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David T Felson

Publications and source records attributed to David T Felson.

70 records · Page 4Linked to original sources
PubMed2002

Bone mass and the risk of prostate cancer: the Framingham Study.

PURPOSE: To examine the relation of bone mass-a potential biologic marker for cumulative exposure to androgens, insulin-like growth factors, and calcium intake-to subsequent development of prostate cancer. METHODS: We used radiogrammetry to measure the second metacarpal cortical area of 1012 white men with no history of prostate cancer who had undergone posteroanterior hand radiography between 1967 and 1970. Participants were followed until the end of 1999. All incident cases of prostate cancer were confirmed histologically. We examined bone mass in relation to the risk of prostate cancer using a Cox proportional hazards model. RESULTS: During follow-up, 100 men developed prostate cancer. Incidence rates per 1000 person-years were 3.8 among men in the lowest quartile of bone mass, 4.8 in the second quartile, 7.4 in the third quartile, and 6.5 in the highest quartile. Compared with men in the lowest quartile of bone mass, the multivariate-adjusted rate ratio was 1.3 (95% confidence interval [CI]: 0.7 to 2.5) for those in the second quartile, 1.9 (95% CI: 1.0 to 3.4) in the third quartile, and 1.6 (95% CI: 0.9 to 3.0) in the highest quartile (P for trend = 0.06). CONCLUSION: Men with high bone mass may be at an increased risk of prostate cancer. Although the biological mechanisms underlying this relation are not understood, cumulative exposure to high levels of androgen, insulin-like growth factor 1, or calcium intake may be involved.

Bone and Bones↗
PubMed2002

Truth survival.

Explore the source record for details and available documents.

Bias↗
PubMed2002

Prevalence of symptomatic hand osteoarthritis and its impact on functional status among the elderly: The Framingham Study.

Osteoarthritis is one of the most common joint disorders in the elderly, yet few studies have targeted symptomatic osteoarthritis, especially symptomatic hand osteoarthritis. The authors conducted a survey in 1992-1993 among an elderly population to estimate the prevalence of symptomatic hand osteoarthritis and to assess its impact on grip strength and functional activities. Framingham Study subjects received hand radiographs and answered queries on joint symptoms. Functional activities were assessed using an interviewer-administered questionnaire. Grip strength and observed functional performance were evaluated using standard procedures. A hand joint was defined as having symptomatic osteoarthritis if both symptoms and radiographic evidence of osteoarthritis were present. Of 1,041 subjects aged 71-100 years (36% men), the prevalence of symptomatic hand osteoarthritis was higher in women (26.2%) than in men (13.4%). Compared with those without symptomatic hand osteoarthritis, subjects with the disease had 10% reduced maximal grip strength, reported more difficulty writing, handling, or fingering small objects (odds ratio = 3.4), and showed more self-reported and observed difficulty carrying a 10-pound (4.5-kg) bundle (odds ratio = 1.7 and 1.6, respectively). In conclusion, in the context of a remarkable paucity of data on the epidemiology of symptomatic hand osteoarthritis, this study suggests that symptomatic hand osteoarthritis is a common disease among elders and frequently impairs hand function.

Activities of Daily Living↗
PubMed2002

Statistical presentation and analysis of ordered categorical outcome data in rheumatology journals.

OBJECTIVE: To assess the appropriateness of presentation of summary measures and analysis of ordered categorical (ordinal) data in three rheumatology journals in 1999, and to consider differences between basic and clinical science articles. METHODS: Six hundred forty-four full-length articles from the 1999 editions of 3 rheumatology journals were evaluated for inclusion of an ordinal outcome. Articles were classified as basic or clinical science, and the appropriateness of presentation and analysis of the ordinal outcome were assessed. Chi-square tests were used to evaluate difference in percentages. RESULTS: Ordinal outcomes were identified in 175 (27.2%) of 644 articles. Only 69 (39.4%) had appropriate data presentation, and 111 (63.4%) had appropriate data analysis. Appropriate presentation was seen less commonly in the basic science rather than the clinical science articles, but differences in the occurrence of appropriate analysis were not seen. CONCLUSION: Ordinal data are common in rheumatology articles, but presentation usually does not conform to recommended guidelines.

Data Collection↗
PubMed2002

High prevalence of lateral knee osteoarthritis in Beijing Chinese compared with Framingham Caucasian subjects.

OBJECTIVE: We recently reported that, despite their thinness, elderly subjects in Beijing, China had an equal prevalence (in men) or higher prevalence (in women) of both radiographic and symptomatic knee osteoarthritis (OA) compared with that in the Framingham, Massachusetts cohort of elderly subjects. Our objective was to evaluate whether Chinese subjects might have more medial disease than do Caucasians, given a report of varus alignment in the knee joints of Chinese elderly. METHODS: We compared the prevalence of medial and lateral radiographic knee OA and measured anatomic alignment in the knees of elderly subjects from the Beijing and Framingham cohorts. Both studies recruited a random sample of the population. The Beijing OA Study used the Framingham OA Study protocol for radiographs. Anteroposterior weight-bearing films were read for Kellgren and Lawrence (K/L) grade and joint space narrowing (JSN; 0-3 scale) in each compartment. Medial disease was defined when radiographs showed a K/L grade >or=2 and medial JSN >or=1, and lateral disease was assessed in a comparable manner. Using knee-specific analyses, we compared the prevalence of medial and lateral knee OA after adjusting for age, body mass index, and the correlation between the 2 knees. Restricting the analyses to knees with JSN >or=2 and comparing the proportion of OA knees with medial disease and lateral disease yielded similar results. We assessed alignment in knees from 100 persons without OA, measuring the angle subtended by the femoral and tibial anatomic axes. RESULTS: We studied 1,781 Chinese subjects ages 60-88 years, and 1,084 Framingham subjects ages 63-93 years. Whereas medial OA was less prevalent among the Beijing men, lateral OA was more than twice as prevalent among the Beijing men and women, compared with that in the Framingham elderly. For example, of all knees with radiographic OA, 28.5% of Beijing women's knees had lateral OA versus 11% of Framingham women's knees (P < 0.001), and among men, 32.3% of Beijing men's knees versus 8.8% of Framingham men's knees (P < 0.001) had lateral OA. Alignment was more valgus in the Beijing men than in the Framingham men (mean 4.5 degrees versus 2.7 degrees valgus, respectively; P < 0.001), but no differences in alignment were evident in the women. CONCLUSION: In this first attempt to compare the characteristics of OA in different racial groups, we conclude that, opposite to expectations, Chinese subjects have much more lateral OA than do Caucasian subjects in the Framingham cohort, a predilection possibly explained in the men by differences in anatomic alignment.

Aged↗
PubMed2002

Very low prevalence of hip osteoarthritis among Chinese elderly in Beijing, China, compared with whites in the United States: the Beijing osteoarthritis study.

OBJECTIVE: To compare the prevalence of osteoarthritis (OA) of the hip among elderly persons in China and the US. METHODS: We recruited a population-based sample of 1,506 persons (82% of those enumerated) ages > or = 60 years living in Beijing, China. Subjects answered questions about joint symptoms and underwent radiography of the pelvis. Radiographs of the Beijing subjects were intermingled with hip radiographs of white women ages > or = 65 years from the Study of Osteoporotic Fractures (SOF) and white men and women ages 60-74 years from the First National Health and Nutrition Examination Survey (NHANES-I) and were then interpreted. Radiographic hip OA was defined as the presence of 1 of the following 3 findings in either hip: minimum joint space of < or = 1.5 mm, definite osteophytes and joint space narrowing, or > or = 3 radiographic features of OA. Symptomatic hip OA was defined as both radiographic OA and hip pain. RESULTS: The crude prevalence of radiographic hip OA in Chinese ages 60-89 years was 0.9% in women and 1.1% in men; it did not increase with age. Chinese women had a lower age-standardized prevalence of radiographic hip OA compared with white women in the SOF (age-standardized prevalence ratio 0.07) and the NHANES-I (prevalence ratio 0.22). Chinese men had a lower prevalence of radiographic hip OA compared with white men of the same age in the NHANES-I (prevalence ratio 0.19). There were no cases of symptomatic hip OA in the Chinese men and only 1 case in the Chinese women; 35 cases were expected in both sexes. CONCLUSION: This is the first population-based study of hip OA in China to use standardized radiographic methods and definitions. We found that hip OA was 80-90% less frequent than in white persons in the US. Identification of the genetic and environmental factors that underlie these differences may help elucidate the etiology and prevention of hip OA.

Aged↗
PubMed2002

Secular changes in the quality of published randomized clinical trials in rheumatology.

OBJECTIVE: To assess the quality of published randomized clinical trials (RCTs) in rheumatology and to determine whether there has been improvement in quality between 2 time periods, 1987-1988 and 1997-1998. METHODS: Using MEDLINE and a hand search of selected rheumatology journals, we identified RCTs of adult rheumatic diseases published in English in 1987-1988 or 1997-1998. We examined trial quality with an expanded version of the Jadad scale, which assesses the adequacy of reported random sequence generation, allocation concealment, blinding, and analysis. All trials were read by 1 reviewer, with prior standardization using a random sample read by 2 reviewers. We also evaluated "high"- versus "low"-impact journals based on citation index. RESULTS: Two hundred forty RCTs (1987-1988 119 RCTs, 1997-1998 121 RCTs) were assessed. Results showed improvement in the quality of the trials, but the rates of reported random sequence generation, allocation concealment, power, and intent-to-treat analyses were persistently low. Low rates of reports of random sequence generation, allocation concealment, and intent-to-treat analyses were present even in the high-impact journals. CONCLUSION: There has been improvement in the quality of reporting of RCTs in rheumatology between 1987-1988 and 1997-1998. However, methodologic problems such as lack of allocation concealment, inadequate random sequence generation, lack of reporting of power, and lack of intent-to-treat analyses remain common. Many of these problems are established sources of bias in RCTs and are easily rectifiable.

Humans↗
PubMed2002

Discrepancy between published report and actual conduct of randomized clinical trials.

Randomized clinical trial (RCT) publications with inappropriate random-sequence generation, lack of allocation concealment, or imperfect blinding yield inflated estimates of effect compared to those in which adequate methods are described. RCTs that do not state methods used yield similar effect estimates, suggesting that inadequate methods were used. We compared RCT publications with investigator reports of actual practice for 40 rheumatology RCTs published in 1997/1998. In RCTs in which these methods were not described in the trial reports and would thus have been characterized as "inadequate," investigators reported using methods of random-sequence generation and allocation concealment that would be considered adequate in 77.4 and 78.1% of RCTs, respectively. This suggests that, in contrast to previous reports, inadequate random-sequence generation and allocation concealment, per se, may not be a major problem in RCTs. Characterizing RCTs as "good" or "poor" quality based on the published report is likely to be inappropriate.

Bias↗
PubMed2002

Effectiveness of a lateral-wedge insole on knee varus torque in patients with knee osteoarthritis.

OBJECTIVES: To test whether a lateral-wedged insole, inclined at 5 degrees or 10 degrees, significantly reduces knee varus torque during walking in patients with knee osteoarthritis compared with both using no insole and with wearing nonwedged control insoles of the same material and average thickness. DESIGN: Patients with medial knee osteoarthritis were studied while they walked wearing their comfortable shoes (1) without an insole; (2) with a 5 degrees lateral wedge compared with a nonwedged, 3.175-mm (1/8-in) even-thickness control insole; and (3) with a 10 degrees lateral wedge compared with a nonwedged 6.35-mm ((1/4)-in) even-thickness control insole. SETTING: A gait laboratory with 3-dimensional motion analysis and force platform equipment. PARTICIPANTS: Fifteen patients with clinical and radiographic osteoarthritis of the medial compartment of 1 knee. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Peak external knee varus torques during the stance period of gait. Data regarding lower-extremity joint torques and motions were collected, and knee joint torques using the different insoles and wedges were compared by analysis of variance. RESULTS: Although responses varied among individuals, as a group, both the 5 degrees and 10 degrees lateral-wedge insoles significantly reduced the knee varus torque during walking compared with walking with no insole and walking with nonwedged 3.175-mm and 6.35-mm control insoles. Compared with no insole, the 5 degrees wedge reduced the peak knee varus torque values by about 6% and the 10 degrees wedge reduced the peaks by about 8%. Although there were no significant differences in speed of walking between the conditions, the 10 degrees wedge and 6.35-mm control insoles were associated with varying degrees of discomfort. CONCLUSION: Both wedge insoles are effective in reducing the varus torque during walking beyond what theoretically could be explained by a reduced walking speed or cushioning effect from the insole. These data imply that wedged insoles are biomechanically effective and should reduce loading of the medial compartment in persons with medial knee osteoarthritis. Although the effect of the 5 degrees wedge was smaller, it may be more comfortable than the 10 degrees wedge to wear inside one's own shoes.

Aged↗
PubMed2002

The comparative efficacy of drug therapies used for the management of corticosteroid-induced osteoporosis: a meta-regression.

We determined the comparative efficacy of vitamin D, calcitonin, fluoride, and bisphosphonates for the management of corticosteroid-induced osteoporosis using meta-regression models. A systematic search for trials was conducted using MEDLINE, bibliographic references, abstracts from national meetings, and contact with pharmaceutical companies and content experts. We included all randomized controlled trials, lasting at least 6 months, of adult patients on oral corticosteroids that evaluated treatment comparisons between vitamin D, calcitonin, bisphosphonates, or fluoride either with no therapy/calcium or with each other and that reported extractable results. The outcome measure of interest was change in lumbar spine bone mineral density (BMD). We identified 45 eligible trials, which provided 49 eligible treatment comparisons (some trials had three arms or more). Our results indicated that bisphosphonates were the most effective class (effect size 1.03; 95% CI: 0.85, 1.17); results were similar even when newer generations of nitrogen-containing bisphosphonates were excluded from analysis. We found the efficacy of bisphosphonates was enhanced further when used in combination with vitamin D (effect size, 1.31; 95% CI: 1.07, 1.50). Vitamin D and calcitonin were more effective than no therapy/calcium (effect size, 0.46; 95% CI: 0.27, 0.62; and effect size, 0.51; 95% CI: 0.33, 0.67, respectively) and were of similar efficacy, but both were significantly less effective than bisphosphonates. Fluoride appeared effective, but there were too few studies (n = 5) to draw robust conclusions regarding its efficacy compared with the other three therapies. In summary, bisphosphonates are the most effective of evaluated agents for managing corticosteroid-induced osteoporosis. The efficacy of bisphosphonates is enhanced further with concomitant use of vitamin D.

Adrenal Cortex Hormones↗
PubMed2002

Effect of birth cohort on risk of hip fracture: age-specific incidence rates in the Framingham Study.

OBJECTIVES: This study examined the effect of birth cohort on incidence rates of hip fracture among women and men in the Framingham Study. METHODS: Age-specific incidence rates of first hip fracture were presented according to tertile of year of birth for 5209 participants of the Framingham Study, a population-based cohort followed since 1948. Sex-specific incidence rate ratios were calculated by Cox regression to assess the relation between birth cohort and hip fracture incidence. RESULTS: An increasing trend in hip fracture incidence rates was observed with year of birth for women (trend, P =.05) and men (trend, P =.03). Relative to those born from 1887 to 1900 (incidence rate ratio [IRR] = 1.0), age-specific incidence rates were greatest in the most recent birth cohort, born from 1911 to 1921 (IRR = 1.4 for women, IRR = 2.0 for men), and intermediate in those born from 1901 to 1910 (IRR = 1.2 for women, IRR = 1.5 for men). CONCLUSIONS: Results suggest risk of hip fracture is increasing for successive birth cohorts. Projections that fail to account for the increase in rates associated with birth cohort underestimate the future public health impact of hip fracture in the United States.

Adult↗
PubMed2002

Comparison of the prevalence of radiographic osteoarthritis of the knee and hand between Japan and the United States.

OBJECTIVE: There is no direct international comparison of the prevalence of osteoarthritis (OA) between Japanese and Caucasians. We compared the prevalence of radiographic knee and hand OA between women in Hizen-Oshima, Japan, and in Framingham, Massachusetts, USA. METHODS: A population based cross sectional study among 358 women in Japan and 815 women in the USA aged 63 years or older for knee joints, and 157 women in Japan and 655 women in the USA aged 71 years or older for hands. Radiographs were obtained of knees and hands, and were graded according to the Kellgren-Lawrence (K-L) criteria. Definite OA was defined as K-L grade 2 or higher, present in at least one joint of a given group. A person was defined as having OA or not in a given joint group, and we used logistic regression with the US group as referent to determine the prevalence odds ratio of OA among Japanese. RESULTS: The age adjusted prevalence of knee OA in Japanese women was higher than in Caucasians (OR 1.96, 95% CI 1.50-2.56), while the prevalence of hand OA other than distal interphalangeal joint in Japanese was lower than in Caucasians (OR for proximal interphalangeal joint 0.66, 95% CI 0.46-0.93; OR for metacarpophalangeal joint 0.62, 95% CI 0.42-0.90), especially base of thumb OA (OR 0.15, 95% CI 0.11-0.22). CONCLUSION: These findings suggest site-specific differences in the prevalence of OA that may be attributed to genetic and/or environmental factors.

Age Distribution↗
PubMed2002

Relative costs and effectiveness of specialist and general internist ambulatory care for patients with 2 chronic musculoskeletal conditions.

OBJECTIVE: To evaluate costs and effectiveness of ambulatory care provided by specialists, nonspecialists (general internists), and both specialists and nonspecialists (co-care) to patients with knee osteoarthritis (OA) and/or chronic low back pain (LBP). METHODS: We studied Veterans Health Administration (VHA) outpatients from the Veterans Health Study with LBP and/or OA followed for at least 6 months between August 1993 and December 1995, who completed the Medical Outcomes Study Short Form 36-item (SF-36) functional status questionnaires at both baseline and followup. We obtained costs of VHA outpatient utilization and medications for these patients during the followup period. We compared costs and effectiveness of the ambulatory care provided by specialists, nonspecialists, and co-care. We also compared specialty care with nonspecialty care using an incremental cost effectiveness ratio (ICER) of annualized cost difference divided by annualized SF-36 based Physical Component Summary (PCS) improvement difference. ICER stability was assessed using bootstrap sampling. RESULTS: Among 398 patients, followed an average of 14 months, 155 received only nonspecialty care, 49 specialty-only care, and 192 co-care. After regression analysis, adjusted for age, disease characteristics, and baseline health status, PCS improvements per year were 1.66 (SD 8.22) for nonspecialty care, 3.48 (SD 7.91) for specialty care, and 0.65 (SD 8.08) for co-care; while costs of care per year were $1099 (SD $1681), $1376 (SD $1503), and $2517 (SD $1644), respectively (all data US dollars). A standardized ICER of $152 per PCS unit indicated specialty care to be cost effective compared with nonspecialty care. CONCLUSION: Specialist-only ambulatory care for OA or LBP was associated with improvement in functional status at slightly higher costs compared with nonspecialty care. Co-care, however, was substantially more costly and was associated with little improvement in functional status.

Adult↗