Optimal cut-offs of five anthropometric indices and their predictive ability of type 2 diabetes in a nationally representative Kenyan study

Knowledge, perceptions and practices towards diabetes risk in sub-Saharan Africa: a mixed-methods scoping review

OBJECTIVE

To synthesise current evidence on knowledge, perceptions and practices towards type 2 diabetes risk in sub-Saharan Africa.

DESIGN

Mixed-methods scoping review, which included 101 studies (seventy-three quantitative, twenty qualitative and eight mixed methods) from seven electronic databases.

SETTING

Sub-Saharan Africa, 2000-2023.

PARTICIPANTS

Men and women without diabetes with mean ages ranging from 20 to 63 years.

RESULTS

The majority of participants in most studies knew the three main diabetes modifiable risk factors - excess weight, unhealthy diet and physical inactivity. However, most people with excess weight in almost all studies underestimated their weight. Further, the self-described ideal body weight was between midpoint of normal weight and the upper limits of overweight in most quantitative studies and was described as not too skinny but not too fat in qualitative studies. In the majority of studies, participants reported low engagement in weight control, high regular sugar intake, and low regular fruit and vegetable intake but moderate to high engagement in physical activity. Barriers to reducing diabetes risk were social (e.g. societal perceptions promoting weight gain) and environmental (e.g. limited affordability of healthy foods, high accessibility of Western diets and lack of physical activity facilities).

CONCLUSION

There is a need for multicomponent type 2 diabetes prevention interventions that increase knowledge of identifying diabetes risk (e.g. what constitutes excess weight) and create social and physical environments that support healthy lifestyles (e.g. societal perceptions that promote healthy living, increased availability and affordability of healthy foods and physical activity facilities).

Association of BMI and incidence of type 2 diabetes in Saudi population

Objective

The study aims to identify the optimal body mass index (BMI) cut-off for obesity based on the risk of developing type 2 diabetes among the general population visiting primary health care in Saudi Arabia.

Methods

A cross-sectional study was conducted in Al-Ahsa City, Saudi Arabia, from January to June 2022. The study included Saudi citizens aged 35 and older who had not previously or currently been diagnosed with type 2 diabetes. Data were collected through electronic health records from 48 primary healthcare centers. The variables derived from medical records were age, gender, HbA1c, weight, and height.

Results

The BMI mean among nondiabetic, prediabetic, and diabetic groups were 29.6 ± 6.2, 31.2 ± 6.6, and 31.7 ± 6.9 kg/m2, respectively. The BMI of the prediabetic and diabetic males were 30.1 ± 6.3 and 30.5 ± 6.5 kg/m2, respectively, and the BMI of the pre-diabetic and diabetic females were 31.9 ± 6.6 and 32.8 ± 7 kg/m2, respectively.

Conclusion

The current study correlated the result of HbA1c levels with BMI cut-off values as a modifiable risk factor for developing type 2 diabetes among the Al-Ahsa population in Saudi Arabia. The BMI mean among nondiabetic, prediabetic, and diabetic groups were 29.6 ± 6.2, 31.2 ± 6.6, and 31.7 ± 6.9 kg/m2, respectively. This study provided a list of BMI values as cut-off points with their sensitivity and specificity measures so the policymaker could utilize them. The best cut-off point could be decided based on cost-effective analysis. Further studies in the future might help evaluate the efficacy of screening programs and the association between BMI and other types of diabetes.

Perceptions of diabetes risk and prevention in Nairobi, Kenya: A qualitative and theory of change development study

BACKGROUND

Type 2 diabetes is increasing in Kenya, especially in urban settings, and prevention interventions based on local evidence and context are urgently needed. Therefore, this study aimed to explore diabetes risk and co-create a diabetes prevention theory of change in two socioeconomically distinct communities to inform future diabetes prevention interventions.

METHODS

In-depth interviews were conducted with middle-aged residents in two communities in Nairobi (one low-income (n = 15), one middle-income (n = 14)), and thematically analysed. The theory of change for diabetes prevention was informed by analysis of the in-depth interviews and the Behaviour Change Wheel framework, and reviewed by a sub-set (n = 13) of interviewees.

RESULTS

The key factors that influenced diabetes preventive practices in both communities included knowledge and skills for diabetes prevention, understanding of the benefits/consequences of (un)healthy lifestyle, social influences (e.g., upbringing, societal perceptions), and environmental contexts (e.g., access to (un)healthy foods and physical activity facilities). The proposed strategies for diabetes prevention included: increasing knowledge and understanding about diabetes risk and preventive measures particularly in the low-income community; supporting lifestyle modification (e.g., upskilling, goal setting, action planning) in both communities; identifying people at high risk of diabetes through screening in both communities; and creating social and physical environments for lifestyle modification (e.g., positive social influences on healthy living, access to healthy foods and physical activity infrastructure) particularly in the low-income community. Residents from both communities agreed that the strategies were broadly feasible for diabetes prevention but proposed the addition of door-to-door campaigns and community theatre for health education. However, residents from the low-income community were concerned about the lack of government prioritisation for implementing population-level interventions, e.g., improving access to healthy foods and physical activity facilities/infrastructure.

CONCLUSION

Diabetes prevention initiatives in Kenya should involve multicomponent interventions for lifestyle modification including increasing education and upskilling at individual level; promoting social and physical environments that support healthy living at population level; and are particularly needed in low-income communities.

Strikes and Gutters: Biomarkers and anthropometric measures for predicting diagnosed diabetes mellitus in adults in low- and middle-income countries

The management of diabetes necessitates the requirement of reliable health indices, specifically biomarkers and anthropometric measures, to detect the presence or absence of the disease. Nevertheless, limited robust empirical evidence exists regarding the optimal metrics for predicting diabetes in adults, particularly within low- and middle-income countries. This study investigates objective and subjective indices for screening diabetes in these countries.

METHODS

Data for this study was sourced from surveys conducted among adults (aged 18 years and above) in seventeen (17) countries. Self-reported diabetes status, fifty-four biomarkers, and twenty-six core and twenty-eight estimated anthropometric indices, including weight, waist circumference, body mass index, glycaemic triglycerides, and fasting blood glucose, were utilised to construct lasso regression models.

RESULTS

The study revealed variances in diabetes prediction outcomes across different countries. Central adiposity measures, fasting plasma glucose and glycaemic triglycerides demonstrated superior predictive capabilities for diabetes when compared to body mass index. Furthermore, fasting plasma or blood glucose, serving as a biomarker, emerged as the most accurate predictor of diabetes.

CONCLUSIONS

These findings offer critical insights into both general and context-specific tools for diabetes screening. The study proposes that fasting plasma glucose and central adiposity indices should be considered as routine screening tools for diabetes, both in policy interventions and clinical practice. By identifying adults with or at higher risk of developing diabetes and implementing appropriate interventions, these screening tools possess the potential to mitigate diabetes-related complications in low- and middle-income countries.

Associations of waist-to-height ratio with the incidence of type 2 diabetes and mediation analysis: Two independent cohort studies

AIM

To assess the relationship between waist-to-height ratio (WHtR) and the incidence of type 2 diabetes (T2D)/impaired fasting glucose (IFG) and to explore to what extent these associations are mediated by blood pressure, lipids and other indicators related to liver and kidney metabolism.

MATERIALS AND METHODS

This study was based on a functional community cohort included 6109 participants which were divided into two sub-cohorts. One sub-cohort included participants with normal fasting glucose (n = 5563), another included IFG individuals at baseline (n = 546). Cox regression models were used to evaluate the relationships of WHtR with T2D/IFG. Four-year time-dependent receiver operating characteristic (ROC) curve and area under curve (AUC) were calculated to estimate the discriminatory power of WhtR and other anthropometric indices on T2D. Mediation analysis was performed to estimate which risk factors mediate the association between WHtR and T2D.

RESULTS

Significant positive associations were found between WHtR and the incidence of T2D/IFG in both sub-cohort. WhtR was a useful predictor of T2D (P < 0.05). Mediation analysis showed that HOMA-IR (0.45 %), SBP (5.10 %), triglycerides (11.02 %), creatinine (9.36 %) and combined kidney indicators (17.48 %) partly mediated the effect of WHtR on T2D in men. For women, this association was partly mediated by SBP (13.86 %), HDL (24.54 %), ALT (6.29 %), UA (22.58 %) and combined kidney indicators (39.51 %).

CONCLUSIONS

WHtR was an independent risk factor for the development of T2D and IFG. This association was partly mediated by HOMA-IR, SBP, lipids and other liver and kidney metabolism indicators.

Association between Three Waist Circumference-Related Obesity Metrics and Estimated Glomerular Filtration Rates

Studies that have assessed the associations between obesity and the estimated glomerular filtration rate (eGFR) have reported inconsistent results. This cross-sectional study was performed to investigate the associations between three waist circumference (WC)-related obesity metrics (waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), and waist-to-height^0.5 ratio (WHt.5R)) and eGFRs. This study included 2133 men and 3443 women who were older than 40 years with eGFRs ≥ 60 mL/min/1.73 m² from the Korean Multi-Rural Communities Cohort. We calculated the residual body mass index (BMI) to reduce multicollinearity among the obesity metrics and performed multiple linear regression. For both sexes, among the adjusted models, most of the general obesity metrics were significantly associated with eGFRs. Particularly for women, the WC-related and general obesity metrics had a stronger effect on eGFRs in the quartile models that included the BMI and the residual BMI, respectively. When WC-related obesity metrics had a stronger effect than the general obesity metric, for both sexes, WHtR showed a significant impact than WHt.5R and WHR on eGFRs. Reducing multicollinearity had an important role in assessing the obesity metrics’ association with eGFRs. Overall, applying the residual method in further studies might help with evaluating the obesity paradox on renal function.