Glycaemic control and family history of diabetes mellitus: is it all in the genes?

Abstract

Background: Type 2 diabetes mellitus (T2DM) is a familial condition with a strong genetic component. International studies have highlighted associations between a positive family history of diabetes (FHD) and poorer glycaemic control. No current data are available on this association within the context of HIV. Objectives: To determine a relationship between FHD and glycaemic control in patients living with DM (PLWD) in an HIV endemic area. Methods: Standardised clinic sheets were used from the DM clinic at Edendale Hospital, Pietermaritzburg, South Africa, from January 1, 2019 to December 31, 2019. Statistical analysis was done. Results: This study had 957 patients living with diabetes (PLWD); 498 (52.2%) had a positive FHD while 456 (47.8%) had no FHD. There were 146 (15.3%) HIV-infected patients; with 84 (57.5%) on a fixed dose combination (FDC) of anti-retroviral treatment (ART). Patients aged between 18 and 30 with a maternal FHD had significantly higher mean HbA1c levels than those without a maternal FHD (HbA1c: 10.80% vs. 9.72%, p = 0.025). Patients living with type 1 DM (PLWT1DM) in the HIV-uninfected cohort had significantly higher HbA1c levels than patients living with type 2 DM (PLWT2DM) (10.38% vs. 9.46%, p = 0.002). HIV-infected PLWD (PLWDH) on a FDC with a positive FHD had significantly higher HbA1c levels than those without a FHD (9.52% vs. 8.52%, p = 0.04). PLWDH with a positive maternal FHD on an FDC had increased HbA1c levels (9.81% vs. 8.55%, p = 0.009). Conclusion: Genes significantly affect glycaemic control among PLWD. PLWT1DM and PLWDH with a positive FHD (especially a maternal FHD) should be regarded as being in a higher risk category requiring more intensive lifestyle and therapeutic intervention to achieve optimal diabetes control. Our study suggests that a positive FHD affects glycaemia in PLWT1DM as significantly, if not more, than in PLWT2DM and recommends screening for a FHD to be incorporated in the comprehensive management of DM.