Walking activity during ambulant cardiac rehabilitation is related to maximum working capacity, age, and smoking behavior

Figures & data

Table 1 Patient group description (variable means together with their empirical SDs)

	n	Steps/day	Working capacity	Age, years	BMI	Days in CRP
Total	192	6,530±2,504	1.5±0.46	59±11	28.49±4.85	24±5
Male	160	6,584±2,534	1.56±0.45	59±11	28.49±4.54	24±5
Female	32	6,257±2,365	1.23±0.37	58±10	28.5±6.24	26±4
NYHA1	139	6,817±2,598	1.62±0.43	58±10	27.89±4.51	24±5
NYHA2	43	5,977±2,115	1.23±0.35	60±13	29.09±5.01	25±4
NYHA3	10	4,917±1,741	0.97±0.3	57±11	34.3±4.86	28±5
EF1	149	6,699±2,438	1.52±0.43	58±11	28.62±4.92	24±5
EF2	28	6,374±2,994	1.56±0.54	62±10	27.5±3.84	24±4
EF3	12	5,015±1,910	1.17±0.47	62±13	29.42±6.2	27±5
EF4	3	5,638±667	1.21±0.42	62±12	27.67±4.04	23±4
No coronary artery disease	18	6,613±2,034	1.48±0.41	51±14	28.94±5.12	26±4
Coronary artery disease 1	67	6,914±2,587	1.58±0.46	58±11	28.12±5.62	24±4
Coronary artery disease 2	65	6,649±2,702	1.54±0.42	60±10	28.71±4.38	24±5
Coronary artery disease 3	42	5,697±2,085	1.32±0.5	62±10	28.57±4.16	25±5
Normal weight: BMI 18.5–24	33	7,427±2,730	1.74±0.45	56±13		23±4
Overweight: BMI 25–29	98	6,448±2,393	1.59±0.43	62±10		24±5
Moderate obesity: BMI 30–34	36	6,751±2,393	1.34±0.36	55±10		25±5
Severe obesity: BMI 35–39	20	5,163±2,574	1.05±0.31	58±8		26±5
Very severe obesity: BMI >40	5	6,077±1,567	1.05±0.14	45±8		27±4

Abbreviations: BMI, body mass index; EF, ejection fraction; NYHA, New York Heart Association.

Figure 1 Optimal penalty parameter λ has been determined via 10-fold cross-validation.

Figure 2 Coefficient paths vs the penalty parameter λ (dashed vertical line: optimal penalty parameter l).

Table 2 Estimated coefficients of the linear regression effects on steps/day obtained by an additive model with a nonlinear effect for BMI

Parametric coefficients	Estimate	Standard error	t value	P(>[t])
Intercept	5,800.69	1,512.51	3.835	0.000173***
Age, years	–49.94	15.81	–3.185	0.001863**
Smoker	–986.17	484.13	–2.037	0.043113*
Ex-smoker	–1,125.36	344.97	–3.262	0.001322**
HDL	15.47	12.09	1.280	0.202176
Wmax/kg bodyweight	2,623.7	397.43	6.602	4.41e–10***
Beta-blocker medication	–277.7	316.82	–0.877	0.381913

Note:

* P-value<0.05,

** P-value<0.01, and

*** P-value<0.001.

Abbreviations: BMI, body mass index; HDL, high-density lipoprotein; W, watt.

Figure 3 Nonlinear effect of BMI on step outcome.

Abbreviation: BMI, body mass index.