Management of pregnancy in autoimmune rheumatic diseases: maternal disease course, gestational and neonatal outcomes and use of medications in the prospectiveItalian P-RHEUM.it study

OBJECTIVES

To investigate pregnancy outcomes in women with autoimmune rheumatic diseases (ARD) in the Italian prospective cohort study P-RHEUM.it.

METHODS

Pregnant women with different ARD were enrolled for up to 20 gestational weeks in 29 Rheumatology Centres for 5 years (2018-2023). Maternal and infant information were collected in a web-based database.

RESULTS

We analysed 866 pregnancies in 851 patients (systemic lupus erythematosus was the most represented disease, 19.6%). Maternal disease flares were observed in 135 (15.6%) pregnancies. 53 (6.1%) pregnancies were induced by assisted reproduction techniques, 61 (7%) ended in miscarriage and 11 (1.3%) underwent elective termination. Obstetrical complications occurred in 261 (30.1%) pregnancies, including 2.3% pre-eclampsia. Two cases of congenital heart block were observed out of 157 pregnancies (1.3%) with anti-Ro/SSA. Regarding treatments, 244 (28.2%) pregnancies were treated with glucocorticoids, 388 (44.8%) with hydroxychloroquine, 85 (9.8%) with conventional synthetic disease-modifying anti-rheumatic drugs and 122 (14.1%) with biological disease-modifying anti-rheumatic drugs. Live births were 794 (91.7%), mostly at term (84.9%); four perinatal deaths (0.5%) occurred. Among 790 newborns, 31 (3.9%) were small-for-gestational-age and 169 (21.4%) had perinatal complications. Exclusive maternal breast feeding was received by 404 (46.7%) neonates. The Edinburgh Postnatal Depression Scale was compiled by 414 women (52.4%); 89 (21.5%) scored positive for emotional distress.

CONCLUSIONS

Multiple factors including preconception counselling and treat-to-target with pregnancy-compatible medications may have contributed to mitigate disease-related risk factors, yielding limited disease flares, good pregnancy outcomes and frequency of complications which were similar to the Italian general obstetric population. Disease-specific issues need to be further addressed to plan preventative measures.

Stopping bDMARDs at the beginning of pregnancy is associated with disease flares and preterm delivery in women with rheumatoid arthritis

Objectives: Women with Rheumatoid Arthritis (RA) can experience flares during pregnancy that might influence pregnancy outcomes. We aimed at assessing the disease course during pregnancy and identifying risk factors for flares.

Methods: Data about prospectively-followed pregnancies in RA were retrospectively collected before conception, during each trimester and in the post-partum period. Clinical characteristics, disease activity (DAS28-CRP3), medication use, and pregnancy outcomes were analysed with regard to disease flares.

Results: Among 73 women who had a live birth, 64 (88%) were in remission/low disease activity before conception. During pregnancy, a flare occurred in 27 (37%) patients, mainly during first and second trimester. Flares during pregnancy were associated with the discontinuation of bDMARDs at positive pregnancy test (55% of patients with flare vs. 30% of patients with no flare, p 0.034, OR 2.857, 95% CI 1.112–8.323) and a previous use of >1 bDMARDs (33% of patients with flare vs. 10% of patients with no flare, p 0.019, OR 4.1, 95%CI 1.204–13.966). Preterm pregnancies were characterised by higher values of CRP [10 mg/L (5–11) vs. 3 mg/L (2.5–5), p 0.01] and DAS28-CRP3 [4.2 (1.9–4.5) vs. 1.9 (1.7–2.6), p 0.01] during the first trimester as compared with pregnancies at term. Preterm delivery was associated with the occurrence of flare during pregnancy (flare 27% vs. no-flare 7%, p 0.034, OR 4.625, 95%CI 1.027–20.829).

Conclusion: Preterm delivery in RA patients was associated with flares during pregnancy. Flares occurred more frequently after the discontinuation of bDMARDs at positive pregnancy test. Women with aggressive RA on treatment with bDMARDs should be considered as candidates for continuing bDMARDs during pregnancy in order to reduce the risk of flare and adverse pregnancy outcomes.

AB0686 THE IMPACT OF SYSTEMIC SCLEROSIS (SSc) ON WOMEN’S HEALTH EVALUATED WITH A NEW SSc-SPECIFIC PATIENT-REPORTED QUESTIONNAIRE

Background

Systemic Sclerosis (SSc) can strongly affect the quality of life of affected women. We aimed at designing a SSc-specific, patient-reported questionnaire to explore different aspects of women’s health.

Objectives

The questionnaire was created together with Obstetricians-Gynecologists (70 questions, 5 sections) and administered to consecutive patients with SSc (2013 ACR/EULAR classification criteria) regularly attending our Clinic in May-December 2021. The Female Sexual Function Index (FSFI) questionnaire was also administered.

Methods

The questionnaire was created together with Obstetricians-Gynecologists (70 questions, 5 sections) and administered to consecutive patients with SSc (2013 ACR/EULAR criteria) regularly attending our Clinic in the period May-December 2021. The Female Sexual Function Index (FSFI) questionnaire was also administered.

Results

Questionnaires were proposed to 114 patients; among 100 who accepted to participate (median age 59.0 [43.0-67.0], median disease duration 11.0 [6.0-17.0] years), 48% had received SSc diagnosis during reproductive age (<45 years). The cutaneous involvement was limited in 75% and anti-centromere were positive in 44%. A regular gynecological follow-up was not declared by 60% of the patients. Considering patients with SSc-diagnosis in reproductive age: 73% never discussed contraceptive methods with their SSc-Clinicians; 63% desired a pregnancy after diagnosis, but 30% did not satisfied the desired family size; about 50% reported they did not know whether a woman with SSc could experience disease worsening or take safe medications during pregnancy, and have children also affected by SSc. 77% of patients declared improvement or stability of SSc manifestations during pregnancy. Table 1 shows the comparison of pregnancies before and after SSc diagnosis, based on data reported by the patients. Regarding sexuality, 59% reported that SSc negatively affected it by vaginal dryness (67%), digital ulcers (37%), gastro-intestinal disease (37%) and dyspnea (20%). Among 39 patients completing FSFI, 67% had sexual dysfunction.

Table 1.

Results are presented as median [IQR] or number/number available data (%) based on patients answering the question. Continuous variables were compared with Mann-Whitney test; categorical variables with Fisher’s exact test.

Total pregnancies (n= 189)Pregnancies after diagnosis (n= 42)Pregnancies before diagnosis (n= 147)p-value OR [95% CI]Maternal age at conception, years28.0 [24.0-32.0]32.0 [28.0-39.0]27.0 [23.0-30.0]< 0.001Live births152/189 (80.4)31/42 (73.8)121/147 (82.3)0.221Cesarean sections36/135 (26.7)17/31 (54.8)19/104 (18.3)< 0.0015.43 [2.30-12.9]Preterm births <37 weeks32/109 (29.4)7/32 (21.9)25/77 (32.5)0.269Preterm births <34weeks7/32 (21.8)2/7 (28.6)5/25 (20.0)0.632Birth weight, kilograms3.3 [2.8-3.6]3.1 [2.5-3.5]3.3 [3.0-3.7]0.049≥ 1 Adverse Pregnancy Outcomes15/113 (13.3)8/31 (25.8)7/82 (8.5)0.0163.73 [1.22-11.39]Gestational hypertension4/113 (3.5)3/31 (9.7)1/82 (1.2)0.062Preeclampsia1/113 (0.9)1/31 (3.2)0/82 (0.0)0.274Eclampsia0/113 (0.0)0/31 (0.0)0/82 (0.0)1.000HELLP syndrome1/113 (0.9)0/31 (0.0)1/82 (1.2)1.000Gestational diabetes3/113 (2.7)2/31 (6.5)1/82 (1.2)0.182Intra Uterine Growth Restriction4/113 (3.5)2/31 (6.5)2/82 (2.4)0.302Perinatal deaths2/134 (1.5)0/32 (0.0)2/102 (1.9)1.000Neonatal Intensive Care Unit Admission11/134 (8.2)6/32 (18.8)5/102 (4.9)0.0224.48 [1.27-15.84]Perinatal infections8/134 (8.2)3/32 (9.4)5/102 (4.9)0.396Breastfeeding92/132 (69.7)22/32 (68.8)70/100 (70.0)0.893

Conclusion

The newly created specific questionnaire was instrumental to facilitate physician-patient communication about ‘women’s health’, particularly in the field of sexuality which is characterized by a high frequency of dysfunction. Adverse outcomes are possible during SSc pregnancies and should be discussed during the multidisciplinary preconception counselling, along with measures to possibly reduce their risk.

Acknowledgements

GILS (Gruppo Italiano Lotta Sclerodermia) is kindly acknowledged for supporting the study with a grant.

Disclosure of Interests

None declared

Reproductive Issues and Pregnancy Implications in Systemic Sclerosis

Systemic sclerosis (SSc) is a rare systemic autoimmune disease that can influence reproductive health. SSc has a strong female predominance, and the disease onset can occur during fertility age in almost 50% of patients. Preconception counseling, adjustment of treatment, and close surveillance during pregnancy by a multidisciplinary team, are key points to minimize fetal and maternal risks and favor successful pregnancy outcomes. The rates of spontaneous pregnancy losses are comparable to those of the general obstetric population, except for patients with diffuse cutaneous SSc and severe internal organ involvement who may carry a higher risk of abortion. Preterm birth can frequently occur in women with SSc, as it happens in other rheumatic diseases. Overall disease activity generally remains stable during pregnancy, but particular attention should be paid to women with major organ disease, such as renal and cardiopulmonary involvement. Women with such severe involvement should be thoroughly informed about the risks during pregnancy and possibly discouraged from getting pregnant. A high frequency of sexual dysfunction has been described among SSc patients, both in females and in males, and pathogenic mechanisms of SSc may play a fundamental role in determining this impairment. Fertility is overall normal in SSc women, while no studies in the literature have investigated fertility in SSc male patients. Nevertheless, some considerations regarding the impact of some immunosuppressive drugs should be done with male patients, referring to the knowledge gained in other rheumatic diseases.

AB0822 BREASTFEEDING AMONG WOMEN WITH RHEUMATIC DISEASES: ANALYSIS OF DATA FROM THE P-RHEUM.IT STUDY

Background:

The World Health Organization recommends that infants should be exclusively breastfed until the age of 6 months. The aim of this study was to assess the ratio of breastfeeding patients with Rheumatic Diseases (RD) and to identify possible causes of its discontinuation.

Objectives:

The aim of this study was to assess the ratio of breastfeeding patients with Rheumatic Diseases (RD) and to identify possible causes of its discontinuation.

Methods:

This study was embedded in the P-RHEUM.it register, as a nationwide prospective cohort study collecting data of pregnancies in inflammatory RD. Pregnancies, enrolled until the 20th week of pregnancy, are followed from pregnancy until 6 months postpartum. At baseline, sociodemographic parameters, obstetric history, comorbidities are reported. During pregnancy, the course of maternal disease, development of foetus and complications are reported. After delivery, the pregnancy outcome, data on lactation and child development are collected.

Results:

From May 2018 to May 2020 data of 349 patients were available. Data on lactation were available in 44 pregnancies. Two months after delivery 37 were continuing breastfeeding (n=26) or mixed feeding (n=11), while 7 were using formula feeding. Among patients using formula feeding 2 had a diagnosis of rheumatoid arthritis (RA), 1 of juvenile idiopathic arthritis, 1 of undifferentiated arthritis (UA), 1 of anti-phospholipid syndrome (APS), 1 of vasculitis and 1 of systemic lupus erythematosus. The reasons of formula feeding were the following: 2 for agalactia, 2 for personal preferences, 3 for drug-related concerns (1 for physician’s decision in a patient with APS; 2 for maternal concerns about drugs in patients with RA and UA treated respectively with Adalimumab and Tocilizumab). At 6 months 30 continued breastfeeding (n=23) or mixed feeding (n=7) and 14 formula feeding. The reasons of formula feeding were available in 9 patients: 3 for agalactia, 2 for personal preferences, 2 for physician’s decision in a patient with APS and in a patient positive for anti-phospholipid antibodies; 2 for maternal concerns about drugs.

Conclusion:

Preliminary data of this prospective study demonstrate a high percentage of breastfeeding/mixed feeding after delivery and after 6 months among women with RD. Drug related concerns are the main reason of discontinuation of breastfeeding, although medication results compatible with lactation. Using our results, strategies supporting patients with RD whishing to breastfeed may be developed.

References:

[1]Carina Gotestam Sporken et al. The EULAR points to consider for use of antirheumatic drugs before pregnancy, and during pregnancy and lactation. Ann Rheum Dis 2016.

[2]Sammaritano et al. 2020 American College of Rheumatology Guideline for the management of reproductive health in rheumatic and muscoloskeletal diseases, Arthritis Rheumatol. 2020.

Acknowledgements:

Authors would like to thank SIR study center and all patients who accepted to partecipate to our study

Disclosure of Interests:

None declared

Triple Antiphospholipid (aPL) Antibodies Positivity Is Associated With Pregnancy Complications in aPL Carriers: A Multicenter Study on 62 Pregnancies

Objective: Antiphospholipid antibodies (aPL) are risk factors for thrombosis and adverse pregnancy outcomes (APO). The management of the so called “aPL carriers” (subjects with aPL positivity without the clinical criteria manifestations of APS) is still undefined. This study aims at retrospectively evaluating the outcomes and the factors associated with APO and maternal complications in 62 pregnant aPL carriers.

Methods: Medical records of pregnant women regularly attending the Pregnancy Clinic of 3 Rheumatology centers from January 1994 to December 2015 were retrospectively evaluated. Patients with concomitant autoimmune diseases or other causes of pregnancy complications were excluded.

Results: An aPL-related event was recorded in 8 out of 62 patients (12.9%) during pregnancy: 2 thrombosis and 6 APO. At univariate analysis, factors associated with pregnancy complications were acquired risk factors (p:0.008), non-criteria aPL manifestations (p:0.024), lupus-like manifestations (p:0.013), and triple positive aPL profile (p:0.001). At multivariate analysis, only the association with a triple aPL profile was confirmed (p:0.01, OR 21.3, CI 95% 1.84–247). Patients with triple aPL positivity had a higher rate of pregnancy complications, despite they were more frequently receiving combined treatment of low dose aspirin (LDA) and low molecular weight heparin (LMWH) at prophylactic dose.

Conclusion: This study highlights the importance of risk stratification in pregnant aPL carriers, in terms of both immunologic and non-immunologic features. Combination treatment with LDA and LMWH did not prevent APO in some cases, especially in carriers of triple aPL positivity. Triple positive aPL carriers may deserve additional therapeutic strategies during pregnancy.

Efficacy of combined ethinyloestradiol (0.035 mg) and cyproterone acetate (2 mg) in acne and hirsutism in women with polycystic ovary syndrome

The effects of an oral contraceptive containing ethinyloestradiol and cyproterone acetate on acne and hirsutism were studied in 82 women with polycystic ovary syndrome. The contraceptive was administered for 48 consecutive cycles. Hormone and ultrasound evaluations were carried out at baseline and after 48 treatment cycles. Acne and hirsutism were evaluated after 18, 24, 36 and 48 treatment cycles. Acne resolved in all patients within 24 treatment cycles. Mild and moderate hirsutism resolved within 48 treatment cycles. Severe hirsutism persisted although it changed to mild or moderate in most of the affected women.

Risk identification of osteoporosis in postmenopausal women by a simple algorithm based on ultrasound densitometry and body mass index

Dual-energy X-ray absorptiometry (DXA) method is the main device for diagnosing osteoporosis; this method, however, involves the use of expensive equipment. Ultrasound method, being portable, noninvasive, and cost-effective, seems to be an appropriate screening device to identify subjects at risk of osteoporosis. Two hundred and twenty-four postmenopausal women (mean age: 57.9+/-6.2yr) were recruited at 2 Menopause Centers. All subjects were assessed by phalangeal Quantitative Ultrasound (QUS) and by DXA at femur and rachis. Applying the first-level screening strategy, the following risk factors were considered: (1) Amplitude Dependent Speed-of-Sound T-score<-1.8 standard deviation (SD) or Ultrasound Bone Profile Index T-score<-1.8SD; (2) body mass index (BMI)<20kg/m(2). BMI identified 25 subjects (11%) of the total population as at risk, the QUS parameters 100 subjects (45%), and the combination of the 2 showed 118 subjects (53%). The percentage of osteoporotics identified by BMI was 17%, by QUS 78%, and by the combination of the two 90%. The sensitivity of this algorithm was 90%; 53% of the subjects would undergo a further densitometric evaluation, the remaining 47% were correctly identified as not at risk. The diagnostic work up proposed appears effective to be indicated for extensive clinical employment, thanks also to its simplicity.

Relationships between circulating hormone levels, mammographic percent density and breast cancer risk factors in postmenopausal women

BACKGROUND

Endogenous hormones and insulin-like growth factors (IGF) play a central role in breast cancer development. Mammographic density, an important breast cancer risk factor, has been associated with these biomarkers in premenopausal women. The aim of this study was to assess the relationships between circulating hormones, clinical features related to breast cancer risk and mammographic density in postmenopausal women.

SUBJECTS AND METHODS

The study included 226 postmenopausal women participating in a clinical prevention trial. We performed baseline measurements of mammographic percent density and circulating levels of estradiol, sex-hormone binding globulin (SHBG), follicle stimulating hormone (FSH), prolactin, C-terminal cross-link telopeptide, IGF-I, and IGF binding protein-3.

RESULTS

Median age and time since last menses were 52 years and 15 months, respectively. Median body mass index was 24.1 kg/m(2). After adjusting for age and body mass index, estradiol was the only biomarker significantly correlated with mammographic density (r = 0.17; P = 0.04). Women with normal body mass index had higher mammographic density (P < 0.001), higher SHBG (P < 0.0001), higher FSH (P = 0.002) and lower estradiol levels (P = 0.01) than those who were overweight. Women who had previous biopsies for benign breast disease had a higher mammographic density (P = 0.006).

CONCLUSIONS

In these recently postmenopausal women, mammographic percent density is directly associated with circulating estradiol levels. Our results provide further support to the role of circulating hormones in breast cancer risk.

Quality of life assessment in a chemoprevention trial: fenretinide and oral or transdermal HRT

BACKGROUND

Oral conjugated equine estrogen (CEE) and medroxyprogesterone acetate (MPA) relief menopause symptoms, but may increase breast cancer risk, while the effects of transdermal estradiol (E2) and MPA are less known. In previous studies, fenretinide decreased second breast malignancies in premenopausal but not in postmenopausal women, suggesting a hormone-sensitizing effect. We have evaluated the quality of life through a self-administered questionnaire during a randomized study of oral CEE or transdermal E2 and fenretinide or placebo.

METHODS

A total of 226 postmenopausal women were randomly assigned to either CEE 0.625mg/day and placebo (n=55), or CEE and fenretinide 100mg/bid (n=56), or E2, 50microg/day and placebo (n=59), or E2 and fenretinide (n=56) for 12 months. Sequential MPA 10mg/day was added in all groups. Treatment effects were investigated using a validated questionnaire, the Menopause Quality of Life questionnaire (MENQOL).

RESULTS

Oral CEE and transdermal E2 have a comparable activity in reducing menopausal symptoms (p=ns). Both routes ameliorate significantly the symptoms after 1 year of treatment (p<0.0001). Fenretinide does not modify the effects of hormonal replacement therapy.

CONCLUSIONS

Oral CEE and transdermal E2 have similar effect on menopausal symptoms relief. The choice of the best estrogen replacement therapy (ERT) route should be decided based on a careful analysis of all the clinical aspects of every subject, considering that transdermal therapy may have a safer effect on the cardiovascular system.

A two-by-two factorial trial comparing oral with transdermal estrogen therapy and fenretinide with placebo on breast cancer biomarkers

PURPOSE

Oral conjugated equine estrogen (CEE) and medroxyprogesterone acetate (MPA) increase breast cancer risk, whereas the effect of transdermal estradiol (E2) and MPA is less known. Fenretinide may decrease second breast malignancies in premenopausal women but not in postmenopausal women, suggesting a hormone-sensitizing effect. We compared the 6 and 12-month changes in insulin-like growth factor-I (IGF-I), IGF-binding protein-3 (IGFBP-3), IGF-I:IGFBP-3 ratio, sex-hormone binding-globulin, and computerized mammographic percent density during oral CEE or transdermal E2 with sequential MPA and fenretinide or placebo.

EXPERIMENTAL DESIGN

A total of 226 recent postmenopausal healthy women were randomly assigned in a two-by-two factorial design to either oral CEE 0.625 mg/day (n = 111) or transdermal E2, 50 microg/day (n = 115) and to fenretinide 100 mg/twice a day (n = 112) or placebo (n = 114) for 12 months. Treatment effects were investigated by the Kruskall-Wallis test and analysis of covariance. P values were two-sided.

RESULTS

After 12 months, oral CEE decreased IGF-I by 26% [95% confidence interval (CI), 22-30%] and increased sex-hormone binding-globulin by 96% (95% CI, 79-112%) relative to baseline, whereas no change occurred with transdermal E2 (P < 0.001 between groups). Fenretinide decreased IGFBP-3 relative to placebo (P = 0.04). Percentage of breast density showed an absolute increase of 3.5% (95% CI, 2.5-4.6%) during hormone therapy without differences between groups (P = 0.39).

CONCLUSIONS

Oral CEE has more favorable changes than transdermal E2 on circulating breast cancer risk biomarkers but gives similar effects on mammographic density. Fenretinide exerted little modulation on most biomarkers. The clinical implications of these findings require additional studies.

Endometrial evaluation with transvaginal ultrasound during hormone therapy: a prospective multicenter study

OBJECTIVE

To assess the value of endometrial thickness as a marker of endometrial abnormality risk during hormone therapy (HT) and to study the correlation between abnormal bleeding and abnormal endometrial histology in patients with thick endometrium.

DESIGN

Prospective multicenter study.

SETTING

University and general hospitals outpatient centers.

PATIENT(S)

Postmenopausal women (702) on HT.

INTERVENTION(S)

Biendometrial thickness was measured by transvaginal sonography (TVS) between day 5 and day 10 after the last P intake and, when present, after the end of the menstrual-like bleeding.

MAIN OUTCOME MEASURE(S)

Hysteroscopy and biopsy were performed within 5 days from TVS on all patients with an endometrial thickness >4.5 mm (precision scale 0.5 mm).

RESULT(S)

Endometrial thickness >4.5 mm was observed in 20.5% of patients. One hundred sixteen hysteroscopies and biopsies were performed. Hyperplasia, polyps, and endocavitary fibroids were detected in 15%, 24%, and 8% of cases, respectively. The positive predictive value of TVS examination was 47%. Endometrial thickness was the only variable significantly and independently associated with histologic abnormalities and endocavitary fibroids. Abnormal bleeding occurred in 17.1% of patients. Among 17 patients detected with thick endometrium and hyperplasia, 8 cases showed abnormal bleeding.

CONCLUSION(S)

Sonographic endometrial thickness of 4.5 mm provides a sensitive tool to select HT patients who might benefit from hysteroscopy and biopsy. Abnormal bleeding is not a sensitive sign of hyperplasia in patients with thick endometrium.

Effect of transdermal estradiol and oral conjugated estrogen on C-reactive protein in retinoid-placebo trial in healthy women

BACKGROUND

The increase in C-reactive protein (CRP) during oral conjugated equine estrogen (CEE) may explain the initial excess of cardiovascular disease observed in clinical studies. Because the effect of transdermal estradiol (E2) on CRP is unclear, we compared CRP changes after 6 and 12 months of transdermal E2 and oral CEE in a randomized 2x2 retinoid-placebo trial.

METHODS AND RESULTS

A total of 189 postmenopausal women were randomized to 50 microg/d transdermal E2 and 100 mg BID of the retinoid fenretinide (n=45), 50 microg/d transdermal E2 and placebo (n=49), 0.625 mg/d oral CEE and 100 mg BID fenretinide (n=46), or 0.625 mg/d oral CEE and placebo (n=49) for 1 year. Sequential medroxyprogesterone acetate was added in each group. Relative to baseline, CRP increased by 10% (95% CI -9% to 33%) and by 48% (95% CI 22% to 78%) after 6 months of transdermal E2 and oral CEE, respectively. The corresponding figures at 12 months were 3% (95% CI -14% to 23%) for transdermal E2 and 64% (95% CI 38% to 96%) for oral CEE. Fenretinide did not change CRP levels at 6 and 12 months relative to placebo. Relative to oral CEE, the mean change in CRP after 12 months of transdermal E2 was -48% (95% CI -85% to -7%, P=0.012), whereas fenretinide was associated with a mean change of -1% (95% CI -34% to 40%, P=0.79) compared with placebo.

CONCLUSIONS

In contrast to oral CEE, transdermal E2 does not elevate CRP levels up to 12 months of treatment. The implications for early risk of coronary heart disease require further studies.