Diabetic foot ulcer (DFU) is one of the most common major severe and debilitating chronic complications of diabetes mellitus (DM) and consists of lesions in the deep foot tissues associated with neurological disorders like peripheral neuropathy (PN) and peripheral vascular disease (PVD) [1][2]. It is a highly morbid consequence of long standing and poorly managed diabetes and it is one of the most common causes of hospital admissions. Over the years, its prevalence is increasing exponentially across the globe following the persistent increment of DM worldwide. It is estimated that, every thirty seconds, a lower limb or part of it is lost to amputation as a consequence of diabetes globally [1][3]. A meta-analysis study showed about 30 million people affected with DFU globally with a prevalence of 6.3% [3][4]. In Africa the prevalence ranges from 3.2% - 19.1%, in Cameroon 9.9% and South-West region (SWR) being 11.8% [4]-[6]. DFU is characterized by poor short- and long-term survival especially when associated with other comorbidities. Mortality in hospitalized diabetic patients with DFU is quite considerable compared to those without. Mortality due to DFU was reported to be 14% in Africa and 40.5% in a cohort of Nigerians [7]-[9]. This problem though well-known still poses a huge burden in low-income countries like Cameroon. Several studies have been carried out in Cameroon on DFU but there is paucity of data concerning the intra-hospital outcome following treatment. Hence, it is important to identify contributing factors which will predict outcome in this group of patients, thus enabling optimized management strategy and stem this tide of high DFU related mortality.

A multi-centered retrospective and analytic study was carried out on patients admitted in the Limbe Regional Hospital (LRH), Buea Regional Hospital Annex (BRHA) & the Kumba Regional Hospital Annex (KRHA) from January 2019 to December 2023. These hospitals are the major referral hospitals in the South-West Region (SWR) of Cameroon and have a high influx of patients from other parts of the region. They have specialists, trained doctors and other fully experienced staff who help in patient diagnosis and management. They all have major units including a Diabetic unit headed by a Diabetologist and a surgical department having over 25 beds each. Our study involved all files of patients admitted within the study period.

After obtaining ethical clearance from the Institutional Review Board of the Faculty of Health Sciences, University of Buea (IRB FHS-UB) and administrative authorization from the Regional Delegate of Public Health (RDPH) and administrative boards of LRH, BRHA & KRHA, the ward charges of the surgical departments of these health facilities were also informed about the study and permission given to have access to patient’s records.

Patient files were obtained from the archives of the LRH, BRHA and KRHA on scheduled days. Diabetic foot problems were confirmed by one of the following physician’s handwritten diagnoses as: “diabetic foot”, “diabetic foot ulcers”, “diabetic foot infections”, “diabetic foot gangrene” or a wound below the ankle in a patient diagnosed with diabetes placed under the Wagner’s classification or grading system or described as superficial or deep foot infections. The data from the files were retrieved using a well-structured data collection form. We excluded files with incomplete objective data (diagnosis and precised treatment not mentioned) and files of patients who were discharged against medical advice (DAMA) and those who might have been readmitted for the same problem during the study period. A simple consecutive sampling method was used. Data was obtained on the following variables:

Socio demographic: Age, gender, occupation, religion, time of diagnosis, those on treatment or not.

Comorbidities & past history: Hypertension (HTN), HIV, Nephropathy, family history of diabetes, duration of diabetes, history of ulceration, history of surgical approach (debridement, amputation), alcohol intake, smoking.

Clinical patterns: Based on the depth of the wound and the severity, the Wagner’s system of classification (Grade I to V) was used and the topography was described by the anatomical location of the ulcer (forefoot, midfoot and hindfoot) and the extent as described by the treating physician.

Treatment modalities: conservative (Insulinotherapy, Analgesics, antibiotherapy, bedside wound care) or Surgical (surgical debridement, minor or major limb amputation).

Treatment outcome: The treatment outcome was described by the presence of complications or not and in terms of survival (dead or alive).

A total of 6,760 hospital records of patients admitted at the surgical units of Limbe, Buea and Kumba Regional Hospitals over a five-year period (January 2019 to December 2023) were reviewed, of which 394 cases were admitted for DFU, giving a proportion of 5.8%. Thirty-four files were excluded, with 21 being discharged against medical advice (DAMA) and 13 with incomplete objective data, giving a definitive retained sample size of 360.

Of the 360 files retained 195 (54.2%) were males and 165 (45.8%) were females giving a sex ratio of 1.2:1. The ages ranged from 16 to 100 years with a mean age of 55.92 ± 15.19 years. Most represented age range was 41 - 60 years (49.2%) with majority being farmers (40.3%).

Fifty-four (15%) of them were diagnosed of diabetes on admission and 306 (85%) were aware of their diagnosis with a median duration of diagnosis of 60 (24 - 108) months. Hypertension was the most common comorbidity (49.3%), followed by HIV (16.7%) and kidney disease (9.3%) (Table 1).

Table 1. Socio-demographic characteristics of the retained files, N = 360.

With regards to the clinical patterns according to the Wagner system of classification, 172 presented with Wagner IV (47.8%) followed by Wagner V (24.2%) and anatomically the majority presented with ulcers at the forefoot (46.9%), followed by that on the hindfoot (30%) (Table 2).

Table 2. Clinical characteristics of diabetic foot ulcers.

Amongst the 360 patients, over 175 patients were managed surgically with major lower limb amputation (48.7%). 90 (51.4%) of patients had above knee amputations (AKA) and 62 patients (35.4%) had below knee amputations (BKA) (Figure 1). The rest were either managed by repeated surgical debridement (32.3%), bedside debridement (7%) or regular wound care (12%).

Figure 1. Level of lower limb amputation.

Over 19% of patients (n = 71) had complications following treatment with majority having surgical site infections and pressure ulcers (Figure 2).

132 (36.7%) of patients were hospitalized for >16 days with a median duration being 14 days. Seventy-three patients (20.3%) died during hospitalization while the rest of the patients were discharged after achieving satisfactory wound healing and clinical recovery (79.7%) (Figure 3).

On bivariate logistic regression analysis, factors such as age > 60 years, presence of hypertension (p = 0.013), renal disease (p = 0.002), Wagner grade > 3 (p < 0.001), and the development of SSI (p = 0.001), were significantly associated with high mortality. However, on multivariate analysis the factors that were independently associated with higher in-hospital mortality were Hypertension and the Development of SSI (aOR 2.680, p < 0.017 and aOR 12.562, p < 0.001 respectively) (Table 3).

Figure 2. Complications following treatment.

Figure 3. Survival outcome of diabetic foot ulcer.

Table 3. Multivariate analysis for independent associated factors for higher in-hospital mortality in patients with DFU.

In this study we had a mean age of 55.92 ± 15.19 years, similar to findings from other studies done by Pemayun et al. in Indonesia, Shabbay et al. in Tanzania and Tamfu et al. in Cameroon [9]-[11].

Males were more affected than females [9][12]-[14]. This correlates with the reported high prevalence of diabetes mellitus in males than females coupled with the fact that males are more likely involved in risky behaviors (excessive alcohol consumption, smoking, poor diet and non-compliance to diabetic foot guidelines) which predispose them to injury, including the feet, and eventually foot disease.

This is in contrast with another studies done by Kim et al. in Korea and Pemayun et al. in Indonesia which showed no gender variations as females were as much affected as males [9][12]. The median duration of diabetes was 60 (24 - 108) months. Majority (53%) had the disease for more than five years and 15% of the patients were newly diagnosed with diabetes mellitus at presentation which was similar to the 13.1% by Edo et al. in Nigeria and much higher than the 8% gotten by Mutonga et al. in Kenya [13][14].

DFU is a common chronic complication in hospitalized patients with diabetes mellitus. Its most common clinical patterns according to the Wagner Meggitt’s classification system are grades IV and V, anatomically located at the forefoot. Major lower extremity amputations are the most frequent treatment modality. However, mortality remains high following treatment aggravated principally by the presence of comorbidities like hypertension and the development of surgical site infection. Hence, there is a need for comprehensive care models with trained multidisciplinary teams to increase the effectiveness in the treatment of DFUs. With early detection of diabetes mellitus, identification of comorbidities like hypertension; timely interventions and effective wound care, the burden of diabetes mellitus will be greatly mitigated, alongside its attendant complications such as diabetic foot ulcers.

The retrospective nature of data collection meant valuable information could have been left out during recruitment. Also possible physician hand written diagnoses or misclassification and the exclusion of incompletely filled-in files and those discharged against medical advice, constitute a major setback in the generalization of our findings. Also, we did not consider the glycemia control values, presence of peripheral arterial disease and results of microbiology analysis.

We acknowledge the administration and staff of all our 3 study sites.