The Prevalence and Risk Factors of Bronchiectasis among Adults Based on CT Scan Findings: A Retrospective Single-Center Study ()
1. Introduction
Bronchiectasis is a long-term lung condition that causes the airways to widen. This condition can result in a mucus-producing cough and frequent lung infections [1] [2]. Breathing problems, a decline in lung function, a worsening quality of life, and an increased risk of early death are often associated with this lung disease [3] [4]. Bronchiectasis has a significant impact on both healthcare systems and society, with frequent hospitalizations and deaths being the main contributors to this burden [5].
According to global data, bronchiectasis diagnoses have increased in recent years [6]. In Europe, between 2005 and 2011, the number of hospitalized patients for bronchiectasis in Germany increased by 2.9% annually. The United States has reported similar findings [7]. In the United States, the estimated prevalence of bronchiectasis among adult patients was 139 per 100,000 [8]. China has the highest prevalence of bronchiectasis, with over 1,200 per 100,000 people over 40 years old affected by the disease [2]. About 7.4% of people in Africa have post-TB bronchiectasis [9]. A large study of over 1,200 people with bronchiectasis found that the most common cause was unknown (idiopathic), accounting for 40% of cases. Following this were post-infective bronchiectasis (20%), chronic obstructive pulmonary disease (COPD) (15%), connective tissue disease (CTD) (10%), immunodeficiency (5.8%), and asthma (3.3%). In India, previous lung tuberculosis (pulmonary TB) was the leading cause of bronchiectasis [10].
This study aims to provide much-needed data on the prevalence and risk factors of this disease in this underserved population. This study’s findings will have significant implications for the prevention and treatment of bronchiectasis in Somalia. The identification of risk factors will help target interventions for high-risk populations. Additionally, the data on prevalence will help to advocate for increased resources for the diagnosis and management of bronchiectasis in Somalia.
2. Methods and Materials
2.1. Study Design
The Türkiye Training and Research Hospital in Mogadishu, Somalia, conducted this retrospective, single-center study.
2.2. Patient Selection
The study included all patients with high-resolution CT scan findings treated at the outpatient unit of Mogadishu Somalia Türkiye Training and Research Hospital between January 1, 2021, and December 31, 2022.
Patients with high-resolution CT scan findings were eligible for inclusion. Patients who did not have chest CT scans were excluded.
2.3. Data Collection
We collected data from the medical records of eligible patients. The following information was collected: We gathered data on demographic characteristics such as age and sex, smoking history, medical history such as pneumonia, tuberculosis, asthma, and other chronic lung diseases, clinical features, and HRCT results.
2.4. Data Analysis
We analyzed the data using SPSS software (version 26.0). We used descriptive statistics to characterize the study population. We used univariate and multivariate analyses to identify the risk factors associated with bronchiectasis.
2.5. Ethical Considerations
We obtained an approval letter from the review board of Mogadishu-Somali Türkiye Recep Tayyip Erdogan Training and Research Hospital (MSTH: 10621, Ref. No. 625). We followed the relevant guidelines of the Helsinki Declaration for all methods. We informed the participants about the study’s purpose and obtained their written informed consent.
3. Results
Among 301 patients, 139 (46.1%) received a diagnosis of bronchiectasis.
The mean age in the bronchiectasis group was 58.42 years (SD ± 18.94), while in the non-bronchiectasis group, it was 54.55 years (SD ± 20.58). The odds ratio (OR) for age, with a 95% confidence interval (CI), was 0.513 to 0.920, and the p-value was 0.092, indicating a non-significant difference. The age distribution showed a significant association, with 26.6% of patients aged 50 years or younger in the bronchiectasis group compared to 41.4% in the non-bronchiectasis group (OR = 0.514, 95% CI: 0.315 to 0.839, p = 0.007). For patients older than 50, the bronchiectasis group had 73.4%, while the non-bronchiectasis group had 58.6%. The gender distribution did not show a significant difference, with 49.6% of males in the bronchiectasis group and 53.7% in the non-bronchiectasis group (OR = 0.850, 95% CI: 0.540 to 1.338, p = 0.482) (Table 1).
Table 1. Baseline characteristics of patients with & without bronchiectasis.
Patient characteristic |
Bronchiectasis (n = 139) |
Non-bronchiectasis (n = 162) |
OR** (95% CI*) |
P-Value |
Age (years), mean ± SD |
58.42 ± 18.94 |
54.55 ± 20.58 |
(0.513 - 0.920) |
0.092 |
Age group |
≤50 Years |
37 (26.6%) |
67 (41.4%) |
0.514 (0.315 - 0.839) |
0.007 |
>50 Years |
102 (73.4%) |
95 (58.6%) |
Gender |
Male |
69 (49.6%) |
87 (53.7%) |
0.850 (0.540 - 1.338) |
0.482 |
Female |
70 (50.4%) |
75 (46.3%) |
Smoking status |
Yes |
25 (18.0%) |
29 (17.9%) |
1.006 (0.557 - 1.815) |
0.985 |
No |
114 (82.0%) |
133 (82.1%) |
Comorbidities |
DM*** |
10 (7.2%) |
13 (8.0%) |
1.104 (0.851 - 1.434) |
0.895 |
HTN**** |
17 (12.2%) |
22 (13.6%) |
DM/HTN |
5 (3.6%) |
8 (4.9%) |
No |
107 (77.0%) |
119 (73.5%) |
*CI (Confidence Interval), **OR (Odd Ratio), ***DM (Diabetes Mellitus), ****HTN (Hypertension).
The results highlight significant differences in CT scan findings and echocardiogram results. Cystic bronchiectasis is notably present in 56.8% of cases, compared to none in the non-bronchiectasis group (p-value = 0.000). Traction bronchiectasis is also significantly more prevalent in cases (43.2%) compared to non-bronchiectasis (0.0%). A higher percentage of people with emphysema, multiple tree-in-bud nodular infiltrates, fibrotic changes, ground glass, and septic pulmonary emboli show up on CT scans than people who don’t have these conditions. Echocardiogram findings show a higher percentage of normal results in controls (15.1%) compared to cases (10.5%), with a statistically significant p-value of 0.008. Other types of echocardiograms, like R-H DILATED/PHTN, PHTN, R-H DILATED, and EF 40-45, show different percentages between the two groups (Table 2).
Table 2. Comparison of laboratory parameters in patients with and without bronchiectasis.
Variables |
Bronchiectasis
(n = 139) |
Non-bronchiectasis
(n = 162) |
P-Value |
CT scan findings* |
|
|
|
Cystic bronchiectasis |
79 (56.8%) |
0 (0.0%) |
0.000 |
Traction bronchiectasis |
60 (43.2%) |
0 (0.0%) |
Consolidation |
0 (0.0%) |
30 (18.5%) |
Cavitary Lesion |
0 (0.0%) |
28 (17.3%) |
Lung metastasis |
0 (0.0%) |
20 (12.3%) |
Ground glass |
0 (0.0%) |
18 (11.1%) |
Fibrotic changes |
0 (0.0%) |
19 (11.7%) |
Filling defect segmental arteries |
0 (0.0%) |
12 (7.4%) |
Emphysema |
0 (0.0%) |
14 (8.6%) |
Multiple tree-in-bud nodular infiltrates |
0 (0.0%) |
10 (6.2%) |
Septic pulmonary emboli |
0 (0.0%) |
11 (6.8%) |
Echo findings |
|
|
Normal |
21 (15.1%) |
17 (10.5%) |
0.008 |
R-H DILATED /PHTN |
20 (14.4%) |
15 (9.3%) |
PHTN** |
24 (17.3%) |
27 (16.7%) |
R-H DILATED |
9 (6.5%) |
22 (13.6%) |
EF 40-45*** |
19 (13.7%) |
8 (4.9%) |
No Echo |
46 (33.1%) |
73 (45.1%) |
*CT (Computed Tomography), **PH or PHTN (Pulmonary Hypertension), ***EF (Ejection Fraction).
People who had bronchiectasis (case) had higher hemoglobin levels (12.31 ± 2.53 vs. 11.39 ± 2.80, p = 0.003) and lower C-reactive protein (CRP) levels (35.86 ± 39.74 vs. 50.66 ± 49.75, p = 0.005) than people who did not have bronchiectasis. (Table 3)
Table 3. Comparison of laboratory parameters in patients with and without bronchiectasis.
Laboratory parameters |
Bronchiectasis (n = 139) |
Non-bronchiectasis (n = 162) |
P-Value |
HGB |
12.31 ± 2.53 |
11.39 ± 2.80 |
0.003 |
PLT |
346.99 ± 142.62 |
323.75 ± 167.87 |
0.201 |
WBC |
9.05 ± 6.90 |
9.40 ± 8.81 |
0.705 |
Neutrophil |
7.26 ± 8.26 |
7.74 ± 9.39 |
0.642 |
Lymphocyte |
2.26 ± 2.55 |
2.22 ± 2.78 |
0.899 |
Monocyte |
1.29 ± 2.60 |
1.72 ± 3.23 |
0.208 |
Eosinophils |
1.45 ± 5.40 |
4.05 ± 16.71 |
0.080 |
Sedimentation |
33.32 ± 51.43 |
38.97 ± 57.08 |
0.371 |
CRP |
35.86 ± 39.74 |
50.66 ± 49.75 |
0.005 |
*HGB (Hemoglobin), **PLT (Platelet), ***WBC (White Blood Count), ****CRP (C-reactive protein).
The analysis of risk factors associated with bronchiectasis revealed significant findings. People with bronchiectasis were more likely to cough up mucus (91.4% vs. 78.4%, OR = 2.917, p = 0.002) and experienced less air entering their lungs during listening (25.9% vs. 39.5%, OR = 0.809, p = 0.046). The history of tuberculosis was significantly more common in bronchiectasis than non-bronchiectasis (66.2% vs. 37.7%, OR = 3.241, p = 0.000) (Table 4).
Table 4. Risk Factors Associated with and Without Bronchiectasis.
Risk factors |
Bronchiectasis (n = 139) |
Non-bronchiectasis (n = 162) |
OR* (95% CI)** |
P-Value |
Cough |
Productive |
127 (91.4%) |
127 (78.4%) |
2.917 (1.448 - 5.875) |
0.002 |
Dry |
12 (8.6%) |
35 (21.6%) |
Dyspnea |
Yes |
132 (95.0%) |
157 (96.9%) |
0.601 (0.186 - 1.936) |
0.285 |
No |
7 (5.0%) |
5 (3.1%) |
Hemoptysis |
Yes |
38 (27.3%) |
37 (22.8%) |
1.271 (0.753 - 2.145) |
0.368 |
No |
101 (72.7%) |
125 (77.2%) |
Recurrent fever |
Yes |
111 (79.9%) |
121 (74.7%) |
1.343 (0.779 - 2.317) |
0.288 |
No |
28 (20.1%) |
41 (25.3%) |
Lung
auscultation |
Decrease air entry |
36 (25.9%) |
64 (39.5%) |
0.809 (0.656 - 0.998) |
0.046 |
Crepitation |
13 (9.4%) |
7 (4.3%) |
Crackles |
68 (48.9%) |
70 (43.2%) |
Wheezing |
22 (15.8%) |
21 (13.0%) |
History of
tuberculosis |
Yes |
92 (66.2%) |
61 (37.7%) |
3.241 (2.018 - 5.205) |
0.000 |
No |
47 (33.8%) |
101 (62.3%) |
Asthma |
Yes |
11 (7.9%) |
18 (11.1%) |
0.688 (0.313 - 1.510) |
0.349 |
No |
128 (92.1%) |
144 (88.9%) |
COPD*** |
Yes |
7 (5.0%) |
10 (6.2%) |
0.806 (0.298 - 2.177) |
0.670 |
No |
132 (95.0%) |
152 (93.8%) |
**CI (Confidence Interval), *OR (Odd Ratio), ***COPD (Chronic obstructive pulmonary disease).
4. Discussion
This study addresses this critical public health problem by providing Somalia’s first comprehensive assessment of bronchiectasis. It also assessed various potential risk factors for bronchiectasis, including demographic characteristics and medical history. This comprehensive assessment provides valuable insights into the risk factors for bronchiectasis in Somalia.
The prevalence of bronchiectasis in Somalia is still unknown. However, based on our clinical observations and the prevalence of tuberculosis in Somalia, it remains high. Only 80.6% of tuberculosis (TB) patients in Benadir received a cure, according to research in Somalia. This is significantly lower than the World Health Organization’s (WHO) target of at least a 90% success rate for TB treatment. This shortfall may increase the risk of developing bronchiectasis [11].
A study in South Africa looked at 175 patients and tested them for HIV. More than a third (61, or 34.9%) were HIV-positive. Interestingly, a significant proportion (86.9%, or 53 patients) of these HIV-positive patients identified tuberculosis (TB) as the cause of their bronchiectasis (TB) identified as the reason behind their bronchiectasis [12].
In Somalia, although there is no population-based study about HIV prevalence, there is a study about the prevalence of HIV among HIV patients in Benadir, Somalia, which showed that the prevalence was very low, around 1.5% [13]. This study presents the first prevalence report on bronchiectasis in Somalia, estimating a rate of 46.1%, compared to estimates of 7.4% in Sudan and 4.9% in Ethiopia . At 67 per 100,000, Germany has a lower rate than the UK, where new cases reach 566 and 485 per 100,000 in women and men, respectively [14]. The most notable finding of this study was that of bronchiectasis, which is a factor that is comprised of comorbid pulmonary conditions such as a previous pulmonary TB history. In a similar study, alongside other severe infections, the high prevalence of tuberculosis in the Indian subcontinent made it the dominant underlying cause of bronchiectasis [15]. In contrast, in a study in Germany, most bronchiectasis patients had COPD [6]. Our study revealed a high prevalence of bronchitis among individuals older than 50 years. Similar to our research, one study revealed the prevalence of bronchiectasis in individuals exceeding 75 years of age in Italy [16]. The reason that our subjects are younger than the Italian group may be related to the high pulmonary TB in younger adults.
Our findings regarding the relationship between asthma and COPD did not reach statistical significance, unlike the results reported in another study. Among bronchiectasis patients, 36% had COPD, and a significant portion (43%) had asthma diagnoses.
The reason for the lack of relationship between asthma/copd and bronchiectasis may relate to the high prevalence of post-TB bronchiectasis and the low prevalence of COPD in our country due to low smoking habits in the population. This suggests a high prevalence of these co-existing conditions [17]. Productive cough was a common symptom among our patients, similar to another study from Australia, which showed chronic cough was the most common symptom [18].
Overall, the goal of this study is to fill in a major knowledge gap about the prevalence and risk factors of bronchiectasis in low-income countries where infectious diseases like tuberculosis are common. This could lead to better clinical outcomes and a lower disease burden in this high-risk population. The reason for the high sedimentation rate may be related to the infectious process at the time of presentation, although it was not specific for bronchiectasis.
5. Limitations
This study has some limitations. Firstly, the accuracy and completeness of the data recorded in the medical records limit a retrospective design. Secondly, a single hospital in Somalia conducted the study. This limits the findings’ generalizability to the entire Somali population. Third, the study had a relatively small sample size, which may limit its statistical power. Fourth, some of the data in the study, such as smoking history, was self-reported. This type of data is subject to recall bias, which can limit the accuracy of the findings. Finally, the absence of information on treatment strategies and management outcomes for bronchiectasis was also a limitation of our study.
6. Conclusion
In conclusion, the study found that bronchiectasis is a common disease in Somalia, with an estimated prevalence of 46.1%. The study also identified a number of risk factors for bronchiectasis, including a history of tuberculosis. This study’s findings have important implications for the prevention and treatment of bronchiectasis in Somalia. Public health interventions aimed at improving access to tuberculosis prevention and treatment strategies could help reduce the burden of bronchiectasis in this population. Future research can use the findings of this study to develop targeted prevention and treatment strategies for this disease.
Acknowledgements
We would like to express our sincere gratitude to Dr. Ahmed Muhammad Bashir for his invaluable guidance and support throughout the research process leading to this article.