Hyun J. Lim

Meta-analysis of upper probe measurements in normal subjects and patients with laryngopharyngeal reflux

We report a meta-analysis of a series of studies in which 24-hour ambulatory pH monitoring was performed in 1) normal subjects, 2) the normal control subjects in studies of laryngopharyngeal reflux (LPR), and 3) the patients with LPR in these controlled studies. The statistical analysis utilized the fixed-effects model by Mantel-Haenszel and the random-effects mixed model. There were 16 studies from the past 12 years that fulfilled the inclusion criteria. They involved 793 subjects (264 normal and 529 with LPR). The numbers of positive pharyngeal reflux events for normal subjects and for patients with LPR differed with a p value of <.0001. There was also a significant difference in the mean percentage of acid exposure times between normal subjects and patients with LPR (p = .003). We conclude that the upper probe gives accurate and consistent information in normal subjects and patients with LPR. The numbers of reflux events and acid exposure times are most important in distinguishing normal subjects from patients with LPR. The technology and methodology of probe testing is quite reliable and is consistent on a worldwide basis.

Transpalatal advancement pharyngoplasty outcomes compared with uvulopalatopharygoplasty

Objective: Uvulopalatopharyngoplasty (UPPP) success rates in patients classified with Friedman stage 3 is reported as 8%. Surgical failure may result from persistent obstruction at the palate, which may be addressed by pharyngoplasty with palatal advancement (PA). The effectiveness of PA versus UPPP was evaluated by using polysomnographic outcomes in a retrospective cohort of patients classified with Friedman stage 3. Methods: Surgical records were reviewed for PA (n = 47) and UPPP (n = 124). Clinical records were reviewed and reclassified by Friedman stage. Respiratory data were collected from overnight polysomnography. Statistical analysis was conducted of continuous variables (ANOVA), categorical variables (χ 2 ), and adjusted odds ratios by using logistic regression. Results: PA (n = 30) and UPPP (n = 44) did not differ in baseline apnea hypopnea index (AHI), age, or BMI. Both PA (48.3 ± 24.6 to 19.8 ± 16.8 events per hour, P < 0.000) and UPPP (47.9 ± 30.0 to 30.9 ± 24.2 events per hour, P < 0.000) improved with surgery. In the PA group, final AHI was lower (17.1 ± 30.1 versus 28.5 ± 25.6, P < 0.04) and postoperative change was greater (30.9 ± 24.2 versus 19.8 ± 16.8, P < 0.02). For patients with Friedman stage 3, odds ratio of having an AHI of <20 events per hour and a greater than 50% reduction with PA compared with UPPP was 3.80 (95% CI, 1.41-10.29, P < 0.013). Adjusted for age, body mass index, preoperative apnea severity, and tongue-base surgery, OR was 5.77 (95% CI of 1.80-17.98). Conclusions: Polysomnographic outcomes using AHI support the use of palatopharyngoplasty using palatal advancement as an effective treatment of obstructive sleep apnea. PA may offer benefit over UPPP alone in patients classified with Friedman stage 3.

Opacification of the Genitourinary Collecting System During MDCT Urography with Enhanced CT Digital Radiography: Nonsaline Versus Saline Bolus

OBJECTIVE The purpose of this study was to determine whether a saline bolus during CT urography improves urinary collecting system opacification and whether the addition of enhanced CT digital radiography (CTDR) improves urinary collecting system visualization with or without a saline bolus. MATERIALS AND METHODS One hundred eight CT urography and enhanced CTDR examinations were reviewed. Fifty-four patients were given a saline bolus during CT urography, and 54 patients underwent CT urography without a saline bolus. Urinary collecting system opacification was evaluated by group (saline vs nonsaline), imaging technique (CT urography alone vs CT urography plus enhanced CTDR), number of enhanced CTDR images, and site of nonopacified urinary segments. Using a multivariate logistic regression model, we determined significance of variables and odds of complete opacification. RESULTS In the saline group, 248 nonopacified sites were identified on CT urography alone and 95 sites with CT urography plus enhanced CTDR. In the nonsaline group, 185 nonopacified sites were identified on CT urography alone and 59 sites with CT urography plus enhanced CTDR. Combining both groups, 433 nonopacified sites were identified with CT urography alone and 154 sites with CT urography plus enhanced CTDR. Multivariate logistic regression showed significance for group (p = 0.010), imaging method (p < 0.0001), number of enhanced CTDR images (p = 0.048), and site of segment opacification (p < 0.0001). The renal pelvis shows the greatest odds and the distal ureter the lowest odds for complete opacification by group or imaging method. CONCLUSION The addition of a saline bolus offers no improvement, whereas the addition of enhanced CTDR offers significant improvement in collecting system opacification during CT urography.

Endothelium-derived microparticles inhibit human cardiac valve endothelial cell function.

Elevated numbers of endothelium-derived microparticles (EMPs) in the circulation are found in a variety of critical illnesses. EMPs have been associated with vascular dysfunction, including thrombotic complications and loss of normal vascular reactivity, common responses associated with cardiac valve injury. However, the exact mechanisms of this dysfunction and the potential impact on cardiac endothelium are unknown. We hypothesize that pathologic levels of circulating EMPs negatively regulate proliferation and migration of valvular endothelial cells (ECs), leading to downstream endothelial dysfunction. EMPs were generated from plasminogen activation inhibitor 1-stimulated human umbilical vein endothelial cells (HUVECs). Human mitral valve endothelial cells (HMVECs) were isolated and characterized by platelet endothelial cell-derived adhesion molecule-1 (PECAM-1, or CD31) and von Willebrand factor immunocytochemistry. HMVECs were treated with increasing EMP doses, and then, the effects of EMPs on growth factor-induced proliferation and migration were tested. Proliferation was assessed by 3H-thymidine incorporation. EC migration was assayed by photographing microtubules of HMVECs and HUVECs in fibrin gel incubated with EMPs ± growth factors for 48 h. The EMP effects on nonvalve HUVECs were tested in parallel. EMPs inhibited HMVEC proliferation at high doses but stimulated HUVEC proliferation at all doses. In HMVECs, EMPs inhibited basic fibroblast growth factor- and vascular endothelial growth factor-induced proliferation and migration. Taken together, these data suggest EMPs regulate valvular EC proliferation in a dose-dependent manner and, furthermore, modulate growth factor signaling in ECs. These results implicate EMPs as a possible source of downstream EC dysfunction in disease states. EMPs may play a role in valvular leaflet injury in human disease by inhibiting normal growth and repair of endothelium.

Methods of competing risks analysis of end-stage renal disease and mortality among people with diabetes

BackgroundWhen a patient experiences an event other than the one of interest in the study, usually the probability of experiencing the event of interest is altered. By contrast, disease-free survival time analysis by standard methods, such as the Kaplan-Meier method and the standard Cox model, does not distinguish different causes in the presence of competing risks. Alternative approaches use the cumulative incidence estimator by the Cox models on cause-specific and on subdistribution hazards models. We applied cause-specific and subdistribution hazards models to a diabetes dataset with two competing risks (end-stage renal disease (ESRD) or death without ESRD) to measure the relative effects of covariates and cumulative incidence functions.ResultsIn this study, the cumulative incidence curve of the risk of ESRD by the cause-specific hazards model was revealed to be higher than the curves generated by the subdistribution hazards model. However, the cumulative incidence curves of risk of death without ESRD based on those three models were very similar.ConclusionsIn analysis of competing risk data, it is important to present both the results of the event of interest and the results of competing risks. We recommend using either the cause-specific hazards model or the subdistribution hazards model for a dominant risk. However, for a minor risk, we do not recommend the subdistribution hazards model and a cause-specific hazards model is more appropriate. Focusing the interpretation on one or a few causes and ignoring the other causes is always associated with a risk of overlooking important features which may influence our interpretation.

Exploring contraceptive use differentials in Sub-Saharan Africa through a workforce lens.

Globally 56% of all married women are using a modern method of contraception up from less than 10% in 1960. In sub-Saharan Africa however only 19% of married women are using a modern method of contraception. Since nearly all family planning services require assistance from a health worker access to health workers is a principal supply-side determinant of family planning service use. This technical brief presents findings from a study that explored if and how health workforce measures differ between eastern and western Africa in an effort to identify factors that may have helped some countries to achieve important gains in contraceptive prevalence while other countries have not. The findings raise questions about whether government commitment and certain policy choices vis-a-vis health workforce distribution and qualifications—even when absolute levels of health worker density are low—could make a difference in the provision of family planning services in resource-constrained countries.Supporting individuals as they disclose their HIV serostatus may lead to a variety of individual and public health benefits. However, many women living with HIV are hesitant to disclose their HIV status due to fear of negative outcomes such as violence, abandonment, relationship dissolution and stigma.

Does medical training promote or deter self-directed learning? A longitudinal mixed-methods study.

Purpose The School of Medicine, University of Saskatchewan curriculum promotes self-direction as one of its learning philosophies. The authors sought to identify changes in self-directed learning (SDL) readiness during training. Method Guglielmino’s SDL Readiness Scale (SDLRS) was administered to five student cohorts (N = 375) at admission and the end of every year of training, 2006 to 2010. Scores were analyzed using repeated-measurement analysis. A focus group and interviews captured students’ and instructors’ perceptions of self-direction. Results Overall, the mean SDLRS score was 230.6; men (n = 168) 229.5; women (n = 197) 232.3, higher than in the average adult population. However, the authors were able to follow only 275 students through later years of medical education. There were no significant effects of gender, years of premedical training, and Medical College Admission Test scores on SDLRS scores. Older students were more self-directed. There was a significant drop in scores at the end of year one for each of the cohorts (P < .001), and no significant change to these SDLRS scores as students progressed through medical school. Students and faculty defined SDL narrowly and had similar perceptions of curricular factors affecting SDL. Conclusions The initial scores indicate high self-direction. The drop in scores one year after admission, and the lack of change with increased training, show that the current educational interventions may require reexamination and alteration to ones that promote SDL. Comparison with schools using a different curricular approach may bring to light the impact of curriculum on SDL.

Effect of Transfer, Lifting, and Repositioning (TLR) Injury Prevention Program on Musculoskeletal Injury Among Direct Care Workers

Musculoskeletal injuries among health care workers is very high, particularly so in direct care workers involved in patient handling. Efforts to reduce injuries have shown mixed results, and strong evidence for intervention effectiveness is lacking. The purpose of our study was to evaluate the effectiveness of a Transfer, Lifting and Repositioning (TLR) program to reduce musculoskeletal injuries (MSI) among direct health care workers. This study was a pre- and post-intervention design, utilizing a nonrandomized control group. Data were collected from the intervention group (3 hospitals; 411 injury cases) and the control group (3 hospitals; 355 injury cases) for periods 1 year pre- and post-intervention. Poisson regression analyses were performed. Of a total 766 TLR injury cases, the majority of injured workers were nurses, mainly with back, neck, and shoulder body parts injured. Analysis of all injuries and time-loss rates (number of injuries/100 full-time employees), rate ratios, and rate differences showed significant differences between the intervention and control groups. All-injuries rates for the intervention group dropped from 14.7 pre-intervention to 8.1 post-intervention. The control group dropped from 9.3 to 8.4. Time-loss injury rates decreased from 5.3 to 2.5 in the intervention group and increased in the control group (5.9 to 6.5). Controlling for group and hospital size, the relative rate of all-injuries and time-loss injuries for the pre- to post-period decreased by 30% (RR = 0.693; 95% CI = 0.60–0.80) and 18.6% (RR = 0.814; 95% CI = 0.677–0.955), respectively. The study provides evidence for the effectiveness of a multifactor TLR program for direct care health workers, especially in small hospitals.

Relationship between the Pittsburgh Sleep Quality Index and the Epworth Sleepiness Scale in a sleep laboratory referral population

Background Sleep health questionnaires are often employed as a first assessment step for sleep pathology. The Epworth Sleepiness Scale (ESS) and the Pittsburgh Sleep Quality Index (PSQI) are two commonly employed questionnaire instruments. Aspects of sleep health may be measured differently depending on choice of instrument. Objectives In a patient population at high risk for sleep disorders, referred for polysomnography (PSG), we evaluated the level of association between results from these two instruments. Questionnaire results were also compared with measured PSG parameters. Methods Records of patients undergoing overnight PSG in the sleep laboratory between February–June 2011 were retrospectively reviewed for eligibility. Inclusion criteria were met by 236 patients. PSQI and ESS scores, demographic information, and PSG data were extracted from each record for analysis. Four subgroups based on normal/abnormal values for ESS and PSQI were evaluated for between-group differences. Results Of 236 adult participants, 72.5% were male, the mean age was 52.9 years (13.9), mean body mass index (BMI) 34.4 kg/m2 (8.3), mean ESS 9.0 (4.8; range: 0–22), PSQI mean 8.6 (4.2; range: 2–19). The Pearson correlation coefficient was r = 0.13 (P = 0.05) for association between ESS and PSQI. Participants with an abnormal ESS were more likely to have an abnormal PSQI score (odds ratio 1.9 [1.1–3.6]; P = 0.03). Those with an abnormal ESS had higher BMI (P = 0.008) and higher apnea–hypopnea indexes (AHI) (P = 0.05). Differences between the four subgroups were observed for BMI and sex proportions, but not for AHI. Conclusions We observed limited association between these two commonly used questionnaire instruments, the ESS and the PSQI. These two questionnaires appear to evaluate different aspects of sleep. In terms of clinical application, for global assessment of patients with sleep problems, care should be taken to include instruments measuring different facets of sleep health.

Hypersomnolence and sleep disorders in a rheumatic disease patient population.

Objectives:There is increasing awareness of the importance of sleep in health maintenance. Our primary objective was to evaluate prevalence of excess daytime sleepiness in a rheumatic disease patient population. Secondary objectives included evaluation of prevalence of abnormal sleep quality and primary sleep disorders. Methods:Consecutive Rheumatology clinic patients were invited to participate in a self-administered questionnaire study. Included were measures for pain, fatigue, and global functioning, modified Health Assessment Questionnaire, Epworth Sleepiness Score (ESS), Pittsburgh Sleep Quality Index (PSQI), Berlin Score, diagnostic criteria for restless legs syndrome (RLS), Centre for Epidemiologic Studies Depression score (CES-D), stress scores, and the short form-36 quality of life instrument. Results:Of 507 consecutive patients invited to participate, 423 agreed. Mean age was 52.1 years; 26% were male. Prevalence of excessive sleepiness (ESS >10) was 25.7%, abnormal sleep quality (PSQI >5) was 67.3%, high risk for obstructive sleep apnea Berlin scores were present in 35.2% and 24% of participants met criteria for RLS. Significantly worse pain, fatigue, global function, short form-36 summary scores, modified Health Assessment Questionnaire, depression, and stress scores were present in patients with higher ESS and PSQI scores. No significant differences in sleep assessment scores were observed between specific rheumatic disease groups. Conclusions:Our findings suggest a high prevalence of unrecognized hypersomnolence, poor sleep quality, and primary sleep disorders in rheumatology patients. We suggest evaluation of sleep health be incorporated into standard clinical assessments of all rheumatology patients. We would recommend this evaluation include the ESS and the criteria for RLS.