Table 1

Baseline characteristics of Swedish adults aged 45–80 years without cardiovascular disease according to dog ownership status (national cohort, n=2 026 865) and (TwinGene, n=10 110, responses derived from Screening Across the Lifespan Twin study (1998–2002))

National CohortTwinGene
All n=2 026 865
(100%)
Non-dog owners n=1 731 183
(85.4%)
Dog owners** n=2 95 682
(14.6%)
Mixed pedigree† n=32 003
(1.6%)
‘Active dog breeds’†,*** n=65 686
(3.2%)
All n=10 110
(100%)
Non-dog owners n=9626
(95%)
Dog owners** n=484
(5%)
Mixed pedigree† n=141
(1.3%)
‘Active dog breeds’†,*** n=143
(1.4%)
Age: mean±SD*52.8 (8.7)53.3 (8.9)49.9 (7.3)49.2 (7.1)50.0 (7.3)63.6 (7.1)63.7 (7.1)62.0 (6.7)61.9 (6.3)62.7 (6.7)
Male981 094 (48.4)839 321 (48.5)141 773 (47.9)11 841 (37.0)27 961 (42.6)4189 (41.4)3986 (41.4)203 (41.9)60 (42.6)64 (44.8)
Marital status
 Married/cohabiting1 276 074 (63.0)1 044 915 (60.4)231 159 (78.2)18 991 (59.3)46 638 (71.0)8039 (79.5)7648 (79.5)391 (80.8)110 (78.0)112 (78.3)
 Never married287 589 (14.2)265 895 (15.4)21 694 (7.3)4265 (13.3)6377 (9.7)771 (7.6)734 (7.6)37 (7.6)13 (9.2)14 (9.8)
 Divorced352 209 (17.4)316 728 (18.3)35 481 (12.0)7522 (23.5)10 325 (15.7)855 (8.5)824 (8.6)31 (6.4)11 (7.8)8 (5.6)
 Widowed110 993 (5.5)103 645 (6.0)7348 (2.5)1225 (3.8)2346 (3.6)445 (4.4)420 (4.4)25 (5.2)7 (5.0)9 (6.3)
Type of family
 Children at home658 355 (32.4)521 224 (30.0)137 131 (46.3)14 079 (44.0)28 785 (43.8)1500 (14.8)1397 (14.5)103 (21.3)31 (22.0)27 (18.9)
 No children at home1 369 617 (67.6)1 210 920 (69.9)158 697 (53.7)17 924 (56.0)36 901 (56.2)8610 (85.2)8229 (85.5)381 (78.7)110 (78.0)116 (81.1)
Education
 Compulsory541 662 (26.7)473 952 (27.4)67 710 (22.9)8596 (26.9)13 207 (20.1)4069 (40.2)3880 (40.3)189 (39.0)56 (39.7)52 (36.4)
 Secondary891 458 (44.0)751 156 (43.4)140 302 (47.5)16 729 (52.3)29 352 (44.7)3107 (30.7)2958 (30.7)149 (30.8)46 (32.6)36 (25.2)
 University593 745 (29.3)506 075 (29.2)87 670 (29.7)6678 (20.9)23 127 (35.2)2934 (29.0)2788 (29.0)146 (30.2)39 (27.7)55 (38.5)
Income quintile
 1 (lowest quintile)405 929 (20.0)342 412 (19.8)63 517 (21.5)8222 (25.7)12 695 (19.3)
 2405 486 (20.0)348 254 (20.1)57 232 (19.4)7472 (23.3)12 461 (19.0)
 3405 173 (20.0)347 691 (20.1)57 482 (19.4)6801 (21.3)12 586 (19.2)
 4405 175 (20.0)346 350 (20.0)58 825 (19.9)5620 (17.6)13 364 (20.3)
 5 (highest quintile)405 102 (20.0)346 476 (20.0)58 626 (19.8)3888 (12.1)14 580 (22.2)
Country of birth
 Sweden1 805 438 (89.1)1 529 664 (88.4)275 774 (93.3)29 168 (91.1)62 160 (94.6)10 110 (100)9626 (100)484 (100)141 (100)143 (100)
 Other Nordic countries§92 043 (4.5)80 740 (4.7)11 303 (3.8)1650 (5.2)2083 (3.2)00000
 Non-Nordic countries129 384 (6.4)120 779 (7.0)8605 (2.9)1185 (3.7)1443 (2.2)00000
Population density: median (interquartile range) inhabitant per square kilometre72.6 (228.8)76.7 (315.3)49.2 (92.8)45.0 (87.7)56.8 (106.2)60.7 (111.1)60.7 (114.7)41.8 (72.9)40.1 (70.3)45.9 (68.5)
Region of residence
 Norrland269 897 (13.3)222 443 (12.8)47 454 (16.0)4791 (15.0)9476 (14.4)1621 (16.0)1518 (15.8)103 (21.3)32 (22.7)22 (15.4)
 Svealand771 742 (38.1)669 673 (38.7)102 069 (34.5)10 278 (32.1)23 451 (35.7)3391 (33.5)3240 (33.7)151 (31.2)41 (29.1)42 (29.4)
 Götaland985 226 (48.6)839 067 (48.5)146 159 (49.4)16 934 (52.9)32 759 (49.9)5098 (50.4)4868 (50.6)230 (47.5)68 (48.2)79 (55.2)
Exercise
 Little or none2139 (21.2)2064 (21.5)75 (15.5)29 (20.7)16 (11.2)
 Average2611 (25.9)2508 (26.2)103 (21.3)29 (20.7)27 (18.9)
 Above average5319 (52.8)5014 (52.3)305 (63.1)82 (58.6)100 (69.9)
Tobacco use¶
 No history of tobacco4314 (42.7)4155 (43.2)159 (32.9)42 (29.8)46 (32.2)
 Previous tobacco user4061 (40.2)3833 (39.8)228 (47.1)69 (48.9)68 (47.6)
 Current tobacco user1735 (17.2)1638 (17.0)97 (20.0)30 (21.3)29 (20.3)
  • *Age is given at baseline. Numbers and % of the respective cohort are reported unless stated otherwise.

  • **For descriptive purposes, dog owners here are individuals who had a registered dog at any time point during the study period, and for TwinGene taken as ownership at the clinical test date.

  • †Proportion of this breed group of all participants.

  • ‡Information on income not available for the TwinGene substudy in the Swedish Twin Register.

  • §Other Nordic countries include Norway, Denmark, Iceland, Finland, the territories of the Åland Islands and the Faroe Islands.

  • ¶Information on exercise levels and tobacco use was not available from the Register of the Total Population.

  • ***Active dog breeds’ which comprises all terriers, scent hounds, pointing dog and retriever dog breed groups.