Fang J, Madhavan S, Cohen H, Alderman MH
Isolated diastolic hypertension: A favorable finding among
young and middle-aged hypertensive patients
Hypertension
(Sep) 26:377-382 1995
Long term prognosis of patients with narrow pulse pressure,
normal systolic blood pressure, but isolated diastolic
hypertension (IDH) has been unclear in the published literature.
In this epidemiological study, Fang et al examined 965 patients
with IDH (<160/>90 mm Hg) and compared the incidence of
myocardial infarction (MI) over an average 4.5 year follow up
with 595 patients with combined systolic/diastolic hypertension
(>160/>90 mm Hg). All patients were less than 60 years old.
Exact pharmacologic treatment data was not reported. Comorbid
conditions and associated risk factors and demographic
characteristics were identified and patients with SDH were
older, more often female, tobacco smokers, hyperlipidemic,
hyperglycemic, and had LVH by ECG criteria in comparison to IDH
patients. The authors claim to have corrected for these
obviously influential factors through a Cox multivariate
analysis.
Age adjusted incidence for MI per 1000 person-years
was 5.2 in the SDH group vs. 2.31 in the IDH group (RR 2.31 vs.
1.00 respectively, hazards ratio 2.11). Interestingly, no
patient with IDH and an initial systolic blood pressure less
than 140 mm Hg suffered an MI during the study period.
Furthermore, a wide pretreatment pulse pressure (held by
previous authors to predict cardiovascular risk) was found in
this study to have a linear and independent correlation with MI
(hazards ratio 1.54). An accompanying article in the September issue of
Hypertension by Blank et al
(26:383-389, 1995) suggests that auscultory technique in the setting
of a narrow pulse pressure overestimates "true" diastolic values
by 5 mm Hg or more, supplying some explanation for the findings
contained in this study. While MI appears less common with IDH
in comparison with SDH truly long term prospective data are still
unavailable.
(Narsipur)