Table 3.
Heart-rate variability, as compared to controls.
| References | HRV duration | Group | SDNN/RR | RMSSD | NN50/pNN50 | TP | LF | HF | LF/HF | α | Outcome | Quality (score between 0 and 22) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Bar et al. (2006) | 5 min | AN | ↑ | NS | Increased pain thresholds are associated with increased parasympathetic tone in AN but not AN-WR | 12 | ||||||
| 5 min | AN-WR | NS | NS | |||||||||
| Billeci et al. (2015) | 15 min | AN | ↑ | ↑ | ↓ | ↑ | ↓ | Prevalence of parasympathetic over sympathetic activity in AN | 14 | |||
| Billeci et al. (2019) | 5 min | AN | ↑ | ↑ | ↓ | ↑ | ↓ | Patients with AN demonstrated an altered autonomic response to light exercise (indicated SNS activation and PNS withdrawal) | 19 | |||
| Bomba et al. (2014) | 24-h | AN | ↑ | ↑ | NS | NS | ↑ | ↓ | Patients with AN demonstrated increased PNS at rest, which were mirrored (to a lesser magnitude) by patients with functional hypothalamic amenorrhea | 19 | ||
| Casu et al. (2002) | 5 min each: supine and orthostatic | AN | Supine NS; Orthostatic ↓ | NR | NR | NR | Patients with AN demonstrated abnormally persistent parasympathetic HRV modulation during an orthostatic challenge | 7 | ||||
| Galetta et al. (2003) | 24-h | AN | ↑ | ↑ | ↑ | NS | ↑ | ↓ | Patients with AN have a preserved sympathetic and increased parasympathetic HRV response to an orthostatic challenge, which may be compensatory mechanisms to starvation | 14 | ||
| Green et al. (2020) | 5 min | AN | NS | NS | There was no difference in cardiac autonomic balance between individuals with AN and HCs | 13 | ||||||
| Ishizawa et al. (2008) | 10 min | AN | ↑ | NS | ↑ | ↓ | ↓ | HRV in patients with AN demonstrated decreased SNS, increased PNS and increased complexity of inter-beat intervals, which may be a protective cardiovascular mechanism | 19 | |||
| Kollai et al. (1994) | 5 min | AN | ↑ | Patients with AN demonstrated high resting vagal activity | 8 | |||||||
| Koschke et al. (2010) | 30 min | AN | ↑ | ↓ | AN patients demonstrated resting vagal predominance which remained after controlling for BMI | 19 | ||||||
| Kreipe et al. (1994) | Supine: 256 s: Orthostatic: 15 min | AN (T1) | Supine ↓; Orthostatic NS | NS | Supine ↓; Orthostatic NS | AN patients demonstrated persistent PNS modulation in response to an orthostatic challenge and decreased resting SNS activity. This trended toward control values after 2 weeks of inpatient treatment | 10 | |||||
| AN-WR (T2) | NS | NS | NS | |||||||||
| Lachish et al. (2009) | NR | AN (T1) | ↓ | ↓ | ↓ | ↑ | ↓ | Individuals with AN demonstrated cardiovascular vagal hyperactivity, which persisted after short- and long-term weight restoration | 17 | |||
| NR | AN-WR (T2) | ↓ | ↓ | ↓ | ↑ | ↓ | ||||||
| NR | AN-WR (T3) | ↓ | ↓ | ↓ | ↑ | ↓ | ||||||
| Lonigro et al. (2019) | 5 min | AN | NS | Patients with AN demonstrated delayed recovery and stronger PNS activity in response to emotional attachment test, which may reflect altered emotion regulation | 13 | |||||||
| Lutz et al. (2019) | 5 min | AN | NS | Patients with AN demonstrated no significant difference in sympathetic cardiac modulation to HCs | 15 | |||||||
| Mazurak et al. (2011b) | 3 min each: supine, orthostatic, recovery | AN | Supine, recovery NS; Orthostatic ↑ | Patients with AN longer inter-beat intervals and weaker vagal withdrawal during an orthostatic test (independent from BMI) | 18 | |||||||
| Melanson et al. (2004) | 5 min; 24 h | AN | Short-term NS; 24-h, daytime: ↓ | Short-term NS; 24-h, daytime, night-time: ↓ | Short-term NS; 24-h, daytime, night-time: ↓ | Short-term NS; 24-h, daytime, night-time: ↓ | NS | Patients in various stages of recovery and refeeding demonstrated decreased resting and ambulatory measures of HRV with decreased parasympathetic activity | 12 | |||
| Murialdo et al. (2007) | 5.5 min each: supine, orthostatic | AN | Supine NS; Orthostatic ↓ | NS | Patients with AN demonstrated reduced SNS response to an orthostatic challenge. Disease duration and BMI were not correlated with HRV parameters | 10 | ||||||
| Nakai et al. (2015) | 5 min | AN | NS | NS | NS | Illness duration was negatively correlated with increased parasympathetic tone (HF) and positively correlated with lower vagal tone/high sympathetic tone (LF/HF ratio). This may indicate an initial adaptive response in AN with increased cardiac risk over a longer illness duration | 21 | |||||
| Petretta et al. (1997) | 24 h | AN | 24-h, daytime, night-time ↑ | 24-h, daytime, night-time ↑ | 24-h, daytime, night-time ↑ | 24-h, daytime ↑; night-time NS | 24-h, night-time ↑; daytime NS | 24-h, daytime, night-time ↑ | Patients demonstrated longer inter-beat intervals and increased parasympathetic activity over 24-h compared to thin and normal weight controls | 19 | ||
| Platisa et al. (2006) | 24 h | AN-C | NS | ↓ | ↓ | NS | Difference in HRV measures for acute and chronic AN; increased HRV in acute AN and decreased HRV in chronic AN. This may indicate the compensatory increased PNS tone in acute AN is attenuated over illness duration | 16 | ||||
| AN-A | NS | ↑ | ↑ | ↓ | ||||||||
| Rechlin et al. (1998) | 5 min each: supine and orthostatic | AN | ↓ | ↓ | Patients with AN demonstrated decreased sympathetic activity at rest and in response to an orthostatic challenge which trended to be reversed with weight restoration. Resting and orthostatic SNS activity were positively correlated with body weight. | 15 | ||||||
| AN-PWR | ↓ | NS | ||||||||||
| AN-WR | ↓ | NS | ||||||||||
| Roche et al. (2004) | 24 h | AN | ↑ | ↑ | NS | NS | ↓ | ↑ | 24-h HRV assessment demonstrated enhanced parasympathetic activity and withdrawal of sympathetic control | 13 | ||
| Rommel et al. (2015) | 2 min | AN | ↓ | In response to an emotional induction test, patients with AN displayed increased time required for parasympathetic activity to return to baseline, which may be a physiological disturbance due to emotion regulation deficits | 14 | |||||||
| Russell et al. (2008) | 20 min | AN | NS | NS | ↓ | NS | NS | NS | NS | Patients with AN demonstrated decreased pNN50 compared to HCs but did not differ in any other HRV parameters. HRV parameters in AN group differed from individuals with other EDs | 9 | |
| Tonhajzerova et al. (2020) | 5 min | AN | NS | There were no significant differences in cardiac-linked vagal modulation indexed by HRV HF in patients with anorexia nervosa, compared to controls | 21 | |||||||
| Vigo et al. (2008) | 10 min | AN | NS | NS | ↓ | NS | ↓ | Patients with AN demonstrated decreased HRV fractal scaling exponent and LF than controls. This pattern is similar to patients after myocardial infarction and may represent increased randomness of HR. | 17 | |||
| Wu et al. (2004) | 5 min | AN | NS | ↑ | ↑ | ↓ | Patients with AN demonstrated decreased SNS and enhanced PNS HRV activity. SNS (LF) was negatively correlated with anxiety and illness duration whereas PNS (HF) was positively associated with anxiety and illness duration | 13 |
AN, anorexia nervosa; AN-A, acute anorexia nervosa; AN-C, chronic anorexia nervosa; AN-PWR, previous diagnosis of anorexia nervosa, partially weight-restored; AN-WR, previous diagnosis of anorexia nervosa, weight-restored; BMI, body mass index; ED, eating disorder; HC, healthy controls; HF, High frequency power; HRV, heartrate variability; LF/HF, Low/high frequency power; LF, Low frequency power; NN50, Normal-to-normal intervals >50 ms (% of); NR, not reported; NS, not significant; PNS, parasympathetic nervous system; RMSSD, Root Mean Square of Successive Differences; SDNN, Standard deviation of normal-to-normal intervals; SNS, sympathetic nervous system; TP, Total power; T1, time 1; T2, time 3; T3, time 3; α, Short-term fractal scaling exponent.