Source: Flickr user HazPhotos.

There are few diseases that get as much attention in the U.S. as cancer – and with good reason as it's a lethal disease in many instances which often doesn't have a cure. However, there's an equally dangerous disease that tends to run under the radar of most Americans: hypertension, which is more commonly referred to as high blood pressure.

Within the U.S., according to statistics from the Centers for Disease Control and Prevention, 67 million adults, or 31% of the population, have high blood pressure. Furthermore, almost one-in-three Americans have what's referred to as prehypertension, a condition where their blood pressure is above normal, but is not yet considered to be in the high blood pressure range.

Why is this concerning, you wonder? First, high blood pressure has an adverse effect on the healthcare system as a whole, costing the nation $47.5 billion each year. But more importantly, for the aforementioned 67 million adults, high blood pressure patients are at a higher risk of having a stroke or heart attack, dealing with chronic lung failure, or developing kidney disease. The CDC points out that approximately 1,000 people in the U.S. died each day in 2009 with high blood pressure being the primary or contributing factor of their death.

Five states where high blood pressure is the most prevalent
Although hypertension within the United States is widespread, as you could surmise from the above statistics, certain states tend to have a markedly higher hypertension diagnosis rate than the national average. Whereas the average incidence rate of high blood pressure is 31% within the U.S., the following five states in a Behavioral Risk Factor Surveillance System survey conducted in 2011 on hypertension awareness, all noted incidence rates of at least 38%.

  1. Alabama 40.1%
  2. Mississippi 39.3%
  3. Tennessee 38.7%
  4. Louisiana 38.4%
  5. Kentucky 38% 

Source: Centers for Disease Control and Prevention utilizing data from the Behavioral Risk Factor Surveillance System.

What's unique about these states? A diet higher in fat content could play a role, but the truth is that researchers can't predict who will develop high blood pressure throughout their lifetime and who won't, with any degree of certainty. However, that doesn't mean researchers don't have a good bead on what the risk factors are that are associated with developing high blood pressure. Risk factors include having diabetes, as well as being a smoker and/or overweight, eating foods that are high in sodium and low in potassium, and not getting enough exercise per the CDC.

There's good news, too!
Though hypertension can have devastating consequences, the good news is that we're moving in the right direction when it comes to reducing the death rate associated with the disease.

Source: Flickr user Dr. Farouk.

Based on two separate studies, the National Health and Nutrition Examination Survey I (NHANES I) which recruited adults between 1971 and 1975 and NHANES III, which enrolled adults between 1988 and 1994, the death rate among people with high blood pressure has declined between the two time spans from 18.8 per 1,000 person-years to 14.3 per 1,000 person-years. This dip can likely be attributed to a combination of improving hypertension education, as well as new and improved pharmaceutical products aimed at improving patients' quality of life and overall survival.

Even so, death rates are still markedly higher for patients with hypertension than those without. According to the more recent survey, NHANES III, death rates for patients with hypertension were 57% higher than those without, meaning there's still plenty of work left to be done to fight this terrible disease.

Improving patient outcomes remains a priority
To give you an even more encompassing idea of how focused the pharmaceutical community has been on fighting hypertension, as of 2010, three of the 10 most-written prescriptions in the U.S. were for blood pressure maintenance therapy.

Merck's (NYSE:MRK) Prinvil and AstraZeneca's (NYSE:AZN) Zestril, for example, are to forms of ACE inhibitors which work by dilating a patients' arteries and allowing blood to flow more freely throughout the body. ACE inhibitors are also used to treat congestive heart failure.

Source: Flickr user Caspar Diederik.

Another drug that's been improving patients' quality of life is Pfizer's (NYSE:PFE) Norvasc, which saw sales slip last year by 9% to $1.23 billion as it begins to lose patent protection in key markets. Norvasc is part of a group of drugs known as calcium-channel blockers which also dilate blood vessels and can reduce the force of the heart's contractions.

An oft-overlooked point within hypertension treatment is that a number of previously key drugs have moved well beyond their patent protection period. What this has done is allowed generic drug producers like Teva Pharmaceutical (NYSE:TEVA) to bring previously branded products to consumers at a fraction of their previous cost. The benefit is that these treatments are now considerably more affordable for a greater swath of the population.

This drug could be a game-changer
While I'm certainly encouraged by the progress being made in helping to curb hypertension-related deaths, I'm even more intrigued by one experimental therapy which could hold plenty of potential in improving patients' quality of life.

The developing drug in question is Novartis' (NYSE:NVS) LCZ696. As reported in August, LCZ696, when pitted in a head-to-head chronic heart failure study against Merck's Vasotec -- the most commonly prescribed heart failure medication, -- was shown to be statistically superior to Vasotec. Over a 27-month test period on some 8,400 chronic heart failure patients (which often have high blood pressure), there was an 18% reduction in deaths in the LCZ696 patient group compared to the Vasotec group. The drug also reduced the need for hospitalization by 21%.

I bring this up in the first place because Novartis is tinkering with the idea of testing LCZ696 as a direct treatment for hypertension. If these results carry over to the broader application of high blood pressure, some 67 million adults could be looking at a dramatic improvement in blood pressure control within a few years.

Here's what really matters
Regardless of who or where the next great blood pressure control medication comes from, it's clear that pharmaceutical companies need to make this under-the-radar killer among its top priorities. Continuing education of the American population on taking care of themselves will of course be important, but ongoing research into new pathways of treating hypertension will still be needed if the death rate associated with high blood pressure is to fall in the future. I remain hopeful that researchers' discoveries will lead to longer life expectancies as well as a healthier overall population.

Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

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