Limits...
Baroreflex sensitivity and its response to deep breathing predict increase in blood pressure in type 1 diabetes in a 5-year follow-up.

Rosengård-Bärlund M, Bernardi L, Sandelin A, Forsblom C, Groop PH, FinnDiane Study Gro - Diabetes Care (2011)

Bottom Line: Spontaneous BRS declined over time (BRS(average) 16.2 ± 0.8 vs. 13.2 ± 0.8 ms/mmHg; P < 0.01), but the change was not significant when adjusted for time of follow-up.Low BRS at baseline did not progress to cardiac autonomic neuropathy but predicted an increase in the nighttime systolic blood pressure (BRS(average) r = -0.37; P < 0.05).Early interventions aiming to reduce sympathetic overactivity in patients with low BRS might delay the development of hypertension.

View Article: PubMed Central - PubMed

Affiliation: Division of Nephrology, Department of Medicine, Helsinki University Central Hospital, Helsinki, Finland. per-henrik.groop@helsinki.fi

ABSTRACT

Objective: We have recently demonstrated that early autonomic dysfunction, defined as low baroreflex sensitivity (BRS), could be functional and reversible. However, potential temporal changes in BRS have not yet been addressed by longitudinal studies in type 1 diabetes. Moreover, it is not known whether low BRS predisposes to hypertension or other nonfatal diabetes complications.

Research design and methods: We conducted a 5-year prospective study including 80 patients with type 1 diabetes. We measured ambulatory blood pressure and autonomic function tests. BRS was assessed by six different methods during spontaneous, controlled, and slow deep breathing at baseline and follow-up.

Results: Spontaneous BRS declined over time (BRS(average) 16.2 ± 0.8 vs. 13.2 ± 0.8 ms/mmHg; P < 0.01), but the change was not significant when adjusted for time of follow-up. Low BRS at baseline did not progress to cardiac autonomic neuropathy but predicted an increase in the nighttime systolic blood pressure (BRS(average) r = -0.37; P < 0.05). Additionally, BRS response to deep breathing at baseline predicted an increase in 24-h ambulatory blood pressure (BRS-αLF r = 0.323-0.346; P < 0.05).

Conclusions: The decline in spontaneous BRS over time in patients with type 1 diabetes seems to be due to normal aging, which supports a functional etiology behind early autonomic derangements. Decreased resting BRS and the magnitude of improvement by deep breathing may be due to sympathovagal imbalance, a well-known mechanism in the development of hypertension. Early interventions aiming to reduce sympathetic overactivity in patients with low BRS might delay the development of hypertension.

Show MeSH

Related in: MedlinePlus

Correlations between baseline spontaneous BRS and change in nighttime SBP during 5-year follow-up.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3198281&req=5

Figure 1: Correlations between baseline spontaneous BRS and change in nighttime SBP during 5-year follow-up.

Mentions: The correlations between baseline spontaneous BRS-variables and change in nighttime SBP are shown in Fig. 1. Only patients without AHT are included (n = 50). The lower BRS at baseline, the more the nighttime SBP increased over time (r = −0.348 to −0.381; P < 0.05). In addition to resting BRS, we also calculated the increase in BRS induced by deep breathing at baseline (data not shown). Two of the BRS methods showed a significant correlation with the increase in blood pressure over time, mainly with 24 h (BRS-αLF r = 0.323–0.346, P < 0.05; BRS-SD r = 0.352–0.454, P < 0.05) and nighttime (BRS-αLF r = 0.303–0.434, P < 0.05; BRS-SD r = 0.333–0.481, P < 0.05) indices and with daytime MAP (BRS-αLF r = 0.302, P < 0.05; BRS-SD r = 0.339, P < 0.05). With the other BRS methods the correlations between the response in BRS and blood pressure variables were nonsignificant.


Baroreflex sensitivity and its response to deep breathing predict increase in blood pressure in type 1 diabetes in a 5-year follow-up.

Rosengård-Bärlund M, Bernardi L, Sandelin A, Forsblom C, Groop PH, FinnDiane Study Gro - Diabetes Care (2011)

Correlations between baseline spontaneous BRS and change in nighttime SBP during 5-year follow-up.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3198281&req=5

Figure 1: Correlations between baseline spontaneous BRS and change in nighttime SBP during 5-year follow-up.
Mentions: The correlations between baseline spontaneous BRS-variables and change in nighttime SBP are shown in Fig. 1. Only patients without AHT are included (n = 50). The lower BRS at baseline, the more the nighttime SBP increased over time (r = −0.348 to −0.381; P < 0.05). In addition to resting BRS, we also calculated the increase in BRS induced by deep breathing at baseline (data not shown). Two of the BRS methods showed a significant correlation with the increase in blood pressure over time, mainly with 24 h (BRS-αLF r = 0.323–0.346, P < 0.05; BRS-SD r = 0.352–0.454, P < 0.05) and nighttime (BRS-αLF r = 0.303–0.434, P < 0.05; BRS-SD r = 0.333–0.481, P < 0.05) indices and with daytime MAP (BRS-αLF r = 0.302, P < 0.05; BRS-SD r = 0.339, P < 0.05). With the other BRS methods the correlations between the response in BRS and blood pressure variables were nonsignificant.

Bottom Line: Spontaneous BRS declined over time (BRS(average) 16.2 ± 0.8 vs. 13.2 ± 0.8 ms/mmHg; P < 0.01), but the change was not significant when adjusted for time of follow-up.Low BRS at baseline did not progress to cardiac autonomic neuropathy but predicted an increase in the nighttime systolic blood pressure (BRS(average) r = -0.37; P < 0.05).Early interventions aiming to reduce sympathetic overactivity in patients with low BRS might delay the development of hypertension.

View Article: PubMed Central - PubMed

Affiliation: Division of Nephrology, Department of Medicine, Helsinki University Central Hospital, Helsinki, Finland. per-henrik.groop@helsinki.fi

ABSTRACT

Objective: We have recently demonstrated that early autonomic dysfunction, defined as low baroreflex sensitivity (BRS), could be functional and reversible. However, potential temporal changes in BRS have not yet been addressed by longitudinal studies in type 1 diabetes. Moreover, it is not known whether low BRS predisposes to hypertension or other nonfatal diabetes complications.

Research design and methods: We conducted a 5-year prospective study including 80 patients with type 1 diabetes. We measured ambulatory blood pressure and autonomic function tests. BRS was assessed by six different methods during spontaneous, controlled, and slow deep breathing at baseline and follow-up.

Results: Spontaneous BRS declined over time (BRS(average) 16.2 ± 0.8 vs. 13.2 ± 0.8 ms/mmHg; P < 0.01), but the change was not significant when adjusted for time of follow-up. Low BRS at baseline did not progress to cardiac autonomic neuropathy but predicted an increase in the nighttime systolic blood pressure (BRS(average) r = -0.37; P < 0.05). Additionally, BRS response to deep breathing at baseline predicted an increase in 24-h ambulatory blood pressure (BRS-αLF r = 0.323-0.346; P < 0.05).

Conclusions: The decline in spontaneous BRS over time in patients with type 1 diabetes seems to be due to normal aging, which supports a functional etiology behind early autonomic derangements. Decreased resting BRS and the magnitude of improvement by deep breathing may be due to sympathovagal imbalance, a well-known mechanism in the development of hypertension. Early interventions aiming to reduce sympathetic overactivity in patients with low BRS might delay the development of hypertension.

Show MeSH
Related in: MedlinePlus