Note: If you do not see the map please try this link
Access the complete complete version of document The Dual Threat of Diabetes and Tuberculosis in the Americas
Diabetes and tuberculosis are two chronic diseases with high impact in populations of developing countries. The risk for tuberculosis is augmented by impaired host defense in individuals, such as those with HIV and diabetes. Objective:estimate the number of cases of TB associated with DM (TB/DM) in the Americas in 2008.
The number of cases of tuberculosis related to diabetes by age and gender were estimated by calculating the Population Attributable Fraction (PAF). Estimates of the prevalence of diabetes and the incidence of tuberculosis were extracted from the IDF Diabetes Atlas and the WHO Global TB Database respectively. The incidence of TB/DM is presented in number of cases per 100,000 by country. Breakdowns by age, gender, country income and geographic sub regions are also presented.
Overall 26 countries from the Americas were included in the analysis, accounting for some 528 million people of 25-79 years of age. The incidence of TB/DM was estimated at 31,411 (18, 495-53,352) cases (5.9 X 100,000 population). The risk varied among countries, with the highest risk observed in Haiti (59.3 per 100,000), and the lowest in Puerto Rico (0.9 per 100,000).
Diabetes Mellitus was estimated to be a substantial contributor to the burden of tuberculosis in the Americas Region in 2008. Because of the increased risk for tuberculosis, diabetes may contribute to the resurgence of tuberculosis in areas where it is currently under control and may impact negatively its control. It is recommended that tuberculosis screening is routinely conducted among those with diabetes especially those with uncontrolled diabetes.
Diabetes Mellitus (DM) affects 55 Million people in the Americas and its prevalence is expected to increase to 83 Million by 2030[i]. The diabetes epidemic is driven by a similar increase in the prevalence of obesity (Body Mass Index, BMI?30 Kg/m2) which is a direct consequence of hyper-caloric diet and lack of physical activity. Diabetes increases the risk of cardiovascular diseases, terminal kidney disease, blindness and amputations. People suffering from diabetes require continuous care and may face premature mortality from its complications if not managed well.
Tuberculosis (TB) continues affecting millions of people worldwide, despite the widespread availability of effective treatment for many years. In the Americas approximately 280,000 people are affected by all forms of tuberculosis every year[ii]. Most cases of tuberculosis are diagnosed in low-middle income countries and often concentrated in endemic areas with poor living conditions. The risk for tuberculosis is augmented by impaired host defense in individuals, such as those with HIV and diabetes[iii],[iv], [v].
In Mexico, the investigation of a national representative sample of 2,716 smear positive cases of TB showed that overall 22% of the total sampled cases were also persons with diagnosed diabetes[vi]. Another recent study showed that the prevalence of TB among 345 persons with diabetes under care was 1.5%, and half of them were asymptomatic cases of TB [vii]. In this study, those with diabetes were screened for tuberculosis with 3 sputum smear and monitored for diabetes control with one hemoglobin A1 (HbA1c) in Jalisco, Mexico. All cases of TB in this study were diagnosed among those with poorly controlled diabetes. A recent analysis of the impact of diabetes on the incidence of tuberculosis indicated that in India, diabetes accounted for 14.8% of cases of pulmonary tuberculosis and 20.2% of smear positive tuberculosis[viii].
Giving the rising public health importance of the DM TB co morbidity and its potential costly impact on society, PAHO conducted an analysis to better document the number of cases of TB associated with DM (TB/DM) in the Americas in 2008.
MethodData were extracted from the sources summarized in Table 1. Analyses were limited to adult population of 25 years of age and older, as estimates of the diabetes prevalence and the relative risks of incident tuberculosis associated with diabetes were available for this age group only. Read more...
Overall 26 countries from the Americas were included in the analysis, accounting for some 528 million people of 25-79 years of age. Table 2 shows the prevalence of diabetes and the incidence of TB by country. Read more...
Incidence of Tuberculosis
The overall incidence of tuberculosis for the Americas in 2008 was estimated in 38.7 per 100,000 population (204,424 cases), with the highest rate reported for Haiti followed by Bolivia and Guyana, all three countries with incidence of more than 172 per 100,000 (Figure1). The lowest rate was found in Puerto Rico, followed by Canada and Uruguay, all with less than 7 cases per 100.000. The estimated number of cases of TB was much higher among males than among females (Figure 2). Male to female (M:F) ratio in the risk for tuberculosis was the highest in Jamaica where four men for every one women was estimated to have TB. The lowest M:F ratio was found in Haiti where men and women had almost the same risk. Read more...
Prevalence of Diabetes
The prevalence of diabetes was estimated in 10.3 % (54 millions people) with the highest risk by country reported in Puerto Rico followed by the United States and Trinidad and Tobago, all with more than 13% of the population 25-79 years of age. The smallest risk was estimated in Paraguay with 5%. Prevalence of diabetes increases with age in both men and women. Among men and women the prevalence of diabetes is comparable within each age group. Read more...
Incidence of Tuberculosis Associated to Diabetes
The incidence of TB/DM was estimated at 5.9 X 100,000 population (31,411 cases, with lower and upper bounds estimated at 18,495 and 53,352 respectively). The incidence varied among countries with the highest figure observed in Haiti with 59.3 per 100,000, and the lowest in Puerto Rico with 0.9 per 100,000. Read more...
The lack of complete data is a limitation of this analysis. In the first place, data sources used for the prevalence of diabetes came from estimates produced by the International Diabetes Federation and not from real prevalence studies, which are not available for most countries in the Americas. Secondly, the WHO data on the incidence of tuberculosis is not desegregated by age and sex and therefore the estimates were calculated using the distribution by age and sex of smear-positive tuberculosis. Read more...
Conclusions and recommendations
Diabetes mellitus was a substantial contributor to the burden of tuberculosis in the Americas Region in 2008, accounting for an estimated 31,411 cases or 15.4% of the total number of cases of tuberculosis. Read more...
It is recommended that tuberculosis screening is routinely conducted among those with diabetes especially those with uncontrolled diabetes. Control of diabetes mellitus should be undertake as a strategy for decreasing the burden of tuberculosis. Read more...