Introduction: The aim of this study was to determine the prevalence and risk factors of diabetes mellitus in the adult population of Porto-Novo. Methods: A cross-sectional study with random sampling, stratified cluster, was used. Fasting blood glucose was measured in capillary blood (Accu-Chek Active). Diabetes mellitus was defined as fasting glucose ≥ 1.26 g/L, and fasting hyperglycemia in non-diabetic fasting glucose ≥ 1.10 and < 1.26 g/L. Results: The survey involved 240 individuals. The sex ratio was 0.48. The mean age was 46 ± 13 years (range 25 - 80 years). The prevalence of hyperglycemic patients was 7.9%. The prevalence of diabetes was 6.7%, including 3.3% of unknown diabetes, half of diabetics. The prevalence of fasting hyperglycemia without diabetes was 1.2%. The risk factors for diabetes type 2 onset were a family history of diabetes (p = 0.017), older age (p = 0.003), hypertension (p = 0.005) and abdominal obesity (NCEP: p = 0.044; FID: p = 0.001). Conclusion: These high figures confirm the increasing prevalence of diabetes mellitus in Benin, documented in many developing countries.
Diabetes mellitus is one of the most common and worldwide non-communicable diseases [
The World Health Organization (WHO) estimated in 1995 that the prevalence of diabetes mellitus was about 135 million of adults worldwide [
In Benin, several prevalence surveys were conducted in the past. Thus, the frequency of diabetes mellitus was:
• 1.1% in 2001 [
• 3.3% in Cotonou in 2002 [
• 0.9% in Oueme Department in 2007 [
Since 2007, to our knowledge, there have been no reports of diabetes mellitus prevalence in Porto-Novo, capital of the Republic of Benin. The present work was therefore designed to determine the prevalence and risk factors of diabetes mellitus type 2 in the urban adult population of Porto-Novo.
The study was cross-sectional, descriptive and analytical, and was conducted according to the “STEP wise” approach recommended by WHO for the screening and monitoring of risk factors of non-communicable diseases [
Fasting hyperglycemia without diabetes (HJND) was defined with any person not known as diabetes based on fasting glucose and > or = 1.10 and < 1.26 g/L. The collected data were analyzed with the EPI INFO version 3.5.3 software. For comparisons between data, a value of p < 0.05 was considered statistically significant.
The minimum number of participants to include, calculated by the Schwartz formula, was 211. This figure was increased by 10% to account for non-responders, resulting in a sampling size of 232 subjects, rounded 240 subjects included in the study.
The mean age of patients was 46.07 ± 12.63 years, with a range from 25 to 80 years. The age group 35 - 45 was the most represented. Women were the majority (162 against 78 men), respectively 67.5% against 32.5% (sex ratio 0.48).
The overall prevalence of hyperglycemia (diabetes mellitus and HJND) was 7.9%; that of 1.2% HJND; and that diabetes mellitus was 6.7%. Of the 16 patients with diabetes mellitus, 8 new cases were detected by the survey, representing 50% of all cases of diabetes mellitus, corresponding to a prevalence of unrecognized diabetes of 3.3% (
The prevalence of diabetes mellitus was 6.4% for men against 6.8% in women (p = 0.91), suggesting that the sex
Fasting glucose | Number | Percentage |
---|---|---|
Normal | 221 | 92.1 |
Non-diabeticfasting hyperglycaemia | 3 | 1.2 |
Diabetes mellitus | 16 | 6.7 |
Total | 240 | 100 |
Diabetes prevalence (%) | p | |
---|---|---|
Sex M F | 6.4 6.8 | 0.912 |
Age [25 - 35] [35 - 45] [45 - 55] [55 - 65] ≥65 | 0.0 5.7 3.7 12.8 21.7 | 0.003 |
HBP yes No | 11.3 2.4 | 0.005 |
Abdominal obesity FID NCEP | Yes 10.8 No 0.0 Yes 10.3 No 3.8 | 0.001 0.044 |
Family history of diabetes yes No | 14.0 4.7 | 0.017 |
was not associated with an increased prevalence of diabetes (
The prevalence of diabetes increased with age of the subjects studied, with a peak of 21.7% among those aged ³65 years (p = 0.003%).
The prevalence of diabetes mellitus in hypertensive patients was 11.3% against 2.4% among non-hypertensive, with a statistically significant difference (p = 0.005).
The prevalence of diabetes mellitus in subjects with abdominal obesity according to IDF criteria was 10.8% against 0.0% in patients with no abdominal obesity (p = 0.001). According to the criteria of the National Cholesterol Education Program (NCEP), it was 10.3% in obese, against 3.8% in non-obese (p = 0.044)
The prevalence of diabetes mellitus in patients with a family history of diabetes mellitus (1 generational distance) was 14.0%, against 4.7% in patients with no family history of diabetes mellitus (p = 0.017).
The mean age of the study populations differed significantly between the prevalence studies available. Thus, the average age of patients in our study was 46.07 years, relatively close to those reported by Djrolo et al. (39.4 years in Cotonou (Benin) in 2007) [
Age over 40 years is an occurrence known risk factor for type 2 diabetes [
In our survey, female was predominantly represented 67.5% of the sampled subjects and a sex ratio of 0.48. This reflects the female population in Benin.
The prevalence of HJND was 1.2% in our study population, similar to that reported for Ouémé (1.2%) in STEPS survey [
The prevalence of diabetes mellitus (known and unknown) was high in our study (6.7%). It corresponds to the upper margin estimates for the urban black Africa, ranging from 2 to 6% [
The growing trend documented by this work is part of the global evolution of progression of diabetes mellitus [
However, the prevalence we found remains lower than that reported by Oulad et al. (10%) to Marrakech (Morocco) [
In our study, the prevalence of unrecognized diabetes was 3.3%, about half of people with diabetes mellitus. This high prevalence of unrecognized diabetes is similar to that reported by Djrolo et al. (3.4%) in 2007 in Cotonou [
An association between diabetes mellitus and age was highlighted in the statement (p = 0.003). This is consistent with the observation that the incidence of diabetes mellitus increases with age especially after 40 years. We do not, for contrary, observe statistically significant differences in the prevalence of diabetes mellitus gender (p = 0.91). Sex does not appear as a risk factor of diabetes mellitus in our study, and the relative prevalence of diabetes was almost equal between the sexes (6.4% for men against 6.8% for women). This finding is similar to that reported by Djrolo et al. (4.7% versus 4.5%) in Cotonou in 2007 [
In our study, the difference in the prevalence of diabetes mellitus in hypertensive and non-hypertensive patients was statistically significant (p = 0.005). High blood pressure (hypertension) is a cardio-metabolic factor usually associated with the common form of type 2 diabetes, insulin resistance, central obesity and metabolic syndrome. This is consistent with the majority of the literature data. Indeed, Mbaye in Senegal [
The prevalence of diabetes mellitus in subjects with abdominal obesity was 10.3% (NCEP criteria) and 10.8% (IDF criteria). These rates are lower than those reported by Mbaye et al. St. Louis (Senegal) 52.0% (NCEP) and 73.6% (IDF) [
Many opinions demonstrate a strong association between parental heredity and the onset of type 2 diabetes [
This study documented a high prevalence of diabetes mellitus (6.7%) in an urban adult population of Porto- Novo in Benin, confirming the alarming increase in prevalence of the disease; half of the cases were unknown. These data confirm the literature data showing that diabetes mellitus is growing rapidly in developing countries; the urban environment is a highly diabetogenic environment.
, (2015) Prevalence and Risk Factors of Diabetes Mellitus in the Adult Population of Porto-Novo (Benin). Journal of Diabetes Mellitus,05,135-140. doi: 10.4236/jdm.2015.53016