Prevalence of arrhythmia-associated gene mutations and risk of sudden cardiac death in the Finnish population

Figures & data

Figure 1. Prevalence and geographic clustering of the ten arrhythmia-associated mutations in Finland. A: Prevalence per 10,000 individuals and 95% confidence interval for each mutation in Finland. B: Division of Finland into four geographic regions. C: Prevalence and 95% confidence interval for each mutation in the different geographic regions shown in B.

Table I. Demographic characteristics of the study samples.

	Population cohorts				Autopsy studies
	FINRISK 1992	FINRISK 1997	FINRISK 2002	Health 2000^a	HSDS	TASTY
n	5,342	7,673	8,210	7,240	297	528
Age at baseline, years, mean ± SD	44.7 ± 11.4	48.7 ± 13.3	48.3 ± 13.1	55.6 ± 15.2	52.1 ± 9.5	63.2 ± 18.7
Male, n (%)	2,476 (46.3%)	3,806 (49.6%)	3,821 (46.5%)	3,234 (44.7%)	297 (100%)	330 (62.5%)
Follow-up time, years, mean ± SD^b	16.2 ± 2.4	11.2 ± 1.9	6.7 ± 0.6	7.5 ± 1.6	–	–
Person-years at risk^b	86,760	86,215	55,329	48,069	–	–
n of probable SCD^b	109	139	58	84	114	96
n of possible SCD^b	20	35	16	32	3	9
n of unlikely SCD^b	343	465	172	337	178	287
n with unknown cause of death^b	16	57	7	20	2	5

^aIncluding the Mini-Finland Health Survey.

^bExcluding subjects aged > 80 or < 25 years at baseline.

Table II. Prevalence and clinical information of mutation carriers.

	FINRISK and Health 2000 population cohorts (n = 28,465)					HSDS and TASTY (n = 825)
Mutation	n of carriers	Prevalence per 10,000 individuals (95% CI)	n with arrhythmia^a	n with heart failure^b	n of SCD cases	n of carriers	n of SCD cases
KCNQ1 G589D	28	9.9 (6.6–14.9)	0	1	0	0	–
KCNQ1 IVS7-2A> G	1	0.4 (0.05–2.6)	0	0	0	0	–
KCNH2 L552S	26	8.0 (5.1–12.6)	1	0	0	1	1
KCNH2 R176W	42	17.6 (12.4–24.8)	0	0	1	2	2
PKP2 Q59L	85	29.3 (22.2–38.6)	10	3	2	1	0
PKP2 Q62K	12	4.3 (2.3–8.1)	1	2	0	0	–
PKP2 N613K	0	–	–	–	–	0	–
DSG2 3059_3062delAGAG	5	2.7 (1.0–7.5)	0	0	0	0	–
DSP T1373A	10	3.8 (1.6–8.7)	1	0	0	1	0
RYR2 R3570W	7	2.6 (1.0–6.3)	1	1	1	0	–
Total	215^c	78.5 (66.8–92.3)	14	7	4	5	3

^aDiagnosis of arrhythmia (ICD-10 I47–I49, ICD-9 427, ICD-8 427.4–427.9) in the Hospital Discharge Registry or the Causes of Death Registry or special reimbursement right for arrhythmia medication (ICD-10 I47–I49).

^bDiagnosis of heart failure (ICD-10 I50, ICD-9 428, ICD-8 427.0–427.1) in the Hospital Discharge Registry or the Causes of Death Registry or special reimbursement right for heart failure medication (ICD-10 I11.0, I13, I50, I97.1, P29.0).

^cOne subject with both PKP2 Q59L and RYR2 R3570W.

CI = confidence interval; HSDS = Helsinki Sudden Death Study; SCD = sudden cardiac death; TASTY = Tampere Autopsy Study.

Figure 2. Birthplaces of all FINRISK 1992, 1997, 2002, and Health 2000 participants. The dots are randomly located within the municipality of birth of the participants.

Figure 3. Birthplaces of the carriers of the six selected mutations. A: KCNQ1 G589D; B: KCNH2 L552S; C: KCNH2 R176W; D: PKP2 Q59L; E: DSP T1373A; F: RYR2 R3570W. The asterisks are randomly located within the municipality of birth of each mutation carrier. The corresponding distribution of birthplaces of all participants is shown in Figure 2.