Relationship between a genetic predisposition to hypertension, blood pressure levels and pain sensitivity.
BACKGROUND
The aim of this study was to determine whether the degree of blood pressure elevation and/or a genetic predisposition to hypertension have a major role in determining a reduced pain perception in hypertensives. The reasons underlying the relationship between blood pressure elevation and pain perception mechanisms are not completely understood.


METHODS
One hundred and four untreated hypertensive patients (65 subjects with and 39 without a positive parental history of hypertension) together with a control group of 42 subjects (20 normotensive offspring of normotensive parents, and 22 normotensive offspring of hypertensive parents) were submitted to standard blood pressure evaluation, 24-h blood pressure monitoring and dental pain perception evaluation.


RESULTS
Both pain threshold and tolerance were found to be higher in hypertensive than normotensive subjects (P < 0.0001 and P < 0.015, respectively). Positive significant correlations were found between both 24-h systolic and diastolic pressure and the pain perception variables. When a 2 x 2 ANOVA test was performed, factoring for the effects of both blood pressure status and family history of hypertension on pain sensitivity, a significant effect was revealed only for blood pressure status. Moreover, after controlling for blood pressure by a covariate analysis, no significant difference was found between the subjects with or without hypertensive parents as regards pain perception variables.


CONCLUSIONS
Pain sensitivity is correlated to blood pressure levels whereas the parental history of hypertension per se does not affect the pain perception pattern. Thus, the degree of blood pressure elevation, more than a genetic predisposition to hypertension may influence the mechanisms leading to hypalgesia in hypertension.
Guasti
Luigina
L
Chair of Internal Medicine, Department of Clinical and Biological Sciences, Faculty of Medicine, University of Insubria, Viale Borri 57, Varese, Italy.
Gaudio
Giovanni
G
Zanotta
Danilo
D
Grimoldi
Paola
P
Petrozzino
Maria Rosaria
MR
Tanzi
Fabio
F
Bertolini
Andrea
A
Grandi
Anna Maria
AM
Venco
Achille
A
D000328:Adult; D000704:Analysis of Variance; D001794:Blood Pressure / Q000502:physiology*; D016022:Case-Control Studies; D003782:Dental Pulp / Q000503:physiopathology; D004558:Electric Stimulation; D005192:Family Health; D020022:Genetic Predisposition to Disease; D006801:Humans; D006973:Hypertension / Q000235:genetics*; D016014:Linear Models; D008297:Male; D008487:Medical History Taking; D008875:Middle Aged; D017288:Pain Threshold / Q000502:physiology*; D014098:Toothache / Q000503:physiopathology