Diabetes warning signs detected

Body chemistry changes that lead to type 2 diabetes begin several years before symptoms become apparent, research has shown.
The researchers pinpointed specific changes in blood glucose levels and sensitivity to the hormone insulin.
They hope this could eventually be used to help identify people at high risk of the disease earlier, meaning action can be taken to delay its progression.
The Lancet study was led by University College London.
It was presented to a meeting of the American Association of Diabetes.

Long-term condition caused by too much glucose in the blood
Occurs when not enough insulin is produced by the body for it to function properly, or when the body's cells do not react to insulin. This is called insulin resistance
Symptoms can be controlled by healthy eating, and monitoring blood glucose level
However, injections may eventually be required
The researchers followed 6,538 UK civil servants over almost 10 years, during which 505 cases of type 2 diabetes were diagnosed.
They examined how the volunteers' blood glucose levels and the capacity of their tissues to respond to insulin - known as insulin sensitivity - changed over time.
They also looked at how the insulin-producing beta-cells of the pancreas functioned over time.
Rapid acceleration
The researchers showed that in volunteers who did not develop diabetes changes in body chemistry occurred at a steady, even pace over time.
However, patients who developed diabetes showed a rapid acceleration in both fasting and post-meal blood glucose levels starting three years before they were diagnosed with the condition.
Insulin sensitivity decreased steeply during the five years prior to diagnosis among the diabetic group.
And their beta-cell function increased between years four and three prior to diagnosis, as their body tried to compensate for the raised glucose levels, but then decreased in the three years up to diagnosis.
The researchers said their work could help efforts to develop more accurate models to predict an individual's risk of developing type 2 diabetes.
They said most prevention studies focused on people in the earliest stages of disease, but by that stage changes to body chemistry were already well advanced.
Lead researcher Dr Adam Tabak said: "Our model may help detect people at high risk to develop diabetes, so we can better target these people to prevent the development of the disease.
"We believe that an earlier intervention - before the conventional prediabetes stage - could delay diabetes development substantially."
More work needed
However, in an editorial in the same journal, diabetes experts Dr David Matthews and Dr Jonathan Levy, from the University of Oxford, warn that much more work is needed.
They wrote: "Does this mean that we find those who are about to get diabetes - perhaps even three or four years ahead? We fear not.
"The sensitivity and specificity of the forward predictions would be poor.
"Now the hunt has to be intensified for the pathology that causes the decompensation that precipitates diabetes."
Pav Kalsi, of the charity Diabetes UK, said: "Although these markers provide a good indication of future type 2 diabetes the lack of sensitivity and specificity means we cannot know for certain, so we'd welcome further research into this promising area of study."
Judy O'Sullivan, of the British Heart Foundation, said: "This study provides better data than we have had before to show that those who are going to get diabetes have signs they are at risk for several years before the disease becomes clinically obvious.
"This reinforces the view that more careful and frequent earlier routine screening could lead to a significant gain in preventing or delaying the onset of the disease."