. 2023 Mar 13;131(3):037008. doi: 10.1289/EHP10710

Table 3.

Association between air pollution score and incident rheumatoid arthritis (RA) among UK Biobank participants ( $N =$ 342,973; $n =$ 2,034 incident RA cases).

Air pollution score^a	Case/ $n$	HR (95% CI) of incident RA			$p_{Trend}$
Air pollution score^a	Case/ $n$	Model 1^b	Model 2^c	Model 3^d	$p_{Trend}$
Per standard deviation increment	—	1.12 (1.07, 1.16)	1.06 (1.01, 1.10)	1.06 (1.01, 1.10)
Q1	454/85,743	Ref	Ref	Ref	0.000053
Q2	490/85,743	1.09 (0.96, 1.24)	1.00 (0.89, 1.14)	1.00 (0.88, 1.14)
Q3	514/85,743	1.17 (1.03, 1.33)	1.01 (0.89, 1.15)	1.01 (0.89, 1.15)
Q4	576/85,744	1.34 (1.18, 1.51)	1.14 (1.00, 1.29)	1.14 (1.00, 1.29)

Note: —, not applicable; CI, confidence interval; HR, hazard ratio; Q, quartile; Ref, reference; SD, standard deviation.

^{^a}

Air pollution score ranges: quartile 1: (48.54–63.35); quartile 2: (63.36–69.94); quartile 3: (69.95–76.43); and quartile 4: (76.44–202.00). $Mean \pm SD$ of the air pollution score is $70.63 \pm 11.12$ .

^{^b}

Adjusted for age and sex.

^{^c}

Adjusted for age, sex, UK Biobank assessment center, household income, education level, smoking status, body mass index, alcohol consumption, sedentary time, physical activity duration, and healthy diet score.

^{^d}