Resistance profiles and adherence at primary virological failure in three different highly active antiretroviral therapy regimens: analysis of failure rates in a randomized study

OBJECTIVES

To investigate the interplay between resistance and adherence in the virological failure of three fundamentally different highly active antiretroviral therapy (HAART) regimens.

METHODS

We retrospectively identified 56 verified primary virological failures (viral load >400 HIV-1 RNA copies/mL) among 293 patients randomized to two nucleoside reverse transcriptase inhibitors (NRTIs)+ritonavir+saquinavir (RS-arm) (n=115), two NRTIs+nevirapine+nelfinavir (NN-arm) (n=118), or abacavir+stavudine+didanosine (ASD-arm) (n=60) followed up for a median of 90 weeks. Data on adherence were collected from patient files, and genotyping was performed on plasma samples collected at time of failure.

RESULTS

Treatment interruption or poor adherence was mainly caused by side effects and accounted for 74% of failures, and was associated with absence of resistance mutations. In the 30 failing patients not switched from randomized treatment, we found resistance in two of 12 patients in the RS-arm (M184 V only), four of six patients in the NN-arm [all four had non-nucleoside reverse transcriptase inhibitor (NNRTI) mutations], and seven of 12 patients in the ASD-arm (NRTI mutations only). Two adherent patients on randomized treatment failed in the RS-arm, none in the NN-arm, and six in the ASD-arm.

CONCLUSIONS

Primary virological failure was caused mainly by treatment interruption. No primary protease inhibitor (PI) mutations were found in patients failing on boosted saquinavir, whereas resistance to NNRTIs and NRTIs was prevalent in several patients failing on regimens based on these medications.

The plasma level of soluble urokinase receptor is elevated in patients with Streptococcus pneumoniae bacteraemia and predicts mortality

This multicentre prospective study was conducted to investigate whether the level of the soluble form of urokinase-type plasminogen activator receptor (suPAR) is elevated during pneumococcal bacteraemia and is of predictive value in the early stage of the disease. Plasma levels of suPAR were increased significantly (median 5.5; range 2.4-21.0 ng/mL) in 141 patients with pneumococcal bacteraemia, compared to 31 healthy controls (median 2.6, range 1.5-4.0 ng/mL, p 0.001). Furthermore, suPAR levels were elevated significantly in patients who died from the infection (n = 24) compared to survivors (n = 117; p < 0.001). No correlation was found between suPAR levels and C-reactive protein. In univariate logistic regression analysis, hypotension, renal failure, cerebral symptoms and high serum concentrations of protein YKL-40 and suPAR were associated significantly with mortality (p < 0.05). In multivariate analysis, only suPAR remained a significant predictor of death (mortality rate of 13 for suPAR levels of > 10 ng/mL; 95% CI: 1.1-158). The increase in suPAR levels may reflect increased expression by vascular or inflammatory cells in the setting of pneumococcal sepsis. This plasma protein may be used to identify patients who are severely ill with pneumococcal bacteraemia.

N-terminal proBNP and mortality in hospitalised patients with heart failure and preserved vs. reduced systolic function: data from the prospective Copenhagen Hospital Heart Failure Study (CHHF)

Preserved systolic function among heart failure patients is a common finding, a fact that has only recently been fully appreciated. The aim of the present study was to examine the value of NT-proBNP to predict mortality in relation to established risk factors among consecutively hospitalised heart failure patients and secondly to characterise patients in relation to preserved and reduced systolic function.

MATERIAL

At the time of admission 2230 consecutively hospitalised patients had their cardiac status evaluated through determinations of NT-proBNP, echocardiography, clinical examination and medical history. Follow-up was performed 1 year later in all patients.

RESULTS

161 patients fulfilled strict diagnostic criteria for heart failure (HF). In this subgroup of patients 1-year mortality was approximately 30% and significantly higher as compared to the remaining non-heart failure population (approx. 16%). Using univariate analysis left ventricular ejection fraction (LVEF), New York Heart Association classification (NYHA) and plasma levels of NT-proBNP all predicted mortality independently. However, regardless of systolic function, age and NYHA class, risk-stratification was provided by measurements of NT-proBNP. Having measured plasma levels of NT-proBNP, LVEF did not provide any additional prognostic information on mortality among heart failure patients (multivariate analysis).

CONCLUSION

The results show that independent of LVEF, measurements of NT-proBNP add additional prognostic information. It is concluded that NT-proBNP is a strong predictor of 1-year mortality in consecutively hospitalised patients with heart failure with preserved as well as reduced systolic function.

Assessment of heart involvement

Cardiac involvement frequently occurs in systemic sclerosis (SSc), contributing to the occurrence of symptoms, namely dyspnoea, fatigue, palpitations, and in some instances to the clinical evolution and prognosis of the disease. A thorough baseline screening of heart functioning and appropriate follow-up monitoring is therefore mandatory in all SSc patients. This consists of various simple, non-invasive ambulatory diagnostic procedures (visit, electrocardiogram, chest X-ray, Doppler-bidimensional echocardiogram), which provide information on the presence of rhythm and conduction disturbances, cardiac morphology and function, as well as on the possible presence of pulmonary hypertension (PH). When needed, added tests may be carried out, including long-term ambulatory electrocardiographic recording, assessment of cardiopulmonary performance by the six-minute walking test or cardiopulmonary stress test, cardiac catheterization (mandatory to confirm and better estimate PH), cardiac magnetic resonance imaging, and nuclear studies of myocardial function and perfusion.

European Scleroderma Study Group to define disease activity criteria for systemic sclerosis. III. Assessment of the construct validity of the preliminary activity criteria

OBJECTIVE

To further assess the construct validity of the three European Scleroderma Study Group (EScSG) preliminary activity indices for systemic sclerosis (SSc): for SSc as a whole, for diffuse SSc (dcSSc), and for limited SSc (lcSSc).

METHODS

30/290 SSc clinical charts collected for the EScSG study used to develop activity criteria for SSc were selected and sent to four clinical experts in SSc. The experts ranked the charts from 1 to 30 (1=lowest activity, 30=highest activity). The relationships among the ranks given by each investigator and each of the three scores, and between any two of the ranks were investigated.

RESULTS

A consistently significant correlation (r(s)=0.530-0.712) was found between the ranks given by each of the four investigators and the index for the entire patient group. A similar level of agreement was detected between each couple of the four experts (r(s)=0.428-0.720). Moreover, the ranks given in patients with an index >3 were significantly higher than those given for patients with an index < or =3. This cut off point had previously been shown to best discriminate patients with active disease.

CONCLUSIONS

Of the originally developed activity indexes, the whole series index has been externally validated. The index comprises the first preliminary, but necessary, groundwork to improve the concept of disease activity in SSc, which is still ill defined. It can be used as a preliminary activity index in clinical investigational studies.

NT-proBNP: a new diagnostic screening tool to differentiate between patients with normal and reduced left ventricular systolic function

OBJECTIVE

To evaluate whether measurements of N-terminal pro-brain natriuretic peptide (NT-proBNP) can be used to differentiate patients with normal and reduced left ventricular ejection fraction (LVEF) in an unselected consecutive group of hospital inpatients.

SETTING

City general hospital, Copenhagen, Denmark.

PATIENTS AND DESIGN

During a 10 month period 2230 admissions to a city general hospital (80% of targeted patients) had an echocardiographic evaluation of left ventricular function, a comprehensive clinical evaluation, and blood analysis of N-terminal-pro-brain natriuretic peptide (NT-proBNP) within 24 hours of admission. Exclusions resulted from lack of informed consent or failure to obtain the required evaluations before death or discharge from hospital. Echocardiography was unsatisfactory in 37 patients, so the final number studied was 2193.

RESULTS

A raised NT-proBNP (>or= 357 pmol/l) identified patients with an LVEF of <or= 40% (n = 157) with a sensitivity of 73% and a specificity of 82%. The negative predictive value of having an NT-proBNP concentration below 357 pmol/l was 98%. Concentrations of NT-proBNP increased with increasing age and with decreasing LVEF (p < 0.05). A predicted concentration of NT-proBNP (corrected for age, sex, and serum creatinine) was determined for each patient. In patients with an NT-proBNP value less than predicted, the probability of having an LVEF of > 40% was more than 97%. This probability rapidly decreased to 70% as the measured NT-proBNP increased to 150% of the predicted value.

CONCLUSIONS

A single measurement of NT-proBNP at the time of hospital admission provides important information about LVEF in unselected patients.

Clinical lipoatrophy in HIV-1 patients on HAART is not associated with increased abdominal girth, hyperlipidaemia or glucose intolerance

OBJECTIVE

To compare information on body fat changes from questionnaire and clinical examination and to study lipoatrophy in HIV-1 patients on highly active antiretroviral therapy (HAART).

METHODS

The study was cross-sectional within a randomized trial. One hundred and sixty-eight male HIV-1 patients were examined by questionnaire and clinical examination. Clinical lipoatrophy was studied and defined as fat wasting in the face, legs and/or arms. Fasting blood samples reflecting lipid and glucose metabolism were taken and the role of indinavir, ritonavir (RTV) and RTV/saquinavir (SQV) on lipoatrophy was investigated.

RESULTS

After a median of 17 months on HAART, concordance rates between information on changes in body fat from questionnaire and clinical examination were significant and varied from 70 to 96%. With a positive criteria of lipoatrophy in both assessments, 14% of patients had lipoatrophy. These patients had lower weight (P = 0.0007), weight loss from baseline (P = 0.003), lower circumferences at all measurements (P < 0.01), lower plasma triglycerides and low-density lipoprotein (LDL) (P < 0.05) and longer treatment with stavudine (P = 0.0009). Homeostasis model assessment (HOMA) estimates for insulin resistance and beta-cell function were comparable. Plasma cholesterol, triglycerides and very low-density lipoprotein (VLDL) were higher in patients receiving RTV or RTV/SQV (P < 0.03).

CONCLUSION

Questionnaire and clinical assessment provide concordant information on changes in body fat. Lipoatrophic patients on HAART with neither increase in abdominal circumference, nor hyperlipidaemia nor glucose intolerance may have side-effects to protease inhibitor treatment, to nucleoside reverse transcriptase inhibitor treatment (stavudine) or suffer from a drug-independent condition.

Additive effects of Helicobacter pylori lipopolysaccharide and proteins in monocyte inflammatory responses

BACKGROUND

Chronic active gastritis associated with Helicobacter pylori infection is characterized by both a neutrophil and a mononuclear leukocyte infiltrate. While neutrophil functions in relation to H. pylori are well described, the interactions between Helicobacter bacterial factors and monocytes are poorly understood in relation to the mucosal inflammatory process.

METHODS

Sonicates of a clinical strain as well as of a type strain of H. pylori were prepared in vitro. Monocytes from healthy donors were induced to release L-selectin (CD62L), to upregulate the adherence molecules (CD11a, CD11b. CD11c) and to produce toxic oxygen radicals. The inducing activities were assessed by flow cytometry and chemiluminescence.

RESULTS

A dose-dependent shedding of CD62L and upregulation of CD11b and CD11c were observed with both bacterial strains as well as PMA and fMLP. CD11a remained unchanged. Activity could be attributed to bacterial factors of both lipopolysaccharide (LPS) and protein characteristics. The alterations observed for CD11b, CD11c and CD62L were induced by the same protein fractions in parallel. suggesting a common component and mechanism of action. A major protein component was urease, although other minor protein bands were found as well. Monoclonal antibodies to CD14-inhibited monocyte inflammatory responses induced by H. pylori sonicate at low concentration, whereas further LPS pierce-matrix reduction was necessary at high sonicate concentrations to reduce monocyte-inducing activity.

CONCLUSIONS

Monocyte inflammatory activation is induced by H. pylori sonicate components. Factors of both LPS and protein characteristics are involved and an additive effect was demonstrated. Urease appears to be a major component in the protein preparations of highest inducing capacity. Further studies are warranted to assess whether the monocyte activation properties described here are related to the diversity of clinical gastroduodenal outcome for the chronic type B gastritis associated with H. pylori infection.

Prediction of human protein function from post-translational modifications and localization features

We have developed an entirely sequence-based method that identifies and integrates relevant features that can be used to assign proteins of unknown function to functional classes, and enzyme categories for enzymes. We show that strategies for the elucidation of protein function may benefit from a number of functional attributes that are more directly related to the linear sequence of amino acids, and hence easier to predict, than protein structure. These attributes include features associated with post-translational modifications and protein sorting, but also much simpler aspects such as the length, isoelectric point and composition of the polypeptide chain.

HIV-1 subtypes in Denmark

The objective of this study was to investigate the presence of non-subtype B HIV-1 in Denmark. The C2-V3-C3 region of the env gene from proviral DNA obtained from patients suspected of being infected with non-subtype B virus was PCR-amplified and directly sequenced. The DNA sequences were aligned with full-length HIV-1 reference strains from each subtype and analysed using the phylogenetic package PHYLIP 3.1. The neighbour-joining method was used with 100 bootstraps. Of the 144 patients included in this study C2-V3-C3 sequences were obtained from 129 patients (90%). The phylogenetic analyses showed that virus from 49 patients (38%) was subtype A, 39 (30%) subtype C, 9 (7%) subtype D, 14 (11%) subtype CRF01_AE, 16 (12%) subtype B, 1 (1%) subtype F and 1 (1%) subtype J. This study demonstrates that almost all subtypes can be detected in Denmark; all non-subtype B infections could be traced to countries with a high prevalence of non-subtype B virus.

MRI of the arthritic small joints: comparison of extremity MRI (0.2 T) vs high-field MRI (1.5 T)

The aim of this study was to compare the diagnostic capabilities of extremity MRI (E-MRI) with high-field MRI in arthritic small joints, and to evaluate the patients' acceptance and perceptions of the two MR systems. One hundred three patients (group 1 = 28 patients with RA < 3 years, group 2 = 25 patients with reactive and psoriatic arthritis and mixed connective tissue disease, group 3 = 25 patients with rheumatoid arthritis (RA) more than 3 years and group 4 = 25 patients with arthralgia) underwent dedicated E-MRI and high-field MRI of the wrist and finger joints. Coronal short tau inversion recovery and transversal 3D T1-weighted images before and after gadodiamide (Gd) were performed in both cases to outline the volume of the synovial membrane (Vsm) and to evaluate joints with enhancement, effusion, bone edema, and erosions. Investigators blinded to the clinical findings evaluated the images. Patients' compliance and acceptance of E-MRI and high-field MRI were evaluated. The median Vsm obtained on E-MRI did not differ significantly from that obtained on high-field MRI. Vsm = 1 ml (E-MRI) and 1.1 ml (high-field MRI) before Gd and Vsm = 0.1 ml (E-MRI) and 0 ml (high-field MRI) after Gd (Wilcoxon test, p > 0.05). The difference in agreement was 8% for joint enhancement, 2% for joint effusion, 3% for bone edema, and 4% for bone erosions. Of the patients, 64% preferred E-MRI due to more comfortable positioning and less claustrophobia and noise. Extremity MRI of the small arthritic joints is comparable to high-field MRI and more readily accepted than high-field MRI by this patient group.

Preoperative routine magnetic resonance cholangiopancreatography before laparoscopic cholecystectomy: A prospective study

OBJECTIVES

To assess the diagnostic value of magnetic resonance cholangiopancreatography (MRCP) in detecting common bile duct stones in the preoperative investigation of patients electively referred for gallstone disease, to find out the incidence of asymptomatic common duct stones, and to correlate clinical symptoms and history and liver function tests (LFT) with the actual occurrence of common duct stones.

DESIGN

Prospective study.

SETTING

General hospital, Denmark.

PATIENTS

180 consecutive non-jaundiced patients referred with symptomatic gallstones for elective cholecystectomy.

INTERVENTIONS

LFT, abdominal ultrasonography, MRCP, endoscopic retrograde cholangiopancreatography (ERCP), questionnaire.

MAIN OUTCOME MEASURES

Positive and negative predictive values and accuracy of MRCP, number of patients with asymptomatic stones, and correlation of symptoms with the presence of stones.

RESULTS

26/180 patients had common duct stones (14%). Only one (<1%) had an asymptomatic stone. For detection of such stones, MRCP's positive predictive value was 0.95 (95% confidence interval (CI): 0.86 to 1.00), negative predictive value 0.96 (0.93 to 0.99), and accuracy 0.85 (0.93 to 0.99). MRCP missed 5 stones 1-4 mm in size in 5 patients; 17/64 patients with raised LFTs had stones (27%). The probability of stones was highest when the patients had both raised LFTs and a dilated common (>7 mm) bile duct (82%). There were no readmissions with ductal stones in the 6-month postoperative period.

CONCLUSIONS

The predicive values of MRCP were fairly good, but MRCP misses some small stones <5 mm in size. Asymptomatic stones in the common duct are not common in this population and should not be screened for. The probability of stones increases with the number of predictive factors. Patients should be questioned carefully about signs of biliary obstruction, and only be offered preoperative MRCP should they have a suspicious history, raised LFTs, or a dilated common duct.

Fetuin and fetuin messenger RNA in granulosa cells of the rat ovary

The hardening reaction that occurs in the zona pellucida to block polyspermy can be overcome in oocyte cultures in the presence of fetal serum or the serum component fetuin. Fetuin may also prevent precocious zona hardening by inhibiting a ZP2 proteinase released spontaneously by cortical granules during maturation of the oocyte. We demonstrated fetuin mRNA in the rat ovary by reverse transcriptase-polymerase chain reaction and localized it by in situ hybridization. Fetuin mRNA was present in all granulosa cells of growing and large follicles. Immunohistochemical analysis revealed that the fetuin protein was only present in some of the small, growing follicles. In large, healthy follicles, fetuin protein was confined to cumulus cells and granulosa cells bordering the antrum. Fetuin was present in atretic follicles, but the staining pattern differed from that of healthy follicles. The follicular antrum contained a substantial amount of fetuin, but whether granulosa cells secreted it or it originated in the ovarian blood supply could not be confirmed. We concluded that at least a portion of the fetuin is produced by granulosa cells of growing and large follicles, suggesting that fetuin may function in a paracrine manner to maintain the zona pellucida in a penetrable state for fertilization.

Effect of secondary structure on the thermodynamics and kinetics of PNA hybridization to DNA hairpins

The binding of a series of PNA and DNA probes to a group of unusually stable DNA hairpins of the tetraloop motif has been observed using absorbance hypochromicity (ABS), circular dichroism (CD), and a colorimetric assay for PNA/DNA duplex detection. These results indicate that both stable PNA-DNA and DNA-DNA duplexes can be formed with these target hairpins, even when the melting temperatures for the resulting duplexes are up to 50 degrees C lower than that of the hairpin target. Both hairpin/single-stranded and hairpin/hairpin interactions are considered in the scope of these studies. Secondary structures in both target and probe molecules are shown to depress the melting temperatures and free energies of the probe-target duplexes. Kinetic analysis of hybridization yields reaction rates that are up to 160-fold slower than hybridization between two unstructured strands. The thermodynamic and kinetic obstacles to hybridization imposed by both target and probe secondary structure are significant concerns for the continued development of antisense agents and especially diagnostic probes.

The tumor-infiltrating B cell response in medullary breast cancer is oligoclonal and directed against the autoantigen actin exposed on the surface of apoptotic cancer cells

Medullary carcinoma of the breast (MCB) is a morphologically and biologically distinct subtype of human breast cancer that, despite cytologically anaplastic features, has a more favorable prognosis than other types of breast cancer at similar stages of differentiation. It has been proposed that the improved clinical outcome is due, at least in part, to the presence of a prominent lymphoplasmacytic cell infiltrate in the tumor stroma. We studied the B lymphoplasmacytic cell infiltrates in MCB to determine the role of the antibody response produced by the local infiltrating cells. Oligoclonal predominance among tumor-infiltrating B cells in a panel of MCB patients was observed, suggesting that certain B cell clones were expanded, possibly in response to specific tumor-associated stimuli. IgG antibody phage-display libraries were generated from MCB-infiltrating lymphoplasmacytic cells of two patients, and MCB-reactive monoclonal antibodies were retrieved by selection on fresh-frozen MCB tissue sections. Analysis by mass spectrometry revealed that the antigen targeted by the dominant clones in the oligoclonal B lymphoplasmacytic response in both patients was not a cancer-specific antigen but the cytoskeletal protein beta-actin. MCB exhibits an increased rate of apoptosis, and apoptotic MCB cells were shown to expose actin on the cell surface, permitting its recognition by the humoral immune system. Further, actin fragments, similar to those observed after cleavage with the apoptotic protease granzyme B, were observed in MCB tissue. Our results indicate that the major antibody response produced by tumor-infiltrating B lymphoplasmacytic cells are autoimmune in nature and a consequence of the perturbed state of increased MCB apoptosis caused by granzyme B-induced T cell cytotoxicity and/or intrinsic cellular factors of MCB cells.

Magnetic resonance imaging of the wrist and finger joints in patients with inflammatory joint diseases

OBJECTIVE

To study magnetic resonance imaging (MRI) features in the wrist and metacarpophalangeal (MCP), proximal interphalangeal (PIP), and distal interphalangeal (DIP) joints in 4 patient groups: early rheumatoid arthritis (RA) (< 3 yrs); established RA (> 3 yrs); other arthritis; arthralgia.

METHODS

MRI was obtained before and after contrast (gadodiamide) injection of the wrist and finger joints in 103 patients and 7 controls. The study included: (1) 28 patients with disease duration < 3 yrs who fulfilled the American College of Rheumatology (ACR) criteria for RA; (2) 25 patients with RA disease duration > 3 yrs who fulfilled the ACR criteria. (3) 25 patients with reactive arthritis, psoriatic arthritis, or mixed connective tissue disease; and (4) 25 patients with arthralgia. The following MRI variables were assessed: number of joints with enhancement after contrast injection, number of joints with joint fluid, and number of bones with edema in the wrist and fingers. The volume of the enhancing synovial membrane after contrast injection in the MCP, PIP, and DIP joints was manually outlined. MR images were scored independently under blinded conditions.

RESULTS

Bone marrow edema was found in 68% of the patients with established RA, and the number of bones with edema was significantly higher in patients with established RA compared to patients with early RA, other arthritis, and arthralgia (Mann-Whitney p < 0.04). Bone edema was not found in patients with arthralgia. There was marked overlap within and between the patient groups. No differences in MRI features were found between patients with early RA and patients with other arthritis. The volumes of the synovial membrane in the MCP, PIP, and DIP joints were significantly higher in patients with arthritis compared to patients with arthralgia.

CONCLUSION

Although there was marked overlap between the arthritis patient groups, MRI determined bone marrow edema and synovial membrane volumes provided additional information about disease activity and may be used as a marker of it. Bone marrow edema appeared with the highest percentage in patients with long duration of RA (> 3 yrs) and is probably secondary to changes in inflammatory activity.

Family-based transmission disequilibrium test (TDT) and case-control association studies reveal surfactant protein A (SP-A) susceptibility alleles for respiratory distress syndrome (RDS) and possible race differences

A key cause of respiratory distress syndrome (RDS) in the prematurely born infant is deficiency of pulmonary surfactant, a lipoprotein complex. Both low levels of surfactant protein A (SP-A) and SP-A alleles have been associated with RDS. Using the candidate gene approach, we performed family-based linkage studies to discern linkage of SP-A to RDS and identify SP-A susceptibility or protective alleles. Moreover, we performed case-control studies of whites and blacks to detect association between RDS and SP-A alleles. Transmission disequilibrium test (TDT) analysis revealed that the frequency of transmission (from parent to the offspring with RDS) of alleles 6A(2) and 1A(0) and of 1A(0)/6A(2) haplotype in RDS was increased, whereas transmission of alleles 1A(5) and 6A(4) and of haplotype 1A(5)/6A(4) was decreased. Extended TDT analysis further strengthened the observations made. The case-control studies showed that in whites or blacks with RDS the frequencies of specific genotypes, 1A(0) and 6A(2) or 1A(0), were increased, respectively, but the frequency of specific 6A(3) genotypes was increased in certain white subgroups and decreased in blacks. Regression analysis revealed gestational age (GA) and 6A(3) genotypes are significant factors in blacks with RDS. In whites with RDS, GA and antenatal steroids are important factors. The data together indicate linkage between SP-A and RDS; certain SP-A alleles/haplotypes are susceptibility (1A(0), 6A(2), 1A(0)/6A(2)) or protective (1A(5), 6A(4), 1A(5)/6A(4)) factors for RDS. Some differences between blacks and whites with regard to SP-A alleles may exist.

The Virtual Brain Project--development of a neurosurgical simulator

As a joined project between Aalborg University and Aalborg Hospital Denmark, a neuro-surgical simulator is being developed. In this paper the objective of the project is outlined and an overview of the research activities within the project is given. Focus is on 3D modelling of the brain, deformable models and the development of two demonstrators, including one for training of punctuation of ventricle using visual and haptic feedback.

European multicentre study to define disease activity criteria for systemic sclerosis. II. Identification of disease activity variables and development of preliminary activity indexes

OBJECTIVE

To develop criteria for disease activity in systemic sclerosis (SSc) that are valid, reliable, and easy to use.

METHODS

Investigators from 19 European centres completed a standardised clinical chart for a consecutive number of patients with SSc. Three protocol management members blindly evaluated each chart and assigned a disease activity score on a semiquantitative scale of 0-10. Two of them, in addition, gave a blinded, qualitative evaluation of disease activity ("inactive to moderately active" or "active to very active" disease). Both these evaluations were found to be reliable. A final disease activity score and qualitative evaluation of disease activity were arrived at by consensus for each patient; the former represented the gold standard for subsequent analyses. The correlations between individual items in the chart and this gold standard were then analysed.

RESULTS

A total of 290 patients with SSc (117 with diffuse SSc (dSSc) and 173 with limited SSc (lSSc)) were enrolled in the study. The items (including Delta-factors-that is, worsening according to the patient report) that were found to correlate with the gold standard on multiple regression were used to construct three separate 10-point indices of disease activity: (a) Delta-cardiopulmonary (4.0), Delta-skin (3.0), Delta-vascular (2.0), and Delta-articular/muscular (1.0) for patients with dSSc; (b) Delta-skin (2.5), erythrocyte sedimentation rate (ESR) >30 mm/1st h (2.5), Delta-cardiopulmonary (1.5), Delta-vascular (1.0), arthritis (1.0), hypocomplementaemia (1.0), and scleredema (0.5) for lSSc; (c) Delta-cardiopulmonary (2.0), Delta-skin (2.0), ESR >30 mm/1st h (1.5), total skin score >20 (1.0), hypocomplementaemia (1.0), scleredema (0.5), digital necrosis (0.5), Delta-vascular (0.5), arthritis (0.5), TLCO <80% (0.5) for all patients with SSc. The three indexes were validated by the jackknife technique. Finally, receiver operating characteristic curves were constructed in order to define the value of the index with the best discriminant capacity for "active to very active" patients.

CONCLUSIONS

Three feasible, reliable, and valid preliminary indices to define disease activity in SSc were constructed.