The Footprint of Diabetes Mellitus on the Characteristics and Response to Anti-Tuberculous Therapy in Patients with Pulmonary Tuberculosis from Saudi Arabia

Figures & data

Table 1 Baseline Characteristics of the Study Population

Parameters	DM/PTB Group n = 132 (%)	Non-DM/PTB Group n = 355 (%)	χ^2	p-value
Age, years (± SD)^a	61.17 ± 11.33	50.94 ± 16.3	7.79	0.0001*
Gender
Males	84 (63.6%)	212 (59.7%)	0.62	0.46
Females	48 (36.4%)	143 (40.3%)
Nationality
Saudi	85 (64.4%)	271 (76.3%)	11.55	0.14
Egyptian	19 (14.4%)	33 (9.3%)
Filipino	15 (11.4%)	29 (8.2%)
Others	13 (9.8%)	22 (6.2%)
Occupation
Self-employed	56 (42.4%)	162 (45.6%)	16.89	0.18
Un-employed	48 (36.4%)	132 (37.2%)
Business-owner	21 (15.9%)	20 (5.6%)
Migrant-worker	5 (3.8%)	20 (5.6%)
College student	2 (1.5%)	21 (5.9%)
BMI, kg/m^2 (± SD)^a	25.15 ± 3.59	24.08 ± 3.71	2.85	0.005*
Past history of PTB	13 (9.8%)	24 (6.8%)	1.31	0.34
Contact to PTB case	90 (68.2%)	215 (60.6%)	2.38	0.14
Cigarette smoking	99 (75%)	250 (70.4%)	0.33	0.37
Alcohol drinking	22 (16.7%)	43 (12.1%)	3.9	0.23

Notes: ^aSignificance was tested using the independent samples T-test; *p <0.05 (statistically significant).

Abbreviations: DM/PTB, diabetes mellitus and pulmonary tuberculosis; n, number; χ², Pearsons Chi-Square test; SD, standard deviation; BMI, body mass index.

Table 2 Baseline Glycemic Parameters in Diabetic versus Non-Diabetic Pulmonary Tuberculosis Patients

Parameters	DM/PTB Group n = 132 (%)	Non-DM/PTB Group n = 355 (%)	95% CI	p-value
FPG (mg/dL)	210.59 ± 42.69	109.69 ± 10.98	96.08–105.73	0.0001*
2-hours PPG (mg/dL)	328.51 ± 66.38	180.8 ± 17.19	140.19–155.21	0.0001*
HbA1c%	10.58 ± 2.33%	5.09 ± 0.56%	5.23–5.75	0.0001*

Notes: *p <0.05 (statistically significant). Data are expressed as means ± standard deviation (SD).

Abbreviations: DM/PTB, diabetes mellitus and pulmonary tuberculosis; n, number; CI, confidence interval; FPG, fasting plasma glucose; PPG, postprandial plasma glucose; HbA1c, glycosylated hemoglobin.

Table 3 Clinical and Radiologic Findings of Pulmonary Tuberculosis Among Diabetic versus Non-Diabetic Patients

Parameters	DM/PTB Group n = 132 (%)	Non-DM/PTB Group n = 355 (%)	OR (95% CI)	p-value
Clinical findings
Cough	116 (87.9%)	268 (75.5%)	2.35 (1.32–4.19)	0.004*
Fever	110 (83.3%)	258 (72.7%)	1.88 (1.13–3.14)	0.01*
Night sweating	97 (73.5%)	223 (62.8%)	1.64 (1.05–2.55)	0.03*
Dyspnea	70 (53%)	96 (27%)	3.05 (2.01–4.61)	0.0001*
Weight loss	68 (51.5%)	127 (35.8%)	1.9 (1.27–2.86)	0.002*
Anorexia	59 (44.7%)	113 (31.8%)	1.73 (1.15–2.61)	0.01*
Malaise	52 (39.4%)	112 (31.5%)	1.4 (0.93–2.14)	0.1
Chest pain	43 (32.6%)	110 (31%)	1.08 (0.70–1.65)	0.74
Hemoptysis	36 (27.3%)	63 (17.7%)	1.74 (1.08–2.78)	0.02*
Pulmonary radiologic findings
Consolidation	58 (43.9%)	107 (30.1%)	1.82 (1.2–2.74)	0.005*
Cavitation	42 (31.8%)	73 (20.6%)	1.8 (1.15–2.82)	0.012*
Lower lung lesions	26 (19.7%)	51 (14.4%)	1.46 (0.87–2.46)	0.16
Nodules	20 (15.2%)	45 (12.7%)	1.23 (0.69–2.17)	0.54
Pleural effusion	13 (9.8%)	23 (6.5%)	1.6 (0.77–3.21)	0.21

Notes: *p <0.05 (statistically significant). Data are expressed as numbers and percentages.

Abbreviations: DM/PTB, diabetes mellitus and pulmonary tuberculosis; n, number; OR, odds ratio; CI, confidence interval.

Table 4 Sputum Acid-Fast Bacillus (AFB) Smear Results in This Study

Parameters	DM/PTB Group n = 132 (%)	Non-DM/PTB Group n = 355 (%)	χ^2	p-value
Baseline sputum smear results
Negative	27 (20.5%)	139 (39.2%)	18.71	0.0001*
Grade ++	69 (52.3%)	163 (45.9%)
Grade +++	36 (27.3%)	53 (14.9%)
Two months’ post-treatment smear results
Negative	58 (43.9%)	240 (67.6%)	43.32	0.0001*
Grade +	48 (36.4%)	103 (29.0%)
Grade ++	26 (19.7%)	12 (3.4%)

Notes: *p <0.05 (statistically significant). Data are expressed as numbers and percentages.

Abbreviations: DM/PTB, diabetes mellitus and pulmonary tuberculosis; n, number; χ², Pearsons Chi-Square test.

Figure 1 Kaplan–Meier plot of the time to sputum culture conversion after treatment initiation among pulmonary TB (PTB) patients with and without diabetes mellitus (DM). Kaplan–Meier curves revealed significantly longer sputum time to culture conversion into negative among DM/PTB patients (mean time: 77.55 ± 37.74 days) as compared to their non-diabetic counterparts (mean time: 54.95 ± 27.67 days). Significance was tested using the Log rank test (χ²= 43.14, p = 0.0001). Of note, 57.6% of the diabetic cohort had their sputum culture converted to negative after 2 months of anti-TB therapy, in contrast to 77.7% of the non-diabetics. *p < 0.05 (statistically significant).

Table 5 Multivariate Logistic Regression Analysis of the Predictors for Sputum Culture Conversion in This Study

Parameters	Culture Conversion	No Culture Conversion	Univariate p-value	Multivariate
				OR (95% CI)	p-value
Age group
<30 years	25 (7.1%)	6 (4.4%)		0.54 (0.2–1.42)	0.21
30–44 years	87 (24.7%)	22 (16.3%)	0.007*	0.55 (0.31–0.98)	0.45
45–60 years	121 (34.4%)	39 (28.9%)		0.53 (0.33–0.87)	0.01*
>60 years	119 (33.8%)	68 (50.4%)		–	–
Gender
Male	219 (62.2%)	77 (57%)	0.3	0.72 (0.47–1.09)	0.12
Female	133 (37.8%)	58 (43%)
DM
Yes	76 (21.6%)	56 (41.5%)	0.0001*	2.28 (1.39–3.72)	0.001*
No	276 (78.4%)	79 (58.5%)
Sputum smear grade (Baseline)
Negative	122 (34.7%)	44 (32.6%)		1.02 (0.56–1.87)	0.95
++	168 (47.7%)	64 (47.4%)	0.81	0.98 (0.56–1.73)	0.95
+++	62 (17.6%)	27 (20%)		–	–
Sputum smear grade (2 months after treatment)
Negative	228 (64.8%)	70 (51.9%)		0.93 (0.43–2.02)	0.85
+	99 (28.1%)	52 (38.5%)	0.03*	1.47 (0.67–3.26)	0.34
++	25 (7.1%)	13 (9.6%)		–	–

Note: *p <0.05 (statistically significant).

Abbreviations: DM, diabetes mellitus; OR, odds ratio; CI, confidence interval.