The effect of pre-diagnostic vitamin D supplementation on cancer survival in women: a cohort study within the UK Clinical Practice Research Datalink

Table 1 Characteristics of women with specific cancers, identified through the General Practice Research Datalink (2002–2011)

	Breast		Colorectal		Lung		Gynaecological^a
	N = 11,112		N = 4122		N = 3352		N = 2979
	n	%	n	%	n	%	n	%
Supplementation
None	9952	89.6	3566	86.5	2793	83.3	2687	90.2
1–2 prescriptions	318	2.9	130	3.2	141	4.2	72	2.4
3+ prescriptions	842	7.6	426	10.3	418	12.5	220	7.4
Age group
<60	2019	18.2	324	7.9	249	7.4	484	16.3
60–64	2213	19.9	441	10.7	438	13.1	586	19.7
65–69	1888	17.0	564	13.7	516	15.4	557	18.7
70–74	1427	12.8	648	15.7	628	18.7	514	17.3
75–79	1339	12.1	761	18.5	651	19.4	360	12.1
80 and above	2226	20.0	1384	33.6	870	26.0	478	16.1
Period of diagnosis
2002–03	1809	16.3	587	14.2	453	13.5	438	14.7
2004–05	2582	23.2	920	22.3	736	22.0	670	22.5
2006–07	3182	28.6	1175	28.5	981	29.3	841	28.2
2008–09	3289	29.6	1308	31.7	1067	31.8	951	31.9
2010–11	250	2.3	132	3.2	115	3.4	79	2.7
Vital status at follow-up
Alive	9009	81.1	2396	58.1	596	17.8	1828	61.4
Dead	2103	18.9	1726	41.9	2756	82.2	1151	38.6
Smoking
Never	6793	61.1	2539	61.6	523	15.6	1936	65.0
Current	1426	12.8	444	10.8	1399	41.7	308	10.3
Ex	2559	23.0	1020	24.8	1383	41.3	654	22.0
Missing	334	3.0	119	2.9	47	1.4	81	2.7
Alcohol
None/ex	2569	23.1	1081	26.2	984	29.4	716	24.0
Any	7383	66.4	2533	61.5	1980	59.1	1930	64.8
Missing	1160	10.4	508	12.3	388	11.6	333	11.2
BMI^b
Underweight	155	1.4	118	2.9	221	6.6	41	1.4
Normal	3576	32.2	1451	35.2	1314	39.2	788	26.5
Overweight	3498	31.5	1227	29.8	883	26.3	877	29.4
Obese	2656	23.9	804	19.5	539	16.1	951	31.9
Missing	1227	11.0	522	12.7	395	11.8	322	10.8
Deprivation level^c
Quintile 1 (deprived)	913	8.2	391	9.5	508	15.2	270	9.1
Quintile 2	1064	9.6	411	10.0	362	10.8	268	9.0
Quintile 3	1152	10.4	383	9.3	255	7.6	305	10.2
Quintile 4	1181	10.6	403	9.8	204	6.1	319	10.7
Quintile 5 (affluent)	1217	11.0	369	9.0	204	6.1	313	10.5
Missing	5585	50.3	2165	52.5	1819	54.3	1504	50.5

^aGynaecological cancers included 1372 women with ovarian cancer, 1599 women with uterine cancer and 8 women with other unspecificed gynaecological cancers
^bUnderweight: <18.5 kg/m²; normal weight: 18.5 to <25 kg/m²; overweight 25 to <30 kg/m²; obese > =30 kg/m²
^cStudy-specific quintiles of the Index of Multiple Deprivation (IMD) score, based on patient’s address

ISSN: 1471-2407