Increased cortisol relative to adrenocorticotropic hormone predicts improvement during anti-tumor necrosis factor therapy in rheumatoid arthritis

The Role of Clock Genes in Maintaining Circadian Rhythm and Rheumatoid Arthritis Pathophysiology

Rheumatoid arthritis (RA) is a chronic, progressive autoimmune condition that affects up to 1% of the world population and symmetrically affects the joints leading to joint stiffness and decreased mobility. RA patients present with increased pain and chronic inflammation within their joint spaces, which researchers have linked to poorer sleep patterns, including difficulty falling asleep and non-restorative sleep. As such, identifying mediators of poor sleep quality among RA patients may improve their long-term quality of life. More recently, researchers identified an association between chronic inflammation in RA patients and their circadian rhythm. Altered circadian rhythms negatively impact the hypothalamic-pituitary-adrenal (HPA) axis and lead to altered cortisol release. Cortisol has shown to have a strong anti-inflammatory effect; when dysregulated, it may lead to increased pain experienced in RA patients. This literature review aims to provide insight into how chronic inflammation tied to RA pathophysiology may affect clock genes that are involved in maintaining the circadian rhythm. Specifically, this review focused on four common clock genes found dysregulated in RA patients: circadian locomotor output cycles kaput (CLOCK), brain and muscle ARNT like-1 (BMAL1), period (PER), and cryptochrome (CRY). Of the four clock genes discussed in this review, BMAL1 and PER are the most well-studied of the affected genes. Further knowledge surrounding clock genes and their dysregulated expression in RA may help guide therapy decisions for RA patients. Traditionally, disease-modifying antirheumatic drugs (DMARDs) have been used as first-line therapy for RA patients. Meanwhile, chronotherapy, optimizing drug release in a timed manner, has shown positive results in RA patients as well. Because of the association of altered circadian rhythms with increased symptom severity in RA patients, it seems highly plausible that DMARD therapy with chronotherapy may be an ideal therapeutic regimen for RA.

Gene Ontology Analysis Highlights Biological Processes Influencing Non-Response to Anti-TNF Therapy in Rheumatoid Arthritis

Anti-TNF therapy has significantly improved disease control in rheumatoid arthritis, but a fraction of rheumatoid arthritis patients do not respond to anti-TNF therapy or lose response over time. Moreover, the mechanisms underlying non-response to anti-TNF therapy remain largely unknown. To date, many single biomarkers of response to anti-TNF therapy have been published but they have not yet been analyzed as a system of interacting nodes. The aim of our study is to systematically elucidate the biological processes underlying non-response to anti-TNF therapy in rheumatoid arthritis using the gene ontologies of previously published predictive biomarkers. Gene networks were constructed based on published biomarkers and then enriched gene ontology terms were elucidated in subgroups using gene ontology software tools. Our results highlight the novel role of proteasome-mediated protein catabolic processes (p = 2.91 × 10⁻¹⁵) and plasma lipoproteins (p = 4.55 × 10⁻¹¹) in anti-TNF therapy response. The results of our gene ontology analysis help elucidate the biological processes underlying non-response to anti-TNF therapy in rheumatoid arthritis and encourage further study of the highlighted processes.

Operative management of colonic diverticular disease in the setting of immunosuppression: A systematic review and meta-analysis

BACKGROUND

Immunosuppressed patients with diverticular disease are at higher risk of postoperative complications, however reported rates have varied. The aim of this study is to compare postoperative outcomes in immunosuppressed and immunocompetent patients undergoing surgery for diverticular disease.

METHODS

Medline, EMBASE, and CENTRAL were searched. Articles were included if they compared immunosuppressed and immunocompetent patients undergoing surgery for diverticular disease.

RESULTS

From 204 citations, 11 studies with 2,977 immunosuppressed patients and 780,630 immunocompetent patients were included. Mortality was greater in immunosuppressed patients compared to immunocompetent patients for emergent surgery (RR 1.91, 95%CI 1.24-2.95, p < 0.01), but not elective surgery (RR 1.70, 95%CI 0.14-20.47, p = 0.68). Morbidity was greater in immunosuppressed patients compared to immunocompetent patients for elective surgery (RR 2.18, 95%CI 1.02-4.65, p = 0.04), but not emergent surgery (RR 1.40, 95%CI 0.68-2.90, p = 0.37).

CONCLUSIONS

Increased consideration for elective operation may preclude the need for emergent surgery and the associated increase in postoperative mortality.

Insensitivity versus poor response to tumour necrosis factor inhibitors in rheumatoid arthritis: a retrospective cohort study

Background

With advancement in the treatment options of rheumatoid arthritis (RA), optimising the outcomes of difficult-to-treat patients has become increasingly important in clinical practice. In particular, insensitivity to first-line biologic disease-modifying anti-rheumatic drugs (bDMARD) is becoming a significant problem because it may decrease the treatment adherence of patients. This study aimed to compare RA patients with an insensitivity and those with a poor response to initial treatment with tumour necrosis factor inhibitors (TNFis), which are the most frequently used bDMARDs.

Methods

This is a retrospective cohort study using clinical data from the FIRST registry. bDMARD-naïve RA patients treated with tumour necrosis factor inhibitors (TNFis) from August 2003 to May 2019 were included and categorised into three groups: TNFi insensitivity, poor response to TNFis and controls. TNFi insensitivity was defined as follows: (1) discontinuation of TNFi treatment within 22 weeks due to lack of any response, or (2) an increase in the disease activity score in 28 joints–C-reactive protein (DAS28-CRP) of > 0.6 at week 22 compared with week 0. Among the remaining patients, those with a DAS28-CRP > 2.6 at week 22 were categorised in the poor response group.

Results

Of the included patients, 94 were classified in the insensitivity, 604 in the poor response and 915 in the control. A higher DAS28-CRP before treatment was a risk factor for a poor response but not for insensitivity. In contrast, dose escalation of infliximab decreased the risk of a poor response but not that of insensitivity.

Conclusions

In future research, poor and insensitivity to bDMARDs should be assessed separately to fully elucidate the aetiology of, and risk factors for, bDMARD refractoriness.

Role of 11β-HSD type 1 in abnormal HPA axis activity during immune-mediated arthritis

Patients with chronic immune-mediated arthritis exhibit abnormal hypothalamo-pituitary-adrenal (HPA) axis activity. The basis for this abnormality is not known. Immune-mediated arthritis is associated with increased extra-adrenal synthesis of active glucocorticoids by the 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) enzyme. 11β-HSD1 is expressed in the central nervous system, including regions involved in HPA axis regulation. We examined whether altered 11β-HSD1 expression within these regions contributes to HPA axis dysregulation during arthritis. The expression of 11β-HSD1, and other components of glucocorticoid signaling, were examined in various brain regions and the pituitary gland of mice with experimentally induced arthritis. Two arthritis protocols were employed: The K/BxN spontaneous arthritis model for chronic arthritis and the K/BxN serum transfer arthritis model for acute arthritis. 11β-HSD1 mRNA (Hsd11b1) was expressed in the hippocampus, hypothalamus, cortex, cerebellum and pituitary gland. Hypothalamic Hsd11b1 expression did not change in response to arthritis in either model. Pituitary Hsd11b1 expression was however significantly increased in both chronic and acute arthritis models. Hippocampal Hsd11b1 was decreased in acute but not chronic arthritis. Chronic, but not acute, arthritis was associated with a reduction in hypothalamic corticotropin-releasing hormone and arginine vasopressin expression. In both models, serum adrenocorticotropic hormone and corticosterone levels were no different from non-inflammatory controls. These findings demonstrate inflammation-dependent regulation of Hsd11b1 expression in the pituitary gland and hippocampus. The upregulation of 11β-HSD1 expression in the pituitary during both chronic and acute arthritis, and thus, an increase in glucocorticoid negative feedback, could contribute to the abnormalities in HPA axis activity seen in immune-mediated arthritis.

Mathematical modeling of the circadian dynamics of the neuroendocrine-immune network in experimentally induced arthritis

The circadian dynamics of important neuroendocrine-immune mediators have been implicated in progression of rheumatoid arthritis pathophysiology, both clinically as well as in animal models. We present a mathematical model that describes the circadian interactions between mediators of the hypothalamic-pituitary-adrenal (HPA) axis and the proinflammatory cytokines. Model predictions demonstrate that chronically elevated cytokine expression results in the development of adrenal insufficiency and circadian variability in paw edema. Notably, our model also predicts that an increase in mean secretion of corticosterone (CST) after the induction of the disease is accompanied by a decrease in the amplitude of the CST oscillation. Furthermore, alterations in the phase of circadian oscillation of both cytokines and HPA axis mediators are observed. Therefore, by incorporating the circadian interactions between the neuroendocrine-immune mediators, our model is able to simulate important features of rheumatoid arthritis pathophysiology.

Chronic inflammatory systemic diseases: An evolutionary trade-off between acutely beneficial but chronically harmful programs

It has been recognized that during chronic inflammatory systemic diseases (CIDs) maladaptations of the immune, nervous, endocrine and reproductive system occur. Maladaptation leads to disease sequelae in CIDs. The ultimate reason of disease sequelae in CIDs remained unclear because clinicians do not consider bodily energy trade-offs and evolutionary medicine. We review the evolution of physiological supersystems, fitness consequences of genes involved in CIDs during different life-history stages, environmental factors of CIDs, energy trade-offs during inflammatory episodes and the non-specificity of CIDs. Incorporating bodily energy regulation into evolutionary medicine builds a framework to better understand pathophysiology of CIDs by considering that genes and networks used are positively selected if they serve acute, highly energy-consuming inflammation. It is predicted that genes that protect energy stores are positively selected (as immune memory). This could explain why energy-demanding inflammatory episodes like infectious diseases must be terminated within 3–8 weeks to be adaptive, and otherwise become maladaptive. Considering energy regulation as an evolved adaptive trait explains why many known sequelae of different CIDs must be uniform. These are, e.g. sickness behavior/fatigue/depressive symptoms, sleep disturbance, anorexia, malnutrition, muscle wasting—cachexia, cachectic obesity, insulin resistance with hyperinsulinemia, dyslipidemia, alterations of steroid hormone axes, disturbances of the hypothalamic-pituitary-gonadal (HPG) axis, hypertension, bone loss and hypercoagulability. Considering evolved energy trade-offs helps us to understand how an energy imbalance can lead to the disease sequelae of CIDs. In the future, clinicians must translate this knowledge into early diagnosis and symptomatic treatment in CIDs.

Personalized biological treatment for rheumatoid arthritis: a systematic review with a focus on clinical applicability

OBJECTIVES

To review studies that address prediction of response to biologic treatment in RA and to explore the clinical utility of the studied (bio)markers.

METHODS

A search for relevant articles was performed in PubMed, Embase and Cochrane databases. Studies that presented predictive values or in which these could be calculated were selected. The added value was determined by the added value on prior probability for each (bio)marker. Only an increase/decrease in chance of response ⩾15% was considered clinically relevant, whereas in oncology values >25% are common.

RESULTS

Of the 57 eligible studies, 14 (bio)markers were studied in more than one cohort and an overview of the added predictive value of each marker is presented. Of the replicated predictors, none consistently showed an increase/decrease in probability of response ⩾15%. However, positivity of RF and ACPA in case of rituximab and the presence of the TNF-α promoter 308 GG genotype for TNF inhibitor therapy were consistently predictive, yet low in added predictive value. Besides these, 65 (bio)markers studied once showed remarkably high (but not validated) predictive values.

CONCLUSION

We were unable to address clinically useful baseline (bio)markers for use in individually tailored treatment. Some predictors are consistently predictive, yet low in added predictive value, while several others are promising but await replication. The challenge now is to design studies to validate all explored and promising findings individually and in combination to make these (bio)markers relevant to clinical practice.

Determinants of adrenal androgen hypofunction in premenopausal females with rheumatoid arthritis

The aim of our study was to investigate adrenocortical function in the context of disease activity and inflammatory status in premenopausal RA females. Adrenal glucocorticoid and androgen responses to the 1 microg ACTH 1-24 test were investigated in 23 premenopausal RA and in 15 age- and BMI-matched healthy females. Twelve RA patients were on low-dose prednisone (<8.5 mg/day). Patients with DAS28>3.2 had lower (p<0.05) total plasma cortisol, 17-hydroxyprogesterone, dehydroepiandrosterone and androstenedione responses in the ACTH test compared to healthy controls. Patients with DAS28>3.2 had lower (p<0.05) dehydroepiandrosterone response in the ACTH test compared to patients with DAS28</=3.2. C-reactive protein (CRP), DAS28, and interleukin (IL)-6 negatively correlated with androstenedione response to ACTH 1-24. Responses of all measured adrenal steroids were lower (p<0.05) in patients on low-dose glucocorticoids compared to healthy controls. RA patients not treated with glucocorticoids had lower total cortisol response (p=0.038) but did not differ in free plasma cortisol in the ACTH test. The results indicate an association of increased disease activity with a decrease in adrenal androgen production in RA and normal cortisol bioavailability in patients not treated with glucocorticoids.

From endocrine to rheumatism: do gut hormones play roles in rheumatoid arthritis?

RA is characterized by chronic inflammation in the musculoskeletal system, in which TNF-α is the key cytokine trigger. TNF-α, previously known as cachectin, is implicated in the modulation of body composition and energy expenditure. Gut hormones, including acyl ghrelin, des-acyl ghrelin, GIP, GLP-1 and PYY, have been known to be the major regulators of appetite, nutrition, energy expenditure and body mass formation. Emerging evidence indicates that blockade of TNF-α by biologics not only ameliorates rheumatoid inflammation, but can affect the secretion and action of gut hormones on appetite, body composition, energy expenditure, muscle catabolism and bone remodelling. A link between the gastrointestinal endocrine axis and the immune system may be established through the interaction of proinflammatory cytokines, including TNF-α and these gut hormones. With the ever-increasing understanding of rheumatoid inflammation and the invention of more biologics to modulate the cytokine network, more attention should be given to the possible immunomodulatory roles of gut hormones in autoimmune inflammatory reactions.

Role of neuroendocrine and neuroimmune mechanisms in chronic inflammatory rheumatic diseases--the 10-year update

BACKGROUND

Neuroendocrine immunology in musculoskeletal diseases is an emerging scientific field. It deals with the aspects of efferent neuronal and neurohormonal bearing on the peripheral immune and musculoskeletal systems. This review aims to add new information that appeared since 2001.

SEARCH STRATEGY

The following PubMed search sentence was used to find a total of 15,462 references between 2001 and March 2013: "(rheum* OR SLE OR vasculitis) AND (nerve OR hormone OR neurotransmitter OR neuropeptide OR steroid)." In a continuous process, year by year, this search strategy yielded relevant papers that were screened and collected in a database, which build the platform of this review.

RESULTS

The main findings are the anti-inflammatory role of androgens, the loss of androgens (androgen drain), the bimodal role of estrogens (support B cells and inhibit macrophages and T cells), increased conversion of androgens to estrogens in inflammation (androgen drain), disturbances of the gonadal axis, inadequate amount of HPA axis hormones relative to inflammation (disproportion principle), biologics partly improve neuroendocrine axes, anti-corticotropin-releasing hormone therapies improve inflammation (antalarmin), bimodal role of the sympathetic nervous system (proinflammatory early, anti-inflammatory late-most probably due to catecholamine-producing local cells), anti-inflammatory role of alpha melanocyte-stimulating hormone, vasoactive intestinal peptide, and the Vagus nerve via α7 nicotinergic receptors. Circadian rhythms of hypothalamic origin are responsible for circadian rhythms of symptoms (neuroimmune link revealed). Important new pain-sensitizing immunological pathways were found in the last decade.

CONCLUSIONS

The last decade brought much new information that gave birth to the first therapies of chronic inflammatory diseases on the basis of neuroendocrine immune targets. In addition, a new theory linked evolutionary medicine, neuroendocrine regulation of distribution of energy-rich fuels, and volume regulation that can explain many disease sequelae in patients with chronic inflammatory diseases.

Activity of the neuroendocrine axes in patients with polymyalgia rheumatica before and after TNF-α blocking etanercept treatment

Introduction

In this study, we evaluated the activity of the neuroendocrine axes in patients with polymyalgia rheumatica (PMR) before and after tumor necrosis factor (TNF)-α-blocking etanercept treatment, which previously has been shown to reduce interleukin 6 (IL-6) and C-reactive protein (CRP) markedly in PMR.

Methods

Plasma samples were collected from 10 glucocorticoid-naïve patients with PMR and 10 matched controls before and after etanercept treatment (25 mg biweekly for 2 weeks). The primary end points were pre- and posttreatment levels of adrenocorticotropic hormone (ACTH), cortisol, adrenaline, thyroid-stimulating hormone (TSH), follicle-stimulating hormone (FSH), prolactin, and insulin-like growth factor 1 (IGF-1).

Results

Before TNF-α-blocking treatment, plasma TNF-α, ACTH, and cortisol levels were higher in patients versus controls (P < 0.05 and P < 0.001, respectively); during TNF-α blockade in patients, levels of both hormones decreased (P < 0.05 and P < 0.01, respectively), whereas levels in controls increased (P < 0.05), abolishing the pretreatment differences. Pretreatment adrenaline levels were more than twice as high in patients than in controls (P < 0.01); after treatment in patients, levels had decreased (P < 0.05) but remained higher versus controls (P < 0.05). Levels of the other hormones never differed significantly between groups (P > 0.05).

Conclusions

In PMR, TNF-α may increase the activities of the hypothalamic-pituitary-adrenal and the hypothalamic-sympthoadrenomedullary axes. Secretion of TSH, FSH, prolactin, and IGF-1 is not clearly changed in PMR.

Trial registration

ClinicalTrials.gov (NCT00524381).

Effects of adrenal sensitivity, stress- and cue-induced craving, and anxiety on subsequent alcohol relapse and treatment outcomes

CONTEXT

Alcoholism is a chronic, relapsing illness in which stress and alcohol cues contribute significantly to relapse risk. Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, increased anxiety, and high alcohol craving have been documented during early alcohol recovery, but their influence on relapse risk has not been well studied.

OBJECTIVES

To investigate these responses in treatment-engaged, 1-month-abstinent, recovering alcohol-dependent patients relative to matched controls (study 1) and to assess whether HPA axis function, anxiety, and craving responses are predictive of subsequent alcohol relapse and treatment outcome (study 2).

DESIGN

Experimental exposure to stress, alcohol cues, and neutral, relaxing context to provoke alcohol craving, anxiety, and HPA axis responses (corticotropin and cortisol levels and cortisol to corticotropin ratio) and a prospective 90-day follow-up outcome design to assess alcohol relapse and aftercare treatment outcomes.

SETTING

Inpatient treatment in a community mental health center and hospital-based research unit.

PARTICIPANTS

Treatment-engaged alcohol-dependent individuals and healthy controls.

MAIN OUTCOME MEASURES

Time to alcohol relapse and to heavy drinking relapse.

RESULTS

Significant HPA axis dysregulation, marked by higher basal corticotropin level and lack of stress- and cue-induced corticotropin and cortisol responses, higher anxiety, and greater stress- and cue-induced alcohol craving, was seen in the alcohol-dependent patients vs the control group. Stress- and cue-induced anxiety and stress-induced alcohol craving were associated with fewer days in aftercare alcohol treatment. High provoked alcohol craving to both stress and to cues and greater neutral, relaxed-state cortisol to corticotropin ratio (adrenal sensitivity) were each predictive of shorter time to alcohol relapse.

CONCLUSIONS

These results identify a significant effect of high adrenal sensitivity, anxiety, and increased stress- and cue-induced alcohol craving on subsequent alcohol relapse and treatment outcomes. Findings suggest that new treatments that decrease adrenal sensitivity, stress- and cue-induced alcohol craving, and anxiety could be beneficial in improving alcohol relapse outcomes.

Functional disturbance of the stress-adaptation system in patients with scleroderma

There have been several reports indicating the association between recent stress experiences and the onset or the exacerbation of rheumatic diseases, although few such reports exist in patients with scleroderma (SSc). The present study was performed to elucidate whether there were any functional disturbances in the neuro-endocrine-immune system as a homeostatic system upon stress in SSc patients. Various serum levels of stress-related hormones and cytokines were examined before and after a mental calculation stress test, and a basal questionnaire study of sense of coherence (SOC, which is related to the ability to cope with stress), recent stress experiences, and quality of life (QOL) was performed in 17 SSc patients and in 38 healthy volunteers. Physical QOL state was impaired in patients, but there were no differences in recent stress experiences and SOC scores between patients and controls. Basal serum cortisol levels were similar in patients and controls, but increased levels of proinflammatory cytokine and noradrenalin were seen in SSc patients. Characteristically, contrary to the control group, whose cortisol levels increased significantly following the mental calculation stress test, no significant increase was observed in the patients when post-test cortisol levels were compared to pre-test levels, suggesting a defect in the normal cortisol response upon stress in SSc patients. The present results suggest that there may be impaired function of the neuro-endocrine-immune system upon stress in SSc patients.

Hypothalamus-Pituitary-Adrenal Axis Function in Patients with Rheumatoid Arthritis Treated with Nighttime-Release Prednisone

Objective.

To investigate the effects of longterm low-dose chronotherapy with modified-release (MR) prednisone for rheumatoid arthritis (RA) on the hypothalamus-pituitary-adrenal (HPA) axis as part of the Circadian Administration of Prednisone in Rheumatoid Arthritis (CAPRA-1) study. This consisted of a 3-month active-controlled phase and a 9-month open-label extension with MR prednisone including patients previously treated with prednisone (ClinicalTrials.gov number NCT00146640).

Methods.

Corticotropin-releasing hormone (CRH) tests were performed on 28 patients at 3 timepoints: at baseline on prestudy immediate-release (IR) prednisone, after the 3-month double-blind phase on either IR prednisone or MR prednisone, and after the 9-month open-label extension on MR prednisone. Changes of cortisol were assessed and compared to individual patients’ efficacy and safety data.

Results.

The increase (mean, SD) of cortisol plasma concentrations after injection of corticorelin was 5.5 (4.37) μg/dl on IR prednisone at baseline (n = 21) and 5.3 (4.07) μg/dl on MR prednisone at 12 months (n = 22). Numbers of normal/suppressed/no response reactions did not differ among treatments. Switching from IR to MR prednisone did not influence responses, nor did longterm treatment of up to 12 months with MR prednisone. No worsening of adrenal impairment was observed on treatment with nighttime-release prednisone in patients with low responsiveness to CRH testing before the treatment with MR prednisone.

Conclusion.

Treatment with nighttime-release prednisone did not change adrenocortical function over 12 months. We presume that chronotherapy with this nighttime-release prednisone may improve the efficacy of longterm low-dose glucocorticoid treatment in patients with RA.

Anti-TNF therapy restores the hypothalamic-pituitary-adrenal axis

Tumor necrosis factor (TNF) inhibitors are associated with greater improvements in the symptoms and signs of rheumatoid arthritis (RA) and, more importantly, a lower risk of joint damage. TNF is an important mediator of the alterations in neuroendocrine axes characterizing RA. Long-term therapy with anti-TNF agents sensitizes the pituitary gland and improves adrenal androgen secretion, thus stimulating an alternative form of anti-inflammatory action.

Psoriatic arthritis: clinical improvement and correlation with hormone axes in etanercept-treated patients

In a chronic inflammatory disease, such as rheumatoid arthritis (RA), the hypothalamic-pituitary-adrenal axis is altered in three ways: (1) the inflammation-related spontaneous and stimulated secretion of cortisol is inadequate; (2) the inflammation-related secretion of adrenocorticotropic hormone (ACTH) is low; and (3) the levels of adrenal androgens decrease. In patients with RA, long-term therapy with anti-TNF therapy sensitizes the pituitary gland and improves adrenal androgen secretion. We have recently found that the mean serum levels of ACTH, cortisol, 17-hydroxyprogesterone (17OHP), and androstenedione (ASD) in 11 prednisolone-naïve patients with psoriatic arthritis did not markedly change during 12 weeks of etanercept treatment, nor did the serum cortisol/ACTH ratio. However, the greater increase in serum cortisol in comparison with serum 17OHP or ASD was related to clinical improvement, which indicates that the improvement was more related to the higher cortisol levels.

Impaired hypothalamo-pituitary-adrenal axis in patients with ankylosing spondylitis

BACKGROUND

To investigate the hypothalamic-pituitary- adrenal (HPA) axis in patients with ankylosing spondylitis (AS) and healthy controls.

METHODS

Forty-nine AS patients and 20 healthy controls were included. Lowdose ACTH test (LDST) was used to assess the HPA axis. Basal cortisol, stimulated peak cortisol levels, and acutephase reactants [C-reactive protein (CRP), erythrocyte sedimentation rate, and fibrinogen] were studied. Bath Ankylosing Spondylitis Functional Index, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), and Bath Ankylosing Spondylitis Metrology Index were also evaluated.

RESULTS

Patient and control groups were not different regarding age, sex, body mass index and waist circumference (WC). Basal cortisol levels did not show a significant difference between groups. However, cortisol increment after low-dose ACTH was significantly impaired in AS subjects with respect to controls (20.0+/-4.4 vs 24+/-2.2 microg/dl, p<0.001). Eleven AS patients had impaired cortisol peak after LDST when a cortisol cut-off is accepted as 500 nmol/l (18 microg/dl) and none of the controls exhibited a peak cortisol responses to LDST<500 nmol/l. Comparison of AS subjects who were receiving anti-tumor necrosis factor (TNF) (no.=23), and conventional therapy (no.=26) yielded similar basal and peak cortisol concentrations. Peak cortisol concentrations were associated with basal cortisol, impaired cortisol response, CRP, and fibrinogen. Impaired cortisol response (subjects with peak cortisol levels <18 microg/dl) was significantly correlated with basal and peak cortisol concentrations and BASDAI.

CONCLUSION

Our results indicate an increased prevalence of subclinical glucocorticoid deficiency in AS patients. Anti-TNF treatment seems not to have effect on HPA axis.

Insights into endocrine-immunological disturbances in autoimmunity and their impact on treatment

The neuroendocrine immune (NEI) system is regarded as a fundamental network for the maintenance of health status (homeostasis), and it plays an important role in several systemic diseases, including autoimmune disorders. Among the major players of NEI pathways are steroid hormones of the adrenal (cortisol) and gonadal glands (sex hormones), neurohormones such as melatonin, and more recently the vitamin D endocrine system. Estrogens, melatonin and chronic stress (inducing decreased adrenal glucocorticoid release over a long time) strongly modulate the NEI system and stimulate the immune response. The vitamin D endocrine system is regarded as a potential immunosuppressive factor. Consequently, estrogens (especially in patients affected by B-cell-driven immunity) and melatonin should be avoided, and glucocorticoids (as replacement therapy) and vitamin D are allowed in the treatment of autoimmunity.