Table 1.

Incidence of the second of two chronic conditions (per 1000 person-years) in persons living in Olmsted County, Minnesota, by age, sex and ethnicity

Ethnicity age (years)	Men			Women
	Persons	Person-years	Incidence rate* (n)	Persons	Person-years	Incidence rate* (n)
All ethnic groups
0–19	18 879	140 653	6.5 (921)	18 024	134 725	8.5 (1151)
20–39	27 732	151 734	17.2 (2613)	28 571	158 252	25.1 (3972)
40–49	16 396	82 324	43.6 (3590)	16 713	85 660	45.8 (3920)
50–59	11 779	52 085	85.2 (4436)	12 398	55 270	84.6 (4674)
60–69	5218	19 653	139.4 (2739)	5603	21 246	135.3 (2874)
70–79	1775	5451	209.9 (1144)	2184	6660	202.0 (1345)
≥80	531	1589	260.0 (413)	1016	2887	277.1 (800)
0–64	50 648	439 254	29.7 (13 059)	51 056	447 399	34.2 (15 319)
≥65	3794	14 236	196.5 (2797)	4636	17 300	197.5 (3417)
All ages	52 479	453 489	35.0 (15 856)	53 582	464 699	40.3 (18 736)
Standardised†	–	–	35.5	–	–	38.8
Blacks
0–19	877	6411	5.5 (35)	749	5362	6.0 (32)
20–39	1099	6178	16.5 (102)	934	5647	23.0 (130)
40–49	429	1836	63.2 (116)	324	1392	61.8 (86)
50–59	180	683	105.3 (72)	139	513	121.0 (62)
60–69	60	223	134.8 (30)	47	150	193.2 (29)
70–79	18	71	140.1 (10)	23	60	200.4 (12)
≥80	4	11	274.0 (3)	3	5	580.3 (3)
0–64	1848	15 240	22.0 (335)	1563	13 010	25.5 (332)
≥65	48	173	190.8 (33)	37	118	185.7 (22)
All ages	1873	15 413	23.9 (368)	1587	13 128	27.0 (354)
Standardised†	–	–	38.9	–	–	48.5
Asians
0–19	818	6331	3.5 (22)	826	6299	5.6 (35)
20–39	1090	6372	15.1 (96)	1168	7167	14.6 (105)
40–49	534	2464	39.8 (98)	591	2869	33.8 (97)
50–59	339	1588	71.8 (114)	376	1687	79.4 (134)
60–69	159	592	120.0 (71)	185	570	161.3 (92)
70–79	51	163	140.8 (23)	74	177	271.6 (48)
≥80	21	60	216.6 (13)	40	92	358.1 (33)
0–64	1897	17 137	21.6 (370)	1997	18 399	23.3 (429)
≥65	114	433	154.7 (67)	159	463	248.4 (115)
All ages	1954	17 571	24.9 (437)	2105	18 862	28.8 (544)
Standardised†	–	–	29.5	–	–	34.9
Whites
0–19	14 956	119 686	6.8 (818)	14 414	114 906	9.0 (1032)
20–39	21 792	128 801	17.9 (2303)	23 214	135 903	26.5 (3599)
40–49	14 426	74 921	43.6 (3269)	15 088	79 123	46.1 (3646)
50–59	10 795	48 361	85.8 (4149)	11 520	51 901	84.8 (4399)
60–69	4823	18 362	140.4 (2578)	5221	20 075	134.7 (2704)
70–79	1653	5090	212.6 (1082)	2030	6301	200.9 (1266)
≥80	497	1495	262.8 (393)	953	2754	274.5 (756)
0–64	40 703	383 410	31.2 (11 952)	42 149	394 566	35.9 (14 170)
≥65	3517	13 306	198.4 (2640)	4317	16 398	197.1 (3232)
All ages	42 382	396 716	36.8 (14 592)	44 465	410 964	42.3 (17 402)
Standardised†	–	–	36.0	–	–	39.4

*Incidence rates are reported per 1000 person-years.

†Incidence rates were directly standardised to the total US population from the 2010 US Decennial Census after removing the number of people with prevalent multimorbidity (≥2 chronic conditions) as projected from our previous study (see online supplementary table SB).¹⁶