Risk of Incident Colorectal Cancer and Death After Colonoscopy: A Population-based Study in Utah.

BACKGROUND & AIMS: Colonoscopy is widely recommended for colorectal (CRC) screening in the United States, but evidence of effectiveness is limited. We examined whether exposure to colonoscopy decreases the odds of incident CRC and death from CRC in Utah. METHODS: We performed a case-control study of Utah residents, 54 to 90 years old, who received a CRC diagnosis from 2000 through 2010 (cases). Age- and sex-matched controls with no history of CRC (controls) were selected for each case. We determined receipt of colonoscopy 6 months to 10 years before the reference date for each case and control through administrative claims data. Colonoscopy exposure was compared by using conditional logistic regression. RESULTS: We identified 5128 cases and 20,512 controls; 741 cases (14%) and 5715 controls (28%) received a colonoscopy. Exposure to colonoscopy reduced the odds for a diagnosis of CRC; the odds ratios (ORs) were 0.41 for any CRC (95% confidence interval [CI], 0.38-0.44), 0.58 for proximal colon cancer (95% CI, 0.51-0.65), and 0.29 for distal colon or rectal cancer (95% CI, 0.25-0.33). This finding was consistent among sexes, age groups, and cancer stages. Similarly, in a subgroup analysis, colonoscopy was associated with decreased odds of death from CRC (OR, 0.33; 95% CI, 0.28-0.39) in both the proximal colon (OR, 0.43; 95% CI, 0.34-0.55) and distal colon or rectum (OR, 0.23; 95% CI, 0.18-0.30). CONCLUSIONS: In the population of Utah, colonoscopy is associated with a large reduction in risk of new-onset CRC and death from CRC. This reduction in risk for CRC was greatest for the distal colon and rectum, with a more modest reduction for proximal colon cancer.

Parental influence on systemic sclerosis.

OBJECTIVE: To examine parental influence on the development of systemic sclerosis (SSc; scleroderma). We designed 3 studies: mitochondrial inheritance, birth order (a possible surrogate marker for microchimerism), and paternal age at conception (a possible surrogate for telomere erosion) to examine their association with development of SSc. METHODS: SSc was defined by International Classification of Diseases, Ninth and Tenth Revision codes (ICD-9 710.1 and ICD 10 M34.0, M34.1, and M34.9) and identified from statewide discharge data, University of Utah Health Science Center Enterprise Data Warehouse (UUHSC), and death certificates that were linked to the Utah Population Database (UPDB) for analysis. Mitochondrial inheritance was evaluated by conditional logistic regression and population attributable risk using familial standardized incidence ratio as the covariate. Chi-square test and logistic regression were used to evaluate birth order and maternal/paternal age at conception of the SSc proband. RESULTS: We found 1,947 unique SSc patients from UUHSC and UPDB. We selected 5 controls per case (n = 9,115), matched by birth year and sex. Mitochondrial inheritance analysis indicated no evidence to suggest SSc was associated with mitochondrial inheritance. Birth order and maternal/paternal age at conception analysis results show that they also do not significantly affect SSc development. CONCLUSION: Results suggest that although heritable risk of SSc is observed, mitochondrial inheritance, birth order, and parental age are not likely responsible for pathogenesis.

Increased risk of colorectal neoplasia among family members of patients with colorectal cancer: a population-based study in Utah.

BACKGROUND & AIMS: Colorectal cancer (CRC) frequently develops in multiple members of the same families, but more data are needed to prepare effective screening guidelines. We quantified the risk of CRC and adenomas in first-degree relatives (FDRs) and second-degree relatives and first cousins of individuals with CRC, and stratified risk based on age at cancer diagnosis. METHODS: We performed a case-control study of Utah residents, 50-80 years old, who underwent colonoscopy from 1995 through 2009. Index cases (exposed to colonoscopy) were colonoscopy patients with a CRC diagnosis. Age- and sex-matched individuals, unexposed to colonoscopy (controls) were selected to form the comparison groups for determining risk in relatives. Colonoscopy results were linked to cancer and pedigree information from the Utah Population Database to investigate familial aggregation of colorectal neoplasia using Cox regression analysis. RESULTS: Of 126,936 patients who underwent a colonoscopy, 3804 were diagnosed with CRC and defined the index cases. FDRs had an increased risk of CRC (hazard rate ratio [HRR], 1.79; 95% confidence interval [CI],1.59-2.03), as did second-degree relatives (HRR, 1.32; 95% CI, 1.19-1.47) and first cousins (HRR, 1.15; 95% CI, 1.07-1.25), compared with relatives of controls. This risk was greater for FDRs when index patients developed CRC at younger than age 60 years (HRR, 2.11; 95% CI, 1.70-2.63), compared with older than age 60 years (HRR, 1.77; 95% CI, 1.58-1.99). The risk of adenomas (HRR, 1.82; 95% CI, 1.66-2.00) and adenomas with villous histology (HRR, 2.43; 95% CI, 1.96-3.01) also were increased in FDRs. Three percent of CRCs in FDRs would have been missed if the current guidelines, which stratify screening recommendations by the age of the proband, were strictly followed. CONCLUSIONS: FDRs, second-degree relatives, and first cousins of patients who undergo colonoscopy and are found to have CRC have a significant increase in the risk of colorectal neoplasia. These data should be considered when establishing CRC screening guidelines for individuals and families.

Epidemiology and familial risk of synchronous and metachronous colorectal cancer: a population-based study in Utah.

BACKGROUND & AIMS: Patients diagnosed with colorectal cancer (CRC) are at risk for synchronous and metachronous lesions at the time of diagnosis or during follow-up evaluation. We performed a population-based study to evaluate the rate, predictors, and familial risk for synchronous and metachronous CRC in Utah. METHODS: All newly diagnosed cases of CRC between 1980 and 2010 were obtained from the Utah Cancer Registry and linked to pedigrees from the Utah Population Database. RESULTS: Of the 18,782 patients diagnosed with CRC, 134 were diagnosed with synchronous CRC (0.71%) and 300 were diagnosed with metachronous CRC (1.60%). The risk for synchronous CRC was significantly higher in men (odds ratio [OR], 1.45; 95% confidence interval [CI], 1.02-2.06) and in patients aged 65 years or older (OR, 1.50; 95% CI, 1.02-2.21). Synchronous CRCs were located more often in the proximal colon (OR, 1.70; 95% CI, 1.20-2.41). First-degree relatives of cases with synchronous (OR, 1.86; 95% CI, 1.37-2.53), metachronous (OR, 2.34; 95% CI, 1.62-3.36), or solitary CRC (OR, 1.75; 95% CI, 1.63-1.88) were at increased risk for developing CRC, compared with relatives of CRC-free individuals. Four percent of first-degree relatives of patients with synchronous or metachronous cancer developed CRC at younger ages than the age recommended for initiating CRC screening (based on familial risk), and therefore would not have been screened. CONCLUSIONS: Of patients diagnosed with CRC, 2.3% are found to have synchronous lesions or develop metachronous CRC during follow-up evaluation. Relatives of these patients have a greater risk of CRC than those without a family history of CRC. These results highlight the importance of obtaining a thorough family history and adhering strictly to surveillance guidelines during management of high-risk patients.

Survival of offspring who experience early parental death: early life conditions and later-life mortality.

We examine the influences of a set of early life conditions (ELCs) on all-cause and cause-specific mortality among elderly individuals, with special attention to one of the most dramatic early events in a child's, adolescent's, or even young adult's life, the death of a parent. The foremost question is, once controlling for prevailing (and potentially confounding) conditions early in life (family history of longevity, paternal characteristics (SES, age at time of birth, sibship size, and religious affiliation)), is a parental death associated with enduring mortality risks after age 65? The years following parental death may initiate new circumstances through which the adverse effects of paternal death operate. Here we consider the offspring's marital status (whether married; whether and when widowed), adult socioeconomic status, fertility, and later life health status. Adult health status is based on the Charlson Co-Morbidity Index, a construct that summarizes nearly all serious illnesses afflicting older individuals that relies on Medicare data. The data are based on linkages between the Utah Population Database and Medicare claims that hold medical diagnoses data. We show that offspring whose parents died when they were children, but especially when they were adolescents/young adults, have modest but significant mortality risks after age 65. What are striking are the weak mediating influences of later-life comorbidities, marital status, fertility and adult socioeconomic status since controls for these do little to alter the overall association. No beneficial effects of the surviving parent's remarriage were detected. Overall, we show the persistence of the effects of early life loss on later-life mortality and indicate the difficulties in addressing challenges at young ages.

Characteristics of missed or interval colorectal cancer and patient survival: a population-based study.

BACKGROUND & AIMS: Colorectal cancers (CRCs) diagnosed within a few years after an index colonoscopy can arise from missed lesions or the development of a new tumor. We investigated the proportion, characteristics, and factors that predict interval CRCs that develop within 6-60 months of colonoscopy. METHODS: We performed a population-based cohort study of Utah residents who underwent colonoscopy examinations from 1995 through 2009 at Intermountain Healthcare or the University of Utah Health System, which provide care to more than 85% of state residents. Colonoscopy results were linked with cancer histories from the Utah Population Database to identify patients who underwent colonoscopy 6-60 months before a diagnosis of CRC (interval cancer). Logistic regression was performed to identify risk factors associated with interval cancers. RESULTS: Of 126,851 patients who underwent colonoscopies, 2659 were diagnosed with CRC; 6% of these CRCs (159 of 2659) developed within 6 to 60 months of a colonoscopy. Sex and age were not associated with interval CRCs. A higher percentage of patients with interval CRC were found to have adenomas at their index colonoscopy (57.2%), compared with patients found to have CRC detected at colonoscopy (36%) or patients who did not develop cancer (26%) (P < .001). Interval CRCs tended to be earlier-stage tumors than those detected at index colonoscopy, and to be proximally located (odds ratio, 2.24; P < .001). Patients with interval CRC were more likely to have a family history of CRC (odds ratio, 2.27; P = .008) and had a lower risk of death than patients found to have CRC at their index colonoscopy (hazard ratio, 0.63; P < .001). CONCLUSIONS: In a population-based study in Utah, 6% of all patients with CRC had interval cancers (cancer that developed within 6 to 60 months of a colonoscopy). Interval CRCs were associated with the proximal colon, earlier-stage cancer, lower risk of death, higher rate of adenoma, and family history of CRC. These findings indicate that interval colorectal tumors may arise as the result of distinct biologic features and/or suboptimal management of polyps at colonoscopy.

Risk of colorectal cancer and adenomas in the families of patients with adenomas: a population-based study in Utah.

BACKGROUND: Guidelines recommend that individuals with a first-degree relative (FDR) diagnosed with colorectal cancer (CRC) or advanced adenoma before age 60 years should undergo colonoscopy starting at age 40 years. The authors quantified the risk of adenomas and CRC in FDRs, second-degree relatives (SDRs), and third-degree relatives (TDRs) of patients diagnosed with adenomas and advanced adenomas. METHODS: A population-based, retrospective, case-control study was performed of residents of the state of Utah aged 50 years to 80 years who underwent colonoscopy between 1995 and 2009 at Intermountain Healthcare or the University of Utah. Controls were selected from the population of colonoscopy patients who were free of adenomas or CRC and matched to each case based on sex and birth year. Colonoscopy results were linked with cancer and pedigree information from the Utah Population Database to investigate the familial aggregation of adenomas and CRC using Cox regression analysis. The unit of analysis was the relatives of cases and controls. RESULTS: Of 126,936 patients who underwent colonoscopy, 43,189 had adenomas and 5563 had advanced adenomas and defined the case population. An elevated risk of CRC was found in FDRs (relative risk [RR], 1.35; 95% confidence interval [95% CI], 1.25-1.46), SDRs (RR, 1.15; 95% CI, 1.07-1.23) of adenoma cases, and in FDRs of advanced adenoma cases (RR, 1.68; 95% CI, 1.29-2.18) compared with controls. Approximately 10% of CRCs diagnosed in relatives would have been missed if the current screening guidelines were strictly adhered to. CONCLUSIONS: Relatives of colonoscopy patients with adenomas and advanced adenomas appear to have a significantly elevated risk of developing colorectal neoplasia. These data should be considered when establishing CRC screening guidelines for individuals and their families.

Familial aggregation of childhood and adult cancer in the Utah genealogy.

A small proportion of childhood cancer is attributable to known hereditary syndromes, but whether there is any familial component to the remainder remains uncertain. We explored familial aggregation of cancer in a population-based case-control study using genealogical record linkage and designed to overcome limitations of previous studies. Subjects were selected from the Utah Population Database. We compared risk of cancer in adult first-degree relatives of children who were diagnosed with cancer with the risk in relatives of children who had not had a cancer diagnosed. We identified 1,894 childhood cancer cases and 3,788 controls; 7,467 relatives of cases and 14,498 relatives of controls were included in the analysis. Relatives of children with cancer had a higher risk of cancer in adulthood than relatives of children without cancer [odds ratio (OR) 1.31, 95% confidence interval (CI) 1.11-1.56]; this was restricted to mothers and siblings and was not evident in fathers. Familial aggregation appeared stronger among relatives of cases diagnosed before 5 years of age (OR 1.48, 95% CI 1.13-1.95) than among relatives of cases who were older when diagnosed (OR 1.22, 95% CI 0.98-1.51). These findings provide evidence of a generalized excess of cancer in the mothers and siblings of children with cancer. The tendency for risk to be higher in the relatives of children who were younger at cancer diagnosis should be investigated in other large data sets. The excesses of thyroid cancer in parents of children with cancer and of any cancer in relatives of children with leukemia merit further investigation.

The male-female health-survival paradox and sex differences in cohort life expectancy in Utah, Denmark, and Sweden 1850-1910.

PURPOSE: In Utah, the prevalence of unhealthy male risk behaviors are lower than in most other male populations, whereas women experience higher mortality risk because of higher fertility rates. Therefore, we hypothesize that the Utah sex differential in mortality would be small and less than in Sweden and Denmark. METHODS: Life tables from Utah, Denmark, and Sweden were used to calculate cohort life expectancies for men and women born in 1850-1910. RESULTS: The sex difference in cohort life expectancy was similar or larger in Utah when compared with Denmark and Sweden. The change over time in the sex differences in cohort life expectancy was approximately 2 years smaller for active Mormons in Utah than for other groups suggesting lifestyle as an important component for the overall change seen in cohort life expectancy. Sex differences in cohort life expectancy at the age of 50 years were similar for individuals actively affiliated with the Church of Jesus Christ of Latter-day Saints and for Denmark and Sweden. CONCLUSIONS: The hypothesis that a smaller sex difference in cohort life expectancies in Utah would be detected in relation to Denmark and Sweden was not supported. In Utah, the male-female differences in life expectancy remain substantial pointing toward biological mechanisms or other unmeasured risk factors.

Identifying clinical/translational research cohorts: ascertainment via querying an integrated multi-source database.

BACKGROUND: Ascertainment of potential subjects has been a longstanding problem in clinical research. Various methods have been proposed, including using data in electronic health records. However, these methods typically suffer from scaling effects-some methods work well for large cohorts; others work for small cohorts only. OBJECTIVE: We propose a method that provides a simple identification of pre-research cohorts and relies on data available in most states in the USA: merged public health data sources. MATERIALS AND METHODS: The Utah Population Database Limited query tool allows users to build complex queries that may span several types of health records, such as cancer registries, inpatient hospital discharges, and death certificates; in addition, these can be combined with family history information. The architectural approach incorporates several coding systems for medical information. It provides a front-end graphical user interface and enables researchers to build and run queries and view aggregate results. Multiple strategies have been incorporated to maintain confidentiality. RESULTS: This tool was rapidly adopted; since its release, 241 users representing a wide range of disciplines from 17 institutions have signed the user agreement and used the query tool. Three examples are discussed: pregnancy complications co-occurring with cardiovascular disease; spondyloarthritis; and breast cancer. DISCUSSION AND CONCLUSIONS: This query tool was designed to provide results as pre-research so that institutional review board approval would not be required. This architecture uses well-described technologies that should be within the reach of most institutions.

Total hip arthroplasty, hip osteoarthritis, total knee arthroplasty, and knee osteoarthritis in patients with developmental dysplasia of the hip and their family members: a kinship analysis report.

BACKGROUND: Developmental dysplasia of the hip (DDH) is a familial condition with a wide phenotypic expression. Families with high rates of DDH may have individuals with subtle phenotypic expression that can progress to osteoarthritis and require total hip arthroplasty (THA). This study compares the rates of THA in relatives of individuals with DDH with individuals in control families. METHODS: Probands with a diagnosis of DDH were identified using medical records linked to the Utah Population Database. Ten age-matched and sex-matched controls were randomly selected from a pool of unaffected individuals within the Utah Population Database. Diagnostic and procedural codes were used to determine the incidence of hip and knee osteoarthritis (HOA and KOA) and of THA and total knee arthroplasty (TKA) among the cases and controls and their relatives. Relative risks (RR) for HOA and KOA and for THA and TKA were calculated for the probands/controls and their family members. RESULTS: The RR of HOA was significantly increased in probands (RR=82.4; P<2e-16), their parents (R=2.22; P=0.0003), and in their grandparents (RR=1.33; P=0.011). The RR of THA was also significantly increased in probands (RR=1168; P <3e-08) and in their grandparents (RR=2.06; P=0.01). The RR of KOA was significantly increased in probands with a diagnosis of DDH (RR=20.96; P=2.2e-8) but not in their parents or grandparents. The RR of TKA was also increased in probands alone (RR=57.47; P=1.7e-05). CONCLUSIONS: Parents and grandparents of individuals with diagnosed DDH are significantly more likely to be diagnosed with HOA and undergo THA than members of the general population. These first-degree and second-degree relatives were not at higher risk for KOA or TKA. Given the known familial association of DDH, this association with osteoarthritis of the hip suggests a risk of undiagnosed hip dysplasia in individuals whose families have a high rate of DDH. LEVEL OF EVIDENCE: Level III.

Effects of BRCA1 and BRCA2 mutations on female fertility.

Women with BRCA1/2 mutations have a significantly higher lifetime risk of developing breast or ovarian cancer. We suggest that female mutation carriers may have improved fitness owing to enhanced fertility relative to non-carriers. Here we show that women who are carriers of BRCA1/2 mutations living in natural fertility conditions have excess fertility as well as excess post-reproductive mortality in relation to controls. Individuals who tested positive for BRCA1/2 mutations who linked into multi-generational pedigrees within the Utah Population Database were used to identify putative obligate carriers. We find that women born before 1930 who are mutation carriers have significantly more children than controls and have excess post-reproductive mortality risks. They also have shorter birth intervals and end child-bearing later than controls. For contemporary women tested directly for BRCA1/2 mutations, an era when modern contraceptives are available, differences in fertility and mortality persist but are attenuated. Our findings suggest the need to re-examine the wider role played by BRCA1/2 mutations. Elevated fertility of female mutation carriers indicates that they are more fecund despite their elevated post-reproductive mortality risks.

Hemangioma is associated with atopic disease.

OBJECTIVE: To determine if atopic disease is associated with infantile hemangioma. STUDY DESIGN: Case control study. SETTING: State of Utah inpatient and outpatient records obtained from the Department of Health, Intermountain Healthcare medical records, and the University of Utah Health Care medical records using the Utah Population Database. SUBJECTS: Patients given an International Classification of Diseases, Ninth Revision diagnosis of hemangioma prior to age 5 years, from 1991 to 2009. METHODS: Allergy, asthma, and eczema rates in the hemangioma cohort compared to randomly matched controls using logistic regression analysis. RESULTS: The authors identified 2063 patients in the hemangioma group. The overall odds ratio of atopic disease in patients diagnosed with hemangioma was 1.67 compared to the control group (P < .0001). In the hemangioma cohort, the authors found a 36% increased risk of allergies (P < .0001), 67% increased risk of asthma (P < 4e-12), and 82% increased risk of eczema (P < 2e-16). CONCLUSION: This study indicates that allergy, asthma, and eczema are positively associated with hemangioma. Eczema was most strongly associated with hemangioma, with a nearly 2-fold increased risk. Understanding the relationship between atopic disease and infantile hemangioma may elucidate the pathophysiology of each and ultimately lead to better treatment options.

Evaluation of record linkage between a large healthcare provider and the Utah Population Database.

OBJECTIVE: Electronically linked datasets have become an important part of clinical research. Information from multiple sources can be used to identify comorbid conditions and patient outcomes, measure use of healthcare services, and enrich demographic and clinical variables of interest. Innovative approaches for creating research infrastructure beyond a traditional data system are necessary. MATERIALS AND METHODS: Records from a large healthcare system's enterprise data warehouse (EDW) were linked to a statewide population database, and a master subject index was created. The authors evaluate the linkage, along with the impact of missing information in EDW records and the coverage of the population database. The makeup of the EDW and population database provides a subset of cancer records that exist in both resources, which allows a cancer-specific evaluation of the linkage. RESULTS: About 3.4 million records (60.8%) in the EDW were linked to the population database with a minimum accuracy of 96.3%. It was estimated that approximately 24.8% of target records were absent from the population database, which enabled the effect of the amount and type of information missing from a record on the linkage to be estimated. However, 99% of the records from the oncology data mart linked; they had fewer missing fields and this correlated positively with the number of patient visits. DISCUSSION AND CONCLUSION: A general-purpose research infrastructure was created which allows disease-specific cohorts to be identified. The usefulness of creating an index between institutions is that it allows each institution to maintain control and confidentiality of their own information.

Familial clustering of hemangiomas.

OBJECTIVES: To assess the degree of relationship among individuals with hemangiomas and to evaluate the relative risk (RR) for family members of individuals with hemangiomas. DESIGN: Retrospective case-control study. SETTING: Utah Population Database. PARTICIPANTS: Data sets of individuals of different ages with International Classification of Diseases, Ninth Revision (ICD-9) codes for hemangiomas were created from sources having medical records linked to the Utah Population Database. Controls were selected who matched cases for sex, birth year, and birthplace inside vs outside of Utah. Ten controls were selected per case, and sampling was performed without replacement. Kinship analysis tools were used to identify pedigrees having excess individuals with hemangiomas. MAIN OUTCOME MEASURE: Using conditional logistic regression analysis, RR for hemangiomas among several kinship classes was determined. RESULTS: Identified were 2514 distinct cases 12 years or younger with ICD-9 code 228.01, and the RR for sibs in this group was significantly increased (RR, 2.52; P < .001). Seventy-three founder families had 5 or more affected descendants with cluster P values ≤ .01; familial standardized incidence ratios ranged from 1.64 to 9.50. Family sizes ranged from 546 to 22 291 descendants. CONCLUSIONS: Sibs have increased RR for infantile hemangiomas, suggesting a potential genetic contribution to this likely multifactorial disease. Identification of large families with distantly related individuals will be helpful for future shared segment identification analyses.

Inflammatory bowel disease aggregation in Utah kindreds.

BACKGROUND: The observed heritability of inflammatory bowel disease (IBD) is incompletely explained by known genetic risk factors. Kindred-specific genetic variants that cause IBD may be a source of "missing heritability." Given that they have been previously difficult to identify, we sought to identify high-risk IBD kindreds. METHODS: We used a large population-based database--the Utah Population Database (UPDB)--which contains genealogical and healthcare data to characterize the risk of Crohn's disease (CD), ulcerative colitis (UC), and IBD in kindreds. We identified CD and UC cases using ICD-9 codes. We calculated the adjusted relative risk to relatives of affected individuals. We calculated the familial standardized incidence ratio (FSIR) to quantify the kindred-specific disease risk. RESULTS: In all, 3601 CD cases and 3976 UC cases met inclusion criteria. A total of 655 CD kindreds and 615 UC kindreds had a statistical excess of disease. Risk of disease varied among kindreds, with some kindreds demonstrating ≈ 20-fold elevated risk. For CD, UC, and IBD, relative risks were significantly elevated for first- and second-degree relatives and first cousins. The adjusted population attributable risks for familial CD, UC, and IBD were 0.20 (95% confidence interval [CI]: 0.17-0.23); 0.17 (0.14-0.21); and 0.19 (0.17-0.22), respectively. CONCLUSIONS: We identified multiple kindreds with a statistical excess of CD, UC, and IBD, and validated the UPDB as a resource for family studies in IBD. Given the need for novel genetic mapping strategies to explain the apparent missing heritability in IBD, further studies of these high-risk kindreds is justified.

The impact of a growing minority population on identification of duplicate records in an enterprise data warehouse.

Patient medical records are often fragmented across disparate healthcare databases, potentially resulting in duplicate records that may be detrimental to health care services. These duplicate records can be found through a process called record linkage. This paper describes a set of duplicate records in a medical data warehouse found by linking to an external resource containing family history and vital records. Our objective was to investigate the impact database characteristics and linkage methods have on identifying duplicate records using an external resource. Frequency counts were made for demographic field values and compared between the set of duplicate records, the data warehouse, and the external resource. Considerations for understanding the relationship that records labeled as duplicates have with dataset characteristics and linkage methods were identified. Several noticeable patterns were identified where frequency counts between sets deviated from what was expected including how the growth of a minority population affected which records were identified as duplicates. Record linkage is a complex process where results can be affected by subtleties in data characteristics, changes in data trends, and reliance on external data sources. These changes should be taken into account to ensure any anomalies in results describe real effects and are not artifacts caused by datasets or linkage methods. This paper describes how frequency count analysis can be an effective way to detect and resolve anomalies in linkage results and how external resources that provide additional contextual information can prove useful in discovering duplicate records.

Quantification of the familial contribution to juvenile idiopathic arthritis.

OBJECTIVE: We previously demonstrated that there is familial aggregation of juvenile idiopathic arthritis (JIA). Using a large JIA cohort, we sought to identify additional clusters of JIA cases and to calculate robust estimates of the relative risk (RR) of JIA in the siblings and cousins of JIA probands. We also estimated the population attributable risk (PAR) of familial factors in JIA. METHODS: A probabilistic record-linking analysis was performed by matching the records of 862 patients with JIA with the records of approximately 7 million individuals in the Utah Population Database (UPDB), a computerized genealogic database. For each patient, 5 control subjects matched for birth year and sex were selected from the UPDB. Specialized software was used to test for familial aggregation of disease, to estimate the magnitude of familial risks, and to identify families at high risk of disease. RESULTS: We identified 22 founders who had significantly more descendants with JIA than expected (5-13 descendants; P values ranged from <0.0001 to <0.008). The PAR of familial factors for JIA was approximately 13%. The RR of JIA in the siblings of patients was significantly increased (11.6, 95% confidence interval [95% CI] 4.9-27.5, P < 2.59 x 10(-8)). The RR of JIA in first cousins was also increased (5.82, 95% CI 2.5-13.8, P < 6.07 x 10(-5)). CONCLUSION: We have identified the largest sets of JIA pedigrees described to date. Approximately 13% of cases of JIA can be attributed to familial factors. Siblings and first cousins of probands with JIA have an increased risk of JIA. The observed decline in the magnitude of risk between siblings and cousins suggests that JIA is influenced by shared genetic factors.

Heritability of vasculopathy, autoimmune disease, and fibrosis in systemic sclerosis: a population-based study.

OBJECTIVE: To investigate the familiality of systemic sclerosis (SSc) in relation to Raynaud's phenomenon (RP) (a marker of vasculopathy), other autoimmune inflammatory disease, and fibrotic interstitial lung disease (ILD). METHODS: A genealogic resource, the Utah Population Database (UPDB), was used to test heritability of RP, other autoimmune disease, and ILD. Diseases were defined by International Classification of Diseases, Ninth Revision codes and identified from statewide discharge data, the University of Utah Health Science Center Enterprise Data Warehouse, and death certificates and were linked to the UPDB for analysis. Familial standardized incidence ratio (FSIR), relative risks (RRs) to first-, second-, third-, and fourth-degree relatives for SSc, RP, other autoimmune disease, and ILD (with 95% confidence intervals [95% CIs]), and population attributable risk (PAR) were calculated. RESULTS: A software kinship analysis tool was used to analyze 1,037 unique SSc patients. Fifty SSc families had significant FSIRs, ranging from 2.07 to 17.60. The adjusted PAR was approximately 8%. The RRs were significant for other autoimmune disease in the first-degree relatives (2.49 [95% CI 1.99-3.41], P = 2.42 x 10(-15)) and second-degree relatives (1.48 [95% CI 1.34-2.39], P = 0.002), for RP in first-degree relatives (6.38 [95% CI 3.44-11.83], P = 4.04 x 10(-9)) and second-degree relatives (2.39 [95% CI 1.21-4.74], P = 0.012), and for ILD in first-degree relatives (1.53 [95% CI 1.04-2.26], P = 0.03), third-degree relatives (1.47 [95% CI 1.18-1.82], P = 0.0004), and fourth-degree relatives (1.2 [95% CI 1.06-1.35], P = 0.004). CONCLUSION: These data suggest that SSc pedigrees include more RP, autoimmune inflammatory disease, and ILD than would be expected by chance. In SSc pedigrees, genetic predisposition to vasculopathy is the most frequent risk among first-degree relatives.