Table 4.

Association analysis between selected sociodemographic, water arsenic level metric variables and DM type 2 risk in unmatched and matched case–control studies

Variables	Case-unmatched control groups				Case-matched control groups
	OR	p-value	95% CI		OR	p-value	95% CI
			Lower	Upper			Lower	Upper
Selected sociodemographic variables
Age as of year 2008a	1.030	0.008	1.008	1.053	–	–	–	–
BMI in year 2008	1.203	<0.001	1.124	1.288	1.290	<0.001	1.135	1.466
Exercise	2.270	0.214	0.548	9.403	2.728	0.196	0.552	13.48
Having history of illness in parentsa	2.201	0.049	1.004	4.822	–	–	–	–
Having history of illness in siblings	2.955	0.011	1.312	6.656	6.560	0.005	1.813	23.73
Ever smokingb	–	–	–	–	4.648	0.204	0.344	62.76
Ever drinking	3.327	0.032	1.134	9.760	5.230	0.198	0.328	83.43
Govtb	–	–	–	–	0.375	0.144	0.100	1.398
Motorcar ownership	0.309	0.120	0.064	1.493	0.183	0.015	0.048	0.699
Arsenic level of water used for consumption in year 2000 variables
Drinking	3.220	0.890	0.000	3.2×108	7.541	0.824	0.000	5.9×108
Cooking	1.049	0.960	0.150	7.339	1.221	0.884	0.075	19.99
Teeth brushing	0.840	0.777	0.221	3.192	0.975	0.972	0.218	4.358
Arsenic level of water used for consumption in year 2008 variables
Drinking	1.482	0.889	0.005	406	4.304	0.730	0.001	2.0×104
Cooking	0.043	0.202	0.000	5.483	0.209	0.768	0.000	1.7×104
Teeth brushing	0.626	0.805	0.011	34.95	0.499	0.758	0.003	71.63

Notes:

^aOnly unmatched.

^bOnly matched. - means result is not available because the variable was not included in the analysis model; for government employers or business owner variable, laborers/others was used as reference.

Abbreviations: DM, diabetes mellitus; OR, odds ratio; CI, confidence interval; BMI, body mass index; Govt, government officers or business owners.