Staple Food Fortification with Folic Acid and Iron and Gastrointestinal Cancers: Critical Appraisal of Long-Term National Fortification

Figures & data

Table 1. Age-adjusted standard rates for gastrointestinal tract cancers before and after mandatory flour fortification with folic acid and iron, in East Azerbaijan, Iran.

		Before fortification			After fortification
Esophageal Ca (ICD 15)		2004	2005	2006	2007	2008	2009	2010	2011	2012	2013	2014	2015
Age 35–54 years	F	12.03	43.07	36.92	52.96	23.95	12.05	15.03	35.97	23.6	18.78	18.14	20.41
	M	11.41	34.7	21.99	19.08	17.22	15.69	15.62	13.62	14.83	13.41	9.62	13.57
Age 55–74 years	F	133.76	217.6	186.52	290.18	238.37	69.62	225.7	167.32	117.55	145.6	140.11	203.51
	M	68.84	27.02	80.92	98.93	85.76	90.86	81.65	88.71	47.57	47.46	61.37	52.16
Gastric Ca (ICD 16–17)		2004	2005	2006	2007	2008	2009	2010	2011	2012	2013	2014	2015
Age 35–54 years	F	21.49	19.43	17.55	20.60	14.76	30.2	7.73	10.21	18.89	23.43	10.49	20.72
	M	12.23	44.08	37.79	53.92	23.83	12.23	15.48	36.61	24.08	28.9	18.03	19.87
Age 55–74 years	F	151.59	77.41	69.14	94.22	76.94	225.3	73.30	51.22	47.35	122.74	55.97	105.26
	M	130.97	205.15	175.85	268.16	217.66	71.23	232.97	172.74	121.7	147.19	143.79	208.58
CRC (ICD 18–21)		2004	2005	2006	2007	2008	2009	2010	2011	2012	2013	2014	2015
Age 35–54 years	F	15.05	14.57	19.41	25.51	32.83	24.56	19.45	28.28	18.18	23.69	23.92	26.75
	M	15.53	20.78	22.21	33.17	26.39	24.95	16.04	20.16	25.17	24.01	25.52	32.13
Age 55–74 years	F	35.54	50.24	44.56	60.51	44.05	52.44	87.32	64.39	49.07	63.87	65.45	84.43
	M	36.16	40.72	50.73	83.04	90.37	66.47	95.12	76.31	65.33	91.27	87.04	114.08

The age-adjusted standard rates are reported per 100,000 inhabitants.

Abbreviations: Ca: cancer; CRC: colorectal cancer; F: female: ICD: international classification disease; M: male.

Table 2. Trends analysis and cumulative rate differences for gastrointestinal tract cancers from before and after mandatory flour fortification with folic acid and iron in East Azerbaijan, Iran.

Cancer site sex		AAPC^a	95% CI for trend	P for trend	Rate ratio^b	95% CI for rate ratio
Esophageal Ca (ICD 15)
Age 35–54 years	F	−7.0	−15.1 to 1.9	0.1	0.71	0.59 to 0.85
	M	−7.2	−11.7 to −2.1	0.0	0.60	0.48 to 0.75
Age 55–74 years	F	−3.0	−11.5 to 1.2	0.5	1.1	1.00 to 1.24
	M	−5.9	−9.9 to −1.7	0.0	0.79	0.66 to 0.93
Gastric Ca (ICD 16–17)
Age 35–54 years	F	−4.8	−13.7 to 5.0	0.3	0.44	0.36 to 0.56
	M	−7.3	−15.3 to 6.1	0.1	0.57	0.47 to 0.68
Age 55–74 years	F	−2.9	−11.9 to 7.0	0.5	0.76	0.68 to 0.86
	M	−8.1	−10.1 to 7.3	0.7	1.00	0.98 to 1.22
CRC (ICD 18–21)
Age 35–54 years	F	8.1	−4.8 to 8.8	0.6	2.07	1.79 to 2.49
	M	1.7	−3.7 to 7.1	0.5	1.59	1.33 to 1.89
Age 55–74 years	F	5.1	1.0 to 9.4	0.0	1.50	1.27 to 1.76
	M	11.6	0.1 to 24.5	0.0	2.51	2.13 to 2.95

^aAverage annual parentage of change in cancer rates.

^bP < 0.05 is regarded as significant. Before fortification = 2004–2006. After fortification = 2013–2015.

Abbreviations: AAPC: average annual parentage of change; Ca: cancer; CRC: colorectal cancer; F: female: ICD: international classification disease; M: male.