Hypothesis / aims of study
Prostate growth and alopecia androgenetica (AGA) are both under influence of dihydrotestosteron (DHT). The most common etiology of voiding LUTS is an enlarged prostate mostly caused by benign prostate hyperplasia (BPH). Well documented factors in the pathogenesis of BPH and LUTS are aging, hormonal, and genetic factors. In Caucasian men, the prevalence of alopecia androgenetica is 30% at the age of 30, which increases to 50% at the age of 50 and 80% by 70 years. DHT can make prostates larger and men balder. Alpha-reductase converts testosterone in DTH which contributes to the miniaturization of hair follicles . The application of 5-ARI have been shown to be effective in the treatment of AGA. Since as well AGA and prostate growth causing LUTS are under influence of DHT, the objective of this exploratory study is to study the association of the AGA baldness score and prostate size. Moreover AGA and various other clinical, functional and personal parameters are analyzed that are used for assessing male storage LUTS. If an association would exist, a baldness score could be predictive of e.g. prostate size or other cause of storage LUTS. We hope that with the results of this study we can support physicians in the estimation of the prostate size without using invasive methods.
Study design, materials and methods
We looked at all subjects undergoing a Green Light Laser (GLL) vaporization of the prostate procedure for the treatment of male LUTS. Between 2006 and 2017, 822 patients underwent this procedure in our clinic. Of 177 out of 822 subjects in this database a personal identifying photograph of the head was available in their electronic patient file that could be used for scoring baldness. To the best of our knowledge, this method has not been used in any prior study. From these photographs we assessed the rate of hair loss according to the Norwood-Hamilton scale 7-8. For simplification and because precise scoring was difficult the AGA was scored in two categories: < 4 and => 4. We decided that an AGA score =>4 was classified as bald, whereas lower scores were regarded as not-bald. The scoring was performed by one of the researchers. In all patients the next items were collected: age, prostate volume measured by transrectal ultrasound, PSA, IPSS, free uroflowmetry parameters, filling- and pressure flow urodynamics. PSA was classified in 0–2.5 ng/ml, 2.5–5 ng/ml, 5–7.5 ng/ml, 7.5–10 ng/ml, >10 ng/ml. Statistical analysis was performed using SPSS 24.0.0.0 (IBM Corp). Categorical and ordinal variables where analyzed with the Chi-Squared test and Fisher Exact test.
Results
Mean patient age was 68 (47-87) years. Mean IPSS was 20 (1-35). 2% (n = 2) presented with mild lower urinary tract symptoms
(International Prostate Symptom Score <8), 45% of subjects (n = 49) with moderate lower urinary tract symptoms (International Prostate Symptom Score 8–9) and 53% of subjects (n = 57) presented with severe lower urinary tract symptoms (International
Prostate Symptom Score >19). 59.3% of subjects were classified as bald using the Norwood-Hamilton scale (AGA score). Mean prostate size (range) was 77,5 ml (21-245), mean Qmax was 9 ml/s (1-25), Mean PSA was 4,7 ng/l (0,3 -39). AGA score correlated with none of the other parameters. PSA and prostate volume correlated with the Schäfer obstruction classification. Qmax correlated with Schäfer classification and IPSS. IPSS correlated with QoL. Schäfer classification correlated with PSA, prostate volume, Qmax and age.
Interpretation of results
.As expected, in our study various LUT parameters correlated with each other. However we could not significantly identify an association between parameters like LUTS, prostate size, PSA and the presence of Alopecia Androgenetica.