Tackling the epidemic of chronic noncommunicable disease in sub Saharan Africa: established priorities and new concerns Nigel Unwin Institute of Health and Society Newcastle University
Overview and acknowledgements Investigations into burden and health care coverage Some implications for research New concerns links between infectious and NCDs Cameroon JC Mbanya E Sobngwi A Paschal Tanzania D McLarty F Mugusi H Kitange S Rashid UK George Alberti Philip Setel David Whiting
Adult Morbidity and Mortality Project (AMMP) Annual or biannual censuses, key informant system to identify deaths and verbal autopsy with next of kin
Deaths from NCDs in women (15-59 years), in 3 areas of Tanzania and EMEs. 90 80 70 60 50 40 30 20 Percentage of all deaths Rate % 10 Dar Moro Rural Hai EMEs 0
Deaths from NCDs in women (15-59 years), in 3 areas of Tanzania and EMEs. Death rates 300 250 200 150 100 50 90 80 70 60 50 40 30 20 10 Percentage of all deaths Rate % 0 Dar Moro Rural Hai EMEs 0 Data for year 2000
Age-specific death rates from stroke in England and Wales 10000 Log rate per 100,000 1000 100 10 M E&W W E&W 1 25-34 35-44 45-54 55-64 65-74 75-84 85+ Age
Age-specific death rates from stroke in England and Wales and Dar es Salaam 10000 Log rate per 100,000 1000 100 10 M Dar M E&W W Dar W E&W 1 25-34 35-44 45-54 55-64 65-74 75-84 85+ Age
Prevalence (%) of Diabetes - fbg > 6.1 mmol/l Women Men 16 16 14 14 12 12 10 10 8 6 Dar Hai 8 6 Dar Hai 4 4 2 2 0 15-34 35-54 55+ 0 15-34 35-54 55+ Age group
Prevalence (%) of BMI > 25 Women Men 60 60 50 50 40 40 30 20 Dar Hai 30 20 Dar Hai 10 10 0 15-34 35-54 55+ 0 15-34 35-54 55+ Age group
Care for Diabetes in Dar es Salaam 80% to 90% undiagnosed In a pop based survey of 170 diagnosed: 28% of diagnosed claim to attend clinic reg. Health services provide care for ~3% of all DM But 20% of these missed most recent appt. 50% to 60% had not tested blood glucose in previous month 3% of those diagnosed were well-controlled (HBA1c < 7%)
Key research themes Surveillance Addressing the need for better data Treatment Improving the effectiveness and efficiency and currently expended resources Prevention Approaches appropriate to the social, cultural and economic conditions (Medical logic => social logic)
DCPDC Cost saving diabetes interventions HBA1c control < 9% BP control < 160/95 Foot care examination and education
New concerns Co-morbidity between infectious and chronic non-communicable diseases Potential public health importance Awareness raising on impact of NCDs Diabetes and TB HIV treatment and diabetes/cvd risk
TB and Diabetes In the past, a relationship between TB and diabetes was recognised (TB-DM clinics in 1950s UK) Little recognition of relationship in current policy guidance May have implications for management e.g. case finding and diabetes treatment among TB patients
Possible mechanisms Diabetes increases risk TB infection Diabetes causes progression from latent to active disease Reverse causality TB may worsen glycaemic control (some medications have hyperglycaemic effects)
Review of TB-DM studies Literature review of studies assessing TB DM association, 1995-2007 9 studies (1995-Jan 2007) 1 prospective cohort, 6 case-control (3 based on routine data), 2 further analyses using routine data sources Geographical location 2 from US, and 1 each from the UK, Mexico, Russia, Korea, Indonesia, India, Canada Stevenson et al. Chronic Illness Vol. 3 No. 3, 228-245 (2007)
Results of review Adjusted ORs or RR
Pulmonary TB and diabetes in India attributable risk estimates Data sources: TB incidence from WHO estimates based on notifications from the Revised National TB Control Programme for India Prevalence of diabetes from Prevalence of Diabetes in India Study (PODIS) involving >18,000 adults in rural and urban areas Age specific relative risk from study of >80,000 Korean civil servants (Kim et al. 1995) Source: Stephenson et al BMC Public Health 2007, 7:34
Pulmonary TB and diabetes in India attributable risk estimates (2) TB incidence attributable to diabetes in adults (25 years +): 15% of all pulmonary TB 20% smear positive TB Over a 5 th of excess in urban areas Diabetes in people with TB 18% of all cases of pulmonary TB have diabetes 24% of those with smear positive TB have diabetes Source: Stephenson et al BMC Public Health 2007, 7:34
Impact of diabetes in TB Increased mortality Longer to sputum negativity Increased relapsed Stevenson et al. Chronic Illness Vol. 3 No. 3, 228-245 (2007)
Implications of DM-TB for Africa TB 363/100,000 per year 2.8 million new cases per year 4.2 million prevalent cases 22% HIV positive Diabetes Low prevalence in rural areas (1%) High and rising prevalence in urban areas (5-10%)
TB-DM Research needs in Africa Strength of the association Prevalence of DM and pre diabetes in TB Impact of DM and pre diabetes on TB outcomes
HIV, antiretroviral therapy and risk of Diabetes and Cardiovascular Disease
Influence of HIV related factors on metabolic risk Triglycerides with some ARTs e.g. efavirenz/stavudine Insulin resistance with some ARTs e.g. NRTIs Lipoatrophy NRTIs (esp stavudine), NNRTIs, PIs Diabetes with PIs,? others
Impact of ARTs on metabolic risk in Africa Virtually no published data Recent study from Cameroon Sobngwi/Johnstone/Unwin
Study participants by length of time on treatment Group allocation based on months on treatment P ro p o rti o n 35 30 25 20 15 10 5 0 Group Frequency Percentage
Mean waist-hip by treatment group 0.93 0.92 Mean waist-hip 0.91 0.9 0.89 0.88 0.87 0.86 0.85 <12 <24 <36 <48 <60 mean 0.84 0.83 Relationship independent of age, sex and BMI
ART need and coverage in Africa in 2005, research needs Need: 4.7 million Coverage: 310,000 (17%) Research Define metabolic consequences? need for preventive interventions
In summary Place of NCDs on overall disease burden Research agenda, based largely implementing knowledge on treatment and prevention into an African setting Links between NCDs and infectious disease New research needs
Thank you