THE NEED OF PREVENTION PROGRAMMES

IN AFRICA

SARALA NAICKERDivision of Nephrology

University of Witwatersrand

Johannesburg, South Africa

MAJOR PROBLEMS IN AFRICA

Poverty Rapid urbanization Overcrowding Lack of clean water Inadequate sanitation Wars, crime, violence

HEALTH PROBLEMS IN AFRICA

•Infectious diseases

43% in Africa

1.2% in developed world• tuberculosis

• malaria

• acute respiratory infections

• diarrhoeal diseases

• HIV/AIDS

•Trauma/ violence•Increase in non-communicable/ chronic disease

Major causes of death

23.1

WHO,1997

7.77. Other/unknown

01.56. Maternal causes

19.15. Perinatal & Neonatal causes

8.14.84. Respiratory diseases

219.53. Cancers

45.624.52. Disease of the circulatory system

1.2431. Infections & parasitic diseases

Developed world (%)Developing World (%)Causes of death

World

19902020

10.6 m20.2 m

4.1 m5.6 m

Developed Developing

6.5 m14.5 m

4.1

5.7

1.40.6

1.30.6

3.6

1.6

3.9

2.0

0.82.0

1990

2020

* In million subjects

37%

144%

130%

119%

96%

139%

THE GLOBAL BURDEN OF CARDIOVASCULAR DISEASE MORTALITY (1990-2020)

2.10.8

157%

CHRONIC RENAL FAILURE

High incidence in Afro-Americans (Easterling 1977; Mausner et al, 1978; Rostand et al, 1982)

Impression : 3 - 4 x more prevalent in Africa (Barsoum et al, 1974; Abdulla, 1979; Abdullah 1981).

Birth weight and Renal disease• 2000 Lackland et al. USA:

– Black 30% of population but 69% of ESRD population

– 70% of ESRD attributed to HT– Low birth weight associated with ESRD of

all causes

• 1998 Hoy et al. Australia: Aborigines– 21 x renal disease– High rate of low BW, HT, T2 DM, CVD,

obesity

People of African Origin• 1996 Forrester et al. Jamaica: 1610 kids

6-16y– SBP inversely related to BW

– ↑ HbA1c in children shorter at birth

• 1999 Levitt et al. Soweto: 849 5y olds– SBP ↓ by 3.4 mmHg for every 1Kg ↑ BW

• 1999 Longo-Mbenza et al. DRC: 2648 school children– Odds ratio of 2 for ↑ BP with low birth weight

People of African Origin

• 1998 Woelk et al. Zimbabwe: 756 6-7y.o.– SBP ↑ by 1.73 mmHg for every 1Kg ↓ BW

• 2000 Olatunbosun et al. Nigeria: 988 adults– Negative correlation with height and IGT but not BP

• 2000 Steyn et al. Soweto (BTT): 964 5y.o.– SBP and DBP significantly higher in black children

LOW BIRTH WEIGHT AND IMPAIRED RENAL DEVELOPMENT

REDUCED FILTRATION

SURFACE AREA

POVERTY, MATERNAL MALNUTRITION, MATERNAL HT

GLOMERULAR/SYSTEMIC

HYPERTENSION

ACQUIRED GLOMERULOSCLEROSIS

OTHER “HITS”

DM, HT, Pyelonephritis, obesity, environmental factors, diet, stress

GN IN CHILDREN

• 20 year review- 636 children with NS Indian: Total 286 minimal change 46.8%

FSGS 20.6% (prev. 1.8%) Black: Total 306 minimal change 14.4% FSGS 28.4% (prev. 5%)

Bhimma et al, Ped Nephrol,1997

CRF IN NIGERIA

10 year study

368 patients / 10% of medical admissions

Aetiology : Undetermined 62%

Rest- Hypertension 61%

DM 11%

Chronic GN 5.9%

(Mabayoje et al,1992)

CRF IN TROPICAL AND EAST AFRICA

Aetiology Chronic GN Hypertension

(Nseka and Tshiani, 1989

McLigeyo and Kaying,1993)

PRIMARY RENAL DISEASE CAUSING ESRD IN S AFRICA

Number of PatientsSADTR 1994

0 500 1000 1500 2000

GN

HPT

Unknown

Multisystem

CIN

Drugs

Cystic disease

Other

Hereditary

SADTR DATA

• Causes of ESRD in 8576 patients– GN 23%– Hypertension 21%

• 25% of adult population• Malignant hypertension: 16% of hospital

admissions

SADTR, 2000

40 % of diabetics are at risk of overt nephropathy

Diabetic patients with renal disease have a 5-6 fold increased mortality rate as compared to diabetic patients with no signs of renal disease or healthy subjects

THE FACTS

World

20002025

154 m300 m

55 m72 m

Developed Developing

99 m228 m

16.724.5

39.3

18.2

38.430.7

21.8

9.1

57.2

22.8

37.5

18.6

0.4 0.7

2000

2025

* In million subjects

47%

116%

25%

140%

150%

102%

64%

THE GLOBAL BURDEN OF DIABETES (2000-2025)

DIABETIC NEPHROPATHY

• South Africa 14-16%

• Zambia 23.8%

• Egypt 12.4%

• Sudan 9%

• Ethiopia 6.1%

Amos et al (1997). Diabetic Medicine

Type 2 Diabetes Mellitus

Type 2 DM prevalence: 13.7% I 6.7% B

Amod, SEMDSA abstracts 1996

0.00%

10.00%

20.00%

30.00%

40.00%

50.00%

60.00%

70.00%

80.00%

90.00%

Retinal Prot.-uria HPT GFR Creat.

Blacks

Indians

Total (n=172)

MICROVASCULAR COMPLICATIONS of DIABETES MELLITUS

Type 1 DM

0%

10%

20%

30%

40%

50%

60%

Retinal Prot.-uria HPT GFR Creat.

Blacks

Total (n=47)

Indians

NEPHROTIC SYNDROME

greater frequency, compared to temperate regions

hospital admissions Zimbabwe 0.5% Kwazulu Natal , S Africa 0.2%

Uganda 2% Nigeria 2.4%

Seedat,1996

RENAL DISEASE IN EAST AFRICA

2-3% of medical admissions poor response to treatment progression to renal failure

Presentation: commonly – nephrotic syndrome; age of onset 5-8 years

Infectious aetiology : p malariae, schistosomiosis, HBV, streptococcal infections, syphilis, leprosy, filariasis, hydatid disease

Mc Ligeyo, 1990

GN

• Sudan 36.6%

• Cote d’Ivoire 49.1%

• Egypt 11%

• Saudi Arabia 28%

Barsoum, 2002

RENAL DISEASE IN NORTH AFRICA

• GN 18-24%

• Interstitial nephritis 14-32%

• Diabetic nephropathy 5-20%

• Nephrosclerosis 5-18%

Barsoum, 1998

PREVALENCE OF HbsAg in CHILDREN

• Urban 6.3%

• Rural 18.5%

• Institutionalised 35.4%

MEMBRANOUS GN

• 306 Black children with NS• 43% with membranous GN

• 86.2% HBV antigens

HIV AND RENAL DISEASE

• Asymptomatic patients screened: 76– Proteinuria > 1gm: 17– Proteinuria < 1gm: 6– Microalbuminuria: 27– Haematuria: 9

• Histology– HIVAN 48%

Han et al, 2004

RRT IN SUB-SAHARAN AFRICA HD CAPD IPD TP

Namibia 7 20

Zimbabwe 59 38 4

Botswana 4 3

Sudan 200 150 300

Congo 2 30 6

Kenya 80 20 Variable ± 2/week

Table 2. Renal replacement therapy in Africa (1993 – 1996)

Country Population

(millions

GNP per capita

(US dollars)

Dialysis

(pmp)

Algeria 28.0 2170 78.5

Egypt 60.0 1000 129.3

Libya 5.1 1800 30.0

Morocco 27.0 1010 55.6

Tunisia 8.7 1260 186.5

S Africa 34.4 2560 99.0

Frequency of HD

0

10

20

30

40

50

60

70

80

90

100

Thailand Egypt Tunisia S. Africa India Pakistan Argentina Mexico Venzuala

Per

cent

of p

atie

nts

1 session/wk 2 sessions/wk 3 sessions/wk

Barsoum, 2002

USA: 283,000

Latin Am: 82,000

Europe: 317,000

India: 20,000

China: 30,000

AU/NZL: 11,000

Japan: 167,000

Schena, Kidney Int (Suppl 74), 2000

World-ESRD (1996)

PrevalenceIncidence

1,000,000 220,000

DIALYSIS PATIENTS WORLD-WIDE (1996)

10,000

South Africa2560 (25%)

United States

30

15

10$

( bi

llion

s)

2000 2005 2010

Costs

20

25

700

600

500

400

300

Pat

ient

s (

x 1,

000)

2000 2005 2010

Dialysis

Xue et al., J Am Soc Nephrol, 2001

Growth to year 2010 projected on the basis of historical data (1982-1997) by stepwise autoregression and exponential smoothing models

$

$

$

Renal replacement therapy is so costly that there is minimal probability for the vast majority of the world’s population to take advantage from it

Prevention: Tackling the problems

Diabetes

Hypertension

Glomerular Disease

LIFESTYLE MEASURES

Public education and commitment to healthSmoking

hypertensionhastens progression to kidney failure

Dietary saltObesityPrudent dietExercise

HIGH RISK GROUPS

• Identified at early stage

• Effective management at all levels

Kidney Disease Renoprotection Programmes

Locate People at riskDiabetes, Hypertension, Elderly, HIV

Initiator / InjuryProtein leakage, Proteinuria

Prevent ProgressionKDRP Programmes

ESRDPreparing people

TxDialysis

Chronic Kidney Disease

Study before PPP was startedBlood Pressure was poorly controlled

81.6%

18.4%

Controlled Uncontrolled

Percentage of controlled patients if 80% of the readings are

= or < 140/90 Gauteng Health Department Report 2000

Kidney disease detection and renoprotection programme in Johannesburg

• 11 intervention clinics

• 4 “usual” care clinics

795 pts evaluated:

35% proteinuria

25% albuminuria

10% micro-albuminuria

HBV VACCINE

• Vaccine coverage rates– 1st dose 85.4%– 2nd dose 78.2%– 3rd dose 62%

Impact of HBV vaccination on NS in children

• 1984 – 2001 119 children with HBV MN aRR 0.25/ 105

1984 – 1994 0.22 2000 – 2001 0.03

pre-vaccine post-vaccine

0 – 4 years 0.16 0.00 5 – 10 years 0.46 0.19

Bhimma et al, 2003

WHAT IS THE GLOBAL STRATEGY NEEDED IN LESS-

DEVELOPED WORLD?

Identify apparently healthy subjects at risk of developing renal and cardiovascular diseases later in life

Build regional or national prevention strategies by developing therapeutic intervention programs

PREVENTION STRATEGIES

• Public education• Free antenatal care for pregnant women

and children• Ban on smoking• Screening for hypertension and diabetes• Eradication of Schistosomiasis• HBV vaccine in EPI since 1995• Effective intervention programmes

A WORLD-WIDE STRATEGY REQUIRING INTERNATIONAL

PARTNERSHIPS

• Government ministries of health (and education)

• International Agencies

• Academic centers

• Foundations