[Nfbmo] good news for diabetics

[Debbie Wunder]

According to a population-based study of 2 cohorts in the United Kingdom and 
in Canada, the overall excess mortality risk from having diabetes vs not 
having this disease has dropped by about half since the mid-1990s.

The collaborative work by researchers in Sweden, the United Kingdom, and 
Canada is published online June 20 inDiabetologia.

In 2009 compared with 1996, the excess risk for mortality in patients with 
diabetes vs patients without diabetes decreased from 90% to 51% in the 
province of Ontario, Canada and from 114% to 65% in a representative sample 
of patients seen in primary care in the United Kingdom.

"About 14 years ago, the excess mortality associated with diabetes was often 
quoted as a 2-fold increased risk; now it has gone down to about 50%," lead 
author Lorraine Lipscombe, MD, from Women's College Hospital and the 
University of Toronto, in Ontario, told Medscape Medical News.

For clinicians, "it's good news," she noted. "This is evidence that we are 
doing a better job of taking care of diabetes," and "we can counsel patients 
that we are better able to manage them and keep them healthy for a longer 
period."

How Does Diabetes Affect Survival in a Modern Cohort?

Dr. Lipscombe and colleagues say that a recent review of prospective studies 
suggested that diabetes was linked with an approximate 80% increased risk 
for mortality, but many of the data came from before 2000. Newer research 
hinted that this rate was much lower now.

To investigate this, she and her colleagues set out to look at contemporary 
rates of mortality and examine changes over time. They used 2 databases, one 
of around 10 million Ontario residents covered by a provincial healthcare 
plan and the other covering more than 3 million patients seen in 
primary-care practices in the United Kingdom who are part of 
<http://www.thin-uk.com/> The Health Improvement Network (THIN).

>From 1996 to 2009, the prevalence of diabetes in adults aged 20 and older 
increased from 5.4% to 11.4% in Ontario and from 3.2% to 5.9% in the United 
Kingdom (THIN population).

"The reasons for this discrepancy [between the 2 cohorts] are unclear but 
may be related to differences in factors known to influence the incidence of 
diabetes, such as screening programs, ethnicity, eating habits, or 
physical-activity patterns," the authors write, adding that further research 
is needed.

Dr. Lipscombe explained that they included diagnoses of both type 1 and type 
2 diabetes, but they were unable to differentiate between the 2.

The excess risk for mortality in patients with diabetes vs patients without 
diabetes fell over time for all age groups during the study period: it was 
approximately 25% to 40% lower in those below the age of 64 years and 50% to 
65% lower in those aged over 64 years.

Adjusted Mortality Rate Ratios for Adults With vs Without Diabetes in 1996


Age (y)

Ontario database

THIN UK database


20 - 44

1.98

2.30


45 - 64

2.48

2.60


65 - 74

1.45

1.46


> 75

1.63

1.75


Total

1.90

2.14



Adjusted Mortality Rate Ratios for Adults With vs Without Diabetes in 2009


Age (y)

Ontario database

THIN UK database


20 - 44

1.70

1.79


45 - 64

1.94

2.23


65 - 74

1.16

1.24


> 75

1.23

1.25


Total

1.51

1.65

By 2009, the excess risk for mortality in patients with diabetes compared to 
their age-matched peers without diabetes was 70% to 79% higher in 20- to 
44-year-olds, about double in 45- to 64-year-olds, and 15% to 25% greater in 
those aged 65 and older.

The oldest individuals were more likely to have other comorbidities, which 
may explain why, compared with younger people, they had a lower rate of 
mortality related to diabetes, Dr. Lipscombe suggested.

The decline in deaths related to diabetes was similar in men and women.

UKPDS Likely Influenced the Better Outcomes


"We're much more aggressive with glucose control, blood-pressure control, 
and lipid treatment, so that has probably led to healthier populations," she 
speculated. "We're [also] screening more often and detecting diabetes at an 
earlier stage."The overall narrowing in the mortality gap may reflect 
changes in practice guidelines that followed the 1998 United Kingdom 
Prospective Diabetes Study (UKPDS), which showed that intensive management 
of type 2 diabetes led to better outcomes, Dr. Lipscombe said.

This study was supported by the National Diabetes Surveillance System 
funding from Ontario's Ministry of Health and Long-Term Care and an 
unrestricted grant from AstraZeneca and Novo Nordisk Scandinavia. Dr. 
Lipscombe was supported by the Canadian Diabetes Association/Canadian 
Institute of Health Research (CDA/CIHR) Clinician Scientist Award and 
currently receives support from a CIHR New Investigator Award.