Diabetes burden in the US South Asian community is high, with national and regional data revealing the highest burden of diagnosed diabetes among Asian Indians compared to other Asian groups(13) and compared to non-Hispanic whites.(14–18),(19, 20) Research also indicates that South Asians living in the US have a higher burden of hypertension compared to some other race/ethnic populations.(21, 22) Our study found significant differences in the burden of diagnosed diabetes and hypertension in South Asians receiving care in NYC compared to Atlanta. Specifically, there was a higher burden of diagnosed diabetes in NYC compared to Atlanta (10.7% compared to 6.7% respectively). The burden of diabetes amongst South Asians in NYC and Atlanta reported in our study is lower than that reported in previous research. Prior community health surveys (NYC Community Health Resources and Needs Assessment 2013–2016 and NYC Community Health Survey 2013–2017) demonstrated that Asian Indians in NYC have a tremendous burden of self-reported diabetes (21%).(3) Additionally, the burden of self-reported diabetes diagnoses among South Asians of normal weight (using adjusted-BMI guidelines for Asians) in NYC is more than triple the rates of diabetes among non-Hispanic whites of normal weight (10.2% vs 2.9%, respectively).(23) Furthermore, in a community-based survey of Asian Indians in Atlanta, the self-reported burden of diabetes was 18.3%, nearly four times as high as non-Hispanic whites and twice as high as Hispanics.(24) Among those who reported diabetes, there was a > 3.5 odds of having co-morbid hypertension. This population further had higher burden of stroke (2.77%) compared to whites (2.12%).(25)
Similarly, we found differences in the burden of hypertension between South Asians receiving health care in NYC compared to Atlanta, with those in Atlanta having a higher burden of 24.7% compared to 20.9% in NYC. The burden of hypertension reported in our study is lower than that found in a representative survey of both diagnosed and undiagnosed hypertension in NYC, which found a burden of hypertension in South Asians of 43%.(22)
Nationwide, 21.4% of people with diabetes are undiagnosed.(26) Differential access to care may partially explain the higher burden of diabetes in NYC versus Atlanta, as New York has expanded their Medicaid program to cover all people with household incomes below 133% of the federal poverty level, while Georgia has not. The lower burden of diabetes and hypertension amongst South Asians in our study compared to previous findings could be due to the fact that our data was collected from two large, private hospital systems, which provide patients with more consistent access to healthcare and may therefore make it more likely for patients to receive preventative care. It is interesting to note that there were significant differences in the burden of diabetes and hypertension between South Asians in the two regions of the US and additional research is necessary to assess differences in regional risk factors that could contribute to this disparity. In addition, a considerable number of South Asians in our study (n = 7,184) had a diagnosis of comorbid diabetes and hypertension. Thus, scalable and translatable interventions that promote diabetes management and hypertension control in this population may have significant potential for public health impact and reducing disparities across the US and South Asia.
We acknowledge several limitations. One limitation of this analysis to consider is misclassification error of South Asian origin based on surnames. Prior work has suggested positive predictive values of surname lists ranging from 74%-91% for Indian surnames in the US(6) and 89.3% among South Asians in Canada(7). We conducted sensitivity analyses limiting the sample to those reporting South Asian race/ethnicity in the NYC sample, and diabetes burden was 11.2%, suggesting risk may be underestimated in these analyses. The cross-sectional nature of these analyses preclude us from examining change over time, but they provide an initial snapshot of regional differences in diabetes burden by region from the perspective of two academic health centers. Selection bias is another key limitation of our analyses. Prior work has demonstrated the study sample is more economically privileged compared to NYC as a whole due to the nature of the NYU patient population(10), and the patient population at Emory is also a selected sample. Several other limitations of using EHR data in clinical research have been previously noted,(27–29) such as differences in procedures for documenting care across systems that could contribute to systematic differences in disease estimates across sites. Finally, we were unable to obtain data on potentially informative covariates such as obesity (BMI was frequently missing in the Atlanta data), diet, physical activity, and socioeconomic status, thus limiting the range of analyses we were able to conduct.
Asian Americans currently compose 5% of the US population and approximately 32% of the immigrants entering the country.(30) The US Census Bureau projects that by 2060, the number of Asian Americans nationally will grow to over 39 million, approximately 9.3% of the US population.(31, 32) In NYC, the South Asian community grew by 49% from 2000 to 2010 (216,179 to 323,675, respectively). South Asians also make up the largest Asian American subgroup in the Atlanta metro area. Across South Asian groups, a significant portion of the community live in poverty (ranging from 17% of Asian Indians to 32% of Bangladeshis), have limited English proficiency impacting access to care (ranging from 25% of Asian Indians to 53% of Bangladeshis), and have poor access to culturally appropriate community resources.(33–36)