Change of clinical characteristics of ulcerative colitis in Japan: analysis of 844 hospital-based patients from 1981 to 2000

Differences in Clinical Practice and Disease Course Between Elderly-Onset and Long-Standing Elderly Ulcerative Colitis: A Single-Center Study in Japan

The optimal immunosuppressive therapy for elderly patients with ulcerative colitis (UC) remains unclear. We aimed to evaluate clinical practice and prognosis in elderly patients with UC through comparing between those with elderly-onset UC (EOUC) and those with long-standing elderly UC (LEUC). In this retrospective single-center cohort study, we evaluated elderly patients with UC aged ≥ 60 in August 2022 through collecting medical record data from the time of diagnosis of UC until August 2022. The patients were divided into two groups based on age at disease onset: EOUC (age at onset, ≥ 60 years) and LEUC (age at onset, < 60 years). We assessed the cumulative rates of systemic steroid and molecular targeted drug (MTD) initiation, and colectomy. We enrolled 97 eligible patients (EOUC group, n = 30; LEUC group, n = 67). The cumulative rates of initiating systemic steroid (46% vs. 22% at 1 year, respectively; P = 0.002) and MTD (17% vs. 5% at 1 year, respectively; P = 0.002) were higher in the EOUC group than in the LEUC group. In multivariate analysis, elderly onset was significantly associated with systemic steroid (hazard ratio [HR] 2.74, 95% confidence interval [CI] 1.43-5.29; P = 0.003) and MTD (HR 2.76, 95% CI 1.30-5.87; P = 0.008) initiation. Cumulative colectomy rates did not differ significantly between the two groups. Patients with EOUC were initiated on systemic steroids and MTDs sooner following disease onset than patients with LEUC. Our findings suggest rapid progression and refractoriness in patients with EOUC.

Clinical practice and outcome of patients with elderly-onset ulcerative colitis: Insights from a nationwide claims database study in Japan

Background and Aim

The number of older patients with ulcerative colitis is increasing; however, limited data exist regarding the differences between elderly- and non-elderly-onset ulcerative colitis. We aimed to compare the clinical practice and course of elderly-onset ulcerative colitis with those of non-elderly-onset ulcerative colitis.

Methods

We selected older patients with ulcerative colitis and divided them into the elderly- and non-elderly-onset ulcerative colitis groups according to their age at onset. We compared the cumulative systemic steroid-free, molecular targeting drug-free, and surgery-free rates between the two groups. We performed a multivariate analysis to identify the clinical factors related to systemic steroid administration, the use of molecular targeting drugs, surgery, and death.

Results

We collected data of 2669 and 277 elderly and non-elderly-onset ulcerative colitis patients, respectively. The cumulative systemic steroid-free rate of elderly-onset ulcerative colitis was significantly lower than that of non-elderly-onset ulcerative colitis. However, no difference was observed in the cumulative molecular targeting drugs and surgery-free rates between the two groups. Elderly-onset ulcerative colitis significantly increased the risk of systemic steroid administration and death but not the use of molecular targeting drugs and surgery.

Conclusion

The disease severity of ulcerative colitis and clinical practice may not differ between the elderly- and non-elderly-onset groups. However, elderly-onset ulcerative colitis was associated with increased mortality risk. Thus, we need to pay attention to the patients' condition and appropriate timing of surgery for patients with elderly-onset ulcerative colitis.

Impact of Female Gender in Inflammatory Bowel Diseases: A Narrative Review

Inflammatory bowel diseases show a gender bias, as reported for several other immune-mediated diseases. Female-specific differences influence disease presentation and activity, leading to a different progression between males and females. Women show a genetic predisposition to develop inflammatory bowel disease related to the X chromosome. Female hormone fluctuation influences gastrointestinal symptoms, pain perception, and the state of active disease at the time of conception could negatively affect the pregnancy. Women with inflammatory bowel disease report a worse quality of life, higher psychological distress, and reduced sexual activity than male patients. This narrative review aims to resume the current knowledge of female-related features in clinical manifestations, development, and therapy, as well as sexual and psychological implications related to inflammatory bowel disease. The final attempt is to provide gastroenterologists with a roadmap of female-specific differences, to improve patients' diagnosis, management, and treatment.

The long-term effect of biologics in patients with ulcerative colitis emerging from a large Japanese cohort

To gain a better understanding of the effects of biologics, we evaluated clinical outcomes in patients with moderate to severe exacerbations of ulcerative colitis (UC). This retrospective, multicenter study retrieved the entire clinical courses of UC patients who began treatments between 2004 and 2018. All exacerbations and clinical parameters, including treatment details for exacerbations and both remission and re-exacerbation dates, were identified during the observation period. Two different endpoints, the cumulative incidence rates of surgical resection and re-exacerbation, were evaluated separately in moderate to severe exacerbation events. Among 1401 patients, 1626 exacerbation events were determined according to a partial Mayo score (remission: < 2, mild: 2-4, moderate: 5-7, and severe: > 7). During the observation period, as administration rates of biologics increased, both surgical resection and hospitalization rates decreased, for 959 moderate to severe exacerbation events. We confirmed that biologics significantly reduced the cumulative re-exacerbation rate in moderate to severe exacerbation events during the study period compared with suboptimal therapies (a 0.507-fold decreased risk according to COX regression analysis, P < 0.001). However, they had not enough impact in reducing the cumulative incidence rate of surgical resection in moderate to severe exacerbation events that were corticosteroid-refractory or dependent (a 0.878-fold decreased risk according to COX regression analysis, P = 0.606). Biologics may improve remission duration, but these agents had no significant impact in reducing the risk of surgical resection in moderate to severe active UC.

Evidence-based clinical practice guidelines for inflammatory bowel disease 2020

Inflammatory bowel disease (IBD) is a general term for chronic or remitting/relapsing inflammatory diseases of the intestinal tract and generally refers to ulcerative colitis (UC) and Crohn's disease (CD). Since 1950, the number of patients with IBD in Japan has been increasing. The etiology of IBD remains unclear; however, recent research data indicate that the pathophysiology of IBD involves abnormalities in disease susceptibility genes, environmental factors and intestinal bacteria. The elucidation of the mechanism of IBD has facilitated therapeutic development. UC and CD display heterogeneity in inflammatory and symptomatic burden between patients and within individuals over time. Optimal management depends on the understanding and tailoring of evidence-based interventions by physicians. In 2020, seventeen IBD experts of the Japanese Society of Gastroenterology revised the previous guidelines for IBD management published in 2016. This English version was produced and modified based on the existing updated guidelines in Japanese. The Clinical Questions (CQs) of the previous guidelines were completely revised and categorized as follows: Background Questions (BQs), CQs, and Future Research Questions (FRQs). The guideline was composed of a total of 69 questions: 39 BQs, 15 CQs, and 15 FRQs. The overall quality of the evidence for each CQ was determined by assessing it with reference to the Grading of Recommendations Assessment, Development and Evaluation approach, and the strength of the recommendation was determined by the Delphi consensus process. Comprehensive up-to-date guidance for on-site physicians is provided regarding indications for proceeding with the diagnosis and treatment.

Tofacitinib as Induction and Maintenance Therapy in Japanese Patients with Active Ulcerative Colitis

Background

Tofacitinib is an oral, small molecule Janus kinase inhibitor approved in Japan for the treatment of ulcerative colitis (UC). Differences in the safety profile of tofacitinib in Japanese patients versus the global population, such as a higher risk of herpes zoster, have been reported.

Objectives

We conducted post hoc analyses of tofacitinib treatment in Japanese patients with moderate-to-severe UC in two global phase III studies.

Methods

In OCTAVE Induction 1 (NCT01465763), 62 patients were randomized to placebo or tofacitinib 10 mg twice daily (b.i.d.). In OCTAVE Sustain (NCT01458574), 39 patients with clinical response in OCTAVE Induction 1 were re-randomized to placebo, tofacitinib 5 mg, or 10 mg b.i.d. Efficacy endpoints included: remission (primary endpoint; total Mayo score ≤2; no individual subscore >1; rectal bleeding subscore 0); mucosal healing (Mayo endoscopic subscore ≤1); clinical response (≥30% and ≥3-point decrease from induction study baseline total Mayo score; decrease in rectal bleeding subscore ≥1 or absolute subscore ≤1). Adverse events (AEs) and clinical laboratory parameters were recorded.

Results

At week 8 of OCTAVE Induction 1, 22.4% of patients achieved remission with tofacitinib (placebo, 7.7%). At week 52 of OCTAVE Sustain, 31.3% and 66.7% of patients receiving tofacitinib 5 and 10 mg b.i.d., respectively, achieved remission (placebo, 9.1%). The occurrence of AEs or serious AEs in Japanese patients was generally similar to that in the global study population, with no new or unexpected safety risks observed.

Conclusions

Although patient numbers were small, tofacitinib demonstrated numerically greater efficacy versus placebo among Japanese patients in OCTAVE Induction 1 and OCTAVE Sustain, with a safety profile consistent with that of the global study population.

Establishment and Development of the First Biobank of Inflammatory Bowel Disease, Suspected to Primary Immunodeficiency Diseases in Iran

Background:

Inflammatory bowel disease (IBD) might be an immunodeficiency rather than an excessive inflammatory reaction. IBD, suspected to primary immunodeficiency diseases biobank (IBDSPIDB) as a resource for researches can help improve the prevention, diagnosis, and illness treatment and the health promotion throughout the society. Therefore, we launched the biobank of IBDSPID for the first time in Iran.

Materials and Methods:

This study was designed to provide the IBDSPIDB to have a high-quality DNA, RNA, and cDNA. Among of 365 patients, 39 have inclusion criteria that were as below: (1) IBD diagnosis before 5 years of age. (2) Resistance to conventional therapy of IBD. (3) Severe IBD. (4) Signs of SPID (including ear infections or pneumonia or recurrent sinus within the 1-year period; failure to thrive; poor response to the prolonged use of antibiotics; persistent thrush or skin abscesses; or a family history of PID).

Results:

Out of 39 patients, 51.3% were males. The mean age was 32.92 ± 15.90 years old. Ulcerative colitis (79.5%) was more than Crohn's disease. The majority of patients (50.0%) had severe IBDSPID. Resistance to drugs and consanguinity was 12.9% and 47.4%, respectively. Age at onset in 65.8% of patients was after 17 years old. Patients with autoimmune, allergy, and immunodeficiency disease history were 33.3%, 33.3%, and 10.36%, respectively. RNA and cDNA yields large quantities of high-quality DNA obtained and stored.

Conclusion:

Our biobank would be valuable for future genetic and molecular study to be more about the relation between IBD and PID.

Evidence-based clinical practice guidelines for inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic disorder involving mainly the intestinal tract, but possibly other gastrointestinal and extraintestinal organs. Although etiology is still uncertain, recent knowledge in pathogenesis has accumulated, and novel diagnostic and therapeutic modalities have become available for clinical use. Therefore, the previous guidelines were urged to be updated. In 2016, the Japanese Society of Gastroenterology revised the previous versions of evidence-based clinical practice guidelines for ulcerative colitis (UC) and Crohn's disease (CD) in Japanese. A total of 59 clinical questions for 9 categories (1. clinical features of IBD; 2. diagnosis; 3. general consideration in treatment; 4. therapeutic interventions for IBD; 5. treatment of UC; 6. treatment of CD; 7. extraintestinal complications; 8. cancer surveillance; 9. IBD in special situation) were selected, and a literature search was performed for the clinical questions with use of the MEDLINE, Cochrane, and Igaku Chuo Zasshi databases. The guidelines were developed with the basic concept of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. Recommendations were made using Delphi rounds. This English version was produced and edited based on the existing updated guidelines in Japanese.

Changing epidemiological trends of inflammatory bowel disease in Asia

Inflammatory bowel disease (IBD) has become more common in Asia over the past few decades. The rate of increase in prevalence of the disease varies greatly in Asia, with several countries in East Asia experiencing a more than doubled increase in IBD prevalence over the past decade. Historically, ulcerative colitis (UC) is more common than Crohn's disease (CD) in Asia. However, a reverse trend is beginning to appear in more developed countries in Asia such as Japan, Korea, and Hong Kong. While Asian IBD patients share many similarities with their Western counterparts, there are important differences with significant clinical implications. In Asia, there are more men with CD, more ileo-colonic involvement in CD, less familial aggregation, fewer extra-intestinal manifestations and worse clinical outcomes for older-onset patients with UC. These differences are likely related to the different genetic makeup and environmental exposures in different regions. Evaluation of the differences and rates in epidemiologic trends may help researchers and clinicians estimate disease burden and understand the reasons behind these differences, which may hold the key to unravel the etiology of IBD.

Natural History of Elderly-onset Ulcerative Colitis: Results from a Territory-wide Inflammatory Bowel Disease Registry

BACKGROUND AND AIMS

Data on the natural history of elderly-onset ulcerative colitis [UC] are limited. We aimed to investigate clinical features and outcomes of patients with elderly-onset UC.

METHODS

Patients with a confirmed diagnosis of UC between 1981 and 2013, from 13 hospitals within a territory-wide Hong Kong Inflammatory Bowel Disease Registry, were included. Clinical features and outcomes of elderly-onset patients, defined as age ≥ 60 years at diagnosis, were compared with those of non-elderly-onset disease [< 60 years at diagnosis].

RESULTS

We identified 1225 patients, of whom 12.8% [157/1225; 56.1% male] had elderly-onset UC. Median duration of follow-up was 11 years [interquartile range, 6-16 years]. Age-specific incidence of elderly-onset UC increased from 0.1 per 100000 persons before 1991 to 1.3 per 100000 persons after 2010. There were more ex-smokers [32.2% vs. 12.2%, p < 0.001] and higher proportion of comorbidities [p < 0.001] in elderly-onset than non-elderly-onset patients. Disease extent, corticosteroids, immunosuppressants use, and colectomy rates were similar between the two groups. Elderly-onset disease was an independent risk factor for cytomegalovirus infection [odds ratio 2.9, 95% confidence interval 1.6-5.2, p < 0.001]. More elderly-onset patients had Clostridium difficile infection [11.0% vs. 5.4%, p = 0.007], hospitalisation for UC exacerbation [50.6% vs. 41.8%, p = 0.037], colorectal cancer [3.2% vs. 0.9%, p = 0.033], all-cause mortality [7.0% vs. 1.0%, p < 0.001], and UC-related mortality [1.9% vs. 0.2%, p = 0.017] than non-elderly-onset patients.

CONCLUSIONS

Elderly-onset UC patients are increasing in number. These patients have higher risk of opportunistic infections, hospitalisation, colorectal cancer, and mortality than non-elderly-onset patients. Management and therapeutic strategies in this special group need careful attention.

The th17/treg immune balance in ulcerative colitis patients with two different chinese syndromes: dampness-heat in large intestine and spleen and kidney yang deficiency syndrome

Objective. To investigate the Th17/Treg immune balance in the ulcerative colitis (UC) patients with two Chinese syndrome: dampness-heat in large intestine (DHLI) and spleen and kidney Yang deficiency (SKYD). Methods. Ninety UC patients (45 were diagnosed with DHLI and 45 with SKYD syndrome) and 23 healthy people were recruited. The serumIL-17 and TGF-β1 levels of these participants were measured with ELISA; the expression of IL-17 and TGF-β 1 in colonic mucosa tissue was determined with immunohistochemistry and the percentage of Th17 and Treg in peripheral blood with flow cytometry. Results. The levels of IL-17 and Th17 were significantly higher in both DHLI and SKYD groups than in healthy control group and higher in DHLI than in SKYD group (P < 0.05). The levels of TGF-β1 and Treg were significantly lower in the two UC patients groups than in healthy control group; and lower in SKYD group than in DHLI group (P < 0.05). Conclusions. UC with DHLI syndrome could be characterized by the elevation of Th17 and IL-17 levels, which indicated an accentuation of inflammatory reaction; UC with SKYD syndrome could be characterized by the reduction of serum Treg and TGF-β1 levels, which represented a depression of immune tolerance.

Long-term prognosis of ulcerative colitis and its temporal change between 1977 and 2013: a hospital-based cohort study from Korea

BACKGROUND AND AIMS

No previous large-scale studies have evaluated the prognosis of ulcerative colitis (UC) over a period of three decades in a non-Caucasian population. The aims of this study were to update the current information on the natural course of UC in a sizable cohort of Korean patients and to evaluate changes in the treatment paradigms and prognosis of UC over time.

METHODS

We retrospectively analyzed 2802 Korean UC patients who visited Asan Medical Center. We divided the study subjects into three groups based on the year of diagnosis (cohort 1: 1977–1999; cohort 2: 2000–2006; and cohort 3: 2007–2013).

RESULTS

Five-year cumulative probabilities of prescription of thiopurines (azathioprine or 6-mercaptopurine) and anti-tumor necrosis factor (anti-TNF) agents were 4.1% and 0.0%, respectively, in cohort 1 and 27.9% and 12.7%, respectively, in cohort 3 (P < 0.001). A total of 209 patients (7.5%) underwent colectomy, producing cumulative probabilities of colectomy at 10, 20 and 30 years after diagnosis of 7.8%, 14.2% and 21.3%, respectively. The cumulative probability of colectomy was especially low in patients first diagnosed at our center: 3.1% at 10 years and 4.5% at 20 years. Moreover, the cumulative probability of colectomy decreased significantly over the last 30 years (P = 0.039).

CONCLUSION

Thiopurines and anti-TNF agents are used increasingly more frequently and earlier, while the colectomy rate has decreased over the last 30 years in Korean patients with UC. Korean UC patients may have a better clinical course than Western cases, as indicated by a lower colectomy rate.

Old age at diagnosis is associated with favorable outcomes in korean patients with inflammatory bowel disease

Background/Aims

Despite the rising incidence and prevalence of inflammatory bowel disease (IBD) in Asian populations, data regarding clinical characteristics of patients in Asia based on age at diagnosis are relatively sparse. The aim of this study was to compare clinical characteristics based on the age at diagnosis according to the Montreal Classification in Korean IBD patients.

Methods

We recruited consecutive patients with IBD at two tertiary hospitals and retrospectively reviewed their medical information. Patients were divided into three groups according to their age at diagnosis: youth (<17 years), young adult (17-40 years), and middle-old (>40 years). The main clinical characteristics for comparison were the achievement of a remission state at the last follow-up visit, cumulative rate of surgery, and cumulative use of immunomodulators and tumor necrosis factor-α (TNFα) blockers during the follow-up period.

Results

In total, 346 IBD patients were included (Crohn's disease [CD] 146 and ulcerative colitis 200; 36 youth, 202 young adult, and 113 middle-old). The middle-old group with CD was characterized by a predominance of uncomplicated behavior (P=0.013) and a lower frequency of perianal disease (P=0.009). The middle-old group was associated more with a less aggressive disease course than the younger group, as shown by more frequent remission (P=0.004), being less likely to undergo surgery (P<0.001), and lower cumulative use of immunomodulators and TNFα blockers (P<0.001).

Conclusions

Age at diagnosis according to the Montreal Classification is an important prognostic factor for Korean IBD patients.

Clinical epidemiology of ulcerative colitis in Arabs based on the Montréal classification

AIM: To determine the clinical, epidemiological and phenotypic characteristics of ulcerative colitis (UC) in Saudi Arabia by studying the largest cohort of Arab UC patients.

METHODS: Data from UC patients attending gastroenterology clinics in four tertiary care centers in three cities between September 2009 and September 2013 were entered into a validated web-based registry, inflammatory bowel disease information system (IBDIS). The IBDIS database covers numerous aspects of inflammatory bowel disease. Patient characteristics, disease phenotype and behavior, age at diagnosis, course of the disease, and extraintestinal manifestations were recorded.

RESULTS: Among 394 UC patients, males comprised 51.0% and females 49.0%. According to the Montréal classification of age, the major chunk of our patients belonged to the A2 category for age of diagnosis at 17-40 years (68.4%), while 24.2% belonged to the A3 category for age of diagnosis at > 40 years. According to the same classification, a majority of patients had extensive UC (42.7%), 35.3% had left-sided colitis and 29.2% had only proctitis. Moreover, 51.3% were in remission, 16.6% had mild UC, 23.4% had moderate UC and 8.6% had severe UC. Frequent relapse occurred in 17.4% patients, infrequent relapse in 77% and 4.8% had chronic disease. A majority (85.2%) of patients was steroid responsive. With regard to extraintestinal manifestations, arthritis was present in 16.4%, osteopenia in 31.4%, osteoporosis in 17.1% and cutaneous involvement in 7.0%.

CONCLUSION: The majority of UC cases were young people (17-40 years), with a male preponderance. While the disease course was found to be similar to that reported in Western countries, more similarities were found with Asian countries with regards to the extent of the disease and response to steroid therapy.

Clinical characteristics and treatment of inflammatory bowel disease: a comparison of Eastern and Western perspectives

Inflammatory bowel disease (IBD) is a chronic, relapsing intestinal inflammatory disorder with unidentified causes. Both environmental factors and genetic aspects are believed to be crucial to the pathogenesis of IBD. The incidence and prevalence of IBD have recently been increasing throughout Asia, presumably secondary to environmental changes. This increasing trend in IBD epidemiology necessitates specific health care planning and education in Asia. To this end, we must gain a precise understanding of the distinctive clinical and therapeutic characteristics of Asian patients with IBD. The phenotypes of IBD reportedly differ considerably between Asians and Caucasians. Thus, use of the same management strategies for these different populations may not be appropriate. Moreover, investigation of the Asian-specific clinical aspects of IBD offers the possibility of identifying causative factors in the pathogenesis of IBD in this geographical area. Accordingly, this review summarizes current knowledge of the phenotypic manifestations and management practices of patients with IBD, with a special focus on a comparison of Eastern and Western perspectives.

Second peak in the distribution of age at onset of ulcerative colitis in relation to smoking cessation

BACKGROUND AND AIM

The prevalence of ulcerative colitis (UC) is increasing steadily in Japan. In Western countries, a bimodal distribution, with UC onset peaks in youth and middle age, is observed, and smoking cessation is reported as a risk factor for UC. However, there are few reports on a bimodal distribution of onset age among Japanese patients. Therefore, the distribution of onset age and factors related to late onset (i.e. onset at 50 years old or later) were investigated in UC patients in Japan.

METHODS

A questionnaire survey of UC patients was conducted to investigate the distribution of the age of onset and factors that may be related to UC onset in a Japanese university hospital.

RESULTS

Among 465 UC patients, 343 patients responded. In the distribution of onset age, a large peak was seen in patients aged 10-20s, and small peaks were seen at age 40-44 years and then in 50-60s. In addition, the onset age was older in the UC patients diagnosed in 2001 or later than in those diagnosed in 2000 or earlier. Late onset was more common among the UC patients diagnosed in 2001 or later (vs 2000 or earlier: interaction odds ratio = 4.98, 95% CI: 2.21-11.25, P < 0.01) and among former smokers (vs never-smokers: interaction odds ratio = 2.93, 95% CI: 1.40-6.14, P < 0.01) on multivariate analysis.

CONCLUSIONS

Similar to UC patients in Western countries, a bimodal distribution of onset age was also observed in Japanese UC patients, and smoking cessation may partly contribute to the increase in late-onset UC patients in recent years in Japan.

Racial/Ethnic and regional differences in the prevalence of inflammatory bowel disease in the United States

BACKGROUND

The magnitude of racial/ethnic and regional differences in the prevalence of inflammatory bowel disease (IBD) in the United States remains largely unknown.

AIMS

To estimate differences in the prevalence of IBD by race/ethnicity and region.

METHODS

The Medical Expenditure Panel Survey, a nationally representative survey of US households and medical conditions, was used. A multivariate logistic model was used in statistical analysis.

RESULTS

Among 202,468 individuals surveyed during 1996-2007, 316 were diagnosed with IBD (26 Blacks, 21 Hispanics, and 5 Asians). The prevalence of IBD was higher in Whites [Crohn's disease: 154; ulcerative colitis (UC): 89] than Blacks (Crohn's disease: 68; UC: 25), Hispanics (Crohn's disease: 15; UC: 35), and Asians (Crohn's: 45; UC: 40) (all p < 0.05, except for UC in Asians). The differences in Crohn's disease between Whites and minorities and the difference in UC between Whites and Blacks remained significant in multivariate analysis. In multivariate analysis, there was no regional difference in the prevalence of Crohn's disease, but the prevalence of UC was higher in the Northeast than the South (p < 0.05).

CONCLUSIONS

There were significant racial/ethnic differences in the prevalence of IBD in the USA. The underlying etiology of these differences warrants additional research.

Seasonal variations in the onset of ulcerative colitis in Japan

AIM: To investigate seasonal variations in the onset and relapse of ulcerative colitis (UC) in Japanese patients.

METHODS: Between 1994 and 2006, 198 Japanese patients diagnosed with UC according to conventional criteria in an academic hospital were enrolled for onset evaluation. Among 265 Japanese patients with UC who were observed for more than 12 mo, 165 patients relapsed (239 times) and were enrolled for relapse evaluation. The patients’ symptoms were recorded each month for 12 consecutive years.

RESULTS: There was monthly seasonality in symptom onset during October and March for UC. The onset of symptoms in UC patients frequently occurred during the winter. Variation in UC onset was observed according to both month (P = 0.015) and season (P = 0.048). Relapse commonly occurred in October, and variations in relapse were not significant either in month (P = 0.52) or season (P = 0.12). Upper respiratory inflammation was the main factor responsible for relapse.

CONCLUSION: Our results suggest that environmental factors associated with winter and spring seasonality may be responsible for triggering the clinical onset of UC in Japan.

Relationship between non-adherence to aminosalicylate medication and the risk of clinical relapse among Japanese patients with ulcerative colitis in clinical remission: a prospective cohort study

BACKGROUND

Thirty to forty-five percent of ulcerative colitis (UC) patients show non-adherence to aminosalicylates, and non-adherence has been reported to increase the risk of clinical relapse. Because Japan differs from Western countries in terms of health care and drugs administered, adherence to aminosalicylates in Japan may differ from that elsewhere. Therefore, we examined aminosalicylate adherence and its relationship to the risk of clinical relapse of UC in Japan.

METHODS

A 1-year, prospective cohort study was conducted in 104 outpatients with UC in remission who had taken aminosalicylates >6 months. Aminosalicylate adherence was evaluated using data from a self-administered questionnaire and medical records. Non-adherence was defined as taking <80 % of the prescribed dose of aminosalicylates. The primary outcome was the record of clinical relapse in medical charts.

RESULTS

Twenty-nine patients (27.9 %) were evaluated as showing non-adherence. Among all subjects, 24 patients (23.1 %) relapsed. The non-adherence group had a higher rate of 1-year relapse than did the adherence group (41.3 vs. 16.0 %). Multiple Cox regression analysis showed that non-adherence increased the risk of clinical relapse 2.3-fold (hazard ratio 2.3, 95 % confidence interval 1.004-5.24, p = 0.04).

CONCLUSIONS

Although the adherence rate in this study was slightly higher than that in previous studies, Japanese patients with UC who were not adherent to their medications had a twofold greater risk of relapse than those who were. These results indicate the importance of early identification of patients with non-adherence. A program to support medication taking behavior is needed to prevent UC relapse.

Importance of appropriate pharmaceutical management in pregnant women with ulcerative colitis

Background

Ulcerative colitis (UC) often occurs in women of childbearing age. Compared to Western countries, however, few studies have investigated the impact of UC on the progress of pregnancy in Asian populations.

Methods

We retrospectively examined 91 pregnancies in 64 patients with UC experienced at our hospital and related institutions from 1991 to 2011, focusing on the relationship between the progression of UC during pregnancy, progress of the pregnancy itself, and the treatment of UC.

Results

In 80 of 91 pregnancies the patient had already been diagnosed with UC at the time she became pregnant, of whom 31 (38.8%) experienced exacerbation during pregnancy. Regarding severity, moderate or severe active-stage disease during pregnancy was seen in 13.7% of those who had been in remission at the onset of pregnancy versus 58.6% of those who had been in the active stage at onset (OR 8.9: 95%CI 3.0~26.4; P<0.01). The incidence of miscarriage or abortion was 9.8% in pregnancies in which UC was in remission at onset versus 31% in those in which it was in the active stage at onset (OR 4.1: 95%CI 1.2~13.9; P=0.02). Among patients, 62.5% were receiving pharmaceutical treatment at onset of pregnancy. Exacerbation during pregnancy occurred in 26.5% of the group who continued to receive the same treatment during pregnancy versus 56.3% of those with a dose decrease or discontinuation after onset (OR 3.6: 95%CI 1.0~12.4; P=0.04).

Conclusions

UC patients wishing to conceive should do so when in remission and continue appropriate pharmaceutical treatment during pregnancy.

Geographical variability and environmental risk factors in inflammatory bowel disease

The changing epidemiology of inflammatory bowel disease (IBD) across time and geography suggests that environmental factors play a major role in modifying disease expression. Disease emergence in developing nations suggests that epidemiological evolution is related to westernisation of lifestyle and industrialisation. The strongest environmental associations identified are cigarette smoking and appendectomy, although neither alone explains the variation in incidence of IBD worldwide. Urbanisation of societies, associated with changes in diet, antibiotic use, hygiene status, microbial exposures and pollution have been implicated as potential environmental risk factors for IBD. Changes in socioeconomic status might occur differently in different geographical areas and populations and, consequently, it is important to consider the heterogeneity of risk factors applicable to the individual patient. Environmental risk factors of individual, familial, community-based, country-based and regionally based origin may all contribute to the pathogenesis of IBD. The geographical variation of IBD provides clues for researchers to investigate possible environmental aetiological factors. The present review aims to provide an update of the literature exploring geographical variability in IBD and to explore the environmental risk factors that may account for this variability.

Survey of inflammatory bowel diseases in India

INTRODUCTION

Inflammatory bowel disease (IBD), both ulcerative colitis (UC) and Crohn's disease (CD), once thought to be uncommon, is now seen commonly in India. The Indian Society of Gastroenterology (ISG) Task Force on IBD decided to collate data on the clinical spectrum of IBD currently prevailing in India.

METHODS

An open call to members of ISG was given through publication of a proforma questionnaire in the Indian Journal of Gastroenterology and the web portal of ISG. The proforma contained questions related with demographic features, family history, risk factors, clinical manifestations and characteristics, course of disease, and pattern of treatment of IBD.

RESULTS

Of 1,255 filled questionnaires received, 96 were rejected and 1,159 (92.3 %) were analyzed. This comprised data on 745 (64.3 %) patients with UC, 409 (35.3 %) with CD, and 5 with indeterminate colitis. The median duration of illness was longer in patients with CD (48 months) compared to those with UC (24 months) (p = 0.002). More than one half of patients (UC 51.6 %, CD 56.9 %) had one or more extraintestinal symptoms. A definite family history of IBD was present in 2.9 % (UC 2.3 % and CD 4.6 %; p = 0.12). The extent of disease in UC was pancolitis 42.8 %, left-sided colitis 38.8 %, and proctitis alone in 18.3 %. The extent of disease involvement in CD was both small and large intestine in 39.6 %, colon alone in 31.4 % and small intestine alone in 28.9 %. Stricturing and fistulizing disease were noted in 18.8 % and 4.4 % of patients with CD respectively. Chronic continuous and intermittent disease course were present in 35.5 % and 47.2 % of UC patients respectively, and in 23.1 % and 68.8 % of CD patients. Four percent of patients with UC had undergone colectomy, while 15.2 % of patients with CD underwent surgical intervention.

CONCLUSIONS

The present survey provides a reasonable picture of the demographic features and clinical manifestations of Indian patients with IBD, their risk factors, course of disease, and the treatment given to them.

Inflammatory bowel disease in Asia: a systematic review

The incidence and prevalence of inflammatory bowel diseases (IBD), Crohn's disease (CD) and ulcerative colitis (UC), are lower in Asia than in the West. However, across Asia the incidence and prevalence of IBD has increased rapidly over the last two to four decades. These changes may relate to increased contact with the West, westernization of diet, increasing antibiotics use, improved hygiene, vaccinations, or changes in the gut microbiota. Genetic factors also differ between Asians and the Caucasians. In Asia, UC is more prevalent than CD, although CD incidence is rapidly increasing in certain areas. There is a male predominance of CD in Asia, but a trend towards equal sex distribution for UC. IBD is diagnosed at a slightly older age than in the West, and there is rarely a second incidence peak as in the West. A positive family history is much less common than in the West, as are extra-intestinal disease manifestations. There are clear ethnic differences in incidence within countries in Asia, and an increased incidence in IBD in migrants from Asia to the West. Research in Asia, an area of rapidly changing IBD epidemiology, may lead to the discovery of critical etiologic factors that lead to the development of IBD.

Efficacy and safety of Fufangkushen colon-coated capsule in the treatment of ulcerative colitis compared with mesalazine: a double-blinded and randomized study

ETHNOPHARMACOLOGICAL RELEVANCE

Fufangkushen colon-coated capsule (FCC) was a newly developed herbal drug for treating ulcerative colitis (UC) patients with traditional Chinese medicine (TCM) pattern of damp-heat accumulating in the interior.

OBJECTIVE

To explore the efficacy and safety of FCC in the treatment of active UC compared with Huidi (HD, mesalazine enteric-coated tablets) were evaluated in a double-blinded and randomized clinical trial.

MATERIALS AND METHODS

In the double-blind, double-dummy, multicenter, randomized and controlled study, 320 active UC patients with TCM pattern of damp-heat accumulating in the interior were assigned to two groups: 240 treated with FCC plus HD placebo treatment, 80 with HD plus FCC placebo. The drugs and their corresponding placebos were administrated at advised dosage for 8 weeks. The primary endpoint was a positive clinical response at week 8, and Mayo scoring system was employed for assessment of UC activity.

RESULTS

At the 8th week, 72.50% of patients in FCC group (170 of 234) and 65.00% of patients in HD group (52 of 80) had achieved a clinical response. There was no statistically significance between the 2 groups (P>0.05). The proportions of patients who had a clinical remission was similar in 2 groups (41.50% in FCC group, 41.25% in HD group, P>0.05), mucosal healing rate at week 8 in the two groups were also without significant difference (55.13% in FCC group, 55.00% in HD group, P>0.05). Mayo scores at week 8 showed no statistically difference in the two groups. No significant differences were observed between the safety profiles of the 2 groups (P>0.05). No severe AEs were reported in either group. The latent class analysis indicated that FCC was superior applicable for the left hemicolon involved patients than HD.

CONCLUSIONS

Compared with HD, a mesalamine enteric-coated tablet, FCC is similarly effective and safe in the treatment of active UC with TCM pattern of damp-heat accumulation interior pattern. In addition, FCC indicates superior effect in the treatment of UC with inflamed area of the left hemicolon than HD.

Comparison of clinical characteristics and management of inflammatory bowel disease in Hong Kong versus Melbourne

BACKGROUND AND AIM

Inflammatory bowel disease (IBD), common in Melbourne, was rare but is now increasing in incidence in Hong Kong (HK). To investigate whether these are the same diseases in the West and East, potential causes of changing incidence, and to plan resource needs, an appreciation of clinical characteristics in contrasting populations is essential.

METHODS

Disease characteristics were collected from prospectively populated IBD databases in two specialist centers in Melbourne, Australia and HK.

RESULTS

Of 795 patients (Crohn's disease [CD] : ulcerative colitis [UC] Melbourne 272:159 and HK 161:203), the age of diagnosis was higher, there were proportionally more male patients with CD but no UC sex difference, fewer patients were current or ex-smokers (CD 8% vs 50%; UC 17% vs 35%) and a family history of IBD was less common (2% vs 11%; P < 0.001) in HK compared to Melbourne. Stricturing and perianal CD were more common in HK (12% vs 6%; P < 0.001; and 29% vs 16%; P = 0.001, respectively). In HK for UC, more patients had extensive disease at diagnosis (42% vs 22%) but colectomy was less common (7% vs 20%; P < 0.001). In Melbourne there was greater steroid use at diagnosis and patients were more likely to receive an immunomodulator or anti-tumor necrosis factor agent.

CONCLUSIONS

IBD in HK was diagnosed at an older age, and had more complicated disease behavior than in Melbourne. Medical therapy, however, was less intense in HK. These differences may relate to real differences in disease or delayed diagnosis due to late presentation and less disease recognition in HK.

Autoimmune pancreatitis: the clinicopathological characteristics of the subtype with granulocytic epithelial lesions

Autoimmune pancreatitis (AIP) has been established as a distinct form of chronic pancreatitis that is distinguishable from other types such as alcoholic, hereditary or obstructive chronic pancreatitis. AIP seems to be a global disease, since it has been reported in many different countries, especially from Japan, USA and Europe (Germany, Italy, United Kingdom). Typical histopathological findings in the pancreas in AIP include a periductal lymphoplasmacytic infiltration with fibrosis, causing narrowing of the involved ducts. The typical clinical features include presentation with obstructive jaundice/pancreatic mass and a dramatic response to steroids. However, while the reports from Japan describe uniform changes called lymphoplasmacytic sclerosing pancreatitis (LPSP) in the pancreas from AIP patients, the reports from Europe and USA distinguish two histopathologic patterns in AIP patients: one with the characteristics of LPSP and another with slightly different histological features, called idiopathic duct centric pancreatitis (IDCP) or AIP with granulocytic epithelial lesions (GELs). This article reviews the evidence that GEL-positive AIP or IDCP is a second type of AIP, distinct from LPSP, in regard to pancreatic pathology, immunology and epidemiology.

Inflammatory bowel disease in the Asia-Pacific area: a comparison with developed countries and regional differences

The Asia-Pacific region has been marked as an area with a low incidence of inflammatory bowel disease (IBD), although confusion always existed as to whether this low incidence was a result of low diagnostic awareness, a high incidence of infective diarrhoea and its diagnostic overlap or a true low incidence. As epidemiological studies from this region are being made available it is clear that the incidence and prevalence rates of IBD in Asia-Pacific region are low compared with Europe and North America. They are however, increasing rapidly. There are substantial variations in the incidence and prevalence rates of IBD in various ethnic groups in Asia. The highest incidence rates are recorded from India, Japan and the Middle East and there exists a genetic predisposition of South Asians (Indians, Pakistanis and Bangladeshis) to ulcerative colitis (UC). It appears that certain racial groups are more prone than others to develop IBD. For instance, Indians in South-East Asia have higher rates than Chinese and Malays. While there is a host genetic predisposition, environmental factor(s) may be responsible for this difference. The clinical phenotypes and complication rates of Asian IBD resemble those of the Caucasian population in general, but some heterogeneity is observed in different regions of Asia. There is no evidence of a north-south or an east-west divide in the Asia-Pacific region. The available studies suggest an increasing incidence of UC in the Asia-Pacific region and hence it is an appropriate time to launch well-designed epidemiological studies so that etiopathogenetic factors can be identified. There is a male predominance in Crohn's disease in the Asian population. The NOD2/CARD15 gene is not associated with CD in the Japanese, Korean, Chinese and Indian population.

The prevalence and clinical significance of perinuclear anti-neutrophil cytoplasmic antibody in Korean patients with ulcerative colitis

Perinuclear anti-neutrophil cytoplasmic antibody (pANCA) is a serological marker associated with various immune-mediated diseases whose clinical significance and possible diagnostic roles in ulcerative colitis (UC) are still unclear. We aimed to evaluate the prevalence of pANCA expression and its association with clinical findings and disease course in Korean patients with UC. This study included 484 patients with UC who were diagnosed and treated between 1990 and 2006 at Severance Hospital, Yonsei University, Seoul, Korea, and were followed for at least 1 year. Clinical findings at diagnosis, disease extent, treatment modalities used, and cumulative relapse rates were analyzed and compared to pANCA expression. Of the 484 patients, 405 (83.7%) were evaluated for pANCA and were eligible for analysis. The overall pANCA prevalence was 22.1%, with a female preponderance (male, 21.5%; female, 31.6%; P < 0.05). Proctitis was more common in pANCA-negative patients (pANCA-negative, 37.6%; pANCA-positive, 25.2%, P < 0.05). UC activity index and cumulative relapse rates were higher in pANCA-positive patients. However, there were no significant differences in the cumulative probability of steroid and immunosuppressant use and operation rate between the two groups. The prevalence of pANCA expression in Korean patients with UC was relatively low compared to that in Western countries. Although UC patients with pANCA expression had more severe clinical findings at diagnosis and higher cumulative relapse rates in our study, further prospective studies are warranted to clarify whether pANCA positivity influences the initial clinical presentation or disease aggressiveness.

The Asia-Pacific consensus on ulcerative colitis

Inflammatory bowel disease (IBD) is increasing in many parts of the Asia-Pacific region. There is a need to improve the awareness of IBD and develop diagnostic and management recommendations relevant to the region. This evidence-based consensus focuses on the definition, epidemiology and management of ulcerative colitis (UC) in Asia. A multi-disciplinary group developed the consensus statements, reviewed the relevant literature, and voted on them anonymously using the Delphi method. The finalized statements were reviewed to determine the level of consensus, evidence quality and strength of recommendation. Infectious colitis must be excluded prior to diagnosing UC. Typical histology and macroscopic extent of the disease seen in the West is found in the Asia-Pacific region. Ulcerative colitis is increasing in many parts of Asia with gender distribution and age of diagnosis similar to the West. Extra-intestinal manifestations including primary sclerosing cholangitis are rarer than in the West. Clinical stratification of disease severity guides management. In Japan, leukocytapheresis is a treatment option. Access to biologic agents remains limited due to high cost and concern over opportunistic infections. The high endemic rates of hepatitis B virus infection require stringent screening before initiating immune-suppressive agents. Vaccination and prophylactic therapies should be initiated on a case-by-case basis and in accordance with local practice. Colorectal cancer complicates chronic colitis. A recent increase in UC is reported in the Asia-Pacific region. These consensus statements aim to improve the recognition of UC and assist clinicians in its management with particular relevance to the region.

Asian perspectives in the management of inflammatory bowel disease: findings from a recent survey

BACKGROUND AND AIM

The prevalence and incidence of inflammatory bowel disease (IBD) differs worldwide. While the prevalence of IBD has stabilized in Europe, the USA and Japan, an increasing trend has been observed in Asia. However, there are no data on the current clinical practice for the management of IBD in the region. The present study aims to investigate the number of existing and new cases of IBD and to understand the current practice of diagnosis and treatment of IBD in different Asian countries.

METHODS

A self-administered questionnaire, designed according to European and US guidelines, was distributed to IBD specialists throughout Asia. The questionnaire estimated the annual incidence of existing and new IBD cases in physicians' clinical practices and evaluated their procedures of diagnosis and preference for therapeutic treatment and maintenance treatment.

RESULTS

Eighty-seven questionnaires were received out of the 107 distributed. In the clinical practices of these 87 respondents, there were 502 existing and 73 new cases per year for ulcerative colitis (UC) and 202 existing and 32 new cases per year for Crohn's disease (CD). Colonoscopy and histology were the most commonly used methods for the diagnosis of UC and CD, but clinical practice regarding the diagnosis of IBD varied. The treatment of choice for mild-to-moderate UC and CD was 5-aminosalicylic acid (5-ASA), which is also the preferred choice for the maintenance treatment of UC and CD.

CONCLUSION

Clinical practice with regards to IBD diagnosis and management varies within Asia.5-ASA is the preferred treatment and maintenance therapy for mild-to-moderate IBD.

Inflammatory Bowel Disease in the United States from 1998 to 2005: Has Infliximab Affected Surgical Rates?

The treatment costs for patients in the United States with inflammatory bowel disease (IBD) exceed 1.7 billion dollars/year. Infliximab, an antibody to tumor necrosis factor-α, has been extensively used to treat IBD, with 390,000 IBD patients receiving the drug since its FDA approval in 1998. We sought to determine the impact of infliximab on population-based rates of hospitalizations and surgical care for patients with IBD in the United States. We used data from the Nationwide Inpatient Sample to analyze patterns of hospital-based treatment provided to patients with IBD between 1998 and 2005. Data from this analysis were combined with census data to calculate trends in population-based rates of treatment. Overall rates of hospitalization for patients with Crohn's disease and ulcerative colitis increased significantly between 1998 and 2005 (5.1%/year and 3.4%/year respectively, P < 0.001 for each). During the same time period there were no changes in the overall rates of surgical care. The expanding use of infliximab has not significantly impacted the use of surgical procedures for patients with either ulcerative colitis or Crohn's disease, and rates of nonsurgical hospitalizations have actually increased. Even in the era of infliximab, surgical care remains a mainstay in the treatment of IBD.

Distribution and manifestations of inflammatory bowel disease in Asians, Hispanics, and African Americans: a systematic review

OBJECTIVES

Although inflammatory bowel disease (IBD) has been reported worldwide, most studies have focused on Caucasian populations. Our aim was to summarize the existing epidemiological literature, identify temporal trends, and highlight areas for future research.

METHODS

We carried out a systematic review following standard guidelines to evaluate the incidence, prevalence, temporal trends, disease characteristics, and extra-intestinal manifestations (EIMs) of IBD in African American, Hispanic, and Asian adult patients. Two investigators independently identified eligible studies through 2008 using structured keyword searches in PubMed, applied several inclusion and exclusion criteria, and abstracted the data.

RESULTS

Twenty-eight publications were included, encompassing 1,272 Hispanic, 547 African American, and 35,844 Asian patients with IBD. Greater proportions of Hispanic (36.7-84.3%) and Asian (30.6-74.7%) patients were diagnosed with ulcerative colitis (UC) than with Crohn's disease (CD) compared with African Americans (27.6-40.6%). The prevalence rates of IBD in Hispanics in Puerto Rico varied between 5 (rural) and 62 (urban) per 100,000. Crude prevalence rates in Asia varied between 6 (Singapore) and 136 (South Asians in UK) per 100,000 for UC, and between 3 (Singapore) and 33 (South Asians in UK) per 100,000 for CD. Three studies reported a rising annual incidence rate among Hispanics (from 2.6 to 7.5 per 100,000) and Asians (from 0.22 to 3.62 per 100,000). Fistulizing CD was reported in nearly one-third of Hispanic patients, up to one-quarter of African-American patients, and up to one-half of Asian patients. Ileocolonic disease was the most common site of CD among the three racial/ethnic groups, with skin and joint manifestations noted as the most common EIMs.

CONCLUSIONS

Prevalence and incidence rates in Hispanics and Asians have recently increased. There are many similarities and differences in disease location and behavior among racial/ethnic groups. There is a paucity of literature on all aspects of the disease in Hispanics, in the incidence and prevalence of IBD in African Americans, and in Asians with IBD outside Asia.

An update on the epidemiology of inflammatory bowel disease in Asia

A rising trend in the incidence and prevalence of inflammatory bowel disease (IBD) in Asia has been recognized for the past two decades. It has been postulated that this phenomenon may be related to the westernization of lifestyles, including changes in dietary habits and environmental changes such as improved sanitation and industrialization. Previously we reported that the incidence and prevalence rates of IBD in Asia were low compared with the West, but there was a notably rising secular trend. In this review, we summarize the recent epidemiological data in Asia, characterize the clinical features, risk factors and genetic susceptibility of Asian IBD patients, and compare these to those of Western IBD patients. In the past decade, the incidence and prevalence of IBD reported across Asia, particularly in East Asia, has continued to increase. Familial clustering is generally uncommon in East Asia but appears to be higher in West Asia. The genetic susceptibilities in Asian IBD patients differ from those of White patients, as NOD2/CARD15 mutations are much less common. The clinical phenotypes and complication rates of Asian IBD resemble the White population in general, but with some differences, including lower surgical rates, higher prevalence of males, and higher prevalence of ileocolonic involvement among East Asian Crohn's disease patients, and a low frequency of primary sclerosing cholangitis among IBD patients in East and Southeast Asia.

Epidemiology of inflammatory bowel disease in the Songpa-Kangdong district, Seoul, Korea, 1986-2005: a KASID study

BACKGROUND

Crohn's disease (CD) and ulcerative colitis (UC) are considered rare diseases in developing countries. We have evaluated the incidence and prevalence of CD and UC over time in a district of Seoul, Korea.

METHODS

A population-based study was performed from 1986 to 2005 in the Songpa-Kangdong district of Seoul. To recruit patients as completely as possible, multiple information sources, including all medical facilities in the study area and 3 referral centers nearby but outside the study area, were used.

RESULTS

During the 20-year study period, 138 incident cases of CD (102 men, 36 women) and 341 incident cases of UC (170 men, 171 women) were identified. For the 20-year period, the adjusted mean annual incidence rates of CD and UC per 100,000 inhabitants were 0.53 (95% CI 0.44-0.62) and 1.51 (95% CI 1.34-1.67), respectively. When analyzed by 5-year intervals, the mean annual incidence rates of CD and UC increased significantly, from 0.05 and 0.34 per 100,000 inhabitants, respectively, in 1986-1990 to 1.34 and 3.08 per 100,000 inhabitants, respectively, in 2001-2005. The adjusted prevalence rates of CD and UC per 100,000 inhabitants on December 31, 2005, were 11.24 (95% CI 9.29-13.18) and 30.87 (95% CI 27.47-34.27), respectively.

CONCLUSIONS

The incidence and prevalence of CD and UC in Seoul, Korea, are still low compared with those in Western countries, but are rapidly increasing.

Inflammatory bowel diseases in the elderly

Inflammatory bowel disease (IBD) in elderly individuals is associated with a unique set of challenges, some of which are related to age. This article examines the diagnosis and management of IBD in the context of recent advances in the understanding of its pathogenesis, and newer therapeutic modalities that have been possible from these advances.