Category: – CARDIOLOGY

Subject: – CAUSES HIGH BLOOD PRESSURE?

Author -Dr. Pavan Agrawal.

OUR EXPOSURES

When we think about what causes high blood pressure, a number of environmental exposures come to mind and are well-established influences of blood pressure. Diet is well known to do this with sodium intake the most well known cause as well as a diet low in fiber or vegetables. Excess alcohol has been implicated. Poor lifestyle in general will low levels of activity and being overweight are also important factors. A combination of these factors is felt to underlie the majority of high blood pressure and for this reason non-drug based interventions are critical when treating high blood pressure. Lets we will discuss many of these factors of what causes high blood pressure below

GENETICS

Most experts agree that there is likely a significant underlying genetic element to essential hypertension, the most common form of high blood pressure, however the truth is that when it comes to most people with hypertension, we haven’t quite worked out the genetic basis of what causes high blood pressure which is undoubtedly complex. This remains the intense focus of ongoing investigation. There are however well described genetic variants that are responsible for small subsets of hypertensive patients. In these rare subsets such as Liddle’s syndrome and others, mutations in single genes explains what causes high blood pressure.

WEIGHT

The relationship between ones bodyweight and blood pressure has been well established. Obese people for example, are much more likely to have high blood pressure. This has been demonstrated in multiple studies. In fact in these studies, the more overweight one is, the higher their blood pressure is likely to be. In fact if obese patients lose weight and return to a normal weight, they have a significantly reduced risk of becoming hypertensive.

SALTS

Interestingly not only high sodium levels, but also low potassium levels have been implicated in high blood pressure. In some debates, the role of sodium in causing high blood pressure has been controversial, however the medical community as a whole endorses care when it comes to sodium intake. Study after study has demonstrated the relationship between higher levels of sodium intake and high blood pressure, cardiovascular disease and stroke. This is even more the case in those considered to be salt sensitive such as the elderly and black patients or those with diabetes and kidney disease. It is the opposite case for potassium. Low potassium is related to higher blood pressure and also worse outcomes. In fact a higher potassium level may blunt the effect of sodium on blood pressure.

ACTIVITY AND FITNESS

The relationship between physical activity and blood pressure is well established. The more active a person is the less likely they are to have high blood pressure. This is not just the case for athletes since even relatively modest levels of activity are associated with lower levels of blood pressure. Higher levels of physical fitness may prevent high blood pressure, improve blood pressure control and lead to improved cardiovascular outcomes in general.

ALCOHOL

Alcohol consumption has been associated with higher levels of blood pressure and in the US may account for up to 10% of cases of high blood pressure.

DRUGS

Painkillers are common offending agents in worsening blood pressure control, the most common being the over the counter NSAIDS, aspirin and Tylenol. In fact these medications have been implicated in preventing response to some of the most commonly used blood pressure medications. With NSAIDS in particular the effect is felt to be kidney mediated and related to fluid retention. Another important over the counter medication to consider is a decongestant pill. The mechanism of this is likely stimulatory effects, such as that seen with diet pills. Also worth mentioning are some herbal supplements containing ephedra, steroids and licorice. In patients with high blood pressure its critical to review their existing medication list to ensure there are no offending agents.

SLEEP APNEA

Obstructive sleep apnea, particularly when untreated is strongly associated with high blood pressure. The severity of the sleep apnea is directly related to the severity of blood pressure elevation. For this reason, in patients with sleep apnea, particularly those with high blood pressure, evaluation and treatment of the sleep apnea is critical.

HORMONES AND SYNDROMES

Although more rare, it is important to consider certain medical conditions in patients with high blood pressure, particularly if there is a clinical concern or if there is resistance to the treatment of blood pressure. These include the conditions hyperaldosteronism, pheochromocytoma and Cushing’s disease.

DIABETES AND KIDNEY DISEASE

High blood pressure, kidney disease and diabetes all go hand in hand. Both diabetes and kidney disease are strongly associated with high blood pressure. Diabetes is strongly associated with development of kidney disease, as is high blood pressure. It is critical for any patient with these conditions, that each condition is treated aggressively as they are a critical part of what causes high blood pressure.