Biomedical subjects

Cynthia S Crowson

Publications and source records attributed to Cynthia S Crowson.

32 records · Page 2Linked to original sources

PubMed2003

Relative contributions of bone density, bone turnover, and clinical risk factors to long-term fracture prediction.

Long-term fracture prediction using bone mineral density remains controversial, as does the additional contribution from assessing bone turnover or clinical risk factors. We measured bone mineral density at various sites, along with biochemical markers of bone turnover, sex steroid levels, and over 100 clinical variables, at baseline on an age-stratified sample of 304 Rochester, MN women in 1980. The 225 postmenopausal women were subsequently followed for 3146 person-years (median, 16.2 years per subject), wherein they experienced 302 new fractures: 81% resulted from minimal or moderate trauma and 60% of these involved the proximal femur, thoracic or lumbar vertebrae, or distal forearm. Accounting for multiple fractures per subject, these osteoporotic fractures together were best predicted by baseline femoral neck bone mineral density (age-adjusted hazard ratio [HR] per SD decrease, 1.37; 95% CI, 1.10-1.70); 19 moderate trauma forearm fractures were best predicted by distal radius bone mineral content, whereas 28 hip fractures and 100 vertebral fractures were best predicted by femoral neck bone mineral density. Femoral neck bone mineral density performed comparably in predicting osteoporotic fracture risk within the first decade of follow-up (HR, 1.38; 95% CI, 1.10-1.74) as well as more than 10 years after baseline (HR, 1.39; 95% CI, 1.05-1.84). The older biochemical markers were not associated with fractures, but serum "free" estradiol index was independently predictive of short- and long-term fracture risk. Consistent clinical risk factors were not identified, but statistical power was limited. Identifying patients at increased long-term risk of fracture is challenging, but it is reassuring that femoral neck bone mineral density can predict osteoporotic fractures up to 20 years later.

Age Factors↗

PubMed2003

Long-term survival of patients with anorexia nervosa: a population-based study in Rochester, Minn.

OBJECTIVE: To estimate long-term survival of unselected patients with anorexia nervosa from Rochester, Minn. PATIENTS AND METHODS: In this population-based retrospective cohort study, all 208 Rochester residents who presented with anorexia nervosa (193 women and 15 men) for the first time from 1935 through 1989 were monitored for up to 63 years. Subsequent survival was compared with that expected for Minnesota white residents of similar age and sex, and standardized mortality ratios were determined on the basis of age- and sex-specific death rates for the US population in 1987. RESULTS: Survival was not worse than expected in this cohort (P = .16). The estimated survival 30 years after the initial diagnosis of anorexia nervosa was 93% (95% confidence interval, 88%-97%) compared with an expected 94%. During 5646 person-years of follow-up (median, 22 years per patient), 17 deaths occurred (14 women and 3 men) compared with an expected 23.7 deaths (standardized mortality ratio, 0.71; 95% confidence interval, 0.42-1.09). One woman died of complications of anorexia nervosa, 2 women committed suicide, and 6 patients (5 women and 1 man) died of complications of alcoholism. Other causes of death were not increased. CONCLUSIONS: Long-term survival of Rochester patients with anorexia nervosa did not differ from that expected. This finding suggests that overall mortality was not increased among the spectrum of cases representative of the community.

Adolescent↗

PubMed2003

Risk of breast cancer and breast cancer characteristics in women treated with supradiaphragmatic radiation for Hodgkin lymphoma: Mayo Clinic experience.

OBJECTIVE: To evaluate the overall risk of breast cancer and breast cancer characteristics in women given supradiaphragmatic radiation therapy for Hodgkin lymphoma. PATIENTS AND METHODS: Medical records of 653 female patients who received supradiaphragmatic radiation therapy for Hodgkin lymphoma at the Mayo Clinic in Rochester, Minn, between 1950 and 1993 were abstracted, and follow-up questionnaires were mailed. In 4 patients, breast cancer was diagnosed before Hodgkin lymphoma was discovered. RESULTS: The median age of 649 patients at supradiaphragmatic radiation therapy was 31.8 years (range, 2.6-86.5 years). The median duration of follow-up was 8.7 years (range, < 1-47.9 years). In 30 patients, breast cancer developed (bilaterally in 4 patients) after supradiaphragmatic radiation therapy; the median interval was 19.9 years (range, 0.7-423 years). The median age at breast cancer diagnosis was 44.4 years (range, 27.5-70.8 years). The standardized morbidity ratio for breast cancer after supradiaphragmatic radiation therapy was 2.9 (95 % confidence interval [CI], 2.0-4.2) (P < .001). Breast cancer risk significantly increased 15 to 30 years after patients received supradiaphragmatic radiation therapy, and risk was inversely related to age at supradiaphragmatic radiation therapy until age 30 years. The standardized morbidity ratio for patients younger than 30 years at supradiaphragmatic radiation was 8.5 (95% CI, 53-13.1) vs 1.2 (95% CI, 0.5-2.2) for those aged 30 years or older (P < .001). Splenectomy increased breast cancer risk (P = .01). Breast cancer detection was by self-examination in 15 cancers, by mammography in 13, and by clinical examination in 4; in 2 cancers, the mode of detection was unknown. Modified radical mastectomy was used to treat breast cancer. CONCLUSION: The increased risk of breast cancer in survivors of Hodgkin lymphoma given supradiaphragmatic radiation therapy appears to be limited to patients who are younger than 30 years at radiation therapy or to those who have undergone splenectomy.

Adult↗

PubMed2002

Osteoporosis intervention following distal forearm fractures: a missed opportunity?

BACKGROUND: Fractures are a manifestation of osteoporosis, but therapeutic interventions to reduce the risk of recurrent fractures are not widespread. OBJECTIVE: To identify predictors of osteoporosis treatment in postmenopausal women following distal forearm fracture. METHODS: This population-based retrospective cohort study included all postmenopausal women, 45 years or older, residing in Olmsted County, Minnesota, who sustained a distal forearm fracture due to minimal trauma (a fall from standing height or under) in 1993 to 1997. Complete medical records were reviewed for each subject and Cox proportional hazards regression was used to evaluate the relationship of baseline demographic and clinical characteristics to therapeutic interventions for osteoporosis within 12 months following the fracture. RESULTS: A total of 343 women with a mean age of 70.5 years had a minimal trauma distal forearm fracture. Within 12 months, 83% had seen a nonorthopedic physician. Of these, 17% had a pharmacologic osteoporosis intervention and the 12-month actuarially estimated cumulative incidence of any intervention was 18% (95% confidence interval [CI], 14%-22%). In a multivariate analysis, treatment was more likely to be offered to those with a prior diagnosis of osteoporosis (relative risk [RR], 2.08; 95% CI, 1.21-3.58), previous distal forearm fracture (RR, 2.38; 95% CI, 1.30-4.34), or history of cigarette smoking (RR, 1.86; 95% CI, 1.11-3.12). CONCLUSIONS: Effective osteoporosis interventions are underutilized among postmenopausal women who experience an osteoporotic fracture. Further work is needed to overcome barriers to optimal osteoporosis management in these women who are at high risk for future complications of osteoporosis.

Cohort Studies↗

PubMed2002

Frequency of infection in patients with rheumatoid arthritis compared with controls: a population-based study.

OBJECTIVE: A high frequency of infections complicating rheumatoid arthritis (RA) has been described in reports of case series. This retrospective longitudinal cohort study was undertaken to compare the frequency of infections in a population-based incidence cohort of RA patients with that in a group of individuals without RA from the same population. METHODS: RA patients included all members of an incidence cohort of Rochester, Minnesota residents ages >or=18 years who were first diagnosed as having RA between 1955 and 1994. One age- and sex-matched subject without RA was selected for each patient with RA. Study subjects were followed up by review of their entire medical record until death, migration from the area, or study end (January 1, 2000), and details of all documented infections, along with information on potential risk factors for infection, were recorded. Hazard ratios for infections were estimated using stratified Andersen-Gill proportional hazards models, with adjustment for potential confounders. RESULTS: The 609 RA patients and 609 non-RA study subjects (mean age 58.0 years; 73.1% female) were followed up for a mean of 12.7 years and 15.0 years, respectively, reflecting higher mortality among the group with RA. Hazards ratios for objectively confirmed infections, infections requiring hospitalization, and any documented infection in patients with RA were 1.70 (95% confidence interval [95% CI] 1.42-2.03), 1.83 (95% CI 1.52-2.21), and 1.45 (95% CI 1.29-1.64), respectively, after adjustment for age, sex, smoking status, leukopenia, corticosteroid use, and diabetes mellitus. Sites of infection with the highest risk ratios were bone, joints, skin, soft tissues, and the respiratory tract. CONCLUSION: In this study, patients with RA were at increased risk of developing infections compared with non-RA subjects. This may be due to immunomodulatory effects of RA, or to agents with immunosuppressive effects used in its treatment.

Arthritis, Rheumatoid↗

PubMed2002

Predictors of infection in rheumatoid arthritis.

OBJECTIVE: Patients with rheumatoid arthritis (RA) have been shown to have an increased susceptibility to the development of infections. The exact causes of this increased risk are unknown, but may relate to immunologic disturbances associated with the disease or to the immunosuppressive effects of agents used in its treatment. This study was undertaken to identify predictors of serious infections among patients with RA. Identification of such factors is the necessary first step in reducing the excess risk of infection in RA. METHODS: Members of a population-based incidence cohort of Rochester, Minnesota residents ages >or=18 years, who had been diagnosed with RA between 1955 and 1994, were followed up longitudinally through their complete medical records until January 1, 2000. We examined potential risk factors for the development of all objectively confirmed (by microbiology or radiology) infections and for infections requiring hospitalization. Potential risk factors included RA severity measures (rheumatoid factor positivity, elevated erythrocyte sedimentation rate, extraarticular manifestations of RA, and functional status), comorbidities (diabetes mellitus, alcoholism, and chronic lung disease), and other risk factors for infection (presence of leukopenia, smoking). Predictors were identified using multivariate time-dependent Cox proportional hazards modeling. RESULTS: The 609 RA patients in the cohort had a total followup time of 7,729.7 person-years (mean 12.7 years per patient). A total of 389 patients (64%) had at least 1 infection with objective confirmation, and 290 (48%) had at least 1 infection requiring hospitalization. Increasing age, presence of extraarticular manifestations of RA, leukopenia, and comorbidities (chronic lung disease, alcoholism, organic brain disease, and diabetes mellitus), as well as use of corticosteroids, were strong predictors of infection (P < 0.004) in both univariate and multivariate analyses. Notably, use of disease-modifying antirheumatic drugs was not associated with increased risk of infection in multivariate analyses, after adjustment for demographic characteristics, comorbidities, and disease-related variables. CONCLUSION: We identified a number of strong predictors of infections in a population-based cohort of patients with RA. These results can be used to prospectively identify high-risk patients, who may benefit from closer followup and implementation of preventive strategies.

Adrenal Cortex Hormones↗

PubMed2002

Trends in incidence and mortality in rheumatoid arthritis in Rochester, Minnesota, over a forty-year period.

OBJECTIVE: To determine time trends in the epidemiology of rheumatoid arthritis (RA) in a population-based cohort. METHODS: An inception cohort of residents of Rochester, Minnesota > or = 18 years of age who first fulfilled the American College of Rheumatology 1987 criteria between January 1, 1955 and December 31, 1994 (applied retrospectively, as appropriate) was assembled and followed up until January 1, 2000. Incidence rates were estimated and were age- and sex-adjusted to the 1990 white population of the US. A birth cohort analysis was performed, and survival rates over time were examined. RESULTS: The incidence cohort comprised 609 patients, 445 (73.1%) of whom were female and 164 (26.9%) were male, with a mean age at incidence of 58.0 years. The overall age- and sex-adjusted annual incidence of RA among Rochester, Minnesota, residents > or = 18 years of age was 44.6/100,000 population (95% confidence interval 41.0-48.2). While the incidence rate fell progressively over the 4 decades of study, from 61.2/100,000 in 1955-1964, to 32.7/100,000 in 1985-1994, there were indications of cyclical trends over time. Birth cohort analysis showed diminishing incidence rates through successive cohorts following a peak in the 1880-1890 cohorts. Incidence rates increased with age until age 85, but peaked earlier in women than in men. The survival rate in RA patients was significantly lower than the expected rate in the general population (P < 0.001), and no improvement was noted over time. CONCLUSION: The secular trends demonstrated in this study population, including the progressive decline in the incidence of RA over the last 40 years, suggest that an environmental factor may play a role in the etiology of RA.

Adult↗

PubMed2002

Long-term fracture risk in patients with Crohn's disease: a population-based study in Olmsted County, Minnesota.

BACKGROUND & AIMS: Osteoporosis is common in patients with Crohn's disease, but less is known about their risk of actual fractures. METHODS: The medical records of all 238 Olmsted County, Minnesota, residents diagnosed with Crohn's disease between 1940 and 1993 were reviewed for evidence of subsequent fractures compared with a control group of county residents matched by age and sex. The risk ratio of fracture in patients relative to controls was estimated using the Cox proportional hazards regression model. The cumulative incidence of fracture following diagnosis was estimated using the Kaplan-Meier method. RESULTS: Sixty-three patients had 117 different fractures. The cumulative incidence of any fracture from the time of diagnosis onward was 36% at 20 years versus 32% in controls (P = 0.792). Compared with controls, the overall risk ratio for any fracture was 0.9 (95% confidence interval [CI], 0.6-1.4), whereas the relative risk for an osteoporotic fracture was 1.4 (95% CI, 0.7-2.7). The risk ratio for thoracolumbar vertebral fracture was 2.2 (95% CI, 0.9-5.5). Cox proportional hazards regression identified only age as a significant clinical predictor of fracture risk (hazard ratio per 10-year increase in age, 1.3; 95% CI, 1.1-1.5). Specifically, use of corticosteroids and surgical resection did not predict risk of fracture among these unselected patients with Crohn's disease from the community. CONCLUSIONS: In this population-based inception cohort of patients with Crohn's disease, the risk of fracture was not elevated relative to age- and sex-matched controls.

Adolescent↗

PubMed2002

A population based assessment of the use of orthopedic surgery in patients with rheumatoid arthritis.

OBJECTIVE: To describe the use of orthopedic surgery, including joint replacement surgery, in a well defined population based cohort of patients with rheumatoid arthritis (RA) and to identify characteristics that predict such use. METHODS: A retrospective medical record review was performed of cases of RA incident in Rochester, MN, during the years 1955-85. Patients were followed until 1998. All joint surgeries were recorded, including joint reconstructive surgeries, total joint arthroplasty (TJA), and other joint reconstructive procedures (JRP) such as tendon transfers and resections, joint fusions, and surgeries for fractures and infections involving joints. RESULTS: Of the total 424 RA incident cases, 148 (34.9%) patients underwent one or more (maximum of 20/patient) surgical procedures involving joints during their followup (median 14.8 yrs, range 0.2-42.8 yrs). Overall, this RA cohort had 9.7 surgeries per 100 person-yrs of followup. The estimated cumulative incidence of surgical procedures for RA at 30 yrs was 52.7% +/- SE 4.2. Surgeries for arthritis related joint disease of RA included: primary TJA 76 patients (31.3 +/- 4.1); JRP joint fusion 78 patients (29.4 +/- 3.5); JRP soft tissue 92 patients (29.8 +/- 3.3); and cervical spine fusion one patient. Non-RA (trauma and other) joint surgeries included TJA 26 patients (13.5 +/- 3.4) and arthrotomy for septic arthritis 8 patients (2.4 +/- 0.9). Based on Cox proportional hazards regression, the risk of having a disease related joint surgery for RA is increased in patients who are younger (p < 0.001), have positive rheumatoid factor (p = 0.01), and those with rheumatoid nodules (p < 0.001). There was a borderline significant increase in the risk of first joint surgery in women (p = 0.09). Women also had significantly more joint surgeries (11.5/100 person-yrs) than men (4.9/100 person-yrs; p < 0.001). Survival of patients who had surgery for RA related joint disease was similar to those who did not. CONCLUSION: This is the first population based assessment of joint surgeries performed in patients with RA. Reconstructive surgeries were common, and women had significantly more surgeries than men. Survivorship among patients with RA undergoing surgeries was similar to that of the RA patient population at large.

Adult↗

PubMed2002

Occurrence of extraarticular disease manifestations is associated with excess mortality in a community based cohort of patients with rheumatoid arthritis.

OBJECTIVE: To investigate the occurrence of extraarticular manifestations (ExRA) in a well defined community based cohort of patients with rheumatoid arthritis (RA), and to examine their effect on mortality. METHODS: Using the resources of the Rochester Epidemiology Project, a retrospective medical record review was conducted of a cohort of 424 cases of RA in Olmsted County, MN, USA, diagnosed during the period 1955-1985. These cases had been classified using the American College of Rheumatology 1987 criteria for RA. Patients were followed 1955-1998 (median followup 14.8 yrs; range 0.2-42.8 yrs), and incident ExRA manifestations were recorded according to predefined criteria. Data on comorbidities were extracted using the definitions of the Charlson comorbidity index. Survival was compared to the general population using Kaplan-Meier estimates. RESULTS: ExRA occurred in 169 patients, corresponding to an incidence rate of 3.67/100 person-yrs. Compared to the general population, survival among patients with RA was decreased. Survival among patients with ExRA was markedly decreased compared to the general population and to patients without ExRA (p < 0.001). A particularly poor prognosis was noted in a subgroup of 63 patients (incidence rate 1.04/100 person-yrs) who fulfilled predefined criteria for severe ExRA (i.e., vasculitis, pericarditis, pleuritis, and/or Felty's syndrome). For RA patients who did not fulfill these criteria, there was no significant increase of mortality (p = 0.09). In a multivariate model of mortality, including age, sex, and the presence of known comorbidities, the presence of one or more of these ExRA was the strongest predictor of mortality. CONCLUSION: In this first community based study of extraarticular manifestations in RA, virtually all the excess mortality occurred in a subgroup of patients with severe extraarticular disease, suggesting that extraarticular disease is the major predictor of mortality in patients with RA.

Age Factors↗

PubMed2002

Risk factors for the development of psoriatic arthritis: a population based nested case control study.

OBJECTIVE: To identify factors influencing the development of psoriatic arthritis (PsA) in a population-based, inception cohort of psoriasis (PS) patients. METHODS: Using the population-based data resources of the Rochester Epidemiology Project. which ensures virtually complete ascertainment of all clinically defined conditions, we previously identified all incident cases of PsA and prevalent cases with PS from 1/1/1982 to 12/21/1991. In this nested case-control study, we assessed potential factors influencing the development of PsA in this cohort using medical record and patient survey information. Each case of PsA was matched with 2 PS controls on age, gender and PS duration/date of onset. Factors influencing the development of PsA were identified, adjusting for the influence of other variables using conditional logistic regression for medical record data and logistic regression for survey data. RESULTS: Sixty incident PsA cases were matched with 120 controls with PS. The median age at onset of PS was 31.7 (3.0-78.3) years, and 49% of subjects were male. There were 67% (n = 40) survey responders among cases and 48% (n = 58) among controls. Corticosteroids were used by 10 cases and 6 controls in the 2 years prior to onset of PS through to the development of PsA, and increased the risk of developing PsA (odds ratio 4.33, 95% CI = 1.34-14.02). Pregnancy occurred in 2 cases and 12 controls in the same period, and decreased the risk of developing PsA (odds ratio 0.19, 95% CI = 0.04-0.95). These associations remained significant after adjusting for the influence of gender, age, and duration of psoriasis. CONCLUSION: Corticosteroid use and pregnancy, both of which modulate the immune response, may influence the development of PsA in patients with PS.

Adolescent↗

PubMed2002

Osteopenia in adults with a history of juvenile rheumatoid arthritis. A population based study.

OBJECTIVE: To determine the extent of osteopenia in a population based cohort of adults with a history of juvenile rheumatoid arthritis (JRA). METHODS: The Rochester Epidemiology Project database was used to identify all cases of JRA diagnosed among Rochester, Minnesota residents under the age of 16 years between January 1, 1960, and December 31, 1993. Thirty-two of the 57 adult patients in this population based cohort (ages 19-53 years, mean 35) participated in this study. Average length of followup from the time of diagnosis was 27.1 years (median 26.9, range 7.7-39.1). Dual energy x-ray absorptiometry scans were used to assess bone density of the lumbar spine, hip, distal one-third radius, and whole body. In addition, a number of variables that influence bone mass were analyzed. RESULTS: Although many participants had T scores within the normal range (T score > -1) at all measured sites, 41% (n = 13) were osteopenic (T score < or = -1) at either the lumbar spine or femoral neck. Twenty-eight percent (n = 9) had T scores < or = -1 in the lumbar spine (p = 0.058 relative to expected). Thirty-two percent (n = 10) had T scores < or = -1 in the femoral neck (p = 0.012 relative to expected). Several variables were significantly (p < 0.05) associated with low bone density in this cohort of adults with a history of JRA, including: (1) revised Steinbrocker functional class > or = 2 during adolescence, indicating poorer physical functioning; (2) lack of participation in organized sports during adolescence (a surrogate measure of physical activity); (3) tobacco use during adolescence; and (4) lower calcium intake during adolescence. CONCLUSION: Although many adults with a history of JRA have normal bone density, a substantial subset are osteopenic, placing them at increased risk of fractures later in life. This observation is particularly striking given the predominance of patients with pauciarticular JRA in this population based group. We identified several variables associated with osteopenia in this cohort. Further work is needed to identify those patients with JRA who may benefit from aggressive therapy targeted at preventing the longterm morbidity associated with osteopenia.

Absorptiometry, Photon↗

PubMed2002

Trends in the incidence of polymyalgia rheumatica over a 30 year period in Olmsted County, Minnesota, USA.

OBJECTIVE: To determine time trends in the incidence and survival of polymyalgia rheumatica (PMR) over a 30 year period in Olmsted County, Minnesota, USA. METHODS: Using the unified medical record linkage system of the Rochester Epidemiology Project, we identified all incident cases of PMR among residents of Olmsted County, MN, between January 1, 1970, and December 31, 1999. Incidence rates were estimated and age- and sex-adjusted to the 1990 US white population. The annual incidence rates were graphically illustrated using a 3 year centered moving average. A Poisson regression model was used to evaluate predictors of PMR incidence. Survival rates were computed and compared with the expected rates in the population. RESULTS: There were 378 incident cases of PMR during the 30 year study period. Of these 66.6% were female and the mean age at incidence was 72.8 years. The overall age and sex adjusted annual incidence of PMR per 100,000 population aged > or = 50 years was 58.7 (95% CI 52.8,64.7). Incidence rates increased with age in both sexes, but in women, unlike in men, incidence fell after age 80. The incidence rates varied over the period of observation, but no significant trends over time were found. In the multivariable analysis, sex (p = 0.023), age (p < 0.001), and age2 (p < 0.001), but not calendar year (p = 0.24) were significant predictors of incidence. Survival among individuals with PMR was not significantly different from that expected in the population (p = 0.06). CONCLUSION: The incidence of PMR has remained relatively stable over the past 30 years.

Aged↗

PubMed2002

Epidemiology of gout: is the incidence rising?

OBJECTIVE: To determine whether the incidence of gout is higher in 1995-1996 compared to 1977-1978. METHODS: Using the Rochester Epidemiology Project computerized medical record system, all potential cases of acute gout in the city of Rochester, Minnesota during the time intervals of 1977-1978 and 1995-1996 were identified. The complete medical records of all potential cases were screened and all who fulfilled the 1977 American College of Rheumatology proposed criteria for gout were included as incidence cases. Demographic data, body mass index, clinical presentation, and associated comorbid conditions were abstracted. The overall and age-gender adjusted incidence rates from the 2 cohorts were calculated and compared. RESULTS: A total of 39 new cases of acute gout were identified during the 2 year interval 1977-1978 representing an age and sex-adjusted annual incidence rate of 45.0/100,000 (95% CI: 30.7, 59.3). For the interval 1995-1996, 81 cases were diagnosed, representing an annual incidence rate of 62.3/100,000 (95% CI: 48.4, 76.2). There was a greater than 2-fold increase in the rate of primary gout (i.e., no history of diuretic exposure) in the recent compared to the older time periods (p = 0.002). The incidence of secondary, diuretic related gout did not increase over time (p = 0.140). CONCLUSION: Our results indicate that the incidence of primary gout has increased significantly over the past 20 years. While this increase might be a result of improved ascertainment of atypical gout, it may also be related to other, as yet unidentified, risk factors.

Adrenal Cortex Hormones↗