MATERIALS AND METHODS STUDY DESIGN
This is a prospective randomized study among adult Nigerian men with features of benign prostatic hyperplasia that attended the urology outpatient clinic of Lagos University Teaching Hospital.
STUDY LOCATION
The study was performed at the Lagos University Teaching Hospital; a tertiary institution with 761 beds serving the city of Lagos and South West Nigeria.
STUDY DURATION
Study duration spanned 18 months.
SAMPLING TECHNIQUE
Patients with diagnosis of benign prostatic hyperplasia evaluated by digital rectal examination, IPSS, PSA and ultrasound were assigned into three groups randomly after written informed consent had been obtained. Simple random sampling by balloting was utilized to allocate patients into each of the three groups. Each patient was given two tablets each. Patients in the monotherapy
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group were given placebo and active drug concurrently in order for them to remain blinded.
The first group were administered tamsulosin 0.4mg and a placebo (ascorbic acid 100mg daily).The second group were administered finasteride 5mg and placebo (ascorbic acid 100mg daily). Those in the third group were administered tamsulosin 0.4mg daily and finasteride 5mg daily. Patients on any of the drugs prior to this time were given a wash out period of 2 weeks.
The initial assessment of the patient was done by the author. The IPSS and basic uroflowmetry (peak flow rate (Qmax)) were performed at the commencement of the study and at 3 and 6 months. The IPSS questionnaires were self administered.
Uroflowmetry was performed using a rotating disc uroflometer (urodyne by medwatch ref-U2A1002-UK). The author supervised the uroflowmetry. Trans-abdominal ultrasound measuring prostate volume and post void residual of urine was performed at commencement and at 3 and 6 months. The ultrasound scan was performed by the same sonologist using the Belson 200 machine with a 3.5 MHz convex probe.
The patients were blinded to the specific group of drug given.
The same drug brand was provided to the patients. The brand of the drug provided was tamsulon xl with NAFDAC no A4-0901 and Finstal-5 with NAFDAC no
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A4-O891. Patients who developed intolerable drug side effects withdrew from the study.
Patients on therapy who developed acute urinary retention or other complication that necessitated catheterisation were withdrawn from the study.
The study was performed under the supervision of consultants in the unit.
SAMPLE SIZE CALCULATION
The sample size was calculated using the following formula62: N=2(z1-α/2+ z1-β)2
(d/σ)2
σ= standard deviation =36
α= 5% level of significance=0.05 1-β= power at 90%
d = difference observed in prostate volume17 of groups= 41 when α =0.05, β=0.10 then (z1-α/2+z1- β)2=10.51
Sample size was 16 by calculation but increased to 30 per group and 90 patients in all to account for attrition.
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INCLUSION CRITERIA
Men with diagnosis of BPH who satisfied these criteria were included:
Patients with IPSS score 8-19(moderate) who qualify for medical therapy.
Patients with PSA less than 10ng/ml with DRE suggestive of benign enlargement.
Patients with flow rate less than 15mls/s on uroflowmetry with a minimum voided volume of 150mls and voiding time of at least 30 seconds.
EXCLUSION CRITERIA
The following categories of patients were excluded:
Patients with BPH who were asymptomatic.
Patients who had mild symptom scores (0-7) on IPSS.
Patients with supine blood pressure less than 90/70 mmHg
Patients who had prior prostate or bladder surgeries
Men with history of chronic prostatitis or recurrent urinary tract infection.
Those who had two or more episodes of acute urinary retention requiring catheterization within a year of the study.
Patients with co-existing urethral stricture or bladder tumour or bladder stone or bladder diverticuli or neurogenic bladder.
Patients with BPH with clear indication for surgery.
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Patients with prior history of adverse reaction to the drugs or any of its constituents.
Patients with known impairment of liver or renal function.
WITHDRAWAL CRITERIA
The following were the criteria for withdrawal from the study:
Patients who developed acute urinary retention or haematuria requiring catheterisation during the study were deemed to have met a secondary endpoint in the study and withdrawn.
Patients who developed intolerable side effects were allowed to withdraw from the study.
Side effects were evaluated in the proforma at 3 and 6 months. Patients were free to withdraw from the study at any time they deemed fit even after their initial consent during the follow up period.
DATA COLLECTION TECHNIQUE
Data was collected with the aid of a predesigned proforma filled by the patient.
Proforma was administered to non-literate patients with the aid of translator.
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DATA ANALYSIS
All data generated during the study were analysed using SPSS statistical software version 20. The IPSS score, prostate volume, post void residual, peak flow rate was computed and presented in table and graphical format. The categorical data were cross-tabulated and chi square determined for significance. For numeric data, descriptive statistic was analysed and thereafter analysis of variance done to determine significant difference in the mean between the different groups.
Student t-test was done to determine significant difference within the groups at completion of the study.
ETHICAL APPROVAL
Ethical approval was obtained from the hospital ethics committee on research.
LIMITATION
There was limited time for completing the study, thus the sample size was limited and follow up period was shorter than other similar studies. The results of the study were therefore restricted to short term outcomes.
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