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J J Anderson

Publications and source records attributed to J J Anderson.

At least 109 records · Page 6Linked to original sources
PubMed1993

The American College of Rheumatology preliminary core set of disease activity measures for rheumatoid arthritis clinical trials. The Committee on Outcome Measures in Rheumatoid Arthritis Clinical Trials.

OBJECTIVE: To develop a set of disease activity measures for use in rheumatoid arthritis (RA) clinical trials, as well as to recommend specific methods for assessing each outcome measure. This is not intended to be a restrictive list, but rather, a core set of measures that should be included in all trials. METHODS: We evaluated disease activity measures commonly used in RA trials, to determine which measures best met each of 5 types of validity: construct, face, content, criterion, and discriminant. The evaluation consisted of an initial structured review of the literature on the validity of measures, with an analysis of data obtained from clinical trials to fill in gaps in this literature. A committee of experts in clinical trials, health services research, and biostatistics reviewed the validity data. A nominal group process method was used to reach consensus on a core set of disease activity measures. This set was then reviewed and finalized at an international conference on outcome measures for RA clinical trials. The committee also selected specific ways to assess each outcome. RESULTS: The core set of disease activity measures consists of a tender joint count, swollen joint count, patient's assessment of pain, patient's and physician's global assessments of disease activity, patient's assessment of physical function, and laboratory evaluation of 1 acute-phase reactant. Together, these measures sample the broad range of improvement in RA (have content validity), and all are at least moderately sensitive to change (have discriminant validity). Many of them predict other important long-term outcomes in RA, including physical disability, radiographic damage, and death. Other disease activity measures frequently used in clinical trials were not chosen for any one of several reasons, including insensitivity to change or duplication of information provided by one of the core measures (e.g., tender joint score and tender joint count). The committee also proposes specific ways of measuring each outcome. CONCLUSION: We propose a core set of outcome measures for RA clinical trials. We hope this will decrease the number of outcomes assessed and standardize outcomes assessments. Further, we hope that these measures will be found useful in long-term studies.

Arthritis, Rheumatoid↗
PubMed1993

Bone mineral density and knee osteoarthritis in elderly men and women. The Framingham Study.

OBJECTIVE: To examine the possible inverse relationship between osteoporosis and osteoarthritis (OA) by evaluating the association between bone mineral density (BMD) and knee OA in the Framingham Study cohort. METHODS: Of the 1,154 Framingham Study cohort subjects in whom BMD measurements were obtained at biennial examination 20, 932 (81%) had had knee OA assessed during the Framingham Knee OA Study 4 years earlier. BMD of the proximal femur and radius was measured by densitometry. Knee OA was assessed from a weight-bearing anteroposterior radiography and graded on a scale of 0 (no OA) to 4 (severe OA). Osteophytes and joint space narrowing were also evaluated separately. Linear regression was used to test the association of BMD with knee OA, with osteophytes, and with joint space narrowing, after adjustment for age, body mass index, and mean number of cigarettes smoked per day. RESULTS: The subjects included 572 women and 360 men with an age range of 63-91 years (mean 71 years). Of these, 351 had no OA, 269 had grade 1 OA, 170 had grade 2 OA, 93 had grade 3 OA, and 49 had grade 4 OA. Mean femoral BMD at the 3 proximal femur sites was 5-9% higher in men and women with either grade 1, grade 2, or grade 3 knee OA, compared with those with no knee OA (P < 0.0001). Mean femoral BMD in those with grade 4 OA was not higher than in those with no OA. Radius BMD was not associated with knee OA in subjects of either sex. Women with osteophytes had higher BMD compared with women with no osteophytes. Mean BMD did not differ across levels of joint space narrowing. CONCLUSION: We conclude that, among women, femoral BMD is higher in those with osteophytosis of the knee, and BMD is not necessarily associated with joint space narrowing.

Aged↗
PubMed1993

Effects of weight and body mass index on bone mineral density in men and women: the Framingham study.

We evaluated the association of weight and bone mass in elderly male and female subjects of the Framingham osteoporosis study, a subset of the Framingham study cohort. By examining the differences in the correlations of weight with bone mass among men and women in weight-bearing and non-weight-bearing sites and weight change since early adulthood, we attempted to understand different ways in which weight or body mass index affects bone mass. During biennial examination 20 of the Framingham cohort (1988-1989), 693 women and 439 men (mean age 76 years) had proximal femur bone mineral density assessed by dualphoton absorptiometry (DPA) and radius bone mass assessed by single-photon absorptiometry. The majority of these subjects also had spine measurements by DPA. Subjects had been weighed repeatedly over 40 years. After adjusting for other factors affecting bone density, we found that both recent weight and body mass index explained a substantial proportion of the variance in bone mineral density for all sites in women (8.9-19.8% of total variance, all p < 0.01) and for only weight-bearing sites (femur and spine) in men (2.8-6.9% of total variance, all p < 0.01). For bone mineral density at the proximal radius, weight and body mass index accounted for < 1% of variance in men (p NS). Weight change since biennial examination 1 (1948-1951) was the strongest explanatory factor for bone mineral density among women at all sites, but weight change did not affect radius bone mineral density in men. The effect of weight and of weight change on bone mineral density was in general much less in men than in women. Our results suggest that the strong effect of weight on bone mineral density is due to load on weight-bearing bones sexes. The sex difference is unexplained but may be due to adipose tissue production of estrogen in women after menopause.

Absorptiometry, Photon↗
PubMed1993

N-methyl-D-aspartate receptor blockade differentially modifies regional cerebral metabolic responses to D1 and D2 dopamine agonists in rats with a unilateral 6-hydroxydopamine lesion.

Dopamine and the excitatory amino acids play important roles in the control of motor behavior by the basal ganglia; elucidating the manner in which these transmitter systems interact may provide new therapeutic approaches to the treatment of movement disorders such as Parkinson's disease. The 2-deoxyglucose autoradiographic technique was used to examine the effect of N-methyl-D-aspartate receptor blockade on regional cerebral metabolic responses to D1 and D2 dopamine receptor stimulation in rats with a unilateral 6-hydroxydopamine lesion of the nigrostriatal pathway. The D1 agonist SKF 38393 (5 mg/kg, i.v.) increased glucose utilization markedly in entopeduncular nucleus and substantia nigra pars reticulata ipsilateral to the lesion, while the D2 agonist quinpirole (1 mg/kg, i.v.) had no effect in these striatal output regions. SKF 38393 and quinpirole reduced 2-deoxyglucose uptake to a similar extent in the lateral habenula, a region which receives afferent input from entopeduncular nucleus; quinpirole also decreased glucose utilization bilaterally in nucleus accumbens. Pretreatment with the noncompetitive N-methyl-D-aspartate receptor antagonist MK-801 (0.1 mg/kg, i.v.), which had little effect on cerebral metabolism by itself, reduced the effect of SKF 38393 in entopeduncular nucleus and substantia nigra pars reticulata and prevented the effect of quinpirole in nucleus accumbens. MK-801 did not alter the SKF 38393-induced reduction in glucose utilization in lateral habenula, but did reduce the effect of quinpirole in this structure. When these drugs were administered in the same manner to a separate group of lesioned animals, MK-801 did not affect rotational behavior elicited by SKF 38393, but completely eliminated contralateral rotation and actually caused some ipsilateral rotation in response to quinpirole. These findings indicate that D1 and D2 receptor-associated brain mechanisms are differentially influenced by N-methyl-D-aspartate receptor stimulation. D2-mediated behavioral and cerebral metabolic responses appear to require concurrent N-methyl-D-aspartate receptor stimulation. On the other hand, the preservation of D1-mediated rotational behavior and reduced lateral habenula glucose metabolism in the presence of MK-801 despite attenuation of the effects of the D1 agonist in entopeduncular nucleus and substantia nigra pars reticulata suggests that D1 receptor-regulated neuronal pathways exhibit varying degrees of sensitivity to N-methyl-D-aspartate receptor blockade.

2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-ben↗
PubMed1993

Contributions of dietary calcium and physical activity to primary prevention of osteoporosis in females.

In the United States and many Western nations, increasing prevalence of osteoporotic fracture is contributing to the health care system burden, and costs and needs for medical services are predicted to increase significantly by the beginning of the 21st century. Recent reports investigating developmental changes in skeletal mass of adolescent girls and young women under different experimental or ecological conditions support the contention that modification of environmental factors, especially dietary calcium and physical activity, can favorably modulate bone mass and bone density compared to controls. The peripubertal period, starting as early as 10 years of age, seems to be most responsive to modification of environmental/lifestyle factors, whereas potential gains of bone mass during late adolescence and early adulthood, although smaller, may be more readily achieved through improved dietary calcium intakes and regular exercise programs. Scientific evidence in support of these beneficial effects on bone is presented as part of the rationale for prevention of osteoporotic fractures. Also discussed is the need for a national policy to prevent osteoporosis through primary prevention strategies focused at young girls prior to puberty. The goal would be for every prepubertal girl, over the next decade, to achieve peak bone mass (and density) of the spine, hips and other bones by age 20, i.e., early adulthood. A second target group for national policy should be women in their 20s. Attainment of the goal to gain 3-5% additional bone mass during this decade would prolong the time before the fracture threshold range (low bone mass) is reached in the postmenopausal decades.

Adolescent↗
PubMed1993

Intakes of calcium, phosphorus, and protein, and physical-activity level are related to radial bone mass in young adult women.

A cross-sectional study of 38 24-28-y-old Caucasian women was undertaken to identify associations between dietary factors, physical activity (PA), and radial bone measurements during the third decade. Measurements included radial bone mineral content (BMC) and bone density (BD), nutrient intakes, and PA patterns. PA and calcium intake were positively associated by multiple linear-regression analysis whereas protein and phosphorus were negatively associated with radial bone measurements (P < 0.05). Lean body mass was positively associated with mid BMC only (P = 0.0203). No significant effect of age on BD or BMC was observed. We conclude that in this sample of 24-28-y-old women BD and BMC did not differ by age, and behaviors that had a positive impact on radial bone measurements included at least moderate PA and adequate dietary calcium intake, whereas adverse dietary practices for BD included intakes of protein and phosphorus greater than recommended amounts.

Adult↗
PubMed1993

No evidence for altered muscle mitochondrial function in Parkinson's disease.

Recent reports indicate that reductions in mitochondrial respiratory chain function occur in substantia nigra, platelets, and muscle from patients with Parkinson's disease. To confirm and further characterise the presence of a generally distributed mitochondrial defect, mitochondrial metabolism was evaluated in muscle obtained from subjects with Parkinson's disease and from normal controls. Oxygen consumption rates in muscle mitochondria represented by complex I, complexes II-III, or complex IV did not differ between the two groups. Likewise, activities of rotenone sensitive NADH cytochrome c reductase, succinate cytochrome c reductase, or cytochrome oxidase in muscle mitochondria were not significantly different between Parkinsonian and control subjects. These findings fail to provide support for a generalised defect in mitochondrial function in Parkinson's disease but do not exclude an abnormality in respiratory function confined to the substantia nigra.

Adult↗
PubMed1993

Hypertension increases the risk of renal deterioration in systemic lupus erythematosus.

OBJECTIVE: To assess the effect of hypertension on the development of renal functional deterioration, end stage renal disease and death in patients with systemic lupus erythematosus (SLE). METHODS: Person-years analysis using regression techniques to adjust for other baseline risk factors for adverse renal and patient survival outcomes. RESULTS: Six hundred eighty-five patients with SLE were followed for a total of 4,137 person-years. The risk of renal deterioration (doubling of serum creatinine) and endstage renal disease (ESRD) both increased with increasing baseline mean arterial pressure (MAP) (both p > 0.05). Even after adjustment for age, sex, baseline serum creatinine, C3, erythrocyte sedimentation rate, hematocrit, anti-DNA antibodies, and proteinuria, those in the highest quartile of MAP had 2.3 times the odds of renal deterioration at 12 months and 4.6 times the odds of ESRD compared to those in the lowest quartile of MAP (both p < 0.01 comparing highest to lowest quartile of MAP). Also, hypertension increased the risk of mortality, especially between one and 2 years after blood pressure determination. The effect of hypertension was also independent of corticosteroid dose. CONCLUSION: In patients with SLE, hypertension is a potent independent risk factor for adverse renal outcomes, and it also increases the risk of death.

Adult↗
PubMed1993

Sensitivity to change of rheumatoid arthritis clinical trial outcome measures.

OBJECTIVES: To present the properties of an efficiency measure that may be used to make statistical comparisons of sensitivities of trial outcome measures. To use this measure to examine the relative sensitivities of several common rheumatoid arthritis (RA) trial outcome measures in 2 different trial settings. METHODS: Efficiency is expressed as the mean change divided by the standard deviation of change. Variability and correlations of efficiencies for typical RA trial outcomes are described. RESULTS: From among a variety of joint assessments and other clinical measures, pain and global measures, and health status and laboratory measures, the joint tenderness and pain measures were the most sensitive, both in a trial of nonsteroidal antiinflammatory drugs (NSAID) and in a set of second-line drug trials. Measures with rather different sensitivities in the 2 types of trials were erythrocyte sedimentation rate (low sensitivity in the NSAID trial) and physician and patient global measures (higher sensitivity in the NSAID trial). CONCLUSION: The use of statistical information on efficiency estimates allows for a variety of comparisons of measures and may inform the selection of outcome measures for clinical trials.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1993

Habitual physical activity is not associated with knee osteoarthritis: the Framingham Study.

We evaluated the potential risk factor by examining levels of habitual physical activity during middle age, and knee osteoarthritis (OA) in later years in the Framingham Cohort. Weight-bearing knee radiographs were obtained during the 18th biennial examination (1983-85), when the 1,415 subjects had a mean age of 73 years. Cohort members had been asked at 1954-57 and 1971-73 about the number of hours spent daily at various levels of physical activity, ranging from sedentary to heavy activity. Physical capacity measures, such as forced expiratory volume in one second and resting pulse rate, were also examined for association with OA. In the cohort, 97/589 men and 154/826 women had OA. We found no association between habitual physical activity and knee OA after adjusting for age, body mass index, knee injury, smoking and education. In the highest quartile of habitual physical activity compared to the least active, the aOR for men was 1.34 (95% CI: 0.66, 2.74) and for women was 1.09 (95% CI: 0.63, 1.90). There was no increase in the risk of knee OA with increasing physical activity in either men or women. Physical capacity measures were also unassociated with OA. Of interest, men with high levels of habitual physical activity had significantly elevated rates of asymptomatic osteophytes, [aOR = 2.14, (95% CI: 1.01, 4.54)], suggesting that habitual physical activity may influence development of osteophytes but not of more severe or symptomatic knee OA. In sum, habitual physical activity does not increase the risk of knee OA for men or women.

Aged↗
PubMed1992

Differential effect of subthalamic nucleus ablation on dopamine D1 and D2 agonist-induced rotation in 6-hydroxydopamine-lesioned rats.

The effect of unilateral subthalamic nucleus ablation on rotation in response to dopamine D1 and D2 agonists was examined in rats with a unilateral 6-OHDA lesion of the nigrostriatal pathway. Four to five weeks following subthalamic nucleus lesion, D2 agonist-induced rotation was reduced in subthalamic nucleus-lesioned rats relative to sham controls, although no such reduction in D1 agonist-induced circling occurred. However, 1-2 weeks following subthalamic nucleus lesion marked reductions occurred in both D1 and D2 agonist-induced rotation in subthalamic nucleus lesioned rats compared to sham controls. These results suggest that the subthalamic nucleus contributes primarily to the expression of D2-mediated motor behaviors, although ablation of the subthalamic nucleus may induce certain time-dependent compensatory mechanisms in other basal ganglia structures which affect D1-mediated actions.

2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-ben↗
PubMed1992

Smoking eliminates the protective effect of oral estrogens on the risk for hip fracture among women.

OBJECTIVE: To determine if the association between smoking and osteoporotic fractures is related to the quantity of cigarettes smoked and to determine if smoking modifies the protection by estrogens. DESIGN: Cohort study. SETTING: A population-based cohort study, the Framingham Study. PARTICIPANTS: A total of 2873 women in the Framingham Study followed through examination 19 (1985-1987). MEASUREMENTS: All fractures of the proximal femur sustained by women in the Framingham Study from 1948 to 1987 were ascertained. At almost all examinations, available information on cigarette smoking was used to classify women as "ever smokers" compared with "never smokers," and, among "ever smokers," "current" compared with "former smokers." A similar classification for estrogen use was created. Information on potentially confounding variables was taken from each examination, including age, adiposity (weight/height2), alcohol consumption (ounces per week), and caffeine intake (coffee and tea). RESULTS: Overall, 207 hip fractures occurred among 34,700 woman-examinations of observation. In the entire cohort, current smoking did not appear to increase hip fracture risk (adjusted odds ratio [AOR], 1.22; 95% CI, 0.76 to 1.95; P greater than 0.2). Also overall, current estrogen use appeared to be protective (AOR, 0.38; CI, 0.12 to 1.21, P = 0.10). Among current smokers, however, estrogen use did not protect against fracture (AOR for current use, 1.26; CI, 0.29 to 5.45), whereas estrogen was protective in nonsmokers (AOR for current or past use, 0.37; CI, 0.19 to 0.75; P = 0.005). CONCLUSIONS: Overall, smoking does not appear to increase the risk for hip fracture in women. Although estrogen replacement protects nonsmokers from fracture, smoking may negate the protective skeletal effects of estrogen replacement therapy.

Administration, Oral↗
PubMed1992

Weight loss reduces the risk for symptomatic knee osteoarthritis in women. The Framingham Study.

OBJECTIVE: To evaluate the effect of weight loss in preventing symptomatic knee osteoarthritis in women. DESIGN: Cohort analytic study. SETTING: The Framingham Study, based on a sample of a defined population. PATIENTS: Women who participated in the Framingham Knee Osteoarthritis Study (1983 to 1985): Sixty-four out of 796 women studied had recent-onset symptomatic knee osteoarthritis (knee symptoms plus radiographically confirmed osteoarthritis) were compared with women without disease. MEASUREMENTS: Recalled date of symptom onset was used as the incident date of disease. Historical weight was defined as baseline body mass index up to 12 years before symptom onset. Change in body mass index was assessed at several intervals before the current examination. Odds ratios assessing the association between weight change and knee osteoarthritis were adjusted for age, baseline body mass index, history of previous knee injury, habitual physical activity level, occupational physical labor, smoking status, and attained education. RESULTS: Weight change significantly affected the risk for the development of knee osteoarthritis. For example, a decrease in body mass index of 2 units or more (weight loss, approximately 5,1 kg) over the 10 years before the current examination decreased the odds for developing osteoarthritis by over 50% (odds ratio, 0.46; 95% Cl, 0.24 to 0.86; P = 0.02). Among those women with a high risk for osteoarthritis due to elevated baseline body mass index (greater than or equal to 25), weight loss also decreased the risk (for 2 units of body mass index, odds ratio, 0.41; P = 0.02). Weight gain was associated with a slightly increased risk for osteoarthritis, which was not statistically significant. CONCLUSION: Weight loss reduces the risk for symptomatic knee osteoarthritis in women.

Aged↗