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PubMed2004

A new measure of placebo response and patient satisfaction in office encounters.

OBJECTIVES: Placebo response is defined as a change in health status resulting from the symbolic significance attributed by the patient or proxy to the physician encounter. Our goals were to validate the PR12 survey as a measure of placebo response and to analyze the placebo response as a discrete and measurable component of everyday office encounters with the otolaryngologist. STUDY DESIGN: This was a prospective, before-and-after clinical outcomes study of 95 children aged 6 months to 12 years conducted in an academic metropolitan pediatric otolaryngology practice. Caregivers completed the PR-12 survey at entry and at least 4 weeks later. The survey included 3 domains (4 questions each) reflecting the main components of the placebo response: meaningful explanation, care and concern, and mastery and control. PR-12 was correlated with longitudinal change in health status at least 1 to 2 months after the baseline visit. Outcome measures included direct and indirect measures of change in disease-specific quality of life and satisfaction with change. RESULTS: Test-retest reliability was fair for most PR-12 survey items (R = 0.41 to 0.76) but was higher for domains (0.60 to 0.66) and the overall survey score (0.66). PR-12 had excellent internal consistency (Cronbach's alpha 0.91) and appropriate construct validity. Caregiver satisfaction change at follow-up correlated with the PR-12 (r = -.25, P = 0.036). Conversely, no correlation was seen between the PR-12 and direct and indirect measures of change in disease specific quality of life. CONCLUSION: Placebo response is an important and potentially measurable aspect of clinical encounters. PR-12 is a promising first step at creating a brief, reliable, and valid instrument to assess the placebo response. SIGNIFICANCE: Reemphasizing the therapeutic potential of the doctor-patient relationship may improve quality of care and disease outcomes.

Child↗
PubMed2002

Monitoring bone density in hypogonadal men by quantitative phalangeal ultrasound.

Monitoring bone density (BMD) in hypogonadal and testosterone (T) substituted men is a major component of andrological therapy and is performed by methods that are cost-intensive and use radiation, such as quantitative computer tomography (QCT). Therefore, we assessed the feasibility of a more practical and inexpensive approach through application of phalangeal quantitative ultrasound (pQUS; IGEA DBM BP Sonic 1200, Sensweiler, Germany) in a cross-sectional study of 521 men, aged 18-91 years (224 healthy controls, 156 newly diagnosed hypogonadal, and 141 T substituted men). The method was compared with QCT of the lumbar spine in the first 80 patients. We evaluated longitudinal changes of amplitude-dependent speed-of-sound (AdSoS) in 54 hypogonadal men from the beginning of T substitution. AdSoS decreased with age (p < 0.0001) and with declining total T concentration, with a four to fivefold larger reduction in AdSoS for each nanomole-per-liter decrement in total T in the hypogonadal range (<12 nmol/L) compared with the eugonadal range (p < 0.0001). AdSoS was higher in eugonadal and substituted men than in hypogonadal patients (p < 0.0001, by analysis of covariance [ANCOVA]). Substituted men <50 years of age showed lower AdSoS than eugonadal men (p = 0.004) and untreated men with secondary hypogonadism had lower values than men with primary hypogonadism (p = 0.005). Therapeutic effects were seen regardless of age, diagnosis, or T substitution modality. In the longitudinal approach, AdSoS increased from 1986 +/- 93 to 2035 +/- 77 m/sec over 237 +/- 57 days with the highest gain in those men with initially the lowest values (p < 0.0001, by ANCOVA for repeated measurements). In comparison to QCT, patients with a lumbar content of hydroxylapatite of <100 mg/cm(3) were reliably identified by pQUS (cutoff level 1965 m/sec, T score -3.5 based on eugonadal subjects; receiver operating characteristics: area under the curve [AUC] 0.94, sensitivity 94.1, specificity 92%, p < 0.0001), but specific values of lumbar BMD could not be predicted by pQUS. pQUS represents a feasible, sensitive, and inexpensive method for assessing bone tissue in hypogonadal men over the full age range and also for monitoring the effects of T substitution.

Adolescent↗
PubMed1997

Longitudinal assessment of quality of life in acute psychiatric inpatients: reliability and validity.

This study examined the reliability, validity, and responsiveness of Lehman's Quality of Life Interview (QOLI) as an outcome measure on 981 acutely ill psychiatric inpatients assessed longitudinally at admission and discharge. Patients were stratified into five diagnostic (DX) (depressed bipolar, depressed unipolar, schizophrenia, mania, and other diagnoses) and two substance use disorder (SA) strata (with and without concurrent substance abuse/dependence) based on DSM-III-R criteria. There was good replication of the factor structure, excellent internal consistency, overall and within DX and SA groups. Intercorrelations showed that the functional and satisfaction indices measure unique aspects of the quality of life. The construct consistency of the QOLI was dependent upon psychiatric diagnosis and life domain. Intercorrelations of functional and satisfaction indices for patients with depression were greater than for manic patients. We demonstrated strong consistency of construct validity for family and social relation domains, but not safety or leisure activities. Construct validity was shown to hold longitudinally. Analyses of DX and SA group differences on satisfaction and functional indices of the 8 life domains supported discriminative validity: Depressed patients reported the most dissatisfaction, followed by schizophrenic patients, and manic patients reported the greatest satisfaction in most life domains. Patients with concurrent substance abuse generally reported less satisfaction and lower quality of life than patients without a dual diagnosis. Examination of longitudinal changes in satisfaction indicated the QOLI is responsive to changes in global life, leisure activities, living situation, and social relations from hospital admission to discharge (an average of 2 weeks). This study supports the use of the QOLI as an outcome measure to assess quality of life in acutely ill hospitalized psychiatric patients.

Activities of Daily Living↗
PubMed2001

Progressive histopathological changes in pancreatic islets of Zucker Diabetic Fatty rats.

Thus far, histopathological changes in the pancreatic islets of Zucker Diabetic Fatty (ZDF) rats, an animal model of type 2 diabetes mellitus (or non-insulin-dependent diabetes mellitus), have only been studied in male rats and in 18-weeks old rats or younger. In this study, we have examined in both male and female ZDF rats the histopathological changes longitudinally, from 6 to 32 weeks of age. We studied islet architecture and cellular distribution of the various islet hormones both in ZDF and control rats. In the ZDF rats, aging was initially associated with an enlargement of the islets. From 18 weeks onwards, no further enlargement was noted but islet boundaries became increasingly irregular, leading to the appearance of projections of endocrine cells into the surrounding exocrine tissue. At the islet boundaries as well as within the islets progressive fibrosis was observed with increasing amounts of collagen and reticular fibers. In the islets, staining intensity of both insulin and islet amyloid polypeptide (IAPP) increased slightly till 10 weeks of age and thereafter decreased rapidly. In contrast, the staining intensities of glucagon, somatostatin, and pancreatic polypeptide (PP) did not change. Even at the age of 32 weeks, just the beta-cells and not the other endocrine islet cells appear to be affected. In control rats, aging evoked only minor changes. Thus, we observed that during prolonged development of diabetes mellitus in both male and female ZDF rats histopathological changes in the pancreatic islets became progressively more severe, eventually leading to disintegration of the islets.

Aging↗
PubMed1995

Validation of an asthma quality of life diary in a clinical trial.

BACKGROUND: Quality of life (QOL) is commonly measured in asthma clinical trials by a questionnaire given before and after treatment. A structured asthma QOL daily diary provides more restricted information but on a daily basis. The validity and use of such a QOL diary was examined in a clinical trial in which two asthma treatments were compared. METHODS: The effects of low dose inhaled steroid (400 micrograms beclomethasone dipropionate, BDP) combined with the long acting beta 2 agonist salmeterol (100 micrograms) (n = 220) was compared with high dose inhaled steroid (1000 micrograms BDP) (n = 206) in asthmatic outpatients in a double blind, parallel group study. Outcome measures consisted of a combined diary for peak expiratory flow (PEF) rate, symptoms, and problems, and an asthma-specific QOL questionnaire, the Living with Asthma Questionnaire. RESULTS: The QOL diary correlated with the QOL questionnaire for both cross sectional and longitudinal assessments. Cross sectional correlations with PEF were higher for the QOL questionnaire than the QOL diary, but longitudinal correlations with PEF were higher for the diary than the questionnaire. Treatment with low dose steroid/salmeterol compared with high dose steroid produced better lung function, better QOL as measured by diary, and reduced night time wakenings, but treatment differences were not obtained with the QOL questionnaire nor for daytime symptoms. Diary assessed QOL was a better predictor of low PEF than diary assessed symptoms. Compliance with diary completion was good but there were floor or ceiling effects in the QOL diary records of about 25% of patients. CONCLUSIONS: Structured QOL diaries are valid instruments that appear to be more responsive to longitudinal change in clinical trials than a QOL questionnaire, but QOL questionnaires provide a more sensitive cross sectional measure of disease severity. Floor and ceiling effects are found in some patients' QOL diaries which limit their usefulness. QOL diary problem events occur during the troughs of a peak flow graph, while symptoms are more widely distributed with respect to peak flow.

Adolescent↗
PubMed1995

Calcium requirements of lactating Gambian mothers: effects of a calcium supplement on breast-milk calcium concentration, maternal bone mineral content, and urinary calcium excretion.

The calcium requirement for prolonged lactation was investigated in a randomized supplementation study of Gambian mothers consuming a low-calcium diet (7.1 mmol/d, or 283 mg/d). Sixty women were studied from 10 d to 78 wk of lactation, receiving calcium or placebo for the first 12 mo. The supplement increased average calcium intake by 17.9 mmol/d (714 mg/d). Supplementation had no effect on breast-milk calcium concentration or on maternal bone mineral content. Urinary calcium output was higher in supplemented than in unsupplemented mothers by 1.18 mmol/d (47 mg/d), P < or = 0.005. Longitudinal changes in urinary calcium output and bone mineral content made a substantial contribution to calcium requirements for lactation. This study suggests that, in women with low calcium intakes, there is no direct benefit from increasing calcium intake during lactation, and that physiological mechanisms operate to furnish calcium for breast-milk production.

Adolescent↗
PubMed2004

The effect of dialysis dose and membrane flux on nutritional parameters in hemodialysis patients: results of the HEMO Study.

BACKGROUND: The effect of standard or high dialysis dose and low or high dialysis flux on nutritional status was ascertained in 1846 maintenance hemodialysis patients enrolled in the HEMO Study. METHODS: Serum albumin levels, equilibrated protein catabolic rate, and postdialysis weight were obtained monthly, while adjusted protein and energy intake, self-reported appetite assessment, upper arm circumference, and calf circumference were obtained yearly. To account for patient attrition due to death or transfer, three statistical models were used to test the effects of the study interventions on longitudinal changes in nutritional parameters. RESULTS: During the first 3 years of follow-up, neither mean serum albumin levels, which declined by 0.21 g/dL, nor mean postdialysis weight, which declined by 2.7 kg, were significantly affected by either study intervention. Mean levels of all anthropometric measures declined during follow-up. For years 1, 2, and 3, the mean +/- SE declines in upper arm and calf circumferences were 0.35 +/- 0.16 cm (P= 0.031) and 0.31 +/- 0.13 (P= 0.015) cm less, respectively, in the high flux compared to the low flux group. Appetite scores and mean equilibrated protein catabolic rate also declined in all randomized groups; however, the average decline in equilibrated protein catabolic rate during years 1, 2, and 3 was 0.019 +/- 0.007 g/kg/day less in the high dose than the standard dose group (P= 0.007). There was no significant change in either mean energy or protein intake from diet records over time, and neither parameter was affected by the study interventions. CONCLUSION: Although the dose and flux interventions may subtly influence certain nutritional parameters, neither intervention prevented deterioration in nutritional status over time.

Adult↗
PubMed2003

Extrastriatal dopamine D(2) receptors in Parkinson's disease: a longitudinal study.

Most antiparkinsonian drugs are known to act through central dopamine D(2) receptor agonism. A previous longitudinal positron emission tomography (PET) study has indicated that, in the striatum of Parkinson's disease (PD) patients, dopamine D(2) receptor binding declines at a relatively fast annual rate of 2-4% (compared to the rate of <1%/year in healthy individuals). In the present study, the examination of longitudinal changes in D(2) receptors was extended to extrastriatal brain regions in PD. Eight early PD patients were examined twice with PET, approximately 3 years apart, using a high-affinity extrastriatal D(2)/D(3) receptor tracer, [(11)C]FLB 457. Both the MRI-referenced region-of-interest method and the voxel-based statistical analysis method were used independently in the analysis. Regional D(2)-like availabilities (binding potentials) in the left dorsolateral prefrontal cortex, the left temporal cortex and the left and right medial thalami were significantly decreased at the second examination by 20-37% (corresponding to an annual decline of 6-11%). Thus, the annual loss of extrastriatal D(2) availability in PD is up to three times faster than the rate previously reported in the putamen. Our longitudinal study shows first evidence concerning cortical D(2) receptor loss in the progression of PD, although it is not possible to distinguish between the effects of the therapy and the disease.

Aged↗
PubMed1986

Lung function after acute chlorine exposure.

Chlorine gas, spreading from a train derailment, caused the deaths of 8 persons and the hospitalization of 23 with sublethal respiratory injuries. Twenty-five others had at least one sign of lower respiratory abnormality but were not hospitalized. One hundred thirteen who were examined for gas effects in the forty-eight hours after exposure, including 20 of 23 of those hospitalized and 21 of 25 of those not hospitalized but with respiratory abnormality, participated in follow-up studies. Probability of admission to hospital was related to distance from the spill, but by 3 wk after exposure there was no detectable difference in lung function relating to distance or apparent severity of injury. In 60 adults tested multiple times over the following 6 yr, longitudinal change in lung function showed expected differences related to smoking but none related to distance or severity of injury. The average annual change in FEV was -34 ml/yr in current smokers and -18 ml/yr in ex and never-smokers. The lack of a discernible chlorine effect in this cohort accords with the findings in most previous studies. Without pre-exposure measurements, a single, lasting reduction in lung function cannot be excluded, but there is no evidence for a persisting abnormal rate of decline.

Accidents↗
PubMed1984

Genetic variation and craniofacial growth in inbred rats.

There has been no experimental study clarifying the contribution of genetic variation to craniofacial growth on a longitudinal basis, although its importance is generally accepted. Utilizing diallel crosses of five strains of inbred rats, the present study concerns an estimation of the contribution genetic variation makes to the longitudinal change of craniofacial size. The overall sizes of craniofacial complex components of F1-offspring rats were investigated postnatally by means of roentgenographic cephalometry, and quantitative genetic analysis was performed by the method of Wearden [1964]. It was revealed that the relative contributions of the genetic and environmental components to total variance in craniofacial size varied with age and that the genetic component of variance significantly increased until the 80th day. On the other hand, the maternal component of variance showed the maximum value during the early periods of postnatal growth (ie, the 10th to 25th day), gradually declining thereafter to a very small amount by the 80th day. The environmental component of variance increased slightly and gradually with age through the experimental period. In conclusion it appeared that genetic variation became more significant during longitudinal growth of the craniofacial complex as the maternal effects diminished.

Age Factors↗
PubMed1996

Secretory phospholipase A2 as an index of disease activity in rheumatoid arthritis. Prospective double blind study of 212 patients.

OBJECTIVE: A limited retrospective study of patients with rheumatoid arthritis (RA) found that serum secreted phospholipase A2 (sPLA2) activity correlates with disease activity (J Rheumatol 1988; 15:1351-5). To assess the strength of this relationship we investigated prospectively 212 patients with RA using a double blind approach. METHODS: 212 patients who fulfilled the 1987 ACR criteria for RA had 420 clinical and laboratory assessments. 65 patients were assessed on one occasion and 147 on multiple occasions (a mean of 2.41 visits/patient). sPLA2 was tested by an independent investigator. RESULTS: sPLA2 activity assessed as a dichotomous variable (less or more than mean +/- 2 SD) correlated highly (p < 0.005) with Lansbury index, number of effusions, number of damaged joints, erythrocyte sedimentation rate (ESR), platelet count, and low hemoglobin. Univariate and multivariate regression analyses showed significant correlations with Lansbury index, active and effused joints, hemoglobin, platelet count, and ESR. The best correlation was observed in a multivariate model that included Lansbury index, ESR, and platelet count (r = 0.60). Analysis of longitudinal changes in sPLA2 activity in 147 patients assessed more than once showed that sPLA2 correlates significantly with Lansbury index, active and effused joints, and hemoglobin. CONCLUSION: Serum sPLA2 activity correlates significantly with Lansbury index, active and effused joints, ESR, platelet court, and hemoglobin. Thus, sPLA2 can serve as an index of disease activity in RA.

Adolescent↗
PubMed2005

Longitudinal assessment of quality of life in patients with type 2 diabetes and self-reported erectile dysfunction.

OBJECTIVE: In the context of the QuED (Quality of Care and Outcomes in Type 2 Diabetes) project, we evaluated the longitudinal changes over 3 years in quality of life (QoL) in patients with type 2 diabetes according to the presence or the development of erectile dysfunction (ED). RESEARCH DESIGN AND METHODS: Patients were requested to fill in a questionnaire investigating the presence of ED and QoL (SF-36 Health Survey, depression symptoms [Center for Epidemiologic Studies-Depression], and quality of sexual life) every 6 months for 3 years. The analyses were based on multilevel models, adjusted for patient clinical and sociodemographic characteristics. RESULTS: The study involved 1,456 patients, of whom 34% reported frequent erectile problems at baseline; 192 developed ED during the follow-up. No changes in QoL measures were detected in patients without ED; in those with ED at baseline, a worsening in all SF-36 scales was observed, reaching statistical significance for physical functioning (P = 0.03). Among patients who developed ED during the study, a deterioration in all SF-36 dimensions and a worsening in depressive symptoms preceded the development of ED. The onset of ED was associated with a further marked worsening in physical functioning (P = 0.0008), general health perception (P = 0.02), and social functioning (P = 0.04) on SF-36 subscales, as well as in the summary physical and mental components scores (P = 0.04 and P = 0.07, respectively). The development of ED was also associated with a highly significant increase in depressive symptoms (P = 0.001) and a marked decrease in quality of sexual life (P < 0.0001). CONCLUSIONS: This longitudinal study documents for the first time the impact of ED onset on several aspects of QoL in patients with type 2 diabetes. The study also shows that QoL tended to further decrease during 3 years in patients with ED at baseline but not in those without this condition.

Aged↗
PubMed2004

Longitudinal distribution of Copepoda populations in the transition zone of Paranapanema River and Jurumirim Reservoir (São Paulo, Brazil) and interchange with two lateral lakes.

Longitudinal changes in composition, abundance, and distribution of copepods were studied at the transition zone of Paranapanema River-Jurumirim Reservoir (SP, Brazil). The interchange of biotic material between marginal lakes and the river system was also examined. Water samples were obtained from 6 stations along a stretch of 13 km of the Paranapanema River, from an upstream reach with high water velocity up to the river mouth into Jurumirim Reservoir. Two other sites in lateral lakes were also sampled. Nine copepod taxa were identified: 3 calanoids (Argyrodiaptomus furcatus Sars, Notodiaptomus iheringi Wright, and N. conifer Sars) and 6 cyclopoids (Eucyclops Claus, Microcyclops Claus, Mesocyclops longisetus Thiébaud, Thermocyclops decipiens Fischer, T. minutus Lowndes, and Paracyclops Claus). Harpacticoids were also collected. Calanoid and cyclopoid nauplii and copepodids, and harpacticoids were the most abundant organisms. In general, there was a longitudinal decrease in copepod abundance, whereas an increase was detected near the lakes. The abundance of most copepods was inversely correlated with current velocity and suspended solids. Higher abundance was observed in the river main course during the rainy season, during which there is a higher connectivity between the lakes and the main river. This promotes exportation of biologic material from marginal lakes to the river system, a biotic exchange reflecting the importance of marginal lakes to the river community structure.

Animals↗
PubMed1998

Longitudinal evaluation of the complexed-to-total prostate specific antigen ratio in men with prostate disease. Effect of treatment.

The longitudinal changes in the complexed-to-total prostate specific antigen (PSA) ratio were evaluated in 90 men with benign prostatic hyperplasia (BPH) and 50 men with prostate cancer. The influence of treatment on this ratio was studied in 45 BPH patients and 50 patients with prostate cancer. Using a cut-off of 0.80 for the complexed-to-total PSA ratio, the large majority of prostate cancer patients had a ratio above the cut-off before treatment in serial determinations, whereas most BPH patients had a ratio consistently below that value. However, the few prostate cancer patients who had a ratio < or = 0.80 showed this low ratio in serial determinations, as did BPH patients who had a ratio > or = 0.80. During treatment, the ratio significantly decreased in 43 of the 50 patients with prostate cancer in parallel with the decrease in total PSA, and 34 of the 41 patients that had a pretreatment ratio > 0.80 showed a ratio < or = 0.80 during hormonal therapy. Our results show that neither the physiological changes in total and complexed PSA nor the treatment of BPH patients change the diagnostic efficacy of the complexed-to-total PSA ratio, whereas in prostate cancer patients under hormonal therapy, the ratio decreased in parallel with the decrease in total PSA. This suggests that, apart from improving the diagnostic efficacy of total PSA, the complexed-to-total PSA ratio could also be used to monitor BPH patients for newly developed tumours or to monitor therapy in patients with prostate cancer.

Antineoplastic Agents, Hormonal↗
PubMed1997

Quality of life for children with otitis media.

OBJECTIVE: To evaluate changes in health-related quality of life for children with otitis media. DESIGN: Cohort study using a 6-item quality-of-life survey (OM-6) representing the domains of physical suffering, hearing loss, speech impairment, emotional distress, activity limitations, and caregiver concerns. SETTING: Hospital-based pediatric otolaryngology practice in a metropolitan area. PATIENTS: One hundred eighty-six children aged 6 months to 12 years (median age, 3.4 years) with chronic otitis media with effusion or recurrent acute otitis media. INTERVENTION: The OM-6 was completed at entry by the child's caregiver and again at least 4 weeks after routine clinical care. Otoscopic findings, static admittance, tympanometric width, audiometric thresholds, and ear-related global quality of life (10-point visual scale) were recorded concurrently. MAIN OUTCOME MEASURES: Test-retest reliability, construct validity, and responsiveness to longitudinal change of the OM-6 survey score (mean value of the 6 items). RESULTS: Excellent test-retest reliability was obtained for the survey score (R=0.87) and individual survey items (R> or =0.71). The median survey score was 2.8 (95% confidence interval, 2.7-3.0) of a maximum 7.0, with higher values indicating poorer quality of life. Construct validity was shown by significant correlations between the survey score and global ear-related quality of life (R=-0.64), between physical suffering and physician visits in the past month (R=0.47), and between caregiver concerns and antibiotics consumed in the past month (R=0.26). The mean change in survey scores after tympanostomy tubes was 1.7, with a standardized response mean of 1.7 (95% confidence interval, 1.4-2.0), indicating large responsiveness to change. The change score was reliable (R=0.82) and correlated well with the degree of reported clinical change (R=0.66). CONCLUSIONS: The OM-6 is a valid, reliable, and responsive measure of quality of life for children with otitis media. The brevity and ease of administration make the OM-6 ideal for use in outcomes studies, clinical trials, and routine clinical care.

Activities of Daily Living↗
PubMedDate not supplied

Metabolic bone disease in adults receiving long-term parenteral nutrition: longitudinal study with regional densitometry and bone biopsy.

A syndrome of bone pain and fractures has been described in patients receiving long-term support from parenteral nutrition containing large quantities of aluminium or vitamin D2. Whether this same syndrome occurs in patients supported by current therapeutic regimens is controversial. In this study, bone health was longitudinally evaluated over 7 to 61 months in 14 subjects maintained on long-term parenteral nutrition. The parameters of bone health evaluated included bone mass as measured by single and dual photon absorptiometry and quantitative histomorphometry of bone biopsies. There was a striking heterogeneity in baseline measures of bone health. Mean bone density of parenteral nutrition patients was significantly below expected values on entry into the study at both the distal radius (z score = -0.76 +/- 0.27) and the lumbar spine (z score = -1.17 +/- 0.27). Mean areal density at the forearm was less severely depressed (z score = -0.62 +/- 0.34). The longitudinal changes in bone density and morphology were heterogeneous, with some subjects showing deterioration, others improvement, and still others no change. We conclude that patients already established on parenteral nutrition frequently have osteopenia. The group as a whole did not demonstrate normalization of the osteopenia, but our results also suggest that current parenteral nutrition formulations low in aluminum and vitamin D2 do not necessarily cause worsening of bone health. The etiology of this clinical syndrome merits additional study.

Adult↗
PubMed2005

The relationship between body composition and knee cartilage volume in healthy, middle-aged subjects.

OBJECTIVE: Although obesity is widely accepted as a risk factor for knee osteoarthritis, it is not clear whether individual components of body composition, such as the mass and distribution of muscle and fat, are associated with development of the disease. This study examined the effect of measures of body composition on the longitudinal change in tibial cartilage volume. METHODS: Body composition, assessed via dual x-ray absorptiometry, and tibial cartilage volume, assessed via magnetic resonance imaging, were measured in 86 healthy men and women who were mid-life in age. Change in tibial cartilage volume was assessed by imaging each knee 2 years after the baseline measurement and determining the difference from baseline in tibial cartilage volume. Correlations were determined between the muscle and fat mass of the arm, leg, and total body and the volume of the lateral- and medial-tibial cartilage, as well as the change in tibial cartilage volume over 2 years, after adjusting for confounders. RESULTS: There was a significant association between muscle mass and the medial-tibial cartilage volume, independent of age, sex, body mass index, tibial bone area, and level of physical activity. Although there was a positive association between muscle mass and the lateral-tibial cartilage volume, this did not persist after adjustment for confounders. Loss of muscle mass was associated with an increased loss of medial- and lateral-tibial cartilage over 2 years, after adjusting for confounders. No relationship was apparent between fat mass and either medial- or lateral-tibial cartilage volume, or between fat mass and change in either medial- or lateral-tibial cartilage volume over 2 years, after adjusting for confounders. CONCLUSION: Muscle mass is an independent predictor of medial-tibial cartilage volume in healthy people in mid-life and is associated with a reduction in the rate of loss of tibial cartilage. This suggests that increased muscle mass may be protective against the onset of osteoarthritis.

Absorptiometry, Photon↗
PubMed1995

Vascular changes following mucoperiosteal flap surgery: a fluorescein angiography study in dogs.

This study was undertaken to determine the vascular changes which occur following mucoperiosteal flap surgery where two different suturing techniques were employed. In four healthy adult mongrel dogs, buccal and lingual full-thickness envelope flaps were reflected in the mandibular quadrants following intravicular incisions from the first premolar to the first molar. The flaps were immediately readapted and primary closure was achieved by the horizontal mattress suturing technique in one quadrant and the direct interrupted suturing technique in the contralateral quadrant of each dog. A simple photographic system was developed for recording the in vivo gingival circulation depicted by fluorescein angiography just prior to surgery and then after surgery on days 1, 3, 7, 10, 14, and 21. The flaps were divided into three interproximal and two mid-buccal sites for analysis and the intracapillary and diffusion extent of dye fluorescence was accurately quantified by computerized planimetry. As healing progressed, longitudinal changes relative to presurgical baseline were analyzed by paired t-test. Cross-sectional comparisons utilizing Student t-test allowed for evaluating differences between the two suturing techniques as well as differences between interproximal versus mid-buccal sites at each postsurgical day. It was found that the simple act of raising a mucoperiosteal envelope flap initiates significant vascular trauma. Statistically significant reductions in flap circulation relative to presurgical baseline lasted for at least 3 days but persisted for 7 days at the interproximal sites. Flap diffusion (extravascular leakage) recovered sooner and extended over a significantly greater area of the flap than did intracapillary flap circulation during the early period of healing.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗