Increased long-term risk of new-onset diabetes mellitus in white-coat and masked hypertension.
OBJECTIVE
A sustained blood pressure elevation is associated with an increased risk of new-onset diabetes mellitus. Whether this is the case also in white-coat and masked hypertension is unknown.


METHODS
In 1412 individuals of the Pressioni Arteriose Monitorate E Loro Associazioni study stratified for sex and age decades, we measured office, home and 24-h ambulatory blood pressure together with fasting plasma glucose and other metabolic variables. This allowed to identify patients with white-coat, masked, sustained hypertension and true normotension.


RESULTS
Over a 10-year period, the increase in plasma glucose and the incidence of new-onset diabetes (plasma glucose > or =126 mg/dl or use of antidiabetic drugs) was significantly greater in individuals with white-coat and masked hypertension than in those with 'true' normotension (age and sex-adjusted risk 2.9 and 2.7, respectively), the increase being similar to that of sustained hypertensive individuals. The adjusted risk showed a marked increase when development of an impaired fasting glucose condition was also considered, and the results were similar when individuals reporting antihypertensive drug treatment were excluded or white-coat and masked hypertension were identified by office versus home blood pressure. The increased risk of new-onset diabetes become no more significant when data were adjusted for initial blood glucose and BMI, which, at a multivariate analysis, were the most significant predictors of this condition, with only a small although significant contribution of the initial blood pressure.


CONCLUSIONS
Thus, white-coat and masked hypertension are associated with a long-term greater progression of blood glucose abnormalities and an increased risk of developing diabetes. This is largely accounted for by the metabolic abnormalities that are frequent components of these conditions.
Clinica Medica, Dipartimento di Medicina Clinica, Prevenzione e Biotecnologie Sanitarie, Università Milano-Bicocca, Ospedale San Gerardo, Monza, Italy. giuseppe.mancia@unimib.it
Giuseppe
G
Mancia
Michele
M
Bombelli
Rita
R
Facchetti
Fabiana
F
Madotto
Fosca
F
Quarti-Trevano
Guido
G
Grassi
Roberto
R
Sega
D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000032:analysis; D018660:Blood Pressure Monitoring, Ambulatory; D003920:Diabetes Mellitus / Q000209:etiology*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000150:complications*; D008297:Male; D008875:Middle Aged; D012306:Risk
D001786:Blood Glucose