Relationship between the duration of smoking and blood pressure in Han and ethnic minority populations: a cross-sectional study in China

Table 4 Models for the duration of smoking and systolic blood pressure in the minority population

Model	Estimate	95% CI	P
Linear model
Model 1
Duration of smoking	0.468	0.398, 0.537	< 0.001
Model 2
Duration of smoking	0.461	0.391, 0.531	< 0.001
Sex (male vs. female)	−8.390	−15.646, −1.134	0.023
Quit vs. never drink	− 1.153	−4.221, 1.915	0.461
Current vs. never drink	4.199	1.919, 6.480	< 0.001
BMI	0.225	0.001, 0.449	0.049
Moderate vs. light physical activity	−5.709	−8.487, −2.931	< 0.001
Heavy vs. light physical activity	0.583	−1.455, 2.620	0.575
Model 3
Duration of smoking	0.450	0.380, 0.520	< 0.001
Sex (male vs. female)	−8.576	−15.811, − 1.341	0.020
Quit vs. never drink	−1.219	−4.283, 1.845	0.435
Current vs. never drink	4.282	2.007, 6.558	< 0.001
BMI	0.198	−0.027, 0.423	0.085
Moderate vs. light physical activity	−5.303	−8.079, −2.527	< 0.001
Heavy vs. light physical activity	1.092	−0.970, 3.154	0.299
LDL-C	0.155	−0.922, 1.233	0.778
FPG	1.302	0.633, 1.972	< 0.001
Spline model
Model 4 ^a
Duration of smoking (linear)	0.259	0.081, 0.437	0.004
Duration of smoking (non-linear)	0.269	0.057, 0.481	0.013
Segmented model
Model 5^a
Threshold of duration of smoking	23.948	14.714, 33.183	–
Duration of smoking (shorter than 23.948 years)	0.252	0.036, 0.469	0.022
Duration of smoking (longer than 23.948 years)	0.610	0.467, 0.752	–

Abbreviations: CI Confidence interval, BMI Body mass index, LDL-C Low-density lipoprotein cholesterol, FPG Fasting plasma glucose
^a Crude model

ISSN: 1471-2458