APOE ε4, Alzheimer's disease neuropathology and sleep disturbance, in individuals with and without dementia.

BACKGROUND: Apolipoprotein E epsilon 4 (APOE-ε4) carrier status is an established risk factor for Alzheimer's disease (AD) dementia. It has also been linked with sleep disturbance in healthy older adults and increased insomnia risk. This association may be driven by the effect of APOE-ε4 on AD pathological change, itself associated with sleep abnormalities. To assess this relationship, we have evaluated post-mortem neuropathological findings in patients with and without cognitive impairment and AD pathology, who had extensive clinical assessment within 12 months of death. METHODS: This retrospective cohort study used UK Brain Banks Network data. Eligible subjects were aged over 50, with pre-mortem neuropsychiatry inventory scores of sleep disturbance (NPI-K), neurocognitive testing and functional cognitive status assessment (Clinical Dementia Rating scale). Neuropathological data included Thal phase, Braak stage and CERAD scores (measures of Aß plaque distribution, tangle distribution and neuritic plaque density, respectively) combined to form the National Institute on Aging Alzheimer's Association (NIA-AA) ABC score reflecting AD neuropathology. Participants with other significant intracerebral pathology or pathological features of non-AD dementia were excluded. Multivariate linear regression was performed with NPIK Global Score (NPIK frequency score multiplied by severity score) as the dependent variable and APOE-ε4 heterozygosity or homozygosity as independent variables. Covariates included age, gender, APOE-ε2 status and ABC NPI measures reflecting depression and anxiety. Further models stratified by ABC score and functional cognitive status were also produced. RESULTS: Seven hundred twenty-eight records were identified. Two hundred two participants were included in the final analysis: mean (SD) age 84.0 (9.2) and MMSE 14.0 (11.8). Mean sleep disturbance scores were highest in ε4 homozygosity (n=11), 4.55 (5.4); intermediate in ε4 heterozygosity (n=95), 2.03 (4.0); and lowest in non-ε4 carriers (n=96), 1.36 (3.3). Within the full sample, controlling for pathological status, age, gender, depression, anxiety and CDR-SOB status, APOE-ε4 homozygosity was associated with sleep disturbance (ß 2.53, p=0.034). APOE-ε4 heterozygosity was similarly associated in individuals without dementia (ß 1.21, p=0.048). CONCLUSION: These findings lend weight to the hypothesis that APOE-ε4 affects sleep by mechanisms independent of AD pathological change. Evaluation of those mechanisms would enhance understanding of sleep disturbance pathways and potentially provide treatment targets.

Sequential 3-dimensional computed tomography analysis of implant position following total shoulder arthroplasty.

BACKGROUND: Detection of postoperative component position and implant shift following total shoulder arthroplasty (TSA) can be challenging using routine imaging. The purpose of this study was to evaluate glenoid component position over time using 3-dimensional computed tomography (CT) analysis with minimum 2-year follow-up. METHODS: Twenty patients underwent primary TSA with sequential CT scanning of the shoulder: a preoperative study, an immediate postoperative study within 2 weeks of surgery, and a postoperative study performed at minimum 2-year follow-up (CT3). Postoperative glenoid component position and central peg osteolysis were assessed across the immediate postoperative CT scan and CT3. Glenoids with evidence of component shift and/or grade 1 central peg osteolysis on CT3 were considered at risk of loosening. RESULTS: Of the patients, 7 (35%) showed evidence of glenoid components at risk of loosening on CT3, 6 with component shift (3 with increased inclination alone, 1 with increased retroversion alone, and 2 with both increased inclination and retroversion). Significantly more patients with glenoid component shift had grade 1 central peg osteolysis on CT3 compared with those without shift (83% vs 7%, P = .002). One clinical failure occurred, with the patient undergoing revision to reverse TSA for rotator cuff deficiency. CONCLUSIONS: Three-dimensional CT imaging analysis following TSA identified changes in glenoid component position over time, with inclination being the most common direction of shift and grade 1 central peg osteolysis commonly associated with shift. These findings raise concern for glenoids at risk of loosening, but further follow-up is needed to determine the long-term clinical impact of these findings.

Low incidence of tendon rerupture after distal biceps repair by cortical button and interference screw.

BACKGROUND: The use of cortical suspensory fixation in conjunction with an interference screw to treat distal biceps ruptures has yielded favorable results. However, literature examining the incidence of fixation failure in a large consecutive series of patients treated with this technique is lacking. METHODS: A retrospective review of electronic medical records identified 170 distal biceps ruptures in 168 consecutive patients (164 men and 4 women) treated using a cortical button in conjunction with an interference screw. The study group was an average age of 48 years (range, 20-71 years). Records were reviewed from the time of the initial clinic visit to the most recent follow-up. Early failures were defined as those that occurred within 12 weeks of the index procedure. Failed repair was defined as tendon defect, deformity, or significant weakness in supination. RESULTS: The early incidence of failure was 1.2%, with 2 of the fixations meeting the criteria for failure. One patient had significant brachial artery thrombosis. Other complications included posterior interosseous nerve palsy, lateral antebrachial cutaneous nerve-related complication, and numbness about the radial nerve. CONCLUSION: The use of a cortical suspensory fixation device in conjunction with an interference screw is an effective method of repairing a distal biceps rupture, with a low early rate of failure.

Hip resurfacing arthroplasty in severely obese patients.

We conducted a study of outcomes of modern hip resurfacing arthroplasty (HRA) in severely obese patients. Patients who had undergone HRA and been followed for a minimum of 2 years were divided into 2 groups, those with body mass index under 35 (control, 366 hips) and those with body mass index of 35 or above (study, 63 hips). At mean follow-up of 41 months, there was no significant difference between the groups with respect to postoperative Harris Hip Scores, complication rates, and need for revision. Six revision surgeries were required in the control group (98.4% survival), and 2 were required in the study group (96.8% survival). These results suggest that severely obese patients should be considered candidates for HRA.

Surgically treated humeral shaft fractures following shoulder arthroplasty.

BACKGROUND: We reviewed a consecutive series of patients with a humeral fracture around either an anatomic or a reverse shoulder prosthesis treated with either open reduction and internal fixation (ORIF) or revision shoulder arthroplasty. The purposes of the study were to (1) describe the treatment of these fractures by either method, (2) report the outcomes, and (3) assess the validity of a current classification system. METHODS: Indications for surgery were a displaced unstable fracture, a fracture around a loose humeral stem, or a patient who was unable to tolerate conservative treatment. Outcomes were reported for two groups (patients treated with revision arthroplasty and those treated only with ORIF) and included American Shoulder and Elbow Surgeons (ASES) scores, radiographic evidence of fracture union, and complications. RESULTS: The mean ASES score for the entire cohort was 50.3 (95% confidence interval: 41.2 to 59.5). Thirty-five of the thirty-six fractures healed, in a mean of 7.2 months (range, 3.25 to 13.5 months). Complications occurred in fourteen (39%) of the thirty-six patients. Our ability to classify these fractures with a previously defined system had a low interobserver reliability (mean kappa, 0.37; range, 0.24 to 0.50) and a high intraobserver reliability (mean kappa, 0.69; range, 0.52 to 0.89). CONCLUSIONS: Periprosthetic fracture around a humeral stem implant is a difficult clinical problem involving complex decision-making. Fracture union occurred in 97% of our patients. Complications were frequent, and a reoperation was required in 19% of the patients. More than half of the patients in our study had a loose humeral component that required revision.

Prognosis for recovery of posterior interosseous nerve palsy after distal biceps repair.

BACKGROUND: There is very little information on the incidence of and usual recovery period for posterior interosseous nerve (PIN) palsies after distal biceps repair. This study examined the incidence and the time to resolution of PIN palsies in a large consecutive series of primary distal biceps repairs. MATERIALS AND METHODS: A retrospective review was performed of a consecutive series of patients treated by 34 fellowship-trained upper extremity surgeons with primary distal biceps repair through a single anterior incision technique. Patients' records were reviewed to determine how many experienced a postoperative PIN palsy, defined as postoperative digital extension weakness on clinical examination. Demographic information, surgical fixation used, and clinical resolution was collect for these patients. All patients had clinical follow-up until complete resolution of PIN palsy symptoms. RESULTS: We found 280 patients who were treated with a single-incision technique and 1 of 2 methods of biceps tendon fixation. Of these, 9 (3.2%) developed a postoperative PIN palsy after primary distal biceps repair. These 9 patients had complete lack of finger and thumb extension at the first postoperative visit and had complete resolution of symptoms at an average of 86 days (range, 41-145 days). CONCLUSIONS: The incidence of PIN palsy after a single-incision distal biceps repair was 3.2% in our series. These injuries typically resolve within 3 months, and at the latest, 5 months after surgery.

Complications following distal biceps repair.

PURPOSE: Distal biceps rupture is a relatively uncommon injury. Surgical repair is performed in patients who seek increased flexion and supination strength over that which results from nonoperative treatment. The purpose of this study was to evaluate complications associated with surgical repair of the distal biceps tendon in a large series of patients. METHODS: We retrospectively reviewed 198 consecutive patients with distal biceps ruptures treated with surgical repair, and evaluated time from injury to repair, surgical technique, and complications. RESULTS: A total of 72 patients (36%) developed complications; 6 patients underwent additional surgery. Minor complications included lateral antebrachial cutaneous nerve paresthesia (26%), radial sensory nerve paresthesia (6%), and superficial infection (2%). Major complications included posterior interosseous nerve injury (4%), symptomatic heterotropic ossification (3%), and re-rupture (2%). CONCLUSIONS: Minor complications were common after distal biceps tendon repair; however, most were sensory nerve injuries that resolved with time. Major complications were infrequent, and few patients required revision surgery. Complications were more common after distal biceps tendon repair performed more than 28 days after rupture. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Dentistry-based approaches to sleep-disordered breathing, algorithms, and multidisciplinary perspectives.

Sleep disorders affect more than 20 percent of the U.S. population, but less than 7 percent have been medically diagnosed. Dentists are ideally positioned to identify many patients who fall under the grouping of sleep-disordered breathing. This paper presents perspectives on sleep-related issues from various medical specialties with a goal to broaden the dentist's appreciation of this topic and open avenues of communication. Algorithms are proposed to guide dentists following positive screenings for sleep-disordered breathing.

Evaluation of a nutrition education intervention for women residents of Washington, DC, public housing communities.

We designed, implemented and evaluated an educational intervention to increase fruit and vegetable consumption among urban African-American women. Women aged 20-50 years (n=212) from 11 public housing communities participated in seven 90-min classes with a professional nutritionist. Our prospective pre- and post-test design, with 4-month follow-up, assessed the relationship between attendance and dietary change, using three 24-hour recalls per time point. Mean change in average daily dietary values for fruits and vegetables, calories and percent calories from fat (post-test versus pre-test, follow-up versus pre-test) was compared by class attendance, to evaluate the impact of class attendance on dietary change. Attendance varied from zero (35%) to five to seven classes (42%). Baseline dietary recalls showed average daily consumption of 3.05 servings of fruits and vegetables, 2416 calories and 35.8% calories from fat. No improvements in fruit and vegetable consumption, but statistically significant decreases in total calories and percent calories from fat, were seen at both endpoints. Women attending five to seven classes had the greatest dietary improvements, averaging, at post-test and follow-up, respectively, 246.2 and 324.5 fewer calories and 3.08 and 2.97% fewer calories from fat. Results suggest that, for some residents of low-resource communities, small group interventions are popular, effective vehicles for nutrition education.

The influence of stigma on the sexual risk behavior of rural men who have sex with men.

Research investigating predictors of risky sexual behavior of rural MSM is sparse, even though the prevalence of HIV in rural areas has increased. This study explored two sets of predictors of 93 rural MSM's levels of risky sexual behavior: mental health variables and stigma emanating from men's family members, health care professionals, and people in the rural communities in which they live. Over 47% of the men were found to be at modified high to high risk. Logistic regression using a continuation logit model was used to test the relationship of the predictor variables and the four levels of risk. Findings indicate that self-esteem was predictive of the highest sexual risk behavior but not lower levels of risk. Stigma was predictive of modified high sexual risk when compared to low and no risk categories. No variables differentiated men at low risk from men at no risk.

A discussion of chain referral as a method of sampling hard-to-reach populations.

Nursing research often requires inquiry into sensitive topics that involve hidden or hard- to reach populations. However, identifying and sampling these populations for research purposes is often fraught with difficulties. Barriers include society's lack of tolerance of diverse groups, social stigma, concern for issues of confidentiality, and fear of exposure because of possible threats to security. Chain referral sampling techniques are proposed to minimize bias while maintaining privacy and confidentiality. Techniques of chain referral sampling are detailed for use in researching sensitive topics and hidden populations. When carefully planned and executed, this sampling design offers transcultural nurse researchers a reasonable method for accessing and studying special populations that are particularly hard-to-reach.