Table 1 Study characteristics.

1

Alperet, 2016 [37]

Chinese, Malay, Asian-Indians

Total: 14,815.

Chinese: 9012

Malay: 3130

Asian-Indians: 2,673

Chinese: 481 (5.34%)

Malay: 299 (9.55%)

Asian-Indians: 239 (8.94%)

Data from Singapore national Health Surveys conducted in 1992, 1998, 2004 and 2010 years (Singapore)

,Individuals aged 18–69 years (men and women).

Median age - 38 years, 46.9%—males.

Median age at T2D diagnosis, (IQR) for UDM: 49, (42–59)

–

BMI, WC, WHR, WHTR (adjusted for age and sex)

WHO criteria for UDM: FPG levels of ≥7.0 mmol/L or a 2-h post-load glucose level of ≥11.1 mmol/L

2

De Koning, 2010 [36]

Aboriginal, African, South Asian, European, Latin American

Total: 22,293

Aboriginal: 12.1% (2697), African: 6.5% (1458), South Asian: 20.3% (4,535), European: 52.9% (11,795), Latin American: 8.1% (1808)

Total: 14% (3112)

Aboriginal: 9.9% (267), African: 18.2% (265), South Asian: 14.1% (640), European: 14.5% (1712), Latin American: 12.6% (228).

The EpiDREAM cohort from the DREAM trial - a large, international, multi-centre, randomised and double-blind controlled trial (international cohort (21 countries))

60% women, 40% men. Mean age was 52.2 (11.4). 44.3% (9861) were smokers. 28.5% (5054) were post-menopausal women.

Mean age of T2D diagnosis: Aboriginals: 52.0 (11.6), Africans: 53.9 (11.0), South Asians: 44.7 (9.2), Europeans: 55.1 (10.8), Latin Americans: 51.3 (11.4)

–

BMI, HC, BMI + WC, BMI + WHR

FPG ≥ 7.0 mmol/l (126 mg/dl) or a 2 h glucose

≥ 11.1 mmol/l (200 mg/dl)

3

Hardy 2017 [31]

Black and White American

Total: 15,242

Black Americans: 3986, White Americans: 11,256

Total: 1827 (12.0%)

Black Americans: 805 (20.2%). Males 18.7%, Females 21.1%.

White Americans: 1022 (9.1%)

Males 10.2%, Females 8.1%.

ARIC study baseline data (1987–89) was used (USA)

Men and women aged 45–65 years

–

ABSI, BAI, BMI, WC, WHTR, WHR (adjusted for age, physical activity and FHD)

ADA criteria: FPG ≥ 126 mg/dL, non-FBG ≥ 200 mg/dL, self-report of diabetes diagnosis, or self-report of taking diabetes medications

4

Meeks, 2015 [32]

Ghanian, African Surinamese, Dutch

Total: 6213

Ghanaian (1873), African Surinamese (2189) and Dutch (2151)

Total: 562 (9.0%)

Ghanian: 224 (12.0%), African Surinamese: 261 (12.0%), Dutch: 77 (3.6%)

Data from a multi-ethnic HELIUS cohort (The Netherlands)

Age: 18–70 years. Men and women

–

BF%, WHR

WHO criteria (2006): FPG ≥ 7.0 mmol/L, or current use of medication prescribed to treat diabetes, or self-reported diabetes. ADA criteria (2011) are equal to WHO criteria but adds individuals with a HbA1c of 6.5% (48 mmol/mol)

5

Aggarwal, 2022 [15]

White, Asian, Black, Mexican, Other Hispanic American

Total: 19,335

White: 6319

Asian: 258

Black: 4597

Mexican: 2884

Other Hispanic American: 2114

Prevalence, %

White: 9.1 (8.3–10.0)

Asian: 11.9 (10.6–13.1)

Black: 14.3 (13.0–15.7)

Mexican: 12.8 (11.1–14.4)

Hispanic: 10.7 (9.2–12.2)

Data from NHANES, 2011 to 2018 (USA)

Nonpregnant US adults aged 18 to 70 years. Men and women

–

BMI (normal, overweight, obese weight)

UDM: HbA1c level of ≥6.5%

6

Bennet, 2014 [35]

Iraq (Arab), Sweden (White)

Total: 2147

Iraq (Arabic population): 1394; Sweden: 753

Total: 206 (9.6%)

Iraq: 162 (11.6%); Sweden: 44 (5.8%)

Data was collected between 2010-2012 (Sweden)

Men and women born in Iraq or Sweden aged 30–75 years.

Mean age at T2D diagnosis: 47.6 (9.7) for Arab and 53.4 (11.9) for White participants

–

WC, FHD. Adjusted for age, sex, insulin sensitivity index (ISI), corrected insulin response.

FPG level of 7.0 mmol/L and/or by a 2-h plasma glucose level of 11.1 mmol/L. If only one glucose value was pathologic, the OGTT was repeated on another day within 2 weeks

7

Cheong, 2014 [61]

Malay, Chinese, Indian, Other indigenous

Total: 32,703

Malay: 17,959; Chinese: 6636; Indians: 2717; Other indigenous: 3747.

Others: 1644

Total: 3727 (11.4%)

Data from the Third National Health and Morbidity Survey

In 2006 (Malaysia)

18 years and older men and women

18 years and older men and women. Median age was 41 years.

WC (optimal cut-off to predict T2D by gender). Analysis was adjusted for age.

FPG ³6.1 mmol/l or known diabetes

8

Cheong, 2013 [62]

Malay, Chinese, Indians, Other indigenous, Others

Total: 32,703

Malay: 17,959; Chinese: 6636; Indians: 2717; Other indigenous: 3747; Others: 1644

Total: 3727 (11.4%)

Data from the Third National Health and Morbidity Survey

In 2006 (Malaysia)

18 years and older men and women. Median age 41 years. 45,8% men

–

BMI ( < 23 kg/m²; 23.00-24.99 kg/m²; 25.00–27.49 kg/m²; 27.50–29.99 kg/m²; 30.00 kg/m²). Analysis was adjusted for age.

FPG ³6.1 mmol/l

9

Cohen, 2009 [56]

White, African American

Total: 64,435

19,589 African American men, 6202 White men, 27,021

African American women, and 11,623 White women

Total: 13,301 (20.6%)

White man: 1159 (18.7%); African American men: 3302 (16.9%); White women: 2431 (20.9%); African American women: 6409 (23.7%)

Data Southern Community Cohort Study in from 2002 to 2009 (USA)

Aged 40 years and older men and women

–

Weight gain.

Analysis was adjusted to age, BMI at 21years, education, income, smoking, physical activity level, hypertension, marital status.

Self-reported T2D

10

Diaz, 2007 [59]

US white, US black, Mexican American, English white, English black, Indian, Pakistani, Bangladeshi, Chinese

Total: 11,624

US White: 710, US Black: 195, Mexican American: 184, English White: 2116, English Black: 134, Indian: 232, Pakistani: 88, Bangladeshi: 56, Chinese: 121.

Total: 3836 (33.0%)

UDM: US White 2.7%, US Black 5.8%, Mexican American 6.2%, English White 2.3%, English Black 4.3%, Indian 4.1%, Pakistani 6.4%, Bangladeshi 5.9%, Chinese 1.5%

Data from 2003–2004 NHANES and 2003–2004 Health Survey (USA and UK)

20 years or older adults. Men and women.

–

BMI, WC, WHR. Unadjusted

Self-report of doctor diagnosis or HbA1c > 6.1%

11

Gong, 2015 [47]

Uyghur, Han Chinese

Total: 5923

Uyghur: 2863,

Han: 3060

Prevalence of T2D: Uyghurs 10.47%, Han 7.36%

Study was conducted in June-August 2013 (China). Response rate 88.6%

Adults aged 20–80 years. Men and women

–

BMI (adjusted for residency, age, TG, HDL-C, smoking status, drinking status, hypertension)

ADA 2009 criteria: FPG ≥ 7.0 mm/L (126 mg/dL), or/and a previous diagnosis of diabetes

12

Hamoudi, 2019 [40]

UAE, Asian, Arab non-nationals

Total: 3203

Arab non-nationals (640), Asian (1683) and UAE nationals (797)

Total: 614 (19.2%)

Arab non-national: 99 (15.5%).

Asian: 272 (16.2%).

UAE nationals: 243 (30.5%).

Prevalence of newly diagnosed T2D was: UAE men 9.36%, UAE women 11.05%; Asian men 12.04%, Asian women 5.49%; Arab non-nationals men 13.46%, Arab non-nationals women 9.94%.

Data from UAE

National Diabetes and Lifestyle Study (UAEDIAB), UAE

Phase one: all non-UAE national adults aged 18 years and older residing at least 4 years in the UAE.

Phase two: 18 years or older UAE residents. Men and women

–

BMI, WC, FHD.

Adjusted for age, sex, physical activity level, snoring, HDL, TG, high cholesterol, hypertension, SBP, DBP.

FBG ³7.0

mmol/l, ³6.5% HbA1c and participants’

self-report information

13

Huxley, 2008 [63]

Asians and Whites

Total: 263,000

–

Data from Obesity in Asia Collaboration 21 study populations from 11 countries in the Asia-Pacific region (Iran, India, China, Thailand, Singapore, Australia, South Korea, Japan, Taiwan, Philippines)

Men and women

–

BMI, WC, WHR. Analysis adjusted to age.

FPG > 7 mmol/l. Individuals with the history of T2D or on diabetic medication were excluded

14

Jenum, 2005 [34]

Western, South Asians

Total: 2513

Western: 2302, South Asians: 211

Western women: 2.9 (1.9–3.9), Western men 5.9 (4.2–7.5).

South Asian women 27.5 (18.1–36.9), South Asian men 14.3 (8.0–20.7)

Data was collected via collected data using questionnaires, physical examinations and serum analyses (attendance rate 49.3%) (Norway)

30- to 67-year-old men and women in an area of Oslo with low SES

–

BMI, WHR, body height (adjusted for age, physical activity, SE factors (income, years of education))

Known diabetes: self-report. UDM: no previous diabetes and FSG of ³7.0 mmol/l, or HbA1c > 6.4%, or NFSG ³11.1 mmol/l and not attending for fasting venous samples

15

Jenum, 2012 [46]

Norway, Turkey, Vietnam, Sri Lanka, Pakistan

Total: 4110

Norway: 1871, Turkey: 387, Vietnam: 553, Sri Lanka: 879, Pakistan: 420

Total: 406 (9.8%) (Prevalence was higher among Pakistan and Sri Lanka individuals, followed by Turkey, Vietnam and Norway subjects)

Data from the Romsås in Motion Study, Oslo and The Oslo Immigrant Health Study (subjects from Sri Lanka, Pakistan, Vietnam, Turkey and Iran living in Oslo, Norway)

Participants in the Romsås in Motion Study were 30–67 years old and in The Oslo Immigrant Health Study 30–60 years old men and women.

Among known diabetes cases (238) 18 (6.8%) were diagnosed before the age of 25.

–

BMI, WHR x 10, WC, body height, waist-to-stature ratio (WSR) (known as WHTR), parity (0–2, 3, >4).

Adjusted for age (cont.), part/full time work (yes/no), education ( > 9/9 years), heavy PA (yes/no).

Previous T2D: self-reported diabetes.

UDM: FPG or HbA1c or with elevated non-FSG.

16

Li, 2017 [48]

Non-Hispanic white, Non-Hispanic Asian, Others, Hispanic

Total: 1866 (1889)

Non-Hispanic white: 498, Non-Hispanic Asian: 315, Others: 834, Hispanic: 219

The prevalence of diabetes in the Medicaid population was 10.3%, compared with 8.9% in the non-Medicaid population

Data: 2013 through 2015 from the Hawaii Behavioural Risk Factor Surveillance System (USA)

Adults aged 18 years or older. Men and women

–

BMI (adjusted for health insurance status, sex, age, marital status, check-up status, physical activity, immunisation, alcohol consumption)

Self-reported diabetes

17

Lorenzo, 2007 [60]

Mexican American, non-Hispanic white

Total: 7233

SAHS: 2839 (Mexican-Americans and non-Hispanic whites); MCDS: 2233 (white subjects); SIRS: 2161 (Spain)

Among men: Mexico city: 12.8%, San Antonio Mexican Americans 13.7%, San Antonio non-Hispanic whites: 6.5%, Spain: 8.8%.

Among women: Mexico city: 14.2%, San Antonio Mexican Americans: 17.0%, San-Antonio non-Hispanic whites: 5.3%, Spain: 6.7%

Data from 3 population-based studies: San Antonio Heart Study (SAHS) (USA), Mexico City Diabetes

Study (MCDS) (Mexico) and Spanish Insulin Resistance Study (SIRS) (Spain)

SAHS: Mexican American and Non-Hispanic white men and non-pregnant women aged 25–64 years (response rate 65.3%).

MCDS: 35–64 aged men and non-pregnant women (response rate 68.5%).

SIRS: men and non-pregnant women of white ethnicity aged 35–64 years (response rate, 66.9%)

–

BMI, WC, WHR, WHTR

The 2003 ADA FPG

criteria were used to diagnose DM (FPG ³7.0 mM/L, 2-hour glucose 11.1 mM/L) Or (1) treatment not with insulin but with oral anti-diabetic agents; (2) treatment with insulin plus age of diabetes onset

40 years or BMI 30 kg/m2 at enrolment

18

Ntuk, 2017 [5]

Black, South Asian, White

Total: 418,656

Black: 7266

South Asian: 8540

White: 408,530

Total: 18,711 (4.5%).

Black (total, % for men and women): 754, 11.8% and 9.4%.

South Asian (total, % for men and women): 1282, 17.4% and 12.8%.

White (total, % for men and women): 16,675, 5.4% and 3.0%.

UK Biobank (UK)

Men and women aged 40–69 years, who had complete data on diabetes status and hand-grip strength. Ethnicity was based on self-classification into the 19 UK Office of National Statistics groups.

–

Hand grip strength (absolute and relative estimates). Low grip strength was defined as grip strength below the age- and sex-specific overall UK Biobank population median (adjusted for age, education, number of years with diabetes, socio-economic status, percentage body fat, smoking, dietary intake, sleep duration and physical activity)

Self-report of a physician diagnosed T2D

19

Ntuk, 2014 [4]

Black, South Asian, White

Total: 490,288

White: 471,174

South Asian: 9631

Black: 7949

Chinese: 1534

Total: 25,564 (5.2%)

White: 22,880 (4.8%),

South Asian: 1,686 (17.5%), Black: 906 (11.4%)

Chinese: 92 (6.0%)

UK Biobank (UK)

40–69 years men and women

–

BMI, WC, percentage body fat, and WHR (adjusted for age, physical activity, SES, and heart disease)

Self-report of a physician diagnosed T2D

20

Okosun, 1998 [76]

Jamaican, US/African Americans

Total: 3113

Jamaican: 1286

US/African Americans: 1827

-

Data from Ibadan, Nigeria, and local surveys in Spanish Town, Jamaica, and the U.S. NHANES III 1989, 1995 were used in this study. The Nigerian and Jamaican data were part of the International Collaborative Study of Hypert ension in Blacks (ICSHIB) 1994–1996.

25–74 aged men and women

–

WC (first quintile as a reference) (adjusted for age)

ADA criteria: (1) current diagnosis and use of insulin or hypoglycaemic agent or (2) FBG 126 mg/dl or a 2-h postload value of 200 mg/dl in the oral glucose tolerance test

21

Ryckman, 2014 [66]

White, Black, Asian or Pacific Islander, Hispanic, Other/Unknown

Total: 75,993

White: 64,709, Black: 5579, Asian or Pacific Islander: 1840, Hispanic: 2586, Other/Unknown: 1279

Total: 4002 (5.3%)

White: 2720 (4.2%), Black: 778 (14.0%), Asian or Pacific Islander: 141 (7.7%), Hispanic: 252 (9.7%), Other/Unknown: 111 (8.7%)

Data from the Women’s Health Initiative

Observational Study (USA)

Postmenopausal women between the ages of 50 and 79.

–

Self-reported birth weight category (unknown, less than 6 pounds (lbs.), 6–7 lbs. 15 ounces (oz.), 8–9 lbs. 15 oz., and 10 or more lbs) (adjusted for age)

Self-reported physician diagnosed diabetes

22

Strings, 2023 [77]

White, Black, Latin (combining the Mexican American and Other Hispanic groups)

Total: 45,514

–

Data from 10 waves of the continuous National Health and Nutrition Examination Survey from 1999-2000 through 2017–2018 (USA)

Men and women aged 18 years or older

–

BMI (adjusted for age, gender, and year of survey).

Ethnicity was self-reported.

HbA1c

≥ 6.5%

23

Vicks, 2022 [44]

Non-Hispanic White, Chinese, Filipino, South Asian

Total: 373,098

283,110 (non-Hispanic) White, 33,263

Chinese, 38,766 Filipino, and 17,959 South Asian

Total: 52,548 (14%)

Among men.

White: 18,870 (14.3%), Chinese:2,480 (17.5%), Filipino: 5370 (33.7%), South Asian: 2944 (31.7%).

Among women. White: 13,426 (8.9%), Chinese: 1954 (10.2%), Filipino: 5717 (25.1%), South Asians 1787 (20.6%).

Data from integrated healthcare delivery system (EHR) Kaiser Permanente Northern California (KPNC), USA

Men and women aged 45–64 years who were members of a Northern California health plan in 2016

–

BMI (healthy weight, overweight, and obesity categories).

BMI thresholds for White adults (18.5 to<25, 25 to <30, ≥30 kg/m2) and lower BMI thresholds for Asian adults (18.5 to <23, 23 to <27.5, ≥27.5 kg/m2). Underweight range was not included in the analysis (adjusted for age and BMI)

T2D was classified based on laboratory data, clinical diagnoses, or diabetes pharmacotherapy

24

Yoon, 2016 [54]

Korean, White, Black, Hispanic

Total: 23,502

Korean: 18,845

White: 2347

Black: 854

Hispanic: 1456

Data from The 2007 —2010 United States NHANES, USA, and the 2007—2010 Korea National Health and Nutrition Examination Survey (KNHANES), Korea

Adults 20 years or older. Men and women

–

BMI, WC. (adjusted for age, sex, alcohol intake, current smoking status, physical activity, sleep duration, education level, medication of antihypertensive drug, medication for dyslipidaemia, and total daily energy intake, HOMA-IR, HOMA-b)

FPG ≥ 126 mg/dL

25

Zethof, 2021 [39]

African Surinamese, South Asian Surinamese, Turkish, Moroccan, Ghanaian, and Dutch origin. Ethnicity was self-reported.

Total: 21,072

African Surinamese: 3997, South Asian Surinamese: 2956, Turkish:3546, Moroccan: 3850, Ghanaian: 2271, Dutch: 4452.

Total prevalence was 22.1%.

Among men.

Dutch 5.5%, South Asian Surinamese 23.6%, African Surinamese 14%, Ghanian 17.8%, Turkish 12.3%, Moroccan 13.2%.

Among women.

Dutch 14.2%, South Asian Surinamese 20.9%, African Surinamese 14.4%, Ghanian 12.4%, Turkish 10.5%, Moroccan 11.8%.

Participants from HELIUS, the Netherlands

Men and women aged between 18 and 70 years.

Age at T2D diagnosis among men: Dutch 44.26, South Asian Surinamese 43.76, African Surinamese 44.77, Ghanian 45.05, Turkish 41.96, Moroccan 41,87.

Age at T2D diagnosis among women: Dutch 49,39, South Asian Surinamese 43.2, African Surinamese 45.03, Ghanian 44.34, Turkish 42.47, Moroccan 41,17

–

WHR, WC, BMI, body fat % (adjusted for age)

WHO criteria: FPG level ³7.0 mmol/L, had self-reported diabetes, or use of glucose-lowering medication

26

Signorello, 2007 [49]

Whites, African Americans

Total: 43,822

White men: 3165

African Americans men: 14,236

White women: 6326

African American women: 20,095

Total: 9223 (21%)

White men: 20%

African American men: 17%

White women: 21%

African American women: 24%

Data from Southern Community Cohort Study (2002–2006), USA

Men and women 40 and 79 years old (mean age 51.2 years (SD = 8.7))

–

BMI (adjusted for age, educational level, household income, Nam–Powers–Boyd occupational status score, health insurance coverage, body mass index at age 21, hypertension, time per week engaged in moderate sports in 30 s, and time per week engaged in vigorous sports in 30 s)

Self-reported physician diagnosed diabetes

27

Steinbrecher, 2015 [55]

Whites, Native Hawaiians, Japanese Americans

Total: 40,455

White: 16,314 (40.3%), Native Hawaiian: 4970 (12.3%), Japanese American: 19,171 (47.4%)

Total: 4651 (11.5%)

Data from the Multi-ethnic Cohort Study (Hawaii component), USA. Response rates ranged from 28 to 51% in the different ethnic-sex groups

Men and women aged 45–75 years

–

BMI, WC, HC, WHR, WHTR. (adjusted for age, ethnicity, education, physical activity, hypertension, processed red meat intake, dietary fibre intake, smoking and alcohol intake)

Self-reports and by linkages with health insurance plans

28

Nyamdorj, 2010 [45]

Asian Indian, Chinese, Mauritian Indian, European, Japanese

Total: 54,467 (24 515 men and 29 952 women)

Chinese: 4514

Japanese: 3001

Mauritian Indian: 2123

Asian Indian: 5085

European: 9792

Crude prevalence (total) of undiagnosed diabetes ranged from 9.5 to 13.2% among the Asian Indians living in India and Mauritius, from 4.7 to 10.2% in the Japanese and Chinese, and from 4.7 to 6.4% in the Europeans

Data from the population-based DECODA and the DECODE studies (International)

Men and women aged ³30 years

–

BMI, WC (adjusted to age and stratified by gender)

UDM: FPG concentration of ³7.00 mmol l-1 and/or a 2-h post- load plasma glucose concentration of ³11.10 mmol l-1 following a 75-g OGTT.

29

Zhu, 2019 [50]

White, Black, Hispanic, Asian, Hawaiian/Pacific Islander, American Indian/Alaskan Native

Total: 4,906,238

White: 2,454,388; Black:467,994; Hispanic: 1,058,351; Asian: 620,813; Hawaiian/Pacific islander: 67,190; AI/AN: 26,324

Total: 15.9% (age-standardized)

White: 12.2%, Black 21.4%, Hispanic 22.2%, Asian 19.3%, Hawaiian/Pacific Islander: 27.7%, AI/AN: 19.6%

Data from the Patient Outcomes Research To Advance Learning (PORTAL) Network, one of the 13 Clinical Data Research Networks in the National Patient-Centred Clinical Research Network, USA

Men and women aged ≥20 years

–

BMI categories (underweight, normal, overweight, obese class 1, obese class 2, obese class 3, obese class 4) (adjusted for age, sex, neighbourhood poverty, neighbourhood education, and site)

ICD-9 codes or any combination of two other events: fasting plasma glucose $126 mg/dL ($7.0 mmol/L), random plasma glucose $200 mg/dL ($11.1 mmol/L), HbA1c $6.5%, outpatient diagnosis (the same as in- patient codes), or dispensation of an antihyperglycemic medication

30

Abdullah, 2018 [78]

Malay, Chinese, Indian

Total: 4077 (1962 cases and 2115 controls)

Malay: 1323

Chinese: 1344

Indian: 1410

Total: 1962

Malay: 600

Chinese: 654

Indian: 708

Participants from the Malaysian Cohort project, a prospective multi-ethnic, population-based cohort (Malaysia)

35–70 years old adults (men and women).

For all ethnic groups the highest proportion of cases were diagnosed between 50-60 years

–

WC, WHR, FHD.

Adjusted for age, gender, physical activity, sleep duration and location of study.

FPG ≥ 7.5 mmol/L (or 126 mg/dL); a similar number of ancestries matched controls: FPG < 5.5 mmol/L (or 99 mg/dL) without previously diagnosed diabetes

31

Mayer-Davis, 2008 [65]

African American, Hispanic, non-Hispanic white

Total: 247

Cases: 80

Controls: 167 (African American: 28.7%, Hispanic: 18.6%, Non-Hispanic white: 50.9%)

Total: 80

African American: 51.3%,

Hispanic: 20.0%, Non-Hispanic white: 28.8%

Multicentre SEARCH study was conducted in 2001 (Columbia, USA)

Youths aged 10-21 years. Men and women

–

Breast-feeding (yes/no) status and its duration (Reported by biological mother)

Type of diabetes was based on provider diagnosis. Using Health Insurance Portability and Accountability Act– compliant procedures, youth with diabetes identified by the SEARCH recruiting network

32

Marshal, 1993 [79]

Non-Hispanic white, Hispanic

Total: 767 (cases: 279 controls: 488)

Non-Hispanic whites: 391 Hispanics: 376

Total

279

Non-Hispanic Whites: 92

Hispanics: 187

The San Luis Valley Diabetes Study, USA, 1984-1986

20–74 aged men and women. Controls were selected via two-stage sampling and randomly selected to reflect the age structure of cases.

–

BMI (5-unit increase), subscapular skinfold (5-mm increase), triceps skinfold (5-mm increase), subscapular/triceps skinfold ratio (0.2-unit increase), WHR (0.1-unit increase), FHD (adjusted for sex, education, annual income)

Diabetes was defined via health records or self-report

33

Paul, 2017 [43]

White European, African Caribbean, South Asian

Total: 452,915 (90,367/362,548)

White European: 396,350

African-Caribbean: 20,575

South Asian: 36,260

Total: 90 367

White European: 79,270

African-Caribbean: 4115

South Asian: 7252

Data was obtained from the Health Improvement

Network (THIN) database, a large anonymized longitudinal dataset (UK)

18 years or older UK residents. 56% were males, 44% females.

Mean age at diagnosis was 58, 48 and 46 years for whites, African American and South Asians, respectively.

–

BMI at the time of diagnosis of T2D (adjusted for sex, smoking status, deprivation score and history of CVD, cancer and CKD on or prior to the index date)

T2D was diagnosed with the following algorithm: patients with Read Codes related to T2D, and if they received at least 1 prescription of antidiabetic medications or received a lifestyle modification intervention

34

Caleyachetty, 2021 [9]

White, South Asian, Black, Chinese, Arab

Total: 1,472,819.

White: 1333

816 (90,6%), South Asians: 75 956 (5,2%), Black: 49 349 (3,4%), Chinese: 10 934 (0,7%), Arab: 2764 (0,2%)

Total: 97,823 (6.6%).

White 89,287 (6.7%), South Asians 5632 (7.4%), Black

2444 (5.0%), Chinese 317 (2.9%), Arab 143 (5.2%).

Data from EHR CPRD linked to hospital episode statistics, UK

Men and women aged 18 years or older, without past/current diagnosis of T2D and BMI between 15 and 50 kg/m².

The median age

at diagnosis for Whites 67 years (IQR 57–76), South Asians 55 years [45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65], Black 54 years [47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65], Chinese 60 years [52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68], and Arab 56 years [47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64]

Median follow-up 6,5 years (IQR 3,2–11,2)

BMI (adjusted for age and sex)

T2D cases were identified by use of a CALIBRE phenotyping algorithm (a combination of a general practitioner diagnosis of T2D and ICD-10 codes)

35

Dreyfus, 2012 [30]

African American, White

Total: 8491

African American: 2505

White: 5986

Total: 990 (11.6%)

African American: 508 (20.3%)

White: 482 (8.1%)

Participants were selected from the ARIC cohort study (USA)

Women with mean age 54 years.

Excluded: women with missing age at menarche (n = 49), or who reported their age at menarche as 18 years (n = 11), those with diabetes diagnosed before the age of 30 years (n = 30) (potential T1D).

Mean age at diagnosis for African Americans was 49.8 [9], for Whites – 51.3 [9]

9-years of follow-up

Age at menarche (adjusted to age and study centre, BMI)

Self-reported history of physician-diagnosed diabetes, FPG ≥ 7.0 mmol/l (126 mg/dl), non-FPG > 11.1 mmol/l (200 mg/dl) or self-reported use of hypoglycaemic medication in the 2 weeks before the visit for a maximum of 9 years of follow-up

36

Hardy, 2017 [51]

Black Americans, White Americans

Total: 12,121

Black Americans: 2630

White Americans: 9491

Total: 1359 (11.2%)

Black Americans: 427 or 16.2%

(Males 15.39%, Females 16.77%)

White Americans: 932 or 9.8%

(Males 11.73%, Females 8.13%)

ARIC study baseline data was used (USA)

Men and women aged 45–65 years without diabetes at baseline. Mean age was 54 (SD 5.7) years

11 years of follow-up

ABSI, BAI, BMI, WC, WHTR, WHR, WHHR (adjusted for age)

ADA criteria: FPG ≥ 126 mg/dL, non-FBG ≥ 200 mg/dL, self-report of diabetes diagnosis, or self-report of taking diabetes medications

37

MacKay, 2010 [42]

Non-Hispanic White, African American, Hispanic

Total: 1,073

Non-Hispanic white: 430, African American: 282, Hispanic: 361

Total: 146 (13.6%)

The Insulin Resistance Atherosclerosis Study (IRAS), USA

Nondiabetic subjects aged 40–69 years at baseline (1992– 1994). Men and women

5,2 years

WHTR, BMI, WC, WHR, HC

1999 WHO criteria for 2 h OGTT

38

Almahmeed, 2017 [64]

South Asians, Chinese, White

Total: 738,440

Chinese: 34,474; South Asian: 29,474; White: 674,492

DM incidence: Chinese: 1.9%, South Asian: 3.8%, White: 1.9%

Along with primary collected data, Inpatient and outpatient medical records were used (Canada)

Women aged 18–50 years

Follow-up 10 years (from 180 days after index delivery and censored at the first occurrence of the following events: death; loss of insurance coverage or having reached the follow-up)

The index pregnancy (1, 2, 3, 4 and ≥5 deliveries).

Analysis was adjusted to age, income, rural residency, recency of immigration, GDM, pre-existing (chronic) hypertension, gestational hypertension, other comorbidities and Healthcare utilization

The diagnosis of diabetes was made if there was one hospitalization or two outpatient physician service records within 2 years bearing a diagnosis of T2D

39

Chan, 2018 [28]

Malay, Indian

Total: 4101 (Malay 1901 and Indian 2200)

Total: 308 (cum.inc. 12.8%)

Malays: 132 (10.9%)

Indian: 176 (14.7%)

Data from two propective cohort studies: SiMES, 2004–2006, SiME-2, 2011–2013, and the SINDI, 2007–2009, SINDI-2, 2012– 2015 (Singapore)

Mean age of T2D patients was 54.5 years, without diabetes – 55.1 years. Men and women.

Median 6.2 years of follow-up

BMI (underweight/normal, overweight, obese weight). Adjusted for age, gender, ethnicity, family history of diabetes, income, education, current smoking status, systolic blood pressure, HbA1c, total cholesterol, HDL cholesterol and diabetes duration

Random plasma glucose ≥200 mg/dL, HbA1c ≥ 6.5% or self-reported physician diagnosed DM.

40

Chiu, 2011 [29]

White, South Asian, Chinese, Black

Total: 59,824

White: 57,210

South Asian: 1001

Chinese: 866

Black: 747

Total: 4,076 (cum.inc. 6.8%)

Incidence of T2D: White 9.5 (9.1–9.9), South Asian 20.8 (16.1–25.4), Chinese 9.3 (5.8–13.1), Black 16.3 (11.8–21.6)

Participants from Statistics Canada’s 1996 National Population Health Survey (NPHS) and the Canadian Community Health Survey cycles (2001, 2003, 2005), Canada. Survey data was linked to EHRs

Men and women without baseline diabetes aged 30 years or older.

Median age at diagnosis: 49 years among South Asians, 55 years among Chinese, 57 years among Black and 58 years among Whites

12.8 years. Median follow-up 6 years.

Identification of optimal BMI cut-off values

ICD codes from EHRs

41

Kulick, 2016 [80]

Non-Hispanic whites, black non-Hispanics, Hispanics

Total: 2.430

Non-Hispanic whites: 563,

Black non-Hispanic: 576, Hispanic: 1291

Total: 449 (cum.inc. 18.5%)

43 (7.6%) diagnoses of diabetes in non-Hispanic whites, 77 (13.4%) in non-Hispanic blacks, and 329 (25.5%) in Hispanics

Participants in the Northern Manhattan Study without diabetes at baseline was studied from 1993-2014 (USA). Overall enrolment rate was 68%

Individuals who never had stroke and were at least 40 years old. Ethnicity was self-reported. Mean age 69 years. 37% were men

11 years

BMI (sociodemographic, CVD risk factors, CRP)

Self-reported diabetes

42

Luo, 2019 [52]

NHW, American Indian/Alaska Native, Asian, Black or African American, Hispanic/Latina,

Total: 136,112

NHW: 115,412; AI/AN: 524; Asian: 3484; Black or African American: 11,370; Hispanic/Latina: 5322

Total: 18,706

Black women 1.7%, AI/AN 1.5%

Participants were drawn from Women’s Health Initiative prospective cohort study (1993–1998), USA

50–79 years old postmenopausal women.

Race/ethnicity was self-reported.

14.6 years

BMI, WC, WHR, whole-body fat, whole body fat percent, trunk fat, trunk-to-leg fat ratio (adjusted for age at enrolment, education level, FHD, different study cohorts, smoking, alcohol intake, physical activity, HEI-2005 score, high cholesterol level, medicines use)

Self-reported diabetes

43

Lutsey, 2010 [53]

White, Chinese, Black, Hispanic

Total: 546

Analysis was shown for 5603.

Whites: 2360; Chinese: 646; Black: 1442; Hispanic: 1155

Total: 479 (cum.inc. 8.5%) (147 (6.2%) in whites, 150 (10.4%) in blacks, 48 (7.4%) in Chinese, and 134 (11.6%) in Hispanics)

Data from the MESA initiated in 2000, USA

45-84 years US men and women

6.6 years (median 4.7)

BMI, WC (adjusted for age, sex, race/ethnicity, education, and income)

Incident diabetes: Participants taking diabetes medications or whose glucose, after a minimum 8-hour fast, was ³126 mg/dL at any of the follow-up examinations

44

Ma, 2012 [23]

White, Black, Hispanic, Asian

Total: 158,833

White (NHW): 133,541

Black (NHB): 14,618

Hispanic: 6484.

Asian: 4190

Total 14,604 (cum.inc.9.2%)

White: 11,127 (8.63%),

Hispanic: 879 (14.63%)

Black: 2181 (17.01%)

Asian: 417 (10.58%)

Participants from the Women’s Health Initiative Study (USA)

50–79 years old postmenopausal women. The average age was 63 at baseline

Average 10.4 years

BMI ( < 25 kg/m2 vs. ³25 kg/m2)

Self-reported diabetes

45

Maskarinec, 2009 [67]

White, Japanese American, Native American, Hawaiian, Others

Total: 103, 898

White: 35,042

Japanese American: 44,513

Native Hawaiian: 14,346

Other: 9997

Total: 11,838 (cum.inc.11.4%)

White: 2386 (5.8 [5.0–6.6]),

Japanese American: 5957 (12.5 [11.4–13.5]),

Native Hawaiian: 2182 (15.5 [13.3–17.6]), Other: 1313 (12.2 [9.9-14.4])

Participants from Hawaii component of the Multi-ethnic Cohort, (1993-1996 followed until 2007), USA

47% men and 53% women

Mean follow-up 11.9 ± 3.4

BMI (adjusted for age, sex, and education)

Self-report and the information obtained through the health plan linkages

46

Morimoto, 2011 [57]

Native Hawaiians, Whites, Japanese Americans

Total: 78,006

Native Hawaiians: 10,877; Whites: 30,715; Japanese Americans: 36,414

Total: 8892 (11.4%)

Native Hawaiians: 1,792 (16.5%)

Whites: 1870 (6.1%)

Japanese Americans: 5230 (14.4%)

By gender (men/women, in %): White 7.2/5.0, Japanese American 16.1/12.8, Native Hawaiian 17.2/15.9.

The Multi-ethnic Cohort Study, 1993-1996 (with 5.5 years of follow-up), Hawaii (USA)

45–75 years individuals. Men and women

5.5 years ( ± 0.8)

Self-reported weight gain (at baseline of the study, at age 21 and after 5.5 years) (adjusted for gender, age, education, physical activity and BMI at age 21)

Diabetes was diagnosed through self-report and a linkage to medical databases

47

Narayan, 2021 [81]

South Asian, White, Black

Total: 16,119

South Asian: 3.136

White: 9924

Black: 3.059

Total: 2,013

South Asians (total, age-adjustedd incidence for men/women): 389 (26 [22.2–29.8] and 31.9 [27.5–36.2])

White (total, age-adjusted incidence for men/women): 1036 (16.1 [14.8–17.4] and 11.3 [10.2–12.3])

Black (total, age-adjusted incidence for men/women): 588 (26.2 [22.7–29.7] and 28.6 [25.7–31.6])

Prospective Centre for Cardiometabolic Risk Reduction in South Asia Study (CARRS) and the ARIC Study (India, Pakistan and US)

Men and women free of diabetes at baseline and aged 45 years

4.8 (3.8–5.1) years in CARRS and median follow-up time: 8.8 years, IQR 5.6–9.0 years in ARIC study

BMI, FHD (adjusted for age, sex, log-HOMA-IR, log-HOMA-B)

In the CARRS and ARIC cohorts, incident diabetes was defined as FPG ≥ 7.00 mmol/L (126 mg/dL), HbA1c ≥ 6.5% (48 mmol/mol) or self-reported diabetes or on medication during follow-up

48

Resnick, 1998 [33]

Black, White

Total: 11,383

1531 black and 9852 white subjects

Total: 1139 (10%)

Black: 260 (17%),

White: 879 (9%)

National Health and Nutrition Examination Survey, Epidemiologic Follow-up Study (1971–1992), USA

Men and women who were ages 25–74 years during the NHANES I and who completed the baseline medical examination

20 years of follow-up

BMI and subscapular-to-triceps skinfold ratio (STR) (adjusted for age)

Self-report, health record data or death certificates

49

Rodriguez, 2021 [82]

White, African American, Hispanic, Chinese Americans

Total: 5659

White: 2383

African American: 1462

Hispanic: 1161

Chinese Americans: 653

Total: 696 (12.3%)

MESA cohort (2000–2001), USA

45–84 years men and women. Mean age was 62 years

42 686 person-years/11 years of follow-up

BMI.

Ethnicity was self-reported.

FPG ≥ 7.0 mmol/l, or use of any diabetes medications

50

Shaten, 1993 [83]

Blacks, non-Blacks

Total: 6000

White: 5420; Black: 428

Asian: 56

Hispanic: 70

Other: 26

Total: 4.1% or 247 cases

Blacks: 28 or 6.5%. Non-Blacks (all other ethnicities combined): 219 or 3.9%

Data/participants from the Usual Care group of the Multiple Risk Intervention Trial (USA)

Men only. Average age was 46 years, BMI 27.6 kg/m²

5 years

Self-reported parental history of diabetes

T2D was defined as use of insulin/hypoglycemic agents, FPG ³140 mg/dl on two consecutive annual visits, or FPG ³140 mg/dl followed the next year by insulin or hypoglycaemic use

51

Stevens, 2008 [38]

Chinese Asians, American Whites, American Blacks

Total: 20,338

Chinese Asians: 5980, American Whites: 10,776, American Blacks: 3582

Cumulative incidence: Chinese Asians 5.8 (4.5–7.1), American Whites 4.3 (3.7–5.0), American Blacks 8.7 (7.0–10.3)

People’s Republic of China Study (1983–1994), China, and the Atherosclerosis Risk in Communities Study (1987–1998), USA

Men and women aged 45–64 years at baseline

Average 8 years of follow-up

BMI (adjusted for gender, baseline age, education, smoking status, alcohol consumption, field centre)

FPG ³126 mg/dl, reported taking diabetes medication, or self-reported physician diagnosed diabetes

52

Tillin, 2014 [41]

Europeans, South Asians, African-Caribbeans

Total: 2533 (1356 Europeans, 842 South Asians, 335

African-Caribbeans)

Diabetes incidence rates (per 1000 person years) were 20.8 (95% CI: 18.4, 23.6) and 12.0 (8.3, 17.2) in South Asian men and women, 16.5 (12.7, 21.4) and 17.5 (13.0, 23.7) in African-Caribbean men and women, and 7.4 (6.3, 8.7), and 7.2 (5.3, 9.8) in European men and women

Southall and Brent Revisited (SABRE) is a population-based cohort of Europeans, South Asians and African- Caribbeans from North and West London (UK)

Men and women aged 40-69 years at baseline (1988– 1991)

All South Asians and African-Caribbeans were first-generation migrants. Ethnicity was confirmed based on parental origins

19 years of follow-up

BMI categories (using suggested WHO cut-points of <23, 25, 27.5 and 30 kg/m2) and by baseline WC in 10 cm categories (adjusted for sex and age)

Primary care records, participant recall and/or follow-up biochemistry

53

Wei, 2015 [58]

Black, White

Total: 17,404

Black: 3655; White: 13,749

Diabetes incidence per 1000 PY in the younger and middle-aged groups was 7.2 (95% CI 5.7, 8.7) and 24.4 (22.0, 26.8) in blacks, respectively, and 3.4 (2.8,4.0) and 10.5 (9.9, 11.2) in whites, respectively

Participants from ARIC, CARDIA, and the Framingham Heart Study (USA)

56% women, 44% men

The age ranges in ARIC, CARDIA, and the

Framingham Heart Study were 44-59, 30-46, and 30-59 years, respectively

Median follow-up 9 years

Duration and degree of weight gain. Models were adjusted for sex, baseline HDL-C, log(triglycerides), fasting Ng glucose, prehypertension, hypertension, log (BMI-years below baseline BMI), as well as for interaction terms

FBG ³126 mg/dL, casual blood glucose

³200 mg/dL, or using insulin or oral hypoglycaemic medication

54

Zamora-Kapoor, 2018 [84]

Non-Hispanic Whites, non-Hispanic blacks, AI/AN

Total: 8337

Non-Hispanic Whites: 5131

Non-Hispanic Blacks: 1651

Hispanics: 1223

American Indians/Alaska Natives: 332

Total: 484

Diabetes was more prevalent in non-Hispanic Blacks (12%) than in American Indians/Alaska Natives (11%), Hispanics (6%), and non-Hispanic Whites (3%)

the Add Health Study (1994–2008), USA

Males and females were 11–20 years old (mean age: 16 years) at baseline in 1994 and were followed for additional waves of data collection in 1996, 2002, and 2008. Retention rates in all waves was between 72% and 79%. 53% were females

Mean follow-up time was 14 years

BMI, FHD.

Age, gender, physical activity level, parental education and financial instability. Both parents and adolescents completed questionnaires

HbA1C

≥ 6.5%, glucose > 125 mg/dl, self-reported diabetes, or self-reported diabetes medication use