Shorter leukocyte telomere length is associated with risk of nonobstructive azoospermia.

ABSTRACT

OBJECTIVE: To determine the association between leukocyte telomere length and the risk of nonobstructive azoospermia (NOA). DESIGN: The mean leukocyte telomere length (LTL) among men with NOA, obstructive azoospermia (OA), and normospermic subjects was determined by quantitative polymerase chain reaction (PCR). We used logistic regression to investigate the association between LTL and the risk of NOA after adjustment for age and body mass index (BMI). Partial correlation analysis was also used to evaluate the relationship of clinical parameters with the mean LTL among men with OA and NOA. SETTING: Reproductive medicine center. PATIENTS(S) A total of 866 men, including 270 normospermic controls, 247 OA and 349 NOA patients. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Leukocyte telomere length. RESULT(S) The mean relative LTL of men with NOA was significantly shorter than that of those with OA and in normospermic controls (odds ratio [OR] 0.81, 95% confidence interval [CI] 0.64-0.98 vs. OR 0.92, 95% CI 0.70-1.24 vs. OR 0.99, 95% CI 0.83-1.22), respectively). Subjects with shorter telomeres (lowest tertile) had a significantly higher risk of NOA than those with longer telomeres (highest tertile). Interestingly, we also found that a low relative LTL was associated with poor efficiency of spermatogenesis using the Johnsen score after testis biopsy and histopathology in azoospermic patients, after adjusting for patient age and BMI. CONCLUSION(S) This is the first report that short LTL is associated with NOA, shedding light on an important biological pathway involved in the etiology of this form of male factor infertility.