Prevalence of chronic obstructive pulmonary disease in rural women of Tamilnadu: implications for refining disease burden assessments attributable to household biomass combustion

Figures & data

Table 1. Descriptive characteristics and prevalence of COPD of the study population of Tiruvallur district, Tamilnadu

Variables		Frequency	Prevalence (%) with 95% CI
Overall		900	2.44 (1.43, 3.45)
Age	30–50	598	1.8 (0.73, 2.87)
	51–70	302	3.6 (1.49, 5.70)
Religion	Muslim/Christian	122	4.1 (0.55, 7.65)
	Hindu	778	2.1 (1.09, 3.12)
Marital status	Single/Widow	252	3.5 (1.23, 5.77)
	Married	648	2.0 (0.9, 3.08)
Literacy status	Literate	198	1.5 (−0.19, 3.19)
	Illiterate	702	2.7 (1.5, 3.9)
House type	Pucca/Semipucca^a	545	2.3 (1.04, 3.56)
	Kutcha^b	355	2.5 (0.87, 4.12)
Kitchen type	Outdoor	457	2.4 (0.97, 3.82)
	Indoor	443	2.5 (1.06, 3.93)
Fuel type	Clean	147	2.0 (−0.26, 4.26)
	Biomass	753	2.5 (1.38, 3.61)
Passive smoking	No	668	2.3 (1.16, 3.44)
	Yes	232	2.9 (0.74, 5.1)
Income	>25,000	173	3.4 (0.69, 6.1)
	<25,000	727	2.2 (1.13, 3.27)
Cooking duration	≤15 years	241	1.2 (−0.17, 2.57)
	>15 years	659	2.9 (1.62, 4.18)
	≤2 hours/day	330	1.5 (0.5, 2.5)
	> 2 hours/day	570	3.0 (1.16, 4.84)
Main occupation	Outdoor	444	2.25 (0.87, 3.63)
	Indoor	456	2.63 (1.16, 4.1)

^aPucca – house with cemented walls and roof; ^bKutcha – crude, imperfect, temporary house with walls and roof made of mud or thatch.

Table 2. Univariate OR and adjusted effects of type of cooking fuel and other variables on prevalence of chronic obstructive pulmonary disease

Study variables		Univariate OR with 95% CI	Adjusted OR with 95% CI
Age	30–50	2.02 (0.86, 4.71)	1.4 (0.49, 4.01)
	51–70
Religion	Muslim/Christian	0.52 (0.19, 1.44)	0.55 (0.19, 1.54)
	Hindu
Marital status	Single/Widow	0.55 (0.23, 1.31)	0.72 (0.27, 1.95)
	Married
Literacy status	Literate	0.55 (0.16, 1.89)	0.73 (0.2, 2.7)
	Illiterate
House type	Pucca/Semipucca^a	1.06 (0.45, 2.52)	1.01 (0.41, 2.49)
	Kutcha^b
Kitchen type	Outdoor	1.03 (0.44, 2.41)	1.1 (0.43, 2.8)
	Indoor
Fuel type	Clean	1.24 (0.36, 4.25)	1.43 (0.36, 5.73)
	Biomass
Passive smoking	No	1.08 (0.42, 2.8)	1.16 (0.44, 3.05)
	Yes
Income	>25,000	0.63 (0.24, 1.62)	0.52 (0.19, 1.47)
	<25,000
Cooking duration	≤15 years	2.36 (0.69, 8.03)	1.76 (0.45, 6.83)
	>15 years
	≤2 hours/day	2 (0.73, 5.47)	2.05 (0.73, 5.72)
	>2 hours/day
Main occupation	Outdoor	1.17 (0.5, 2.74)	1.02 (0.41, 2.54)
	Indoor

^aPucca – house with cemented walls and roof; ^bKutcha – crude, imperfect, temporary house with walls and roof made of mud or thatch.