Clinical risk factors for underlying gastrointestinal malignancy in iron deficiency anaemia–prospective validation of the IDIOM score

Figures & data

Table 1. Odds ratios (95% confidence intervals) for parsimonious multiple logistic regression models of the clinical variables associated with GI malignancy for the observation and validation cohorts (Poole Hospital 2004–2015)

Variable	Observation cohort n = 720	Validation cohort n = 643	Combined cohorts n = 1,363
Sex
Female	RC	RC	RC
Male	4.0 (2.3, 7.0)	1.9 (1.1, 3.3)	2.8 (1.9, 4.0)
Age
≤70	RC	RC	RC
>70	3.3 (1.7, 6.4)	1.6 (0.9, 2.9)	2.2 (1.4, 3.3)
Haemoglobin quartile^*
Q1	RC	RC	RC
Q2	1.6 (0.6, 4.3)	1.2 (0.5, 3.1)	1.4 (0.7, 2.8)
Q3	2.5 (1.1, 6.1)	2.5 (1.1, 6.1)	2.9 (1.6, 5.4)
Q4	5.3 (2.4, 11.7)	2.9 (1.2, 6.9)	3.8 (2.1, 7.0)
Pseudo R^2	18%	4%	8%

Note: RC-Reference category.

^* Haemoglobin quartiles (g/L) : Observation cohort-Q1: >111.4, Q2: 102.5–111.4, Q3: 91.5–102.4, Q4: <91.5, Validation cohort-Q1: >112.0, Q2: 103.1–112.0, Q3: 90.6–103.0, Q4: <90.6, Combined cohort-Q1: >112.0, Q2: 102.1–112.0, Q3: 90.1–102.0, Q4: <90.0.

Table 2. The percentage prevalence (with 95% CIs) of GI malignancy in 16 subgroups by sex, age and haemoglobin quartile of 1,363 subjects with IDA (Poole Hospital 2004–2015). Absolute numbers for each sub-group are shown immediately below.

Hb quartile : g/L	Female ≤70 years	Female >70 years	Male ≤70 years	Male >70 years
Q1: >112.0	0 (0, 6.4)	4.1 (0.7, 15.1)	2.5 (0.4, 9.7)	12.2 (6.8, 20.8)
	0/71	2/49	2/79	12/98
Q2: 102.1–112.0	0 (0, 4.0)	5.7 (2.7, 11.2)	7.3 (1.9, 21.0)	15.5 (8.3, 26.4)
	0/115	8/141	3/41	11/71
Q3: 90.1–102.0	5.6 (2.3, 12.3)	10.1 (5.9, 16.7)	22.2 (9.4, 42.7)	18.7 (10.9, 29.7)
	6/107	14/138	6/27	14/75
Q4: <90.1	7.1 (3.2, 14.6)	13.8 (8.7, 20.9)	18.1 (8.7, 33.2)	23.9 (14.9, 35.8)
	7/98	19/138	8/44	17/71

Figure 1. The percentage prevalence of GI malignancy in 16 subgroups by sex, age and haemoglobin quartile of 1,363 subjects with IDA (Poole General 2004–2015). Haemoglobin quartile ranges are as in Table 2.

Table 3. Univariate odds ratios (95% CIs) and significance levels for the associations between other clinical characteristics and GI malignancy in 315 subjects (Poole Hospital 2012–2015)

Variable		Percent (n) with GI malignancy	Odds ratio (95% CI)	p-value
MCV (fl)	Q1: >86.4	9% (7)	RC
	Q2: 80.3–86.4	4% (3)	0.4 (0.1, 1.6)	0.20
	Q3: 74.2–80.3	13% (10)	1.5 (0.6, 4.3)	0.41
	Q4: ≤74.1	14% (11)	1.6 (0.6, 4.5)	0.33
MCH (pg)	Q1: >27.5	8% (6)	RC
	Q2: 25.4–27.5	9% (7)	1.2 (0.4, 3.6)	0.79
	Q3: 22.8–25.3	8% (6)	1.0 (0.3, 3.3)	0.98
	Q4: ≤22.7	15% (12)	2.1 (0.7, 5.9)	0.16
ESR (mm/hr)	Q1: >54	10% (8)	1.4 (0.5, 4.3)	0.54
	Q2: 38–54	10% (8)	1.4 (0.5, 4.3)	0.54
	Q3: 22–37	11% (9)	1.6 (0.5, 4.7)	0.40
	Q4: ≤21	8% (6)	RC
Weight loss (>7lbs)	No	9% (22)	RC
	Yes	11% (9)	1.2 (0.5, 2.7)	0.66
Regular ASA/NSAID	No	12% (22)	RC
	Yes	7% (9)	0.6 (0.3, 1.3)	0.16
FH GI cancer	No	10% (27)	RC
	Yes	8% (4)	0.8 (0.3, 2.4)	0.67