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BACKGROUND: Despite technical advancements, inflatable penile prostheses (IPPs) are inherently at risk of mechanical failure given their nature as hydraulic devices. AIM: To characterize IPP component failure location at the time of device revision and stratify by manufacturer: American Medical Systems (Boston Scientific [BSCI]) and Coloplast (CP). METHODS: A retrospective review of penile prosthesis cases from July 2007 to May 2022 was conducted, identifying men who underwent revision surgery. Cases were excluded if documentation did not denote the cause of failure or the manufacturer. Mechanical indications for surgery were categorized by location (eg, tubing, cylinder, or reservoir leak; pump malfunction). Nonmechanical revisions were excluded (component herniation, erosion, or crossover). Categorical variables were assessed with Fisher exact or chi-square analysis; Student t-test and Mann-Whitney U test were used for continuous variables. OUTCOMES: Primary outcomes included specific location of IPP mechanical failure among BSCI and CP devices and time to mechanical failure. RESULTS: We identified 276 revision procedures, 68 of which met inclusion criteria (46 BSCI and 22 CP). Revised CP devices were longer than BSCI devices (median cylinder length, 20 vs 18 cm; P < .001). Log-rank analysis revealed a similar time to mechanical failure between brands (P = .096). CP devices failed most often due to tubing fracture (19/22, 83%). BSCI devices had no predominant site of failure. Between manufacturers, tubing failure was more common in CP devices (19/22 vs 15/46 for BSCI, P < .001), while cylinder failure was more common among BSCI devices (10/46 vs 0/22 for CP, P = .026). CLINICAL IMPLICATIONS: The distribution of mechanical failure is significantly different between BSCI and CP devices; this has implications regarding the approach to revision surgery. STRENGTHS AND LIMITATIONS: This is the first study to directly compare when and where mechanical failure occurs in IPPs and to compare the 2 main manufacturers head-to-head. This study would be strengthened by being repeated in a multi-institutional fashion to provide more robust and objective evaluation. CONCLUSION: CP devices commonly failed at the tubing and rarely elsewhere, while BSCI devices showed no predominant failure site; these findings may inform decision making regarding revision surgery.
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Implante Peniano , Prótese de Pênis , Masculino , Humanos , Reoperação , Estudos Retrospectivos , Boston , Implante Peniano/métodos , Falha de PróteseRESUMO
BACKGROUND: There is lack of consensus about the effectiveness of neoadjuvant platinum-based chemotherapy in patients with micropapillary variant urothelial carcinoma (MVUC) prior to radical cystectomy. We studied the association between neoadjuvant chemotherapy (NAC) and pathologic response (PR) among patients with micropapillary versus non-variant bladder urothelial carcinoma (UC). METHODS: We queried the National Cancer Database to identify patients with localized UC and MVUC from 2004 to 2017. We restricted our analysis to patients who underwent radical cystectomy with or without NAC. We compared clinical, demographic, and pathologic characteristics associated with NAC. We used multivariable logistic regression and propensity score matching to examine the association between NAC and the occurrence of a pathologic complete response (pT0) and pathologic lymph node positivity (pN+). Kaplan Meier analyses and Cox proportional hazards models were used to assess overall survival (OS). We performed analyses among subsets of patients with clinical stage II (cT2) disease, as well as the entire cohort (cT2-T4). RESULTS: We identified 18,761 patients, including 18,027 with non-variant UC and 734 patients with MVUC. Multivariable analysis revealed that NAC use was associated with greater odds of pT0 (9.64[7.62-12.82], P<0.001), and the association did not differ significantly between MVUC and non-variant UC. In a propensity matched analysis of patients with MVUC, NAC use was associated with higher odds of pT0 (OR 4.93 [2.43-13.18] P<0.001), lower odds of pN+ (OR 0.52 [0.26-0.92] P=0.047) and pathologic upstaging (OR 0.63 [0.34-0.97] P=0.042) in all stages. Similar findings were observed with cT2 disease. No significant association was seen between NAC and OS with MVUC (HR 0.89 [0.46-1.10] P=0.63), including the subset of patients with cT2 (HR 0.83 [0.49-1.06] P=0.58). CONCLUSIONS: NAC is associated with similar pathologic and nodal responses in patients with localized MVUC and non-variant UC. Improvements in pathologic findings did not translate into OS in this retrospective hospital-based registry study.
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Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Humanos , Carcinoma de Células de Transição/tratamento farmacológico , Carcinoma de Células de Transição/cirurgia , Carcinoma de Células de Transição/patologia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/cirurgia , Neoplasias da Bexiga Urinária/patologia , Bexiga Urinária/patologia , Terapia Neoadjuvante , Estudos Retrospectivos , Estadiamento de Neoplasias , Cistectomia/efeitos adversos , Quimioterapia AdjuvanteRESUMO
There is a paucity of management recommendations for patients with aggressive Diffuse large B cell lymphoma (DLBCL) of the bladder. A 57-year-old male patient presented with lower urinary tract symptoms underwent flexible cystoscopy and then bladder tumor biopsy. Through immediate staging CT scan, tumor and bone biopsies he was diagnosed with a 16 cm Stage IVa high-grade DLBCL. He was treated with DA EPOCH with only a partial response and was transitioned to R-ICE. For rarer presentations of bladder cancer during diagnostic cystoscopy there should be no delay in tumor imaging and involving medical oncology in early treatment decision making.
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Background and Objectives: The National Cancer Database (NCDB) captures nearly 70% of all new cancer diagnoses in the United States, but there exists significant variation in this capture rate based on primary tumor location and other patient demographic factors. Prostate cancer has the lowest coverage rate of all major cancers, and other genitourinary malignancies likewise fall below the average NCDB case coverage rate. We aimed to explore NCDB coverage rates for patients with genitourinary cancers as a function of race. Materials and Methods: We compared the incidence of cancer cases in the NCDB with contemporary United States Cancer Statistics data. Results: Across all malignancies, American Indian/Alaskan Natives subjects demonstrated the lowest capture rates, and Asian/Pacific Islander subjects exhibited the second-lowest capture rates. Between White and Black subjects, capture rates were significantly higher for White subjects overall and for prostate cancer and kidney cancer in White males, but significantly higher for bladder cancer in Black versus White females. No significant differences were observed in coverage rates for kidney cancer in females, bladder cancer in males, penile cancer, or testicular cancer in White versus Black patients. Conclusions: Differential access to Commission on Cancer-accredited treatment facilities for racial minorities with genitourinary cancer constitutes a unique avenue for health equity research.
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Neoplasias Testiculares , Bases de Dados Factuais , Feminino , Humanos , Incidência , Masculino , Fatores Raciais , Neoplasias Testiculares/epidemiologia , População BrancaRESUMO
INTRODUCTION: Bladder cancer care has been increasingly concentrated in high-volume metropolitan medical centres (ie, "regionalisation" of care). We aimed to assess the potential role of geographic factors, including facility region and distance to treatment centre, as determinants of neoadjuvant chemotherapy (NAC) delivery in patients with non-metastatic urothelial muscle-invasive bladder cancer (MIBC) using nationally representative data from the United States. METHODS: We queried the National Cancer Database to identify patients with cT2-cT4a, N0M0 urothelial MIBC who underwent radical cystectomy (RC) from 2006 to 2015. Patients who received radiation therapy, single-agent chemotherapy, adjuvant chemotherapy or systemic therapies other than multi-agent chemotherapy were excluded. Multivariate logistic regression analysis was performed to identify independent predictors of receiving NAC. RESULTS: A total of 5986 patients met the criteria for inclusion, of whom 1788 (29.9%) received NAC and 4108 received RC alone. Younger age, increased Charlson-Deyo score, increased cT stage, increased annual income, increased distance from cancer treatment centre, treatment at an Academic Research Program or Integrated Network Cancer Program and a later year of diagnosis were independently predictive of NAC receipt. Older age, Medicare insurance and treatment in the East South Central or West South Central regions were independently associated with decreased odds of NAC receipt. CONCLUSIONS: Distance to treatment centre and United States geographic region were found to affect the likelihood of NAC receipt independently of other established predictors of success in this quality-of-care metric. Access to transportation and related resources merits consideration as additional pertinent social determinants of health in bladder cancer care.
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Neoplasias da Bexiga Urinária , Idoso , Quimioterapia Adjuvante , Cistectomia , Humanos , Medicare , Músculos , Terapia Neoadjuvante , Invasividade Neoplásica , Estudos Retrospectivos , Estados Unidos/epidemiologia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/cirurgiaRESUMO
This narrative review synthesizes current evidence on the medical management of nocturnal polyuria, including antidiuretic replacement therapy as well as other emerging modalities, with particular emphasis on areas of active investigation and future research directions. Relative to earlier formulations, the pharmacological profiles of novel desmopressin acetate nasal spray and orally disintegrating tablet formulations appear favorable in optimizing the balance between efficacy and safety. Additionally, several highly selective small-molecule arginine vasopressin 2 receptor agonists are under active development, while appropriately timed short-acting diuretics, pharmacotherapy for hypertension, nonsteroidal anti-inflammatory drugs, and sex hormone replacement therapy are also a focal point of extensive ongoing nocturnal polyuria research. Emerging laboratory technologies now make feasible a sub-stratification of nocturnal polyuria patients into substrate-based phenotypes for individualized treatment. An increasingly refined understanding of the pathogenesis of nocturnal polyuria, and arginine vasopressin dysregulation in particular, has also introduced new opportunities for point-of-care testing in patients with nocturnal polyuria.
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Background: Primary small cell carcinoma of the kidney (PSCCK) is exceedingly rare and data on disease characteristics and outcomes are sparse. This study examines a nationally-representative cancer registry to better characterize PSCCK. Methods: We queried the National Cancer Database to identify patients with histology-confirmed PSCCK from 2004 to 2015. Adjusted Cox proportional hazards regression and Kaplan-Meier analyses were employed to assess predictors of mortality and estimate median survival time, respectively. Results: A total of 110 patients were included (47:53% female:male, 77% ≥60 years of age, 86% Caucasian). Significant predictors of mortality included female sex, age 60-69 years, treatment at an Integrated Network Cancer Program, stage cM1, and lack of surgical and chemoradiotherapy treatment. Independent protective factors were high socioeconomic status and treatment at an Academic Research Program. The estimated median overall survival time was 9.31 (95% CI 7.28-10.98) months for all patients. No differences in estimated survival time were observed across individual treatment modalities among those patients who underwent treatment (p = 0.214). Conclusions: PSCCK is an aggressive malignancy with a median survival time of less than one year. Future studies that correlate clinical tumor staging with specific treatment modalities are needed to optimize and individualize management.
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PURPOSE: Recent literature has separately identified multiple determinants of the use of neoadjuvant chemotherapy (NAC) and adherence to pelvic lymph node dissection (PLND) guidelines in the management of non-metastatic bladder cancer. However, such NAC/PLND analyses tend not to account for the other modality, despite the fact that NAC may impact the extent of dissectible lymph nodes. We aimed to determine the predictors of adequate PLND in patients with non-metastatic urothelial muscle-invasive bladder cancer (MIBC) undergoing radical cystectomy (RC) following receipt of NAC. METHODS: We queried the National Cancer Database to identify patients from 2006-2015 with cT2-cT4a/N0M0 urothelial MIBC who underwent RC and were pre-treated with NAC. Multivariate logistic regression analysis was used to identify independent predictors of undergoing an adequate PLND (defined as > 8 nodes). RESULTS: A total of 1518 patients met the criteria for inclusion (74.4% underwent adequate PLND). Adequate PLND was associated with treatment at an academic research facility (OR 2.762 [95% CI 2.119-3.599], p < 0.001). The likelihood of adequate PLND was significantly decreased in patients of older age (0.607 [0.441-0.835], p = 0.002 for age 70-79 years; 0.459 [0.245-0.860], p = 0.015 for age ≥ 80 years), a Charlson-Deyo score of 1 (0.722 [0.537-0.971], p = 0.031), and those who were uninsured (0.530 [0.292-0.964], p = 0.038). CONCLUSIONS: Established predictors of PLND may not necessarily be generalizable to all patients undergoing treatment for bladder cancer. The interplay between PLND and NAC merits further study, particularly in view of recent literature calling into question the survival benefit of PLND in patients pre-treated with NAC.
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Carcinoma de Células de Transição/cirurgia , Excisão de Linfonodo , Neoplasias da Bexiga Urinária/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células de Transição/tratamento farmacológico , Carcinoma de Células de Transição/patologia , Quimioterapia Adjuvante , Bases de Dados Factuais , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Invasividade Neoplásica , Estudos Retrospectivos , Estados Unidos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologiaRESUMO
PURPOSE: We aimed to determine the potential relationship between atherosclerotic cardiovascular disease (ASCVD) score, which equates to 10-year risk of atherosclerotic cardiovascular events, and functional bladder capacity (FBC) among men in the outpatient urology setting. METHODS: We secondarily analyzed voiding diaries from men aged 40 to 79 years with nocturia. Patients with a history of cardiovascular disease or who had nocturnal polyuria were excluded. Patients were stratified by whether they met the high-risk ASCVD threshold (≥ 20%) following current cardiology consensus guidelines and assessed for the presence of small FBC (24-h maximum voided volume ≤ 200 ml). Logistic regression analyses were employed to explore associations between small FBC and ASCVD. RESULTS: Eighty-four men (median ASCVD score 18.4 [IQR 12.8-26.9] %, age 66 [61-71] years, body mass index [BMI] 29.4 [26.4-32.7] kg/m2) were included, of whom 36 (42.9%) were high-risk and 48 (57.1%) fell below the high-risk threshold. High-risk patients were more likely to have small FBC (23 [63.9%] vs. 14 [29.2%], p = 0.002). ASCVD risk predicted small FBC on univariate analysis (p = 0.002). No such effect was observed with age (p = 0.116), BMI (p = 0.523), or benign prostatic obstruction (p = 0.180). The association between ASCVD risk and small FBC persisted on multivariate analysis after controlling for BMI and benign prostatic obstruction (p = 0.002). No significant predictors of small FBC were observed when age, a major determinant of ASCVD risk and independent correlate of small FBC, was substituted for ASCVD score (p = 0.108). CONCLUSIONS: Small FBC is related to a higher predicted cardiovascular event rate in men with nocturia.
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Aterosclerose/fisiopatologia , Bexiga Urinária/fisiopatologia , Adulto , Idoso , Doenças Cardiovasculares/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Medição de Risco , MicçãoRESUMO
Radical cystectomy (RC) is associated with significant morbidity. Neuraxial analgesia is recommended by enhanced recovery after surgery guidelines, but largely supported by evidence extrapolated from colorectal surgery outcomes. We synthesized current evidence regarding short- and long-term outcomes associated with neuraxial analgesia versus patient controlled non-neuraxial analgesia following RC. PubMed, Embase, and Cochrane databases were searched for relevant studies published up to May 2020. Studies reporting complications, length of stay (LOS), pain score, opioid usage within 72 hours, overall survival, cancer-specific survival, and recurrence rate were included. Of 550 identified studies, 9 met criteria for inclusion. Four studies demonstrated a higher percentage of 90-day complications in the neuraxial analgesia cohort. Out of 6 studies reporting information regarding LOS, 4 demonstrated no improvement in LOS in the neuraxial cohort. A reduction in 72 hours post-RC opioid usage was observed in 2 out of 3 studies with available data. Information regarding post-RC pain scores were variable up to 3 days post-RC. One out of 2 studies with available data reported a significant association between neuraxial analgesia and an earlier time to recurrence. No significant associations were seen with respect to overall survival or cancer-specific survival. A majority of low-to-moderate quality evidence demonstrates neuraxial analgesia is associated with a higher rate of complications, variable information regarding pain control, no improvements in LOS, and no significant association with long-term oncological outcomes. Further research regarding the incorporation of nonopiate-based analgesic modalities into RC ERAS protocols is warranted.
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Analgesia Epidural , Analgesia Controlada pelo Paciente , Cistectomia , Dor Pós-Operatória/prevenção & controle , Cistectomia/métodos , Humanos , Resultado do TratamentoRESUMO
PURPOSE: Pathologic upstaging in renal cell carcinoma (RCC) is common and confers a significant risk of poor surgical and survival outcomes. Preoperative predictors of upstaging are of great clinical relevance but empirical evidence specific to racial minorities remains scarce. METHODS: National Cancer Database (NCDB) analysis of T3a-specific upstaging among White, African-American, Hispanic and Asian Pacific Islander (API) patients with AJCC cT1N0M0 RCC who underwent partial or radical nephrectomy between 2010 and 2015. Independent preoperative predictors of tumour upstaging were identified using multivariate logistic regression analyses. RESULTS: A total of 81 002 patients met the criteria for inclusion (5.6% T3a-specific upstaging). Increased age, increased Charlson-Deyo comorbidity index, clinical stages cT1b and unspecified cT1, and increased Fuhrman nuclear grade were identified as independent risk factors for upstaging. Independent protective factors for upstaging were younger age, female sex, African-American race and papillary, chromophobe, and unspecified RCC histologic subtypes. Significant risk factors and protective factors within individual racial subgroups were highly consistent with those observed in the overall study sample. All independent factors identified on race-specific subgroup analyses were significant in the same direction relative to the overall study sample. Variables found to be non-significant in the overall study sample remained non-significant across all racial subgroup analyses. CONCLUSION: The present study of nationally representative data found no clinically significant differences in upstaging risk across individual racial subgroups relative to the overall study sample. Preoperative factors that can be used to predict pT3a-specific tumour upstaging in CT1N0M0 RCC likely persist across different racial groups.
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Carcinoma de Células Renais , Neoplasias Renais , Carcinoma de Células Renais/cirurgia , Bases de Dados Factuais , Feminino , Humanos , Neoplasias Renais/cirurgia , Estadiamento de Neoplasias , NefrectomiaAssuntos
Noctúria , Neoplasias da Próstata , Humanos , Masculino , Noctúria/epidemiologia , Noctúria/etiologiaRESUMO
Nocturia is generally considered a urological condition, but may be an indicator of cardiovascular disease, as prior studies have found associations with cardiovascular risk factors as well as clinical and subclinical markers of coronary artery disease. This study aimed to explore potential associations between nocturia and abdominal aortic calcification (AAC). We analyzed 2013-2014 National Health and Nutrition Examination Survey dual energy x-ray absorptiometry-derived AAC data and concurrent interview data on kidney conditions from respondents aged 40-80 years. AAC was defined as a score ≥ 1 on the 24-point semi-quantitative AAC scale. Nocturia was defined as an average of ≥ 2 voids per night. Three incremental multivariate logistic regression models controlling for (1) age, (2) sex, race, and BMI, and (3) hypertension, diabetes mellitus, and smoking history were used to determine whether nocturia predicted AAC. These models were and modified to exclude age and/or sex to perform age- and/or sex-specific sub-analyses, respectively. Complete data were available from 2,945 participants (29.1% AAC, 31.4% nocturia). On univariate analysis, the association between nocturia and AAC was significant in women (OR 1.77 [95% CI 1.37-2.29], p < 0.001), but not in men (1.14 [0.74-1.76], p = 0.531). Multivariate analysis showed nocturia was an independent predictor of AAC in women in Models I-II (ORs 1.49-1.58, p ≤ 0.032) but not Model III (1.37 [0.90-2.09], p = 0.133). Stratification by age revealed a strong univariate association among women aged 50-59 (3.88 [1.97-7.61], p < 0.001), which persisted across all multivariate models (ORs 4.05-4.41, p ≤ 0.001). The presence of nocturia is an important clue of AAC in women, especially those middle-aged.
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Noctúria/complicações , Calcificação Vascular/diagnóstico , Adulto , Idoso , Aorta Abdominal , Doenças da Aorta/complicações , Doença da Artéria Coronariana/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Inquéritos Nutricionais , Fatores de Risco , Índice de Gravidade de Doença , Calcificação Vascular/complicaçõesRESUMO
PURPOSE: A recent update in International Continence Society (ICS) terminology now recognizes nocturnal polyuria (NP) and diurnal polyuria (DP) as related subcategories of "Polyuria (global symptom)". This study determines the real-world clinical overlap between NP, DP, and 24-h polyuria (24hP) among men with nocturia. METHODS: Analysis of frequency-volume charts from men ≥ 18 years with ≥ 1 nocturnal void(s). Three separate analyses were performed using different rate criteria for NP, DP, and 24hP: (1) urine production > 90 mL/h (extrapolated from a proposed definition for NP); (2) > 125 mL/h (extrapolated from a proposed definition for 24hP [3000 mL/24 h]); and (3) > 1.67 mL/kg/h (extrapolated from the current ICS definition for 24hP [> 40 mL/kg/24 h]). Subjects were categorized as having one of five mathematically permissible phenotypic combinations: (1) isolated NP, (2) isolated DP, (3) NP + 24hP, (4) DP + 24hP, and (5) NP + DP + 24hP. RESULTS: 167, 95, and 61 patients were included at criteria 1, 2, and 3, respectively, with 56%, 43%, and 30% of patients demonstrating overlapping phenotypes (i.e., phenotypic combinations 3-5) at cut-offs 1-3, respectively. The prevalence of NP was similar across cut-offs (81-87%), but the prevalence of NP without 24hP was highly threshold-dependent (43-73%). CONCLUSION: Consistent with current ICS terminology, there exists a substantial overlap between NP, DP, and 24hP. As demonstrated in the current study, absolute volume-based criteria for NP/DP/24hP are indeed conducive to the diagnosis of concurrent NP + 24hP, and may be preferred over proportion-based NP criteria when both NP + 24hP are suspected.
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Noctúria/complicações , Noctúria/diagnóstico , Poliúria/complicações , Poliúria/diagnóstico , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Terminologia como Assunto , Fatores de TempoRESUMO
BACKGROUND: this study compares diuresis rate, sodium clearance and free water clearance (FWC) by age and time of day (nighttime vs. daytime) in subjects with and without nocturnal polyuria (NP) to determine whether these variables affect the phenotype of NP. METHODS: post hoc analysis of two prospective observational studies. Eight urine samples collected at 3-h intervals and a single blood sample were used to calculate daytime (10a/1p/4p/7p/10p) and nighttime (1a/4a/7a) diuresis rates, sodium clearance and FWC. Three mixed linear models were constructed for diuresis rate, sodium clearance and FWC using four predictor variables: NP status (present [nocturnal urine production >90 ml/h] vs. absent [≤90 ml/h]), time of day, age and study identification. RESULTS: subjects with NP experienced higher nighttime versus daytime diuresis rates, sodium clearance and FWC. Regardless of NP status, increased age was accompanied by an increase in the ratio of nighttime/daytime diuresis rate, nighttime sodium clearance and daytime sodium clearance. FWC showed a complex age effect, which was independent of time of day or NP status. CONCLUSIONS: age-related increases in nighttime/daytime diuresis rate, 24-h sodium clearance and 24-h FWC are not specific to subjects with NP. The age-related surge in either nocturnal sodium clearance or nocturnal FWC may represent the relevant substrate for behavioural or pharmacologic interventions targeting sodium diuresis or free water diuresis, respectively. Increases in FWC in older age groups may reflect impaired circadian rhythmicity of endogenous AVP or changes in responsiveness of the aged nephron to water clearance.
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Noctúria , Poliúria , Idoso , Diurese , Humanos , Noctúria/diagnóstico , Poliúria/diagnóstico , Sódio , ÁguaRESUMO
BACKGROUND: Haptoglobin (Hp) displays three major phenotypes (Hp 1-1, Hp 2-2 and Hp 2-1). Hp 1-1 has been implicated in high blood pressure and salt sensitivity, and thus may mediate excess urine production. AIM: To explore the relationship between Hp polymorphisms and polyuria (>40 mL/kg/24 hours). METHODOLOGY: Post hoc analysis of a prospective observational study of subjects who completed a renal function profile between October 2011 and February 2015 (n = 170). Hp phenotypes were determined by starch gel electrophoresis using haemoglobin-supplemented serum. The distribution of Hp phenotypes in subjects with and without polyuria was compared to a reference group of the same geography and ethnic composition. Diuresis rate, sodium clearance and free water clearance were compared within and between phenotypes. RESULTS: The Hp1 allele frequency was significantly overexpressed in subjects with polyuria compared to the reference group (0.500 vs 0.400, P < .05). Consistently, the Hp 1-1 phenotype was more prevalent in subjects with polyuria compared to the reference group (28% vs 16%, P < .05). In contrast to Hp 2-1/2-2, Hp 1-1 demonstrated no circadian variation in diuresis rate, sodium clearance or free water clearance. A significant association between plasma Hp concentration and 24-hours sodium clearance was observed in Hp 1-1 subjects without polyuria (ß = 0.222; 95% CI 0.003-0.441; P = .047). CONCLUSION: The Hp1 allele was more frequent in subjects with polyuria, and participants with the Hp 1-1 phenotype were at greater risk for polyuria. Hp 1-1 subjects demonstrated an altered ability to concentrate urine with a slower continuous excretion of sodium throughout the day. Plasma Hp concentration of Hp 1-1 was positively correlated with 24-hours sodium clearance in subjects without polyuria.