Traumatic Brain Injury and Risk of Alzheimer's Disease and Related Dementias in the Population.

BACKGROUND: Epidemiological studies examining associations between traumatic brain injury (TBI) and Alzheimer's disease and related dementias (ADRD) have yielded conflicting results, which may be due to methodological differences. OBJECTIVE: To examine the relationship between the presence and severity of TBI and risk of ADRD using a population-based cohort with medical record abstraction for confirmation of TBI and ADRD. METHODS: All TBI events among Olmsted County, Minnesota residents aged > 40 years from 1985-1999 were confirmed by manual review and classified by severity. Each TBI case was randomly matched to two age-, sex-, and non-head injury population-based referents without TBI. For TBI events with non-head trauma, the Trauma Mortality Prediction Model was applied to assign an overall measure of non-head injury severity and corresponding referents were matched on this variable. Medical records were manually abstracted to confirm ADRD diagnosis. Cox proportional hazards models examined the relationship between TBI and severity with risk of ADRD. RESULTS: A total of 1,418 residents had a confirmed TBI (865 Possible, 450 Probable, and 103 Definite) and were matched to 2,836 referents. When combining all TBI severities, the risk of any ADRD was significantly higher for those with a confirmed TBI compared to referents (HR = 1.32, 95% CI: 1.11, 1.58). Stratifying by TBI severity, Probable (HR = 1.42, 95% CI: 1.05, 1.92) and Possible (HR = 1.29, 95% CI: 1.02-1.62) TBI was associated with an increased risk of ADRD, but not Definite TBI (HR = 1.22, 95% CI: 0.68, 2.18). CONCLUSION: Our analyses support including TBI as a potential risk factor for developing ADRD.

Long-Term Risk of Stroke after Traumatic Brain Injury: A Population-Based Medical Record Review Study.

OBJECTIVE: To reliably inform secondary prevention strategies and reduce morbidity and mortality after traumatic brain injury (TBI), we sought to understand the long-term risk of stroke after TBI in patients aged 40 years and older in comparison to age- and sex-matched referents from a population-based cohort. MATERIALS AND METHODS: TBI cases in Olmsted County, Minnesota from January 1, 1985, to December 31, 1999, were confirmed by manual review, classified by injury severity and mechanism, and nonhead trauma was quantified. Each TBI case was matched to 2 sex- and age-matched population-based referents without TBI and with similar severity nonhead trauma. Records of cases and referents were manually abstracted to confirm stroke diagnosis. Stroke events during initial hospitalization for TBI were excluded. RESULTS: In total, 1,410 TBI cases were confirmed, 61% classified as possible TBI (least severe, consistent with concussive), with the most common mechanism being falls. There were 162 stroke events among those with TBI (11.5%) and 269 among referents (9.5%). Median time to stroke from the index date for those with TBI was 10.2 years (Q1-Q3 5.2-17.8), and for referents 12.1 years (Q1-Q3 6.2-17.3), p = 0.215. All-severity TBI was associated with increased risk of stroke (HR: 1.32, 95% CI: 1.06-1.63, p = 0.011), but only definite TBI (consistent with moderate-severe) was associated with significant risk (HR: 2.20, 95% CI: 1.04-4.64, p = 0.038) when stratified by severity. DISCUSSION/CONCLUSION: By confirming TBI cases, stroke diagnoses, and injury severity classification using manual review with levels of accuracy not previously reported, these results indicate moderate-severe TBI increases long-term risk for stroke. These findings confirm the need to regularly assess long-term vascular risk after TBI to implement disease prevention strategies.

CONNECT: A pragmatic clinical trial testing a remotely provided linkage to service coordination after hospitalization for TBI.

OBJECTIVE: To test whether a complex behavioral intervention delivered remotely to connect individuals to clinical resources after hospitalization for TBI improved their quality of life. DESIGN/METHODS: Community-based randomized pragmatic clinical trial. Main measures TBI-QOL, Activity Measure for Post-Acute Care (AM-PAC), Clinical Satisfaction and Competency Rating Scale. RESULTS: 332 individuals ≥18 years-old hospitalized for TBI in four upper Midwest states were randomized to Remote (n = 166) and Usual Care (n = 166) groups. The groups were equivalent and representative of their state population's racial and ethnic composition, age, and proportion living in rural communities. There were no significant differences within or between experimental groups over the study period in TBI-QOL t-scores. There was a significant improvement in AM-PAC Daily Activities within the Remote group and a significant between-group improvement in clinical satisfaction for the Remote group. CONCLUSION: Enrolling a representative, regional community-based sample of individuals with TBI can be successful, and delivering a customized complex behavioral intervention remotely is feasible. The overall lack of intervention effectiveness was likely due to enrolling individuals without pre-identified clinical needs, initiating intervention after the immediate post-acute phase when needs are often highest, inability to provide direct clinical care remotely, and potential lack of outcome measure responsiveness in our sample.

Cause of Death after Traumatic Brain Injury: A Population-Based Health Record Review Analysis Referenced for Nonhead Trauma.

INTRODUCTION: Traumatic brain injury (TBI) is a leading cause of disability and is associated with decreased survival. Although it is generally accepted that TBI increases risk of death in acute and postacute periods after injury, causes of premature death after TBI in the long term are less clear. METHODS: A cohort sample of Olmsted County, Minnesota, residents with confirmed TBI from January 1987 through December 1999 was identified. Each case was assigned an age- and sex-matched non-TBI referent case, called regular referent. Confirmed TBI cases with simultaneous nonhead injuries were identified, labeled special cases. These were assigned 2 age- and sex-matched special referents with nonhead injuries of similar severity. Underlying causes of death in each case were categorized using death certificates, International Classification of Diseases, Ninth Revision, International Statistical Classification of Diseases, Tenth Revision, and manual health record review. Comparisons were made over the study period and among 6-month survivors. RESULTS: Case-regular referent pairs (n = 1,257) were identified over the study period, and 221 were special cases. In total, 237 deaths occurred among these pairs. A statistically significant difference was observed between total number of deaths among all cases (n = 139, 11%) and regular referents (n = 98, 8%) (p = 0.006) over the entire period. This outcome was not true for special cases (32/221, 14%) and special referents (61/441, 14%) (p = 0.81). A greater proportion of deaths by external cause than all other causes was observed in all cases (52/139, 37%) versus regular referents (3/98, 3%) and in special cases (13/32, 41%) versus special referents (5/61, 8%) (p < 0.001 for both). Among all case-referent pairs surviving 6 months, no difference was found between total number of deaths (p = 0.82). The underlying cause of death between these 2 groups was significantly different for external causes only (p < 0.01). For special cases surviving 6 months versus special referents, no difference was observed in total number of deaths (p = 0.24) or underlying causes of death (p = 1.00) between groups. DISCUSSION/CONCLUSION: This population-based case-matched referent study showed that increased risk of death after TBI existed only during the first 6 months after injury, and the difference was due to external causes.

Direct Inpatient Medical Costs of Operative Treatment of Periprosthetic Hip and Knee Infections Are Twofold Higher Than Those of Aseptic Revisions.

BACKGROUND: Periprosthetic joint infections (PJIs) following total hip arthroplasty (THA) and total knee arthroplasty (TKA) are associated with substantial morbidity. A better understanding of the costs of PJI treatment can inform prevention, treatment, and reimbursement strategies. The purpose of the present study was to describe direct inpatient medical costs associated with the treatment of hip and knee PJI. METHODS: At a single tertiary care institution, 176 hips and 266 knees that underwent 2-stage revisions for the treatment of PJI from 2009 to 2015 were compared with 1,611 hips and 1,276 knees that underwent revisions for aseptic indications. In addition, 84 hips and 137 knees that underwent irrigation and debridement (I&D) with partial component exchange were compared with 39 hips and 138 knees that underwent partial component exchange for aseptic indications. Line-item details of services billed during hospitalization were retrieved, and standardized direct medical costs were calculated in 2018 inflation-adjusted dollars. RESULTS: The mean direct medical cost of 2-stage revision THA performed for the treatment of PJI was significantly higher than that of aseptic revision THA ($58,369 compared with $22,846, p < 0.001). Similarly, the cost of 2-stage revision TKA performed for the treatment of PJI was significantly higher than that of aseptic revision TKA ($56,900 compared with $24,630, p < 0.001). Even when the total costs of aseptic revisions were doubled for a representative comparison with 2-stage procedures, the costs of PJI procedures were 15% to 28% higher than those of the doubled costs of aseptic revisions (p < 0.001). The mean direct medical cost of I&D procedures for PJI was about twofold higher than of partial component exchange for aseptic indications. CONCLUSIONS: The direct medical costs of operative treatment of PJI following THA and TKA are twofold higher than the costs of similar aseptic revisions. The high economic burden of PJI warrants efforts to reduce the incidence of PJI. Reimbursement schemes should account for the high costs of treating PJI in order to ensure sustainable patient care. LEVEL OF EVIDENCE: Economic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Revision Total Hip Arthroplasty for the Treatment of Fracture: More Expensive, More Complications, Same Diagnosis-Related Groups: A Local and National Cohort Study.

BACKGROUND: Revision total hip arthroplasty (revision THA) occurs for a wide variety of indications and in the United States it is coded under Diagnosis-Related Groups (DRGs) 466, 467, and 468, which do not account for revision etiology, a potentially substantial driver of cost. This study investigates revision THA costs and 30-day complications by indication, both locally and nationally. METHODS: Hospitalization costs and complication rates for 1,422 aseptic revision THAs performed at a high-volume center between 2009 and 2014 were retrospectively reviewed. Additionally, charges for 28,133 revision THAs in the National Inpatient Sample (NIS) were converted to costs using the Healthcare Cost and Utilization Project cost-to-charge ratios, and 30-day complication rates for 3,224 revision THAs were obtained with use of the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP). Costs and complications were compared between revision THAs performed for fracture, wear/loosening, and dislocation/instability with use of simultaneous and pairwise comparisons and a multivariable model accounting for American Society of Anesthesiologists (ASA) score, age, and sex. RESULTS: Local hospitalization costs for fracture (median, $25,672) were significantly higher than those for wear/loosening ($20,228; p < 0.001) or dislocation/instability ($17,911; p < 0.001), with differences remaining significant even after adjusting for patient comorbidities (p < 0.001). NIS costs for fracture (median, $27,596) were higher than those for other aseptic indications (wear/loosening: $21,176, p < 0.001; dislocation/instability: $16,891, p< 0.001). Local 30-day orthopaedic complication rates for fracture (20.7%) were higher those than for dislocation/instability (9.0%; p = 0.007) and similar to those for wear/loosening (17.6%; p = 0.434). Nationally, combined medical and surgical complication rates for fracture (71.3% of patients with ≥1 complication) were significantly higher than those for wear/loosening (35.2%; p < 0.001) or dislocation/instability (35.1%; p < 0.001). CONCLUSIONS: Hospitalization costs for revision THA for fracture were 33% to 48% higher than for all other aseptic revision THAs, both locally and nationally. This increased cost persisted even after multivariable comorbidity adjustment, the current DRG basis for stratifying revision THA reimbursement. Additionally, 30-day complication rates suggest that increased resource utilization for fracture patients continues even after discharge. Indication-specific coding and reimbursement systems are necessary to maintain sustainable access to revision THA for all patients. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Mortality After Periprosthetic Femur Fractures During and After Primary and Revision Total Hip Arthroplasty.

INTRODUCTION: We determined mortality rates after intraoperative and postoperative periprosthetic femur fractures in primary and revision total hip arthroplasty (THA). METHODS: The study population comprised 522 intraoperative and 480 postoperative femur fractures in 26,250 primary THA patients and 590 intraoperative and 224 postoperative femur fractures in 4,532 revision THA patients. The risk of death was examined using Cox regression models. RESULTS: In primary THA, intraoperative periprosthetic femur fractures were not associated with excess risk of death (hazard ratio, 1.03; 95% confidence interval, 0.86 to 1.22). The risk of death was slightly elevated among primary THA patients with postoperative femur fractures (hazard ratio, 1.19; 95% confidence interval, 1.08 to 1.43), but the excess risk was only confined to patients with comorbid orthopaedic conditions. In revision THA, neither intraoperative nor postoperative periprosthetic femur fractures were associated with excess risk of death. CONCLUSION: Periprosthetic femur fractures are not associated with excess mortality among primary osteoarthritis patients. LEVEL OF EVIDENCE: Level III.

Long-term Mortality After Revision THA.

BACKGROUND: Long-term mortality after primary THA is lower than in the general population, but it is unknown whether this is also true after revision THA. QUESTIONS/PURPOSES: We examined (1) long-term mortality according to reasons for revision after revision THA, and (2) relative mortality trends by age at surgery, years since surgery, and calendar year of surgery. METHODS: This retrospective study included 5417 revision THAs performed in 4532 patients at a tertiary center between 1969 and 2011. Revision THAs were grouped by surgical indication in three categories: periprosthetic joint infections (938; 17%); fractures (646; 12%); and loosening, bearing wear, or dislocation (3833; 71%). Patients were followed up until death or December 31, 2016. The observed number of deaths in the revision THA cohort was compared with the expected number of deaths using standardized mortality ratios (SMRs) and Poisson regression models. The expected number of deaths was calculated assuming that the study cohort had the same calendar year, age, and sex-specific mortality rates as the United States general population. RESULTS: The overall age- and sex-adjusted mortality was slightly higher than the general population mortality (SMR, 1.09; 95% CI, 1.05-1.13; p < 0.001). There were significant differences across the three surgical indication subgroups. Compared with the general population mortality, patients who underwent revision THA for infection (SMR, 1.35; 95% CI, 1.24-1.48; p < 0.001) and fractures (SMR, 1.23; 95% CI, 1.11-1.37; p < 0.001) had significantly increased risk of death. Patients who underwent revision THA for aseptic loosening, wear, or dislocation had a mortality risk similar to that of the general population (SMR, 1.01; 95% CI, 0.96-1.06; p = 0.647). The relative mortality risk was highest in younger patients and declined with increasing age at surgery. Although the relative mortality risk among patients with aseptic indications was lower than that of the general population during the first year of surgery, the risk increased with time and got worse than that of the general population after approximately 8 to 10 years after surgery. Relative mortality risk improved with time after revision THA for aseptic loosening, wear, or dislocation. CONCLUSIONS: Shifting mortality patterns several years after surgery and the excess mortality after revision THA for periprosthetic joint infections and fractures reinforce the need for long-term followup, not only for implant survival but overall health of patients having THA. LEVEL OF EVIDENCE: Level III, therapeutic study.

Cost-Effectiveness of a Care Transitions Program in a Multimorbid Older Adult Cohort.

BACKGROUND/OBJECTIVES: Facing penalties for preventable 30-day hospital readmissions, many provider groups have implemented programs to remedy this problem, but the cost efficacy and value of such programs are not well delineated. The objective was to compare total cost of care over 30 days of individuals enrolled in the Mayo Clinic Care Transitions (MCCT) program and individuals not enrolled. DESIGN: Retrospective cohort study using secondary data analysis of a previously published cohort study. SETTING: Mayo Clinic, Rochester, Minnesota. PARTICIPANTS: MCCT participants (n = 363) and individuals in a propensity-matched referent cohort (n = 365). INTERVENTION: MCCT program enrollment. MEASUREMENTS: The primary outcome was total cost of care over 30 days after hospital discharge. A 2-part modeling strategy was used to analyze 30-day costs: whether individuals had non-zero costs during the 30 days after discharge and a generalized linear model for individuals who incurred costs. Potential heterogeneous effects of the MCCT program were examined according to decile of 30-day costs using quantile regression. RESULTS: Mean age was 83 in both groups. Adjusted mean 30-day cost after hospitalization was $3,363 (95% confidence interval (CI) = $2,512-4,213) in the MCCT group and $4,161 (95% CI = $3,096-5,226) in the control group (P = .25). Cost savings of $2,744 (P = .008) at the eighth decile and $3,388 (P = .20) at the ninth decile were demonstrated. Thus, the only statistically significant differences were in the post hoc subgroup analysis in the highest-cost subgroups. CONCLUSION: We did not find a difference in overall mean costs between the MCCT group and the control group, although intervention participants in the upper deciles of costs appeared to experience lower costs than controls. A larger study cohort might better determine the value of the intervention.

Nursing Home Use Across The Spectrum of Cognitive Decline: Merging Mayo Clinic Study of Aging With CMS MDS Assessments.

BACKGROUND/OBJECTIVES: Objective, complete estimates of nursing home (NH) use across the spectrum of cognitive decline are needed to help predict future care needs and inform economic models constructed to assess interventions to reduce care needs. DESIGN: Retrospective longitudinal study. SETTING: Olmsted County, MN. PARTICIPANTS: Mayo Clinic Study of Aging participants assessed as cognitively normal (CN), mild cognitive impairment (MCI), previously unrecognized dementia, or prevalent dementia (age = 70-89 years; N = 3,545). MEASUREMENTS: Participants were followed in Centers for Medicare and Medicaid Services (CMS) Minimum Data Set (MDS) NH records and in Rochester Epidemiology Project provider-linked medical records for 1-year after assessment of cognition for days of observation, NH use (yes/no), NH days, NH days/days of observation, and mortality. RESULTS: In the year after cognition was assessed, for persons categorized as CN, MCI, previously unrecognized dementia, and prevalent dementia respectively, the percentages who died were 1.0%, 2.6%, 4.2%, 21%; the percentages with any NH use were 3.8%, 8.7%, 19%, 40%; for persons with any NH use, median NH days were 27, 38, 120, 305, and median percentages of NH days/days of observation were 7.8%, 12%, 33%, 100%. The year after assessment, among persons with prevalent dementia and any NH use, >50% were a NH resident all days of observation. Pairwise comparisons revealed that each increase in cognitive impairment category exhibited significantly higher proportions with any NH use. One-year mortality was especially high for persons with prevalent dementia and any NH use (30% vs 13% for those with no NH use); 58% of all deaths among persons with prevalent dementia occurred while a NH resident. CONCLUSIONS: Findings suggest reductions in NH use could result from quality alternatives to NH admission, both among persons with MCI and persons with dementia, together with suitable options for end-of-life care among persons with prevalent dementia.

Comparison of the hospital costs for two-stage reimplantation for deep infection, single-stage revision and primary total elbow arthroplasty.

BACKGROUND: The purpose of the present study was to determine the cost of two-stage reimplantation for the treatment of deep infection after total elbow arthroplasty (TEA) and compare this with primary and aseptic revision TEA. METHODS: Three hundred and seventy-one primary TEA and 286 revision TEAs (including 47 elbows requiring two-stage reimplantation) were performed. Total direct medical costs during each hospitalization were obtained from our institutional research database and compared for three groups: primary TEA, revision for nonseptic reasons and two-stage reimplantation for deep infection. RESULTS: The mean cost of an uncomplicated primary TEA and aseptic revision TEA was $18,464 and $18,796, respectively. The mean overall cost associated with two-stage reimplantation increased to $34,286. Two-stage reimplantation increased both Part A (hospital costs) and Part B (professional costs). The mean Part A cost for septic revision TEA was $29,102 versus $15,844 for primary TEA. The mean Part B cost for septic revision TEA was $5,184 versus $2,621 for primary TEA. CONCLUSIONS: Two-stage reimplantation for treatment of an infected TEA costs 186% the hospital cost of a primary uncomplicated or aseptic revision TEA. The overall cost to society is even greater if we take into account the cost of antibiotic therapy in between stages and lost days from work.

The hospital cost of two-stage reimplantation for deep infection after shoulder arthroplasty.

BACKGROUND: The cost of treating infection after hip and knee arthroplasty is well documented in the literature. The purpose of this study was to determine the cost of two-stage reimplantation for deep infection after shoulder arthroplasty. METHODS: Between 2003 and 2012, 57 shoulders (56 patients) underwent a two-stage reimplantation for deep periprosthetic shoulder infection; implants placed at reimplantation included anatomic total shoulder arthroplasty (a-TSA) in 58%, reverse total shoulder arthroplasty (r-TSA) in 40%, and hemiarthroplasty (HA) in 2%. During the same timeframe, 2953 primary shoulder arthroplasties (2589 patients) were performed at the same institution (a-TSA in 55%, r-TSA in 28%, and HA in 17%). Total direct medical costs were calculated by using standardized, inflation-adjusted costs for services and procedures billed during hospitalization and were adjusted to nationally representative unit costs in 2013 inflation-adjusted dollars. RESULTS: The mean hospital cost (per shoulder) for two-stage reimplantation was $35,824 (95% CI: 33,363 to 38,285) and was significantly higher than for primary procedures (mean: $16,068; 95% CI: 15,823 to 16,314). Both Part A and Part B costs were significantly higher in two-stage reimplantation (p < 0.001). For part A (hospital services), the mean cost for two-stage reimplantation was $29,851 (95% CI: 27,741 to 31,960), compared to $13,508 (95% CI: 13,302 to 13,715) for primaries. For part B (professional costs), mean costs were $5973 (95% CI: 5493 to 6453) versus 2560 (95% CI: 2512 to 2608) respectively. CONCLUSIONS: The hospital cost of two-stage reimplantation for the treatment of an infected shoulder arthroplasty is about two times higher than the cost of a primary shoulder arthroplasty.

Economic and clinical impact of routine weekend catheterization services.

OBJECTIVES: To assess the impact of weekend cardiac catheterization (cath) services for nonemergent inpatients. STUDY DESIGN: Retrospective cohort study of patients undergoing cath before and after Saturday cath service availability (CSA). METHODS: Cohorts included Friday and Saturday admissions with cath (with or without revascularization) on the subsequent Monday from January 1, 2007, to December 31, 2008 (pre-CSA events), and Friday or Saturday admissions undergoing cath the subsequent or same Saturday from January 1, 2009, to December 31, 2010 (post-CSA events). Administrative and registry data provided demographics, comorbidities, percutaneous coronary intervention (PCI) details, adverse events, hospital length of stay (LOS), and inpatient expenditures. We used generalized linear modeling to predict LOS and costs, and logistic regression to estimate the likelihood of adverse events during follow-up. RESULTS: We identified 331 pre-CSA cases (327 patients) and 244 post-CSA cases (243 patients). Cohorts were similar in age (66 years), sex (59% male), and level of comorbidity. PCI use was higher following CSA (42% vs 26%; P <.001), with procedural success accomplished in 95% and 94% of pre- and post-CSA patients, respectively. Adjusted clinical outcomes were similar (odds ratio [OR] for in-hospital mortality, 0.67 post-CSA vs pre-CSA; P = .55; OR for 30-day revascularization, 1.14; P = .68). Models predict an average LOS reduction of 1.7 days following CSA (5.7 vs 4.0 days; P <.001) yet inpatient costs were similar ($24,817 vs $24,753; 95% CI of difference, -$3611 to $3576). CONCLUSIONS: Weekend CSA for routine inpatients was clinically safe and effective, and reduced hospital LOS. Similar inpatient costs likely reflect a shift in case mix in this nonrandomized study.

Health Care Utilization and Direct Medical Costs of Tennis Elbow: A Population-Based Study.

BACKGROUND: Tennis elbow is commonly encountered by physicians, yet little is known about the cost of treating this condition. HYPOTHESIS: The largest cost associated with treating tennis elbow is procedural intervention. STUDY DESIGN: Descriptive epidemiology study. LEVEL OF EVIDENCE: Level 4. METHODS: This retrospective population-based study reviewed patients who were treated for new-onset tennis elbow between January 1, 2003 and December 31, 2012. All patients were followed up through their medical and administrative records to identify health care encounters and interventions for tennis elbow. Unit costs for each health service/procedure were adjusted to nationally representative unit costs in 2013 inflation-adjusted dollars. RESULTS: In a cohort of 931 patients who had 2 or more clinical encounters for new-onset lateral epicondylosis during a 12-month period after initial diagnosis, 62% received a median of 3 physical therapy sessions (cost, $100/session) and 40% received a median of 1 steroid injection (cost, $82/injection). Only 4% of patients received surgical intervention with mean costs of $4000. The mean (median) total direct medical cost of services related to lateral epicondylosis for the entire cohort was $660 ($402) per patient over the 1-year period after diagnosis. Patients who continued to be treated conservatively between 6 and 12 months after diagnosis incurred relatively low median costs of $168 per patient. CONCLUSION: In this cohort, a second encounter with a physician for tennis elbow was a strong predictor of increased treatment cost due to a higher likelihood of specialist referral, use of physical therapy, or treatment with steroid injection. CLINICAL RELEVANCE: The majority of direct medical spending on tennis elbow occurs within the first 6 months of treatment, and relatively little expense occurs between 6 and 12 months after diagnosis unless a patient undergoes surgical intervention.

Direct Medical Costs Attributable to Cancer-Associated Venous Thromboembolism: A Population-Based Longitudinal Study.

PURPOSE: The purpose of this study is to estimate medical costs attributable to venous thromboembolism among patients with active cancer. METHODS: In a population-based cohort study, we used Rochester Epidemiology Project (REP) resources to identify all Olmsted County, Minn. residents with incident venous thromboembolism and active cancer over the 18-year period, 1988-2005 (n = 374). One Olmsted County resident with active cancer without venous thromboembolism was matched to each case on age, sex, cancer diagnosis date, and duration of prior medical history. Subjects were followed forward in REP provider-linked billing data for standardized, inflation-adjusted direct medical costs from 1 year prior to index (venous thromboembolism event date or control-matched date) to the earliest of death, emigration from Olmsted County, or December 31, 2011, with censoring on the shortest follow-up to ensure a similar follow-up duration for each case-control pair. We used generalized linear modeling to predict costs for cases and controls and bootstrapping methods to assess uncertainty and significance of mean adjusted cost differences. Outpatient drug costs were not included in our estimates. RESULTS: Adjusted mean predicted costs were 1.9-fold higher for cases ($49,351) than for controls ($26,529) (P < .001) from index to up to 5 years post index. Cost differences between cases and controls were greatest within the first 3 months (mean difference = $13,504) and remained significantly higher from 3 months to 5 years post index (mean difference = $12,939). CONCLUSIONS: Venous thromboembolism-attributable costs among patients with active cancer contribute a substantial economic burden and are highest from index to 3 months, but may persist for up to 5 years.

Costs of venous thromboembolism associated with hospitalization for medical illness.

OBJECTIVES: To determine population-based estimates of medical costs attributable to venous thromboembolism (VTE) among patients currently or recently hospitalized for acute medical illness. STUDY DESIGN: Population-based cohort study conducted in Olmsted County, Minnesota. METHODS: Using Rochester Epidemiology Project (REP) resources, we identified all Olmsted County residents with objectively diagnosed incident VTE during or within 92 days of hospitalization for acute medical illness over the 18-year period of 1988 to 2005 (n=286). One Olmsted County resident hospitalized for medical illness without VTE was matched to each case for event date (±1 year), duration of prior medical history, and active cancer status. Subjects were followed forward in REP provider-linked billing data for standardized, inflation-adjusted direct medical costs (excluding outpatient pharmaceutical costs) from 1 year before their respective event or index date to the earliest of death, emigration from Olmsted County, or December 31, 2011 (study end date). We censored follow-up such that each case and matched control had similar periods of observation. We used generalized linear modeling (controlling for age, sex, preexisting conditions, and costs 1 year before index) to predict costs for cases and controls. RESULTS: Adjusted mean predicted costs were 2.5-fold higher for cases ($62,838) than for controls ($24,464) (P<.001) from index to up to 5 years post index. Cost differences between cases and controls were greatest within the first 3 months after the event date (mean difference=$16,897) but costs remained significantly higher for cases compared with controls for up to 3 years. CONCLUSIONS: VTE during or after recent hospitalization for medical illness contributes a substantial economic burden.

Trends in the epidemiology of osteomyelitis: a population-based study, 1969 to 2009.

BACKGROUND: The epidemiology of osteomyelitis in the United States is largely unknown. The purpose of this study was to determine long-term secular trends in the incidence of osteomyelitis in a population-based setting. METHODS: The study population comprised 760 incident cases of osteomyelitis first diagnosed between January 1, 1969, and December 31, 2009, among residents of Olmsted County, Minnesota. The complete medical records for each potential subject were reviewed to confirm the osteomyelitis diagnosis and to extract details on anatomical sites, infecting organisms, etiological risk factors, and outcomes. RESULTS: The overall age and sex-adjusted annual incidence of osteomyelitis was 21.8 cases per 100,000 person-years. The annual incidence was higher for men than for women and increased with age (p < 0.001). Rates increased with the calendar year (p < 0.001) from 11.4 cases per 100,000 person-years in the period from 1969 to 1979 to 24.4 per 100,000 person-years in the period from 2000 to 2009. The incidence remained relatively stable among children and young adults but almost tripled among individuals older than sixty years; this was partly driven by a significant increase in diabetes-related osteomyelitis from 2.3 cases per 100,000 person-years in the period from 1969 to 1979 to 7.6 cases per 100,000 person-years in the period from 2000 to 2009 (p < 0.001). Forty-four percent of cases involved Staphylococcus aureus infections. CONCLUSIONS: The reasons for the increase in osteomyelitis between 1969 and 2009 are unclear but could comprise a variety of factors, including changes in diagnosing patterns or increases in the prevalence of risk factors (e.g., diabetes) in this population.

Direct medical costs and source of cost differences across the spectrum of cognitive decline: a population-based study.

BACKGROUND: Objective cost estimates and source of cost differences are needed across the spectrum of cognition, including cognitively normal (CN), mild cognitive impairment (MCI), newly discovered dementia, and prevalent dementia. METHODS: Subjects were a subset of the Mayo Clinic Study of Aging stratified-random sampling of Olmsted County, MN, residents aged 70 to 89 years. A neurologist reviewed provider-linked medical records to identify prevalent dementia (review date = index). Remaining subjects were invited to participate in prospective clinical/neuropsychological assessments; participants were categorized as CN, MCI, or newly discovered dementia (assessment date = index). Costs for medical services/procedures 1-year pre-index (excluding indirect and long-term care costs) were estimated using line-item provider-linked administrative data. We estimated contributions of care-delivery site and comorbid conditions (including and excluding neuropsychiatric diagnoses) to between-category cost differences. RESULTS: Annual mean medical costs for CN, MCI, newly discovered dementia, and prevalent dementia were $6042, $6784, $9431, $11,678, respectively. Hospital inpatient costs contributed 70% of total costs for prevalent dementia and accounted for differences between CN and both prevalent and newly discovered dementia. Ambulatory costs accounted for differences between CN and MCI. Age-, sex-, education-adjusted differences reached significance for CN versus newly discovered and prevalent dementia and for MCI versus prevalent dementia. After considering all comorbid diagnoses, between-category differences were reduced (e.g., prevalent dementia minus MCI (from $4842 to $3575); newly discovered dementia minus CN (from $3578 to $711)). Following the exclusion of neuropsychiatric diagnoses from comorbidity adjustment, between-category differences tended to revert to greater differences. CONCLUSIONS: Cost estimates did not differ significantly between CN and MCI. Substantial differences between MCI and prevalent dementia reflected high inpatient costs for dementia and appear partly related to co-occurring mental disorders. Such comparisons can help inform models aimed at identifying where, when, and for which individuals proposed interventions might be cost-effective.

The epidemiology and health care burden of tennis elbow: a population-based study.

BACKGROUND: Lateral elbow tendinosis (epicondylitis) is a common condition both in primary care and specialty clinics. PURPOSE: To evaluate the natural history (ie, incidence, recurrence, and progression to surgery) of lateral elbow tendinosis in a large population. STUDY DESIGN: Descriptive epidemiology study. METHODS: The study population comprised a population-based incidence cohort of patients with new-onset lateral elbow tendinosis between January 1, 2000, and December 31, 2012. The medical records of a 10% random sample (n=576) were reviewed to ascertain information on patient and disease characteristics, treatment modalities, recurrence, and progression to surgery. Age- and sex-specific incidence rates were calculated and adjusted to the 2010 US population. RESULTS: The age- and sex-adjusted annual incidence of lateral elbow tendinosis decreased significantly over time from 4.5 per 1000 people in 2000 to 2.4 per 1000 in 2012 (P<.001). The recurrence rate within 2 years was 8.5% and remained constant over time. The proportion of surgically treated cases within 2 years of diagnosis tripled over time, from 1.1% during the 2000-2002 time period to 3.2% after 2009 (P<.00001). About 1 in 10 patients with persistent symptoms at 6 months required surgery. CONCLUSION: The decrease in incidence of lateral elbow tendinosis may represent changes in diagnosis patterns or a true decrease in disease incidence. Natural history data can be used to help guide patients and providers in determining the most appropriate course at a given time in the disease process. The study data suggest that patients without resolution after 6 months of onset may have a prolonged disease course and may need surgical intervention.

Direct medical costs attributable to venous thromboembolism among persons hospitalized for major operation: a population-based longitudinal study.

BACKGROUND: We estimated medical costs attributable to venous thromboembolism (VTE) among patients currently or recently hospitalized for major operation. METHODS: Using Rochester Epidemiology Project resources, we identified all Olmsted County, MN, residents with objectively diagnosed incident VTE within 92 days of hospitalization for major operation during an 18-year period, 1988-2005 (n = 355). One Olmsted County resident hospitalized for major operation without VTE was matched to each case on event date (±1 year), type of operation, duration of previous medical history, and active cancer status. Subjects were followed in Rochester Epidemiology Project provider-linked billing data for standardized, inflation-adjusted direct medical costs from 1 year before index (case's VTE event date and control's matched date) to earliest of death, emigration, or December 31, 2011. We used generalized linear modeling to predict costs for cases and controls and used bootstrapping methods to assess uncertainty and significance of mean adjusted cost differences. RESULTS: Adjusted mean predicted costs were more than 1.5-fold greater for cases ($55,956) than for controls ($32,718) (P ≤ .001) from index to up to 5 years postindex. Cost differences between cases and controls were greatest within the first 3 months after index (mean difference = $12,381). Costs were greater for cases than controls (mean difference = $10,797) from 3 months to up to 5 years postindex and together accounted for about half of the overall cost difference. CONCLUSION: VTE during or after recent hospitalization for major operation contributes a substantial economic burden; VTE-attributable costs are greatest in the initial 3 months but persist for up to 5 years.