The investigation aimed to estimate the prevalence and correlates of pre-diabetes and diabetes in a national population-based survey among 18-69 year-old persons in Zambia. The prevalence of diabetes (overall 7.2%, 7.5% in women and 6.9% in men) and pre-diabetes (8.8%) was similar among women globally (7.9%) and lower among men globally (9.0%),3 and was higher than in local studies in Zambia (3.5% diabetes4 and “impaired glucose level or diabetes” 4.0%5) and in Malawi (5.6% diabetes and pre-diabetes 4.2%),10 in Uganda (1.4% diabetes and 2.0% pre-diabetes 2.0%),11 Burkina Faso (5.8%),7 Ethiopia (3.3% diabetes)8 and in Guinea (5.7%).9 The increased rate of diabetes found in Zambia (lower-middle income country) may be explained by a greater change of lifestyle, older age structure and greater urbanization than in low-income other African countries (Burkina Faso, Ethiopia, Guinea and Malawi) and older studies in Zambia.13,22
The investigation showed a high prevalence of undiagnosed diabetes (77.3%), which seems to be higher than in Guinea (56%),9 in Uganda (70.5%),12 in Benin (68.0%),12 in Zambia (34.5%)4 and lower than in Burkina Faso (91.7%).12 The prevalence of treated diabetics in this study (9.4%) was lower than in most other African countries, e.g. Benin (32.0%), Kenya (27.7%) and South Africa (40.1%), except for Burkina Faso (7.3%).12 The prevalence of controlled diabetes among diabetics (17.1%) in this study was lower than in Benin (21.7%) and South Africa (21.4%), similar to Kenya (18.4%) and higher than in Burkina Faso (6.9%).12 The study found that urban dwellers had greater awareness, treatment and control of their diabetes than rural dwellers, while there were no sex differences. The lack of awareness, treatment and control among rural dwellers may be attributed to poorer health services access. “Most primary care facilities in Zambia do not routinely screen for cholesterol or diabetes.”21 By enhancing primary facilities to conduct blood glucose tests, especially in rural Zambia, 21 diabetes awareness, treatment and control may improve.
Consistent with former research,4,8-11 this investigation showed pre-diabetes and diabetes increased with age. In unadjusted analysis, the study showed that female sex was associated with pre-diabetes, but no significant sex differences were found in the adjusted analysis for pre-diabetes and diabetes. In a systematic review on sex differences of the prevalence of diabetes in Africa, in most countries no sex differences were identified.23 [Hilawe]. Rural residence and in unadjusted analysis lower education increased the odds for pre-diabetes. Some previous studies confirm the association between rural residence,24 lower education in high-income and not low- or middle-income countries22,24 and diabetes, while some other studies,8,25,26 found a higher prevalence in urban areas. A diabetes-screening programme may be introduced, particularly targeting the older age high-risk groups.26
Some studies found an association between psychosocial distress, such as suicidal behaviour,15,16 stress17,18 and passive smoking,19 increased the likelihood of diabetes, while in this study only in unadjusted analysis alcohol family problem was associated with diabetes, while the stress of family member die from suicide, suicidal ideation and passive smoking were not significantly with pre-diabetes and/or diabetes.
This survey found an association between hypertension, central obesity and in unadjusted analysis raised total cholesterol and pre-diabetes and diabetes. These findings are consistent with previous investigations,4,6,8,9,11 showing major “modifiable cardio-metabolic risk factors”.9 This “combination of cardiometablic risk factors calls for a multiple rather than single risk intervention approach in this population.”13
Several health risk behaviours, such as unhealthy diet, sedentary behaviour, physical inactivity, tobacco use and alcohol misuse have been found to increase the risk for diabetes,6,11,27-30 while in this study only physical inactivity and in unadjusted analysis alcohol dependence were associated with pre-diabetes, and in unadjusted analysis physical inactivity was associated with diabetes, and no significant association between sedentary behaviour, daily tobacco use and inadequate fruit and vegetable intake and pre-diabetes and/or diabetes was found.
Study limitations
This investigation was limited because of its cross-sectional design as well as the self-report of the interview data. The variable on household income had many missing values and could therefore not be included in the analysis.