Abstract
In lifestyle-related diseases, such as cerebrovascular diseases, diabetes mellitus, and hypertension, all have lower urinary tract symptoms. In cerebrovascular diseases, the symptoms of overactive bladder such as urinary frequency, urinary urgency, and urge incontinence are prominent. In diabetes mellitus, half of the patients with diabetes have an overactive bladder. However, advanced peripheral neuropathy shows an underactive bladder such as presence of residual urine without the urge to urinate. Hypertension is not a specific disease showing lower urinary tract symptoms in itself. However, it has a negative influence on both urine voiding and collecting symptoms. Hypertension caused by increased concentrations of noradrenaline and dopamine during the daytime increase renal arterial resistance, decrease renal blood flow, and lead to insufficient daytime urine production. When catecholamines decrease at night, renal arterial resistance decreases and renal blood flow increases, allowing urine production to increase at night in order to excrete water stored during the daytime. It is also possible that an increase of the plasma catecholamine levels is not only related to nocturnal polyuria but also to diminished bladder capacity. The increase of plasma catecholamine levels influences the ascending limb of the micturition reflex in the spinal cord and induces the urge to urinate at lower bladder volumes. Furthermore, the increased plasma catecholamines act on the smooth muscle in the prostate gland, and narrow the prostatic urethra. If there is an obstructive bladder state, such as benign prostatic hyperplasia, the obstructive bladder state worsens to the high plasma catecholamine level. Obstructive bladder leads to overactive bladder.
