Global burden of Diabetes:Prevalence and projections

Belllagio, March 16th 2004

Peter H. Bennett, M.B., F.R.C.P.National Institute of Diabetes and Digestive and

Kidney Diseases,Phoenix, Arizona, U.S.A.

Outline

• Prevalence of Diabetes

• Estimates of future prevalence (projections)

• Mortality attributable to diabetes

• Effect of the epidemic on rates of complications

• Projections for ESRD

Newsweek, September 4,Newsweek, September 4, 20002000

Newsweek, September 4,Newsweek, September 4, 20002000 Time, September 4, 2000Time, September 4, 2000Time, September 4, 2000Time, September 4, 2000

Diabetes in 2000 & 2025in USA and the World

King,H, Aubert,RE, Herman,WH: Global burden of diabetes, 1995-2025: Diabetes Care 21:1414 - 1431, 1998

151million300 million

15 22USA

Diabetes in 2000 & 2030in USA and the World

Wild, S et al.: Global prevalence of diabetes: Estimates for 2000 and projections for 2030. Diabetes Care 2004 In press

171million366 million

17.7 30.3USA

Global Projections for the Diabetes Epidemic: Global Projections for the Diabetes Epidemic: 2000-2030 (in millions)2000-2030 (in millions)

NA19.733.972%

LAC13.333.0

248%

EU17.825.141%

A+NZ1.22.065%

SSA 7.118.6261%

World2000 = 171 million2030 = 366 million

Increase 213%

China20.842.3204%

Wild, S et al.: Global prevalence of diabetes:Estimates for 2000 and projections for 2030 Diabetes Care 2004 In press

India31.779.4251%

MEC20.152.8

263%

Estimated Number of People with Diabetes in 2000 and 2030 (and % change)

Wild, S et al.: Global prevalence of diabetes: Estimates for 2000 and projections for 2030 Diabetes Care 2004. In press

+176%

+26%

-13%

Estimated Number of People with Diabetes in 2000 and 2030 (and % change)

Wild, S et al.: Global prevalence of diabetes: Estimates for 2000 and projections for 2030 Diabetes Care 2004 In press

+308%

+247%

+189%

Estimated Number of People with Diabetes in 2000 and 2030

Wild, S et al.: Global prevalence of diabetes: Estimates for 2000 and projections for 2030 Diabetes Care 2004 In press

+242%

+212%

+75%

Are these projections realistic?

Based on:1990s estimates of diabetes prevalenceDemographic projectionsAssume constant (current) age-sex specific

prevalence of diabetes

Changing Prevalence of Type 2 Diabetes

No of persons with Physician-diagnosed Diabetes in USA by year

Data from the US National Health Interview Survey: http://www.cdc.gov/diabetes/statistics/prev/national/fig1.htm

Diabetes in the United States1958-1993

Prevalence (%)

> 65 years

55-65 years

45-54 years

< 45 years

Data from the US National Health Interview Survey

Diabetes in the United States1980-2000

Prevalence (%)

< 45 years

65-74years

45-64years

75+years

Data from the US National Health Interview Survey:http://www.cdc.gov/diabetes/statistics/prev/national/fig3.htm

Mokdad A. H et al. Diabetes Care 23: 1278-1283Mokdad A. H et al. Diabetes Care 24: 412

1991 1999%

Increase

Men 4.1% 6.0% 46%

Women 5.6% 7.6% 36%

Diabetes Epidemic in the United States, 1991-1999

Percent with Diagnosis of Diabetes(Aged 18 years and over)

increase = 5%/ year

1991 1998%

Increase

Men 11.7% 17.7% 51.5%

Women 12.2% 18.1% 47.4%

Obesity Epidemic in the United States, 1991-1998

Percent with BMI > 30 kg/m2

Mokdad A.H. et al. JAMA 1999; 282:1519 - 1522

Why were former projections inaccurate?

• They were based on demographic changes (which are very predictable)

• The epidemic of diabetes is driven by other factors (some or perhaps most of which may be reflected in occurrence of IGT and IFG)

Importance of IGT and IFG

IFG

IGT

'Impaired Glucose Tolerance’ (IGT) 2h post-load Plasma Glucose of 140-199mg/dl [7.8-11.0mmol/l] and FPG <126mg/dl [<7.0mmol/l]

Impaired Glucose Homeostasis

'Impaired Fasting Glucose' (IFG) FPG of 100-125mg/dl [5.6 -<7.0mmol/l]

Incidence of Diabetes in people with Impaired Glucose Homeostasis

Prevalence and Incidence of Diabetes (%) in Impaired Glucose Homeostasis

Prevalence of Impaired Glucose Homeostasis

5-year Cumulative

Incidence of DM

Hoorn 50-75y

19.4 29.7

Mauritius 25-74y

19.3 24.5

Pima Indians 15+y

15.1 24.8

Nhanes III 40-74y

19.3 ? 25% ?

Projections of Numbers with Diabetes* among persons aged 40-74years in USA (Millions)

14.518

21.525

28.532

35.5 39

0

10

20

30

40

1995 2000 2005 2010 2015 2020 2025 2030

YEAR

No.

with

Dia

bete

s (m

illion

s)

*Based on diabetes incidence (5% / year) in the 20% of persons with impaired glucose homeostasis; 300,000 diabetes deaths / year; Net increase = c.700,000 cases of diabetes / year

Proportion of new cases of Diabetes (%) in persons with NGT and Impaired Glucose Homeostasis

Proportion from persons with NGT

Proportion from those with IGT or IFG

Hoorn 50-75y

38% 62%

Mauritius 25-74y

40% 60%

Pima Indians 15+y

44% 56%

Nhanes III 40-74y

? 40% ? ? 60% ?

Projections of Numbers with Diabetes* among persons aged 40-74years in USA (Millions)

19.424.3

29.234.1

3943.3

48.2

14.518

21.525

28.532

35.539

0

10

20

30

40

50

1995 2000 2005 2010 2015 2020 2025 2030

YEAR

No.

with

Dia

bete

s (m

illio

ns)

*Based on diabetes incidence (5% / year) in the 20% of persons with impaired glucose homeostasis; 40% of new cases from persons with NGT; 450,000 diabetes deaths / year Net increase = c.830,000 cases of diabetes / year

Diabetes in 2000 & 2030

171million 366 million530 million?

17 19.4 30.3 48.9USA

Mortality attributable to diabetes

Number of Deaths with Diabetes as Underlying Cause of Death,United States, 1980-1996.

CDC, Diabetes surveillance, 1999

Excess Deaths attributable to Diabetes

• Excess mortality =No of deaths in DMs – Expected no. if not DM

• No of DM deaths = (RR of death in DM x No. with DM)

• Expected No. = Mortality rate in non DMs*No. with DM

• Mortality rate; RR of death in DM; No. with diabetes

DECODE study group, Lancet 1999; 354, 617-621

1

1.49

1.99

1

1.54

2.6

NGT IGT DM0

0.5

1

1.5

2

2.5

3

Rel

ativ

e R

isk

Men

Women

Hazard Ratios for death in Normal (NGT), Impaired glucose tolerance (IGT) and diabetes

(DECODE Study, 25364 subjects aged 25+, mean follow-up 7.3 years)

Age-standardized Mortality (22 year follow-up)in Diabetic and Non-diabetic adults

(NHANES I, aged 25 or older)

DiabeticMen

Non-diabeticmen

DiabeticWomen

Non-diabetic women

0

10

20

30

40

50

Mor

tali t

y /1

000

p er s

o n-y

ears

All causes

Gu,K et al. Diabetes Care 21, 1138-1145, 1998

2.03 x

2.22 x

Global Projections of Excess Deaths attributable to Diabetes (in 000’s)

and percent of all deaths in year 2000

AMRA251.19.75%

AMRD32.26.1%

EUR609.06.4%

WPR469.34.1%AFR

319.22.6%

WorldIn 2000 = 3.164 million

(5.4% of all deaths)

SEAR1154.16.9%

Roglic et al.: Burden of mortality attributable to diabetes:Estimates for the year 2000. In preparation

EMR125.37.2%

AMRB194.07.6%

Consequences of the Epidemic

Consequences of Epidemic

• Disproportionate increase in duration-related complications

• Increase in number with diabetes

Effect of Epidemic of Diabetes on Duration-related complications

16 new cases/yr. Death occurs after 30y DM; Complication incidence 50% after 15y DMAfter 30 years No. of new cases equals no. of deaths.

0 5 10 15 20 25 30 35 40 45 50

Time (years)

0

150

300

450

No.

of

Cas

es

0

10

20

30

40

50

Percent w

ithcom

plicationsCumulative No. of DM cases

% with DM>15y duration

Prevalence of complications (%) among those with DM

Incidence of Type 2 Diabetes in Pima Indians in two time periods

1965-75

1975-85

Time Period

0 10 20 30 40 50

Incidence per 1000 person-years

Age-sex adjusted rates

60% increase

Age-standardized mortality from Ischemic Heart Disease in diabetic and non-diabetic

Pima Indians aged 35+ years, (30 year follow-up)

1965-74 1975-84 Non-diabetic

1985-94 1965-74 1975-84 Diabetic

1985-940

1

2

3

4

5

6

Mo

rtal

ity

/100

0 p

erso

n-y

ears

Renal disease

1965 1970 1975 1980 1985 1990 1994

Year

0

5

10

15

20

25C

ases

Dialysis

Deaths

Frequency of Renal Failure among Pima Indians

1965-74 1975-84 1985-94

Time Period

0

4

8

12

Ca

ses

pe

r 1

00

0/y

ea

rIncidence of Renal Failure

Number of persons beginning treatment for

ESRD attributable to diabetes in USA by year

http://www.cdc.gov/diabetes/statistics/esrd/Fig1Detl.htm

DIABETES IN END-STAGE RENAL FAILURE: AUSTRALIA 1980 - 2000

Year of Entry

Number of Diabetics Number of New Patients

0

100

200

300

400

500

80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00

0

300

600

900

1200

1500

1800

Type 2 (Ins Requiring)

Type 2 (Non Insulin)

Type 1

Total New Patients

Crude and Age-adjusted incidence of ESRD related to diabetes in the United States

1984-2001Incidence/100,000 Diabetic persons

Age-adjusted rate

Data from the US Renal Data System:http://www.cdc.gov/diabetes/statistics/esrd/fig7.htm

Crude rate

Projections for number of patients with diabetes initiating ESRD treatment in USA*

2000 2030

(using WHO estimate)

2030

Revised projections

Number with Diabetes

18 million 31 million 39-48 million

No with new ESDR

40,000 68,000 86-105,000

* Assuming current incidence rates for initiating ESRD treatment remain constant

Summary

• Based on demographic changes alone:The numbers of persons with diabetes in the

world will more than double in the next 30 years• In developed countries they will increase by

30-70% (mostly in older persons)• In developing countries they will increase by c.

250% (mostly in 45-64y age group)• These projections do not take into account any

increase that is attributable to future increases in obesity

Summary

• c.3.2 million (excess) deaths were attributable to diabetes in year 2000.

• • In the USA this is 9% of all deaths

– e.g. In USA c.200,000 excess deaths vs. 14,500 for AIDs

• The numbers of deaths attributable to diabetes in future years will increase especially in developing countries

Summary

• Because of the current epidemic of diabetes, reflected in increasing age specific prevalence, the proportion of the diabetic population with complications will increase.

• This will result in a greater relative increase in complications than in diabetes prevalence.

• Because serious complications e.g. ESRD, typically develop after 15-20 years duration, the incidence of ESRD due to diabetes will continue to increase for at least the next 20 years

Conclusions

Increase in Type 2 diabetes (and obesity) represents the major public health challenge for the 21st century

The estimates of future burden currently used seriously underestimate what is going to happen!

Thank you

Age-adjusted incidence of ESRD related to diabetes in the United States

1984-2001Incidence/100,000 Diabetic persons

White female

Black femaleHispanic male

Black male

Data from the US Renal Data System:http://www.cdc.gov/diabetes/statistics/esrd/fig5.htm

White maleHispanic female

Amer. Indian maleAmer. Indian female

Are there better ways to predict future trends?

• Incidence = No. of new cases/ period of time• Mortality = No. of deaths/ period of time• Prevalence=Cumul.incidence – Cumul. Mortality• = Number of cases at a point in time• Future no. of cases = No. of prevalent cases + no.

of new cases- No. of deaths(among all cases)