Proteomics to predict the response to tumour necrosis factor-α inhibitors in rheumatoid arthritis using a supervised cluster-analysis based protein score.

OBJECTIVE: In rheumatoid arthritis (RA), it is of major importance to identify non-responders to tumour necrosis factor-α inhibitors (TNFi) before starting treatment, to prevent a delay in effective treatment. We developed a protein score for the response to TNFi treatment in RA and investigated its predictive value. METHOD: In RA patients eligible for biological treatment included in the BiOCURA registry, 53 inflammatory proteins were measured using xMAP® technology. A supervised cluster analysis method, partial least squares (PLS), was used to select the best combination of proteins. Using logistic regression, a predictive model containing readily available clinical parameters was developed and the potential of this model with and without the protein score to predict European League Against Rheumatism (EULAR) response was assessed using the area under the receiving operating characteristics curve (AUC-ROC) and the net reclassification index (NRI). RESULTS: For the development step (n = 65 patient), PLS revealed 12 important proteins: CCL3 (macrophage inflammatory protein, MIP1a), CCL17 (thymus and activation-regulated chemokine), CCL19 (MIP3b), CCL22 (macrophage-derived chemokine), interleukin-4 (IL-4), IL-6, IL-7, IL-15, soluble cluster of differentiation 14 (sCD14), sCD74 (macrophage migration inhibitory factor), soluble IL-1 receptor I, and soluble tumour necrosis factor receptor II. The protein score scarcely improved the AUC-ROC (0.72 to 0.77) and the ability to improve classification and reclassification (NRI = 0.05). In validation (n = 185), the model including protein score did not improve the AUC-ROC (0.71 to 0.67) or the reclassification (NRI = -0.11). CONCLUSION: No proteomic predictors were identified that were more suitable than clinical parameters in distinguishing TNFi non-responders from responders before the start of treatment. As the results of previous studies and this study are disparate, we currently have no proteomic predictors for the response to TNFi.

Screening for thyroid dysfunction and diabetes in patients with carpal tunnel syndrome.

BACKGROUND: Current literature demonstrates that patients with carpal tunnel syndrome (CTS) have a higher prevalence of hypothyroidism and diabetes. The British Society for Surgery of the Hand (BSSH) advises screening CTS patients for thyroid and glucose dysfunction before surgery. This study aimed to analyze the current departmental practice for patients listed for carpal tunnel decompression (CTD) with respect to preoperative assessment of diabetic and thyroid status. METHOD: A retrospective review of all patients who underwent surgery for CTS under one team over a 3 year period (2009-2011) in a UK teaching hospital was performed. Patients' medical records and pathology results were reviewed. RESULTS: A total of 103 procedures were performed in 100 patients. Preoperative thyroid function was checked in 63/100 patients with an abnormal result in 3/63 patients. Two of these patients were subsequently diagnosed with hypothyroidism. Similarly blood glucose was checked in 67/100 patients. This resulted in the new diagnosis of three patients with diabetes. CONCLUSION: The results are consistent with the view that CTS is associated with thyroid dysfunction and diabetes and screening helps in diagnosing new cases of these conditions in this select group. The cost of diagnosing new cases of hypothyroidism and diabetes can be considered as money well spent.

Angiogenic factors and the lectin pathway of complement in women with secondary recurrent pregnancy loss.

The poor remodeling of placental spiral arteries seen in preeclampsia is also discussed to contribute to recurrent pregnancy loss (RPL) preceded by abnormal angiogenesis and excessive complement activation. Low levels of Mannose-binding-lectin (MBL), a pattern recognition molecule (PRM) of the lectin pathway, have been found in women with RPL. We propose that pregnancy loss is connected to defective angiogenesis with reperfusion damage in the placenta and decreased levels of PRM in the lectin pathway in women with RPL. In this cohort study, we investigate the angiogenic factors and the lectin complement pathway in early pregnancy and their time-dependent relationship with pregnancy outcomes in 76 women with secondary RPL (sRPL) who have at least four prior pregnancy losses and a live birth. We evaluated levels of Angiopoietin-1 (Ang-1), Angiopoietin-2 (Ang-2), Vascular Endothelial Growth Factor (VEGF), soluble fms-like tyrosine kinase-1 (sFlt-1), and the PRMs, MBL, ficolin-1, -2, -3 and an additional soluble PRM, Pentraxin-3, during the 5th, 6th, and 7th gestational weeks. Our results showed that, compared to live births, pregnancies that ended in loss were associated with elevated VEGF levels and decreased levels of the Ang-2/Ang-1 ratio. Also, increasing levels of ficolin-2 were significantly associated with pregnancy loss, with MBL showing no association. Our research suggests that women with sRPL may have inadequate placentation with impaired angiogenesis in pregnancies ending in a loss.

Systemic inflammation in childhood obesity: circulating inflammatory mediators and activated CD14++ monocytes.

AIMS/HYPOTHESIS: In adults, circulating inflammatory mediators and activated CD14(++) monocytes link obesity to its metabolic and cardiovascular complications. However, it is largely unknown whether these inflammatory changes already occur in childhood obesity. To survey inflammatory changes during the early stages of obesity, we performed a comprehensive analysis of circulating inflammatory mediators, monocyte populations and their function in childhood obesity. METHODS: In lean and obese children aged 6 to 16 years (n = 96), 35 circulating inflammatory mediators including adipokines were measured. Hierarchical cluster analysis of the inflammatory mediator profiles was performed to investigate associations between inflammatory mediator clusters and clinical variables. Whole-blood monocyte phenotyping and functional testing with the toll-like receptor 4 ligand, lipopolysaccharide, were also executed. RESULTS: First, next to leptin, the circulating mediators chemerin, tissue inhibitor of metalloproteinase 1, EGF and TNF receptor 2 were identified as novel inflammatory mediators that are increased in childhood obesity. Second, cluster analysis of the circulating mediators distinguished two obesity clusters, two leanness clusters and one mixed cluster. All clusters showed distinct inflammatory mediator profiles, together with differences in insulin sensitivity and other clinical variables. Third, childhood obesity was associated with increased CD14(++) monocyte numbers and an activated phenotype of the CD14(++) monocyte subsets. CONCLUSIONS/INTERPRETATION: Inflammatory mediator clusters were associated with insulin resistance in obese and lean children. The activation of CD14(++) monocyte subsets, which is associated with increased development of atherosclerosis in obese adults, was also readily detected in obese children. Our results indicate that inflammatory mechanisms linking obesity to its metabolic and cardiovascular complications are already activated in childhood obesity.

Treatment-specific changes in circulating adipocytokines: a comparison between tumour necrosis factor blockade and glucocorticoid treatment for rheumatoid arthritis.

OBJECTIVE: There is increasing evidence that adipocytokines may exert proinflammatory and destructive effects in rheumatoid arthritis (RA). Hence, the authors investigated the relationship between adipocytokines and several features associated with RA (inflammation, joint destruction and cardiovascular disease), as well as the effect of treatment with a tumour necrosis factor inhibitor or glucocorticoids (GCs) hereupon. METHODS: Serum levels of adiponectin, leptin, resistin, visfatin, vaspin and lipids were determined in a well-defined cohort of patients with RA before and after 16 weeks of adalimumab treatment (adalimumab cohort). The same parameters were analysed in two other cohorts of patients with RA before and after 2 weeks of high-dose prednisolone (high GC cohort) and before and after 22 weeks of treatment with a combination regimen with tapered high-dose prednisolone (COBRA -GC cohort). Radiographs of hands and feet (adalimumab and COBRA-GC cohorts) were assessed at baseline and after treatment. RESULTS: Treatment with adalimumab or GC showed opposing effects on vaspin and visfatin levels. Lipid levels improved after several months of adalimumab or GC treatment; in the adalimumab cohort, this was related to reduced visfatin levels, independent of C reactive protein levels. After long-term adalimumab or GC treatment, resistin levels declined, which was associated with a decrease in inflammation markers. In the adalimumab cohort, baseline resistin levels were predictive of baseline radiological damage, independent of anticitrullinated peptide antibodies status or C reactive protein levels. CONCLUSION: Changes in serum adipocytokine levels were treatment specific, further strengthening the role of visfatin and resistin in several disease manifestations of RA.

Recognition of heat shock protein 60 epitopes in children with type 1 diabetes.

BACKGROUND: Treatment with a specific HSP60 epitope in new onset of type 1 diabetes (T1D) patients has been shown to preserve endogenous insulin production. Previously, recognition of pan HLA-DR-binding HSP60 epitopes in various autoimmune diseases was found; this study investigated recognition of these epitopes in newly diagnosed T1D patients and correlated findings to the occurrence of a partial remission. METHODS: Peripheral blood mononuclear cells of 18 children with T1D were prospectively collected at disease onset and a few months after diagnosis. Epitope-specific T-cell proliferation and cytokine production (intracellular and in culture supernatants) were measured. Results were compared with 31 longstanding T1D patients and ten healthy controls. RESULTS: Although HSP60 epitope-specific T-cell proliferative responses were detected, overall proliferative responses were low. At onset, epitope-specific intracellular IFN-γ production was higher in T1D patients compared with healthy controls (p < 0.05). At follow-up, both IL-10 and IFN-γ production were higher in those without a partial remission than in those with a partial remission (both p < 0.05). Also, IL-10 and IFN-γ production were higher compared with onset for patients without a PR (both p < 0.01). In supernatants of HSP60 epitope-specific T-cell cultures, no substantial differences in cytokine production were found between T1D patients with and without a partial remission, either at onset or a few months after onset. As patient numbers were small, results should be interpreted with caution. CONCLUSIONS: Pan-DR-binding HSP60 peptides induced low peptide-specific proliferative responses and peptide-specific production of some, mainly intracellular, cytokines in T1D patients. Recognition did not differ significantly between patient groups and various time points.

Local atherosclerotic plaques are a source of prognostic biomarkers for adverse cardiovascular events.

OBJECTIVE: Atherosclerotic cardiovascular disease is a major burden to health care. Because atherosclerosis is considered a systemic disease, we hypothesized that one single atherosclerotic plaque contains ample molecular information that predicts future cardiovascular events in all vascular territories. METHODS AND RESULTS: AtheroExpress is a biobank collecting atherosclerotic lesions during surgery, with a 3-year follow-up. The composite primary outcome encompasses all cardiovascular events and interventions, eg, cardiovascular death, myocardial infarction, stroke, and endovascular interventions. A proteomics search identified osteopontin as a potential plaque biomarker. Patients undergoing carotid surgery (n=574) served as the cohort in which plaque osteopontin levels were examined in relation to their outcome during follow-up and was validated in a cohort of patients undergoing femoral endarterectomy (n=151). Comparing the highest quartile of carotid plaque osteopontin levels with quartile 1 showed a hazard ratio for the primary outcome of 3.8 (95% confidence interval, 2.6-5.9). The outcome did not change after adjustment for plaque characteristics and traditional risk factors (hazard ratio, 3.5; 95% confidence interval, 2.0-5.9). The femoral validation cohort showed a hazard ratio of 3.8 (95% confidence interval 2.0 to 7.4) comparing osteopontin levels in quartile 4 with quartile 1. CONCLUSIONS: Plaque osteopontin levels in single lesions are predictive for cardiovascular events in other vascular territories. Local atherosclerotic plaques are a source of prognostic biomarkers with a high predictive value for secondary manifestations of atherosclerotic disease.

Increased expression of interleukin-7 in labial salivary glands of patients with primary Sjögren's syndrome correlates with increased inflammation.

OBJECTIVE: To study the expression levels and immunostimulatory capacities of interleukin-7 (IL-7) in primary Sjögren's syndrome. METHODS: Labial salivary gland (LSG) IL-7 expression was determined by immunohistochemistry, using a quantitative scoring system, in 30 patients with sicca syndrome: 15 patients with primary Sjögren's syndrome (SS) and 15 patients with non-SS sicca syndrome. The correlation of IL-7 expression in LSGs with parameters of local and peripheral disease was studied, and serum and salivary IL-7 levels were determined. Additionally, the effects of IL-7 on cytokine production by peripheral blood mononuclear cells (PBMCs) from patients with primary SS were determined in vitro by Luminex multicytokine assay and compared with the effects in control subjects. RESULTS: The expression of IL-7 in LSGs was higher in patients with primary SS compared with that in patients with non-SS sicca syndrome. IL-7 was observed primarily in the vicinity of lymphocytic infiltrates. Salivary IL-7 levels in patients with primary SS were higher than those in control subjects. In all 30 patients with sicca syndrome, IL-7 expression in LSGs correlated with parameters of both local and peripheral disease. Furthermore, IL-7 stimulated T cell-attracting and T cell-differentiating cytokines (monokine induced by interferon-gamma [IFNgamma], IFNgamma-inducible 10-kd protein, IL-12, and IL-15), as well as Th1 (IFNgamma), Th2 (IL-4), Th17 (IL-17A), proinflammatory (tumor necrosis factor alpha and IL-1alpha), and regulatory (IL-10 and IL-13) cytokine production by PBMCs. All of these cytokines were previously shown to be associated with primary SS. The IL-7-induced increase in IL-10 production in patients with primary SS was reduced compared with that in control subjects. CONCLUSION: The correlation between LSG IL-7 expression and (local) disease parameters in primary SS as well as the IL-7-mediated induction of inflammatory cytokines indicate that IL-7 might contribute to the immunopathology of primary SS.

T-cell response to viral antigens in adults and children with common variable immunodeficiency and specific antibody deficiency.

Several T cell abnormalities have been described in common variable immunodeficiency (CVID), a B cell disorder of mainly unknown origin. A subset of CVID patients suffers from frequent reactivations of herpes viruses. We studied T cell function in CVID [and in a subset of paediatric patients with specific antibody deficiency (SAD)] by measuring T cell proliferation and cytokine production in response to herpes virus-antigens in paediatric CVID patients (n=9) and paediatric SAD patients (n=5), in adult CVID patients (n=14) and in healthy controls. Paediatric CVID patients, but not SAD patients, displayed moderately increased CD8+ T cell proliferation in response to cytomegalovirus, human herpes virus type 6B (HHV6-B) and herpes simplex virus compared to controls. CD8+ T cell responses in adult CVID patients tended to be increased in response to cytomegalovirus and herpes simplex virus. In response to stimulation with herpes virus antigens, the proinflammatory cytokines interleukin (IL)-1beta, IL-6, tumour necrosis factor (TNF)-alpha and interferon inducible protein (IP)-10 were produced. Overall, no major differences were detected in cytokine production upon stimulation between patients and controls, although higher IL-10 and IL-12 production was detected in paediatric patients. In conclusion, cellular immunity against herpes virus antigens appears undisturbed in CVID patients, although defects in subpopulations of CVID patients cannot be excluded.

CC chemokine ligand-5 (CCL5/RANTES) and CC chemokine ligand-18 (CCL18/PARC) are specific markers of refractory unstable angina pectoris and are transiently raised during severe ischemic symptoms.

BACKGROUND: Chemokines play an important role in atherogenesis and in ischemic injury and repair; however, prospective data on individual chemokines in unstable angina pectoris (UAP) are scarce. Therefore, we assessed chemokine patterns in a prospective cohort of patients with UAP. METHODS AND RESULTS: Plasma samples of 54 patients with Braunwald class IIIB UAP were examined at baseline for 11 chemokines and 5 inflammatory mediators via multiplex analysis. Levels of CC chemokine ligand (CCL)-5 (also known as RANTES [regulated on activation, normally T-cell expressed, and secreted]; 32.7 versus 23.1 ng/mL, P=0.018) and CCL18 (also known as PARC [pulmonary and activation-regulated chemokine]; 104.4 versus 53.7 ng/mL, P=0.011) were significantly elevated in patients with refractory ischemic symptoms versus stabilized patients. Temporal monitoring by ELISA of CCL5, CCL18, and soluble CD40 ligand (sCD40) levels revealed a drop in CCL5 and sCD40L levels in all UAP patients from day 2 onward (CCL5 12.1 ng/mL, P<0.001; sCD40L 1.35 ng/mL, P<0.05), whereas elevated CCL18 levels were sustained for at least 2 days, then were decreased at 180 days after inclusion (34.5 ng/mL, P<0.001). Peripheral blood mononuclear cells showed increased protein expression of chemokine receptors CCR3 and CCR5 in CD3+ and CD14+ cells at baseline compared with 180 days after inclusion, whereas mRNA levels were downregulated, which was attributable in part to a postischemic release of human neutrophil peptide-3-positive neutrophils and in part to negative feedback. Finally, elevated CCL5 and CCL18 levels predicted future cardiovascular adverse events, whereas C-reactive protein and sCD40L levels did not. CONCLUSIONS: We are the first to report that CCL18 and CCL5 are transiently raised during episodes of UAP, and peak levels of both chemokines are indicative of refractory symptoms. Because levels of both chemokines, as well as of cognate receptor expression by circulating peripheral blood mononuclear cells, are increased during cardiac ischemia, this may point to an involvement of CCL5/CCL18 in the pathophysiology of UAP and/or post-UAP responses.

Monocyte gene expression in childhood obesity is associated with obesity and complexity of atherosclerosis in adults.

Childhood obesity coincides with increased numbers of circulating classical CD14++CD16- and intermediate CD14++CD16+ monocytes. Monocytes are key players in the development and exacerbation of atherosclerosis, which prompts the question as to whether the monocytosis in childhood obesity contributes to atherogenesis over the years. Here, we dissected the monocyte gene expression profile in childhood obesity using an Illumina microarray platform on sorted monocytes of 35 obese children and 16 lean controls. Obese children displayed a distinctive monocyte gene expression profile compared to lean controls. Upon validation with quantitative PCR, we studied the association of the top 5 differentially regulated monocyte genes in childhood obesity with obesity and complexity of coronary atherosclerosis (SYNTAX score) in a cohort of 351 adults at risk for ischemic cardiovascular disease. The downregulation of monocyte IMPDH2 and TMEM134 in childhood obesity was also observed in obese adults. Moreover, downregulation of monocyte TMEM134 was associated with a higher SYNTAX atherosclerosis score in adults. In conclusion, childhood obesity entails monocyte gene expression alterations associated with obesity and enhanced complexity of coronary atherosclerosis in adults.

Cytokine profiles in multifocal motor neuropathy and progressive muscular atrophy.

Multifocal motor neuropathy (MMN) and progressive muscular atrophy (PMA) are associated with IgM monoclonal gammopathy or the presence IgM anti-GM1-antibodies. To further investigate the pathophysiology of MMN and PMA we determined concentrations of 16 mainly B-cell associated inflammatory markers in serum from 25 patients with MMN, 55 patients with PMA, 25 patients with amyotrophic lateral sclerosis (ALS) and 50 healthy controls. Median serum concentrations of the 16 tested cytokines and chemokines were not significantly increased in patients with MMN or patients with PMA, irrespective of the presence of IgM monoclonal gammopathy or high IgM anti-GM1 antibodies. These results argue against a systemic B-cell mediated immune response underlying the pathogenesis of MMN and PMA.

Clinical experience with end-to-side nerve transfer.

A retrospective study was undertaken to determine the effectiveness of end-to-side nerve transfer. Twenty patients with peripheral nerve lesions of varying aetiology underwent 23 end-to-side nerve transfers over a 15-month period. The mean patient age was 30 years and 18 were male. The mean delay in presentation was 2.4 months. All underwent end-to-side nerve repairs and were reviewed in outpatients at regular intervals. Ten patients were lost to follow-up before 12 months and were therefore excluded from the study. The remaining ten patients, who had undergone 13 end-to-side procedures, had a mean follow-up period of 16 months. None demonstrated objective evidence of motor recovery at the end of the study period. Four patients had modest recovery of deep protective sensation, and two patients suffered a subtle degree of "donor" nerve morbidity. We have abandoned this technique in our centre in preference for standard nerve grafting techniques.

Correlation of CXCL10, tumor necrosis factor receptor type II, and galectin 9 with disease activity in juvenile dermatomyositis.

OBJECTIVE: Juvenile dermatomyositis (DM) is a systemic autoimmune disorder of unknown immunopathogenesis in which the immune system targets the microvasculature of skeletal muscles, skin, and other organs. The current mainstay of therapy is a steroid regimen in combination with other immunosuppressive treatments. To date, no validated markers for monitoring disease activity have been identified, which hampers personalized treatment. This study was undertaken to identify a panel of proteins specifically related to active disease in juvenile DM. METHODS: We performed a multiplex immunoassay for plasma levels of 45 proteins related to inflammation in 25 patients with juvenile DM in 4 clinically well-defined groups, as determined by clinical activity and treatment. We compared them to 14 age-matched healthy children and 8 age-matched children with nonautoimmune muscle disease. RESULTS: Cluster analysis of circulating proteins showed distinct profiles for juvenile DM patients and controls based on a group of 10 proteins. In addition to CXCL10, tumor necrosis factor receptor type II (TNFRII) and galectin 9 were significantly increased in active juvenile DM. The levels of these 3 proteins were tightly linked to active disease and correlated with clinical scores (as measured by the Childhood Myositis Assessment Scale and physician's global assessment of disease activity on a visual analog scale). CONCLUSION: Our findings indicate that CXCL10, TNFRII, and galectin 9 correspond to disease status in juvenile DM and thus could be helpful in monitoring disease activity and guiding treatment. Furthermore, they might provide new knowledge about the pathogenesis of this autoimmune disease.

Altered plasma adipokine levels and in vitro adipocyte differentiation in pediatric type 1 diabetes.

CONTEXT: Type 1 diabetes (T1D) is considered a proinflammatory condition. Adipose tissue involvement seems evident because adiponectin levels correlate with disease remission and administration of leptin suppresses the low-grade systemic inflammation in mice with T1D. Whether adipose tissue involvement in T1D already occurs at a young age is yet unknown. OBJECTIVE: The aim was to explore the extent of adipokine alterations in pediatric T1D and gain more insight into the mechanisms underlying the involvement of adipose tissue. DESIGN AND PARTICIPANTS: First, plasma adipokine profiling (24 adipokines) of 20 children with onset T1D, 20 children with long-standing T1D, and 17 healthy controls was performed using a recently developed and validated multiplex immunoassay. Second, the effects of diabetic plasma factors on preadipocyte proliferation and differentiation were studied in vitro. RESULTS: In children with onset and long-standing T1D, plasma adipokine profiling showed increased levels of various adipokines acting at the crossroads of adipose tissue function and inflammation, including CCL2/monocyte chemoattractant protein-1 and the novel adipokines cathepsin S, chemerin, and tissue inhibitor of metalloproteinase-1 (P < 0.05). Furthermore, onset and long-standing diabetic plasma significantly induced preadipocyte proliferation and adipocyte differentiation in vitro (P < 0.05). Two candidate plasma factors, glucose and the saturated fatty acid palmitic acid, did not affect proliferation or adipocyte differentiation in vitro but were found to increase CCL2 (monocyte chemoattractant protein-1) secretion by adipocytes. CONCLUSIONS: The adipogenic effects of diabetic plasma in vitro and the altered adipokine levels in vivo suggest adipose tissue involvement in the low-grade inflammation associated with T1D, already in pediatric patients.

Chemokines as risk factors for type 2 diabetes: results from the MONICA/KORA Augsburg study, 1984-2002.

AIMS/HYPOTHESIS: The chemokines monocyte chemoattractant protein-1 (MCP-1), IL-8 and interferon-gamma-inducible protein-10 (IP-10) are released by adipocytes and appear to be involved in atherosclerosis. We hypothesised that these chemokines may be risk factors for the development of type 2 diabetes. SUBJECTS AND METHODS: Using a case-cohort design based on data from the population-based Monitoring of Trends and Determinants in Cardiovascular Disease (MONICA)/Kooperative Gesundheitsforschung in der Region Augsburg/Cooperative Health Research in the Region of Augsburg (KORA Augsburg) study, chemokine levels at baseline were analysed in 526 individuals with and 1,695 individuals without incident type 2 diabetes. The mean follow-up time was 10.8 years. RESULTS: MCP-1 was associated with type 2 diabetes, largely independently of classic risk factors, whereas various clinical and metabolic parameters as well as lifestyle factors were major confounders of the association of IL-8 and IP-10 with type 2 diabetes. Further adjustment for C-reactive protein (CRP) and IL-6 had no impact on the observed associations. The hazard ratio (HR) for subjects with systemic concentrations of all three chemokines (MCP-1, IL-8 and IP-10) above the respective median compared with those with all chemokines below or equal to the median was 1.79 (95% CI 1.18-2.72) and was comparable with the HR for elevated CRP and IL-6 together (adjusted for age, sex, survey, BMI, systolic blood pressure, total cholesterol:HDL cholesterol ratio, physical activity, alcohol intake, smoking and parental history of diabetes). CONCLUSIONS/INTERPRETATION: Elevated concentrations of MCP-1, IL-8 and IP-10 are associated with incident type 2 diabetes. Whereas the association of IL-8 and IP-10 with diabetes was attenuated by multivariable adjustment, high MCP-1 levels contributed to diabetes risk independently of previously described clinical, metabolic and immunological risk factors.