Global prevalence and effect of comorbidities and smoking status on severity and mortality of COVID-19 in association with age and gender: a systematic review, meta-analysis and meta-regression

Abstract

A COVID-19 patient often presents with multiple comorbidities and is associated with adverse outcomes. A comprehensive assessment of the prevalence of comorbidities in patients with COVID-19 is essential. This study aimed to assess the prevalence of comorbidities, severity and mortality with regard to geographic region, age, gender and smoking status in patients with COVID-19. A systematic review and multistage meta-analyses were reported using PRISMA guidelines. PubMed/MEDLINE, SCOPUS, Google Scholar and EMBASE were searched from January 2020 to October 2022. Cross-sectional studies, cohort studies, case series studies, and case–control studies on comorbidities reporting among the COVID-19 populations that were published in English were included. The pooled prevalence of various medical conditions in COVID-19 patients was calculated based on regional population size weights. Stratified analyses were performed to understand the variations in the medical conditions based on age, gender, and geographic region. A total of 190 studies comprising 105 million COVID-19 patients were included. Statistical analyses were performed using STATA software, version 16 MP (StataCorp, College Station, TX). Meta-analysis of proportion was performed to obtain pooled values of the prevalence of medical comorbidities: hypertension (39%, 95% CI 36–42, n = 170 studies), obesity (27%, 95% CI 25–30%, n = 169 studies), diabetes (27%, 95% CI 25–30%, n = 175), and asthma (8%, 95% CI 7–9%, n = 112). Moreover, the prevalence of hospitalization was 35% (95% CI 29–41%, n = 61), intensive care admissions 17% (95% CI 14–21, n = 106), and mortality 18% (95% CI 16–21%, n = 145). The prevalence of hypertension was highest in Europe at 44% (95% CI 39–47%, n = 68), obesity and diabetes at 30% (95% CI, 26–34, n = 79) and 27% (95%CI, 24–30, n = 80) in North America, and asthma in Europe at 9% (95% CI 8–11, n = 41). Obesity was high among the ≥ 50 years (30%, n = 112) age group, diabetes among Men (26%, n = 124) and observational studies reported higher mortality than case–control studies (19% vs. 14%). Random effects meta-regression found a significant association between age and diabetes (p < 0.001), hypertension (p < 0.001), asthma (p < 0.05), ICU admission (p < 0.05) and mortality (p < 0.001). Overall, a higher global prevalence of hypertension (39%) and a lower prevalence of asthma (8%), and 18% of mortality were found in patients with COVID-19. Hence, geographical regions with respective chronic medical comorbidities should accelerate regular booster dose vaccination, preferably to those patients with chronic comorbidities, to prevent and lower the severity and mortality of COVID-19 disease with novel SARS-CoV-2 variants of concern (VOC).

Impact and prevalence of comorbidities and complications on the severity of COVID-19 in association with age, gender, obesity, and pre-existing smoking: A meta-analysis

“…These risk factors increase the risk of admission to intensive care units, and could be life-threatening [ 49 , 51 , 52 ]. In contrast to some studies, our study reported several comorbidities [ 47 , 52 – 54 ]. Interestingly, previous studies such as that of Ross Arena and his colleagues have indicated that unhealthy lifestyle behaviors, comorbidities, and COVID-19 syndemic in severe cases raise the question of a complex interaction of health factors, acting synergistically to worsen the overall consequences of the disease [ 4 – 6 ].…”

“…The different risk factors reported in this meta-analysis are predictive of a severe and critical form of the disease, requiring patients’ admission to intensive care units (ICU). Our analysis has shown that the association between age, gender (male), obesity, and smoking status appeared with numerous comorbidities as risk factors for severe COVID-19 [ 47 , 48 ]. Indeed, several studies have reported that advanced age is associated with the severity of COVID-19, primarily due to physiological changes accompanying aging, a weakened immune system and underlying health issues [ 7 , 49 , 50 ].…”

Comparison of time to negative conversion of SARS-CoV-2 between young and elderly among asymptomatic and mild COVID-19 patients: a cohort study from a national containment center

“…Regarding comorbidities, patients in the elderly group were more likely to have past medical history especially hypertension and diabetes which was a common finding in most studies dealing with the same topic ( 1 , 22 ).…”

Marine Sponge-Derived Secondary Metabolites Modulate SARS-CoV-2 Entry Mechanisms

“…In severe cases, the treatment options are still limited, and the emergence of new virus variants makes it even more difficult to develop new therapies. The occurrence of co-factors, including sex [3], age [4], and comorbidities [5], significantly affects the course of the disease and also influences the therapeutic response. Novel therapeutic approaches are therefore needed to better manage viral infections such as COVID- 19.…”