Table 1.

Association of classic KS (cKS) with demographics, known risk factors and types of soil.

Group or exposure	cKS Cases N	KSHV+ Controls	Odds Ratio*	95% Confidence interval	P-value
Matching factors
Sex
Males	89	86	1.12	0.64–1.97	0.69
Females	53	37	Reference
Age (years)
81+	32	29	0.63	0.29–1.35	0.43‡
75 to 80	47	32	0.97	0.48–1.97
68 to 74	34	32	0.68	0.31–1.48
<68	29	30	Reference
Soil types
Tephra in adulthood community
>21% of land area	6	7	0.63	0.18–2.19	0.24‡
≤21% of land area	4	8	0.43	0.11–1.69
None	131	106	Reference
Andosols in adulthood community
>5% of land area	15	18	0.48	0.20–1.13	0.19‡
≤5% of land area	21	13	1.47	0.63–3.43
None	105	90	Reference
Clay soils in adulthood community
>11% of land area	29	21	1.38	0.66–2.90	0.34‡
≤11% of land area	26	26	1.27	0.64–2.54
None	86	74	Reference
Luvisols in adulthood community
>11% of land area	39	13	2.72	1.12–6.60	0.02‡
≤11% of land area	30	30	1.39	0.70–2.76
None	72	78	Reference
Previously noted risk factors†
Education
1st–4th grade	44	62	0.37	0.20–0.68	0.001
5th grade or more	97	60	Reference
Cigarette smoking
Never	71	45	3.39	1.19–9.66	0.07‡
Former	61	57	2.01	0.81–5.01
Current	10	21	Reference
Diabetes
Yes	45	15	3.54	1.67–7.50	0.001
No	97	108	Reference
Took oral cortisone in the last 10 years
Yes	53	26	2.70	1.42–5.14	0.003
No	89	97	Reference
Stratification variables†
Worked with plants or soil
Yes	77	72	1.07	0.60–1.91	0.83
No	65	51	Reference
Barefoot during childhood
No	64	65	Reference
Yes	78	56	0.74	0.42–1.29	0.30
Frequency of bathing during adulthood
More than 3 per week	68	45	Reference
Three per week or less	74	78	0.68	0.36–1.26	0.22
Drank well or cistern water
Sometimes/never	35	30	Reference
Always/usually	107	93	1.04	0.53–2.02	0.91
Drank community or tap water
Sometimes/never	59	53	Reference
Always/usually	83	70	0.90	0.51–1.57	0.71

^*Odds ratios adjusted for sex and age group.

^†Odds ratios also adjusted for category of chromic luvisol in adulthood community

^‡P-value for trend