted. The data were obtained from the Primary Care Services Information Technologies System of the Catalan Institute of Health in Barcelona, Spain.
The study population included 348,596 patients (aged >15 years) registered in the Primary Care Services Information Technologies System of the Catalan Central Region. The mean age of the patients was 49.53 years (SD 19.42), and 31.17% of the patients were aged ≥60 years. 175,484/348,596 patients (50.34%) were women. A total of 23,844/348,596 patients (6.84%) in the population studied were diagnosed with COVID-19 during the study period, and the most common clinical conditions of these patients were hypertension (5267 patients, 22.1%) and obesity (5181 patients, 21.7%). Overall, 2680/348,596 patients in the study population (0.77%) died during the study period. The number of deaths among patients without COVID-19 was 1825/324,752 (0.56%; mean age 80.6 years, SD 13.3), while among patients diagnosed with COVID-19, the number of deaths was 855/23,844 (3.58%; mean age 83.0 years, SD 10.80) with an OR of 6.58 (95% CI 6.06-7.15).
We observed that women were more likely to contract COVID-19 than men. In addition, our study did not show that hypertension, obesity, or being treated with ACEIs or ARBs was linked to an increase in mortality in patients with COVID-19. Age is the main factor associated with mortality in patients infected with SARS-CoV-2.
A highly pathogenic coronavirus, SARS-CoV-2, was first described in Wuhan in late December 2019 and has since spread worldwide [
Since the beginning of the pandemic, it has been clearly shown that COVID-19 disproportionately affects patients with a history of chronic conditions such as cardiovascular disease, chronic obstructive pulmonary disease (COPD), hypertension, and diabetes mellitus [
Although angiotensin-converting enzyme (ACE) and ACE2 are distinct enzymes with different mechanisms of action [
Although the burden of managing the COVID-19 pandemic initially fell on hospitals, this situation has gradually changed; primary care services are handling more cases, which is requiring substantial changes in the way primary care services are delivered to populations to manage the COVID-19 pandemic [
The objectives of this study were (1) to compare the characteristics of adult patients diagnosed with COVID-19 compared to patients without COVID-19 in primary care; (2) to determine the risk factors for these patients associated with fatality as the outcome; and (3) to analyze the influence of taking medications such as ACEIs and ARBs on the mortality of patients with COVID-19.
An observational retrospective study was conducted on patients diagnosed with COVID-19 living in Spain, specifically in the Catalan Central Region, from March 1 to August 17, 2020. The population in the region over the age of 15 years was included in the study, with 348,596 patients. Patients older than 15 years are cared for by family and community specialists in primary care in Spain. The population of the area, including patients younger than 16 years, was 415,000 at the time of the study. Among the patients included in the study, 6.8% (23,844/348,596) had been diagnosed with COVID-19.
The data were extracted from the computerized medical records of the Primary Care Services Information Technologies (IT) System of the Catalan Institute of Health in Barcelona, Spain. The Primary Care Services IT System contains primary care electronic health records (EHRs) for over 6 million people in Catalonia, covering more than 80% of the Catalan population [
The study protocol was approved by the University Institute for Primary Care Research Jordi Gol Health Care Ethics Committee (Code 20/066-PCV).
Categorical variables are described using frequencies and percentages. Continuous variables are described with means and standard deviation. Proportions of categorical variables were compared using the Fisher exact test, and the sample
The study population included 348,596 patients over 15 years of age registered in the Primary Care Services IT System of the Central Catalan Region in Spain. The mean age of the patients was 49.53 years (SD 19.4), and 108,762/348,596 (31.2%) of the patients were aged ≥60 years. Overall, 175,484/348,596 patients (50.3%) were female. The most common comorbidities and clinical conditions were hypertension (75,699/348,596, 21.7%), dyslipidemia (71,424/348,596, 20.5%), and obesity (69,501/348,596, 19.9%). Regarding patients with hypertension, 22,771/75,699 (30.1%) of them were being treated with ACEIs and 9487/75,699 (12.5%) were being treated with ARBs. A comparison of the demographics and risk factors of patients without COVID-19 and patients diagnosed with COVID-19 is shown in
The characteristics of patients with and without COVID-19 are shown in
Patients who had been diagnosed with COVID-19 were more likely to have diverse comorbidities. Diabetes (
Demographics and comorbidities of the study population, including patients with and without COVID-19 (N=348,596). Multivariate analysis of the risk factors was performed. Age was adjusted for sex and sex was adjusted for age. The remaining risk factors were adjusted for age and sex.
Demographics and risk factors | Patients with COVID-19 (n=23,844) | Patients without COVID-19 (n=324,752) | Adjusted odds ratio (95% CI) | |||||
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Age (years), mean (SD) | 49.93 (19.4) | 49.53 (20.0) | 1.0 (0.99-1.0) | .10 | |||
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N/Aa | <.001 | |||||
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16-30 | 4239 (19.2) | 61,382 (20.4) |
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31-40 | 4182 (18.9) | 49,610 (16.5) |
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41-50 | 4381 (19.8) | 56,457 (18.7) |
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51-60 | 3685 (16.6) | 48,309 (16.0) |
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61-70 | 1841 (8.3) | 39,163 (13.0) |
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71-80 | 1335 (6.0) | 25,999 (8.6) |
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81-90 | 1763 (8.0) | 16,884 (5.6) |
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>90 | 739 (3.3) | 3620 (1.2) |
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0.73 (0.71-0.75) | <.001 | |||||
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Female | 13,763 (57.7) | 161,721 (49.8) |
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Male | 10,081 (42.3) | 163,031 (51.2) |
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Hypertension | 5267 (22.1) | 70,432 (21.7) | 1.01 (0.97-1.04) | .77 | |||
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Diabetes | 2101 (8.8) | 27,379 (8.4) | 1.06 (1.01-1.12) | .01 | |||
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Dyslipidemia | 4749 (19.9) | 66,675 (20.5) | 0.94 (0.90-0.97) | <.001 | |||
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Obesity | 5181 (21.7) | 64,320 (19.8) | 1.10 (1.06-1.14) | <.001 | |||
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Chronic obstructive pulmonary disease | 685 (2.9) | 8193 (2.5) | 1.23 (1.14-1.34) | .001 | |||
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Cancer | 1765 (7.4) | 21,785 (6.7) | 1.09 (1.04-1.15) | <.001 | |||
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Current smoker | 3578 (15.0) | 46,659 (14.3) | 1.09 (1.05-1.13) | <.001 | |||
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Heart failure | 515 (2.2) | 4301 (1.3) | 1.63 (1.48-1.79) | <.001 | |||
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Cerebrovascular disease | 176 (0.7) | 1658 (0.5) | 1.48 (1.26-1.72) | <.001 | |||
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Ischemic heart disease | 627 (2.6) | 8122 (2.5) | 1.11 (1.02-1.20) | .02 |
aN/A: not applicable.
A total of 2680/348,596 patients (0.77%) in the overall study population died during the study period. The number of deaths among patients without COVID-19 was 1825/324,752 (0.56%); meanwhile, the number of deaths among patients diagnosed with COVID-19 was 855 (3.72%), with an odds ratio (OR) of 6.58 (
The frequency of risk factors and the statistical analysis of the association of the different risk factors with mortality adjusted for age and sex among patients diagnosed with COVID-19 are shown in
Characteristics of deceased and living patients diagnosed with COVID-19.
Demographics and risk factors | Deceased patients with COVID-19 (n=855) | Living patients with COVID-19 (n=22,989) | Adjusted odds ratio (95% CI) | |||||||||
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Age (years), mean (SD) | 83 (10.8) | 48.7 (19.2) | 1.12 (1.11-1.13) | <.001 | |||||||
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2.22 (1.90-2.60) | <.001 | |||||||||
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Male |
468 (54.7) | 13,295 (57.8) |
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Female | 387 (45.3) | 9694 (42.2) |
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Hypertension | 587 (68.7) | 4680 (20.4) | 1.16 (0.98-1.37) | .09 | |||||||
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Diabetes | 278 (32.5) | 1823 (7.9) | 1.69 (1.43-1.99) | <.001 | |||||||
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Dyslipidemia | 383 (44.7) | 4367 (19.0) | 1.19 (1.03-1.39) | .03 | |||||||
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Obesity | 250 (29.2) | 4931 (21.5) | 1.08 (0.91-1.27) | .38 | |||||||
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Chronic obstructive pulmonary disease | |||||||||||
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Cancer | 210 (24.6) | 1555 (6.8) | 1.19 (0.99-1.43) | .06 | |||||||
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Current smoker | 37 (4.3) | 3541 (15.4) | 0.98 (0.67-1.39) | .93 | |||||||
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Heart failure | 127 (14.9) | 388 (1.7) | 1.59 (1.26-1.99) | <.001 | |||||||
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Cerebrovascular disease | 21 (2.5) | 155 (0.7) | 0.84 (0.50-1.33) | .47 | |||||||
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Ischemic heart disease | 93 (10.9) | 534 (2.3) | 1.20 (0.93-1.54) | .15 | |||||||
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Treatment with ACEIsb | 152 (17.8) | 1549 (6.7) | 0.90 (0.74-1.09) | .32 | |||||||
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Treatment with ARBsc | 75 (8.8) | 654 (2.8) | 1.00 (0.76-1.30) | .98 |
aIn the multivariate analysis, sex was adjusted for age and age was adjusted for sex. The remaining risk factors were adjusted for age and sex.
bACEIs: angiotensin-converting-enzyme inhibitors.
cARBs: angiotensin II receptor blockers.
The logistic regression analysis showed that several conditions, such as diabetes, dyslipidemia, and heart failure, were associated with increased death risk with significant differences. Age and (male) sex were also associated with an increased death risk, with significant differences. Meanwhile, hypertension, obesity, COPD, cancer, being a current smoker, cerebrovascular disease, and ischemic heart disease did not show an increased risk of mortality among patients diagnosed with COVID-19.
Risk factors associated with mortality in patients with COVID-19. The associations of each risk factor were estimated using logistic regression models adjusted for age and sex; sex was adjusted for age, and age was adjusted for sex. ACEIs: angiotensin-converting enzyme inhibitors; ARBs: angiotensin II receptor blockers; COPD: chronic obstructive pulmonary disease.
We report the clinical characteristics and mortality rates of 23,844 patients diagnosed with COVID-19 in primary care, who constituted 6.84% of the population studied in the Central Catalan Region aged ≥16 years. This is one of only a few larger studies of COVID-19 patients conducted in primary care settings [
In our study, we report lower rates of comorbidity among patients diagnosed with COVID-19 compared to another study carried out in Catalonia in primary care, with rates of 33.9% for hypertension, 14.3% for diabetes, 5.9% for COPD, and 11.5% for cancer. In contrast, they reported lower rates of dyslipidemia (13.7%) and obesity (14.3%) [
Numerous studies have shown that male sex and older age are associated with higher COVID-19–related mortality, a conclusion which our study strongly supports [
In our study, diabetes was more common in patients with COVID-19 and was associated with an increased risk of death. This finding is in accordance with a meta-analysis that analyzed the association between comorbid diabetes and disease severity or death [
As for smoking, we found that smokers were more frequently infected with COVID-19, although with no increased risk of mortality. Regarding risk factors such as cancer and cerebrovascular disease, patients diagnosed with COVID-19 were not at a higher risk of mortality. In addition, our results are in keeping with those showing that ACEIs and ARBs are not significantly associated with an increased risk of death among patients with COVID-19 [
The study has several limitations. The diagnostics of COVID-19 registered in the Primary Care Services IT System during the early months of the pandemic were based on both clinical and polymerase chain reaction (PCR) testing. This is a pragmatic approach due to the fact that PCR testing was not fully available in primary care during the first few weeks of the pandemic. After the first months of pandemic the number of PCR tests performed increased, and for this reason the number of COVID-19 diagnoses may be underestimated during the period of our study. Although we included the majority of relevant risk factors and comorbidities associated with COVID-19 in the study, additional conditions should be considered, which may have an impact on the analysis and its interpretation. Although the coverage of patients followed up by primary care physicians is approximately 80% of the population in Catalonia, including this health care area studied, it is unlikely but possible that the remaining 20% of patients have other demographic or health characteristics that could affect the results. In addition, as can occur in other diseases, the registration and mortality of cases can be underestimated or can be affected by factors such as gender; this may modify some of the results presented.
At the beginning of the COVID-19 outbreak, attention was focused on the characteristics of patients diagnosed with COVID-19 who were admitted to hospital. However, after the period of our study, the attention shifted to community and primary care services, coinciding with the work overload in primary care settings and the possibility of more extensive SARS-CoV-2 testing. Our study is focused on patients in primary care with COVID-19, unlike most previous studies on COVID-19, which are based on hospital data. As we observed in our study, hypertension, one of the risk factors associated with COVID-19, was neither more frequent nor associated with higher mortality in patients with COVID-19 in primary care. We observed that women were more affected by COVID-19, unlike the majority of studies, which reported that men more frequently contracted the disease. In addition, our study did not find an associated risk between obesity and COVID-19, another risk factor associated with increased COVID-19–related mortality. Furthermore, treatment with ACEIs or ARBs was not associated with a higher mortality rate among patients infected with SARS-CoV-2. Age was the most important factor associated with mortality in patients with COVID-19.
Further studies focused on community and primary care are needed to provide new insights into SARS-CoV-2 infection and how to address outbreaks and improve health care strategies in pandemic situations.
Full list of diagnosis codes used in the study.
angiotensin-converting enzyme
angiotensin-converting enzyme II
angiotensin-converting enzyme inhibitor
angiotensin type II receptor blocker
chronic obstructive pulmonary disease
electronic health record
International Statistical Classification of Diseases and Related Health Problems 10th Edition
information technology
odds ratio
polymerase chain reaction
World Health Organization
We are grateful to the staff at the Technical and Support Area of
None declared.