OAB Symptoms Linked to Elevated Serum Leptin

Elevation of serum leptin and a decrease in monocyte chemotactic protein-1 (MCP-1) levels are associated with overactive bladder (OAB) symptoms, according to new data presented at the American Urological Association 2011 annual meeting.

Pradeep Tyagi, PhD, of William Beaumont Hospital in Royal Oak, Mich., and colleagues conducted a pilot study to investigate the relationship between body mass index, serum adipokine levels, and OAB symptoms in men and women. The study group consisted of 40 men and women with and without symptoms of OAB randomly selected from the Boston Area Community Health (BACH) Survey, a population-based study of urologic symptoms. In the current study, the 40 subjects were matched by gender, age, and OAB symptoms status. Analyses of serum adipokines, blinded to OAB status, included leptin, MCP-1, interleukin-1b (IL-1b), interleukin-6 (IL-6), interleukin-8 (IL-8), nerve growth factor (NGF), and tumor necrosis factor-alpha (TNF-alpha).

The investigators found that elevation of serum leptin and a decrease of MCP-1 in subjects with OAB symptoms compared with controls.  However, serum levels of IL-1b, IL-6, IL-8, NGF, and TNF-alpha were 100-fold lower than leptin and MCP-1 without any quantitative difference between the two groups. Serum leptin levels were positively correlated with BMI.

“Elevated leptin levels in subjects with OAB symptoms are consistent with previous studies on urinary chemokines and support the hypothesis of obesity mediate inflammation of OAB,” the researchers concluded in a poster presentation.

The decrease of serum MCP-1 levels in association with OAB symptoms was in contrast to elevated MCP-1 levels in urine-based studies. The investigators theorize that the discordance between serum-based and urine-based tests may be due to the bladder as a proximate source of urinary MCP-1.