Accuracy of Apple Watch to Measure Cardiovascular Indices in Patients with Chronic Diseases: A Cross Sectional Study

Figures & data

Figure 1 Patient flowchart.

Table 1 Pearson or Spearman Correlation Between Apple Watch and Pulse Oximeter (Contec) in Patients with Chronic Diseases for Oxygen Saturation at Rest and After Exercise

	Mean (SD) of Practical (Apple Watch)	Mean (SD) of Criterion (Contec)	R (p value)
SpO2 at rest for hypertension patients	96.99(1.04)	96.71(1.06)	0.88(<0.001)
SpO2 at rest for diabetic patients	96.49(0.95)	96.27(0.76)	0.95(<0.001)
SpO2 at rest for dyslipidemia patients	96.88(1.42)	96.62(1.22)	0.001(<0.001)
SpO2 at rest for all chronic patients	96.83(1.11)	96.57(1.00)	0.92(<0.001)
SpO2 after exercise for hypertension patients	96.86(1.36)	96.66(1.05)	0.84(<0.001)
SpO2 after exercise for diabetic patients	97.02(0.76)	96.89(0.65)	0.81(<0.001)
SpO2 after exercise for dyslipidemia patients	97.00(1.48)	96.76(1.27)	0.97(<0.001)
SpO2 after exercise for all chronic patients	96.94(1.23)	96.74(1.00)	0.87(<0.001)

Abbreviations: R, Pearson or Spearman correlation coefficient; SD, Standard deviation; SpO2, Oxygen saturation.

Figure 2 Blood oxygen correlation at rest for all patients with chronic diseases.

Figure 3 Blood oxygen correlation after exercise for all patients with chronic diseases.

Figure 4 Blood oxygen at rest for all patients with chronic diseases.

Figure 5 Blood oxygen after exercise for all patients with chronic diseases.

Table 2 Pearson or Spearman Correlation Between Apple Watch and Polar Chest Strap in Patients with Chronic Diseases for HR During Whole Session

Outcomes	Mean (SD) of Practical (Apple Watch)	Mean (SD) of Criterion (Polar)	R (p value)
HR for Hypertension patients	102.33(11.68)	102.35(11.63)	0.001(<0.001)
HR for diabetic patients	103.58(10.10)	103.62(10.08)	0.001(<0.001)
HR for dyslipidemia patients	104.88(7.23)	104.84(7.10)	0.001(<0.001)
HR for all chronic patients	103.29(10.15)	103.30(10.10)	0.99(<0.001)

Abbreviations: R, Pearson or Spearman correlation coefficient; HR, Heart rate; SD, Standard deviation.

Figure 6 Heart rate for all patients with chronic diseases.

Figure 7 Heart rate correlation for all patients with chronic diseases.