Diabetes mellitus remains a global public health problem. According to the International Diabetes Federation (IDF), the number of people with diabetes aged 20 to 79 years was 537 million in 2021 with a projected growth of 11.3% by 2030 [1] . Type 2 diabetes (T2D) accounts for about 90% of diabetes, with higher prevalence in low- and middle-income countries (LMICs) [1] . It is a progressive pathology fraught with macrovascular and microvascular complications. Macrovascular complications include stroke, myocardial infarction (MI) and diabetic arterial foot disease, arrhythmias, sudden death [2] . The pathophysiological mechanism is the process of atherosclerosis, which combines chronic inflammation of the arterial walls, oxidation of Low Density Lipoprotein (LDL) particles, oxidative stress, and atherosclerotic plaque formation [3] . Abnormalities in endothelial and vascular smooth muscle cell function, as well as a propensity to thrombosis, contribute to atherosclerosis and its complications [4] . The metabolic abnormalities that characterize diabetes, such as hyperglycemia, increased free fatty acids, and insulin resistance, each provoke molecular mechanisms that contribute to vascular dysfunction. These include decreased bioavailability of nitric oxide (NO), increased oxidative stress, disturbances of intracellular signal transduction, and activation of receptors for advanced glycation end products AGEs [4] . In addition, platelet function is abnormal, and there is increased production of several prothrombotic factors. Several studies have reported the prevalence of macrovascular complications in patients with type 2 diabetes. In Africa, Mbanya et al. in a 2003 meta-analysis found 5% - 8% of coronary heart disease, and 1.5% - 7% of lower limb amputations [5] . In Cameroon, Tamba et al. found 5% stroke, 17.1% arterial foot and 23.6% coronary heart disease [6] . These complications remain the most frequent causes of morbidity and mortality in patients with type 2 diabetes [7] [8] . The insidious, low-symptoms evolution of type 2 diabetes and its late diagnosis in Africa increase the risk of uncovering type 2 diabetes during a macrovascular complication with dire consequences in LMICs. These consequences include increased management costs, greater psychological impact on patients and their families, increased risk of morbidity and mortality and reduced life expectancy for patients [9] . The need of data on newly T2D diagnosed people and to tailor diabetes policies motivated us to conduct this study, the aim of which was to determine the prevalence and correlates of macrovascular complications at the time of diagnosis of type 2 diabetes.

The study was proposed to 350 patients with newly discovered type 2 diabetes. In all, 20 potential participants refused to sign the consent form and 44 were unable to undergo further investigations. We thus retained 286 patients (Figure 1).

Our study investigated the prevalence and correlates of macrovascular complications at type 2 diabetes diagnosis in an adult population. We included 286

BMI: Body Mass Index, HbA1c: Glycated hemoglobin, OR: Odd ratio. Logistic regression was adjusted with the sex variable.

patients seen in the internal medicine department (inpatient and outpatient) of Essos Hospital Center in Yaoundé. Our main findings were a prevalence of 17.5%, with 8.4% of stroke, 5.6% of myocardial infarction, and 3.4% of arterial foot ulcer. Correlates were hypertension, smoking, age ≥ 50 years old, glycated hemoglobin and obesity.

Our study population was predominantly male, with a mean age of 52 ± 12.3 years, which is in line with reports from the literature [11] [19] [20] . This was a relatively young population in full professional activity. Diabetes was discovered in 38.1% of patients fortuitously (systematic company-required health and wellness programs, routine check-up), which means that prevention policies need to be stepped up by raising awareness among the population in our context, who do not think about screening for chronic pathologies. In addition, type 2 diabetes was discovered concomitantly with a macrovascular complication in 17.5% of patients. This represents a heavy psychological and socio-economic burden for patients and their families, increasing the cost of managing the disease and reducing the validity of patients, which can lead to job loss in our context. A sedentary lifestyle was found in 57.7% of our patients, probably due to their professional status. Our patients were mostly employed in the private sector (38.5%), which may lead to restrictive working hours limiting the effectiveness of regular physical activity. This finding suggests that physical activity should be promoted in the workplace. Over and above the recognized metabolic effects of physical activity, when practiced in the workplace it improves professional performance and social relations [21] . Unrecognized hypertension was found in 15.7% of patients, and 31.5% had hypertension prior to the diagnosis of diabetes. Sosale et al. in India found a 23% prevalence of patients with hypertension in their study population [12] . The coexistence of diabetes and hypertension is associated with a six-fold increased risk of cardiovascular events compared with healthy individuals, and an increased risk of cardiovascular events and death from all causes [22] . The prevalence of macrovascular complications in our study was 17.5%. In the literature, the prevalence of macrovascular complications varies from study to study. Uddin et al. in Pakistan and Bonora et al. in Italy found 9%, while Morkos et al. in the USA, Gedebjerg et al. in Denmark, and Taneja et al. in India found 13%, 17% and 19.05%, respectively. These differing results may be attributed to sample sizes and patient recruitment methods in the different studies. Macrovascular complications were dominated in our study by stroke and MI. This has a negative impact in developing countries, especially as cardiovascular disease is the leading cause of disability and mortality among people living with diabetes worldwide [23] .

Studies show a 4.4-fold higher mortality rate among diabetics compared with non-diabetics, and reduced life expectancy after myocardial infarction [24] . The long pre-diabetic period and the presence of risk factors could explain the high prevalence of cardiovascular complications as soon as type 2 diabetes is diagnosed. The precarious socio-economic context, late diagnosis of diabetic disease, and ignorance of the population increase the risk of complications at the time of diagnosis of type 2 diabetes. Early detection, awareness of cardiovascular risk factors and optimal initial management of patients could reduce the risk of these complications. The correlates of macrovascular complications were hypertension, age ≥ 50 years old smoking, high glycated hemoglobin and obesity. These are the same factors found in the literature [25] [26] . Our study highlighted the heavy burden of type 2 diabetes associated with a complication in our context, and the importance of early diagnosis and control of cardiovascular risk factors.

This was a monocentric study, with recruitment methods particularly limited for the diagnosis of myocardial infarction. We didn’t have access to specific screening techniques such as myocardial scintigraphy or the systematic performance of stress tests on all patients, which would have had an impact on our sample.

Macrovascular complications are frequent at type 2 diabetes diagnosis and are represented by stroke and myocardial infarction in our study. This exacerbates the long-term psychological and socio-economic impact of type 2 diabetes, underscoring the need to intensify prevention policies. A multicenter study could be conducted to generalize our results.

· Macrovascular complications are frequent in our context at the time of diagnosis of type 2 diabetes

· Stroke and myocardial infarction are the main macrovascular complications at diagnosis of type 2 diabetes.

· Type 2 diabetes remains an incidental finding in the general population

· Correlates of macrovascular complications are hypertension, age ≥ 50 years old, smoking, high glycated hemoglobin and obesity.

· Need to increase awareness and screening policies for type 2 diabetes and cardiovascular risk factors.

We would like to thank all participants and their families who agreed to take part in this study.

Francine Mendane Ekobena, Martine Claude Etoa Etoga and Mesmin Dehayem drafted the study protocol and manuscript. Carole Laurence Ngo Yon supervised the cardiological analyses, Pauline Ngo Balôgôg conducted the biological analyses. Guy Dieudonné Mvogo conducted the statistical analyses. André Pascal Kengne, Eugene Sobngwi and Jean Claude Mbanya supervised the study. All authors read and approved the manuscript.

The authors declare no conflicts of interest regarding the publication of this paper.

Ekobena, F.M., Etoga, M.C.E., Dehayem, M., Yon, C.L.N., Balôgôg, P.N., Mvogo, G.D., Kengne, A.P., Sobngwi, E. and Mbanya, J.C. (2023) Prevalence and Correlates of Macrovascular Complications at Type 2 Diabetes Diagnosis in a Tertiary Hospital in Yaoundé, Cameroon. Journal of Diabetes Mellitus, 13, 269-283. https://doi.org/10.4236/jdm.2023.134021

Number: |___| Age: |___| Sex: Male |___| Female |___| Date: ……/…../20…

Marital status: Married |___| Single |___| Widower |__| Cohabiting couple |__|

Profession: Without|___| Public sector |___| Private sector |__| Student |__| Retired |__|

School level: None |___| Primary |___| Secondary |___| University |___|

Circumstances of discovery: fortuitously|___| Cardinal syndrome |___| Infection|___| Complications|___|

If complication (To specify): Ischemic stroke |___| Hemorrhagic stroke |___| myocardial infarction|___| Arterial Foot Ulcer |___|

Others Circumstances of discovery………………………………………………….……….……….……….

Newly High Blood pressure |___| Previous High Blood pressure |___|

Overweight |___| Obesity|___|

Family history of type 2 diabetes |___| Sedentary Lifestyle |___|

Tobacco |___| Hyperuricemia |___|

Dyslipidemia |___| If dyslipidemia (To specify): Hypo HDL|___| Hyper TG |___| Hyper LDL|___|

Glycaemia: |____| g/l Height |____| cm

Weight |____| kg Body mass index |____| kg/m²

abdominal circumference |____| cm Oxygen saturation |____|%

Blood pressure |____|mmHg Control blood pressure |____| mmHg after 15 minutes of rest

Cardiac frequency|____| Systolic pressure index |____|

Urine strips: glycosuria|___| Cetonuria |___| Leucocyturia |___| Nitrites|___| Albuminuria |___|

HA1c |____|%, Urea |___| g/l, Creatinemia |___| g/l,

SGPT |___| IU/l SGOT |___| IU/l

Uric acid |___| mg/l, Total Cholesterol |___| g/l, HDL cholesterol |___| g/l,

LDL cholesterol |___| g/l Triglyceridemia |___| g/l,

Troponin us |___| ng/l, CPKmb |___| IU/l

Brain scan: yes |___| No |___|, if yes, results…………………

Arterial Doppler Ultrasound of lower limbs: yes |___| No |___|, if yes, results…………………

Angio scan of lower limbs: yes |___| No |___|, if yes, results…………………

Electrocardiogram yes |___| No |___|, if yes, results…………………

Echocardiography: yes |___| No |___|, if yes, results…………………

Ischemic stroke: Yes |___| No |___|

Hemorrhagic stroke: Yes |___| No |___|

Arterial foot ulcer: Yes |___| No |___|

Myocardial Infarction: Yes |___| No |___|