Epidemiology of tuberculosis in Saudi Arabia following the implementation of end tuberculosis strategy: Analysis of the surveillance data 2015-2019

Article Figures & Data

Table 1

- Yearly incidence of tuberculosis in Saudi Arabia from 2015-2019.

Year	Number of cases	Total population^{^*}	Incidence risk per 100,000	Change (%)^{^†}	Reference WHO milestones (4-5% annual decrease)
2015	3345	31,717,676	10.55 (10.19-10.90)	-	10.55
2016	2993	32,443,443	9.23 (8.89-9.56)	-12.5%	10.02-10.13
2017	2962	33,101,183	8.95 (8.63-9.27)	-3.0%	9.52-9.72
2018	3359	33,702,757	9.97 (9.63-10.30)	+11.4%	9.05-9.33
2019	3003	34,268,529	8.76 (8.45-9.08)	-12.1%	8.59-8.96

↵^* Denominators used estimates provided by the World Bank data.
↵^† The change (%) is calculated as follows: 100 * (year’s rate - previous year’s rate) / previous year’s rate. For example, the change rate in 2016=100 * (9.23-10.55) / 10.55= -12.5%, which corresponds to a 12.5% decrease in the incidence from 2015-2016. WHO: World Health Organization

Table 2

- Regional distribution of incident cases of tuberculosis in Saudi Arabia from 2015-2019.

Provinces	Total (N=15662)	2015 (n=3345)	2016 (n=2993)	2017 (n=2962)	2018 (n=3359)	2019 (n=3003)	P-values
Makkah	6317 (40.3)	1345 (40.2)	1201 (40.1)	1097 (37.0)	1435 (42.7)	1239 (41.3)	<0.001^{^*}
Riyadh	3855 (24.6)	846 (25.3)	794 (26.5)	798 (26.9)	770 (22.9)	647 (21.5)
Eastern Province	1545 (13.6)	270 (8.1)	258 (8.6)	279 (9.4)	329 (9.8)	409 (13.6)
Asir	547 (3.9)	121 (3.6)	100 (3.3)	96 (3.2)	113 (3.4)	117 (3.9)
Jazan	1604 (9.0)	306 (9.1)	292 (9.8)	351 (11.9)	384 (11.4)	271 (9.0)
Madinah	705 (4.5)	176 (5.3)	130 (4.3)	128 (4.3)	135 (4.0)	136 (4.5)
Al-Qassim	285 (1.8)	88 (2.6)	57 (1.9)	68 (2.3)	38 (1.1)	34 (1.1)
Tabuk	180 (1.1)	41 (1.2)	39 (1.3)	42 (1.4)	24 (0.7)	34 (1.1)
Hail	91 (0.6)	23 (0.7)	21 (0.7)	16 (0.5)	17 (0.5)	14 (0.5)
Najran	197 (1.3)	51 (1.5)	40 (1.3)	30 (1.0)	45 (1.3)	31 (1.0)
Al Jawf	130 (0.8)	30 (0.9)	16 (0.5)	26 (0.9)	30 (0.9)	29 (0.9)
Al-Baha	118 (0.8)	33 (1.0)	21 (0.7)	14 (0.5)	24 (0.7)	26 (0.9)
Northern Borders	88 (0.6)	15 (0.4)	24 (0.8)	17 (0.6)	15 (0.4)	17 (0.6)

Values are presented as numbers and precentages (%). The Chi-square test was used.

Table 3

- Incidence risk of tuberculosis in Saudi Provinces, per 100,000 of the population.

Provinces	2015	2016	2017	2018	2019
Makkah	16.13	14.40	12.79	16.30	13.72
Riyadh	10.88	9.91	9.69	9.12	7.47
Eastern Province^{^*}	5.80	5.39	5.68	6.54	7.94
Asir^{^*}	5.72	4.61	4.33	5.00	5.07
Jazan	20.44	19.02	22.36	23.95	16.55
Madinah	8.69	6.24	5.99	6.17	6.07
Al-Qassim	6.50	4.10	4.78	2.61	2.28
Tabuk^{^*}	4.71	4.37	4.61	2.58	3.58
Hail	3.44	3.06	2.28	2.37	1.91
Najran	9.18	7.02	5.15	7.55	5.09
Al Jawf^{^*}	6.18	3.21	5.10	5.76	5.45
Al-Baha^{^*}	7.24	4.50	2.93	4.99	5.23
Northern Borders^{^*}	4.27	6.67	4.63	4.00	4.44

Values are presented as precentages (%).

↵^* Provinces showing initial decrease in the incidence, followed by an increase. Incidence was calculated with respect of the number of populations in the respective year for each province. Values are number of cases per 100000 of population.

Table 4

- Yearly trends of demographic characteristics of incident tuberculosis cases in Saudi Arabia between 2015-2019.

Parameters	Total (N=15662)	2015 (n=3345)	2016 (n=2993)	2017 (n=2962)	2018 (n=3359)	2019 (n=3003)	P-values^{^*}
Age, mean±SD^{^†}	40.12±17.58	41.43±17.15	40.70±17.38	39.92±17.41	39.68±18.12	38.77±17.70	<0.001
Gender
Male	10881 (69.5)	2309 (69.0)	2007 (67.1)	2049 (69.2)	2363 (70.3)	2153 (71.7)	0.002
Female	4781 (30.5)	1036 (31.0)	986 (32.9)	913 (30.8)	996 (29.7)	850 (28.3)	0.002
Nationality
Saudi	7765 (49.6)	1524 (45.6)	1447 (48.3)	1456 (49.2)	1708 (50.8)	1630 (54.3)	<0.001
Non-Saudi	7897 (50.4)	1821 (54.4)	1546 (51.7)	1506 (50.8)	1651 (49.2)	1373 (45.7)	<0.001

Values are presented as numbers and precentages (%).

SD: standard deviation

↵^† Post hoc analysis (Tukey’s HSD test): pairwise significant differences are 2015 vs. 2017 (p=0.005), 2015 vs. 2017 (p<0.001), 2015 vs. 2018 (p<0.001), 2015 vs. 2019 (p<0.001), and 2016 vs. 2019 (p<0.001).
↵^* Statistically significant difference between the years (p<0.05). OneWay ANOVA test was used for age and Chi-square test was used for gender and nationality.

Table 5

- Yearly trends of epidemiological characteristics of incident tuberculosis cases in Saudi Arabia between 2015-2019.

Parameters	Total (N=15662)	2015 (n=3345)	2016 (n=2993)	2017 (n=2962)	2018 (n=3359)	2019 (n=3003)	P-values
TB type
Pulmonary	11465 (73.2)	2456 (73.4)	2172 (72.6)	2146 (72.5)	2489 (74.1)	2202 (73.3)
Extrapulmonary	3868 (24.7)	817 (24.4)	756 (25.3)	752 (25.4)	799 (23.8)	744 (24.8)
Both	329 (2.1)	72 (2.2)	65 (2.2)	64 (2.2)	71 (2.1)	57 (1.9)	0.880
AIDS	234 (2.4)	47 (2.1)	35 (1.9)	37 (2.2)	48 (2.4)	67 (3.6)	0.005^{^*}
HIV status
Non-documented	4862 (31.0)	894 (26.7)	668 (22.3)	996 (33.6)	1315 (39.1)	989 (32.9)
Pending	1218 (7.8)	202 (6.0)	110 (3.7)	354 (12.0)	462 (13.8)	90 (3.0)
Unknown	3644 (23.3)	692 (20.7)	558 (18.6)	642 (21.7)	853 (25.4)	899 (29.9)
Documented	2451 (69.0)	2451 (73.3)	2325 (77.7)	1966 (66.4)	2044 (60.9)	2014 (67.1)
Negative^{^†}	10452 (96.8)	2365 (96.5)	2266 (97.5)	1904 (96.8)	1973 (96.5)	1944 (96.5)
Positive^{^†}	348 (3.2)	86 (3.5)	59 (2.5)	62 (3.2)	71 (3.5)	70 (3.5)	0.287^{^†}
Patient’s type
New	14544 (92.9)	3094 (92.5)	2746 (91.7)	2747 (92.7)	3127 (93.1)	2830 (94.2)
Failure	97 (0.6)	24 (0.7)	21(0.7)	19 (0.6)	20 (0.6)	13 (0.4)
Relapse	595 (3.8)	124 (3.7)	139 (4.6)	120 (4.1)	121 (3.6)	91 (3.0)
Post failure	291 (1.9)	73 (2.2)	65 (2.2)	45 (1.5)	59 (1.8)	49 (1.6)
Other	135 (0.9)	30 (0.9)	22 (0.7)	31 (1.0)	32 (1.0)	20 (0.7)	0.076
*Medication*
First line	14600 (97.3)	3104 (97.2)	2779 (96.6)	2841 (97.0)	3206 (97.8)	2670 (98.1)
Second line	398 (2.7)	88 (2.8)	98 (3.4)	87 (3.0)	72 (2.2)	53 (1.9)	0.004^{^{^*}}

Values are presented as numbers and precentages (%).

TB: Tuberculosis, AIDS: acquired immunodeficiency syndrome, HIV: human immunodeficiency virus

↵^† Percentages and statistical significance were calculated on patients with documented HIV serology.
↵^* Statistically significant difference between the years (p<0.05). Chi-square test was used.

Table 6

- Resistance to first-line antituberculosis drugs.

Drugs	2015	2016	2017	2018	2019	P-values
Isoniazid
Sensitive	89.5	87.2	91.3	90.5	93.6
Intermediate	3.2	2.6	1.5	1.6	1.3
Resistance	7.3	10.3	7.3	7.9	5.1	<0.001^{^*}
Pyrazinamide
Sensitive	90.7	88.8	90.5	93.4	91.1
Intermediate	3.4	2.6	2.2	2.1	2.3
Resistance	6.0	8.6	7.3	4.5	6.6	0.055
Ethambutol
Sensitive	94.1	93.5	96.1	96.5	97.2
Intermediate	3.1	2.8	1.5	1.7	1.2
Resistance	2.8	3.7	2.5	1.8	1.6	0.002^{^*}
Rifampicin
Sensitive	94.1	92.4	93.9	93.8	96.2
Intermediate	1.8	2.1	1.4	1.5	1.2
Resistance	4.0	5.5	4.7	4.7	2.6	0.067
Streptomycin
Sensitive	86.9	83.5	90.9	91.3	92.8
Intermediate	3.3	2.9	1.6	1.7	1.5
Resistance	9.8	13.6	7.5	6.9	5.7	<0.001^{^*}
Overall resistance patterns
Drug-susceptible	88.1	85.8	89.6	89.7	92.7	<0.001^{^*}
Monoresistance^{^‡}	13.6	17.0	12.5	10.6	13.2	0.001^{^*}
PDR	4.7	5.7	4.0	2.2	1.9	<0.001^{^*}
MDR	4.4	5.7	4.0	4.4	2.4	0.008^{^*}
XDR^{^§}	-	-	-	-	-

Values are presented as precentages (%).

PDR: polydrug resistance, MDR: multidrug resistance, XDR: extensive drug resistance

↵^* Statistically significant difference between the years (p<0.05) and Chi-square test was used.
↵^§ Data regarding second-line injectable drugs (capreomycin, kanamycin, and amikacin) were not available to establish XDR.
↵^‡ The calculation of monoresistance is not accurate, because all drugs were not tested for all the included patients; hence, the absence of result was assumed to be absence of resistance.