Aging societies have been progressing rapidly worldwide, and the trend of growing number of elderly individuals with various range of functional capacities even among the same generation has been accelerated. Owing to the lack of pertinent evidence, we investigated the relationship between psoas muscle atrophy and lower urinary tract symptoms (LUTS) in elderly female patients.

We retrospectively analyzed female patients aged ≥65 years who visited our hospital between 2008 and 2018. The psoas muscle index (PMI) was assessed by computed tomography (CT) and defined as psoas muscle area at the level of third lumbar vertebra divided by the total body surface area. Logistic regression analysis was used to assess the relationship of International Prostate Symptom Score (IPSS) with several variables, including PMI, body mass index, age, hemoglobin (Hb), albumin, and estimated glomerular filtration rate (eGFR). Receiver operating characteristic (ROC) curve analysis was performed to assess the diagnostic accuracy of variables. Patients with diabetes mellitus, neurological disease, acute cystitis, history of abdominal surgery, carcinoma, and pelvic organ prolapse and those receiving medication for LUTS were excluded. Moreover, only patients who underwent CT examination within 1 year before or after visiting our hospital were enrolled.

The study population comprised 158 elderly female patients. The number of patients in the ≥75 years (old age) and 65–74 years (pre-old age) age groups were 70 and 88, respectively. Lower levels of PMI and Hb showed a significant association with severe IPSS storage sub-score in the “old age” group; however, a significant relationship was not observed in the “pre-old age” group [Table]. Furthermore, none of the variables showed any significant relationship with the total IPSS and IPSS voiding sub-score in both age groups [data not shown]. In terms of diagnostic accuracy, ROC curve analysis of PMI and Hb indicated good predictive performance as markers of IPSS severe storage symptoms in the “old age” group [Figure].

Low muscle mass and anemia are known markers of sarcopenia [1]. In our study, both these variables were associated with severe storage symptoms in the “old age” group. In a previous study, aging-induced detrusor muscle change was associated with detrusor hyperactivity with impaired contractility (DHIC) [2]. Moreover, elderly individuals with sarcopenia were shown to exhibit detrusor overactivity or DHIC [3]. These theories may explain the observed association of lower levels of PMI and Hb with severe storage symptoms in the “old age” group in our study. We could not evaluate muscle function in this retrospective study, which is a study limitation; further studies are desired to explore this aspect.

Lower levels of PMI and Hb were found to be associated with severe storage symptoms in the “old age” group. Prevention of sarcopenia at a younger age may help control the future development of severe storage symptoms.

J Clin Gerontol Geriatr Volume 6, Issue 4, Pages 115-119, 2015
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