Type 2 DIABETES: But what are its new complications?

A previous Australian study of 456,000 patients with type 2 diabetes followed for 7 years had already revealed that only 4 traditional complications of diabetes are now among the 10 main causes of excessive hospitalizations.

The new study examined patterns of hospitalization at the general (Australian) population level to identify emerging complications of diabetes and improve understanding and management of the disease.

The study involved analyzing data from approximately 50% of Australians diagnosed with type 2 diabetes and whose data were on the Australian Diabetes Registry. That is 456,265 diabetic patients, whose data were compared with those of more than 19 million controls without diabetes. The researchers were able to identify the main causes of hospitalization and compare their incidence with the same relative risk of hospitalization in the general population. Finally, the complications of diabetes were divided into 3 categories:

1. traditional complications which included vascular disease, kidney failure, retinopathy and cataracts, neuropathy, obesity, infections traditionally linked to diabetes (e.g. urinary tract infections) and procedural complications linked to well-known complications diabetes (eg amputation);
2. emerging complications which included liver disease, mental health disorders, various cancers (gastrointestinal, female sex organs);
3. infections less commonly associated with diabetes (eg respiratory infections, sepsis).

All other diagnoses were categorized as ‘complications not commonly recognized’.

The analysis reveals that:

• people with diabetes are more at risk of being hospitalized with most of these medical conditions than the general population, with some exceptions: prostate cancer, aortic aneurysms and wrist fractures;
• the main cause of excessive hospitalizations in men with diabetes is cellulitis, followed by anxiety disorders, iron deficiency anemia and diabetes, at least twice the risk of admission for these conditions vs in the general population;
• the leading cause of excessive hospitalizations in women with diabetes is iron deficiency anemia, followed by the traditional complications of urinary tract infections and cellulitis;
• still among diabetic women, high rates of excessive hospitalizations are noted for lesser-known complications, including depression, gastrointestinal disorders and asthma; hospitalizations for asthma are more than twice as likely in women with diabetes than in the general population.

Thus, non-traditional complications, including anemia, stress disorders, depression, and pneumonia, are among the main reasons people with type 2 diabetes are hospitalized more frequently than the general population.

Complications of type 2 diabetes are changing

• Only 4 traditional complications of diabetes (cellulitis, heart failure, urinary tract infections, and skin abscesses) are today ranked among the top 10 causes of hospitalization in diabetic patients;
• the incidence of traditional complications of diabetes, including heart attacks, strokes and amputations have decreased dramatically over the past 20 years due to the reduction and better control of risk factors ( including blood pressure, cholesterol, smoking and blood sugar control) and better preventive care and management,
• emerges a wide range of lesser-known complications, including infections (pneumonia, sepsis), mental health disorders and gastrointestinal conditions;
• major causes of death and disease such as cancer, liver disease and mental disorders are now appearing in people with diabetes;

“These less common diabetes and mental health complications are becoming the leading causes of hospital admissions. They cause significant burdens that sometimes exceed the better known complications says lead author Dr Dee Tomic of the Baker Heart and Diabetes Institute (Melbourne).

These new complications are linked to better management of the disease

The emergence of these new complications indeed reflects the improvements in the management of diabetes. Diabetic patients live longer, which makes them vulnerable to a wider range of complications. However, the emergence of mental health disorders and infections such as sepsis and pneumonia will place an additional burden on health systems and should be factored into treatment protocols.

Mental health disorders are an emerging complication of type 2 diabetes, confirms the lead author, Dr Dianna Magliano, head of diabetes and public health at Monash University (Australia). The finding of the heavy burden of anemia in men and women with diabetes also suggests the possibility of a biological link between diabetes and iron deficiency.

These conclusions, which report observational associations rather than cause and effect relationships, however, require confirmation by a better controlled longitudinal study (which excludes people with diabetes from the control group).