Hypothesis / aims of study
Benign Prostatic Hyperplasia (BPH) is associated with lower urinary tract symptoms (LUTS) and potential alterations in autonomic nervous system function, as reflected by heart rate variability (HRV). This study compares HRV parameters and symptomatic outcomes following Transurethral Resection of the Prostate (TURP) or treatment with the uroselective alpha-1A blocker tamsulosin (0.4 mg once daily)
Study design, materials and methods
Data from a prospective cohort of 242 men undergoing TURP and 210 men receiving tamsulosin were analyzed. HRV parameters (standard deviation of normal-to-normal intervals [SDNN], low-frequency/high-frequency [LF/HF] ratio, total power [TP], very low frequency [VLF]) and International Prostate Symptom Scores (IPSS) were assessed at baseline and 12 weeks. Propensity score matching (PSM) was used to address base-line differences in age, prostate volume, IPSS, and baseline SDNN. Inter-group com-parisons used ANCOVA with baseline as covariate.
Results
After 12 weeks, TURP was associated with substantially greater improvements in heart rate variability (HRV) compared to tamsulosin. In the TURP group, SDNN increased by 14.70 ms (40%; from 36.97 ± 22.80 to 51.67 ± 27.59 ms; p=0.032; Cohen’s d=0.58), LF/HF ratio decreased by 0.90 (55%; p=0.028; d=−0.76), total power (TP) increased by 1303 ms² (95%; p=0.025; d=1.12), and VLF increased by 810 ms² (85%; p=0.030; d=1.01). Corresponding changes with tamsulosin were more modest: SDNN +6.73 ms (18%; p=0.004; d=0.57), LF/HF −0.16 (8%; p=0.012; d=−0.27), TP +559 ms² (39%; p=0.006; d=0.93), and VLF +355 ms² (35%; p=0.010; d=0.82). Secondary p-values were adjusted using the Benjamini-Hochberg method. Inter-group differences were statistically significant by ANCOVA (p < 0.01 for all HRV parameters; partial η² = 0.12–0.22).
TURP also produced a larger reduction in IPSS (−10.2 points) compared with tamsulosin (−5.3 points; inter-group p < 0.001). Multivariate regression showed that change in SDNN was independently associated with IPSS improvement (standardized β = −0.42, p < 0.01). Propensity score matching (210 pairs) confirmed the superior HRV restoration and symptomatic benefit with TURP (all p < 0.01).
Interpretation of results
In the unmatched cohorts, TURP was associated with significantly greater improvements in heart rate variability (HRV) parameters compared with tamsulosin at 12 weeks. SDNN increased by 14.70 ms in the TURP group (95% CI: 1.3–28.1; p=0.032; paired Cohen’s d=0.58) versus 6.73 ms with tamsulosin (p=0.004; d=0.57). The LF/HF ratio decreased more substantially after TURP (−0.90; p=0.028; adjusted p=0.042; d=−0.76) than with tamsulosin (−0.16; p=0.012; adjusted p=0.018; d=−0.27). Greater increases were also observed in total power (TP: +1303 vs +559 ms²) and very low frequency (VLF: +810 vs +355 ms²), with significant inter-group differences by ANCOVA (p<0.01 for all HRV parameters; partial η²=0.12–0.22) (Tables 2–4). Baseline TP and VLF were lower in the TURP group (p<0.05).
Symptomatically, TURP produced a larger reduction in IPSS (−10.2 points; d=−1.94) than tamsulosin (−5.3 points; d=−1.02; inter-group ANCOVA p<0.001; partial η²=0.25) (Table 4). Voiding subscores improved more with TURP, and HRV changes correlated moderately to strongly with IPSS and QoL improvements in the TURP group (r=0.45–0.55) but more weakly with tamsulosin (Table 5). Multivariate regression showed that ΔSDNN independently predicted ΔIPSS (standardized β=−0.42, p<0.01; R²=0.28) and ΔQoL (β=−0.38, p<0.05).
Propensity score matching (210 balanced pairs, SMD<0.1) confirmed the superior effects of TURP on ΔSDNN (+13.8 vs +6.73 ms), ΔLF/HF, ΔTP, ΔVLF, and IPSS reduction (all p<0.01) (Table 6). Similar patterns were observed in the subgroup with prostate volume <50 mL.
Concluding message
In this observational study, TURP was associated with greater improvements in HRV parameters and symptoms than tamsulosin, potentially due to mechanical BOO relief. Findings are hypothesis-generating; randomized trials are needed for causality, long-term outcomes, and personalized strategies, possibly using HRV as a biomarker.