Burden and associated phenotypic characteristics of tuberculosis infection in adult Africans with diabetes: a systematic review

Diabetes mellitus (DM) increases the risk of developing tuberculosis infection (TBI). However, the evidence on the burden and phenotypic characteristics of TBI in African patients with DM is limited. This study aimed to determine the prevalence and characterisation of TBI in native African patients living with DM. We searched PubMed, EMBASE, and African Journals Online for original studies reporting information on the prevalence and characteristics of TBI in adult Africans with DM. A forest plot was used to describe the pooled prevalence estimate of TBI and the corresponding 95% confidence intervals (CI). Six studies conducted in four African countries involving 721 participants with DM were included in this systematic review. The pooled prevalence estimate of TBI was 40% (95% CI 20–60%, I2 = 98.52%, p < 0.001). Age ≥ 40 years and glycated haemoglobin levels independently predicted TBI positivity in patients with DM in three studies. Africans with DM have a high prevalence of TBI, especially those who are older or with poorly controlled diabetes. This justifies the need for studies to explore how to screen and manage TBI to avert the progression to active TB disease.


5-6
Selection process 8 Specify the methods used to decide whether a study met the inclusion criteria of the review, including how many reviewers screened each record and each report retrieved, whether they worked independently, and if applicable, details of automation tools used in the process.

6
Data collection process 9 Specify the methods used to collect data from reports, including how many reviewers collected data from each report, whether they worked independently, any processes for obtaining or confirming data from study investigators, and if applicable, details of automation tools used in the process.

6-7
Data items 10a List and define all outcomes for which data were sought.Specify whether all results that were compatible with each outcome domain in each study were sought (e.g. for all measures, time points, analyses), and if not, the methods used to decide which results to collect.

10b
List and define all other variables for which data were sought (e.g.participant and intervention characteristics, funding sources).Describe any assumptions made about any missing or unclear information.

7
Study risk of bias assessment 11 Specify the methods used to assess risk of bias in the included studies, including details of the tool(s) used, how many reviewers assessed each study and whether they worked independently, and if applicable, details of automation tools used in the process.

7
Effect measures 12 Specify for each outcome the effect measure(s) (e.g.risk ratio, mean difference) used in the synthesis or presentation of results.

7
Synthesis methods 13a Describe the processes used to decide which studies were eligible for each synthesis (e.g.tabulating the study intervention characteristics and comparing against the planned groups for each synthesis (item #5)).

7-8
13b Describe any methods required to prepare the data for presentation or synthesis, such as handling of missing summary statistics, or data conversions.

7-8
13c Describe any methods used to tabulate or visually display results of individual studies and syntheses.

7-8
13d Describe any methods used to synthesize results and provide a rationale for the choice(s).If meta-analysis was performed, describe the model(s), method(s) to identify the presence and extent of statistical heterogeneity,

Section and Topic
Item # Checklist item Page where item is reported and software package(s) used.
13e Describe any methods used to explore possible causes of heterogeneity among study results (e.g.subgroup analysis, meta-regression).

8
13f Describe any sensitivity analyses conducted to assess robustness of the synthesized results.

Not done
Reporting bias assessment 14 Describe any methods used to assess risk of bias due to missing results in a synthesis (arising from reporting biases).

8
Certainty assessment 15 Describe any methods used to assess certainty (or confidence) in the body of evidence for an outcome.

Study selection
16a Describe the results of the search and selection process, from the number of records identified in the search to the number of studies included in the review, ideally using a flow diagram.

8
16b Cite studies that might appear to meet the inclusion criteria, but which were excluded, and explain why they were excluded.

8
Study characteristics 17 Cite each included study and present its characteristics.

8-9
Risk of bias in studies 18 Present assessments of risk of bias for each included study.9

Results of individual studies
19 For all outcomes, present, for each study: (a) summary statistics for each group (where appropriate) and (b) an effect estimate and its precision (e.g.confidence/credible interval), ideally using structured tables or plots.

10-11
Results of syntheses 20a For each synthesis, briefly summarise the characteristics and risk of bias among contributing studies.9 20b Present results of all statistical syntheses conducted.If meta-analysis was done, present for each the summary estimate and its precision (e.g.confidence/credible interval) and measures of statistical heterogeneity.If comparing groups, describe the direction of the effect.23d Discuss implications of the results for practice, policy, and future research.14

Registration and protocol
24a Provide registration information for the review, including register name and registration number, or state that the review was not registered.

5
24b Indicate where the review protocol can be accessed, or state that a protocol was not prepared.
Protocol was not prepared 24c Describe and explain any amendments to information provided at registration or in the protocol.

None
Support 25 Describe sources of financial or non-financial support for the review, and the role of the funders or sponsors in the review.

Item
of all investigations of possible causes of heterogeneity among study results.Not done 20d Present results of all sensitivity analyses conducted to assess the robustness of the synthesized results.Not done Reporting biases 21 Present assessments of risk of bias due to missing results (arising from reporting biases) for each synthesis assessed.NA Certainty of evidence 22 Present assessments of certainty (or confidence) in the body of evidence for each outcome assessed.10 DISCUSSION Discussion 23a Provide a general interpretation of the results in the context of other evidence.11-13 23b Discuss any limitations of the evidence included in the review.13 23c Discuss any limitations of the review processes used.13

Table 2 . Risk of bias Assessment of the studies Risk of bias item and Criteria for answers Agha et al 2020 Kazibwe et al 2023 Smith et al 2022
Report which of the following are publicly available and where they can be found: template data collection forms; data extracted from included studies; data used for all analyses; analytic code; any other materials used in the review.
* The