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DIABETES IN SUB-SAHARAN AFRICA
Dr Kaushik Ramaiya
The future burden of diabetes in sub-Saharan Africa
02468
101214161820
Amos et al, 1997 WHO, King et al,1998
WHO, Wild et al,2003
mil
lion
s
2010
2025
2030
Africa is experiencing a rapid epidemiological transition with the burden of non-communicable diseases esp. diabetes that will overwhelm the health care systems which is already overburdened by HIV/AIDS, TB and Malaria.
This is due to
• Rapid urbanization and westernization of lifestyle
• Rapidly decreasing physical activity
• Changes in dietary habits
• Ageing of the population
What is different about DM in Africa?
• Decreases survival from the disease.• Most countries do not have national diabetes
programmes. • Medications are unavailable or irregularly available
and unaffordable.• Well-structured educational programs for the patients
and health professionals are lacking..• Unequal distribution of facilities and providers.
AgeRISK FACTORS
• NON MODIFIABLE Age Ethnicity/
predisposition
• MODIFIABLE Obesity Urbanization
Physical inactivity Change in dietary
habits
Prevalence of diabetes by age group in a population of Cameroon
Mbanya JC et al
ObesityRISK FACTORS
• NON MODIFIABLE Age Predisposition
• MODIFIABLE Obesity Urbanization
Physical inactivity
Change in dietary habits
Sobngwi E, et al. Int J Obes 2002
Childhood ObesityRISK FACTORS
• NON MODIFIABLE Age Predisposition
• MODIFIABLE Obesity Urbanization
Physical inactivity
Change in dietary habits
Average percentage annual increase in urban and rural
populations, 1995-2000
RISK FACTORS
• NON MODIFIABLE Age Predisposition
• MODIFIABLE Obesity Urbanization
Physical Inactivity Change in dietary
habits
0
1
2
3
4
5
6
7
8
Cameroon Kenya Nigeria South Africa Tanzania
UrbanRural
Physical Inactivity
Men
0
20
40
60
80
100
120
< 30y 30 - 49y >= 50y
Da
ily m
inu
tes
of
wa
lk
Rural
Urban
p<0.0001
p<0.0001p<0.0001
Women
0
20
40
60
80
100
120
< 30y 30 - 49y >= 50y
Da
ily m
inu
tes
of
wa
lk
Rural
Urban
p<0.0001
p<0.0001
p<0.0001
Daily walking time in a sample of 2465 urban and rural Cameroonians (Sobngwi E, et al Int J Obes 2002)
RISK FACTORS
• NON MODIFIABLE Age Predisposition
• MODIFIABLE Obesity Urbanization
Physical Inactivity
Change in dietary habits
COUNTRY YEAR AUTHOR AGE
RANGE
INCIDEN
CE/100,000
NIGERIA 1990-1992 Osa 7.2
SUDAN 1987-1990 Elamin 0-14 5.7-10.1
TANZANIA 1982-1991 Swai 0-15 15-19
1.5 3.4
ZANZIBAR 1989-1992 Mohamed 0-19 2.1
TUNISIA 1991-1993 Nagati 0-20 5.4
LIBYA 1989-1992 1991-1995
Jamal Kadiki
0-18 0-19
5.2 8.1
ALGERIA 1979-1992 1993-1997 1993-1997
Bessaoud Malek Malek
0-14 0-14 15-19
7.2 4.8 6.5
TYPE 1 DIABETESTYPE 1 DIABETES:: INCIDENCE
5.8
7.7
10.2
8.1
0
2
4
6
8
10
12
1987 1988 1989 1990
INCIDENCE/100,000 of Type 1 diabetes in Sudan (El Amin et al.)
Type 1 DM in Africa- Clinical characteristics of Type 1 diabetes in Africa Patients
Country N Age group (yr)
M:F Age of onset (yr)
Peak age of onset (yr)
Duration of diabetes (yr)
South Africa Durban 86 <35 1:1.2 23.5 21-30 3.8 Johannesburg 176 <35 1:1.3 22.0 22-23 4.0
Tanzania 272 All
ages 2:1 29.4 15-19 New
Ethiopia 431 All ages
1:1.1 21.4 M 18.1 F
20-25 M 10-17 F
Motala AA et al. Diabetes International, July 2000.
Type 2 DM in Africa• Data
• increasing but limited• Not rare
• low in rural areas• moderate in rural and urban areas with development• high in urban areas
• Urban > Rural• IGT
• early stage of epidemic• Increasing in same population• Ethnicity• Modifiable risk factors
SUMMARY OF CURRENT PREVALENCE OF TYPE 2 DIABETES
• Rural Sub Saharan Africa 1 – 3.5%
• Urban Sub Saharan Africa 3 – 7.7%
• Republic of South Africa 4.8 – 8.0%
• Maghrebian countries 6.3 – 9.3%
• Indian origin populations 8.6 – 13.3%
Complications of diabetes
• Increasing prevalence of diabetes and their complications in Sub-saharan Africa are a major drain on health resources in addition to physical and social impact on an individual and community
Acute complications of diabetes:
• Diabetic ketoacidosis
• Hyperosmolar non-ketotic coma
• Hypoglycaemia
Diabetic ketoacidosis
• Common emergency• High mortality 25% in Tanzania, 33% in
Kenya • Contributing factors:
– Lack of insulin availability– Delay in diagnosis– Misdiagnosis– Economics– Poor healthcare system – infections
Hyperosmolar non-ketotic coma:
• Complication of type 2 diabetes• Less common • Accounts for about 10% of all hyperglycaemic
emergencies (Zouvanis et al, 1987)• Contributing factors:
– Infections– Non-compliance– First presentation
• Mortality high – 44% - studies from South Africa (Rolfe et al, 1995) – patients usually elderly and have other major illness
Hypoglycaemia
• Serious complication of OHA therapy • In South Africa (Gill & Huddle,1993) 33% of cases
associated with sulphonylurea treatment• Other precipitating causes:
– Missed meal (36%)
– Alcohol (22%)
– GI upset (20%)
– Inappropriate treatment
year country prevalence (%)
1988 Zambia 34
1993 Ethiopia 13
1995 South Africa 52
1996 Cameroon 37
1996 Cameroon 37
1996 Burkina Faso 16
1997 South Africa 37
1997 South Africa 55
1997 Ethiopia 36
Microvascular complications of diabetesRETINOPATHY
RETINOPATHY
• In South Africa, at diagnosis, 21-25% of type 2 diabetes and 9.5% of type 1 diabetes have retinopathy (Kalk et al,1997).
• ? Genetic predisposition – africans more affected
• Poor/inadequate access to healh care leading to inadequate control of blood glucose and blood pressure.
year country prevalence (%)
1996 Kenya 41*
1996 Burkina Faso 25
1996 Cameroon 46*
1997 South Africa 37
1997 Ethiopia 33
*microabuminuria
Microvascular complications of diabetes NEPHROPATHY
NEPHROPATHY
• Diabetes contributes to 35% of all patients admitted to dialysis unit (Diallo et al,1997)
• In South African series, 50% of all causes of mortality in type 1 diabetes was due to renal failure (Gill, Huddle & Rolfe, 1995)
year country prevalence (%)
1988 Zambia 31
1991 Ethiopia 36
1991 Sudan 31.5
1994 Tanzania 25
1995 South Africa 42
1997 South Africa 28
Microvascular complications of diabetesNEUROPATHY
NEUROPATHY
• Prevalence varies widely depending on method used.
• Poor glycaemic control and inadequate foot care are risk factors for diabetic foot.
Epidemiology of Diabetic Foot(Abbas ZG)
40-60% of all non-traumatic amputations 85% of diabetes related lower extremity
amputations The prevalence of foot ulcer is 4-15% of
diabetes population
MACROVASCULAR COMPLICATIONS OF DIABETES
COMPLICATION COUNTRY YEAR PREVALENCE (%)
Lower Limbs Vascular Disease
(PVD)
Senegal 1994 28
South Africa
1997 8
Sudan 1995 10
Tanzania 1997 12
Coronary Artery Disease (CVS)
Bukina Faso 1996 8
Uganda 1996 5
Cerebrovascular Disease
Sudan 1995 5
Zambia 1988 1
Diabetes - Clinical course• ETHIOPIA Causes
of death in 100 Ethiopian diabetic patients 1976 - 1983.• At death:- 45 % of
patients below age 50 years 46 % below 10 years of diabetic duration
• Causes of death:-Metabolic 47 % Renal Failure 26 % Infective
12 % Cirrhosis 10 %Stroke 8 % Other
12 % Not known15 %
•Lester FT. Ethiopian Med J 1984; 2: 61-68
Diabetes - Clinical CourseSouth Africa
Number recruited 88 patients Lost to follow-up - moved out
24 patients
Mean age at follow-up 32 years Mean duration Type 1 DM (at follow-up)
14 years
Mortality 10/64 (16 %) Causes of death Nephropathy 5
Hypoglycaemia 2 Ketoacidosis 2
Ten year follow-up study of Type 1 DM patients in Soweto, South Africa, 1982-92.
Gill GV et al. Diabetic Med, 1995; 12:546-550
Clinical course of DiabetesTanzania (Dar es Salaam)
Clinical course of diabetes in the 1250 newly diagnosed diabetic patients with a follow-up period 22-94 months (to April 1989). n 5 year survival
rates* Insulin requiring DM
272
59.5 %
Non-insulin requiring DM
825 81.8 %
Uncertain type DM
153 43.0 %
*known and probable deaths
Insulin / OHA costs
• Tanzania (1989-90):-• Average annual direct cost of diabetes care
US $ 287.00 IRDM US $ 103.00 NIDDM
• Purchase of insulin accounted for US $ 156.00 (68.2%) of the average annual outpatient costs for IRDM.
• OHA accounted for US $ 29.30 (42.5%) of the average annual outpatient costs for NIDDM.
Chale SS et al. For Med J 1992; 304: 1215-8
Costs of treatment
• In Cameroon (Nkegoum, 2002) in the year 2001:– Average direct medical cost of treating a
patient with diabetes was USD 489.– 56% -hospital admission– 33.5% - anti-diabetic drugs– 5.5% -laboratory tests– 4.5% on consultation fee.
Indirect cost of diabetes (Tanzania 1989-90)
Future Healthy Life Days (HLDs) lost per patient with diabetes during the 8 years of follow-up.
IRDM(n=3626)
%
NIDDM(n=2390)
%
Uncertain(n=1974)
%
Overall(n=4100)
%
Premature death 55.1 39.7 96.8 69
Disability before death 0.5 3.9 0.4 1
Chronic disability 43.3 55.7 2.4 29
Acute Illness 1.1 0.6 0.4 1
Chale SS. A study of the Economic Costs of Diabetes Mellitus in Tanzania in 1989/90. UDSM
Reason for lost days
This increasing burden is against a background of decreasing resources.
Therefore primary prevention must be the cornerstone of policies aimed at combating these lifestyle related diseases.
Prevention StrategiesProblems in Africa
• Mortality– Poorly skilled or inadequate providers– Delay - attention– Drugs – availability
- affordability• Complications
awareness facilities– detection
- monitoring– economics
Barriers to Quality care• Irregular supply of medicines (including insulin)
• Inadequate health-care infrastructure and disproportionate distribution of the facilities
• Affordability
• Lack of adequate training and retraining of health care providers
• Lack of education to the people living with diabetes & their families
• Differing government priorities
IDF AFRICA REGION - RESPONSE
• Diabetes Practice Guidelines.
• Diabetes Education Training manual
• African Declaration on Diabetes
• Training
• Strengthening national diabetes associations
• Research / data