By Rebecca Jenkins
Younger, rather than older, age at type 2 diabetes diagnosis is associated with higher mortality and vascular disease risk, an Australian-led analysis of more than one million people suggests.
Age at diagnosis, adjusted for current age, was inversely associated with risk of all-cause death and vascular disease in the analysis of 26 studies investigating the effects of age at diabetes diagnosis on mortality and subsequent complications in 1,325,493 people with type 2 diabetes from Europe, North America and the Asia Pacific.
Each one-year increase in age at diagnosis was associated with a 4% decreased risk of all-cause mortality, a 3% decreased risk of macrovascular disease and a 5% decreased risk of microvascular disease, researchers reported in Diabetologia.
‘While earlier studies have assessed the effects of age at diabetes diagnosis on diabetes complications, to our knowledge, this is the first systematic review and meta-analysis exploring associations between age at diabetes diagnosis and subsequent outcomes,’ the authors said.
The pathogenesis of the long-term vascular complications associated with early- or late-onset type 2 diabetes was not well characterised, they added, and although the mechanisms for the development of complications may be similar, recent evidence suggested an accelerated course in people diagnosed with early-onset type 2 diabetes.
‘Proposed mechanisms include a longer lifetime exposure to the adverse diabetic milieu and/or early-onset type 2 diabetes representing an inherently more aggressive metabolic phenotype with rapid onset of beta cell failure and insulin resistance compared with late-onset disease,’ they wrote.
Lead author, endocrinologist Dr Natalie Nanayakkara, of Melbourne’s School of Public Health and Preventative Medicine at Monash University, said people diagnosed with diabetes at a younger age had a longer lifetime risk of developing significant complications.
‘Thus, achieving good blood sugar and risk factor control (such as healthy weight and normal blood pressure) is of particular importance across their lifespan,’ she said.
‘The difference in risk between younger and older people in terms of absolute versus lifetime risks of type 2 diabetes complications, should perhaps be recognised in diabetes management guidelines, with increased promotion of screening programs in older people with type 2 diabetes and a greater emphasis on preventive measures for younger people with type 2 diabetes.’
Rates of type 2 diabetes have increased in all age groups and virtually all countries over the past three decades, Dr Nanayakkara told Medicine Today, with a particularly worrying trend of increased rates in people aged 20 to 44 years.
Diabetologia 2021; 64: 275-287.