Assessing the reliability of CBCT-based AI-generated STL files in diagnosing osseous changes of the mandibular condyle: a comparative study with ground truth diagnosis.

OBJECTIVES: This study aims to evaluate the reliability of AI-generated STL files in diagnosing osseous changes of the mandibular condyle and compare them to a ground truth (GT) diagnosis made by six radiologists. METHODS: A total of 432 retrospective CBCT images from four universities were evaluated by six dentomaxillofacial radiologists who identified osseous changes such as flattening, erosion, osteophyte formation, bifid condyle formation, and osteosclerosis. All images were evaluated by each radiologist blindly and recorded on a spreadsheet. All evaluations were compared and for the disagreements, a consensus meeting was held online to create a uniform GT diagnosis spreadsheet. A web-based dental AI software was used to generate STL files of the CBCT images, which were then evaluated by two dentomaxillofacial radiologists. The new observer, GT, was compared to this new STL file evaluation, and the interclass correlation (ICC) value was calculated for each pathology. RESULTS: Out of the 864 condyles assessed, the ground truth diagnosis identified 372 cases of flattening, 185 cases of erosion, 70 cases of osteophyte formation, 117 cases of osteosclerosis, and 15 cases of bifid condyle formation. The ICC values for flattening, erosion, osteophyte formation, osteosclerosis, and bifid condyle formation were 1.000, 0.782, 1.000, 0.000, and 1.000, respectively, when comparing diagnoses made using STL files with the ground truth. CONCLUSIONS: AI-generated STL files are reliable in diagnosing bifid condyle formation, osteophyte formation, and flattening of the condyle. However, the diagnosis of osteosclerosis using AI-generated STL files is not reliable, and the accuracy of diagnosis is affected by the erosion grade.

Degenerative changes of the mandibular condyle in relation to the temporomandibular joint space, gender and age: A multicenter CBCT study.

BACKGROUND: Cone-beam computed tomography (CBCT) is used to provide multiplanar views of the temporomandibular joint (TMJ) bone components as well as TMJ pathologies without superposition, magnification or distortion. OBJECTIVES: The study aimed to analyze degenerative changes in the condylar surface, and their relationship with patient age and gender, and the TMJ space measurements by using CBCT images. MATERIAL AND METHODS: A total of 258 individuals were retrospectively analyzed. The degenerative bone changes of the condylar head were evaluated and classified on the right and left sides. The shortest distances from the anterior, superior and posterior parts of the condylar head to the glenoid fossa were measured to represent the TMJ space. Univariate and multivariate logistic regression analyses then evaluated the effect of age and gender on the presence of degenerative changes. RESULTS: Condylar flattening was most frequently observed (413 TMJs, 53.5%). However, the presence or absence of the change types did not differ according to the sides. The mean values of the TMJ space measurements on the right and left sides were narrower in the group with changes than in the group without changes. Nonetheless, no statistically significant difference in the TMJ space was found between the groups (p > 0.05). CONCLUSIONS: An increased risk of radiographically detectable degenerative alterations in left TMJs was detected for males and for increasing age. Degenerative changes in the condylar surface may affect the dimensions of the TMJ space.

Comparison of CBCT with different voxel sizes and intraoral scanner for detection of periodontal defects: an in vitro study.

OBJECTIVES: This study aimed to compare the diagnostic accuracy of cone beam CT (CBCT) units with different voxel sizes with the digital intraoral scanning technique in terms of the detection of periodontal defects. METHODS AND MATERIALS: The study material comprised of 12 dry skulls with maxilla and mandible. Artificial defects were created on teeth separately using burs randomly on dry skulls. In total 46 dehiscences, 10 fenestrations, 17 furcations, 12 wall defects and 13 without periodontal defect were used in the study. Each tooth with and without defects was imaged at various vertical angles using each of the following modalities: a Veraviewepocs 3D R100 CBCT device and a 3D Shape TRIOSㄾ Color P13 Shade Intraoral Scanner. RESULTS: The κ values for interobserver agreement between observers ranged between 0.29 and 0.86 for the CBCT 10 × 8 cm field of view (FOV) with 0,160 mm3 voxel size; 0.35 and 1 for the CBCT 8 × 8 cm FOV with 0,125 mm3 voxel size; and 0.30 and 1 of intraoral scans. The κ values for detecting defects on anterior teeth were the least, following premolar and molar teeth both CBCT and intraoral scanning. CONCLUSIONS: Smaller voxel sizes and smaller CBCT FOV has the highest sensitivity and diagnostic accuracy for detecting various periodontal defects among the scanner modalities examined. ADVANCES IN KNOWLEDGE: Adequate evaluation of the condition of the alveolar bone and periodontal tissues is important for the diagnosis, treatment, and prognosis of periodontal disease. Limited examination methods, such as palpation, inspection, and periodontal probe examination, may provide insufficient information for the diagnosis of periodontal diseases.

Cone-beam computed tomography evaluation of the pterygomaxillary fissure and pterygopalatine fossa using 3D rendering programs.

PURPOSE: The aim of this study was to investigate the detailed anatomy of the pterygomaxillary fissure (PMF) and pterygopalatine fossa (PPF) and variations therein using three-dimensional (3D) cone-beam computed tomography (CBCT) software. METHODS: This study was based on a retrospective evaluation of CBCT scans. A total of 825 CBCT images of patients (448 females, 377 males) who met the inclusion criteria were analyzed. PMF shapes were classified, and morphometric measurements (PMF area and PPF volume) were performed according to age, right/left side, and gender using 3D rendering programs. Maxillary and sphenoid sinus pathologies were also classified to reveal possible correlations between morphometric measurements. Analysis of variance was used for comparisons. Multiple comparisons were assessed using the Bonferroni test. Pearson's test was used to assess correlations between parameters. A p value < 0.05 was considered to indicate statistical significance. RESULTS: Six types of PMF shapes were defined. There were no significant differences in types according to gender, age or sinus pathology. Males had a significantly larger PMF area than females (p < 0.001). Left/right comparison of the PMF area revealed that the mean PMF coronal, axial, and sagittal area dimensions were significantly higher on the right side in all patients. Our results also indicated that the PMF area and PPF volume increased significantly after 40 years of age. CONCLUSION: Various PMF shapes were defined and classified. PMF and PPF dimensions increased with age. Knowledge of these anatomical variations will allow surgeons to avoid damage to the neurovascular structures passing through the area.

Prevalence of periodontal disease among mine workers of Zonguldak, Kozlu District, Turkey: a cross-sectional study.

BACKGROUND: Occupational injuries cause major health problems in all nations. Coal mining is one of the largest, oldest industries in the world. However, there is relatively little available literature concerning the health status of coal miners. The purpose of this work is to assess the prevalence of periodontal disease among coal miners and provide a basis for planning and evaluating the data from community oral health services. METHODS: A cross-sectional study was conducted 106 men selected based on a stratified cluster sampling procedure. The study was performed among the mine workers of Zonguldak, Kozlu District, Turkey. The questionnaire prepared by the American Academy of Periodontology risk assessment test was used for the evaluation. The data were collected byWorld Health Organization (WHO) oral health assessment form, and clinical examination was conducted by the method recommended by the WHO oral health surveys. Statistical analysis was performed using SPSS software programme. RESULTS: The overall prevalence of periodontal disease was found to be 96.2% and was determined by considering subjects with Community Periodontal Index scores of 1-4 as diseased and the healthy subjects comprised of a mere 3.8%. Furthermore, various disturbing or embarrassing work conditions were reported. Statistically significant differences were observed among the workers who brush their teeth daily and visit dental attendance within the last two years have better periodontal status than those of the others (p < 0.05). CONCLUSIONS: The present level of periodontal disease in coal mine workers is severe. Moreover, its distribution and severity are strongly influenced by host susceptibility and risk factors. The priority should be based on population strategy and primary prevention programmes to benefit the periodontal health by promoting self-care and oral hygiene.

Evaluation of the accuracy of cone beam computed tomography on measuring impacted supernumerary teeth.

Supernumerary teeth may affect the tooth eruption negatively if they occur on the eruption way, and the treatment choice is usually the extraction to prevent the impaction of adjacent permanent teeth. CBCT enables clear and three dimensional images, and it may be helpful to determine the exact location and to measure the dimensions of the supernumerary tooth to avoid any complication during the extraction process. The aim of the present study was to evaluate the accuracy of CBCT on measuring the tooth length and crown width of impacted supernumerary teeth. Twenty-five impacted supernumerary teeth were evaluated using CBCT, and each sample's tooth length and crown width were measured prior to the extraction. After all the extractions were completed, the actual measurements were performed on the same samples. The differences between CBCT and actual measurements were evaluated statistically. Measurements on CBCT images were significantly larger than the actual measurements on tooth length and crown width. For tooth length and crown width, p value was found as 0.045, and <0.001, respectively. The results of the present study should be considered as important by clinicians during the treatment planning to decrease any complication risk under certain conditions such as being so close to an important anatomical structure or the root of an adjacent tooth. SCANNING 38:579-584, 2016. © 2016 Wiley Periodicals, Inc.

Risk and predictors of cardiovascular disease in psoriasis: a population-based study.

BACKGROUND: Emerging evidence suggests that severe psoriasis is associated with increased risk of cardiovascular disease. The goal of this study was to examine the risk and predictors of clinical cardiovascular events in psoriasis. METHODS: We performed a historical cohort and a nested case-cohort study using the population-based resources in Olmsted County, Minnesota. The study population included a population-based incidence cohort of patients with psoriasis first diagnosed between January 1, 1970, and January 1, 2000, and 2678 age- and sex-matched non-psoriasis subjects. Cardiovascular events, including hospitalized myocardial infarction, coronary revascularization procedures, stroke, heart failure, and cardiovascular death. RESULTS: Psoriasis was associated with an increased risk of myocardial infarction based on diagnostic codes (hazard ratio 1.26; 95% confidence intervals: 1.01, 1.58) but not when the analyses were restricted to validated myocardial infarction (hazard ratio 1.18; 95% confidence intervals: 0.80, 1.74). Psoriasis was not associated with an increased risk of heart failure or cardiovascular death. Traditional cardiovascular risk factors were significantly associated with cardiovascular risk in psoriasis. Each 1% increase in Framingham risk score at psoriasis incidence corresponded with a 5-10% increase in risk of cardiovascular events. CONCLUSION: In this large incidence cohort of patients with psoriasis representing the full disease severity spectrum, psoriasis was not associated with an increased cardiovascular risk.

The effect of removable partial dentures on alveolar bone resorption: a retrospective study with cone-beam computed tomography.

PURPOSE: The aim of this study was to compare vertical and horizontal mandibular alveolar bone resorption by measuring bone morphological variation in Kennedy Class II removable partial denture (RPD) wearers and non-wearers using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: In total, 124 sites in the CBCT scans of 62 (29 RPD non-wearers, 33 RPD wearers) Kennedy Class II patients were analyzed retrospectively. Three-dimensional representations of the mandible with superimposed cross-sectional slices were developed with the CBCT scans to evaluate the mandibular alveolar height and width by measuring distances between the mandibular canal, mylohyoid ridge, alveolar crest, and lower border of the mandible in four regions (eight sites) of Kennedy Class II non-wearers and wearers of RPDs. RESULTS: Mandibular alveolar bone height and width were significantly lower in edentulous sites when compared with dentate sites in both Kennedy Class II non-wearers and wearers of RPDs (p < 0.05). Additionally, mean vertical and horizontal mandibular bone resorption was significantly higher in RPD wearers than in non-wearers (p < 0.05). CONCLUSIONS: Vertical and horizontal alveolar bone resorption was found to be higher in the RPD wearing patients when comparing the dentate and edentulous sites.

Large arteriovenous malformation of the oromaxillofacial region with multiple phleboliths.

Vascular tumors are the most common benign tumors of the head and neck in infancy and childhood. Vascular anomalies of the head and neck were divided into 2 categories including hemangiomas and vascular malformations. Oral and maxillofacial hemangiomas and vascular malformations are congenital lesions with various clinical characteristics, manifestations, indications, and possibilities for treatment. This paper reports a case of large arteriovenous malformations including a description of the features demonstrated by panoramic radiography, cone beam computed tomography, and magnetic resonance imaging. The differential diagnosis and treatment modalities (including embolization with N-butylcyanoacrylate in this case) are also discussed following the case presentation, along with the available literature review.

Global transcriptional analysis of psoriatic skin and blood confirms known disease-associated pathways and highlights novel genomic "hot spots" for differentially expressed genes.

There are major gaps in our knowledge regarding the exact mechanisms and genetic basis of psoriasis. To investigate the pathogenesis of psoriasis, gene expression in 10 skin (5 lesional, 5 nonlesional) and 11 blood (6 psoriatic, 5 nonpsoriatic) samples were examined using Affymetrix HG-U95A microarrays. We detected 535 (425 upregulated, 110 downregulated) DEGs in lesional skin at 1% false discovery rate (FDR). Combining nine microarray studies comparing lesional and nonlesional psoriatic skin, 34.5% of dysregulated genes were overlapped in multiple studies. We further identified 20 skin and 2 blood associated transcriptional "hot spots" at specified genomic locations. At 5% FDR, 11.8% skin and 10.4% blood DEGs in our study mapped to one of the 12 PSORS loci. DEGs that overlap with PSORS loci may offer prioritized targets for downstream genetic fine mapping studies. Novel DEG "hot spots" may provide new targets for defining susceptibility loci in future studies.

Epidemiology and clinical characteristics of Behçet's disease in the US: a population-based study.

OBJECTIVE: Behçet's disease (BD) is a rare, multisystem inflammatory disorder of unknown cause. Although well-documented in Eastern populations, epidemiologic data is scarce in North American countries. Here we describe the incidence and prevalence of BD in Olmsted County, Minnesota over 45 years. METHODS: We identified an incidence cohort of subjects age >/=18 years who had a clinical diagnosis of and/or fulfilled the International Study Group (ISG) criteria for BD from January 1, 1960 to January 1, 2005. Age- and sex-specific incidence and prevalence were estimated and age- and sex-adjusted to the 2000 US total population. RESULTS: The study population was comprised of 13 subjects with BD; 11 fulfilled ISG criteria between 1960 and 2005. Mean +/- SD age was 31 +/- 9 years, and 69% were white. Point prevalence in 2000 was 5.2 per 100,000 population (95% confidence interval [95% CI] 0.64-9.84). The overall annual age- and sex-adjusted incidence of BD was 0.38 per 100,000 population (95% CI 0.17-0.59), with a higher incidence in women (0.51 per 100,000; 95% CI 0.17-0.84) than in men (0.26 per 100,000; 95% CI 0.004-0.52). Dermatologic lesions included oral ulcers (100%), genital ulcers (62%), erythema nodosum (46%), and papulopustular lesions (54%). Ocular lesions, vascular complications, and central nervous system involvement were present in 8, 3, and 3 subjects, respectively. CONCLUSION: Our study shows an overall incidence of 0.38 per 100,000 population, which is comparable with other Western populations. The prevalence of 5.2 per 100,000 population is similar to estimates reported in Western countries, but lower than that in countries along the Silk Road.

The presentation of headache in neuro-Behçet's disease: a case-series.

INTRODUCTION: Behçet's disease (BD) is a chronic, relapsing, multisystemic, inflammatory disorder with unknown etiology. Neurological involvement is observed in about 5% of the patients with BD and headache is a frequently reported symptom with or without neurological involvement. In this case-series, we aim to demonstrate the secondary headaches associated with neuro-Behçet's disease in consecutive BD patients who had been referred for neurologic evaluation. METHODS: The case-series included 17 patients (11 males [65%]), mean age 41 +/- 11.4, who met the criteria for BD established by the International Study Group for BD and developed headache during the disease course. RESULTS: Seventeen BD patients were identified, the neurologic presentations included in parenchymal involvement 12 (70%), extraparenchymal involvement/venous thrombosis in 5 (30%), seizure disorder in 2 (12%), and psychiatric problems/depression or anxiety in 5 (30%) patients, respectively. The characteristics of the headache according to the patients' reports included subacute, moderate to severe headache with unilateral localization and throbbing quality accompanied by nausea, vomiting, and aggravation upon awakening. CONCLUSION: Because neurological involvement is one of the most devastating aspects of BD, the need to treat neurological involvement as early as possible, the possible role of headache onset as an early indicator for neurological involvement in this relatively uncommon disease should be kept in mind.

Time trends in epidemiology and characteristics of psoriatic arthritis over 3 decades: a population-based study.

OBJECTIVE: To determine time trends in incidence, prevalence, and clinical characteristics of psoriatic arthritis (PsA) over a 30-year period. METHODS: We identified a population-based incidence cohort of subjects aged 18 years or over who fulfilled ClASsification of Psoriatic ARthritis (CASPAR) criteria for PsA between January 1, 1970, and December 31, 1999, in Olmsted County, Minnesota, USA. PsA incidence date was defined as the diagnosis date of those who fulfilled CASPAR criteria. Age- and sex-specific incidence rates were estimated and age- and sex-adjusted to the 2000 US White population. RESULTS: The PsA incidence cohort comprised 147 adult subjects with a mean age of 42.7 years, and 61% were men. The overall age- and sex-adjusted annual incidence of PsA per 100,000 was 7.2 [95% confidence interval (CI) 6.0, 8.4] with a higher incidence in men (9.1, 95% CI 7.1, 11.0) than women (5.4, 95% CI 4.0, 6.9). The age- and sex-adjusted incidence of PsA per 100,000 increased from 3.6 (95% CI 2.0, 5.2) between 1970 and 1979 to 9.8 (95% CI 7.7, 11.9) between 1990 and 2000 (p for trend < 0.001). The point prevalence per 100,000 was 158 (95% CI 132, 185) in 2000, with a higher prevalence in men (193, 95% CI 150, 237) than women (127, 95% CI 94, 160). At incidence, most PsA subjects had oligoarticular involvement (49%) with enthesopathy (29%). CONCLUSION: The incidence of PsA has been rising over 30 years in men and women. Reasons for the increase are unknown, but may be related to a true change in incidence or greater physician awareness of the diagnosis.

Trends in incidence of adult-onset psoriasis over three decades: a population-based study.

BACKGROUND: Incidence studies of psoriasis are rare, mainly due to lack of established epidemiological criteria and the variable disease course. The objective of this study is to determine time trends in incidence and survival of psoriasis patients over three decades. METHODS: We identified a population-based incidence cohort of 1633 subjects aged > or = 18 years first diagnosed with psoriasis between January 1, 1970 and January 1, 2000. The complete medical records for each potential psoriasis subject were reviewed and diagnosis was validated by either 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 the 2000 US white population. RESULTS: The overall age- and sex-adjusted annual incidence of psoriasis was 78.9 per 100,000 (95% confidence interval [CI]: 75.0-82.9). When psoriasis diagnosis was restricted to dermatologist-confirmed subjects, the incidence was 62.3 per 100,000 (95% CI: 58.8-65.8). Incidence of psoriasis increased significantly over time from 50.8 in the period 1970-1974 to reach 100.5 per 100,000 in the 1995-1999 time period (P = .001). Although the overall incidence was higher in males than in females (P = .003), incidence in females was highest in the sixth decade of life (90.7 per 100,000). Survival was similar to that found in the general population (P = .36). LIMITATIONS: The study population was mostly white and limited to adult psoriasis patients. CONCLUSION: The annual incidence of psoriasis almost doubled between the 1970s and 2000. The reasons for this increase in incidence are currently unknown, but could include a variety of factors, including a true change in incidence or changes in the diagnosing patterns over time.

Incidence and clinical predictors of psoriatic arthritis in patients with psoriasis: a population-based study.

OBJECTIVE: To determine the incidence and disease-specific predictors of clinically recognized psoriatic arthritis (PsA) in patients with psoriasis. METHODS: We identified an incidence cohort of psoriasis subjects age >/=18 years diagnosed between January 1, 1970 and December 31, 1999 in a population-based setting. Psoriasis diagnoses were validated by confirmatory diagnosis in the medical record. Incident and clinically recognized PsA subjects were classified according to the Classification of Psoriatic Arthritis (CASPAR) criteria. Cox proportional hazards models were used to identify predictors of PsA within the psoriasis cohort. RESULTS: The psoriasis incidence cohort comprised 1,633 subjects. Of these, 40 were diagnosed with PsA concurrently with psoriasis and were excluded from analysis. The remaining 1,593 psoriasis subjects had a mean age of 43 years and 50% were men. Over 20,936 person-years of followup, 57 subjects were clinically recognized with new-onset PsA, with a cumulative incidence of 1.7% (95% confidence interval [95% CI] 1.0-2.3%), 3.1% (95% CI 2.2-4.1%), and 5.1% (95% CI 3.7-6.6%) at 5, 10, and 20 years following psoriasis incidence, respectively. Psoriasis features associated with higher risk of PsA were scalp lesions (hazard ratio [HR] 3.89, 95% CI 2.18-6.94), nail dystrophy (HR 2.93, 95% CI 1.68-5.12), and intergluteal/perianal lesions (HR 2.35, 95% CI 1.32-4.19). Calendar year was not associated with risk of PsA (P = 0.15), indicating that the likelihood of PsA in psoriasis subjects did not change over time. CONCLUSION: In this population-based study, <10% of patients with psoriasis developed clinically recognized PsA during a 30-year period. Psoriasis features associated with a higher likelihood of PsA were nail dystrophy, scalp lesions, and intergluteal/perianal psoriasis.

Systemic lupus erythematosus features in rheumatoid arthritis and their effect on overall mortality.

OBJECTIVE: Features of systemic lupus erythematosus (SLE) are commonly observed in patients with rheumatoid arthritis (RA). However, their frequency and clinical significance are uncertain. We examined the frequency of SLE features in RA and their effect on overall mortality. METHODS: We assembled a population-based incidence cohort of subjects aged >or=18 years first diagnosed with RA [1987 American College of Rheumatology (ACR) criteria] between 1955 and 1995. Information regarding disease characteristics, therapy, comorbidities, and SLE features (1982 ACR criteria) were collected from the complete inpatient and outpatient medical records. Cox regression models were used to estimate the mortality risk associated with lupus features. RESULTS: The study population comprised 603 subjects with incident RA (mean age 58 yrs, 73% women) with a mean followup time of 15 years. By 25 years after RA incidence, >or=4 SLE features were observed in 15.5% of the subjects with RA. After adjustment for age and sex, occurrence of >or=4 SLE features was associated with increased overall mortality [hazard ratio (HR) 5.54, 95% confidence interval (CI) 3.59-8.53].With further adjustment for RA characteristics, therapy, and comorbidities, the association weakened but remained statistically significant (HR 2.56, 95% CI 1.60-4.08). After adjustment for age, sex, RA characteristics, therapy, and comorbidities, thrombocytopenia (2.0, 95% CI 1.2, 3.1) and proteinuria (1.8, 95% CI 1.3, 2.6) were significantly associated with mortality. CONCLUSION: SLE features were common in RA, given sufficient observation time. Subjects with RA who developed >or=4 SLE features had an increased risk of death. Proteinuria and thrombocytopenia were individually associated with an increased mortality risk.

Clustering of organ-specific autoimmunity: a case presentation of multiple sclerosis and connective tissue disorders.

Multiple sclerosis (MS) is the most common demyelinating disease caused by an autoimmune inflammatory process in the central nervous system (CNS) and is associated with aberrant immune response to myelin selfantigens. Coexistence of MS with other autoimmune disorders, including connective tissue disorders including systemic lupus erythematosus, rheumatoid arthritis, Sjögren's syndrome and scleroderma have been reported previously. In the present article we report the coexistence of MS, familial mediterranean fever and ankylosing spondylitis in a patient and review the clinical presentation, neurologic findings, cerebrospinal fluid and radiologic characteristics and treatment options. We further discuss the immunopathogenetic mechanisms for a possible association between MS and autoimmune disorders.

Potential misclassification of patients with psoriasis in electronic databases.

BACKGROUND: Electronic claims and medical record databases are increasingly used for observational studies of psoriasis. The purpose of this study was to assess the validity of psoriasis diagnostic codes in an electronic database. METHODS: This study was performed in a population-based setting in Olmsted County, Minnesota, where all diagnoses and procedures from all health care providers in a large community are indexed and recorded in an electronic database. The database was searched for patients aged 18 years or older with diagnostic codes consistent with psoriasis for the time period January 1, 1976, to January 1, 2000. The complete medical records of all patients were reviewed manually for validation of psoriasis diagnoses. RESULTS: We reviewed the complete medical records of 2556 patients with at least one diagnostic code consistent with psoriasis. Based on medical record review, 1458 (57.0%) patients were confirmed to have psoriasis, of which the majority (81%) received confirmation by a dermatologist. The most commonly used diagnostic codes for psoriasis were International Classification of Diseases, Ninth Revision 696.1 (psoriasis, not otherwise specified) with a positive predictive value of 68.7% (95% confidence interval: 66.5%, 70.9%). Increasing frequency of codes in a given time window was associated with positive predictive values. However, positive predictive value for only one code in a 5-year time window was still as high as 60% (95% confidence interval: 57%, 63%). LIMITATIONS: Differences between individual electronic medical record databases may limit the ability to form a general conclusion from these findings. The remitting, relapsing course of psoriasis and the heterogeneity in clinical presentation create challenges in case ascertainment. CONCLUSION: Electronic identification of patients with psoriasis by diagnostic codes alone may lead to misclassification in database studies.

Mortality trends in rheumatoid arthritis: the role of rheumatoid factor.

OBJECTIVE: We previously demonstrated a widening in the mortality gap between subjects with rheumatoid arthritis (RA) and the general population. We examined the contribution of rheumatoid factor (RF) positivity on overall mortality trends and cause-specific mortality. METHODS: A population-based RA incidence cohort (1955-1995, and aged >or= 18 yrs) was followed longitudinally until death or January 1, 2006. The underlying cause of death as coded from national mortality statistics and grouped according to ICD-9/10 chapters was used to define cause-specific mortality. Expected cause-specific mortality rates were estimated by applying the age-, sex-, and calendar-year-specific mortality rates from the general population to the RA cohort. Poisson regression was used to model the observed overall and cause-specific mortality rates according to RF status, accounting for age, sex, disease duration, and calendar year. RESULTS: A cohort of 603 subjects (73% female; mean age 58 yrs) with RA was followed for a mean of 16 years, during which 398 died. Estimated survival at 30 years after RA incidence was 26.0% in RF+ RA subjects compared to 36.0% expected (p < 0.001), while in RF- RA subjects, estimated survival was 29.1% compared to 28.3% expected (p = 0.9). The difference between the observed and the expected mortality in the RF+ RA subjects increased over time, resulting in a widening of the mortality gap, while among RF- RA subjects, observed mortality was very similar to the expected mortality over the entire time period. Among RF+ RA subjects, cause-specific mortality was higher than expected for cardiovascular [relative risk (RR) 1.50; 95% confidence interval (CI) 1.22, 1.83] and respiratory diseases [RR 3.49; 95% CI 2.51, 4.72]. Among RF- RA subjects, no significant differences were found between observed and expected cause-specific mortality. CONCLUSION: The widening in the mortality gap between RA subjects and the general population is confined to RF+ RA subjects and largely driven by cardiovascular and respiratory deaths.