Table 1.

Baseline data of patients with atrial fibrillation and with or without levothyroxine treatment, and number of incident cases of dementia during follow-up

	Population		Dementia events		Without dementia		P value*
	No.	%	No	%	No	%
Total population	156,104		9054		147,050
Exposition							< 0.001
Levothyroxine treatment	12,978	8.3	878	9.7	12,100	8.2
No levothyroxine treatment	143,126	91.7	8176	90.3	134,950	91.8
Gender							< 0.001
Males	89,251	57.2	4486	49.5	84,765	57.6
Females	66,853	42.8	4568	50.5	62,285	42.4
Age (years)							< 0.001
45–64	26,919	17.2	209	2.3	26,710	18.2
65–84	91,732	58.8	6175	68.2	85,557	58.2
≥ 85	37,453	24.0	2670	29.5	34,783	23.7
Educational level							< 0.001
≤ 9	76,264	48.9	4719	52.1	71,545	48.7
10–12	36,017	23.1	2023	22.3	33,994	23.1
> 12	43,823	28.1	2312	25.5	41,511	28.2
Immigrant status							0.2674
Born in Sweden	140,224	89.8	8102	89.5	132,122	89.8
Foreign born	15,880	10.2	952	10.5	14,928	10.2
Marital status							< 0.001
Married	85,474	54.8	4322	47.7	81,152	55.2
Not married	70,630	45.2	4732	52.3	65,898	44.8
Neighborhood deprivation							< 0.001
Low	17,347	11.1	966	10.7	16,381	11.1
Middle	78,938	50.6	4306	47.6	74,632	50.8
High	18,670	12.0	1085	12.0	17,585	12.0
Unknown	41,149	26.4	2697	29.8	38,452	26.1
Hospital diagnosis
Hypertension	43,854	28.1	2592	28.6	41,262	28.1	0.2428
CHD	43,111	27.6	2646	29.2	40,465	27.5	< 0.001
Heart failure	40,502	25.9	2294	25.3	38,208	26.0	0.1734
Stroke	25,610	16.4	1808	20.0	23,802	16.2	< 0.001
Obesity	1454	0.9	31	0.3	1423	1.0	< 0.001
Diabetes	17,623	11.3	1012	11.2	16,611	11.3	0.7289
COPD	10,998	7.0	555	6.1	10,443	7.1	< 0.001
Depression	3505	2.2	314	3.5	3191	2.2	< 0.001
Anxiety	2172	1.4	148	1.6	2024	1.4	0.0418
Alcoholism and related disorders	2932	1.9	182	2.0	2750	1.9	0.3407

CHD coronary heart disease, COPD chronic obstructive pulmonary disease

*P value was calculated based on chi-square test