Transcript 33571

DIABETES IN SUB-SAHARAN
AFRICA
Dr Kaushik Ramaiya
millions
The future burden of diabetes in sub-Saharan
Africa
20
18
16
14
12
10
8
6
4
2
0
2030
2025
2010
Amos et al, 1997
WHO, King et al,
1998
WHO, Wild et al,
2003
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.
RISK FACTORS
Age
• 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
RISK FACTORS
Obesity
• NON MODIFIABLE
 Age
 Predisposition
• MODIFIABLE
 Obesity
 Urbanization
 Physical
inactivity
 Change in dietary
habits
Sobngwi E, et al. Int J Obes 2002
RISK FACTORS
• NON MODIFIABLE
 Age
 Predisposition
• MODIFIABLE
 Obesity
 Urbanization
 Physical
inactivity
 Change in dietary
habits
Childhood Obesity
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
8
7
6
5
Urban
Rural
4
3
2
1
0
Cameroon
Kenya
Nigeria
South Africa
Tanzania
RISK FACTORS
Physical Inactivity
Women
 Age
 Predisposition
• MODIFIABLE
Daily minutes of walk
• NON MODIFIABLE
100
p<0.0001
p<0.0001
Rural
80
Urban
60
40
20
0
< 30y
 Obesity
 Urbanization
30 - 49y
>= 50y
Men
120
Daily minutes of walk
 Physical
Inactivity
 Change in
dietary habits
p<0.0001
120
100
80
p<0.0001
p<0.0001
p<0.0001
Rural
60
Urban
40
20
0
< 30y
30 - 49y
>= 50y
Daily walking time in a sample of 2465 urban and rural
Cameroonians (Sobngwi E, et al Int J Obes 2002)
TYPE 1 DIABETES: INCIDENCE
COUNTRY
NIGERIA
YEAR
AUTHOR
AGE
RANGE
1990-1992 Osa
INCIDEN
CE/100,0
00
12
10.2
10
7.2
8
SUDAN
1987-1990 Elamin
0-14
8.1
5.7-10.1
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 Jamal
1991-1995 Kadiki
0-18
0-19
5.2
8.1
ALGERIA
1979-1992 Bessaoud
1993-1997 Malek
1993-1997 Malek
0-14
0-14
15-19
7.2
4.8
6.5
TANZANIA 1982-1991 Swai
7.7
6 5.8
4
2
0
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
M:F
group
(yr)
Age of
onset
(yr)
Peak
age of
onset
(yr)
Duration
of
diabetes
(yr)
Johannesburg
86
176
<35
<35
1:1.2
1:1.3
23.5
22.0
21-30
22-23
3.8
4.0
Tanzania
272
2:1
29.4
15-19
New
Ethiopia
431
All
ages
All
ages
1:1.1
21.4 M
18.1 F
20-25 M
10-17 F
South Africa
Durban
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
Microvascular complications of diabetes
RETINOPATHY
year
1988
1993
1995
1996
1996
1996
1997
1997
1997
country
prevalence
(%)
Zambia
34
Ethiopia
13
South Africa 52
Cameroon
37
Cameroon
37
Burkina Faso 16
South Africa 37
South Africa 55
Ethiopia
36
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.
Microvascular complications of diabetes
NEPHROPATHY
year
country
1996
Kenya
1996
Burkina Faso 25
1996
Cameroon
46*
1997
South Africa
37
1997
Ethiopia
33
*microabuminuria
prevalence
(%)
41*
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)
Microvascular complications of diabetes
NEUROPATHY
year
country
1988
Zambia
prevalence
(%)
31
1991
Ethiopia
36
1991
Sudan
31.5
1994
Tanzania
25
1995
South Africa
42
1997
South Africa
28
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
Bukina Faso
1996
8
Uganda
1996
5
Sudan
1995
5
Zambia
1988
1
Coronary Artery
Disease (CVS)
Cerebrovascular
Disease
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 known
15 %
•
Lester FT. Ethiopian Med J 1984; 2: 61-68
Diabetes - Clinical Course
South Africa
Ten year follow-up study of Type 1 DM patients in
Soweto, South Africa, 1982-92.
Number recruited
Lost to follow-up
- moved out
Mean age at follow-up
Mean duration Type 1 DM (at
follow-up)
Mortality
Causes of death
Gill GV et al. Diabetic Med, 1995; 12:546-550
88 patients
24 patients
32 years
14 years
10/64 (16 %)
Nephropathy
5
Hypoglycaemia 2
Ketoacidosis
2
Clinical course of Diabetes
Tanzania (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
Reason for lost days
Chale SS. A study of the Economic Costs of Diabetes Mellitus in Tanzania in 1989/90. UDSM
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 Strategies
Problems 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