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J F Fries

Publications and source records attributed to J F Fries.

At least 73 records · Page 4Linked to original sources
PubMed1993

A reevaluation of aspirin therapy in rheumatoid arthritis.

BACKGROUND: Aspirin therapy has been largely superseded by prescription nonsteroidal anti-inflammatory drug (NSAID) therapy in rheumatoid arthritis, in part because of premarketing studies suggesting lesser toxic effects for NSAIDs than for aspirin. This study evaluates these toxic effects in a postmarketing population of patients with rheumatoid arthritis. METHODS: We studied 1521 consecutive courses of aspirin and 4860 courses of NSAIDs in patients with rheumatoid arthritis from eight Arthritis, Rheumatism, and Aging Medical Information System Post-marketing Surveillance Centers. Toxicity index scores were generated from symptoms, laboratory abnormalities, and hospitalizations, weighted for variable severity and severity of side effect. RESULTS: The toxicity index was only 1.37 (SE = 0.10) for aspirin and 1.87 to 2.90 for selected nonsalicylate NSAIDs. These differences were consistent across centers and remained after statistical adjustment for differing patient characteristics. There was a different toxicity with different aspirin preparations, with a score for plain aspirin of 1.36 (SE = 0.23), for buffered aspirin of 1.10 (0.20), and for enteric-coated aspirin preparations of 0.92 (0.14). Most important, there were strong dose effects, with a score of 0.73 (0.09) for 651 to 2600 mg daily, 1.08 (0.17) for 2601 to 3900 mg, and 1.91 (0.38) for more than 3900 mg. The average aspirin dose taken was only 2665 mg/d, approximately eight "tablets," compared with 3600 to 4800 mg/d used in the 16 pivotal premarketing studies reviewed. Average NSAID doses were, on the other hand, lower in premarketing trials (eg, naproxen 500 mg/d vs 773 mg/d in the Arthritis, Rheumatism, and Aging Medical System clinical practices). CONCLUSIONS: Aspirin therapy, in doses commonly employed in practice, has an excellent safety profile in rheumatoid arthritis, and it is the least costly NSAID. The safety advantage is explained primarily by a dose effect and secondarily by possible differences between formulations. Newer management strategies for rheumatoid arthritis emphasize NSAID use as symptomatic therapy and use of disease-modifying anti-rheumatic drug therapy for anti-inflammatory objectives. Thus, the original recommendation for "anti-inflammatory" doses of aspirin now is less easily justified. Aspirin therapy merits reconsideration as adjunctive therapy for the management of rheumatoid arthritis.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1993

Progression of functional disability in patients with rheumatoid arthritis. Associations with rheumatology subspecialty care.

BACKGROUND: To determine whether patients with rheumatoid arthritis and their physicians make appropriate decisions regarding referral to rheumatologists and the need for continuing rheumatology care, we examined the relationship between the progression of functional disability in these patients and their use of rheumatology subspecialty care over time. METHODS: A cohort of 282 patients with rheumatoid arthritis was followed prospectively for up to 10 years. Participants were categorized into three subgroups based on the pattern of care received from rheumatologists over the study period: patients who were never treated by a rheumatologist; patients treated by a rheumatologist only intermittently; and patients treated by a rheumatologist at least once during each 6-month study period. The outcome was the rate of progression of functional disability, measured using the Health Assessment Questionnaire Disability Index. RESULTS: Among the 52 patients who had not been referred to a rheumatologist, 30 (58%) had rates of progression of functional disability that were stable or improving over time (rate < 0.01 Disability Index units per year), while 22 (42%) had rates that were worsening (rate > or = 0.01 Disability Index units per year). Among patients treated by rheumatologists, the average rate of progression was substantially lower among the 69 patients who were treated regularly by a rheumatologist than among 161 patients treated by rheumatologists intermittently (0.008 Disability Index units per year vs 0.020 Disability Index units per year). This difference was associated with more intensive use of second-line antirheumatic medications, and more frequent joint surgeries, among patients treated by rheumatologists on a regular basis. CONCLUSIONS: Most patients with rheumatoid arthritis in this community cohort were treated by a rheumatologist, but 42% of those not referred had progressively increasing functional disability. Among patients treated by rheumatologists, those who had continuing care from rheumatologists experienced lower rates of progression of functional disability than those who had only intermittent care. These results suggest that use of rheumatology subspecialty care is associated with better health outcomes in rheumatoid arthritis.

Activities of Daily Living↗
PubMed1993

Reducing attrition bias with an instrumental variable in a regression model: results from a panel of rheumatoid arthritis patients.

This study proposes an econometric technique to reduce attrition bias in panel data. In the simplest case, one estimates two regressions. The first is a probit regression based on sociodemographic and clinical characteristics measured at baseline. The probit regression estimates the probability that subjects stay or leave over the duration of the study. We insert the predicted probabilities from the probit regression into an inverse Mills ratio (IMR) or hazard rate to form an instrumental variable. We use this instrumental variable subsequently as an additional covariate in a second regression model that attempts to explain fluctuations in the dependent variable. The second regression, which is linear, includes only subjects who remained in the study. In alternative models, instrumental variables are created using predicted values from least squares and logit regressions estimating the probability that subjects stay or leave. The use of the instrumental variables reduces the effects of attrition bias in the linear regression model. We applied the technique to a panel of patients with rheumatoid arthritis (RA) enrolled in 1981 and followed through 1990. We attempted to predict values for a measure of functional disability recorded in 1990 with use of covariates measured in 1981. The dependent variable was an index of disability in 1990 and the independent variables (covariates) included the disability index from 1981, the years of duration of RA, gender, marital status, education, and age in 1981. The correction technique suggested that ignoring attrition bias would underestimate the strength of associations between being female and the subsequent disability index, and overestimate the strength of associations between being married spouse present, age, and the initial disability index on the one hand and the subsequent disability index on the other.

Age Factors↗
PubMed1993

The relative toxicity of disease-modifying antirheumatic drugs.

OBJECTIVE: To compare the toxicities of commonly employed disease-modifying antirheumatic drugs (DMARDs) in rheumatoid arthritis (RA). METHODS: Toxicity Index scores, computed from symptoms, laboratory abnormalities, and hospitalizations attributable to DMARD therapy, were assessed in 2,747 patients with RA receiving 3,053 courses of 6 DMARDs and 1,309 courses of prednisone over 7,278 patient-years. Results were adjusted for severity of illness and other covariates. RESULTS: Least toxic was hydroxychloroquine (mean +/- SEM score 1.38 +/- 0.15), followed by intramuscular gold (2.27 +/- 0.17) and the closely grouped D-penicillamine (3.38 +/- 0.36), methotrexate (3.82 +/- 0.35), and azathioprine (3.92 +/- 0.39). Auranofin (5.25 +/- 0.32) was most toxic, but this toxicity resulted from a high frequency of minor complications. Hospitalizations because of auranofin or hydroxychloroquine therapy were not noted. Prednisone (3.83 +/- 0.39) was of comparable toxicity, although it is likely that not all events of prednisone toxicity were captured. For reference, the toxicity of methotrexate and azathioprine was similar to that of the most toxic nonsteroidal antiinflammatory drugs (NSAIDs) (indomethacin 3.99, tolmetin sodium 3.96, and meclofenamate 3.86). Hydroxychloroquine showed less toxicity than the most commonly used prescription NSAIDs. CONCLUSION: There are substantial differences in toxicity among DMARDs and less important differences in toxicity between specific DMARDs and specific NSAIDs.

Anti-Inflammatory Agents↗
PubMed1993

A Canadian study of the total medical costs for patients with systemic lupus erythematosus and the predictors of costs.

OBJECTIVE: We conducted a cost identification analysis on 164 consecutive patients with systemic lupus erythematosus (SLE) who entered the Montreal General Hospital Lupus Registry between January 1977 and January 1990, compared their costs to the population of Quebec, and determined the predictors of cost. METHODS: In January 1990 and 1991, participants completed questionnaires on health services utilization and on employment history over the preceding 6 months, as well as on functional, psychological, and social well-being. The societal burden of SLE was determined in terms of direct costs (all resources consumed in patient care) and indirect costs (wages lost due to lack of work force participation because of morbidity). RESULTS: The mean total annual cost for 1989, as assessed in January 1990 and expressed in 1990 Canadian dollars, was $13,094. Although only 44% of the patients were fully employed, indirect costs were responsible for 54% of this total ($7,071). Ambulatory costs, primarily diagnostic procedures, medications, and visits to health care professionals, comprised 55% of direct costs ($3,331). The results of the 1990 cost determination were similar. On average, hospitalizations among SLE patients were 4 times more frequent than among the general population of Quebec (matched for age and sex), and the number of ambulatory visits to physicians was double that for the average resident of Quebec. Higher 1989 values of creatinine and a poorer level of physical functioning were the best predictors of higher 1990 direct costs (R2 = 0.29). A poorer SLE well-being score, a combination of education and employment status, and a weaker level of social support were the best predictors of higher indirect costs (R2 = 0.29). CONCLUSION: The direct and indirect costs for patients with SLE are substantial, and their respective predictors are distinct. Direct costs arise from organic complications which induce functional disability. Predictors of indirect costs are potentially amenable to psychological or social interventions and may be more easily modified than the determinants of direct costs, thereby improving patient outcome while simultaneously reducing disease costs.

Adolescent↗
PubMed1993

Estimating lumbar bone mineral density from routine radiographs of the lumbar spine.

To evaluate the information content of lateral lumbar films with respect to bone mineral content, we compared reading criteria with values obtained by quantitative computed tomography (CT) of L1 at baseline and after 5 years. The highest correlations with mineral content were found for the criteria "overall assessment of the vertebra", "vertebral bone density versus soft tissue", and "amount of trabeculations". These three reading criteria yielded higher correlations with CT scores in subjects with lower body mass index. Changes in mineral content over the 5-year period could not be read adequately, the average difference representing only a loss of about 10% in the study subjects. We conclude that a rough estimate of bone density can be obtained from lateral radiographs which, in the presence of eventual risk factors for osteoporosis, may serve as an additional indication to timely bone densitometry with methods which allow precise short-term follow-up measurements.

Aged↗
PubMed1993

Tobit, fixed effects, and cohort analyses of the relationship between severity and duration of rheumatoid arthritis.

Three methodological problems are commonly faced by researchers investigating relationships between severity and duration of illness among patients with rheumatoid arthritis (RA). (1) Linear regression techniques yield biased estimates when measures of severity are continuous but range between and include limiting values such as 0 and 3. (2) Data from the same patient over time are typically pooled together with data from different patients at the same time and over time. Models are then used that do not account for the statistical problems that can result from pooling. (3) Persons with varying years of duration of disease are typically combined and analyzed without any special attention to cohort effects. Changes in severity over time for cohorts of patients with fewer than 10 years of duration may be different from changes in severity of patients with more than 20 years of duration from the onset of the disease. In this study, severity is measured by the 0-3 disability scale in the Stanford Health Assessment Questionnaire (HAQ). Duration is measured by self-report of the onset of symptoms by subjects. Popular techniques are borrowed from econometrics--Tobit, Fixed Effects, and dummy variables for Cohort Models--that were developed to address three analogous problems in economic data. The three economic techniques are applied separately and together using data collected by Arthritis, Rheumatism, and Aging Medical Information System (ARAMIS) on 330 RA patients in 1981 who were followed until 1989. Although the Tobit technique does not appear to be especially useful with these data, Fixed Effects and Cohort Models do appear to be useful.(ABSTRACT TRUNCATED AT 250 WORDS)

Activities of Daily Living↗
PubMed1993

The relative toxicity of alternative therapies for rheumatoid arthritis: implications for the therapeutic progression.

The traditional pyramid for the therapeutic progression in rheumatoid arthritis (RA) is based on assumptions that RA is a mild disease, that nonsteroidal antiinflammatory drugs (NSAIDs) have low toxicity, and that disease-modifying antirheumatic drugs (DMARDs) are extremely toxic. This article reviews data from ARAMIS (Arthritis, Rheumatism, and Aging Medical Information System), casting strong doubt on these assumptions. NSAIDs result in 1.3% excess gastrointestinal hospitalizations per year. Mortality rates in RA are far above those expected from age- and sex-matched populations. Individual NSAIDs show widely different overall quantitative toxicity indices, as do individual DMARDs. However, the ranges of toxicity of the two classes of drugs show nearly complete overlap. It is suggested that the new therapeutic progression in RA should emphasize initial use of DMARDs, beginning with the least toxic.

Anti-Inflammatory Agents↗
PubMed1993

Seasonal variation in the onset of Wegener's granulomatosis, polyarteritis nodosa and giant cell arteritis.

OBJECTIVE: The hypothesis of a seasonal pattern in the onset of symptoms for some vasculitides has been raised in previous small studies. METHODS: Using the data collected by the American College of Rheumatology (ACR) Subcommittee on Classification of Vasculitis, we specifically tested for a higher proportion of onset of symptoms in winter, lower in summer, and intermediate for the other seasons for polyarteritis nodosa (PAN) and Wegener's granulomatosis. We also tested for a higher proportion of onset of symptoms in the spring-summer months for giant cell arteritis (GCA). RESULTS AND CONCLUSIONS: The results of our study support the hypothesis of a seasonal trend for the onset of symptoms of Wegener's granulomatosis (p = 0.04) as described previously. No seasonal pattern was found for the other vasculitides studied (PAN and GCA).

Giant Cell Arteritis↗
PubMed1993

Unilateral ptosis as an initial manifestation of D-penicillamine induced myasthenia gravis.

We describe 2 patients presenting with isolated unilateral ptosis without other signs of cranial or peripheral nerve involvement or sympathetic denervation. Both patients (one case of progressive systemic sclerosis and one of rheumatoid arthritis) were currently taking D-penicillamine. In these cases, the ptosis was reversed a few minutes after a Tensilon test, hallmark of myasthenia gravis. Antibodies to acetylcholine receptors were present. Myasthenia gravis should be suspected with ptosis without other cranial nerve involvement or miosis, even if the ptosis is unilateral. Thus, unilateral ptosis can be the first manifestation of a toxic side reaction to D-penicillamine.

Adult↗
PubMed1993

Fractures in rheumatoid arthritis: an evaluation of associated risk factors.

OBJECTIVE: Our purpose was to identify factors indicative of a high fracture risk during the disease course of rheumatoid arthritis (RA). METHODS: In 1110 patients (879 women and 231 men) with RA from five Arthritis, Rheumatism and Aging Medical Information System centers, information from history, clinical and laboratory examination, outcome assessment, and therapy was evaluated for association with the 226 first fractures having occurred during the years from 1975 to 1988. RESULTS: The mean age of the patients was 54 years, the mean time of observation was 8 years. Multivariate analyses identified the following factors to be associated with fracturing: years taking prednisone, previous diagnosis of osteoporosis, disability, age, lack of physical activity, female sex, disease duration, impaired grip strength, and low body mass. CONCLUSION: We conclude that patients with RA at greatest risk for fracturing are easily identified by using a few clinical variables. These findings support encouragement of active lifestyle habits and avoidance of longterm administration of corticosteroids in patients with RA.

Aging↗
PubMed1993

The relationship between spinal and peripheral osteoarthritis and bone density measurements.

OBJECTIVE: To determine the influence of osteoarthritis (OA) on bone density measurements and whether OA at one site is associated with OA at other sites. METHODS: Nonrandomized, cross sectional observational study; secondary analysis of a general population database. Sixty-four subjects derived from a longitudinal study of long distance runners and community controls had a complete peripheral radiographic evaluation for osteoarthritic changes in hands, knees, and lumbar spine. Forty-four of these were studied in 1984 with quantitative computed tomography (QCT) of L1, and 54 were studied in 1988 with 153-Gd dual photon absorptiometry (DPA) in the spine and total body. Thirty-four subjects had all measurements done. RESULTS: Total body and lumbar spine DPA were positively correlated with radiological scores of OA in the spine and knees, with coefficients ranging between 0.467 to 0.530 (p < 0.001 in all cases). This correlation was principally associated with spinal spurs and knee sclerosis. Results of stepwise multiple linear regression modeling for QCT included age, spine sclerosis, knee sclerosis and knee spurs as the main predictors of bone mineral density (BMD). For DPA measurements, spine spur score was a useful regressor for all the models. Altogether, the percentage of variance accounted for by individual radiological OA variables was 27.4% for lumbar QCT, 27.3% for lumbar BMD, 7.3% for total spine BMD, and 45.2% for total body BMD. OA scores at different sites were not correlated, although repeated assessment at the same site showed very close correlation. CONCLUSIONS: All methods used to determine BMD showed a highly significant positive correlation between lumbar and knee radiological OA and bone mineral content both in the spine and the total body. Thus, our results support the hypothesis that OA is negatively correlated with osteopenia. OA, as seen in this population, was not a generalized condition, but rather, was site specific.

Aged↗
PubMed1993

Detecting treatment effects in patients with rheumatoid arthritis: the advantage of longitudinal data.

Assessment of therapy in patients with rheumatoid arthritis is important but difficult. We examined 4 different methods of analyzing pretreatment data and assessed the difference that each made in detecting a positive effect of intramuscular gold on the patient's overall disability. The methods were (1) calculating the arithmetic mean of prior data points, (2) taking the last data point pretreatment, (3) fitting a straight line to pretreatment points and (4) fitting the pretreatment points with a quadratic equation. After comparison with matched controls (not taking remittive agents) the most significant difference was found by fitting a straight line to pretreatment data. This technique demonstrated about one-third more of intramuscular gold's effectiveness than the usual technique of using the last data point pretreatment. We conclude that statistical power is improved by obtaining and analyzing longitudinal pretreatment data appropriately.

Arthritis, Rheumatoid↗
PubMed1993

The risk of osteoarthritis with running and aging: a 5-year longitudinal study.

Our purpose was to determine the 5-year longitudinal effects of running and aging on the development of radiographic and clinical osteoarthritis (OA) of the knees, hands and lumbar spine. Thirty-five running subjects and 38 controls, with a mean age of 63 years, were matched for age (+/- 2 years), years of education, and occupation; 33 matched pairs were constructed. All subjects underwent rheumatologic examination, completed questionnaires, and had radiographs taken of the hands, lateral lumbar spine, and knees in 1984 and in 1989. Five year radiographic results for both the runner and control groups showed OA progression for the knees, hands, and lumbar spine. In 1989, 10 (13%) of the 73 subjects fit American College of Rheumatology (ACR) criteria for clinical OA of the hand, and 9 subjects (12%) fit ACR criteria for OA of the knee. In summary, running did not accelerate the development of radiographic or clinical OA of the knees, but with aging, 13% of all subjects developed OA of the hands and 12% of all subjects developed OA of the knees.

Aged↗