The relationship between age and diabetes control in patients living with diabetes mellitus in low-to-middle income countries.

Abstract

Diabetes Mellitus (DM) is a chronic, metabolic disease characterised by raised blood glucose levels. In 2019, there were an estimated 463 million adult patients living with diabetes (PLWD), with this figure expected to reach around the 700 million mark by 2045. Patients living in low-income and middle-income countries comprise approximately 79% of global adult PLWD figures, with approximately 20% of these PLWD being older than 65 years. This illustrates that the burden of DM rests on the younger working-age population in low-to-middle-income (LMIC) countries. These patients living with type 1 and type 2 diabetes have reduced life expectancies of approximately 20 and 10 years, respectively. Unfortunately, this compounds the problem of further decreasing the life expectancy of the population of LMIC countries which are already being affected by communicable diseases like HIV infection. South Africa has the highest prevalence of human immuno-deficiency virus (HIV) in the world at 13% with many PLWD also being HIV-infected. With the effective roll-out of anti-retroviral treatment (ART), patients are also able to live longer and can develop diabetes mellitus as a result of longevity, ART and the HIV-infection itself. With the prevalence of both these conditions and the numbers of DM expected to rise, determining relationships in PLWD in an HIV-endemic area would offer better knowledge and allow for better strategies to be implemented to effectively manage a significant proportion of patients in our setting. A scoping review was conducted globally to identify associations between ‘age’ and ‘glycaemic control’ in HIV-infected PLWD. The review concluded that “varying data exists on the associations between glycaemic control and age in PLWD in the context of HIV infection (PLWDH). Further studies are recommended to determine associations in this regard, especially in LMIC where HIV and DM have a higher prevalence.” The lack of conclusive associations identified from the scoping review suggested that another study was warranted in an HIV-endemic region. A retrospective study was conducted among 957 PLWD of whom 146 patients were HIV-infected from the Edendale Hospital Diabetes Clinic, Pietermaritzburg, South Africa from 1 January 2019 to 31 December 2019. Statistical analysis was performed with a p value<0.05 being considered statistically significant. Our study showed that younger PLWD had poorer glycaemic control and were likely to develop diabetes-related complications later in life. Of note, older age was associated with improved mean glycated haemoglobin (HbA1c) levels after adjusting for glomerular filtration rate (GFR) [r=-0.141, p<0.001; (before adjustment: r=-0.108; p=0.001)]. In addition to this, PLWD with an HIV-infection who had a mean HbA1c>7% were significantly younger than those with HbA1c≤7% (47.38 years vs. 52.77 years, p=0.013). viii From this study, we evaluated associations between age and glycaemic control in PLWD has served to highlight that “more emphasis, in terms of diabetes education and management, needs to be placed in the younger age category of both PLWD and PLWDH”. This study, as well as future prospective studies, will assist with providing patients, healthcare workers and government with improved knowledge, thereby managing patients more effectively at any given age. Some of our recommendations from this study include: screening all patients for DM and implementing strategies to optimise glycaemic control and prevent complications; healthy diet to be implemented by patients of all ages; exercise as well as optimal pharmacological management and self-monitoring of glucose levels.