Inflammatory bowel disease in India - Past, present and future

Table 1 Environmental factors involved in inflammatory bowel disease causation in India

Study type (region)	Sample size	Factors significant on univariate analysis				Factors significant on multivariate analysis, OR (CI)	Factors not significant
		Ulcerative Colitis		Crohn’s disease
		Favours	Protects	Favours	Protects
Case control[65] (south)1	200/200			Urban residence (birth/current)	Cattle in house compound (current)	Cattle in house compound (current) 0.57 (0.35-0.92)	Age, closed toilet in house, tooth cleanser use, pets in house (childhood/current), Cattle in house compound (childhood), appendicectomy, smoking, regular meat consumption
				Treated drinking water (childhood/current)	Regular fish consumption (> 1/wk)	Regular fish consumption (> 1/wk) 0.52 (0.33-0.80)
				Piped water supply in house (childhood/current)		Treated drinking water (childhood/current) 1.59 (1.02-2.47)
				Lactovegetarian
				High socioeconomic score
Case control[66] (north)1	513/188	Higher education (graduation and beyond)	Using private bed			Using private bed 0.25 (0.16-0.39)	Age, smoking, water source (municipal vs tubewell), illness in family, number of sibs
			Hand washing			Owning a pet 2.02 (1.14-3.59)
		Having personal towel	RCA/flush type latrine			RCA latrine 0.29 (0.14-0.60)
		Owning a pet				Flush type latrine 0.43 (0.23-0.82)
		Death in family				Death in family 2.19 (1.58-4.07)
Case control[67] (east)	50/50	Higher intake of refined sugarLow intake of fruits				Higher intake of refined sugar 1.78 (1.03-6.9)	Age, Sex, socioeconomic status, regular smoking and alcohol intake, rice, wheat, meat, fish, fried food, tea/coffee, green leafy vegetables2
						Low intake of fruits 0.28 (0.15-0.65)

¹More females had disease than controls;

²Higher intake of green leafy vegetables (P = 0.05) tended towards protective association.

Table 2 Comparative clinical features of inflammatory bowel disease in different countries

Country	India[9]		South East Asia[81,82]		Australia[81,82]
Factors	UC	CD	UC	CD	UC	CD
Median Age (yr)	38.5	35.9	42	34	42	34
Sex (M: F)	1.4:1	1.3:1	1.4:1	1.6:1	1:1.2	1:1.1
Smokers	21.3%	24.2%	6%	11%	8%	10%
Disease location
L1		28.9%		31%		31%
L2		31.4%		24%		24%
L3		39.6%		45%		45%
L4		5.8%		5%		5%
Disease behaviour
B1		76.8%		66%		88%
B2		18.8%		17%		10%
B3		4.4%		19%		2%
Perianal		6.9%		18%		12%
Disease extent
Proctitis	18.3%		37%		32%
Distal colitis	38.8%		32%		27%
Extensive colitis	42.8%		31%		41%
Treatment
5ASA	89.7%	58.4%	68%	49%	86%	71%
Corticosteroids	29.1%	26.9%	21%	42%	50%	67%
Immunosuppressive	29.8%	62.9%	8%	35%	0	14%
Biologics	0	2.2%	1%	5%	0	0
Antibiotic	0	0	25%	19%	0	21%
Probiotics	6.1%	7.6%
Surgery	4.0%	15.2%	1.6%	11.6%	5.9%	14.3%
Positive family history (%)	2.3%	4.6%	31%		17%1
EIM
Joints	33.3%	26.3%	13%1		3.6%1
Backache	31.5%	36.4%	3.3[AS]1
Skin	2.4%	3.4%	4.8%1		3.6%1
Incidence per 105 population	6.07%[8]		0.76%	0.54%	7.33%	14%

¹Present in overall inflammatory bowel disease population. EIM: Extraintestinal manifestations; AS: Ankylosing spondylitis; UC: Ulcerative colitis; CD: Crohn’s disease.

Table 3 Comparative data on ulcerative colitis related colorectal cancer in different Indian series

Study type	Incidence of CRC	Time duration of FU in years	Presented with CRC	CRC developed at FU	Risk of CRC at time in years	Risk Factors	LGD	HGD	Detected on surveillance/symptoms
Retrospective[91]	8/436 (1.8%)	12.1 (7-25)	4	4 (2/4 after 7, 8 yr of FU)		Pancolitis 6/8 (66.7%)	NM	NM	Symptoms
Retrospective[90]	5/532 (0.94%)	25	0	5 (in FU of 6 yr)	0 at 10, 2.3% (4.4% for pancolitis) at 20, 5.8% (10.2% for pancolitis) at > 20	Pancolitis, disease duration > 10 yr	2 progressed to CRC (1 after 5 yr, 1 at a different site after 1 yr). 6 did not progress in 1- 2 1/2 yr	2 (1 CRC after 3 yr, another operated immediately)	2 CRC on routine surveillance
Partly Retrospective, partly prospective[1]	5/50 (10%), [0/21 (prospective), 5/19 (retrospective)]	9.35 (1-30), prospective 4.5 (1-12), retrospective 15 (8-30)	0	5 (1 after 10 yr, 4 after 20 yr)	0 at 10, 1% at 20, 7% at > 20	Disease duration > 10 yr	No surveillance	No surveillance	5 at symptoms
Prospective[93]	12/430 (2.8%)	Median 6 (1-39)	0	After median 18 yr from onset (6-27), 3 at 6, 6, 7 yr FU	Incidence density per 103 PYD was 2.3 at 10, 3.3 at 20 , 7 at > 20	Pancolitis, longer disease duration	NM	NM	1 on surveillance after 11 yr/11 at symptoms, (unifocal in 10 and multifocal in 2)
Prospective surveillance study[92]	1/29 (3.4%)	10 (7.5-14.5)	0	1 (after 1 yr)		Pancolitis in 55%	5 at baseline, 3 new cases on surveillance	3 (1 CRC after 1 yr)	1 over 42 mo surveillance

CRC: Colorectal cancer; FU: Follow up; LGD: Low grade dysplasia; HGD: High grade dysplasia; PYD: Person years of disease duration; NM: Not mentioned.