Table 2

Population, samples, percentage rates and relative risks of potentially preventable complications in the over 50 age group from NSW public hospital episode data 2006–2007

Preventable complication	Patient population	Percentage of patient episodes with the complication†				Relative risk of dementia patients with the complication compared with non-dementia patients‡
		Medical		Surgical		Medical		Surgical
		Sample	Per cent	Sample	Per cent	Sample	RR (CI)	Sample	RR (CI)
Urinary tract infection	Dementia	36 075	13.4	4854	14.7	58 223§	1.79** (1.70 to 1.90)	7680	2.88** (2.45 to 3.40)
	Non-dementia	146 813	7.9	18 986	5.6
	All >50	182 888	9.0	23 840	7.4
Pressure ulcer	Dementia	25 832	5.9	4007	7.3	38 480	1.61** (1.46 to 1.77)	5904	1.84** (1.46 to 1.31)
	Non-dementia	89 074	3.8	13 493	4.1
	All >50	114 906	4.2	17 500	4.9
Pneumonia	Dementia	36 875	4.8	5106	6.8	59 523	1.37** (1.26 to 1.48)	8184	1.66** (1.36 to 2.02)
	Non-dementia	150 118	3.5	20 497	4.2
	All >50	186 993	3.8	25 603	4.7
Deep vein thrombosis	Dementia	39 104	0.8	5154	1.4	62 459	0.82* (0.69 to 0.97)	8245	1.14 (0.78 to 1.68)
	Non-dementia	155 882	1.0	20 609	1.2
	All >50	194 986	0.9	25 763	1.2
Gastrointestinal bleeding	Dementia	30 035	1.1	2702	3.8	50 246	1.01 (0.85 to 1.19)	5405	1.68* (1.22 to 2.31)
	Non-dementia	131 088	1.1	16 215	2.3
	All >50	161 123	1.1	18 917	2.5
Sepsis	dementia	25 365	1.9	4469	10.6	39 218	1.34* (1.15 to 1.57)	6595	1.25 (0.96 to 1.64)
	Non-dementia	94 631	1.4	15 100	3.1
	All >50	119 996	1.6	19 569	4.9
Shock and cardiac arrest	Dementia	31 021	0.6	2793	1.3	51 256	1.09 (0.86 to 1.37)	5521	0.93 (0.58 to 1.50)
	Non-dementia	132 194	0.5	16 431	1.3
	All >50	163 215	0.6	19 224	1.3
Delirium	Dementia	37 933	4.0	5155	4.4	61 307	2.83** (2.54 to 3.15)	8251	3.10** (2.31 to 4.15)
	Non-dementia	154 805	1.5	20 636	1.5
	All >50	192 738	2.0	25 791	2.1
Surgical wound infection§	Dementia	–	–	5158	0.1	–	–	8253	1.12 (0.48 to 2.63)
	Non-dementia	–	–	20 633	0.0
	All >50	–	–	25 791	0.0
Pulmonary failure§	Dementia	–	–	2870	2.0	–	–	5628	0.98 (0.81 to 1.19)
	Non-dementia	–	–	16 660	1.7
	All >50	–	–	19 530	1.7
Physiological/metabolic derangement§,¶	Dementia	–	–	2881	11.5	–	–	5644	1.87** (1.55 to 2.25)
	Non-dementia	–	–	16 699	6.5
	All >50	–	–	19 580	7.3
Failure to rescue††	Dementia	2597	28.2	561	22.3	3745	1.24* (1.02 to 1.33)	778	0.86 (0.61 to 1.20)
Failure to rescue††	Non-dementia	8336	24.1	1647	25.0
	All >50	10933	25.1	2208	24.3

*p<0.5.
**p<0.0001.
†Excluding precipitating pre-existing conditions for each complication.
‡Weighted 80–20% to compensate for 1 : 4 case–control ratio.
§These complications are only measured in a surgical population.
¶Physiological and/or metabolic derangement are serous fluid and electrolyte imbalances.
††Failure to rescue is death following sepsis, shock, gastrointestinal bleeding or pneumonia.
NSW, New South Wales; RR, relative risk.