Prevalence and Associated Factors of Diabetes Mellitus Type 2 Among Tuberculosis Patients in Muscat, Oman, 2017-2020

Diabetes mellitus (DM) and tuberculosis (TB) are global public health concerns and leading causes of mortality and morbidity worldwide. Coinfection is known to complicate TB control and outcomes. However, there is no national study regarding the prevalence of DM among TB patients in Oman. The objective of the current study was to assess the prevalence of DM and its associated factors among TB patients in Muscat, Oman.

We conducted an analytical cross-sectional study using secondary data from the electronic system of the Ministry of Health (Al-Shifa 3+). It includes all adult TB patients in Muscat, from 2017-2020. Sociodemographic data, clinical characteristics, and comorbidities of TB patients were collected. SPSS with 95% CI and ^p-value ≤ 0.05 was used for statistical analysis.

Of 426 TB cases, the prevalence of DM was 27.0%. The associated factors of DM were age group 40-54 years (odds ratio (OR) = 9.08, 95% CI: 4.16-19.84) and ≥ 55 years (OR = 11.35, 95% CI: 5.19-24.82), male (OR = 2.35, 95% CI: 1.45-3.81), being married (OR = 13.18, 95% CI: 4.72-36.84), being employed (OR = 2.30, 95% CI: 1.19-4.47), and Bangladeshi (OR = 7.08, 95% CI: 2.50-20.12) or Indian (OR = 6.14, 95% CI: 2.40-15.70) nationality. The absence of Bacillus Calmette-Guérin scar (OR = 2.06, 95% CI: 1.19-3.56), death (OR = 7.08, 95% CI: 1.26-7.82), and cured after TB treatment (OR = 3.02, 95% CI 1.71-5.31) showed significant association. Also, smoking (OR = 2.93, 95% CI: 1.81-4.76), drinking alcohol (OR = 1.79, 95% CI: 1.10-2.91), hypertension (OR = 10.45, 95% CI: 5.29-20.64), heart disease (OR = 8.50, 95% CI: 1.69-42.77), and renal disease (OR = 4.84, 95% CI: 1.71-13.64) contributed to the study's comorbidities. Old age (adjusted OR = 2.30, 95% CI: 1.72-3.06) and hypertension (adjusted OR = 5.21, 95% CI: 2.28-11.87) were found to be predictors of DM among TB patients.

The prevalence of DM among TB patients in Muscat is high. Integrated systematic bidirectional TB-DM screening is needed. Furthermore, special attention is required for associated factors when managing these comorbidities.