Articles

Metro Urology

Introduction

According to the World Health Organization (WHO) Body Mass Index (BMI )* criteria, more than 65% of us are overweight, and about 1 in 3 are obese.  Heart attacks, hypertension, cancers, stroke, arthritis and diabetes are only some of the illnesses linked to being overweight, making it the leading preventable cause of death and other serious health problems in the US.  Because high fat diets increase the amount of body fat, and obese people generally are less physically active, it can be difficult to separate the effects of diet, exercise and obesity in many of the studies currently available.  However, there is increasing recognition that excess weight is associated with certain urologic problems, which disproportionately affect men.
Traditionally, the definition of obesity has been >20% over ideal body weight, however the most common current measure of obesity is determined by the BMI, calculated by the weight (kg)/height (m2) ratio(see below):

Sexual Dysfunction in Men

Obesity is linked to the development of diabetes, hypertension and coronary artery disease, which along with smoking and aging, are the main risk factors for Erectile Dysfunction (ED). Because penile arteries are smaller in diameter than coronary arteries, the first manifestation of decreased blood flow can be ED, and thus it often is  an early marker for “silent” heart disease.  It is now clear that when a physician sees a patient whose main complaint is ED, he should be evaluated for cardiovascular risk factors including obesity.  Another distressing sexual problem obesity causes in men is a functional decrease in penile length due to an increase in lower abdominal adipose.

Prostate growth

Although the causes of Benign Prostate Hyperplasia (BPH) are less clear than ED, there appears to be a correlation with being overweight.  While not definitive, many studies have shown a link between an increase in prostate size and obesity through an unknown mechanism.  While BPH does not necessarily translate into urinary problems, there is a trend that larger prostates means  more  risk of urinary symptoms (frequency, urgency, getting up at night), urinary tract infections, catheterization, retention and possibly surgery.

Urologic cancers

Numerous reports have demonstrated an association between obesity and renal cancer, a tumor that is twice as common in men vs. women. The mechanism is unclear, but it may be a combination of the association excess adipose and impaired cellular defense mechanisms along with the prolonged exposure to a high fat diet.  The association of prostate cancer with obesity is less certain, but there also appears to be a link.  Many studies have demonstrated that a high fat diet is an independent  risk factor for prostate cancer, and some have shown that obesity is associated with development of higher grade and stage prostate cancers, especially in younger men.

Surgical problems

Being overweight complicates many urologic procedures for a variety of reasons.  While laparoscopic and endoscopic procedures are not as affected, most operations on obese patients can be more difficult and have longer operative times, increased blood loss,  and increased intraoperative and anesthetic complications.  Extracorporeal Shock Wave Lithotripsy (ESWL), a popular and noninvasive treatment of kidney stones, is less successful in overweight patients because the stone is harder to visualize and the shock waves are less effective.

Conclusions

Body weight is a relationship between genetics, diet and physical activity, and it can be difficult to control.  Yet most men don’t realize that some lifestyle choices can lead to obesity and  may contribute to some urologic problems reducing the chances of successful treatment.  Since the development of urologic diseases depends on many interrelated factors (diet, age, genetics and the environment), it can be difficult to establish exact risks. Furthermore, the relative effects of being mildly overweight vs. morbidly obese are not known.  More studies are necessary to better define these issues and also demonstrate  the benefits of  diet and/or weight loss in men who are at risk for urologic problems.