Improvement in International Prostate Symptom Score after prostatic urethral lifts is dependent on prostatic volume

INTRODUCTION

Prostatic urethral lifts (PUL) provide improvement in urinary symptoms for men with benign prostatic hyperplasia (BPH). The aim of this study is to determine operative factors associated with improvement in urinary symptoms after PUL in men with bothersome BPH.

MATERIALS AND METHODS

Men with BPH undergoing PUL at a single, tertiary center were identified from 2019 to 2022. Inclusion criteria included documented prostate volume as well as preoperative and postoperative cystoscopic images of the prostatic urethra. Multivariate regression modeling was performed to determine the predictive factors-including prostate volume, number of implants, and degree of unobstructed prostatic urethral channel-for improvement in International Prostate Symptom Score (IPSS) after PUL.

RESULTS

Of the 47 men, the distribution of prostate volume was 1 patient with < 30 grams, 33 patients with 30-79 grams, five patients with 80-100 grams, and six patients with > 100 grams. The mean number of implants used was six implants. The mean preoperative and postoperative IPSS were 23 and 14, respectively. The mean (standard error (SE)) change and percent change in IPSS score following PUL was 14 and 60%, respectively. The mean percent improvement in prostatic urethral channel after anterior clip placements was 67%. On multivariate analysis, larger prostate volume was associated with greater change in IPPS follow surgery (p = 0.0091) while number of implants and percent of prostatic urethral opening were not associated with change in IPSS (p = 0.3094 and p = 0.2249, respectively).

CONCLUSION

Men with larger prostates are associated with greater improvement in urinary symptom after PUL regardless of number of implants utilized and degree of prostatic urethral channel opening after prostatic implants.

Testicular Core Extraction: Important Technique for Determining Sperm Retrieval Method in Non-obstructive Azoospermia

OBJECTIVE

To assess the value of preliminary testicular core extraction (TCE) as a tool for determining whether to pursue clinic testicular extraction (cTESE) versus microscopic testicular sperm extraction (mTESE) to minimize both financial burden and procedural complexity.

METHODS

All men with non-obstructive azoospermia (NOA) from 2018 to 2022 who underwent clinic TCE were analyzed. Patients who were found to have sperm on initial TCE were recommended cTESE. Patients who did not have sperm on initial TCE were recommended for mTESE. Sensitivity, specificity, positive predictive value, and negative predictive value of TCE were calculated. Cost reductions were determined based on this institution's fees. A nonparametric Wilcoxon test was performed to determine statistical significance between the results of the TCE sperm present and sperm absent groups.

RESULTS

Of the 82 NOA patients undergoing TCE, 51 (62.2%) core biopsies were positive for sperm and 31 (37.8%) were negative for sperm. The SRR for 35 men who then underwent cTESE following sperm seen on TCE was 97.1%. The SRR for 8 men who underwent mTESE after no sperm was found on TCE was 75%. The positive predictive value of TCE for successful TESE result is 94.4% for men with NOA. Treatment success rate of TCE and cTESE was 79.1% with a cost reduction of 59.4%.

CONCLUSION

TCE is a prognostic tool to guide decision making between cTESE and mTESE and maximize sperm retrieval rate while mitigating financial burden and operative complexity. TCE is important to identify ideal candidates for both procedures to maximize efficacy and safety amongst men with NOA.

Peyronie's Disease: An Outcomes-Based Guide to Non-Surgical and Novel Treatment Modalities

The clinical landscape of Peyronie's disease is everchanging. There has been growing interest in non-invasive therapeutic options that could assist patients with achieving a meaningful reduction in penile curvature without surgical intervention. These therapies are wide-ranging in terms of their mechanisms of action, efficacies, and short- and long-term safety profiles. Recently, an abundance of outcomes literature on longstanding and novel non-surgical treatment modalities has been published. For sexual medicine providers hoping to offer patients the most up-to-date and evidence-based treatments for the management of Peyronie's disease, it can be challenging to gain a thorough understanding of this body of literature. In this clinical management review, the workup and current theories on the pathophysiology of Peyronie's disease are reviewed, and the most recent outcomes data on the currently available non-surgical treatment modalities are presented. With an accurate understanding of the current landscape of Peyronie's disease treatment, sexual health providers will be able to better evaluate and engage in evidence-based shared decision-making with their patients.

Joint consensus statement on the vaccination of adult and paediatric haematopoietic stem cell transplant recipients: Prepared on behalf of the British society of blood and marrow transplantation and cellular therapy (BSBMTCT), the Children's cancer and Leukaemia Group (CCLG), and British Infection Association (BIA)

Haematopoietic stem cell transplant (HSCT) recipients have deficiencies in their adaptive immunity against vaccine preventable diseases. National and International guidance recommends that HSCT recipients are considered 'never vaccinated' and offered a comprehensive course of revaccination. This position statement aims to draw upon the current evidence base and existing guidelines, and align this with national vaccine availability and licensing considerations in order to recommend a pragmatic and standardised re-vaccination schedule for adult and paediatric HSCT recipients in the UK.

Association of Residents' Medical School Reputation and Urology Residency Program Ranking

INTRODUCTION

The Urology Residency Match process is a highly competitive application process that evaluates coursework performance, standardized examination scores, research productivity, quality of letter of recommendations, and participation in away rotations. With recent changes to medical school grading metrics, lack of in-person interviews, and examination scorings, less objective metrics are available to stratify applicants. We characterized the association of urology residents' medical school and urology residency program rankings.

METHODS

Using publicly available resources, all urology residents from 2016 to 2022 were identified. Their medical school and urology residency rankings were determined from 2022 US News and World Reports and Doximity urology residency reputation. Ordinal logistic regression modeling was used to determine the association between medical school and residency rankings.

RESULTS

A total of 2,306 successfully matched residents were identified from 2016 to 2022. There was positive association between urology program and medical school ranking (P < .001). Within each urology program tier over the last 7 years, there was no significant change over time in the proportions of urology residents by medical school rankings (P >0.05). A consistent proportion of matched residents from higher ranked medical schools matched into top ranked urology programs, while a consistent proportion of applicants from lower ranked medical schools matched into lower ranked urology programs across each application cycle from 2016 to 2022 (P < .05).

CONCLUSIONS

We observed that over the last 7 years trainees from higher ranked medical schools were more commonly represented in top urology programs while lower ranked urology programs were overrepresented by residents from lower ranked medical schools.

Is urgent surgical management necessary for priapism in pediatric patients with hematologic conditions?

INTRODUCTION

Acute priapism is usually considered a medical emergency that warrants prompt urologic evaluation and treatment. Efforts have been made to determine the optimal management strategy for pediatric priapism.

OBJECTIVE

The aim of this study is to assess differences in conservative, minimally-invasive, and operative management of acute priapism in the pediatric population.

STUDY DESIGN

A retrospective study of pediatric patients with acute priapism from 2015 to 2021 at a single tertiary care children's hospital was conducted. Conservative, minimally-invasive, and operative approaches for the priapism episodes during these hospital encounters were analyzed.

RESULTS

Thirty-nine patients were identified with a total of 61 cases of acute pediatric priapism were evaluated in the study period. Eight-three percent of patients were African-Americans, and 72% of patients had a history of sickle cell disease. Oxygen therapy (P = 0.001) and hydration with intravenous fluids (P = 0.00318) were more commonly utilized for hematologic-associated cases compared to other etiologies. For priapism episodes of hematologic etiology, 18 (40.0%) and 18 (40.0%) patients received phenylephrine injection and aspiration/irrigation (e.g., minimally-invasive therapy), respectively, while for the other causes of priapism, three (18.8%) and four (25.0%) received phenylephrine injection and aspiration/irrigation (e.g., minimally-invasive), respectively. Conservative and minimally-invasive treatment resulted in complete resolution of priapism in 27 (60%) and 16 (35.5%) patients with hematologic-associated priapism while 12 (75%) and 1 (6.3%) patients with other etiologies had resolution of priapism with conservative and minimally-invasive treatment, respectively. One patient received shunting in the hematologic group while two patients received shunting in the non-hematologic group (P = 0.1031).

DISCUSSION

Hematologic disorders are the most common causes of priapism in children and adolescents. An overwhelming majority of priapism events in the pediatric population can be managed with conservative therapies including oxygenation and intravenous hydration as well as minimally-invasive procedures such as corporal aspiration, irrigation and/or injections. The utilization of corporal shunting, anesthesia, and hospital resources is infrequently necessary for pediatric priapism episodes.

CONCLUSION

While urgent surgical management is often performed in the adult population, a minimally-invasive management strategy can be implemented in the pediatric population where an extended period of conservative management that avoids operative management and general anesthesia is effective.

Management of Mammalian Bites to the External Genitalia: A Scoping Review

OBJECTIVE

To review the existing publications in literature in order to determine the approaches for the medical and operative management of mammalian bites to the external genitalia.

METHODS AND MATERIAL

The Preferred Reporting Items for Systematic Reviews and Meta-Analysis for Scoping Review guidelines were followed. Four databases were searched. Articles were independently screened and analyzed by two reviewers. Publications were included if detailed summaries of genitalia bites and management were documented. Discrepancies were resolved by a third reviewer. Data was extracted from the final article cohort.

RESULTS

Forty-two articles were included in this scoping review. A total of 67 cases of mammalian bites to the genitalia were reported in the cohort. The most common injury site was the penis (44.9%). Dog and human bites were the most common type of mammalian bites (61.2% and 26.9%, respectively). 13.4% of cases were managed with medical therapy while 86.6% of cases required surgical intervention. The most common intervention was wound irrigation, debridement, and primary closure (32.8%). Though uncommon, other operative approaches included skin flaps (7.5%) and grafts (4.5%), re-implantation (4.5%), urethroplasty/repair (7.5%), penectomy (3.0%), scrotoplasty (3.0%), and perineal urethrostomy (1.5%). The reported complication rate was 19.4%. The mean follow-up time was 39.9 months.

CONCLUSION

Trauma related to mammalian bites is associated with high utilization of healthcare resources and cost. Though management of such bites to the genitalia is controversial, surgical intervention is often warranted ranging from simple debridement of devitalized tissue to complex reconstructive surgery. This review underscores the need for further investigation of mammalian bites to the genitalia to improve surgical options and monitor for long-term complication rates.

Demographic and Socioeconomic Factors Associated with Urinary Stone Disease Management in a Large Urban US Population

OBJECTIVE

To determine the influence of socioeconomic parameters on urinary stone surgeries.

METHODS

A retrospective cohort study analyzed patients undergoing urolithiasis surgery in our community network hospital in North Carolina from 2005-2018.

RESULTS

Of 7731 patients, 2160 (28%), 5,174 (67%), and 397 (5%) underwent SWL, URS, and PCNL, respectively. A higher proportion of Whites underwent URS (67%) and SWL (74%) than PCNL (56%); whereas a larger percentage of Blacks underwent PCNL (24%) than URS (20%) and SWL (15%) groups (P <.001). Private insurance payers were greater in the SWL (95%) group than URS (80%) and PCNL (81%) (P <.001). The distribution of median income was significantly different amongst the 3 surgeries with higher income classes overutilizing SWL and underutilizing PCNL compared to lower income classes (P <.001). In linear regression modeling, the proportion of SWL in a postal code was positively associated with median income (R²=0.55, P <.001); URS and PCNL were negatively associated with median income (R²=0.40, P <.001 and R²=0.41, P <.001, respectively). On multivariate logistic regression modeling, Blacks were significantly more likely to undergo PCNL than Whites (aOR 1.32, 95% CI 1.01-1.74 P <.050). Private insurance payers were more likely to undergo SWL (aOR 11.0, 95% CI 7.26-16.8, P <.0001) than public insurance payers. Patients in higher median income brackets are significantly less likely to undergo PCNL than those in the <$40,000 income bracket (P <.0001).

CONCLUSION

Our study suggests that socioeconomic status impacts urolithiasis surgical management, underscoring disparity recognition importance in endourologic care and ensuring appropriate surgical care regardless of socioeconomic status.

Epidemiology and survival outcome of adult kidney, bladder, and prostate rhabdomyosarcoma: A SEER database analysis

Rhabdomyosarcoma (RMS) is rare in adulthood, accounting for 2%-5% of adult soft tissue tumors, and less than 20% occur in genitourinary organs. Given its rarity, survival data on adult kidney, bladder, and prostate RMSs is limited. In this population-based analysis, we performed an analysis of all adult RMS cases reported in Surveillance, Epidemiology, and End Results (SEER) database to understand prognostic factors among kidney, bladder, and prostate RMS. A query of the SEER database was performed from 1973 to 2016 for patients >18 of age with RMS. The final cohort consisted of 14 kidney, 35 bladder, and 21 prostate RMS cases in the adult population. Demographic, treatment, and survival data were obtained. Analysis was performed using Fisher's exact test, survival analysis, and model. The median (range) age of diagnosis for adult bladder RMS was 65 years old (19-84) compared to 52.5 (28-68) and 42 (19-87) for kidney and prostate (p = 0.007). About 78.6% of patients underwent surgical intervention. Five-year overall survival (OS) for adult kidney, bladder, and prostate RMS are 17.1% (2.9-41.6%), 22.2% (9.4-38.4%), and 33.0 (12.8-55.0%), respectively. OS was not statistically associated with primary site (p = 0.209). On multivariable analysis, compared to adult bladder RMS, kidney RMS had a higher incidence of mortality (HR: 2.16, 95% CI 1.03-4.53, p = 0.041). Incidence of mortality from prostate RMS was not significantly different from bladder RMS (HR: 0.70, 95% CI 0.30-1.65, p = 0.411). Extent of disease (HR: 5.17, 95% CI 2.09-12.79, p < 0.001) and older age (HR 1.03, 95% CI 1.01-1.04, p = 0.002) were adverse prognostic factors for OS. Overall survival at 5 years for adult kidney, bladder, and prostate RMS is poor. Localized disease and younger age are prognostic factors for improved outcomes in adult RMS. Hence, early diagnosis and intervention appear paramount to improved survival for this rare malignancy in adulthood.

1097 Sleep Disturbances, Sleep Burden, And Depressive Symptoms In US Hispanics/Latinos: Results From The HCHS/SOL Sueño Study

Introduction

While sleep disturbances and depression often co-occur, these associations are understudied among Hispanics/Latinos. We examined the associations of sleep disturbances and sleep burden with depressive symptoms among Hispanic/Latino adults in the United States.

Methods

We used cross-sectional data from the Hispanic Community Health Study/Study of Latinos Sueño Ancillary study (2010-2013). The study enrolled 2072 adults (ages 18-64; 51.5% females) who completed one-week wrist-actigraphy and sleep questionnaires. Sleep burden was operationalized as the total count of sleep disturbances across six domains (duration, efficiency, midpoint, variability, insomnia, sleepiness). Depressive symptoms were assessed using the Center for Epidemiological Studies Depression scale (CESD-10). We used weighted survey linear regressions to evaluate the association of sleep disturbances and sleep burden with elevated depressive symptoms (CESD≥10) in individual models adjusted for age, gender, site, heritage, nativity, education, income, and employment. Sensitivity analyses further adjusted for behavioral health risk factors and apnea-hypopnea index.

Results

An estimated 28.3% had elevated depressive symptoms, 8.0% had short sleep duration (&lt;6 hours of sleep), 10.9% had long sleep duration (&gt;9 hours), 45.2% exhibited a later sleep midpoint (≥4:00AM), 38.4% had high sleep timing variability (upper third tertile for between day sleep midpoint), 15.3% had insomnia (ISI≥10), 17.3% had excessive daytime sleepiness (ESS ≥10), 21.5% had poor sleep efficiency (&lt;85%), and 77.4% had a total sleep burden count of ≥0. Insomnia (ß=0.49,95%CI:.43,.56), later sleep timing (ß=0.10,95%CI:.04,.16), excessive daytime sleepiness (ß=0.19,95%CI:.11,.27), poor sleep efficiency (ß=0.09,95%CI:.02,.17), high variability (ß=0.07, 95%CI:.01,.12), and sleep burden (ß=0.11,95%CI:.09,.13), were each positively associated with elevated depressive symptoms in individual adjusted models and sensitivity analyses. Extreme sleep durations were not associated with elevated depressive symptoms.

Conclusion

Multiple inter-related sleep disturbances, particularly those pertaining to sleep quality and timing, are associated with depression and may be targets for future interventions aimed at improving mood among Hispanics/Latinos.

Support

HL127307, HL098927, HL125748

0357 CPAP Adherence is Lower in Minority Neighborhoods

Introduction

The effectiveness of continuous positive airway pressure (CPAP) in treating obstructive sleep apnea (OSA) is limited by adherence. Small, single-center studies have reported CPAP adherence is lower in racial minorities suggesting disparities in OSA care. We used nationally representative data to assess racial differences in CPAP adherence at a neighborhood level.

Methods

Telemonitoring data were obtained from a therapy database maintained by a CPAP manufacturer. Usage over the first 90 days in patients initiated on CPAP between 11/01/2015 and 10/31/2018 who had at least one usage session, age 18-90 years, and valid U.S. zip code were mapped to a zip code tabulation area (ZCTA). Age- and sex-adjusted CPAP usage was calculated for each ZCTA with greater than 10 CPAP users. Ecologic analyses were performed to model the association of the proportion of blacks and Hispanics in each ZCTA (obtained from the 2013-2017 American Community Survey) on CPAP usage controlling for proportion of adults with bachelor’s degree and proportion of adults with household income below the poverty line.

Results

Our analysis included 13,118 ZCTAs averaging data over 737,274 patients. In adjusted analyses, each 10% increase in the proportion of blacks and Hispanics was associated with a 0.12 (95% CI 0.11-0.12) hour and 0.14 (95% CI 0.14-0.15) hour decrease in nightly CPAP use, respectively. Mean usage in ZCTAs with &lt;1%, 1-2.5%, 2.5-10%, 10-25%, and 25-100% blacks were 4.96, 4.81, 4.67, 4.56, and 4.14 hours respectively (p&lt;0.001). Mean usage in ZCTAs with &lt;1%, 1-2.5%, 2.5-10%, 10-25%, and 25-100% Hispanics were 4.87, 4.86, 4.75, 4.50, and 4.10 hours respectively (p&lt;0.001).

Conclusion

CPAP adherence is lower in neighborhoods with higher proportions of black and Hispanic residents independent of differences in education or poverty. These differences lead to lower likelihood of meeting insurance coverage requirements for CPAP therapy, potentially exacerbating sleep health disparities.

Support

Philips Respironics, NIH R25HL130600 and K24HL127307.

0402 Impact of Various Actigraphic Editing Approaches on Sleep/Wake Outputs in Adults with Insomnia and Healthy Sleepers

Introduction

Actigraphy data can be edited using a variety of approaches. However, whether time-intensive manual editing provides different sleep/wake estimates compared to other approaches is unknown. The purpose of this study was to compare sleep/wake data obtained from a standardized editing approach that incorporates multiple inputs versus three other common approaches.

Methods

72 adults (33.8±11.1 y, 74% female, 71% white) provided 1022 nights of data for analysis; 45 were healthy sleepers (678 nights) and 27 met DSM-5 criteria for insomnia. Participants wore an Actiwatch Spectrum on their nondominant wrist and completed a sleep diary for 3-24 nights. Each night’s rest interval was set using four different approaches: (1) a standardized process based upon published guidelines (Patel et al., Sleep 2015) that incorporates a hierarchical order of multiple inputs (event marker, light, diary, activity; STANDARD); (2) software-provided automated algorithm (AUTO); (3) automated algorithm with incorporation of event markers (AUTOE); and (4) sleep diary (DIARY). We used linear mixed-effects models to evaluate whether sleep/wake parameters differed between the STANDARD and other editing approaches, accounting for patient status (healthy sleeper, insomnia) and the possibility that differences among editing approaches may be dependent on patient status.

Results

All results are expressed relative to the STANDARD approach. Bedtime was 36.1±5.1 min earlier (P&lt;.0001) and morning out-of-bed time was 13.6±5.7 min later (P=.02) using the AUTO (P&lt;.0001) approach. Time in bed was 42.3±4.7 min longer with AUTO (P&lt;.0001). Sleep onset latency was 11.7±1.4 min and 2.8±1.4 min longer for AUTO (P&lt;.0001) and DIARY (P=.05), respectively. Sleep duration was 22.5±4.4 min longer with AUTO (P&lt;.0001). Wake after sleep onset was 6.8±1.2 min greater with AUTO (P&lt;.0001). Similar patterns were observed for all sleep/wake measures among healthy sleepers and adults with insomnia.

Conclusion

A standardized approach to editing actigraphy data leads to different sleep/wake estimates compared to other common approaches, though the differences were often small in magnitude and not dependent upon sleep status. Most notably, reliance upon the automated algorithm yielded longer time in bed, sleep duration, sleep onset latency, and wake after sleep onset compared to the standardized approach.

Support

NIH K23HL118318

0677 Patient Preferences On Initiating Treatment With Continuous Positive Airway Pressure

Introduction

Clinical guidelines recommend continuous positive airway pressure (CPAP) therapy be initiated in patients with obstructive sleep apnea (OSA) either at home using an auto-titrating device or following manual titration in the sleep laboratory. Patient preference between these two options is unknown.

Methods

Patients newly prescribed CPAP therapy for the treatment of OSA at an academic sleep medicine clinic were surveyed by telephone within one month of initiating treatment. Data on demographics, disease severity and CPAP adherence were obtained from the medical record.

Results

A total of 75 participants (56% male, mean age 52±15 yrs, 48% moderate to severe OSA) were surveyed. Physicians prescribed home initiation of CPAP in 51%, lab initiation in 23%, and allowed the patient to choose in 27% of cases. Overall, 67% of participants (95% CI [56%-77%]) reported preference for home initiation. Preference for home initiation did not vary by age, sex, AHI, degree of sleepiness, or type of diagnostic study (home vs. lab sleep study) performed (p&gt;0.10 for all). Convenience (44%) and starting treatment faster (44%) were the most common reasons provided for those favoring home initiation, while sleep technician availability (40%), optimization of pressure settings (32%), and ability to try multiple masks (28%) were cited by those favoring lab initiation. The prevalence of CPAP adherence at 90 days tended to be higher in those whose treatment was initiated aligned to preference (79% in those whose treatment initiation was concordant with preference vs. 64% in those whose treatment initiation was discordant, p=0.16).

Conclusion

Overall, two-thirds of patients with OSA prefer initiation of CPAP be done at home. This preference does not vary by demographics, OSA severity or diagnostic modality. Initiating treatment concordant with patient preference may lead to greater adherence.

Support

American Thoracic Society Academic Sleep Pulmonary Integrated Research/Clinical (ASPIRE) Fellowship, K24 HL127307

1144 Actigraphy-defined Sleep And Neurocognitive Decline In Middle-age Hispanic/Latino Adults

Introduction

Few studies have evaluated objective sleep measures and longitudinal neurocognitive decline, particularly in middle-age or Hispanic/Latino adults. We evaluated prospective associations between actigraphy-defined sleep and 7-year neurocognitive change among Hispanic/Latino adults. We hypothesized that sleep duration would be associated with neurocognitive decline.

Methods

We analyzed data from 1,036 adults 45-64 years of age from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), a multi-center prospective cohort study of diverse community-dwelling Hispanic/Latino adults. At Visit 1 (2008-2011), participants underwent neurocognitive assessments, 7-days of actigraphy, home sleep testing, and sleep questionnaires (including the Insomnia Severity Index). Seven years later, participants repeated neurocognitive assessments. The neurocognitive battery included the Six-Item Screener, Brief Spanish-English Verbal Learning Test, phonemic word fluency test, and Digit Symbol Subtest. Survey linear regression was used to evaluate prospective associations between actigraphy-defined or self-reported sleep variables and neurocognitive change. Final models adjusted for objectively-defined variables (age, body-mass index, Field Center, and time between neurocognitive assessments), and self-reported variables (sex, education, Hispanic/Latino background, alcohol consumption, physical activity, heart failure, cerebrovascular events, depression and anxiety symptoms, and antidepressant use).

Results

At Visit 1, the sample was 55% female and mean age was 54.9±2.2 years. The mean sleep duration was 402.6±27.6 minutes, mean sleep-onset latency was 11.3±9.7 minutes, mean number of days with naps of ≥ 15 minutes duration was 1.1±0.7, and mean sleep-time per nap was 51±14.1 minutes. Increased sleep-onset latency was associated with 7-year declines in global neurocognitive function (β=-0.0026, p&lt;0.01), verbal learning (β=-0.0028, p&lt;0.001) and verbal memory (β=-0.036, p&lt;0.05). Increased sleep-time per nap predicted better verbal memory (β=0.0038, p&lt;0.05). In contrast, sleep duration, sleep fragmentation, and self-reported sleep measures were not associated with neurocognitive change.

Conclusion

Among middle-age adults, sleep-onset latency and nap duration were associated with neurocognitive change. These findings may serve as targets for intervention of neurocognitive decline.

Support

This work is supported by the National Institute on Aging: R01AG048642, RF1AG054548, R01AG061022, R21AG056952, and R21HL140437 (AR).

0609 Sleep Phenotypes in Middle-Aged and Older Hispanics/Latinos. Results from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL)

Introduction

Identifying sleep phenotypes in the diverse and understudied US Hispanic/Latino population is critical to developing interventions and mitigating distal clinical outcomes (e.g. dementias).

Methods

Using latent class analyses (LCA), we identify empirically derived and clinically meaningful sleep phenotypes using data on community dwelling middle-aged/older adults (ages ≥45-years) from the HCHS/SOL (2008-2011) - Investigation of Neurocognitive Aging (n=6,377). Sleep variables used included Apnea/Hypopnea Index (AHI), percent time SpO2&lt;90%, Epworth Sleepiness Scale (ESS), Women’s Health Initiative Insomnia Rating Scale (WHIIRS), self-reported average sleep duration, restless legs symptoms, napping frequency, and sleep quality.

Results

Mean (M) age was 56.4±8.1 years, and 54.7% were female. Average AHI, ESS, WHIIRS, and sleep duration were 8.7±13.1, 6.0±5.0, 7.6±5.5, and 7.8±1.4, respectively, and 25.8% had zero percent time SpO2 &lt;90%. Fit statistics indicated that a four-class solution provided the best data fit. The derived classes, adjusting for age, sex, income, and acculturation, corresponded with four clinically meaningful groups: (1) 28.8% were asymptomatic [(M) AHI=0.8; (M) ESS=5.6; (M)WHIIRS=7.6; (M) sleep duration=7.8; 0% SpO2&lt;90%=74.1%], (2) 25.7 % were asymptomatic mild sleep apnea [(M) AHI=6.2; (M) ESS=3.8; (M) WHIIRS=2.9; (M) sleep duration=7.8; 0% SpO2&lt;90%=8.8%], (3) 19.4% were symptomatic sleep apnea [(M) AHI=25.6; (M) ESS=8.5; (M) WHIIRS=7.2; (M) sleep duration=7.7; 0% SpO2&lt;90%= 0.5%], and (4) 26.1% were insomnia [(M) AHI=5.7; (M) ESS=6.7; (M) WHIIRS=13.0; (M) sleep duration=7.8; 0% SpO2&lt;90%=10.3%]. Classification into groups 3 and 4 were primarily driven by elevated AHI and WHIIRS scores, respectively. The distribution of scores in the derived groups suggest variations relative to current clinical thresholds.

Conclusion

We identified 4-groups using LCA in a community-based sample of diverse U.S. Hispanic/Latino adults. Better characterization of sleep phenotypes for Hispanics/Latinos can help in developing targeted interventions studies and ameliorate health disparities.

Support

5R01AG048642-05; R21AG056952; R21HL140437.

0607 Clinical Phenotypes of OSA in Diverse Hispanics/Latinos: Results from the Hispanic Community Health Study/Study of Latinos

Introduction

Recent work on US non-Latino Whites and Europeans from clinical samples used obstructive sleep apnea (OSA) symptoms to generate OSA phenotypes for individuals with moderate-severe OSA and proposed between 3-5 clusters. Validating these clusters in a diverse Hispanic/Latino community-based population with different biopsychosocial characteristics is crucial for early OSA identification and more personalized treatment.

Methods

This work is based on baseline data from The Hispanic Community Health Study/Study of Latinos (HCHS/SOL). HCHS/SOL is a prospective cohort study designed using a multisite (Bronx, NY, Chicago, IL, Miami, FL, San Diego, CA) multistage probability sample. The subpopulation of interest included adults 18-74 years (unweighted n=1,623) meeting criteria for moderate-severe OSA symptoms (≥15 Apnea-Hypopnea index (AHI) events per hour). We performed latent class analysis (LCA) using 15 common OSA symptoms to identify phenotype clusters.

Results

Average age was 52.4 ± 13.9 years and 34.1% were female. Mean AHI was 33.8 ± 22.5 events per hour. Fit statistics and clinical significance suggested that a three-class solution provided best fit to the data. The symptom profiles were consistent with (1) a Minimally Symptomatic group (46.8%), (2) a Disturbed Sleep group (38.1%), and (3) a Daytime Sleepiness group (15.1%). Validation analyses using alternative hierarchical and partitioning algorithms also suggested support for a three-class solution.

Conclusion

Sleep apnea phenotypes among diverse Hispanics/Latinos were consistent with recent findings from the Sleep Apnea Global Interdisciplinary Consortium. However, we found notable differences in the prevalence of these clusters relative to Whites. This suggests that other biopsychosocial factors may be contributing to OSA phenotypes among Hispanics/Latinos. Identification of OSA phenotypes in Hispanics/Latinos could inform better sleep interventions and therapeutics and help better align public health resources.

Support

5R01AG048642-05; R21AG056952; R21HL140437.

Incidental finding of bilateral renal and adrenal anastomosing hemangiomas: A rare case report

Anastomosing hemangiomas are rare variants of vascular tumors found in adrenal, hepatic, and gastrointestinal tissue. Frequently, renal anastomosing hemangiomas are misdiagnosed on computed tomography (CT) as kidney cancers, resulting in unnecessary workups and detrimental treatments. We present a rare case of bilateral renal and adrenal anastomosing hemangioma found incidentally on renal biopsy. Patient is a 39 year-old African American male on hemodialysis with a history of end-stage renal disease secondary to lupus who presented with acute pericarditis and worsening renal insufficiency.

Mid-cervical interneuron networks following high cervical spinal cord injury

Spinal interneuron (IN) networks can facilitate respiratory motor recovery after spinal cord injury (SCI). We hypothesized that excitatory synaptic connectivity between INs located immediately caudal to unilateral cervical SCI would be most prevalent in a contra- to ipsilateral direction. Adult rats were studied following chronic C2 spinal cord hemisection (C2Hx) injury. Rats were anesthetized and ventilated and a multi-electrode array was used to simultaneously record INs on both sides of the C4-5 spinal cord. The temporal firing relationship between IN pairs was evaluated using cross-correlation with directionality of synaptic connections inferred based on electrode location. During baseline recordings, the majority of detectable excitatory IN connections occurred in a contra- to- ipsilateral direction. However, acute respiratory stimulation with hypoxia abolished this directionality, while simultaneously increasing the detectable inhibitory connections within the ipsilateral cord. We conclude that propriospinal networks caudal to SCI can display a contralateral-to-ipsilateral directionality of synaptic connections and that these connections are modulated by acute exposure to hypoxia.

Oral tongue carcinoma among young patients: An analysis of risk factors and survival

INTRODUCTION

The incidence of oral tongue squamous cell carcinoma (OTSCC) in younger adults has rapidly increased over the past two decades. While tobacco and alcohol use may be less likely to cause these tumors, it remains controversial whether differences also exist in their prognosis. Our aim is to examine the risk factors for cancer among young (<45 years old) OTSCC patients at our institution, and to compare their recurrence and survival with older patients in a matched cohort.

MATERIALS AND METHODS

All OTSCC patients seen at our institution between 2000 and 2015 were reviewed. Patients under 45 who with sufficient treatment information were matched 1:1 on race, T-stage, and N-stage with patients 45 and older. Three-year recurrence and survival were determined in stratified and adjusted Cox regression models.

RESULTS

Of 397 OTSCC patients were seen at our institution, 117 (29%) were less than 45 years old. Younger patients were significantly more likely to be female, (50% vs. 39%; p = 0.04) and to abstain from tobacco (51% vs. 39%; p < 0.01). Young patients in the matched cohort were significantly more likely to have a recurrence (HR 3.9 95% CI 1.4-10.5). There was no difference in overall survival.

CONCLUSION

Younger OTSCC patients in a matched cohort were more likely to recur within 3 years, although there was no difference in overall mortality. Differences in risk factors and recurrence between older and younger patients suggest that some cancer among younger patients may be distinct from traditional OTSCC.

Coupling multielectrode array recordings with silver labeling of recording sites to study cervical spinal network connectivity

Midcervical spinal interneurons form a complex and diffuse network and may be involved in modulating phrenic motor output. The intent of the current work was to enable a better understanding of midcervical "network-level" connectivity by pairing the neurophysiological multielectrode array (MEA) data with histological verification of the recording locations. We first developed a method to deliver 100-nA currents to electroplate silver onto and subsequently deposit silver from electrode tips after obtaining midcervical (C3-C5) recordings using an MEA in anesthetized and ventilated adult rats. Spinal tissue was then fixed, harvested, and histologically processed to "develop" the deposited silver. Histological studies verified that the silver deposition method discretely labeled (50-μm resolution) spinal recording locations between laminae IV and X in cervical segments C3-C5. Using correlative techniques, we next tested the hypothesis that midcervical neuronal discharge patterns are temporally linked. Cross-correlation histograms produced few positive peaks (5.3%) in the range of 0-0.4 ms, but 21.4% of neuronal pairs had correlogram peaks with a lag of ≥0.6 ms. These results are consistent with synchronous discharge involving mono- and polysynaptic connections among midcervical neurons. We conclude that there is a high degree of synaptic connectivity in the midcervical spinal cord and that the silver-labeling method can reliably mark metal electrode recording sites and "map" interneuron populations, thereby providing a low-cost and effective tool for use in MEA experiments. We suggest that this method will be useful for further exploration of midcervical network connectivity.NEW & NOTEWORTHY We describe a method that reliably identifies the locations of multielectrode array (MEA) recording sites while preserving the surrounding tissue for immunohistochemistry. To our knowledge, this is the first cost-effective method to identify the anatomic locations of neuronal ensembles recorded with a MEA during acute preparations without the requirement of specialized array electrodes. In addition, evaluation of activity recorded from silver-labeled sites revealed a previously unappreciated degree of connectivity between midcervical interneurons.

The effect of hypercapnia on the sensitivity to flicker defined stimuli

BACKGROUND/AIMS

To investigate the effect of increased CO2 levels on flicker defined stimuli.

METHODS

The sensitivity of two flicker defined tasks was measured in nine healthy, trained observers using the Flicker Defined Form (FDF) stimulus of the Heidelberg Edge Perimeter (HEP; Heidelberg Engineering) and Frequency Doubling Technology (FDT) stimulus of the Matrix perimeter (Carl Zeiss Meditec) during normoxia and 15% hypercapnia (end-tidal CO2 increased by 15% relative to baseline). HEP-FDF and Matrix-FDT sensitivities were analysed for the global field, superior and inferior hemifields and at specific matched eccentricities, using repeated measures analysis of variance. The main effect of hypercapnia on flicker sensitivity was analysed using regression models.

RESULTS

Higher flicker sensitivity outcomes with increasing CO2 values were found for HEP-FDF and Matrix-FDT with a statistically significant main effect for HEP-FDF global, superior and inferior hemifields (p<0.01 for all) as well as 6°, 18°, 12° and 24° eccentricities (p=0.03, 0.04, 0.01, 0.05, respectively). When comparing mean sensitivity values between normocapnia and hypercapnia conditions, no statistically significantly different results were found for HEP-FDF and Matrix-FDT (p>0.05).

CONCLUSIONS

As CO2 levels were increased in healthy young individuals, there was an associated increase in visual sensitivity that was only significant for HEP-FDF stimuli, highlighting the different mechanisms involved in processing each of HEP-FDF and Matrix-FDT stimuli. Mean visual sensitivity outcomes were found to be similar for normocapnia and hypercapnia suggesting that a capability to compensate for a mild and stable increase in systemic CO2 levels may exist.

Helicobacter pylori downregulates expression of human β-defensin 1 in the gastric mucosa in a type IV secretion-dependent fashion

Helicobacter pylori establishes a chronic lifelong infection in the human gastric mucosa, which may lead to peptic ulcer disease or gastric adenocarcinoma. The human beta-defensins (hβDs) are antimicrobial peptides, hβD1 being constitutively expressed in the human stomach. We hypothesized that H. pylori may persist, in part, by downregulating gastric hβD1 expression. We measured hβD1 and hβD2 expression in vivo in relation to the presence, density and severity of H. pylori infection, investigated differential effects of H. pylori virulence factors, and studied underlying signalling mechanisms in vitro. Significantly lower hβD1 and higher hβD2 mRNA and protein concentrations were present in gastric biopsies from infected patients. Those patients with higher-level bacterial colonization and inflammation had significantly lower hβD1 expression, but there were no differences in hβD2. H. pylori infection of human gastric epithelial cell lines also downregulated hβD1. Using wild-type strains and isogenic mutants, we showed that a functionalcag pathogenicity island-encoded type IV secretion system induced this downregulation. Treatment with chemical inhibitors or siRNA revealed that H. pylori usurped NF-κB signalling to modulate hβD1 expression. These data indicate that H. pylori downregulates hβD1 expression via NF-κB signalling, and suggest that this may promote bacterial survival and persistence in the gastric niche.

Comparative efficacy of two standard methods for determination of iron and zinc in fruits, pulses and cereals

Micronutrients are essential elements needed in small amounts for adequate human nutrition and include the elements iron and zinc. Both of these minerals are essential to human well-being and an adequate supply of iron and zinc help to prevent iron deficiency anaemia and zinc deficiency, two prevalent health concerns of the developing world. The levels of zinc and, iron were measured in the Banana, Papaya, Rice, Finger millet, Soybean and Urdbean. Standard Atomic absorption spectroscopy (AAS) method was also applied to all the samples for zinc and iron analysis and compared with inductively coupled plasma mass spectroscopy (ICP-MS). It was observed that there was no matrix interference affecting the determination of both elements interested in all the samples analyzed. Average concentration relative standard deviation and standard deviation were used for the statistical evaluation of the results for both elements. Correlation coefficient was used as statistical model to compare both the techniques.

Phase II Study of Paclitaxel in Patients With Soft Tissue Sarcomas

Purpose. Patients with soft tissue sarcoma (STS) who have previously received standard chemotherapy including adriamycin (doxorubicin), ifosfamide, cyclophosphamide and DTIC (dacarbazine) have very limited therapeutic options. It is important to identify new drugs with some activity in this disease and we therefore undertook this trial to determine the antitumor activity of paclitaxel (Taxol).Methods. We conducted a phase II study of paclitaxel in patients with STS who had received prior standard chemotherapy. Paclitaxel was administered at a starting dose of 200 mg m(-2) as a 24-h infusion with STS premedication, every 21 days or upon hematologic recovery (absolute granulocyte count (AGC) >/= 1500/mul, platelets >/= 100 000/mul). Neupogen was not used routinely. The study was conducted based on a two-stage design proposed by Simon. Responses were assessed radiographically using standard criteria.Results. Nineteen eligible patients were treated in the first stage of the study. The median age was 50 years (range 20-68 years), and there were nine females and 10 males with Zubrod performance status of 1 or 2. One patient achieved a minor response. Median AGC nadir was 0.1/mul on day 12 with absolute neutropenia lasting 5 days. Median platelet nadir was 171 000/mul on day 9. There were no grade 3/4 non-hematologic toxicities and no deaths related to treatment.Discussion. Paclitaxel, at this dose and schedule, is well tolerated but inactive in this patient population.

Identification of patient safety improvement targets in successful vascular and endovascular procedures: analysis of 251 hours of complex arterial surgery

OBJECTIVES

To investigate failures in patient safety for patients undergoing vascular and endovascular procedures to guide future quality and safety interventions.

DESIGN

Single centre prospective observational study.

METHODS

66 procedures (17 thoracoabdominal and 23 abdominal aortic aneurysms, 4 carotid and 22 limb procedures) were observed prospectively over a 9-month period (251 h operating time) by two trained observers. Event logs were recorded for each procedure. Two blinded experts identified and independently categorised failures into 22 types (using a validated category tool) and severity (5-point scale). Data are expressed as median (range). Statistical analysis was performed using Mann-Whitney U, Kruskal-Wallis and Spearman's Rank tests.

RESULTS

1145 failures were identified with good inter-assessor reliability (Cronbach's alpha 0.844). The commonest failure types related to equipment (including unavailability, configuration and other failures) (269/1145 [23.5%]) and communication (240/1145 [21.0%]). A comparatively lower number of technical and psychomotor failures were identified (103 [9.0%]). The number of failures correlated with procedure duration (rho = 0.695, p < 0.001) but not anatomical site of the procedure or pathology of the disease process. Failure rate was higher in patients undergoing combined surgical/endovascular procedures compared to open surgery (median 5.7/h [IQR 4.2-8.1] vs 3.0/h [2.5-3.5]; p < 0.001). The severity of failures was similar (1.5/5 [1-2] vs 1/5 [1-2] respectively; p = 0.095). For combined procedures, failure rates were significantly higher during the endovascular phase (9.6/h [7.5-13.7]) compared to the non-endovascular phase (3.0/h [1.0-5.0]; p < 0.001).

CONCLUSIONS

Failures in patient safety are common during complex arterial procedures. Few failures were severe, although minor failures during critical stages and accumulation of multiple minor failures may potentially be important. Failures occurred especially during the endovascular phase and were often related to equipment or communication aspects. Interventions to improve procedural safety and quality of care should primarily target these specific areas.

Providing skilled birth attendants and emergency obstetric care to the poor through partnership with private sector obstetricians in Gujarat, India

PROBLEM

India has the world's largest number of maternal deaths estimated at 117,000 per year. Past efforts to provide skilled birth attendants and emergency obstetric care in rural areas have not succeeded because obstetricians are not willing to be posted in government hospitals at subdistrict level.

APPROACH

We have documented an innovative public-private partnership scheme between the Government of Gujarat, in India, and private obstetricians practising in rural areas to provide delivery care to poor women.

LOCAL SETTING

In April 2007, the majority of poor women delivered their babies at home without skilled care.

RELEVANT CHANGES

More than 800 obstetricians joined the scheme and more than 176,000 poor women delivered in private facilities. We estimate that the coverage of deliveries among poor women under the scheme increased from 27% to 53% between April and October 2007. The programme is considered very successful and shows that these types of social health insurance programmes can be managed by the state health department without help from any insurance company or international donor.

LESSONS LEARNED

At least in some areas of India, it is possible to develop large-scale partnerships with the private sector to provide skilled birth attendants and emergency obstetric care to poor women at a relatively small cost. Poor women will take up the benefit of skilled delivery care rapidly, if they do not have to pay for it.

A polymorphism in the VKORC1 regulator calumenin predicts higher warfarin dose requirements in African Americans

Warfarin demonstrates a wide interindividual variability in response that is mediated partly by variants in cytochrome P450 2C9 (CYP2C9) and vitamin K 2,3-epoxide reductase complex subunit 1 (VKORC1). It is not known whether variants in calumenin (CALU) (vitamin K reductase regulator) have an influence on warfarin dose requirements. We resequenced CALU regions in a discovery cohort of dose outliers: patients with high (>90th percentile, n = 55) or low (<10th percentile, n = 53) warfarin dose requirements (after accounting for known genetic and nongenetic variables). One CALU variant, rs339097, was associated with high doses (P = 0.01). We validated this variant as a predictor of higher warfarin doses in two replication cohorts: (i) 496 patients of mixed ethnicity and (ii) 194 African-American patients. The G allele of rs339097 (the allele frequency was 0.14 in African Americans and 0.002 in Caucasians) was associated with the requirement for a 14.5% (SD +/- 7%) higher therapeutic dose (P = 0.03) in the first replication cohort and a higher-than-predicted dose in the second replication cohort (allele frequency 0.14, one-sided P = 0.03). CALU rs339097 A>G is associated with higher warfarin dose requirements, independent of known genetic and nongenetic predictors of warfarin dose in African Americans.

Genetic and clinical predictors of warfarin dose requirements in African Americans

The objective of this study was to determine whether, in African-American patients, additional vitamin K oxidoreductase complex subunit 1 (VKORC1), cytochrome P450 2C9 (CYP2C9), CYP4F2, or apolipoprotein E (APOE) polymorphisms contribute to variability in the warfarin maintenance dose beyond what is attributable to the CYP2C9*2 and *3 alleles and the VKORC1 -1639G>A genotype. In a cohort of 226 African-American patients, weekly warfarin dose requirements were lower in those with the CYP2C9*8 allele (34 (30-47) mg; P = 0.023) and the CYP2C9 *2, *3, *5, *6, or *11 allele (33(28-40 mg); P < 0.001) as compared with those with the CYP2C9*1/*1 genotype (43 (35-56) mg). The combination of CYP2C9 alleles, VKORC1 -1639G>A genotype, and clinical variables explained 36% of the interpatient variability in warfarin dose requirements. By comparison, a model without the CYP2C9*5, *6, *8, and *11 alleles explained 30% of the variability in dose. No other VKORC1, CYP4F2, or APOE polymorphism contributed to the variance. The inclusion of additional CYP2C9 variants may improve the predictive ability of warfarin dosing algorithms for African Americans.

Reduced sleep as an obesity risk factor

Poor sleep has increasingly gained attention as a potential contributor to the recent obesity epidemic. The increased prevalence of obesity in Western nations over the past half-century has been paralleled by a severe reduction in sleep duration. Physiological studies suggest reduced sleep may impact hormonal regulation of appetite. Prospective studies suggest reduced habitual sleep duration as assessed by self-report is an independent risk factor for an increased rate of weight gain and incident obesity. Cross-sectional studies have demonstrated that the association between reduced sleep and obesity persists when sleep habits are measured objectively, that the association is as a result of elevations in fat and not muscle mass and that this association is not related to sleep apnoea. Thus, reduced sleep appears to represent a novel, independent risk factor for increased weight gain. Further research is needed to determine whether interventions aimed at increasing sleep may be useful in combating obesity.

Using linkage analysis to identify quantitative trait loci for sleep apnea in relationship to body mass index

To understand the genetics of sleep apnea, we evaluated the relationship between the apnea hypopnea index (AHI) and body mass index (BMI) through linkage analysis to identify genetic loci that may influence AHI and BMI jointly and AHI independent of BMI. Haseman-Elston sibling regression was conducted on AHI, AHI adjusted for BMI and BMI in African-American and European-American pedigrees. A comparison of the magnitude of linkage peaks was used to assess the relationship between AHI and BMI. In EAs, the strongest evidence for linkage to AHI was on 6q23-25 and 10q24-q25, both decreasing after BMI adjustment, suggesting loci with pleiotropic effects. Also, a promising area of linkage to AHI but not BMI was observed on 6p11-q11 near the orexin-2 receptor, suggesting BMI independent pathways. In AAs the strongest evidence of linkage for AHI after adjusting for BMI was on chromosome 8p21.3 with linkage increasing after BMI adjustment and on 8q24.1 with linkage decreasing after BMI adjustment. Novel linkage peaks were also observed in AAs to both BMI and AHI on chromosome 13 near the serotonin-2a receptor. These analyses suggest genetic loci for sleep apnea that operate both independently of BMI and through BMI-related pathways.

Heritability of upper airway dimensions derived using acoustic pharyngometry

Acoustic pharyngometry represents a simple, quick noninvasive method of measuring upper airway dimensions, which are predictive of sleep apnoea risk. The aim of the present study was to assess the genetic basis of upper airway size as determined using pharyngometry. Participants in the Cleveland Family Study aged >14 yrs underwent three acoustic pharyngometric measurements. Variance component models adjusted for age and sex were used to estimate the heritability of pharyngometry-derived airway measures. A total of 568 out of 655 (87%) subjects provided pharyngometric curves of sufficient quality. Although African-Americans tended to show narrower airways compared with white subjects, heritability patterns were similar in these two groups. The minimum cross-sectional area exhibited a heritability of 0.34 in white subjects and 0.39 in African-Americans, suggesting that 30-40% of the total variance in this measure is explained by shared familial factors. Estimates were unchanged after adjustment for body mass index or neck circumference. In contrast, oropharyngeal length did not show significant heritability in either ethnic group. The minimum cross-sectional area of the oropharynx is a highly heritable trait, suggesting the presence of an underlying genetic basis. These findings demonstrate the potential utility of acoustic pharyngometry in dissecting the genetic basis of sleep apnoea.

Effect of increased lung volume on sleep disordered breathing in patients with sleep apnoea

BACKGROUND

Previous studies have shown that changes in lung volume influence upper airway size and resistance, particularly in patients with obstructive sleep apnoea (OSA), and that continuous positive airway pressure (CPAP) requirements decrease when the lung volume is increased. We sought to determine the effect of a constant lung volume increase on sleep disordered breathing during non-REM sleep.

METHODS

Twelve subjects with OSA were studied during non-REM sleep in a rigid head-out shell equipped with a positive/negative pressure attachment for manipulation of extrathoracic pressure. The increase in lung volume due to CPAP (at a therapeutic level) was determined with four magnetometer coils placed on the chest wall and abdomen. CPAP was then stopped and the subjects were studied for 1 hour in three conditions (in random order): (1) no treatment (baseline); (2) at "CPAP lung volume", with the increased lung volume being reproduced by negative extrathoracic pressure alone (lung volume 1, LV1); and (3) 500 ml above the CPAP lung volume(lung volume 2, LV2).

RESULTS

The mean (SE) apnoea/hypopnoea index (AHI) for baseline, LV1, and LV2, respectively, was 62.3 (10.2), 37.2 (5.0), and 31.2 (6.7) events per hour (p = 0.009); the 3% oxygen desaturation index was 43.0 (10.1), 16.1 (5.4), and 12.3 (5.3) events per hour (p = 0.002); and the mean oxygen saturation was 95.4 (0.3)%, 96.0 (0.2)%, 96.3 (0.3)%, respectively (p = 0.001).

CONCLUSION

An increase in lung volume causes a substantial decrease in sleep disordered breathing in patients with OSA during non-REM sleep.

Study of ground water quality for irrigation in some villages of Surat District, Gujarat (India)

40 ground water samples of 10 villages in Surat district, Gujarat (India) were analyzed for their suitability for irrigation purpose. The mean values of 4 samples taken from each village have been reported in the present study. Ground water of the study area was classified according to sodium adsorption ratio (SAR), percentage sodium (PS), residual sodium carbonate (RSC), Kelley's ratio and electrical conductivity. The value of sodium adsorption ratio indicated that majority of samples (9 out of 10) fall in low sodium hazard category. As per classification made by Wilcox (1948), on the basis of percentage sodium and electrical conductivity, only 1 sample (Vesu) not found suitable for irrigation purpose while only 1 sample (Gaviyar) found in good category. The remaining 8 samples were in good to permissible and permissible to doubtful category. Ground water was also classified according to the classification of United States Salinity Laboratory based on sodium and salinity hazard.

Linkage of serum leptin levels in families with sleep apnea

OBJECTIVE

To identify regions on the genome linked to plasma leptin levels.

DESIGN

Full genome scan with 402 microsatellite markers, spaced approximately 10 cM apart. Data were analyzed using the Haseman-Elston regression linkage analysis.

SUBJECTS

A total of 160 sibling pairs from 59 predominantly African American, obese families recruited to participate in a genetic-epidemiological study of obstructive sleep apnea.

MEASUREMENTS

Serum leptin levels adjusted for age, sex, race and body mass index (BMI).

RESULTS

Suggestive linkage peaks were observed on chromosomes 2 (P=0.00170; marker D2S1384), 3 (P=0.00007; marker D3S3034), 4 (P=0.00020; marker D4S1652) and 21 (P=0.00053; marker D21s1411).

CONCLUSION

The peak on chromosome 3 is near the gene for glycogensynthase kinase 2 beta, an important factor in glucose homeostasis. Linkage was generally stronger after BMI adjustment, suggesting the potential influence of a number of metabolic pathways on leptin levels other than those that directly determine obesity levels. The evidence of linkage for leptin levels is consistent with prior linkage analyses for cholesterol, hypertension and other metabolic phenotypes.