1. ANTIHYPERTENSIVE DRUGS
Many patients with hypertension need
more than 1 type of blood pressure reducing medication. This may be because
different drugs act at different times of the day. This differential action
has been shown by a study done at University of Melbourne, Australia.
In this study, 4 types of antihypertensive drugs were used:
1 Beta blocker - Atenolol
2 Angiotensin converting enzyme inhibitor (ACE inhibitor) - Perindopril
3 Calcium channel blocker - Felodipine
4 Diuretic - Hydrochlorothiazide
The subjects were 65 years or older with untreated hypertension. It was
a randomized double blind study, with small numbers (24 patients). Ambulatory
BP monitoring was done.
The results showed that all the 4 classes of drugs lowered the BP significantly.
Felodipine and hydrochlorothiazide showed increased reduction in systolic
blood pressure; the reduction was also consistent over 24 hours. On the
other hand, atenolol was more effective during the day while perindopril
was more effective during sleeping.
The decrease in BP during sleep may
be the reason that cardiac morbidity and mortality are more effectively
reduced by the ACE inhibitor group.
2. FERMENTED MILK PRODUCT REDUCES BP
In Finland, a fermented milk drink is being marketed as a non-drug approach
to reducing BP. The product appears to contain certain peptides (proteins),
which lead to angiotensin converting enzyme inhibitor activity. Other
reasons for the antihypertensive effect are also being looked for.
3. DECREASE IN NEPHRON NUMBER - IS IT THE CAUSE FOR PRIMARY HT
Primary hypertension is the commonest
form of hypertension in the world. No specific causes have been identified
yet, though many theories have been proposed. Now researchers at the University
of Heidelberg, Germany have proposed that primary hypertension may be
caused by a decreased number of nephrons, genetically determined. (The
nephron is the basic filtering unit of the kidneys).
They found that patients who had hypertension had roughly half the nephrons
of patients without hypertension and that their nephrons were also larger.
Of course, this is one more theory that has to be proved or disproved
with more evidence.