Risk of classic Kaposi sarcoma with exposures to plants and soils in Sicily

Table 2 Three multinomial logistic regression models for association of classic Kaposi sarcoma (cKS) and KS-associated herpesvirus with aggregate exposures to plants, adjusted for core-model variables.*

	cKS cases				KSHV-negative controls				KSHV + controls*
Variables	N	OR*	95% CI	P	N	OR*	95% CI	P	N
*Cumulative plant exposure model*
Lifetime contacts with 20 plants¶
> 1262	19	0.93	0.35 - 2.44		201	1.73	0.78 - 3.83		16
281 - 1262	34	1.16	0.47 - 2.85	0.87†	189	1.16	0.54 - 2.50	0.04†	24
69 - 280	40	0.97	0.40 - 2.32		183	0.58	0.27 - 1.22		28
0 - 68	29	Ref			179	Ref			20
*Plant cluster model*
Cluster C‡	4	0.72	0.19 - 2.80	0.64	41	1.17	0.42 - 3.28	0.76	6
Cluster B	21	2.1	0.83 - 5.29	0.11	153	3.01	1.31 - 6.92	0.01	10
Cluster A	97	Ref			558	Ref			72
*Plant factor model*
Asteraceae factor
> median	56	1.12	0.58 - 2.19	0.73	390	1.19	0.68 - 2.07	0.55	43
≤ median	66	Ref			362	Ref			45
Euphorbia/Datura/Agave factor
> median	59	0.77	0.40 - 1.50	0.44	378	0.66	0.37 - 1.17	0.15	49
≤ median	63	Ref			374	Ref			39
Hypericum factor
> median	65	0.92	0.46 - 1.84	0.81	366	0.87	0.47 - 1.58	0.64	42
≤ median	57	Ref			386	Ref			46
Food/beverage/gladiolus factor
> median	61	1.23	0.58 - 2.60	0.58	395	1.51	0.79 - 2.89	0.21	40
≤ median	61	Ref			357	Ref			48

* Odds ratios (OR) and confidence intervals (CI), with KSHV+ controls as referent group, are adjusted for the variables in each model, as well as those in the "core model" (Table 1).
¶ The 20 plants were: Agave americana (Agavaceae), Acanthus mollis (Acanthaceae), Ceratonia siliqua (Fabaceae), Chrozophora tinctoria (Euphorbiaceae), Cichorium intybus (Asteraceae), Datura stramonium (Solanaceae), Dittrichia (formerly Inula) viscosa (Asteraceae), Euphorbia characias (Euphorbiaceae), Euphorbia dendroides (Euphorbiaceae), Euphorbia rigida (Euphorbiaceae), Gladiolus communis o italicus (Iridaceae), Hieracium (Asteraceae), Hypericum hircinum (Clusiaceae), Hypericum perforatum guttiferae (Clusiaceae), Iris sisyrinchium (Iridaceae), Lupinus albus (Fabaceae), Matricaria chamomilla compositae (Asteraceae), Picris echioides (Asteraceae), Taraxacum officinale (Asteraceae), and Trigonella foenum-graecum (Fabraceae).
† P_trend values.
‡ Cluster C is numerous plant contacts including Hypericum and Euphorbia. Cluster B is numerous plant contacts other than Hypericum and Euphorbia. Cluster A is relatively few plant contacts.

ISSN: 1750-9378