Diabetes and Hypertension: Preventing a Toxic Combination

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Diabetes mellitus and hypertension (high blood pressure) are significant health problems worldwide, but like cardiac disease and fatty liver disease, people of Asian Indian origin are disproportionately affected. Having both is a toxic combination and according to the World Health Organization, 347 million people suffer from diabetes worldwide and there are 62 million diabetics in India.

The prevalence of diabetes is predicted to double globally in 30 years. In the year 2000 there were 171 million and this will increase to 366 million by 2030 and the maximum increase will be from India. It is predicted that by 2030 diabetes mellitus may afflict up to 79.4 million individuals in India, while China (42.3 million) and the United States (30.3 million).

Preliminary results conducted by the Indian Council of Medical research (ICMR) has shown that a lower proportion of the population are affected in some of the states of Northern India (Chandigarh 0.12 million, Jharkhand 0.96 million) as compared to states such as Maharashtra (9.2 million) and Tamil Nadu (4.8 million)

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As for hypertension, one billion people have high blood pressure in the world and between 31 to 76 million Indians are affected. Both diabetes and hypertension can go unrecognized for many years in the absence of proper medical screening and both are major risk factors leading to death (from heart disease, stroke, chronic kidney failure, and infection). Sadly, both of these diseases are largely preventable through improved diet (less food and healthier food) and regular exercise.

Diabetes prevention and high blood pressure prevention should be at the forefront of every nation's health care priorities, as prevention greatly diminishes health care expenditures and human suffering in the long run. Diabetes and high blood pressure are also treatable even in their early stages, emphasizing the need for timely health screening and intervention if necessary.

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Indians succumb to diabetes and hypertension and die from their complications at younger ages (on average, ten years earlier) compared to people in economically privileged countries. In addition, Indians living abroad, even after several generations, retain their risk for these diseases, suggesting an as of yet undiscovered genetic predisposition.

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The costs to Indian society are staggering, with 2.6 million deaths per year just from coronary artery disease alone.

Diabetes and hypertension also increase the risk of stroke, fatty liver disease, kidney failure, blindness, and gangrene (necessitating limb or digit amputation), so the overall number of deaths and amount of suffering is much higher.

It has been estimated that almost 20% to 60% or even more of diabetic complications are due to associated hypertension. Also, the prevalence of hypertension in diabetic individuals appears to be 1.5 to 3 times higher than in normal similar age age-matched groups. People with both diabetes and hypertension have approximately twice the risk of cardiovascular disease like heart attack and stroke.

Both these diseases are more common among males, the aged, and unmarried, and those who are less educated, and earn less are also at higher risk. It is not clear as to whether the place of residence is associated with diabetes and hypertension in combination.

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Causes of Diabetes and Hypertension

There are two main types of diabetes mellitus-

Type I diabetes (10% of cases) is caused by an autoimmune attack of the body's own immune system on the cells in the pancreas that produce insulin (the Islets of Langerhans). Type I diabetes is associated with an earlier age onset and severe symptoms, always requiring insulin injections for management.

Type II diabetes (90% of cases) is caused by poor diet and lack of physical activity resulting in the body's resistance to normal levels of circulating insulin.

There are genetic components to both types, but Type I diabetes is considered to be more genetically driven and Type II diabetes is thought of more as an environmental/lifestyle disease. Eating too much food (especially foods with excess sugars and carbohydrates) and lack of regular physical activity are the major causes accounting for the high prevalence of Type II diabetes worldwide and these issues are the major factors driving diabetes prevention education.

The cause of hypertension is unknown in 95% of cases. This type is referred to as "essential" or "primary" hypertension. Secondary hypertension occurs when there is a known cause, such as atherosclerotic narrowing of the arteries supplying blood to the kidneys (renovascular hypertension), thyroid disease, or adrenal gland tumors. Often these underlying causes of hypertension can be treated or even cured if proper medical attention is sought. For "primary" hypertension, even though the underlying cause is unknown, diet, physical activity, and some genetic predisposition are significant risk factors, just as in the case with Type II diabetes. For instance, excessive salt intake and inadequately managed emotional stress (a manifestation of insufficient exercise) are major contributors to hypertension. High blood pressure prevention can be readily achieved by strict adherence to a healthy diet and regular exercise.

Hypertension is extremely common in patients with type 2 diabetes and they usually require two or more drugs to treat their hypertension. Despite combination drugs to treat hypertension, a number of diabetics may not achieve the target blood pressure goals of ¡Ü130/80 mm Hg. It is very important in diabetics with hypertension to achieve target blood pressure to reduce morbidity and mortality of diabetes mellitus.

Symptoms of Diabetes and Hypertension

Both diabetes and hypertension are asymptomatic in their early stages, so it is important to seek routine medical attention on a regular basis (i.e., an annual "well visit" physical examination by your primary care doctor).

Significant diabetes is associated with:

• Frequent urination
• Excessive thirst
• Blurry vision
• Constant fatigue
• Sexual dysfunction
• Sudden weight loss
• Obesity
• Poor wound healing or frequent genitourinary infections

Excessively high blood sugar levels can cause coma and acidosis (high blood acidity) whereas extremely low blood sugar levels can cause weakness, dizziness, sweating, and even death if not quickly treated.

Hypertension, when severe, can cause:

• Headache
• Anxiety
• Facial flushing
• Sweating

However high blood pressure is almost always asymptomatic. High blood pressure is, therefore, frequently referred to as a "silent killer".

Symptoms associated with damage to vital organs because of hypertension, such as chest pain, transient blindness ("amaurosis fugax" indicating cerebrovascular disease), or nausea/fatigue/decreased urination (associated with kidney failure) are consequences of longstanding, undiagnosed disease.

Diagnosis of Diabetes and Hypertension

Routine tests can diagnose these two conditions. However urine tests ¨C to look for protein in the urine (micro-albuminuria) should be done regularly. The presence of protein in the urine not only signifies a higher risk of developing diabetic kidney disease but also indicates higher incidence of cardiovascular events and death.

Diabetes can be diagnosed by a simple blood test to measure the amount of glucose (or "sugar") in the bloodstream. A fasting blood glucose level is more accurate because glucose levels can often be transiently elevated in normal people shortly after eating. An even more sensitive test is an oral glucose tolerance test, where glucose levels are measured in response to a known quantity of ingested glucose.

Insulin levels or "C-peptide" levels can be studied to help distinguish Type I from Type II diabetes, as levels will be low in the former and normal in the latter. Also, the "hemoglobin A1C" level (a sugar coated hemoglobulin molecule) is measured to identify the average blood glucose level over prolonged periods of time. This test helps to guide changes in therapy and is also an indicator of how compliant a person is with taking their diabetes medicines.

Hypertension is most simply measured with either a manual or automated blood pressure cuff. Even non medical personnel can be taught how to measure blood pressure manually, but the automatic cuffs are more popular because they are less prone to error (they should, however, frequently be checked for calibration).

It is important not to rely on a single blood pressure reading. A normal blood pressure reading can be influenced by one's hydration status (dehydration causes low blood pressure) or level of anxiety (a visit to the doctor can cause "white coat syndrome", or nervousness and elevated blood pressure) and not necessarily be representative of underlying disease. Many people, especially athletes and women, will have lower pressures as a baseline.

More sophisticated imaging tests are required to diagnose secondary hypertension (e.g., angiogram for renovascular hypertension or MRI/CT for adrenal tumors), but these should not be pursued unless abnormalities on basic blood chemistry tests (creatinine, sodium, potassium, etc.,) are first detected.

Treatment for Diabetes and Hypertension

Lowering blood pressure to less than 130/80 mm Hg should be the primary goal in the management of the hypertensive diabetic patients. Usually a combination drug is required to treat the hypertension to achieve the target blood pressure.

Type I diabetics uniformly require regular and frequent insulin injections to maintain normal blood glucose levels. Subcutaneous (underneath the skin) insulin pumps are available to provide constant insulin infusion adjustments, but the glucose sensing technology available at this point does not yet allow for true "real time" insulin infusion adjustments.

Pancreas transplantation is an option and is often performed in concert with renal transplantation ("combined kidney/pancreas transplant") and the results are quite good (70% ten year survival). Although pancreas transplant is a cure for diabetes Type I, it is reserved for highly selected, "near perfect" cases because the option of insulin replacement is often less morbid than the risks of a major surgery and subsequent lifelong immunosuppression. A final treatment option for Type I diabetics is panreatic islet cell infusion, but this therapy must be regarded as still in its experimental phase and not a cure for diabetes given the currently poor long term outcomes published in the scientific literature.

Type II diabetes can often be managed by dietary manipulation with or without oral medications to keep blood sugar levels in the normal range. Oral diabetes medicines include metformin, glipizide, glyburide, repaglinide, nateglinide, pioglitazone sitagliptin, and combinations thereof. More advanced cases require insulin injections. There is a growing body of evidence that weight loss surgery (gastric bypass or laparoscopic gastric banding) for morbidly obese individuals greatly improves existing diabetes, emphasizing the importance of exercise and dietary discretion in preventing or managing diabetes. Pancreas transplant is not recommended for Type II diabetes because the underlying problem is insulin resistance, so increasing the amount of insulin by transplanting another pancreas will not help.

Hypertension is successfully treated with a number of medications, often given in combination to achieve maximum efficacy and minimal side effects. Dietary measures (especially avoiding too much salt) and exercise are important in preventing disease and managing less severe disease, but medications are often needed. High blood pressure natural remedies, such as Ayurvedic herbs have been proposed as cures for hypertension, but rigorous scientific evidence is lacking for the management of hypertension other than the lifestyle changes mentioned above and scientifically proven allopathic medicines. Doctors should follow the well established hypertension management guidelines based on evidence from multiple clinical trials (e.g., NICE Guidelines) when prescribing an individual regimen and it is important that patients take their medicines as directed. If an unwanted side effect occurs, it is important that the patient discusses this with the doctor, as alternative regimens are available that can be tailored to an individuals need.

Hypertension and Diabetes are a toxic combination.

Both Hypertension and diabetes affect the same major target organs and the common denominator in these target organ is related to its vascular tree.

Heart Disease - these diabetic hypertensive patients are more likely to have enlargement of the left side ( left ventricular hypertrophy) and coronary artery disease compared to those who suffer from hypertension or diabetes alone.

Kidney, Eyes and Brain - The combined presence of hypertension and diabetes concomitantly accelerates the decrease in renal function, the development of diabetic retinopathy and the development of cerebral diseases.

Sexual Dysfunction - Both men and women have an increased risk of sexual dysfunction if they are diabetic hypertensive. What makes this worse is that most blood pressure drugs have impotence as their side effect.