Investigation of the prevalence of prostatic hyperplasia in a multicenter community in Beijing: results of the BPC-BPH study Stratified multistage whole cluster unequal proportional random sampling method was used to select men over the age of 50 years as the study subjects, and the International Prostate Symptom Score (IPSS), abdominal ultrasound measurements of prostate volume and residual urine output, and determination of the maximum urinary flow rate were recorded, respectively. Results were analyzed by ANOVA using SPSS software and P<0.05 was considered statistically significant. Results The total number of study subjects meeting the criteria was 1644 males with a mean age of 64.5 years (50-93 years), all respondents had an IPSS score of (9.9±8.2), a mean prostate volume of (30.85±19.42) g, and a mean maximal urinary flow rate (Qmax) of (14.74±7.51) ml/s, and each of the three had a different correlations (correlation coefficients r 0.388, 0.262, -0.371, respectively). The prevalence of moderate-to-severe lower urinary tract symptoms was 50.8% (835/1644), and 69.7% (1164/1644) of the respondents had a total prostate volume of >20 g, with a Qmax <15 ml/s of 53.78% (883/1644). Conclusion: Lower urinary tract symptoms and prostate volume are positively correlated with age and maximum urinary flow rate is negatively correlated with age in men over 50 years old in Beijing. The prevalence of prostatic hyperplasia in this group was 26.82% (441/1644) based on the criteria of IPSS >7, prostate volume >20g, and Qmax <15 ml/s, and the prevalence of prostatic hyperplasia was increased compared with the past. Prostatic hyperplasia (BPH) is one of the common diseases affecting the quality of life of elderly men, and the prevalence increases with age; however, the prevalence of BPH varies from region to region due to differences in ethnicity, geographic location, study population, and research methods. So far, there is a relative lack of well-developed epidemiologic information on BPH in China; for this reason, we investigated the current status of BPH prevalence in the Beijing area and report the following. Objects and methods This study used stratified multistage cluster unequal proportional random sampling method, with streets as the main stratum, communities and administrative villages as the basic sampling units, and all communities and administrative villages constituting the sampling population. Streets were used as the main stratum, with neighborhoods and administrative villages as the secondary stratum. This approach is based on the following considerations: the prevalence rates within each stratum (community to community in urban areas, and administrative village to administrative village in suburban counties) are relatively similar among survey units, with less variation, so that random sampling can reduce sampling error; the boundaries of the strata are clearly defined, so that the demographic information is accurate, and duplications and omissions can be avoided in sampling. The study population consisted of men ≥50 years of age in the resident population of 15 communities in the urban and suburban areas of Beijing as of June 1, 2008, divided into four age groups: 50 years ～, 60 years ～, 70 years ～, and ≥80 years. Exclusion criteria 1, those with previous history of prostate, urethra and bladder surgery; 2, those with neurological disorders that might affect urinary function; 3, those with psychiatric disorders that could not be cooperated with; 4, those with a history of bladder and prostate tumors; 5, urethral stenosis as well as those who used medications that might affect the function of the lower urinary tract. The investigation included: recording the IPSS score to understand the lower urinary tract symptoms; abdominal ultrasound to measure the prostate volume and residual urine volume, determine the maximum urinary flow rate, and at the same time, perform the rectal examination (DRE) and prostate-specific antigen (PSA, ELISA) to exclude prostate tumors, and the present study was discussed and approved by the Ethics Committee for the record, and all the respondents signed an informed consent form. Statistical methods: SQL-Server was used to create a database, and the results of the survey were analyzed using SPSS 11.0 software. Continuous variables were expressed as χ±s and skewed distribution data were expressed as median (quartiles). Comparisons between multiple groups were analyzed by ANOVA, rank sum test was used when not conforming to normal distribution, and χ2 test was used for categorical variables. p<0.05 was considered statistically significant. RESULTS I. Population distribution of the study subjects and their communities A total of 1,656 subjects were investigated in this study, of which 1,644 subjects met the criteria, with an average age of (64.5±9.8) years old, and the composition of the population of the subjects and the target communities is shown in Table 1.The PSA of the subjects had an average of (2.75±1.84) ng/ml, and the DRE suggests that there is no malignant manifestation of the prostate gland. Second, the lower urinary tract symptoms IPSS score The average IPSS score (9.9±8.2) (95% CI9.5-10.2) in this group of the investigated population, the IPSS score of the four age groups of 50 years old ~, 60 years old ~, 70 years old ~, ≥ 80 years old, respectively, were: 6.3±6.5 (95% CI 5.8-6.8), 10.3±8.0 (95% CI9.6～11.1), 13.1 11.1), 13.1±8.1 (95% CI 12.4 to 13.9), and 15.6±8.5 (95% CI 14.017.1), and the difference in lower urinary tract symptoms between age groups was statistically significant (P<0.05), and the Pearson correlation analysis showed a correlation between IPSS scores and age (r=0.388, P<0.01). Lower urinary tract symptoms IPSS score 0-7 for mild, 8-19 for moderate, 20-35 for severe, the proportion of mild, moderate and severe lower urinary tract symptoms were 49.2%, 36.4% and 14.4%, respectively, and the results of the proportion of distribution of the degree of symptoms between the age groups are shown in Table 2, and the analysis showed that the difference of distribution of those with moderate and severe symptoms was statistically significant (P<0.01) and correlated with age (r=0.45, P<0.01). correlation (r=0.457, P<0.01). The IPSS scores for bladder irritation symptoms (2, 4, and 7 questions, i.e., urinary frequency, urgency, and nocturia) and urinary obstruction symptoms (1, 3, 5, and 6 questions, i.e., incomplete urination, interrupted urination, straining to urinate, and difficulty in holding in urination) were 4.49±3.63 and 5.36±5.44, respectively, and the scores for urinary obstruction symptoms were higher than those for bladder irritation symptoms (P<0.05, P=0.01, P<0.01). scores (P<0.05). Bladder irritation symptoms and urinary tract obstruction symptoms between age groups are shown in Table 3, which statistically showed that the difference between the comparison of bladder irritation symptoms and urinary tract obstruction symptoms between age groups was statistically significant (P<0.01), and the correlation analysis showed that the two were correlated with age (P<0.01, with correlation coefficients of 0.41 and 0.33, respectively). Analyzing the results of the IPSS questionnaire: the frequency of the 7 main symptoms was highest in nocturia (87.5%, 1438/1644), followed by dysuria (58.6%,963/1644), dyspareunia (51.9%,853/1644), thin urinary line (50.8%,835/1644), and interruption of micturition (40.8%,670/1644), The surveyed patients had difficulty in urinating (39.8%,654/1644), and difficulty in holding urine (38.4%,631/1644). The mean total prostate volume was (30.85±19.42) g. 69.7% (1164/1644) of the respondents had a total prostate volume of >20 g. The proportion of those with a total volume of >20 g in each age group was 61.4% (397/646), 75.1% (335/446), 76.5% (335/438) and 69.2% (79.2%). ) and 69.2% (79/114), and the prostate volumes of each age group are shown in Table 4.The statistics showed that the difference in prostate volume comparison between age groups was statistically significant (P<0.05), especially in those with volume >20g. Multiple correlation analysis showed that total prostate volume was correlated (P<0.01) with age (r =0.262), IPSS score (r=0.232), bladder irritation symptoms (r=0.197) and urinary obstruction symptoms (r=0.217). V. Maximum urinary flow rate and residual urine volume 1642 cases (99.87%) out of 1644 investigated cases underwent urinary flow rate measurement, and the average maximum urinary flow rate (Qmax) was (14.74±7.51) ml/s, of which the proportion of Qmax <15 ml/s was 53.78% (883/1642), and the proportion of Qmax <15 ml/s was increased with the increase of age (P<0.05). increased (P<0.05). The distribution of maximal urinary flow rate in each age group is shown in Table 5, and statistical analysis showed that Qmax correlated with age (r=-0.371), IPSS (r=-0.325), and prostate volume (r=-0.161) (P<0.01). Residual urine volume was measured in 1644 individuals and the median residual urine volume was 10 ml,of which 8.8% (144/1644) had residual urine >50 ml. Statistics showed statistically significant differences in residual urine comparisons between age groups (P<0.05), and there was a correlation between residual urine and age (r=0.249), IPSS (r =0.241), total prostate volume (r=0.167) and Qmax (r=-0.148) (P<0.01). The difference in residual urine volume among respondents with residual urine volume >50 ml was not statistically significant between age groups, but the percentage was significantly higher (P<0.01). The proportion of residual urine and residual urine >50 ml between age groups is specified in Table 6. VI.Prevalence of BPH Table 7 shows the prevalence of BPH and total prevalence of BPH in each age group according to different diagnostic bases.The total prevalence of BPH based on the diagnostic bases of IPSS>7+Qmax<15 ml/s+prostatic volume>20 g was 26.82% (441/1644), and the difference in the prevalence of BPH among age groups was statistically significant (P<0.01). The difference in the prevalence of BPH was statistically significant (p<0.05). DISCUSSION Clinical symptoms of BPH appear more often after the age of 50 years, and there is no universally recognized definition of BPH, and the prevalence of BPH has been reported differently in different countries and races due to differences in study populations and research methods. Lower urinary tract symptoms, prostate volume, and urinary flow rate are three important parameters in epidemiologic studies of BPH, and we investigated lower urinary tract symptoms, prostate volume, and urinary flow rate in middle-aged and elderly men over 50 years of age in Beijing to find out the prevalence of BPH in Beijing. The results of this survey showed that the proportion of men over 50 years old with moderate-to-severe lower urinary tract symptoms (IPSS>7) accounted for 50.8%, the proportion of total prostate volume>20g was 69.7%, and the proportion of maximal urinary flow rate <15ml/s was 53.78%. Statistical analysis of the correlation between the three and age had different degrees of correlation: the lower urinary tract symptoms aggravated, the prostate volume increased, and the maximal urinary flow rate decreased with the increase of age. The lower urinary tract symptoms, prostate volume, and maximal urinary flow rate increase with age. Although lower urinary tract symptoms are common in middle-aged and older men, the prevalence of moderate-to-severe symptoms varies, with a higher proportion of moderate-to-severe symptoms in Asian populations than in European and American populations, and the prevalence correlates with age. In the present study, the proportion of moderate-to-severe symptoms of lower urinary tract symptoms in men over 50 years of age was 50.8%, and in particular, the proportion of moderate-to-severe lower urinary tract symptoms in men over 60 years of age was significantly higher than in the United States and Japan. In the present study, lower urinary tract symptoms were also found to be significantly correlated with age, which is the same as in the national and international literature.Haidinger et al. investigated lower urinary tract symptoms and found that obstruction symptoms were more pronounced than bladder irritation symptoms in middle-aged and older men, and the prevalence rate was significantly correlated with age.The scores of urinary tract obstruction symptoms were higher than those of bladder irritation symptoms in the present study, and there was a significant correlation between them and age.The symptoms with the The symptoms with the highest frequency were nocturia and dysuria in order, which is the same as in national and international studies. Although BPH is the main cause of LUTS in middle-aged and elderly men, the sensitivity of lower urinary tract symptoms in diagnosing BPH was only 79%. In this survey, the proportion of IPSS >7 was 50.8%, but the proportion of IPSS >7 and prostate volume >20g was only 35.1%, so there were still about 15.7% of respondents with IPSS >7 who had a prostate volume ≤20g, and the correlation analysis showed that the weak correlation between the total volume of the prostate and the IPSS scores also indicated that the inconsistency between lower urinary tract symptoms and BPH. It is generally believed that BPH causes lower urinary tract symptoms with both irritation and obstruction factors. In the present study, prostate volume correlated with both bladder irritation and obstruction symptoms, and the correlation of obstruction symptoms was stronger than that of irritation symptoms suggesting that BPH is not only involved in the formation of the two symptoms, but also more closely associated with obstruction symptoms. Maximum urinary flow rate and residual urine volume are objective indicators for evaluating the patient’s urinary status, which is one of the criteria for the clinical progress of BPH. In the present investigation, we found that there was a correlation between maximal urinary flow rate, residual urine volume and age, indicating that urinary flow rate decreases and residual urine volume increases with age. In the survey, the proportion of Qmax <15 ml/s was 53.78%, while the proportion of Qmax <15 ml/s and prostate volume >20 g was only 40.27%, and the correlation between maximal urinary flow rate, residual urine and prostate volume was weak.