The Kaiser Permanente shoulder arthroplasty registry: results from 6,336 primary shoulder arthroplasties.

BACKGROUND AND PURPOSE: Shoulder arthroplasty is being performed in the United States with increasing frequency. We describe the medium-term findings from a large integrated healthcare system shoulder arthroplasty registry. PATIENTS AND METHODS: Shoulder arthroplasty cases registered between January 2005 and June 2013 were included for analysis. The registry included patient characteristics, surgical information, implant data, attrition, and patient outcomes such as surgical site infections, venous thromboembolism, and revision procedures. RESULTS: During the study period, 6,336 primary cases were registered. Median follow-up time for all primaries was 3.3 years; 461 cases were lost to follow-up by ending of health plan membership. Primary cases were predominantly female (56%) and white (81%), with an average age of 70 years. The most common reason for surgery was osteoarthritis in 60% of cases, followed by acute fracture (17%) and rotator cuff tear arthropathy (15%). In elective shoulder arthroplasty procedures, 200 all-cause revisions (4%) were reported, with glenoid wear being the most common reason. INTERPRETATION: Most arthroplasties were elective procedures: over half performed for osteoarthritis. Glenoid wear was the most common reason for revision of primary shoulder arthroplasty in elective cases.

Injury pathology at the time of anterior cruciate ligament reconstruction associations with self-assessment of knee function.

OBJECTIVE: To evaluate the association of preoperative Knee Injury and Osteoarthritis Outcome Score (KOOS) and structural injuries reported at the time of anterior cruciate ligament reconstruction (ACLR). DESIGN: Cross-sectional study. SETTING: Three medical centers in California. PARTICIPANTS: Primary ACLRs (N = 636) performed between January 2009 and June 2010. INDEPENDENT VARIABLES: The 5 KOOS subscales: pain, other symptoms, activities of daily living (ADL), function in sport and recreation (Sport/Rec), and quality of life (QoL). MAIN OUTCOME MEASURES: Associated injuries (cartilage, medial meniscus, lateral meniscus, other ligaments), identified at the time of ACLR. RESULTS: Sixty-eight percent of the cohort was male and the median age was 26 years. No gender differences in KOOS were observed. No KOOS differences were observed by race, except in Sport/Rec. Younger patients reported higher KOOS. Pain and ADL scores were not associated with any concurrent injury. A 10-point increase in KOOS symptoms subscale was associated with 22% higher likelihood of isolated ACL, 13% lower likelihood of medial meniscus injury, and 10% lower likelihood of lateral meniscus. A 10-point increase in the KOOS Sport/Rec subscale score was associated with 8% higher likelihood of isolated ACL and 9% lower likelihood of medial meniscus injury. A 10-point increase in the KOOS QoL subscale was associated with 15% lower likelihood of medial meniscus injury. CONCLUSIONS: Weak associations between the symptoms, Sports/Rec, and QoL subscales and structural injuries at ACLR were observed. The KOOS and its subscales are not useful as indicators of the pattern or severity of preoperative injury of patients presenting for ACLR.

Sex and risk of hip implant failure: assessing total hip arthroplasty outcomes in the United States.

IMPORTANCE: The role of sex in relationship to implant failure after total hip arthroplasty (THA) is important for patient management and device innovation. OBJECTIVE: To evaluate the association of sex with short-term risk of THA revision after adjusting for patient, implant, surgery, surgeon, and hospital confounders. DESIGN AND SETTING: A prospective cohort of patients enrolled in a total joint replacement registry from April 1, 2001, through December 31, 2010. PARTICIPANTS: Patients undergoing primary, elective, unilateral THA. MAIN OUTCOME MEASURES: Failure of THA, defined as revision procedure for (1) any reason, (2) septic reason, or (3) aseptic reason after the index procedure. RESULTS: A total of 35,140 THAs with 3.0 years of median follow-up were identified. Women constituted 57.5% of the study sample, and the mean (SD) patient age was 65.7 (11.6) years. A higher proportion of women received 28-mm femoral heads (28.2% vs 13.1%) and had metal on highly cross-linked polyethylene-bearing surfaces (60.6% vs 53.7%) than men. Men had a higher proportion of 36-mm or larger heads (55.4% vs 32.8%) and metal on metal-bearing surfaces (19.4% vs 9.6%). At 5-year follow-up, implant survival was 97.4% (95% CI, 97.2%-97.6%). Device survival for men (97.7%; 95% CI, 97.4%-98.0%) vs women (97.1%; 95% CI, 96.8%-97.4%) was significantly different (P = .01). After adjustments, the hazards ratios for women were 1.29 (95% CI, 1.11-1.51) for all-cause revision, 1.32 (95% CI, 1.10-1.58) for aseptic revision, and 1.17 (95% CI, 0.81-1.68) for septic revision. CONCLUSIONS: After considering patient-, surgery-, surgeon-, volume-, and implant-specific risk factors, women had a 29% higher risk of implant failure than men after THA in this community-based sample.

Risk of revision for fixed versus mobile-bearing primary total knee replacements.

BACKGROUND: Mobile-bearing total knee arthroplasty prostheses were developed to reduce wear and revision rates; however, these benefits remain unproven. The purposes of this study were to compare the short-term survivorship and to determine risk factors for revision of mobile-bearing and fixed-bearing total knee replacements. METHODS: A prospective cohort study of primary total knee arthroplasties performed from 2001 to 2009 was conducted with use of a community total joint replacement registry. Patient characteristics and procedure details were identified. Cox regression models were used. Bearing type was investigated as a risk factor for revision while adjusted for other risk factors such as age, American Society of Anesthesiologists (ASA) score, body mass index, sex, race, diagnosis, bilateral procedures, cruciate-retaining versus posterior-stabilized components, surgical approach, fixation, patellar resurfacing, hospital and surgeon volumes, and fellowship training. RESULTS: The study cohort consisted of 47,339 total knee arthroplasties, with 62.6% of the procedures in women. Fixed bearings were used in 41,908 knees (88.5%) and mobile bearings in 4830 (10.2%). Rotating-platform designs were used in all mobile-bearing total knee arthroplasties (3112 had a Rotating-Platform Press-Fit Condylar posterior-stabilized design; 1053, a Low Contact Stress [LCS] design; and 665, a Rotating-Platform Press-Fit Condylar cruciate-retaining design). Patients who received fixed-bearing total knee arthroplasty systems were older (mean age, 68.1 years) than those who received mobile-bearing total knee arthroplasty systems (mean age, 62.2 years); the difference was significant (p < 0.001). Overall, 515 knees (1.1%) were revised for reasons other than infection. The survival rate was 97.8% (95% confidence interval [CI], 97.4% to 98.0%) at 6.7 years. The adjusted risk of aseptic revision for the LCS total knee replacements was 2.01 times (95% CI, 1.41 to 2.86) higher than that for fixed-bearing total knee replacements (p < 0.001).There was no significant revision risk for the other mobile-bearing total knee arthroplasty systems. There was no association with surgeon and hospital case volumes and the risk of revision total knee arthroplasty. CONCLUSIONS: Our study suggests the benefit of potential long-term wear reduction with the LCS implant may not be realized in a community-based setting, where a variety of surgical skills, surgical experience, and diverse patient demographic factors may affect early outcomes. LEVEL OF EVIDENCE: Therapeutic Level II.

Gastrointestinal lymphomas: Morphology, immunophenotype and molecular features.

Primary gastrointestinal lymphoma comprises 10-15% of all non-Hodgkin lymphomas and encompasses 30-40% of the total extranodal lymphomas. Approximately 60-75% of cases occur in the stomach, and then the small bowel, ileum, cecum, colon and rectum. Lymphoid neoplasms may consist of mature B, T and less commonly extranodal NK/T cells. Of these, the two most frequently encountered histologic subtypes are extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma), where Helicobacter pylori infection is implicated in a number of cases, and diffuse large B cell lymphoma. Several B cell lymphomas are associated with chromosomal aberrations. Enteropathy-associated T cell lymphoma, type I in particular, usually arises in a background of celiac disease. T cell gene rearrangement confirms clonality. NK/T cell neoplasms are invariably associated with Epstein-Barr virus infection and are often aggressive; thus, differentiation from a benign NK-cell enteropathy is paramount. Although incidence of other hematopoietic malignancies in the gastrointestinal tract such as plasma cell myeloma associated with amyloidosis, plasmablastic lymphoma, Hodgkin disease, histiocytic sarcoma and mast cell sarcoma is extremely rare, these entities have been documented, with the latter two demonstrating aggressive clinical behavior. Endoscopic ultrasonography is an important adjunct in disease staging and follow-up. Conservative antibiotic treatment of stage I MALT lymphomas with associated Helicobacter pylori infection achieves good clinical outcome with high remission rate. Chemotherapy, radiation and rarely surgery are reserved for advanced diseases or cases resistant to conservative therapy and those not associated with Helicobacter pylori infection.

Evaluation of total hip arthroplasty devices using a total joint replacement registry.

PURPOSE: The purpose of this paper is to describe the infrastructure of the total joint replacement registry of a large integrated healthcare system's and emphasize challenges associated with orthopedic device classification and evaluation. METHODS: Using a large integrated healthcare system innovative infrastructure including electronic health record data, administrative data sources, and registry data collection, we evaluated device choice and outcomes of total hip arthroplasty (THA). Devices were classified into type of bearing surface (alternative versus traditional). Multiple imputation was used to accommodate missing data, and a logistic regression model was applied to assess the impact of patient and surgeon factors on choice of bearing surface. A Cox regression model was used to evaluate risk of aseptic revision while controlling for surgeon, site, and patient characteristics. Adjusted cumulative probability-of-event curves were created, comparing survival of alternative against traditional bearings of devices, with aseptic revision as the outcome of interest. RESULTS: The study sample consisted of 25,377 primary THAs with an average follow-up of 2.7 years. Choice of bearing surface varied by surgeon and patient characteristics. After adjusting for patient, surgeon, and hospital covariates, results showed that the risk of aseptic revision associated with alternative bearings did not differ significantly from traditional bearing surfaces (hazard ratio = 1.33; 95% confidence interval: 0.90, 1.98). CONCLUSIONS: Clinically rich data from a registry with linkages to electronic health records and other administrative databases improve identification of exposures, outcomes, and patient subgroups in medical device evaluation. These various data sources facilitate refined adjustment for potential confounders such as hospital, surgeon, and patient factors and ensure comprehensive device performance evaluation within registries.

Leveraging electronic medical records for surveillance of surgical site infection in a total joint replacement population.

OBJECTIVE: To evaluate whether a hybrid electronic screening algorithm using a total joint replacement (TJR) registry, electronic surgical site infection (SSI) screening, and electronic health record (EHR) review of SSI is sensitive and specific for SSI detection and reduces chart review volume for SSI surveillance. DESIGN: Validation study. SETTING: A large health maintenance organization (HMO) with 8.6 million members. METHODS: Using codes for infection, wound complications, cellullitis, procedures related to infections, and surgeon-reported complications from the International Classification of Diseases, Ninth Revision, Clinical Modification, we screened each TJR procedure performed in our HMO between January 2006 and December 2008 for possible infections. Flagged charts were reviewed by clinical-content experts to confirm SSIs. SSIs identified by the electronic screening algorithm were compared with SSIs identified by the traditional indirect surveillance methodology currently employed in our HMO. Positive predictive values (PPVs), negative predictive values (NPVs), and specificity and sensitivity values were calculated. Absolute reduction of chart review volume was evaluated. RESULTS: The algorithm identified 4,001 possible SSIs (9.5%) for the 42,173 procedures performed for our TJR patient population. A total of 440 case patients (1.04%) had SSIs (PPV, 11.0%; NPV, 100.0%). The sensitivity and specificity of the overall algorithm were 97.8% and 91.5%, respectively. CONCLUSION: An electronic screening algorithm combined with an electronic health record review of flagged cases can be used as a valid source for TJR SSI surveillance. The algorithm successfully reduced the volume of chart review for surveillance by 90.5%.

Incidence and nature of cognitive decline over 1 year among HIV-infected former plasma donors in China.

OBJECTIVE: To quantify and characterize the nature of cognitive change over 1 year in a cohort of HIV-positive former plasma donors in rural China. DESIGN: The present study is an observational cohort study. METHODS: One hundred and ninety-two HIV-positive and 101 demographically comparable HIV-negative individuals, all former plasma donors, who lived in a rural part of China, received comprehensive medical and neuropsychological examinations. At study entry, 56% of HIV-positive group was on combination antiretroviral treatment and 60.9% at follow-up. Multiple regression change score approach was used with the HIV-negative sample to develop norms for change that would be then applied to the HIV-positive participants. Follow-up test scores adjusted for the control group practice effect. RESULTS: Fifty-three HIV-positive individuals (27%) developed significant cognitive decline as compared with five (5%) HIV-negative individuals. Cognitive decline was predicted at baseline by AIDS status, lower nadir CD4, and worse processing speed; at follow-up, it was associated with lower current CD4 cell count and failure of viral suppression on combination antiretroviral treatment. Neuropsychological decline also was associated with decreased independence in activities of daily living. Using neuropsychological impairment scores that were corrected for 'practice' on repeated testing, we found that among the decliners, 41.5% (N = 22) had incident impairment, whereas 38% (N = 20) declined within the impaired range and another 20.7% (N = 11) declined within the normal range. CONCLUSION: The present study demonstrates that despite ongoing combination antiretroviral treatment, cognitive decline in HIV-positive people is common over a 1-year follow-up. Regression-based norms for change on western neuropsychological tests can be used to detect disease-related cognitive decline in a developing country.

Alteration of Methamphetamine-induced stereotypic behaviour in transgenic mice expressing HIV-1 envelope protein gp120.

The use of drugs for recreational purposes, in particular Methamphetamine, is associated with an increased risk of infection with human immunodeficiency virus (HIV)-1. HIV-1 infection in turn can lead to HIV-associated neurological disorders (HAND) that range from mild cognitive and motor impairment to HIV-associated dementia (HAD). Interestingly, post mortem brain specimens from HAD patients and transgenic (tg) mice expressing the viral envelope protein gp120 in the central nervous system display similar neuropathological signs. In HIV patients, the use of Methamphetamine appears to aggravate neurocognitive alterations. In the present study, we injected HIV/gp120tg mice and non-transgenic littermate control animals with Methamphetamine dissolved in Saline or Saline vehicle and assessed locomotion and stereotyped behaviour. We found that HIVgp120-transgenic mice differ significantly from non-transgenic controls in certain domains of their behavioural response to Methamphetamine. Thus this experimental model system may be useful to further study the mechanistic interaction of both the viral envelope protein and the psychostimulant drug in behavioural alterations and neurodegenerative disease.

Human immunodeficiency virus protease inhibitors and risk for peripheral neuropathy.

OBJECTIVE: Two recent analyses found that exposure to protease inhibitors (PIs) in the context of antiretroviral (ARV) therapy increased the risk for distal sensory polyneuropathy (DSPN) in subjects with human immunodeficiency virus (HIV) infection. These findings were supported by an in vitro model in which PI exposure produced neurite retraction and process loss in dorsal root ganglion sensory neurons. Confirmation of peripheral nerve toxicity with PIs could substantially limit their long-term use in highly active ARV therapy. METHODS: We evaluated current and past exposure to PIs as a risk factor for DSPN in 1,159 HIV-infected individuals enrolled in a large, prospective, observational, multicenter study. Signs of DSPN were ascertained by neurological examination. Subjects were grouped into categories according to past and current exposure to any ARV and to PIs. We included disease indicators such as nadir CD4, plasma viral load, and duration of HIV infection, as well as advancing age and exposure to dideoxynucleoside ARVs in multivariate models. RESULTS: In univariate analyses, both past and current PI exposure significantly increased the risk for DSPN. However, after adjusting for previously validated concomitant risk factors in multivariate models, none of the PI exposure groups was more likely to have DSPN than ARV naive subjects. A secondary evaluation of duration of PI use and exposure to individual PI drugs was similarly nonsignificant in multivariate models, except for small effects of amprenavir and lopinavir. INTERPRETATION: Evaluation of concomitant risks for HIV DSPN suggests that the independent risk attributable to PIs, if any, is small. This risk must be weighed against the important role of PIs in modern ARV therapy regimens.

Neurobehavioral effects of human immunodeficiency virus infection among former plasma donors in rural China.

The human immunodeficiency virus (HIV) epidemic in China has expanded rapidly in recent years, but little is known about the prevalence and features of HIV-associated neurocognitive disorders (HANDs) in this part of the world. We administered a comprehensive Western neuropsychological (NP) test battery to 203 HIV+ and 198 HIV- former plasma donors in the rural area of Anhui province. They found that 26% of the HIV- samples, and 46% of the HIV+ samples, were infected with hepatitis C virus (HCV), which can also have central nervous system (CNS) effects. To classify NP impairment, we developed demographically corrected test norms based upon individuals free of both infections (N=141). Using a global summary score, NP impairment was found in 34.2% of the HIV-monoinfected group and 39.7% of the coinfected group, as compared to 12.7% of the uninfected controls (P<.001). HIV+ participants with acquired immunodeficiency syndrome (AIDS) were more likely to be impaired (43%) than non-AIDS individuals (29%; P<.05). Lastly, when all infection groups were combined, participants with NP impairment reported more cognitive complaints (P<.01) and increased dependence in everyday functioning (P=.01). In sum, NP impairment in this large rural Chinese sample was associated with both HIV and HCV infections, and the impairment's prevalence, severity, and pattern were similar to those reported by Western studies. Clinical significance of NP impairment in this population is suggested by the participants' reports of reduced everyday functioning. These findings indicate that HAND is likely to be an important feature of HIV infection in developing countries, underscoring the need for international efforts to develop CNS-relevant treatments.

Long-term survival and serious cardiovascular events in HIV-infected patients treated with highly active antiretroviral therapy.

There is continuing interest in the longer term effects of highly active antiretroviral therapy (HAART) on the risk of cardiopulmonary events. We assessed this using updated administrative data from an open retrospective cohort of HIV-infected persons receiving care from the US Veterans Affairs (VA). Information on 41,213 HIV-infected patients receiving VA care between January 1993 and December 2003 was included. Patients were followed for an average of 4 years or 168,213 person-years of follow-up. The death rate fell from 20.9 deaths per 100 patient-years of observation in 1995 to 5.2 deaths per 100 patient-years in 2003. In patient-level analysis, adjusted hazard ratios for death dropped precipitously for all races to a low of 0.18 (95% confidence interval: 0.15 to 0.23) at 72 months of exposure to HAART. Hazards for serious cardiovascular events remained near 1.0 for exposure to HAART, and hazards for serious cardiovascular events, stroke, or death were only slightly higher than for death alone. No selection effects or secular trends were found. The benefits of HAART continued to increase in the 8 years after introduction and with 6 years of individual use. The risk of serious cardiovascular events should be factored into individual patient management but does not pose an important public health risk.

Neurobehavioral effects of HIV-1 infection in China and the United States: a pilot study.

The HIV epidemic in China has been increasing exponentially, yet there have been no studies of the neurobehavioral effects of HIV infection in that country. Most neuroAIDS research has been conducted in Western countries using Western neuropsychological (NP) methods, and it is unclear whether these testing methods are appropriate for use in China. Twenty-eight HIV seropositive (HIV+) and twenty-three HIV seronegative (HIV-) individuals with comparable gender, age, and education distributions were recruited in Beijing and the rural Anhui province in China. Thirty-nine HIV+ and thirty-one HIV- individuals were selected from a larger U.S. cohort recruited at the HIV Neurobehavioral Research Center, in San Diego, to be matched to the Chinese sample for age, disease status, and treatment variables. The NP test battery used with the U.S. and China cohorts included instruments widely used to study HIV infection in the United States. It consisted of 14 individual test measures, each assigned to one of seven ability areas thought to be especially vulnerable to effects of HIV on the brain (i.e., verbal fluency, abstraction/executive function, speed of information processing, working memory, learning, delayed recall, and motor function). To explore the cross-cultural equivalence and validity of the NP measures, we compared our Chinese and U.S. samples on the individual tests, as well as mean scaled scores for the total battery and seven ability domains. On each NP test measure, the mean of the Chinese HIV+ group was worse than that of the HIV- group. A series of 2x2 analyses of variance involving HIV+ and HIV- groups from both countries revealed highly significant HIV effects on the Global and all Domain mean scaled scores. Country effects appeared on two of the individual ability areas, at least partly due to education differences between the two countries. Importantly, the absence of HIV-by-Country interactions suggests that the NP effects of HIV are similar in the two countries. The NP test battery that was chosen and adapted for use in this study of HIV in China appears to have good cross-cultural equivalence, but appropriate Chinese norms will be needed to identify disease-related impairment in individual Chinese people. To inform the development of such norms, a much larger study of demographic effects will be needed, especially considering the wide range of education in that country.

Cardiovascular and cerebrovascular events in patients treated for human immunodeficiency virus infection.

BACKGROUND: Metabolic abnormalities associated with human immunodeficiency virus (HIV) infection, including dysglycemia and hyperlipidemia, are increasingly prevalent, and there is concern about the possibility of an association with accelerated cardiovascular and cerebrovascular disease. METHODS: We conducted a retrospective study of the risk of cardiovascular and cerebrovascular disease among the 36,766 patients who received care for HIV infection at Veterans Affairs facilities between January 1993 and June 2001. RESULTS: For antiretroviral therapy, 70.2 percent of the patients received nucleoside analogues, 41.6 percent received protease inhibitors, and 25.6 percent received nonnucleoside reverse-transcriptase inhibitors for a median of 17 months, 16 months, and 9 months, respectively. Approximately 1000 patients received combination therapy with a protease inhibitor for at least 48 months, and approximately 1000 patients received combination therapy with a nonnucleoside reverse-transcriptase inhibitor for at least 24 months. Between 1995 and 2001, the rate of admissions for cardiovascular or cerebrovascular disease decreased from 1.7 to 0.9 per 100 patient-years, and the rate of death from any cause decreased from 21.3 to 5.0 deaths per 100 patient-years. Patient-level regression analyses indicated that there was no relation between the use of nucleoside analogues, protease inhibitors, or nonnucleoside reverse-transcriptase inhibitors and the hazard of cardiovascular or cerebrovascular events, but the use of antiretroviral drugs was associated with a decreased hazard of death from any cause. CONCLUSIONS: Use of newer therapies for HIV was associated with a large benefit in terms of mortality that was not diminished by any increase in the rate of cardiovascular or cerebrovascular events or related mortality. Fear of accelerated vascular disease need not compromise antiretroviral therapy over the short term. However, prolonged survival among HIV infected patients means that longer-term observation and analysis are required.

Clean indoor air: advances in California, 1990-1999.

OBJECTIVES: This study assessed progress in achieving clean indoor air in California. METHODS: Data were from large, cross-sectional population-based surveys (1990-1999). RESULTS: Indoor workers reporting smoke-free workplaces increased from 35.0% (95% confidence interval [CI] = 33.7, 36.3) in 1990 to 93.4% (95% CI = 92.6, 94.2) in 1999. Exposure of nonsmoking indoor workers to secondhand tobacco smoke decreased from 29.0% (95% CI = 27.2, 30.8) to 15.6% (95% CI = 14.1, 17.1). Adults with smoke-free homes increased from 37.6 % (95% CI = 35.1, 40.1) in 1992 to 73.7% (95% CI = 73.2, 74.2) in 1999; nearly half of smokers in 1999 had smoke-free homes. In 1999, 82.2% (95% CI = 81.5, 82.9) of children and adolescents (0-17 years) had smoke-free homes, up from 38.0% (95% CI = 35.1, 40.9) in 1992. CONCLUSIONS: California's advances highlight an important opportunity for tobacco control.