Variability of body weight, pulse pressure and glycaemia strongly predict total mortality in elderly type 2 diabetic patients. The Verona Diabetes Study.
BACKGROUND
Ageing is characterized by a decreased functional reserve, a concept defined as homeostenosis. We assessed the impact of long-term exposure to the average value (mean) or to the variability (coefficient of variation) of fasting glycaemia, body mass index (BMI) and pulse pressure on total mortality in a cohort of type 2 diabetic patients.


METHODS
Fasting glycaemia, BMI and pulse pressure values were collected over a period of 3 years in 1 319 type 2 diabetic patients who were subsequently followed up for 10 years. For each patient, the means and the coefficients of variation of fasting glycaemia, BMI and pulse pressure were computed. The adverse impact of these risk factors on total mortality was assessed in patients aged < 65 years (n = 565) and in those aged > or = 65 years (n = 754), separately.


RESULTS
During the 10 years of follow-up, 438 patients died. In younger diabetic patients, the means of fasting glycaemia [hazard ratio (HR) of III tertile versus I tertile = 2.11, 95% confidence interval (CI): 1.22-3.64], BMI (HR = 1.88, 1.12-3.14) and pulse pressure (HR = 2.36, 1.34-4.16) were independently associated with total mortality, while in older patients they were not. In contrast, the coefficients of variation of glycaemia (HR = 1.56, 1.17-2.08), BMI (HR = 1.34, 1.03-1.75) and pulse pressure (HR = 1.34, 1.03-1.74) independently predicted total mortality only in older patients.


CONCLUSIONS
Our findings suggest that the variability of fasting glycaemia, body weight and blood pressure (BP) is independently associated with an increased risk of all-cause mortality in older type 2 diabetic patients. Future studies are required to confirm the reproducibility of our findings.
Zoppini
Giacomo
G
Division of Endocrinology and Metabolic Diseases, University of Verona, Verona, Italy. giacomo.zoppini@univr.it <giacomo.zoppini@univr.it>
Verlato
Giuseppe
G
Targher
Giovanni
G
Bonora
Enzo
E
Trombetta
Maddalena
M
Muggeo
Michele
M
D017668:Age of Onset; D015415:Biomarkers; D001786:Blood Glucose / Q000032:analysis / Q000378:metabolism*; D015992:Body Mass Index; D001835:Body Weight; D002423:Cause of Death; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000401:mortality* / Q000503:physiopathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D007558:Italy; D008297:Male; D008875:Middle Aged; D010045:Outpatients; D011237:Predictive Value of Tests; D011674:Pulse; D012727:Sex Characteristics
D015415:Biomarkers; D001786:Blood Glucose; D007004:Hypoglycemic Agents