Urinary tract infections in postmenopausal women: Effect of hormone therapy and risk factors

Objective To assess the effects of hormone therapy on urinary tract infecti on frequency and to examine potential risk factors. Methods. We used data from the Heart and Estrogen/Progestin Replacement Stu dy, a randomized, blinded trial of the effects of hormone therapy on corona ry heart disease events among 2763 postmenopausal women aged 44-79 with est ablished coronary heart disease. Participants were randomly assigned to 0.6 25 mg of conjugated estrogens plus 2.5 mg of medroxyprogesterone acetate or placebo and followed for a mean of 4.1 years. History of physician-diagnos ed urinary tract infections and risk factors were assessed by self-report a t baseline and each annual visit. Results: Urinary tract infection frequency was higher in the group randomiz ed to hormone treatment, although the difference was not statistically sign ificant (odds ratio [OR] 1.16, 95% confidence interval [CI] 0.99, 1.37). St atistically significant risk factors for urinary tract infections in multiv ariable analysis included: women with diabetes on treatment (insulin OR 1.8 1,95% CI 1.40,2.34), oral medications OR 1.44, 95% CI 1.09, 1.90), poor hea lth (OR 1.34, 95% CI 1.14,1.57), childbirth (OR 1.38,95% CI 1.00, 1.90), va ginal itching (OR 1.63, 95% CI 1.07, 2.50), vaginal dryness (OR 1.30, 95% C I 1.04, 1.67), and urge incontinence (OR 1.51, 95% CI 1.30, 1.75). Urinary tract infections in the previous year were strongly associated with a singl e urinary tract infection (OR 7.00, 95% CI 5.91, 8.29) as well as multiple urinary tract infections (OR 18.51, 95% CI 14.27, 24.02). Conclusions: Oral hormone therapy did not reduce frequency of urinary tract infections. Potentially modifiable risk factors in postmenopausal women ar e different from those in younger women, and include diabetes, vaginal symp toms, and urge incontinence. (Obstet Gynecol 2001; 98:1045-52. (C) 2001 by the American College of Obstetricians and Gynecologists.).