The Danish Heart Failure Registry: A Validation Study of Content

Figures & data

Table 1 Patient Characteristics

Main Group	Performance Measures	Definition
Basic characteristics	Status of hospital contact	Inpatient or outpatient
	Date of admission/outpatient contact
	Date of discharge	Only hospitalized patients
	Status of discharge	Alive or dead
Prognostic factors	Acute myocardial infarction	Yes or no
	Stroke	Yes or no
	Diabetes	Yes or no
	COPD	Yes or no
	Hypertension	Yes or no
	Serum creatinine ≥ 150 µmol/L	Yes or no
	Alcohol intake	≤ 7/14 units per week, > 7/14 units per week or NA
	Smoking	Smoker, previous smoker, never smoker or NA
	Echocardiography	Yes, date, or no
Diagnostic test	LVEF value	LVEF <25%, 25% ≤ LVEF ≤ 35%, 35% < LVEF ≤ 40%, 40% < LVEF < 50%, ≥ 50%
Functional capacity	NYHA classification	NYHA functional classification I, II, III, IV or NA
Pharmacological therapy	Status of ACEI/ARB inhibitor treatment	Yes or no
	Initiation of ACEI/ARB inhibitor treatment	Yes, date, or no
	Status of beta-blocker treatment	Yes or no
	Initiation of beta-blocker inhibitor treatment	Yes, date, or no
	Status of MRA treatment	Yes or no
	Initiation of MRA inhibitor treatment	Yes, date, or no
Nonpharmacological treatment	Exercise training	Yes, date or no Hospital training or training in municipality
	Patient education	Yes, date, or no
Readmission	Acute readmission within 4 weeks	Yes, date, or no
Mortality	Death within one year	Alive or dead, according to the Danish Civil Registration System

Abbreviations: COPD, chronic obstructive pulmonary disease; ACEI, angiotensin-converting-enzyme inhibitors; ARB, angiotensin II receptor blockers; LVEF, left ventricular ejection fraction; MRA, mineralocorticoid receptor antagonist; NYHA, New York Heart Association.

Figure 1 Consort for the patient selection.

Figure 2 Distribution of Danish heart failure departments included in the validation (green dot = participating; black dot = not participating).

Table 2 Baseline Characteristics for Patients Included (N= 453)

Characteristics	N (%)
Gender
Male	295 (65.1)
Female	158 (34.9)
Age (years)
18–64 years	157 (34.7)
65–80 years	195 (43.0)
≥ 80 years	101 (22.3)
Prognostic factors
Acute myocardial infarction	156 (34.4)
Stroke	57 (12.6)
Diabetes	101 (22.3)
COPD	79 (17.4)
Hypertension	202 (44.6)
Serum creatinine ≥ 150 μmol/L	52 (11.5)
Alcohol
≤ 7/14 units per week	386 (85.2)
> 7/14 units per week	27 (6.0)
Unknown	40 (8.8)
Smoking
Smoker	106 (23.4)
Former smoker	208 (45.9)
Never smoker	117 (25.8)
Unknown	22 (4.9)
Echocardiography
LVEF <25%	106 (23.4)
25% ≤ LVEF ≤ 35%	201 (44.4)
35% < LVEF ≤ 40%	91 (20.1)
40% < LVEF < 50%	20 (4.4)
≥ 50%	33 (7.3)
Missing	2 (0.4)
NYHA Classification
NYHA I	62 (13.7)
NYHA II	255 (56.3)
NYHA III	111 (24.5)
NYHA IV	7 (1.5)
Unknown	18 (4.0)
Pharmacological treatment
ACEI/ARB inhibitor prior HF diagnosis	272 (60.0)
ACEI/ARB inhibitor initiation within 8 weeks*	160 (35.3)
Beta-blockers prior HF diagnosis	232 (51.2)
Beta-blockers initiated within 12 weeks*	187 (42.3)
MRA prior HF diagnosis	56 (12.4)
MRA initiated within 12 weeks*	160 (35.3)
Non-pharmacological treatment
Exercise training, hospital	65 (14.3)
Exercise training, municipality	81 (17.9)
Patient education	411 (90.7)
Acute readmission
4-week rate of readmission	54 (11.9)

Note: *within time period after first contact.

Abbreviations: COPD, chronic obstructive pulmonary disease; LVEF, left ventricular ejection fraction; NYHA, New York Heart Association; ACEI, angiotensin converting enzyme inhibitors; ARB, angiotensin II receptor blockers; HF, heart failure; MRA, mineralocorticoid receptor antagonist.

Table 3 Sensitivity, Specificity and Predictive Values for Comorbidities

	N	DHFR	Medical Records		Sensitivity % (95% CI)	PPV, % (95% CI)	Specificity % (95% CI)	NPV, % (95% CI)
			Yes	No
AMI	453	Yes	149	7	87.1 (81.2–91.8)	95.5 (91.1–97.8)	97.5 (95.0–99.0)	92.6 (89.4–94.9)
		No	22	275
Stroke	453	Yes	53	4	82.8 (71.3–91.1)	93.0 (83.2–97.3)	99.0 (97.4–99.7)	97.2 (95.3–98.4)
		No	11	385
COPD	453	Yes	63	16	81.8 (71.4–89.7)	95.7 (93.2–97.6)	79.8 (70.7–96.6)	96.3 (94.1–97.6)
		No	14	360
Diabetes	453	Yes	99	2	95.2 (89.1–98.4)	98.0 (92.6–99.5)	99.4 (97.6–99.9)	98.6 (96.7–99.4)
		No	5	347
Hypertension	453	Yes	200	1	81.0 (75.5–85.7)	99.5 (96.6–99.9)	99.5 (97.3–100.0)	81.4 (77.1–85.0)
		No	47	205
S-creatinine >150 umol/L	453	Yes	45	3	91.8 (80.4–97.7)	93.8 (82.9–97.9)	99.2 (97.8–99.8)	99.0 (97.5–99.6)
		No	4	392

Abbreviations: DHFR, Danish Heart Failure Registry; CI, confidence Intervals; PPV, positive predictive value; NPV. negative predictive value; AMI, acute myocardial infarction; COPD, chronic obstructive pulmonary disease.

Table 4 Sensitivity, Specificity and Predictive Values for Smoking Status and Alcohol Consumption

	N	DHFR	Medical Records		Sensitivity, % (95% CI)	PPV, % (95% CI)	Specificity, % (95% CI)	NPV, % (95% CI)
			Yes	No
Never smoker	453	Yes	99	18	87.6 (80.1–93.1)	84.6 (76.8–90.6)	94.7 (91.8–96.8)	95.8 (93.1–97.7)
		No	14	322
Current smoker	453	Yes	102	4	76.1 (68–83.1)	96.2 (90.6–98.6)	98.8 (96.8–98.7)	90.8 (87.2–93.6)
		No	32	315
Former smoker	453	Yes	158	50	91.9 (86.7–95.5)	76.0 (69.6–81.6)	82.2 (77.2–86.5)	94.3 (90.6–96.8)
		No	14	231
< 7/14 alcohol units/week	451	Yes	320	64	92.8 (89.5–95.3)	83.3 (79.2–86.9)	39.6 (30.3–49.6)	62.7 (59–74.2)
		No	25	42
> 7/14 alcohol units/week	451	Yes	17	10	47.2 (30.4–64.5)	63.0 (42.4–80.6)	97.6 (95.6–98.8)	95.5 (93.1–97.3)
		No	19	405

Abbreviations: DHFR, Danish Heart Failure Registry; PPV, positive predictive value; NPV, negative predictive value.

Table 5 Sensitivity, Specificity and Predictive Values for Echocardiography, NYHA Classification, Medical Treatment, Patient Education, Physical Exercise and Readmission

	N	DHFR	Medical Records		Sensitivity, % (95% CI)	PPV, % (95% CI))	Specificity, % (95% CI)	NPV, % (95% CI)
			Yes	No
Echocardiography	453	Yes	449	2	99.8 (98.8–100.0)	99.6 (99.0–99.8)	33.3 (0.8–90.6)	50.0 (7.4–92.6)
		No	1	1
NYHA assessment within 3 months	453	Yes	402	33	99.8 (98.6–99.9)	92.4 (909–93.7)	34.0 (21.2–48.8)	94.4 (69.8–99.2)
		No	1	17
ACE/ATII inhibitors before HF diagnosis	453	Yes	243	29	96.8 (93.8–98.6)	89.3 (85–92.2)	85.6 (80.0–90.2)	95.6 (91.6–97.7)
		No	8	173
ACE-/ATII inhibitors started within 8 weeks	173	Yes	142	9	98.6 (95.1–99.8)	94.0 (90.2–96.5)	69.0 (49.2–84.7)	90.9 (71.2–97.6)
		No	2	20
Betablockers before HF diagnosis	453	Yes	203	29	90.2 (85.6–93.8)	87.5 (83.3–90.8)	87.3 (82.3–91.3)	90.1 (85.8–93.1)
		No	22	199
Betablockers started within 12 weeks of HF diagnosis	199	Yes	151	15	98.1 (94.4–99.6)	90.9 (86.9–93.8)	66.7 (51.1–80.0)	90.9 (79.2–98.9)
		No	3	30
MRA before HF diagnosis	453	Yes	48	8	77.4 (65.0–87.1)	85.7 (74.9–92.4)	98.0 (65.0–87.1)	96.5 (94.5–97.8)
		No	14	383
MRA started within 12 weeks of HF diagnosis	380	Yes	110	38	94.8 (89.1–98.1)	84.0 (77.6–88.8)	91.5 (87.3–94.7)	97.4 (94.5–98.8)
		No	6	226
Patient education	453	Yes	390	21	98.0 (96.1–99.1)	94.9 (93.0–96.3)	61.8 (47.7–74.6)	81.0 (67.5–89.7)
		No	8	34
Physical exercise	453	Yes	168	58	77.8 (71.6–83.1)	74.2 (69.6–78.6)	75.5 (69.5–80.9)	78.9 (74.2–82.9)
		No	48	179
Readmission within 4 weeks	452	Yes	34	19	65.4 (50.9–78.0)	65.2 (52.5–74.3)	95.3 (92.7–97.1)	95.5 (93.6–96.9)
		No	18	381

Abbreviations: DHFR, Danish Heart Failure Registry; PPV, positive predictive value; NPV, negative predictive value; NYHA, New York Heart Association Classification; ACE, angiotensin converting enzyme; ATII, angiotensin II; HF, heart failure; MRA, mineralocorticoid receptor antagonist.