The socio-demographic characteristics observed in this study had similarities with those of other studies. Of the 272 type 2 diabetes (T2D) patients in this study, about half (50.4%) were female, and the mean age of the patients was 56.34 ± 12.8 years. In line with these findings, the Middle East and Africa (MEA) cohort of the 3-year prospective DISCOVER study revealed that nearly half (47.5%) were females, and the mean age of patients was 54.3 ± 10.8 years [18]. Likewise, similar trends were seen in a study done in Tikur Anbessa Specialized Hospital (TASH), where the mean age of patients was 58 ± 11.2 years, albeit with a slight female predominance (57%) [19]. These demographic findings indicate that T2D mainly affects middle-aged individuals without a remarkable gender predilection.
There was a high prevalence of HTN (73.2%) among patients with T2D in this study, which was consistent with that of the study done at TASH, where HTN was seen in 69% of T2D patients [19]. However, the prevalence of HTN in the present study was much higher than that of the studies done in a tertiary hospital in northeast Ethiopia (43.3%) [20] and Jimma University Specialized Hospital (24.9%) [21], both of which included type 1 and type 2 diabetes. The higher proportion of HTN among T2D patients in the present study as compared to the latter studies might be due to differences in the patients’ characteristics, mainly the type of diabetes.
In this study, a significant proportion of T2D patients (48.5%) had poor glycemic control, and more than half (56.3%) were prescribed oral antidiabetic agents, whereas in the study from Dessie Town hospitals, most T2D patients (85.7%) had poor glycemic control, and the majority (66.6%) were prescribed oral antidiabetic agents [11]. Similarly, in a study from TASH, 69.1% of T2D patients had poor glycemic control, and the most commonly used antidiabetic treatment regimen was the combination of metformin and insulin, prescribed for 37.5% of the patients [19]. This underscores the need to optimize the types and dosages of antidiabetic agents, along with diabetes education on drug adherence, medical nutrition therapy, weight management, and exercise, to improve glycemic control and ultimately minimize the burden of vascular complications.
The overall prevalence of vascular complications (39%) among T2D patients in this study was lower than that of the study done in 10 general hospitals in the Tigray region (54%) [9], but it was higher than the finding reported from the studies done in Felege Hiwot Hospital (23.3%) [10], and University of Gondar Referral Hospital (28%) [22]. The prevalence of vascular complications in the study area might have been higher than the reported figure if meticulous evaluations and appropriate diagnostic modalities were used.
The prevalence of microvascular complications (23.5%) in the present study was lower than that of the studies done in other countries, including the USA (77%) [23], Brazil (41.6%) [24], China (57.5%) [25], India (48%) [26], Ghana (35.3%) [27], and Nigeria (50%) [28]. It was also lower than the findings of local studies including Dessie Town hospitals (37.9%) [11], Gurage Zone (61%) [29], and Jimma University Hospital (41.5%) [30], though it was higher than that of the study done at the University of Gondar Hospital (20.4%) [31]. The commonest microvascular complication in the present study was neuropathy (11.8%) followed by nephropathy (9.2%) and retinopathy (8.1%); this pattern was consistent with that of the studies from India and Nigeria, where neuropathy was seen in 37% and 69.6% of the patients, followed by nephropathy seen in 20% and 54.5%, and retinopathy seen in 17% and 48.9% of the patients, respectively [26, 28]. The wide variations in the prevalence of vascular complications of T2D among these studies may be explained by the heterogeneity of the patient characteristics and differences in the screening methods used to diagnose the complications.
The prevalence of macrovascular complications of T2D in this study was 21%, which was higher than the findings of the studies done in Saudi Arabia (12.1%) [13], Sri Lanka (13.7%) [14], but lower than the findings done in South India (29.7%) [32], Yemen (25.4%) [33], and South Africa (56%) [34]. CAD (12.1%) was the leading macrovascular complication in the present study, consistent with the other studies from Sri Lanka (10.6%) [14], South India (15.1%) [32], and Yemen (17.8%) [33]. However, CAD was the least common macrovascular complication in a study from Tigray, Ethiopia (3%) and TASH, Ethiopia (< 2.5%) [35]. The present study found that peripheral artery disease (4.4%) was the least common macrovascular complication; however, it was the commonest macrovascular complication according to studies done in South India (15.1%) [32], Tigray, Ethiopia (9%) [9], and TASH, Ethiopia (5.8%) [35]. The lowest percentage of PAD among the macrovascular complications in the present study may be explained by the unavailability of Doppler arterial ultrasound service in the hospital, contributing to a lower rate of screening and diagnosis of PAD.
The present study revealed that age ≥ 60 years, diabetes duration of > 5 years, and HbA1c value ≥ 7% were significantly associated with microvascular complications, and this was consistent with the findings of the studies done in Dessie Town hospitals [11], Sri Lanka [14], Ethiopia, and a tertiary health care hospital in India [26]. Likewise, poor glycemic control and longer duration of diabetes in a study from Saudi Arabia [13] and increasing age and duration of diabetes in a study from Nigeria [29] were strongly associated with the development of microvascular complications. Unlike the other studies [11, 29], hypertension and dyslipidemia were not associated with microvascular complications in the present study. Therefore, T2D patients with older age, prolonged duration of diabetes, and/or poor glycemic control require close monitoring for the prevention and early detection of microvascular complications.
Diabetes duration of 5–10 years was significantly associated with the development of macrovascular complications in the present study, which was consistent with the studies from Saudi Arabia [13] and Yemen [33]. Unlike the present study, poor glycemic control was associated with a higher prevalence of macrovascular complications in a study from Saudi Arabia [13], and age was strongly associated with the overall prevalence of macrovascular complications in studies from Yemen [33] and Sri Lanka [14]. The present study highlights the importance of diabetes duration, more than glycemic control, as a determining factor for the development of macrovascular complications. Hence, a very low threshold is required to screen T2D patients for macrovascular complications starting from the time of diagnosis of T2D, particularly for those with prolonged diabetes duration.
There are certain limitations to this study. First, as the study was obtained from medical records, the accuracy of the recording of the patients’ data may affect the reliability of the findings of the study. Second, the unavailability of standardized screening methods for some of the vascular complications might have caused an underestimation or overestimation of their prevalence. Finally, because of the cross-sectional nature of the study, a definite causal relationship between the determining factors and the vascular complications of type 2 diabetes cannot be established.