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the study of crohn 's ( cd ) and ulcerative colitis ( uc ) has been focused on caucasians , as the incidence and diagnosis of inflammatory bowel disease ( ibd ) have been more evident in this population .
the rates of uc and cd are highest in northern climates , in urban regions , and in well - developed areas of the world such as north america and europe and lowest in southern climates and underdeveloped areas [ 14 ] .
the reported prevalence of ibd in adults in the united states ( us ) has ranged from 37 to 238 per 100,000 for uc and 26 to 201 per 100,000 for cd [ 4 , 5 ] .
incidence in north america , northern and western europe has stabilized , and low incidence areas are showing an increase .
reports of ibd from barbados and the french west indies in the caribbean illustrate these changes [ 6 , 7 ] .
there is an increasing recognition of ibd in the minority populations of the united states [ 716 ] , and several studies have described the epidemiology of ibd in these populations .
many of these studies have centered on blacks with ibd , while ibd in hispanics is less well defined .
the incidence and prevalence of ibd in puerto rico has been rising over the past decades [ 1719 ] . with the aim of further examining hispanics with ibd
, we describe the demographic and clinical characteristics of a large university - based registry of ibd in hispanics living in puerto rico .
the registry is a database of patients with uc and cd that collects demographic and medical information at the time of interview .
subjects with documented diagnosis of ibd by clinical , radiologic , endoscopic , and/or pathologic criteria are recruited from the ibd clinics , support group , and community practices and represent diverse areas of puerto rico .
after informed consent , data is collected through an interview by trained investigators and medical records review .
information collected includes age , gender , diagnosis , age at onset of symptoms , age at diagnosis , urban or rural living , place of birth and parentage , family history of ibd , smoking history , extraintestinal manifestations , extent of disease , medications , and surgery .
method of diagnosis , including endoscopic procedures , imaging , pathologic specimens , and surgical findings , is obtained from the treating physician 's and/or clinic medical record .
the registry has continuing institutional review board approval from the university of puerto rico medical sciences campus ( protocol no .
hispanic subjects were identified by having both parents of puerto rican , dominican , venezuelan , or cuban origin .
five subjects were excluded because of non - hispanic origins ( two from the united states , one from nevis , one from israel , and one with a german mother ) .
the vast majority of subjects ( 585 ) were born in puerto rico of puerto rican parents .
forty - four were born in the united states , three in the dominican republic , three in cuba , and one in venezuela . all entries from 1995 until 2009 were analyzed for demographics , family history , smoking history , disease extent , extraintestinal manifestations , and surgery .
disease duration at the time of inclusion in the registry was calculated from the time of symptom onset and from the time of diagnosis .
six hundred thirty - five hispanic patients , 299 ( 47.1% ) with uc and 336 ( 52.9% ) with cd , were included in the registry during the study period . the ages ranged from 10 to 85 years old , with the youngest recording age of diagnosis at 7 years old .  
table 1 shows the demographics , family history , and smoking history of the population included in this study .
patients with uc were older , predominantly female , and smoked less at the time of diagnosis , when compared to patients with cd .
mean age for uc patients was 40.3  15.6 with mean ages at onset of 31  14.4 and at diagnosis of 32.6  14.4 .
mean age for cd patients was 30.9  12.2 , with a mean age at onset of 24.7  11.7 and at diagnosis of 26.8  12.6 . for ulcerative colitis ,
interval from onset was 9.3 years and interval from diagnosis was 7.7 years . for crohn 's disease ,
more than half ( 56% ) of uc patients were females , whereas 59% of cd patients were males .
family history of ibd was present in 19.3% of uc and 17.5% of cd patients . in the cohort with uc ,
an additional 27 other relatives had uc and 4 had cd . for patients with cd , 17 first - degree relatives ( parents , siblings , or offspring )
twenty - six more remote relatives ( including grandparents , aunts / uncles , cousins and nephews / nieces ) had cd and 27 had uc . at the time of inclusion in the upr ibd registry , the disease extent in subjects with uc was as follows : 13% proctitis , 16.2% proctosigmoiditis , 21% left side colitis , and 49.6% pancolitis . in subjects with cd
, 54.4% had ileal disease , 47% had colon involvement , 15.6% had perianal disease , 6.7% had jejunal disease , and 1.1% had upper gastrointestinal tract involvement .
31.9% of uc and over half ( 51.2% ) of cd patients reported having surgery for ibd at the time of the interview .
the most common were the various arthropathies , similar in both uc and cd , followed by erythema nodosum , which was more frequent in cd ( 1.6% in uc versus 6.8% in cd , p < 0.002 ) .
osteoporosis was found more frequently in cd , though not statistically significant ( 14 of 20 cases ) .
incidence and prevalence studies for puerto rico have shown an increase in both ulcerative colitis and crohn 's disease since the late 1990s [ 1719 ] .
most of the published studies focus on incidence and prevalence with limited descriptions of clinical characteristics
. studies in which hispanics with ibd are compared with caucasians and other ethnic or racial populations are limited by the small number of hispanics included . a study of 148 patients with ibd seen from 1999 to 2003 compared 58 whites , 54 african americans , and 30 mexican americans .
family history was present in only 10% of mexican americans as compared to 33% of whites . in those with ulcerative colitis , no differences in treatment and surgery were found . in another study comparing the same three groups ( h , aa , w ) , there was no difference between african americans and mexican americans when separately compared to whites in terms of intestinal manifestations of cd and uc , respectively . among uc patients ,
whites had significantly higher incidence than mexican americans of joint symptoms ( p < 0.0001 ) and osteoporosis ( p = 0.001 ) .
all the mexican americans with uc who were tested had positive p - anca compared to only 40% of whites ( p = 0.033 ) .
proctitis alone occurred in 32% of whites , but only in 9% of mexican americans with uc ( p = 0.022 ) . in general , there were no significant differences in medical treatment , surgeries , or hospitalizations in the uc and in the cd groups .
in summary , mexican americans with ibd differed significantly from other ethnic groups in the distribution of ibd subtypes , family history , and serological markers . a recent large study from the united states involving 1,126 subjects with ibd , of which 830 were white , 169 were puerto rican hispanics , and 127 were african americans , reported that hispanics were at higher risk of developing perianal disease and erythema nodosum . among uc patients , hispanics had more proximal disease extent .
hispanics with cd , but not uc , had lower prevalence of family history of ibd than whites .
hispanics were more likely to have undergone bowel diversion for cd ( 22.4% versus 7.4% , p = 0.001 ) but had fewer total surgeries for abdominal cd than whites .
the number of surgeries for perianal cd was similar among all racial groups . at 5 years , the proportion of surgery - free cd patients was 68% for whites and 60% for hispanics .
the median survival time free from surgery was 9.8  yr for whites and 6.6  yr for hispanics , with no significant increased risk of cd - related surgery for hispanics compared to white subjects .
hispanics had a higher prevalence of surgery indicated for chronic refractory uc ( 85.7% versus 40.7% , p < 0.001 ) .
furthermore , hispanics had a considerably higher rate of colectomy for any indication ( chronic disease , dysplasia , or fulminant colitis ) than white subjects ( 32.3% versus 15.8% , p < 0.01 ) .
a comparison between our upr ibd registry and other hispanic populations including puerto rico , spain , portugal , huelva , spain , mexico , panam , and argentina   is shown in tables 3 ( cd ) and 4 ( uc ) .
it includes gender distribution , mean age , family history of ibd , and percent with extraintestinal manifestations .
the comparison is limited by a number of small studies , the data reported for each population , and the period included in the study . as ibd incidence is considered to be increasing in hispanics , earlier studies such as the one from argentina and panam may not be representative of actual population characteristics .
a systematic review of ibd in asians , hispanics , and african americans published in 2009 concludes that , although the incidence is rising in hispanics , the literature regarding ibd manifestations is very limited .
variation in findings between different hispanic groups may be a result of a changing epidemiology accompanying a rising incidence of ibd , with earlier studies being unable to detect an increase in family history or the true prevalence of extraintestinal manifestations , as well as an evolution in disease phenotype over time .
these may be related to study design , small numbers of hispanics in the studies , true genetic variation , and environmental influences .
the limited inclusion of minorities in research studies , partly due to the low incidence of ibd at the time , but also possibly secondary to underrecruitment , poor interest in participation and referral bias , may also affect the results .
more studies are needed for a better characterization and comparison of epidemiology and clinical presentation of ibd in hispanics .
this knowledge may impact the therapeutic approach to these patients as well as the development of health care strategies to improve access and outcomes .
a registry of patients with inflammatory bowel 
                 diseases , ulcerative colitis ( uc ) and crohn 's 
                 disease ( cd ) , was created at the university of 
                 puerto rico in 1995 . 
 subjects with a documented 
                 diagnosis of ibd by clinical , radiologic , 
                 endoscopic , and/or pathologic criteria were 
                 recruited from the ibd clinics , support groups , and 
                 community practices , and demographic and medical 
                 data was collected . 
 all entries from 1995 to 2009 
                 were analyzed for demographics , family history , 
                 disease extent , extraintestinal manifestations , 
                 surgery , and smoking history . 
 results were 
                 described using summary statistics . 
 635 hispanics 
                 living in puerto rico , 299 with uc and 336 with cd , 
                 were included . 
 mean ages were 40.3 for uc and 30.9 
                 for cd . 
 over half ( 56% ) of uc and 41% of 
                 cd were females . 
 family history was present in 
                 19.3% of uc and 17.5% of cd . 
 surgery for 
                 ibd had been performed in 31.9% of uc and 
                 51.2% of the cd patients . over one - fourth of 
                 the patients reported extraintestinal 
                 manifestations , most frequently arthropathies . 
 our 
                 findings contribute to the limited epidemiologic 
                 and clinical data on hispanics with ibd .