Table 4. Association of heart rate with non-fatal respiratory complications (pneumonia or exacerbation) in 402¹ patients with a diagnosis of chronic obstructive pulmonary disease.

Heart rate	Person-years	Pneumonia or exacerbation	Incidence/1000 person-years (95% CI)	Crude HR (95%CI)	P value	Adjusted HR2 (95%CI)	P value	Adjusted HR3 (95%CI)	P value
Continuous	1234	179	145 (120–168)	1.14 (1.03–1.26)	0.010	1.13 (1.03–1.25)	0.013	1.07 (0.96–1.18)	0.208
≤80 bpm	975	128	131 (110–156)	Reference		Reference		Reference
>80 bpm	259	51	197 (148–257)	1.5 (1.1–2.0)	0.18	1.5 (1.1–2.0)	0.021	1.1 (0.8–1.6)	0.437

Heart rate was categorised in steps of 10 bpm, when analysed as a continuous variable. In total 310 patients had a heart rate ≤80 bpm and 95 patients had a heart rate >80 bpm.

COPD: chronic obstructive pulmonary disease, HR: hazard ratio, CI: confidence interval, bpm: beats per minute.

¹Two patients were excluded as they were censored before the earliest event occurred. In one patient we had no follow-up data.

²Adjusted for sex, and age.

³Adjusted for sex, age, pack-years of smoking, FEV1 (% predicted), use of cardiovascular drugs (β-blockers excluded), and β-blockers.