OBJECTIVE:

To examine the association of components of the metabolic syndrome with lower urinary tract symptoms (LUTS), which often result from prostate enlargement and heightened tone of prostate and bladder smooth muscle.

DESIGN:

Third National Health and Examination Survey (NHANES III), from which LUTS cases and controls were selected.

SUBJECTS:

A total of 2372 men aged 60+ y who participated in NHANES III. LUTS cases were men with at least three of these four symptoms: nocturia, incomplete bladder emptying, weak stream, and hesitancy, and who never had noncancer prostate surgery. Controls were men without any of the symptoms and who never had noncancer prostate surgery.

MEASUREMENTS:

As part of NHANES III, an oral glucose tolerance test was carried out, glycosylated hemoglobin, HDL and LDL cholesterol, and triglycerides were measured, and history of diabetes mellitus and hypertension were assessed. Logistic regression was used to calculate odds ratios (ORs) after applying sampling weights.

RESULTS:

History of diabetes (OR 1.67; 95% confidence interval (CI) 0.72–3.86) and hypertension (OR 1.76; 95% CI 1.20–2.59) appeared to be positively associated with LUTS. The odds of LUTS increased with increasing glycosylated hemoglobin (P-trend= 0.005). No statistically significant associations between fasting or 2-h glucose or fasting insulin and LUTS were observed. However, men classified as having three or more components of the metabolic syndrome had an increased odds of LUTS (OR= 1.80; 95% CI 1.11–2.94).

CONCLUSION:

These findings support the role for metabolic perturbations in the etiology of LUTS.

Introduction

Men of older age often experience lower urinary tract symptoms (LUTS) that frequently are due to benign prostatic hyperplasia (BPH). Besides the observation that the prevalence of LUTS increases with age, not much is known about the risk factors for this bothersome condition. Based on the observation in a clinic-based study of 158 patients that an enlarged prostate is more often diagnosed in men who have components of the metabolic syndrome, such as noninsulin-dependent diabetes mellitus, hypertension requiring treatment, low HDL-cholesterol levels, higher fasting insulin levels, and obesity, Hammarsten et al 1 suggested that the development of an enlarged prostate might be the result of perturbations in insulin control and other aspects of the metabolic syndrome. Recently, in a population-based sample of African-American men aged 40–79 y, Joseph et al 2 reported that men with a diagnosis of diabetes mellitus or hypertension had a higher odds of having moderate to severe LUTS.