Effect of diabetes duration and glycaemic control on 14-year cause-specific mortality in Mexican adults: a blood-based prospective cohort study

Abstract

SummaryBackgroundDiabetes is a cause of at least a third of all deaths in Mexican adults aged 35–74 years, with the excess mortality due mainly to vascular disease, renal disease, infection, and acute diabetic crises. We aimed to analyse the effect of diabetes duration and glycaemic control on death rate ratios (RRs) for these causes and to assess the relevance to cause-specific mortality of undiagnosed diabetes.MethodsAbout 100 000 women and 50 000 men aged 35 years or older from Mexico City were recruited into a blood-based prospective study between April 14, 1998, and Sept 28, 2004, and followed up until Jan 1, 2016, for cause-specific mortality. Participants who, at recruitment, reported any chronic disease other than diabetes and those who had missing data for HbA1c or diabetes duration were excluded. We used Cox models to estimate the associations of undiagnosed or previously diagnosed diabetes (almost all type 2) with risk of mortality from vascular disease, renal disease, and infection, exploring among those with previously diagnosed diabetes the independent relevance of diabetes duration (<5 years, ≥5 to <10 years, or ≥10 years) and HbA1c (<9%, ≥9% to <11%, or ≥11%). We also estimated the association of HbA1c with mortality in participants without diabetes at recruitment.Findings133 662 participants were aged 35–74 years and had complete data and no other chronic disease. 16 940 (13%) had previously diagnosed diabetes, 6541 (5%) had undiagnosed diabetes, and 110 181 (82%) had no diabetes. Among participants with previously diagnosed diabetes, glycaemic control was poor (median HbA1c 8·9% [IQR 7·0–10·9]), and was worse in those with longer duration of disease at recruitment. Compared with participants without diabetes, the death RRs at ages 35–74 years for the combination of vascular, renal, or infectious causes were 3·0 (95% CI 2·7–3·4) in those with undiagnosed diabetes, 4·5 (4·0–5·0) for the 5042 participants with a diabetes duration of less than 5 years, 6·6 (6·1–7·1) for the 7713 participants with a duration of 5 years to less than 10 years, and 11·7 (10·7–12·7) for the 4185 participants with a duration of at least 10 years. Similarly, the death RRs were 5·2 (4·8–5·7) for those with HbA1c less than 9%, 6·8 (6·2–7·4) for those with HbA1c of 9% to less than 11%, and 10·5 (9·7–11·5) for those with HbA1c of at least 11%. Diabetes was not strongly associated with the combination of deaths from other causes apart from acute glycaemic crises. Among participants without diabetes, higher HbA1c was not positively related to mortality.InterpretationIn Mexico, the rates of death from causes strongly associated with diabetes increased steeply with duration of diabetes and were higher still among people with poor glycaemic control. Delaying the onset of type 2 diabetes, as well as improving its treatment, is essential to reduce premature adult mortality in Mexico.FundingWellcome Trust, the Mexican Health Ministry, the Mexican National Council of Science and Technology, Cancer Research UK, British Heart Foundation,...

Diabetes and all-cause mortality, a 18-year follow-up study

“…In the current study, the rate of mortality increased with diabetes duration. Our finding is consistent with previous studies [19][20][21] ; In the Verona Diabetes Study (VDS), death rates rose in both sexes with increasing duration of diabetes 19 . In a cohort study, a10-yearlonger duration of diabetes was correlated with a 1.2-1.3 times increased risk of all-cause mortality in Australian patients with diabetes 20 .…”

“…In a cohort study, a10-yearlonger duration of diabetes was correlated with a 1.2-1.3 times increased risk of all-cause mortality in Australian patients with diabetes 20 . Another study in Mexico reported significantly increased rates of death from diabetes with duration of diabetes 21 . Longer duration of diabetes (equivalent to diagnosis of diabetes at younger age) increases the exposure to hyperglycaemia, which is correlated to an increased risk of complications 16,17,22 .…”

Duration of diabetes and cardiorenal efficacy of liraglutide and semaglutide: A post hoc analysis of the LEADER and SUSTAIN 6 clinical trials

“…The management of long‐standing type 2 diabetes remains an important challenge. In addition to the difficulties of maintaining glycaemic control, long duration of diabetes is associated with an increase in cardiovascular complications and progressive renal decline, which in turn contribute to heightened rates of morbidity and mortality in these patients . While much is known about the association of diabetes duration with rates of complications, considerably less is known about the details of the efficacy and safety of antihyperglycaemic agents, such as GLP‐1 analogues, as diabetes duration increases, particularly if GLP‐1 analogues have consistent cardiorenal efficacy across different durations of type 2 diabetes.…”

“…The duration of type 2 diabetes is an important determinant of cardiovascular and renal outcomes . However, less is known about whether antihyperglycaemic agents exert a consistent benefit on these outcomes as duration of type 2 diabetes increases.…”

Nephro Update Europe 2018

“…A recent, similar study from Mexico assessed the effect of diabetes on cause-specific mortality [12]. In low- and middle-income countries the prevalence and complications resulting from diabetes are expected to increase, but in Mexico there is already a 4-fold increase in the mortality risk with a diabetes diagnosis.…”