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P J O'Connor

Publications and source records attributed to P J O'Connor.

At least 19 recordsLinked to original sources
PubMed2006

Advanced imaging in rheumatoid arthritis. Part 1: synovitis.

Rheumatoid arthritis (RA) is a chronic and progressive inflammatory disorder primarily affecting the synovium. We now recognise that conventional radiographic images show changes of rheumatoid arthritis long after irreversible joint damage has occured. With the advent of powerful disease-modifying drugs, there is a need for early demonstration of rheumatoid arthritis and a need to monitor progress of the disease and response to therapy. Advanced imaging techniques such as ultrasound and MRI have focussed on the demonstration and quantification of synovitis and erosions and allow early diagnosis of RA. The technology to quantify synovitis and erosions is developing rapidly and now allows change in disease activity to be assessed. However, problems undoubtedly exist in quantification techniques, and this review serves to highlight them. Much of the literature on advanced imaging in RA appears in rheumatological journals and may not be familiar to radiologists. This review article aims to increase the awareness of radiologists about this field and to encourage them to participate and contribute to the ongoing development of these modalities. Without this collaboration, it is unlikely that these modalities will reach their full potential in the field of rheumatological imaging. This review is in two parts. The first part addresses synovitis imaging. The second part will look at advanced imaging of erosions in RA.

Arthritis, Rheumatoid↗
PubMed2006

Advanced imaging in rheumatoid arthritis: part 2: erosions.

Rheumatoid arthritis (RA) is a chronic and progressive inflammatory disorder primarily affecting the synovium. We now recognise that conventional radiographic images show changes of rheumatoid arthritis late after irreversible joint damage has occured. With the advent of powerful disease-modifying drugs there is a need for early demonstration of rheumatoid arthritis and to monitor progress of the disease and response to therapy. Advanced imaging techniques such as ultrasound and MRI have focussed on the demonstration and quantification of synovitis and erosions and allow early diagnosis of RA. The technology to quantify synovitis and erosions is developing rapidly and now allows change in disease activity to be assessed. However, problems undoubtedly exist in quantification techniques and this review serves to highlight them. Much of the literature on advanced imaging in RA appears in rheumatological journals and may not be familiar to radiologists. This review article aims to increase the awareness of radiologists to this field and to encourage them to participate and contribute to the ongoing development of these modalities. Without this collaboration it is unlikely that these modalities will reach their full potential in the field of rheumatological imaging. This review is in two parts. This first part addresses synovitis imaging. The second part will look at advanced imaging of erosions in RA.

Arthritis, Rheumatoid↗
PubMed2006

Former college artistic gymnasts maintain higher BMD: a nine-year follow-up.

INTRODUCTION: If higher bone gains acquired from weight-bearing sports during growth persist into old age, the residual benefits could delay or even prevent osteoporotic fractures. The purpose of this study was to determine if the higher areal bone mineral density (aBMD) observed 15 years after competitive training and competition in former female college artistic gymnasts (GYM) compared with controls (CON) is maintained nine years later in this same cohort approaching menopause. In this 9-year follow-up, aBMD changes were also compared between GYM (n=16; aged 45.3+/-3.3 years) and CON (n=13; aged 45.4+/-3.8 years). METHODS: Total body, lumbar spine, proximal femur, femoral neck, leg, and arm aBMD were assessed at baseline and follow-up using dual-energy X-ray absorptiometry (DXA), (Hologic QDR-1000W). GYM had higher aBMD at all sites at follow-up (P<0.05; eta (2)>0.14). RESULTS: While there were no significant differences between groups for percent changes in aBMD at the total body, lumbar spine, total proximal femur, femoral neck, and arm, the change in leg aBMD was significantly different between GYM and CON (P=0.05; eta (2)=0.14). CONCLUSIONS: Former female college artistic gymnasts maintained significantly higher aBMD than controls 24 years after retirement from gymnastics training and competition. This study provides greater insight into the effects of past athletic participation on skeletal health in women approaching menopause.

Absorptiometry, Photon↗
PubMed2006

Presence of significant synovitis in rheumatoid arthritis patients with disease-modifying antirheumatic drug-induced clinical remission: evidence from an imaging study may explain structural progression.

OBJECTIVE: More timely and effective therapy for rheumatoid arthritis (RA) has contributed to increasing rates of clinical remission. However, progression of structural damage may still occur in patients who have satisfied remission criteria, which suggests that there is ongoing disease activity. This questions the validity of current methods of assessing remission in RA. The purpose of this study was to test the hypothesis that modern joint imaging improves the accuracy of remission measurement in RA. METHODS: We studied 107 RA patients receiving disease-modifying antirheumatic drug therapy who were judged by their consultant rheumatologist to be in remission and 17 normal control subjects. Patients underwent clinical, laboratory, functional, and quality of life assessments. The Disease Activity Score 28-joint assessment and the American College of Rheumatology remission criteria, together with strict clinical definitions of remission, were applied. Imaging of the hands and wrists using standardized acquisition and scoring techniques with conventional 1.5T magnetic resonance imaging (MRI) and ultrasonography (US) were performed. RESULTS: Irrespective of which clinical criteria were applied to determine remission, the majority of patients continued to have evidence of active inflammation, as shown by findings on the imaging assessments. Even in asymptomatic patients with clinically normal joints, MRI showed that 96% had synovitis and 46% had bone marrow edema, and US showed that 73% had gray-scale synovial hypertrophy and 43% had increased power Doppler signal. Only mild synovial thickening was seen in 3 of the control subjects (18%), but no bone marrow edema. CONCLUSION: Most RA patients who satisfied the remission criteria with normal findings on clinical and laboratory studies had imaging-detected synovitis. This subclinical inflammation may explain the observed discrepancy between disease activity and outcome in RA. Imaging assessment may be necessary for the accurate evaluation of disease status and, in particular, for the definition of true remission.

Adult↗
PubMed2005

Ultrasonography for rheumatologists: the development of specific competency based educational outcomes.

BACKGROUND: A competency based approach to the education of rheumatologists in musculoskeletal ultrasonography (MSK US) ensures standards are documented, transparent, accountable, and defensible, with clear benefit to all stakeholders. Specific competency outcomes will facilitate informed development of a common curriculum and structured programme of training and assessment. OBJECTIVE: To determine explicit competency based learning outcomes for rheumatologists undertaking MSK US. METHODS: International experts in MSK US, satisfying specific selection criteria, were asked to define the minimum standards required by a rheumatologist to be judged competent in MSK US. They reviewed 115 MSK US skills, comprising bone and soft tissue pathology, in seven joints regions of the upper and lower limbs, and rated their relative importance according to specific criteria. These data are presented as specific educational outcomes within designated competency categories. RESULTS: 57 expert MSK US practitioners were identified and 35 took part in this study. Ten generic core competency outcomes were recognised including physics, anatomy, technique, and interpretation. Regarding specific regional competencies, 53% (61/115) were considered "must know" core learning outcomes, largely comprising inflammatory joint/tendon/bone pathology and guided procedures; 45% (52/115) were required at an intermediate/advanced level (18/115 "should know", 34/115 "could know"), and 2% (2/115) were deemed inappropriate/unnecessary for rheumatologist ultrasonographers. CONCLUSIONS: This is the first study to developing a competency model for the education of rheumatologists in MSK US based on the evidence of international experts. A specific set of learning outcomes has been defined, which will facilitate future informed education and practice development and provide a blueprint for a structured rheumatology MSK US curriculum and assessment process.

Clinical Competence↗
PubMed2005

Prevalence of spinal cord injury in Australia.

STUDY DESIGN: Cohort study, based on cases of spinal cord injury (SCI) that occurred between 1986 and 1997 (n=2959). OBJECTIVES: To estimate prevalence historically, currently and into the future. SETTING: Australia. METHODS: Prevalence was estimated on the basis of (1) historical data concerning survival and the relationship between the incidence of fatalities and SCI, (2) information on SCI incidence and survival 1986-1997, and (3) forecasts of incidence and population growth from 1997 to 2021 and consideration of survival. RESULTS: It was estimated that the prevalence of SCI in Australia was in the range 8096-9614 cases by 1985. By 1997, this had increased to nearly 10,000 and the prevalence rate was more than 681 per million of population. By 2021, this could increase to nearly 12,000 if age-specific SCI incidence rates continued at average values evident over the period 1986-1997 and national population projections applied. In addition, there would be more elderly SCI cases due to the ageing of the national population. The prevalent population could be reduced to less than 7000 if the incidence rate was reduced by -3% p.a. CONCLUSION: The prevalence of SCI in Australia has increased and it will continue to increase unless measures are taken to control incidence. The case mix will change due to the ageing of the population, and treatment services will need to be prepared for a larger and more elderly prevalent population. It was suggested that consideration should be given to a national health and welfare goal to reduce the SCI incidence rate by -3% p.a., focusing in particular on the prevention of transport crashes and falls.

Adolescent↗
PubMed2005

Differentials in poisoning rates of young Australian children according to residential location and geographical remoteness.

OBJECTIVES: To assess differentials in the poisoning rates of children aged 0-4 years according to residential location and geographical remoteness. DESIGN: Cross sectional study based on hospitalizations. SETTING: Australia. SUBJECTS: Children aged 0-4 years admitted to hospital due to poisoning during the financial year 1996-97. MAIN OUTCOME MEASURES: Crude rates of hospitalization. RESULTS: The rate of hospitalization due to poisoning peaked in the third year and second year of life for medicinal and non-medicinal substances respectively. Rates were significantly higher among children aged 0-4 years residing in rural and remote areas when compared with those residing in metropolitan areas, and rate differentials increased with geographical remoteness. CONCLUSIONS: The observed differentials suggest the need for targeted research and prevention efforts aimed at rural and remote area communities. A detailed empirical study is recommended, involving the assessment of risk factors and an in-home hazard checklist, as a precursor to any intervention program.

Australia↗
PubMed2004

Adductor-related groin pain in athletes: correlation of MR imaging with clinical findings.

OBJECTIVE: To evaluate gadolinium-enhanced MR imaging in athletes with chronic groin pain and correlate with the clinical features. DESIGN AND PATIENTS: MR examinations performed in 52 athletes (51 male, 1 female; median age 26 years) with chronic groin pain and 6 asymptomatic control athletes (6 male; median age 29 years) were independently reviewed by two radiologists masked to the clinical details. Symptom duration (median 6 months) and clinical side of severity were recorded. Anatomical areas in the pelvis were scored for abnormality (as normal, mildly abnormal or abnormal) and an overall assessment for side distribution of abnormality was recorded, initially without post-gadolinium sequences and then, 3 weeks later (median 29 days), the post-gadolinium sequences only. Correlation between radiological and clinical abnormality was calculated by Spearman's correlation. RESULTS: Abnormal anterior pubis and enthesis enhancement significantly correlated with clinical side for both radiologists (both P=0.008). Abnormal anterior pubis and adductor longus enthesis oedema was significant for one radiologist ( P=0.009). All other features showed no significant correlation ( P>0.05). In the control cases there was no soft tissue abnormality but symphyseal irregularity was present ( n=2). For both radiologists assessment of imaging side severity significantly correlated with clinical side for post-gadolinium ( P=0.048 and P=0.023) but not non-gadolinium sequences ( P>0.05). CONCLUSION: The extent and side of anterior pubis and adductor longus enthesis abnormality on MR imaging significantly and reproducibly correlates with the athletes' current symptoms in chronic adductor-related groin pain.

Adolescent↗
PubMed2004

Effects of Schistosoma haematobium infection on drug-metabolizing enzymes in human bladder cancer tissues.

The mixed function oxidase system includes the phase I drug oxidation proteins e.g. aryl hydrocarbon hydroxylase (AHH), N-nitrosodimethylamine-N-demethylase I (NDMA-dI) and cytochrome b5 which metabolize most carcinogens and xenobiotics into less and/or more active intermediates. These were determined in human bladder tissues diagnosed as bladder cancer only (10 samples) and bladder cancer associated with Schistosoma haematobium (12 samples) and normal bladder tissues (12 samples). In addition to the above enzymes, agents involved in Phase II drug metabolism e.g. glutathione and glutathione S-transferase as well as free radicals (detected as thiobarbituric acid-reactive substances, TBARS) were also determined in these tissues samples. AAH and NDMA-dI, cytochrome b5, and glutathione S-transferase activity decreased by 42, 28, 47 and 32%, respectively, in human bladder cancer tissues. In bladder cancer tissues associated with S. haematobium infection NDMA-dI and GST activity decreased further by 65 and 56%, respectively, whereas AHH activity increased by 50% and levels of reduced glutathione also increased by 43% in cancer tissue and by 29% in schistocome infected bladder cancer tissue. The level of free radicals also increased significantly (by 57%) in infected bladder cancer tissue but not at all in non-infected cancer tissue. Alterations in the activity of phase I and II of drug-metabolizing enzymes in human bladder tissues as a result of S. haematobium infection may therefore change the bladder's capacity to detoxify many endogenous compounds and may also potentiate the deleterious effects of bladder carcinogens, (e.g. N-nitrosamines) which are known to be present in relatively large quantities in the bladder of patients with schistosomiasis. The present study thus provides new insights into mechanisms for the genesis of bladder cancer initiated in association with schistosomiasis.

Adult↗
PubMed2004

Trait anxiety predicts panic behavior in beginning scuba students.

Recreational scuba diving is associated with a significant number of fatalities and decompression illnesses each year, and there is evidence that permanent neuropsychological injury can occur in divers. There is also evidence that the principal cause of decompression illness and fatalities in divers is rapid ascent, and it appears that the primary stimulus for rapid ascent is panic. The primary purpose of this investigation was to evaluate the extent to which an objective measure of trait anxiety could be effective in predicting panic behavior in students undergoing scuba training. Trait anxiety was assessed at the outset of scuba instruction in 42 students, and the instructor recorded instances of panic behavior during the 4-month course. It was predicted that individuals scoring 39 or greater on the trait anxiety sub-scale of the State-Trait Anxiety Inventory would be more likely to experience panic behavior than individuals with scores below this cut-off. Predictions and actual recordings of panic behavior were performed independently using a blinded paradigm. Eleven of the students exhibited panic behavior on two or more occasions during the instruction, and 35 of 42 (83 %) predictions were accurate (p < 0.001). It is concluded that an objective measure of trait anxiety can be employed a priori for prediction of panic behavior in beginning scuba students.

Adult↗
PubMed2003

Cerebrovascular reactivity to carbon dioxide in sepsis syndrome.

Cerebral dysfunction in sepsis is common in critically ill adults. However, little is known of the effects of sepsis on cerebral haemodynamics. We studied 12 sedated and ventilated patients in whom sepsis had been established for > 24 h. Transcranial Doppler measurements of the middle cerebral artery flow velocity were made at normocapnia, then hypocapnia (-1 kPa) and hypercapnia (+1 kPa). From these data, cerebrovascular reactivity to carbon dioxide was calculated. Variables indicating disease severity, systemic cardiovascular status and outcome were also recorded. We found significant changes in cerebrovascular reactivity to carbon dioxide. Only three of 12 patients had a cerebrovascular reactivity to carbon dioxide in the normal range; seven patients had a reduced cerebrovascular reactivity to carbon dioxide, whereas in two patients it was raised. In this smaD sample, we could not find any trend of association between altered cerebrovascular reactivity to carbon dioxide and severity of illness, cardiovascular status or outcome. This study suggests that established sepsis profoundly affects the vascular tone and reactivity, not only of the systemic circulation, but also of the cerebral vasculature.

Adult↗
PubMed2002

Comparative assessment of leflunomide and methotrexate for the treatment of rheumatoid arthritis, by dynamic enhanced magnetic resonance imaging.

OBJECTIVE: Ethical constraints on the conduct of placebo-controlled trials evaluating new therapies for serious chronic diseases, such as rheumatoid arthritis (RA), indicate the need for discerning methods to assess treatment effect in active-controlled clinical trials. Dynamic gadolinium-enhanced magnetic resonance imaging (DEMRI) is a sensitive technique for the detection of synovial inflammation in RA. Therefore, this investigation was undertaken to evaluate DEMRI as an efficacy assessment tool for differentiating treatment effect in a randomized, active-controlled trial comparing leflunomide and methotrexate. METHODS: Patients with active RA (n = 39) were randomized in a 2-center, prospective, double-blind clinical trial to receive either leflunomide (n = 18) or methotrexate (n = 21) therapy for 4 months. DEMRI scans were obtained at baseline and at 4 months, and the initial rate of enhancement (IRE) and the maximal signal intensity (SI) enhancement (ME) were calculated from the SI curves. Clinical improvement was assessed by conventional outcome measures. RESULTS: Thirty-four patients (17 treated with leflunomide and 17 with methotrexate) had usable baseline and end point DEMRI scans. Leflunomide treatment was associated with a significantly greater improvement in IRE compared with methotrexate treatment (P < 0.05). Average values of ME indicated reduction of inflammation with both leflunomide and methotrexate. The improvement in clinical signs and symptoms, as measured by traditional assessments, was comparable for both active treatments. CONCLUSION: Results of this study validate the sensitivity of DEMRI in detecting inflammatory changes in active RA in response to treatment. Improvement in synovial inflammation as measured by IRE was significantly better with leflunomide than with methotrexate over 4 months of therapy.

Adult↗
PubMed2002

Changes in the expression of cytochrome P450 isozymes and related carcinogen metabolizing enzyme activities in Schistosoma mansoni-infected mice.

Mixed-function oxidase enzymes metabolize most xenobiotic agents. Western blotting was used to investigate the effect of Schistosoma mansoni infection on the expression of various cytochrome P450 (CYP) isozymes and specific enzyme assays to study related metabolic functions in mouse liver microsomes. Male BK-TO mice were infected with 200 cercariae per mouse and their livers were assayed at 6, 15, 30 and 45 days post-infection (p.i.) and compared with appropriately matched controls. The expression of each of the CYP isozymes (1A1, 2B1/2, 2C6, and 4A) was either unaffected or transiently increased up to 30 days post-infection. By 45 days, a significant loss of signal was observed, particularly for CYP 1A1 and 2B1 /2 where no signal could be detected. Evidence supporting these findings was obtained from enzyme assays specific for particular CYP isozymes. The activity of ethoxyresorufin O-deethylase (CYP 1A1) was reduced by 97% and that of pentoxyresorufin O-depentylase (CYP 2B1 /2) by 96% at 45 days p.i. Similarly, the activity of ethoxycoumarin hydroxylase was progressively reduced over the period under study. It is believed that N-nitrosamines are activated principally by N-nitrosodimethylamine N-demethylase I which was significantly increased at both 30 and 45 days p.i. To further investigate metabolic competency following S. mansoni infection, the in vitro binding of benzo(a)pyrene metabolites to DNA was measured, using isolated liver microsomes to activate benzo(a)pyrene. Benzo(a)-pyrene-DNA adduct formation was markedly increased at 6,15 and 30 days with a maximum at 15 days, but decreased at 45 days p.i. It was concluded that S. mansoni infection changes the expression of different CYP isozymes and also the activity of phase I drug-metabolizing enzymes at different periods of infection and may thus change the liver's capacity to activate or detoxify many endogenous and exogenous compounds. Such alterations may also change the therapeutic actions of drugs that are primarily metabolized by the P450 system, when administered to patients with schistosomiasis.

Animals↗
PubMed2001

Host determinants of DNA alkylation and DNA repair activity in human colorectal tissue: O(6)-methylguanine levels are associated with GSTT1 genotype and O(6)-alkylguanine-DNA alkyltransferase activity with CYP2D6 genotype.

There is increasing evidence that alkylating agent exposure may increase large bowel cancer risk and factors which either alter such exposure or its effects may modify risk. Hence, in a cross-sectional study of 78 patients with colorectal disease, we have examined whether (i) metabolic genotypes (GSTT1, GSTM1, CYP2D6, CYP2E1) are associated with O(6)-methyldeoxyguanosine (O(6)-MedG) levels, O(6)-alkylguanine-DNA alkyltransferase (ATase) activity or K-ras mutations, and (ii) there was an association between ATase activity and O(6)-MedG levels. Patients with colon tumours and who were homozygous GSTT1(*)2 genotype carriers were more likely than patients who expressed GSTT1 to have their DNA alkylated (83 versus 32%, P=0.03) and to have higher O(6)-MedG levels (0.178+/-0.374 versus 0.016+/-0.023 micromol O(6)-MedG/mol dG, P=0.04) in normal, but not tumour, DNA. No such association was observed between the GSTT1 genotype and the frequency of DNA alkylation or O(6)-MedG levels in patients with benign colon disease or rectal tumours. Patients with colon tumours or benign colon disease who were CYP2D6-poor metabolisers had higher ATase activity in normal tissue than patients who were CYP2D6 extensive metabolisers or CYP2D6 heterozygotes. Patients with the CYP2E1 Dra cd genotype were less likely to have a K-ras mutation: of 55 patients with the wild-type CYP2E1 genotype (dd), 23 had K-ras mutations, whereas none of the 7 individuals with cd genotype had a K-ras mutation (P=0.04). No other associations were observed between GSTT1, GSTM1, CYP2D6 and CYP2E1 Pst genotypes and adduct levels, ATase activity or mutational status. O(6)-MedG levels were not associated with ATase activity in either normal or tumour tissue. However, in 15 patients for whom both normal and tumour DNA contained detectable O(6)-MedG levels, there was a strong positive association between the normal DNA/tumour DNA adduct ratio and the normal tissue/tumour tissue ATase ratio (r(2)=0.66, P=0.001). These results indicate that host factors can affect levels both of the biologically effective dose arising from methylating agent exposure and of a susceptibility factor, the DNA repair phenotype.

Adenosine Triphosphatases↗
PubMed2001

Ethanol enhances the formation of endogenously and exogenously derived adducts in rat hepatic DNA.

To investigate the role of ethanol in chemically-induced carcinogenesis, we exposed Wistar rats to ethanol, either as an acute dose or for prolonged periods in a liquid diet and looked for effects on endogenously and exogenously derived DNA adducts. Changes in the cytochrome P450 protein (CYP 2E1) and its catalytic demethylase activity were also followed in order to provide a sequence of relatively well understood changes that are associated with free radical production and, therefore, potentially capable of affecting DNA. The exocyclic DNA adducts, ethenodeoxyadenosine (varepsilondA) and ethenodeoxycytidine (varepsilondC), known to arise from oxidative stress and lipid peroxidation (LPO) sources, were detected in the liver DNA of Wistar rats at background concentrations of 4-6 (varepsilondA) and 25-35 (varepsilondC) adducts per 10(9) parent bases. When rats were given either an acute dose of ethanol (5g/kg, i.g.) or exposed for 1 week to ethanol in a liquid diet (5%, w/v), etheno adduct levels were increased approximately 2-fold and this was statistically significant for varepsilondC (P<0.05 and P<0.02, respectively) for the two separate treatments.In N-nitrosodimethylamine (NDMA)-treated rats, acute ethanol treatment significantly increased the level of O(6)-methylguanine (O(6)-MeG) in hepatic DNA and this was paralleled by a decrease in O(6)-alkylguanine DNA alkyltransferase (ATase) activity; immunohistochemistry confirmed this increase of O(6)-MeG in both hepatic and renal nuclei. When rats were given ethanol in the diet and treated with NDMA, O(6)-MeG levels in hepatic DNA increased at 1 week which coincided with the peak of CYP 2E1-dependent NDMA-demethylase activity. Single cell gel electrophoresis of liver cells showed that after 1 week of exposure to ethanol, there was a small but significant increase in the frequency of DNA strand breaks induced by NDMA (P<0.05); after 4 weeks the increase was 1.4-fold (P<0.01). Our results indicate that exposures to ethanol, which resulted in blood ethanol concentrations similar to those seen in chronic alcoholics and increased levels of expression of the CYP 2E1 protein can exacerbate the DNA damaging effects of endogenous and exogenous alkylating agents. These observations provide indications of possible mechanisms for the carcinogenic or co-carcinogenic action of ethanol.

Alkylating Agents↗
PubMed2001

Physical inactivity and short-term all-cause mortality in adults with chronic disease.

OBJECTIVE: To ascertain the relationship of physical inactivity and short-term all-cause mortality in a prospective cohort of randomly selected managed care organization members aged 40 years and older who have multiple chronic diseases. METHODS: Clinical databases were used to identify all health plan members aged 40 years and older with 2 or more chronic health conditions (hypertension, coronary heart disease, diabetes mellitus, or dyslipemia) in 1994. A random sample of 2336 members was surveyed by mail and telephone interview regarding their health-related behaviors. Survey data were linked to mortality data from the 1995 to 1997 Minnesota Death Index. Cox proportional hazards regression was used to ascertain the association between physical inactivity and subsequent all-cause mortality, adjusting for potential confounders. RESULTS: Members who reported less than 30 minutes a week of physical activity at baseline had a subsequent mortality risk ratio of 2.82 (P<.001) vs those with 30 or more minutes of physical activity a week. Increased mortality risk persisted (mortality risk ratio, 2.15; P<.001) after adjustments for age, sex, current smoking, functional impairment, and comorbidity score. CONCLUSIONS: In adults with chronic diseases, the physically inactive had higher observed mortality within a 42-month period. If physical inactivity reflects an independent mortality risk, efforts to maintain physical activity in such patients may yield significant clinical benefits within a short period. By contrast, if inactivity is primarily a proxy for other factors that elevate mortality risks, a simple physician inquiry regarding inactivity may help to identify patients at risk of death.

Adult↗