Descriptive epidemiology of total joint replacement procedures is limited to annual procedure volumes (incidence). The prevalence of the growing number of individuals living with a total hip or total ...knee replacement is currently unknown. Our objective was to estimate the prevalence of total hip and total knee replacement in the United States.
Prevalence was estimated using the counting method by combining historical incidence data from the National Hospital Discharge Survey and the Healthcare Cost and Utilization Project (HCUP) State Inpatient Databases from 1969 to 2010 with general population census and mortality counts. We accounted for relative differences in mortality rates between those who have had total hip or knee replacement and the general population.
The 2010 prevalence of total hip and total knee replacement in the total U.S. population was 0.83% and 1.52%, respectively. Prevalence was higher among women than among men and increased with age, reaching 5.26% for total hip replacement and 10.38% for total knee replacement at eighty years. These estimates corresponded to 2.5 million individuals (1.4 million women and 1.1 million men) with total hip replacement and 4.7 million individuals (3.0 million women and 1.7 million men) with total knee replacement in 2010. Secular trends indicated a substantial rise in prevalence over time and a shift to younger ages.
Around 7 million Americans are living with a hip or knee replacement, and consequently, in most cases, are mobile, despite advanced arthritis. These numbers underscore the substantial public health impact of total hip and knee arthroplasties.
Abstract Background The utilization of hip arthroscopy continues to increase in the United States. The purpose of this study was to examine trends in hip arthroscopy procedures and outcomes. Methods ...We performed a retrospective cohort study using Optum Labs Data Warehouse administrative claims data. The cohort comprised 10,042 privately insured enrollees aged 18-64 years who underwent a hip arthroscopy procedure between 2005 and 2013. Utilization trends were examined using age-, sex- and calendar-year specific hip arthroscopy rates. Outcomes were examined using the survival analysis methods and included subsequent hip arthroscopy and total hip arthroplasty. Results Hip arthroscopy rates increased significantly over time from 3.6 per 100,000 in 2005 to 16.7 per 100,000 in 2013. The overall 2-year cumulative incidence of subsequent hip arthroscopy and total hip arthroplasty were 11% and 10%, respectively. In the subset of patients in whom laterality of the subsequent procedure could be determined, about half of the subsequent hip arthroscopy procedures (46%) and almost all of the THA procedures (94%) were on the same side. Decreasing age was significantly associated with the risk of subsequent arthroscopy (p<0.01), whereas increasing age was significantly associated with the subsequent risk of total hip arthroplasty (p<0.01). The 5-year cumulative incidence of total hip arthroplasty reached as high as 35% among individuals aged 55-64 years. Conclusion The utilization of hip arthroscopy procedures increased dramatically over the last decade in the 18-64 year old privately insured population, with the largest increase in younger age groups. Future studies are warranted to understand the determinants of the large increase in utilization of hip arthroscopy and outcomes.
Background Although psoriasis is considered to have a dual peak in age of onset, currently no studies exist regarding the incidence of psoriasis in children. Objective The objective of this study was ...to determine the incidence of psoriasis in childhood. Methods A population-based incidence cohort of patients aged younger than 18 years first given the diagnosis of psoriasis between January 1, 1970, and December 31, 1999, was assembled. The complete medical record of each child was reviewed and psoriasis diagnosis was validated by a confirmatory diagnosis in the medical record by a dermatologist or medical record review by a dermatologist. Age- and sex-specific incidence rates were calculated and were age and sex adjusted to 2000 US white population. Results The overall age- and sex-adjusted annual incidence of pediatric psoriasis was 40.8 per 100,000 (95% confidence interval: 36.6-45.1). When psoriasis diagnosis was restricted to dermatologist-confirmed subjects in the medical record, the incidence was 33.2 per 100,000 (95% confidence interval: 29.3-37.0). Incidence of psoriasis in children increased significantly over time from 29.6 per 100,000 in 1970 through 1974 to 62.7 per 100,000 in 1995 through 1999 ( P < .001). Chronic plaque psoriasis was the most common type (73.7%), and the most commonly involved sites were the extremities (59.9%) and the scalp (46.8%). Limitations The population studied was a mostly white population in the upper Midwest. Conclusion The incidence of pediatric psoriasis increases with increasing age. There is no apparent dual peak in incidence. The incidence of pediatric psoriasis increased in recent years in both boys and girls.
Background:
The incidence of isolated anterior cruciate ligament (ACL) tears in the general population is not well defined.
Purpose/Hypothesis:
The purpose of this study was to define the ...population-based incidence of ACL tears, describe trends in ACL injuries over time, and evaluate changes in the rate of surgical management. The hypothesis was that the incidence of ACL injury and the rate of subsequent ACL reconstruction increase over time.
Study Design:
Cohort study; Level of evidence, 3.
Methods:
The study population included 1841 individuals who were diagnosed with new-onset, isolated ACL tears (without concomitant ligament injury that required surgery) between January 1, 1990, and December 31, 2010. The complete medical records were reviewed to confirm diagnosis and to extract injury and treatment details. Age- and sex-specific incidence rates were calculated and adjusted to the 2010 US population. Poisson regression analyses were performed to examine incidence trends by age, sex, and calendar period.
Results:
The overall age- and sex-adjusted annual incidence of ACL tears was 68.6 per 100,000 person-years. Incidence was significantly higher in male patients than in females (81.7 vs 55.3 per 100,000, P < .001). The incidence of isolated ACL tears decreased significantly over time in males (P < .001) but remained relatively stable in females. Age-specific patterns differed in male and female patients, with a peak in incidence (241.0 per 100,000) between 19 and 25 years in males and a peak in incidence (227.6 per 100,000) between 14 and 18 years in females. The rate of ACL reconstruction increased significantly over time in all age groups (P < .001).
Conclusion:
With an annual incidence of 68.6 per 100,000 person-years, isolated ACL tears remain a common orthopaedic injury. Differences in age-specific incidence trends in male and female patients may potentially reflect differences in sports participation patterns through the high school and college years. The significant increase in the rate of ACL reconstruction over time may reflect changing surgical indications or an increasing desire among patients to return to high levels of activity after ACL injury.
To examine the impact of systemic inflammation and serum lipids on cardiovascular disease (CVD) in rheumatoid arthritis (RA).
In a population-based RA incident cohort (1987 American College of ...Rheumatology criteria first met between 1988 and 2007), details were collected of serum lipid measures, erythrocyte sedimentation rates (ESRs), C-reactive protein (CRP) measures and cardiovascular events, including ischaemic heart disease and heart failure. Cox models were used to examine the association of lipids and inflammation with the risk of CVD and mortality, adjusting for age, sex and year of RA incidence.
The study included 651 patients with RA (mean age 55.8 years, 69% female); 67% were rheumatoid factor positive. ESR was associated with the risk of CVD (HR=1.2 per 10 mm/h increase, 95% CI 1.1 to 1.3). Similar findings, although not statistically significant, were seen with CRP (p=0.07). A significant non-linear association for total cholesterol (TCh) with risk of CVD was found, with 3.3-fold increased risk for TCh <4 mmol/l (95% CI 1.5 to 7.2) and no increased risk of CVD for TCh ≥4 mmol/l (p=0.57). Low low-density lipoprotein cholesterol (LDL <2 mmol/l) was associated with marginally increased risk of CVD (p=0.10); there was no increased risk for LDL ≥2 mmol/l (p=0.76).
Inflammatory measures (particularly, ESR) are significantly associated with the risk of CVD in RA. Lipids may have paradoxical associations with the risk of CVD in RA, whereby lower TCh and LDL levels are associated with increased cardiovascular risk.
Objective
To determine the incidence of psoriatic arthritis (PsA) in a US population and describe trends in incidence and mortality over 5 decades.
Methods
The previously identified population‐based ...cohort that included Olmsted County, Minnesota residents ≥18 years of age who fulfilled PsA criteria during 1970–1999 was extended to include patients with incident PsA during 2000–2017. Age‐ and sex‐specific incidence rates and point prevalence, adjusted to the 2010 US White population, were reported.
Results
There were 164 incident cases of PsA in 2000–2017 (mean ± SD age 46.4 ± 12.0 years; 47% female). The overall age‐ and sex‐adjusted annual incidence of PsA per 100,000 population was 8.5 (95% confidence interval 95% CI 7.2–9.8) and was higher in men (9.3 95% CI 7.4–11.3) than women (7.7 95% CI 5.9–9.4) in 2000–2017. Overall incidence was highest in the 40–59 years age group. The incidence rate was relatively stable during 2000–2017, with no evidence of an overall increase or an increase in men only (but a modest increase of 3% per year in women), compared to 1970–1999 when a 4%‐per‐year increase in incidence was observed. Point prevalence was 181.8 per 100,000 population (95% CI 156.5–207.1) in 2015. The percentage of women among those with PsA increased from 39% in 1970–1999 and 41% in 2000–2009 to 54% in 2010–2017 (P = 0.08). Overall survival in PsA did not differ from the general population (standardized mortality ratio 0.85 95% CI 0.61–1.15).
Conclusion
The incidence of PsA in this predominantly White US population was stable in 2000–2017, in contrast to previous years. However, an increasing proportion of women with PsA was found in this study.
Background
The number of obese patients undergoing THA is increasing. Previous studies have shown that obesity is associated with an increased likelihood of complications after THA, but there is ...little information regarding the impact of obesity on medical resource use and direct medical costs in THA.
Questions/purposes
We sought to examine the relationship between obesity, length of stay, and direct medical costs in a large cohort of patients undergoing THAs.
Methods
The study included 8973 patients who had undergone 6410 primary and 2563 revision THAs at a large US medical center between January 1, 2000, and September 31, 2008. Patients with bilateral procedures within 90 days after index admission and patients with acute trauma were excluded. Data regarding clinical, surgical characteristics, and complications were obtained from the original medical records and the institutional joint registry. Patients were classified into eight groups based on their BMI at the time of surgery. Direct medical costs were calculated by using standardized, inflation-adjusted costs for services and procedures billed during hospitalization and the 90-day window. Study end points were hospital length of stay, direct medical costs during hospitalization, and the 90-day window. End points were compared across the eight BMI categories in multivariable risk-adjusted linear regression models.
Results
Mean length of stay and the direct medical costs were lowest for patients with a BMI of 25 to 35 kg/m
2
. Increasing BMI was associated with longer hospital stays and costs. Every five-unit increase in BMI beyond 30 kg/m
2
was associated with approximately USD $500 higher hospital costs and USD $900 higher 90-day costs in primary THA (p = 0.0001), which corresponded to 5% higher costs. The cost increase associated with BMI was greater in the revision THA cohort where every five-unit increase in BMI beyond 30 kg/m
2
was associated with approximately USD $800 higher hospital costs and USD $1500 higher 90-day costs. These estimates remained unchanged after adjusting for comorbidities or complications.
Conclusions
Obesity is associated with longer hospital stays and higher costs in THA. The significant effect of obesity on costs persists even among patients without comorbidities but the increased costs associated with obesity may be balanced by the potential benefits of THA in the obese. Increasing prevalence of obesity likely contributes to the increasing financial burden of THA worldwide.
Level of Evidence
Level IV, economic and decision analyses. See the Instructions for Authors for a complete description of levels of evidence.
Natural language processing (NLP) methods have the capability to process clinical free text in electronic health records, decreasing the need for costly manual chart review, and improving data ...quality. We developed rule-based NLP algorithms to automatically extract surgery specific data elements from knee arthroplasty operative notes.
Within a cohort of 20,000 knee arthroplasty operative notes from 2000 to 2017 at a large tertiary institution, we randomly selected independent pairs of training and test sets to develop and evaluate NLP algorithms to detect five major data elements. The size of the training and test datasets were similar and ranged between 420 to 1592 surgeries. Expert rules using keywords in operative notes were used to implement NLP algorithms capturing: (1) category of surgery (total knee arthroplasty, unicompartmental knee arthroplasty, patellofemoral arthroplasty), (2) laterality of surgery, (3) constraint type, (4) presence of patellar resurfacing, and (5) implant model (catalog numbers). We used institutional registry data as our gold standard to evaluate the NLP algorithms.
NLP algorithms to detect the category of surgery, laterality, constraint, and patellar resurfacing achieved 98.3%, 99.5%, 99.2%, and 99.4% accuracy on test datasets, respectively. The implant model algorithm achieved an F1-score (harmonic mean of precision and recall) of 99.9%.
NLP algorithms are a promising alternative to costly manual chart review to automate the extraction of embedded information within knee arthroplasty operative notes. Further validation in other hospital settings will enhance widespread implementation and efficiency in data capture for research and clinical purposes.
Level III.
Abstract Diabetes mellitus is an established risk factor for infections but evidence is conflicting to what extent perioperative hyperglycemia, glycemic control and treatment around the time of ...surgery modify the risk of prosthetic joint infections (PJIs). In a cohort of 20,171 total hip and knee arthroplasty procedures, we observed a significantly higher risk of PJIs among patients with a diagnosis of diabetes mellitus (hazard ratio HR 1.55, 95% CI 1.11, 2.16), patients using diabetes medications (HR 1.56, 95% CI 1.08, 2.25) and patients with perioperative hyperglycemia (HR 1.59, 95% CI 1.07, 2.35), but the effects were attenuated after adjusting for body mass index, type of surgery, ASA score and operative time. Although data were limited, there was no association between hemoglobin A1c values and PJIs.