Effectiveness of diabetes and hypertension management by rural primary health-care workers (Behvarz workers) in Iran: a nationally representative observational study

Farshad Farzadfar, MD, MPH, D.Sc

Non Communicable Diseases Research CenterEndocrinology and Metabolism Research Institute Tehran University of Medical Sciences

July 13, 2012

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SAPHIR Monthly Webinar

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Outline of the presentation

• Epidemiology of metabolic risk factors at global, regional, and country levels

• Objectives of the study

• Methodology and results of phase one of the study

• Methodology and results of phase two of the study

• Conclusion and take home messages

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Global epidemiologic transition

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Lopez et al. Lancet 2006

Age-standardized cardiovascular mortality trends in selected high-income countries

Vital registration data from WHO

0

4

8

12

16

20

1950 1960 1970 1980 1990 2000 2010

Year

Dea

th R

ate

(per

1,0

00)

USA

Denmark

Finland

Sweden

UK

Australia

Female - CVD

0

4

8

12

16

20

1950 1960 1970 1980 1990 2000 2010

Year

Dea

th R

ate

(per

1,0

00)

Male - CVD

Male Female

Regional FPG trends

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North America

North America

Mal

eF

emal

e

North Africa and Middle East

Danaei et al. Lancet 2011

North Africa and Middle East

Ma

le F

em

ale

FPG, BMI and SBP trends in Iran between 1980 and 2008

FPG BMI SBP

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Farzadfar et al. Lancet 2011, Finucane et al. Lancet 2011, Danaei et al. Lancet 2011

4.0

4.4

4.8

5.2

5.6

6.0

1980 1990 2000 2010

mm

ol/L

20

22

24

26

28

30

1980 1990 2000 2010

kg/m

^2

20

22

24

26

28

30

1980 1990 2000 2010kg

/m^2

115

120

125

130

135

140

1980 1990 2000 2010

mm

Hg

4.0

4.4

4.8

5.2

5.6

6.0

1980 1990 2000 2010

mm

ol/L

115

120

125

130

135

140

1980 1990 2000 2010

mm

Hg

The effects of risk factors on life expectancy in 2005, by region

Fe

ma

leL

ife

ex

pe

cta

nc

y

Southeast North-Northeast West Central National

Ma

leL

ife

ex

pe

cta

nc

y

Southeast North-Northeast West Central National

8Farzadfar, et al, population Health metrics, 2011

Iran’s health system

Inputs Rural areas Urban areas

Population 32% 68%

Primary healthcare system Well-established

High coverage rates

Inefficient

Low coverage rates

Insurance coverage 63% before 2005 and 94% in 2008

77%

General practitioners 6,250 52,700

Specialists 135 14,300

Nurses/midwives 4,470 62,600

Behvarz 32,000 0

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Annual report of MoH . 2005 , Utilization study. 2005

The objectives of the study

• Phase one: Estimating prevalence, diagnosis and coverage of treatment for diabetes and hypertension by

residency area

Estimating the treatment effects of diabetes and hypertension by residency area

• Phase two:

Estimating the association of Behvarz density with levels of FPG (which has an integrated and well defined program in PHC) and SBP

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Data source and definitions

• Data source: Non-Communicable diseases surveillance survey (2005)

• Diabetic definition: Fasting plasma glucose (FPG) ≥ 126 mg/dl or on medication to control blood sugar (either oral anti-hyperglycemic agents or insulin)

• Hypertensive definition: Blood pressure (SBP/DBP) ≥ 140/90 mmHg or on medication to control blood pressure

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Estimation of treatment effects

• Matching:

– All treated individuals were matched to controls based on propensity score of their age, sex, BMI, education and wealth index

• Random intercept regression analysis with an instrumental variable:

– A proxy for potentially unobserved confounders that could affect the use of treatment but not the distribution of risk factors

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Age standardized prevalence of diabetes and hypertension by sex and urban and rural residence

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Hyp

erte

nsi

on

Ag

e s

tan

da

rdiz

ed

pre

va

len

ce

RuralUrban Country

Dia

bet

esA

ge

sta

nd

ard

ize

d p

rev

ale

nc

e

RuralUrban Country

Diabetes and hypertension diagnosis in Iran

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Coverage of treatments for diabetes and hypertension in Iran by sex and urban and rural residence

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Dia

bet

esC

rud

e c

ov

era

ge

of

tre

atm

en

t (

pe

rce

nt)

RuralUrban Country

Hyp

erte

nsi

on

Cru

de

co

ve

rag

e o

f tr

ea

tme

nt

(p

erc

en

t)

RuralUrban Country

Treatment coverage of diabetes and hypertension by wealth quintile

Pro

ba

bil

ity

of

rec

eiv

ing

tre

atm

en

t

16Wealth quintile

Coefficients of regression to estimate the effect of diabetes and hypertension treatment on fasting plasma glucose and systolic blood pressure of treated

individuals

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The average effect of treatment by area of residency

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Tre

atm

en

t e

ffe

cts

fo

r h

yp

ert

en

siv

ein

div

idu

als

(m

mH

g)

RuralUrban

Tre

atm

en

t e

ffe

cts

fo

r d

iab

eti

cs

(m

mo

l/L

)

RuralUrban

What could be the reason for the diabetes treatment effect differences between rural and urban areas?

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Behvarz

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Data sources

• Risk factor exposure:

Non-communicable diseases surveillance survey (2005)

• Behvarz :Census data (2006)

• Physician: Outpatient care center mapping (2005)

• ICU bed Ministry of health database (2005)

• Other socioeconomic indicators Census data (2006)

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Methods

• Propensity score matching:

– Individuals living in districts falling in different Behvarz density quintiles were matched based on age, sex, body mass index (BMI), education, marital status, wealth index, physician density, ICU bed density and employment rate

• District level random intercept regression:

– Adjust for age, sex, BMI, education, marital status, wealth index, physician density, ICU bed density and employment rate

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The association between Behvarz and physician densities and district average wealth index

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Coefficients of regression to estimate the effect of Behvarz-worker density on fasting plasma glucose and systolic blood pressure in Iran

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Average effect of Behvarz-worker density on fasting plasma glucose (A) and systolic blood pressure (B)

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Take home messages

• Risk factors with large burden but no current program to control

• Sub-national level policy making

• Primary healthcare as an effective management of chronic conditions such as diabetes

• Cost considerations

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Acknowledgements

Co-authors and colleagues

• Majid Ezzati• Thomas Bossert• Hengameh Namdari• Siamak Alikhani• Hamidreza Jamshidi

Co-authors and colleagues

• Christopher Murray• Emmanuela Gakidou• Ghobad Moradi• Alireza Delavari

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Thank you

comments/questions?