Benign Prostatic Hyperplasia (BPH) is a non-cancerous condition where the prostate gland enlarges, common in aging men. While BPH primarily impacts the urinary system, it can also affect bowel movements. The close physical arrangement of organs in the male pelvis means that prostate enlargement can produce secondary effects on the adjacent lower gastrointestinal tract. Understanding this relationship is important, as both urinary and bowel changes may stem from the same underlying cause.
The Anatomical Relationship
The prostate gland is situated in the lower pelvis, beneath the bladder and surrounding the initial part of the urethra. Directly behind the prostate, separated by Denonvilliers’ fascia, lies the rectum, the final section of the large intestine. This anatomical proximity allows an enlarged prostate to influence bowel function.
As BPH progresses, the gland expands inward, compressing the urethra, but it also expands outward, particularly toward the back. This outward growth exerts direct mechanical pressure onto the anterior wall of the rectum, a flexible, muscular tube designed to store stool. Physical compression can impede the rectum’s ability to fully distend and function normally. This pressure interferes with the mechanics required for efficient stool movement and storage, depending on the extent and direction of the prostate’s growth.
Bowel Changes Linked to Prostate Enlargement
Pressure from an enlarged prostate on the rectum can alter a man’s bowel habits. The most common change is constipation, characterized by infrequent or difficult passage of hard stools. Prostate pressure can slow transit time, making it physically harder for stool to pass through the lower bowel.
Men may experience significant straining during defecation, which can sometimes worsen BPH urinary symptoms by increasing abdominal pressure. Another symptom is tenesmus, the persistent feeling of needing to empty the bowels, even immediately after a movement. While this connection exists, bowel issues are less common than urinary symptoms and often have other causes. Conversely, a rectum full of stool can press against the bladder, potentially worsening existing urinary symptoms.
Primary Urinary Symptoms of BPH
BPH is primarily defined by its impact on the lower urinary tract, categorized into voiding (obstructive) and storage (irritative) issues. These symptoms result from the enlarged prostate constricting the urethra. The resulting obstruction forces the bladder muscle to work harder, leading to structural changes in the bladder wall over time.
Obstructive Symptoms
Obstructive symptoms occur because the flow of urine is mechanically impeded. These include hesitancy (difficulty starting the stream) and intermittency (flow starts and stops). Men often report a decreased force and caliber of the urinary stream, post-void dribbling, and the sensation of incomplete bladder emptying.
Storage Symptoms
Storage symptoms arise from the bladder muscle becoming thicker and more sensitive due to the increased workload. This irritability manifests as urinary frequency (urination eight or more times a day) and urgency (a sudden, strong need to urinate that is difficult to postpone). Nocturia, the need to wake up during the night to urinate, is a common storage symptom.
Next Steps and Medical Evaluation
Any man experiencing urinary or bowel symptoms should seek evaluation, as these changes can signal various conditions beyond BPH. Diagnosis begins with a comprehensive medical history, often using the International Prostate Symptom Score (IPSS), a standardized questionnaire that classifies symptom severity.
Diagnostic Procedures
The physical examination includes a Digital Rectal Exam (DRE), where the doctor manually assesses the prostate’s size, shape, and texture from the rectum to determine enlargement and screen for other issues. Laboratory tests include a Prostate-Specific Antigen (PSA) blood test, which measures a protein produced by the prostate. Further diagnostic steps may include a urinalysis to rule out infection and a urine flow study to measure the speed and volume of urination.
Treatment Options
Understanding the root cause is necessary before initiating treatment. Options range from watchful waiting and lifestyle modifications to medication, such as alpha-blockers or 5-alpha-reductase inhibitors. Surgical options are typically reserved for severe cases or those unresponsive to medical therapy.