Table 1. Impact of COVID-19 and Socioeconomic Disparities on Diabetes Management.

Table 1 Impact of COVID-19 and Socioeconomic Disparities on Diabetes Management
Reference	Sample	Purpose	Methods (Design)	Results	Limitations
Khunti et al. [28]	Patients with type 2 diabetes registered in England between 1/1/2018 to 03/31/2019 and were alive on 02/16/2020. Sample size was 2,851,465.	Assess the relationship between glucose-lowering medications and COVID-19 mortality.	Observational cohort study	Minimal increase in COVID-19 mortality is seen in patients taking insulin, alpha-glucosidase inhibitors, and DPP inhibitors compared to other glucose-lowering medications. Difference is thought to be due to increased severity of disease in patients associated with increased risk of mortality.	Study did not account for frailty of the patient as this factor was not provided in the database used for the study. Data is likely confounded by indication for the medications used.
Nguyen et al. [17]	The study examined 159 counties within Georgia. Sample size was 17,286.	Determine the community variables associated with county-level COVID-19 cases, hospitalizations, and mortality.	Secondary data analysis data acquired from the 2020 County Health Rankings, the 2010 US Census, and the Georgia Department of Public Health COVID-19 Data was evaluated via multivariable linear regression models.	Four findings: The percentage of children living in poverty was found as the most significant predictor of COVID-19 rates. The percentage of severe housing problems appeared as another critical predictor associated with a higher risk of COVID-19 cases, hospitalization, and death rates. Regression analysis showed that the percentage of people not proficient in English was a strong positive predictor as well. Georgian counties diabetic prevalence varied from 5.6% to 32.7%, with the majority, 117 out of 159, above 11.4%, putting Georgia at a potentially higher risk for increased COVID-19 hospitalization and death rates.	Four limitations: Some results remained unexplained due to the involvement of multiple sites in collecting and interpreting the data. More work was needed on explaining racial and ethnic variables and how they contributed to COVID-19 cases and mortality. Testing numbers were not reported which limited the study's scope. Finally, data dates back to September 30, 2020 (more data has emerged since).
Campbell-Scherer et al. [14]	Families who worked with cultural brokers during the pandemic from September 21, 2020, through December 31, 2020.	To identify barriers to COVID-19 prevention and treatment among culturally diverse populations in Canada.	Cultural brokering is defined as linking people of differing cultural backgrounds for the purpose of producing positive change and minimizing conflict [14]. The researchers recorded narratives from families who worked with cultural brokers during the pandemic from September 21, 2020, through December 31, 2020. The sample size was small (16 women and 5 men), but they evaluated the narratives and categorized them into several domains.	They found that (1) financial insecurity, job loss, and inconsistent employment were all hampering COVID prevention and management, (2) more cultural brokers are needed in communities to effectively combat COVID, (3) prevention and management were being compromised by misinformation because of language barriers and cultural distance in the way community members receive and understand information, and (4) strong communication networks and solidarity are a strength that could aid in combatting the pandemic.	Small sample size (16 women and 5 men)
Oliva et al. [18]	Twenty Italian regions were studied.	Identify the determinants of population health involved in the cross-regional difference in COVID-19 mortality.	Ecological study utilizing a systemic review of literature	The findings revealed that four predictors explain regional differences in COVID-19 mortality. These predictors are severity of infection, number of elderly living in assisted facilities, population density, and standard rate of diabetes. Predictors could explain over 95% of the differences in cross-regional mortality observed in Italy from the onset of the epidemic to late 2020.	Possible bias from unpublished articles used in the systemic review. Also most models used for COVID-19 were undergoing peer review process when this systemic study began.
Goyal et al. [2]	No study was carried out. The article provided proposed guidelines on how to screen for and treat hyperglycemia in individuals with COVID in low-income settings.	This commentary proposed strategies for screening hyperglycemia in low-resource healthcare settings.	Reviewed guidelines on diabetes and proposed an algorithm based on simple measures of blood glucose (BG) to be implemented by healthcare workers in low-resource settings.	Goyal et al. mention that algorithm may help in early recognition of hyperglycemia and preventions of subsequent complications of COVID-19 [2].	Capillary testing may suffer from inaccuracy, especially at extremes of blood glucose values.
Gutierrez et al. [15]	Individuals tested for SARS-CoV-2 in Mexico	Assess non-communicable diseases, such as diabetes, and socioeconomic status as risk factors for COVID-19 severe outcomes.	Using data from national reporting of SARS-CoV-2 tested individuals in Mexico, they estimated the odds of hospitalization, intubation, and death based on pre-existing non-communicable diseases and socioeconomic indicators.	Obesity, diabetes, and hypertension were associated with increased rates of hospitalization, intubation, and death in individuals diagnosed with COVID-19. The poverty level is also associated with hospitalization and death.	Poverty's association with reduced healthcare access may have underestimated the association between poverty and COVID-19 prognosis.
Saeed et al. [3]	260 Indian residents 30+ years old	To assess and enhance the knowledge, attitudes, and practices that are critical to managing the COVID-19 pandemic successfully, especially in high-risk groups, such as people with hypertension, diabetes, renal/respiratory disorders, etc.	A ​​cross-sectional online survey was carried out among 260 Indian residents 30+ years old. A structured questionnaire was converted into a Google form for online data collection. The questionnaire included collecting data about demographic details of participants, their knowledge about COVID-19, safe practice measurements, their comorbidities, and challenges faced by them in management.	Participants 50 years or older reported difficulty monitoring their health along with difficulty accessing medicine during the COVID-19 pandemic. Participants suffering from multiple comorbid conditions had difficulty accessing healthcare. Accessibility to medicine was significantly associated with the education of the participant. Also, access to lab investigations and medicines was found to be most difficult for diabetic participants.	Study may be limited by voluntary response bias.
Kalyanaraman et al. [19]	No study carried out. Article reviewed the fundamental mechanisms responsible for disparate underlying conditions related to the disproportionate impact of SARS-CoV-2 on ethnic minority groups, focusing on neutrophil extracellular traps (NETs), especially in African American populations.	To understand the hypothetical mechanisms for enhanced vulnerability of African Americans to SARS-CoV-2 infection, COVID-19 severity, and increased deaths.	Review article using a systematic approach to address the fundamental mechanisms responsible for disparate underlying conditions related to the disproportionate impact of SARS-CoV-2 on ethnic minority groups, focusing on neutrophil extracellular traps (NETs).	Elevated levels of NETs are produced in the lungs of COVID-19 patients, leading to hyperinflammation and respiratory failure. NETs can be used as a marker to predict deadly effects caused by COVID-19. Increased NETs are seen in several chronic medical conditions that are more commonly seen in African Americans, such as obesity, hypertension, diabetes, and sickle cell disease, which can increase the severity of COVID-19. The article concluded diabetes is a key risk factor for developing severe COVID-19, and COVID-19 patients with this underlying condition are more likely to die of respiratory and cardiovascular complications.	Mechanism discussed is only hypothetical at the time of the article being written. Conclusions that were drawn only discussed the "potential" of neutrophil extracellular traps putting African American populations at a higher risk of mortality and morbidity of COVID-19.
van der Linden et al. [25]	US users of the G6 rtCGM (real-time continuous glucose monitoring) system who uploaded data before and during COVID-19.	To determine how time in range (TIR) of glucose control was affected during the COVID-19 pandemic.	Data analysis of app data from users of the G6 rtCGM system	The overall average TIR (time in range; i.e. of glucose control) improved by 0.3% during the early pandemic period. Higher COVID-19 mortality was associated with higher proportions of individuals experiencing TIR improvements of >5 percentage points.	Inability to quantify the populations' age distributions, diagnoses, racial/ethnic backgrounds, type of diabetes or comorbidities, medication regimens, or adoption of other diabetes-related technologies.
Selden et al. [20]	Data from MEPS of individuals who fell under CDC health risks for COVID-19, including extreme obesity, current smoker, 65+, diabetes, asthma, emphysema or other COPD, cancer, or coronary heart disease.	To determine the possible explanations for racial and ethnic disparities amongst COVID-19 patients who were hospitalized or died due to COVID-19	Systematic review	COVID-19 outcomes stem from structural racism on many levels, including income, education, health insurance, access to medical care, access to food, and health status.	Only examined the non-institutionalized community, i.e. those individuals who are not in elderly care facilities, correctional facilities, etc. This is a limitation because it is estimated that 42% of all COVID-19 fatalities have occurred among residents of nursing homes and long-term care facilities.
Gao et al. [5]	COVID-19 patients with possible risk factors such as hypertension, diabetes, obesity, chronic lung diseases, heart, liver, and kidney diseases, tumors, clinically apparent immunodeficiencies, local immunodeficiencies, such as early type I interferon secretion capacity, and pregnancy.	To review the current data on a comprehensive list of possible risk factors associated with COVID-19 severity.	Scoping review	Diabetes has been identified as one of the major risk factors of severe clinical course and prognosis of Covid-19 patients.	Some studies in the scoping review address general risk factors of COVID-19 development and others specifically focus on risk factors for severe COVID-19 leaving very little room to assess risk factors' chronological impact on disease severity.
Vahidy et al. [16]	COVID-19 Surveillance and Outcomes Registry in Houston, Texas	To assess the role that race and ethnic disparities play in likelihood of COVID-19 infection and evaluate the pathways that lead to differences in infection rates amongst socioeconomic groups.	Cross-sectional analysis of COVID-19 Surveillance and Outcomes Registry	Racial minorities including Hispanics and non-Hispanic black individuals are almost twice as likely to test positive for SARS-CoV-2 when compared to the non-Hispanic white population.	Does not include diabetic care.
de Souza et al. [27]	Brazilian Ministry of Health Database (SIVEP-Gripe). Sample size was 162,045. Period from February 26th to August 10th, 2020	To create a clinical profile that can be used to assist the decision-making of physicians regarding poor prognosis patients.	Analyze demographic data, clinical symptoms, and comorbidities	Higher hospitalization rate among males and older population, higher lethality among hospitalized patients. Numerous prevalent symptoms were also discovered that included cough and dyspnea.	Short study
Kyazze et al. [22]	COVID-19 patients with diabetes in Africa	To illustrate methods to optimize care in diabetics with COVID-19 in Africa and understand the correlation between DM and negative COVID-related outcomes.	Research studies that outline comorbidities associated with diabetes and COVID-19 and compile their results to create strategies to improve COVID-19 outcomes in these patients	Strong correlation with DM being a factor leading to death in COVID-19 patients	Study only targets one population.
Gopalan et al. [13]	Population belonging to low socioeconomic stratum (SES) in India.	To examine and discuss the impact of the lockdown in response to the COVID-19 pandemic on social, economic, health, and National Health Programs in India.	Literature review	Morbidity and mortality due to COVID-19 in India are largely attributable to co-morbid conditions like diabetes, hypertension, or cardiovascular disease [13]. Based on a prediction model, the duration of lockdown is directly proportional to the worsening of glycemic control in patients with diabetes as well as would increase diabetes-related complications.
Chun et al. [4]	A study group of 10,069 individuals with type 1 and type 2 diabetes utilizing ICD10 codes. The control group of 50,587 individuals were selected with varying ages, gender, and region.	To determine the infection risk of COVID-19 in patients with diabetes.	Utilized population data from the national health information database (2015-2019) in Korea as well as the national health insurance service which maintains all medical information and demographics of the entire Korean population because of their compulsory social insurance system.	The results indicated that diabetics utilizing insulin therapy had a higher risk of contracting COVID-19 than those without diabetes.
Clark et al. [26]	188 countries	To understand the number of individuals at an increased risk of severe COVID-19 and how it varies between countries in order to develop strategies to vaccinate and protect those at the highest risk.	Population data derived from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 and UN population estimates for 2020. Included patients who have at least one condition labeled as cause for severe COVID-19 in current guidelines.	It was estimated that 1.7 billion individuals, comprising 22% of the global population, have at least one underlying condition that could increase their risk of severe COVID-19. The prevalence of one or more conditions was approximately 10% by age 25 years, 33% by 50 years, and 66% by 70 years, and similar for males and females. It was estimated that 23% of the global working-age population (15-64 years) have at least one underlying condition. Chronic kidney disease and diabetes were the most common conditions in this age range.
Glennie et al. [29]	Canadian patients with T1DM and T2DM	To examine the benefits of using advanced glucose monitoring systems.	Systematic review looking at journals from CINAHL, Ovid MEDLINE ALL, Embase, and APA PsycINFO. Used controlled search phrases across databases and excluded animal-only records. Also incorporated survey data from various healthcare systems in Canada.	COVID-19 caused a large shift to virtual medicine in both persons with and without diabetes mellitus. Utilization of advanced glucose monitoring systems has improved remote glycemic control by enabling patients to make more informed decisions about their diabetic regimen and increasing awareness of how certain factors directly affect their glucose level. Overall, use of these monitors enabled better self-management of blood glucose. These systems can also be used to send data digitally.